text
stringlengths 22
2.11M
|
|---|
[Question]
[
So, in my story, the entire world has just gone to absolute crap. The largest war in human history, WW3 in October 1962, has just caused destruction in most of the United States, the Soviet Union, Europe, and populated sections of China.
About half a millennium later, in the year 2468, America is a twisted land, especially the Great Plains of North America. In a 100 miles stretch of land, from North Dakota to Iowa, there is a horrific threat: the Buffalo Men.
The Buffalo Men are a tribe of cow herders who ride on horseback across the Plains. They are pagans, who believe Mother Earth and Father Sky punished mankind for their arrogance and misuse of technology. They often go on raids, burn down cities, kill and enslave people, and other nasty things. They are important to my plot.
But I can’t wrap my head around one fact. The Buffalo Men live in the Great Plains, where farming land is abundant and useful. It would make more sense for them to settle down and farm to get more resources. So, my question is: what is a logical explanation for why the Buffalo Men don’t start farming?
[Answer]
**Sedentary Lifestyles aren't Necessarily Easier**
The problem with being a sedentary farmer is that once you get your seeds in the ground you now have a long standing commitment to care for that plot of land. Folks don't really know nowadays because all our food comes from the grocery store, but pre-industrial farming ain't easy. Its 12 hour work days 7 days a week for months on end, followed by a frenzy of panicked activity. This burst of frenetic labor will hopefully result in a harvest, weather, pests, crop choice, soil chemistry, and water availability permitting. If just one of those variables goes wrong guess what? You better be ready to heavily reduce or quit that whole eating habit until next year. Contrary to popular belief, people did not always experience famines in the dead of winter unless that year was REALLY bad. They starved in the summer because that's the period farthest from the last harvest. Imagine the maddening feeling of starving to death while luxurious green lush plants that aren't bearing fruit yet are growing from the soil. Pre-industrial farming was not fun. It was a ton of work, sometimes for little to no return on investment.
The other problem in a situation where social cohesion has broken down is that you are stuck defending that plot of land. Those lush green crops coming in perfectly (thanks in no small part to your and your entire clan or tribe's slavish back breaking labor) are a huge billboard that says "You could probably pillage the crap out of us." So on top of the grueling labor you also need to figure out how to defend a vary large plot of land. In summary, the reasons why farming sucks are back breaking labor, predatory neighbors, and no guarantee that you will even get fed once it's all done. Last but not least, if things don't go your way you are stuck there suffering through it. You cannot just pack up an entire farm and move it to someplace where conditions are better and attackers are farther away, right?
Or could you....?
**Yes You Can**
Nomadic Herdsmen are in the simplest terms, mobile farmers. They are simply raising animals instead of crops. If the rain is bad and there isn't enough water for the herd, pack it up and move it. Not enough grasslands to graze? Pack it up and move it. Hostile neighbors you don't think you can fight and win against? Pack it all up and move it. Your options for handling crisis are a lot wider than that of a sedentary farmer. The attributes of this lifestyle have throughout history been attractive enough for entire cultures to form around nomadic herding, many of which have been quite successful and prosperous. When there is enough unoccupied land and there are suitable domesticated species to herd you will always find herdsmen moving from place to place with their animals.
**Nomadic Herdsmen Have Historically Been Violent**
There is a major downside to being nomadic, and its that you can't really specialize in anything. Those finer things in life that require complex manufacture are not going to be made by nomadic people. See, sedentary farming has its drawbacks, but once it has gotten up and running it tends to produce enough surplus for people to not *always* have to be farming. These people use this free time to specialize in stuff like making complex goods, selling rare and exotic goods, soldiery and weapons making and then trade their services or wealth with the farmers for food (or declare yourself leader and tax everybody for it). To be sure, tribesmen are usually perfectly willing to trade for things they can't make. But the other problem is that when sedentary agricultural societies begin to do well they tend to explode in population requiring more land, more water, and more space.
After a while the combination of shrinking pastures, lack of complex resources and wealth, and a general tough and mobile unattached lifestyle makes raiding the dirt farmers for things you want more and more attractive. They are rich, you are poor, they are fat, you are scrappy, and just look at em, sitting there with all that *cool stuff* so much more than they could ever possible carry. Just growing food on all that land they have and not even raising one cow! They're basically *begging* to be raided!
After a while nomadic herdsmen figure out that following a bunch of dumb animals everywhere isn't as cool as it used to be compared to how profitable jacking a bunch of farmer's stuff is. They still do the nomadic herd thing, they can't be raiding *all* the time. But come raiding season (usually late summer and early fall) its time to go get some cool new goodies, free coin, and maybe try out some different women who don't smell like horses and cow paddies. Believe it or not entire nations were (pardon the very distateful pun) sacked by nomadic raiders because they had exceptionally pretty women. It is an unfortunate fact of history that rape was a very major motivating force for raids.
[Answer]
The greatest problem European settlers had with the Great Plains was the land itself. The endemic grasses were so deep and thick that they would break iron plows. There are [other important reasons](http://www.bbc.co.uk/schools/gcsebitesize/history/shp/americanwest/farmersproblemsrev1.shtml) which prohibited farming; little rainfall, no wood for construction/fences, abundant insects (grasshoppers, Colorado beetle), and lawlessness.
These problems were overcome with technology provided by the coming of the industrial revolution. Steel plows were a major breakthrough, and John Deere's [self-scouring steel plow](https://en.wikipedia.org/wiki/John_Deere#19th_century) (1846) was a game changer. It was so successful his legacy evolved into a multinational corporation famous for big green tractors.
Other innovations, such as barbed wire (1874), allowed the construction of fences to help keep pesky animals off your farm. The railroads (1866) allowed subsistence farmers to become commercial farmers, as they could export to consumer markets that would have been too far away.
Perhaps the biggest innovation, however, was [the windmill](https://nature.berkeley.edu/departments/espm/env-hist/studyguide/chap9.htm) (1880). This allowed the pumping and storage of water, which was essential given the lack of rainfall.
It almost goes without saying that modern pesticides were crucial in curbing the damage caused by various crop-munching insect species.
These inventions all occurred from the mid 1800s, requiring industrial technology and infrastructure. Without that farming will be too difficult. Especially given a lawless society.
[Answer]
The American Great Plains may contain abundant and useful farming land *now*, but that doesn't mean that it always has, or that it'll stay that way. A strong part of why that land is useful is because it has regular rainfall. VERY regular rainfall by comparison to many other regions of the globe. The consistency of weather is its real value, but you have to remember is that weather patterns change.
The Sahara is currently one of the most barren deserts on the planet, but seems to go through a regular 30k year or so cycle of greening, then back to desert.
Several South American civilisations crumbled almost overnight due to drought in previous millennia, and the need for the inhabitants to migrate to find water.
On geological timescales, even Antarctica was a verdant rainforest.
Sure, we're only talking about 500 years but you have to remember that we've just converted these plains to wasteland through nuclear weapons at the beginning of that time. There just isn't enough science (thank goodness) on what would happen to the plains as a result of the nuclear winter, or if other changes to the environment as a result of the war would have cumulative effects on that land over a 500 year period.
Finally, if the farmland is useful for crops, it's also useful for pasturing, meaning that being herders may also be a lifestyle choice. Admittedly, this is less likely from an efficiency perspective; it takes a lot more energy (and water) to herd meat than it does to grow crops, but there could also be a safety factor involved, especially from early on after the war; a static patch of land with your crops on it has to be defended at all costs from raiders and the like, but with a herd you at least have the option to run instead if the odds are not in your favour.
Between ecological change, no access to modern farming technology, and emergent culture, there's probably some plausible reasons for them to do this but ultimately the impact of a nuclear war on farmland is likely to be devastating for at least a generation or two who try to subsist off the land. This would be especially so given the sudden disappearance of modern fertlisers, insecticides, GM seeds, etc.
That might be enough to get people out of the habit.
[Answer]
I understand that you are trying to round out some civilization that you've been thinking about in your head and in this effort I have always found that going to past civilizations for inspiration has fruitful results. I think that you're fairly lucky in that you're working with an alternate history set int America and we can actually take a look at some of the Civilizations that lived in the exact parts of the world that you're interested in and ask the same question - Why were the Great Plains Indians migratory peoples, even after farming was introduced to them?
1. **Farming (successfully) is hard.**
Today we have the benefit of seeing these superfarms - of acres and acres of green - and might see this as hard to believe. But before we had motorized farm tools, we had domesticated animals. Before those, we had iron tools. Before those, we had stone tools. Take a look at New America when the Spanish were settling Texas - there were Spanish Friars who knew exactly how to successfully build an irrigation system for their farmlands and it still required them digging a 15 mile Aqueduct (Espada Aqueduct in the 18th century) almost purely by hand to redirect the water necessary to sustain themselves. This also required dams, water locks, and actual Aqueduct officials to go in on a daily basis and say whether or not the aqueduct locks should be lowered or raised based on the day's needs and the water levels. To be short about it, even the simple matter of getting water to crops can be incredibly difficult.
2. **Comanche followed the buffalo.**
This is ultimately a reductionist argument on what is an extremely complicated and difficult topic of Plains Indian cultural and societal structure, but even massive reductionist pictures can be sparks of inspiration for worldbuilding. The typical Comanche was born into a society that hunted Buffalo. They did not know any different, and they knew that this was a successful way of life. Males would go out and hunt and women (who definitely had the short end of the stick on this whole deal) would clean, tan, cut, stretch the hide (in addition to raising the children, cooking, and maintaining the household). The buffalo, as we know from history, was an incredible resource to people. The numbers of buffalo at the time were also exorbitant - I have no doubt that the average Plains Indian would look in awe upon the hordes of them that covered the earth and could never guess that any one peoples could hunt them to extinction (spoiler - we did).
3. **At the end of the day, peoples tend to propagate what their mothers and fathers did**
Which is just my way of saying, there's a lot of "we don't know why" when it comes to "why did people do this?" We know that they didn't have spreadsheets at the end of the day with a theoretical food yield of farming they could compare to the total food gained through hunting per year. People have a compulsive desire to eat and to have some level of trust in their methodology for fulfilling that desire. They're resistant to change. We may not be able to say "we know why the Plains Indians weren't originally farms" but we can say "we know why generation after generation continued what their fathers did - because it worked".
I would take that into account when making civilizations as part of world building. If you try and map out the why and what of every single instance of peoples, you'll go insane. It's just not a feasible goal. Take a vision you have in mind for a people and go with it. They'll evolve as you think and write more into them, and eventually that evolution will lead to more questions than you began with. You'll never have all the answers - which is my favorite part. It's what makes your creations interesting - give your readers the questions and let them ponder on all the possible solutions.
[Answer]
Poor soil quality.
This means its hard to grow crops and the crops have low and inconsistent yields. To account for a larger population, they need to farm much more land than practical due to the lower yields. So you have huge swaths of grasslands and tons of room for potential farms, however there just isn't enough nutrients in the soil to make it effective enough to settle down in one location.
Grass itself is a very tough plant and one of the most abundant. It will try to grow anywhere. Rather than farm grains, you farm animals that live off the grass. This means you don't need to tend to the grass, you just tend the herd. The herd will move along and find fresh batches of grass as it eats its way across the farm lands. You basically get to cover a much larger area and aren't subject to localized events which may cause a crop to potentially fail and waste an entire seasons harvest.
[Answer]
Twentieth century farming relied on industry to achieve its fantastic yields. Hybrid seeds, combine harvesters, tractors, and irrigation pumps are not tools that a society that has reverted to barbarism will be able to re-generate easily. In our world, they took centuries to develop. The profits from vast markets were used to build the factories that made them.
Without the aid of these technologies, crop yields are much lower. (Like 90% to 97% lower.) As shown repeatedly in the [*Little House on the Prairie* series](https://rads.stackoverflow.com/amzn/click/0545422736), the Great Plains are prone to natural disasters that make it hard to make a living as a subsistence farmer. The winters are harsh; the summers are hot; sometimes there are droughts; and plagues of locusts cannot be ruled out.
Furthermore, even if a majority of the Buffalo Men decided to settle down and farm, they would likely be wiped out be the remainder. Without the backing of a great power's army, isolated settlers would be at great risk from the violent nomads.
[Answer]
>
> the Great Plains, where farming land is abundant and useful
>
>
>
False!
The Great Plains are actually pretty terrible for agriculture. We can use them today by pumping the Ogallala aquifer dry at an unsustainable rate, and through a stable society where a few years of drought mean an insurance claim, not starvation and death.
Great plains Indians largely survived on a nomadic lifestyle, following buffalo herds for sustenance. Agriculture was the exception, largely limited by the availability of water. Security and peace is also a necessary input, if one intends to be around for the harvest.
In modern times, we obtain water from rivers and underground aquifers. Aquifers can be pumped dry, as is happening to the [Ogallala aquifer](https://www.scientificamerican.com/article/the-ogallala-aquifer/) today. [Rivers aren't immune to depletion either](http://pacinst.org/publication/water-to-supply-the-land-irrigated-agriculture-in-the-colorado-river-basin/). Aquifers can take [hundreds or thousands of years to replenish](https://www.nytimes.com/2013/05/20/us/high-plains-aquifer-dwindles-hurting-farmers.html?smid=pl-share).
So a return to a nomadic, buffalo-based way of life in that area is really not difficult to imagine, based on both historical context and modern scientific fact. Coupled with a societal collapse which means a loss of the infrastructure to drill wells and produce/maintain center-pivot irrigation systems, and a mature and stable economy that can sustain farmers through years of drought you should have little difficulty explaining your Buffalo Men, while covertly educating your readers about a real fact of modern life!
[Answer]
Other answers have considered soil quality. The major missing element for agriculture though is
### No good quality human-edible plants which can keep you fed all year.
In order to make farming work, you need plants which you can eat, and they need to keep you going all year. Any gaps, you need to be able to store your produce to tide you over.
European and Asian agriculture is largely based on grains of various types of grass. If no current varieties of grass have big enough seeds with enough energy density to make it worthwhile collecting them for food, or if the grass itself cannot be eaten or stored effectively, then that won't work.
Other agriculture relies on plants with edible roots. This is perhaps more reliable, because there are many suitable plants all round the world. However you need these roots to feed you all year. If they only have limited growing seasons because of the weather, or if they simply don't store well, then you're going to spend a lot of time hungry.
Animals simply don't have this problem. They feed themselves, and you can eat a few over the lean months.
When the good weather comes, of course you can pick fruit and vegetables in the area around you, taking advantage of a glut as it happens. You may even be able to store some of it. But that's luxury food. What really keeps you alive in winter is your animals.
[Answer]
In a dystopian future, we might not have the ability to make chemical fertilizers anymore (especially if [we've run out of phosphorus by then](https://en.wikipedia.org/wiki/Peak_phosphorus). Places that are fertile today might not stay that way after centuries of taking from the land with very little returning. It's not just a case of taking valuable nutrients from the soil, either, but destroying the crucial ecosystem of insects, fungi, and bacteria.
# Knowledge was lost before the land could be restored
In theory, it could take multiple generations to rejuvenate the land the way our ancestors used to do over 200 years ago: rotate which fields are used as pasture and which ones are for crops. The Buffalo Men could have been descendants of farmers who bet on being able to return to a 2-year rotation after a few years of herding exclusively in an attempt to return some of the lost organic content in the soil. This plan took longer than expected and few people remain that have the agricultural know-how to do it.
# Lack of seeds to plant
It might also be a case of not having any viable seeds anymore. Some seeds last longer than others, but if you lose the ability to preserve them (ie. refrigeration), there might not be enough seeds left for everyone who wants to take up the hoe by the time the land is restored.
# Reliance on livestock sabotaged the restoration efforts
[Documentary on the restoration of the Loess Plateau](https://www.youtube.com/watch?v=8QUSIJ80n50).
In 1995, experts across the world were called in to help restore the Loess Plateau in China (an area the size of France), which had been severely degraded after centuries of farming. They cited uncontrolled overgrazing as the biggest reason the land could never recover. Without the Chinese government to compel the people to follow the restoration plan, at best it could have taken much longer than the ~20 years this documentary covers to see an improvement. At worst, the land gets worse.
[Answer]
**Wildfires**
Fire can burn all your crop. It can also burn the grass that animals feed on, but there should always be grass, and hence animals, somewhere on the great plains.
[Answer]
Most of the answers here focus on ecology so I'll focus more on culture/politics instead
**Hostile Culture**
Your 'Neo-Tengriist' tribe are warlike by culture and adopted the appropriate lifestyle to suit them, or maybe it was the other way round. Being nomadic means they are unable to produce the more specialised goods that a sedentary lifestyle and the associated infrastructure would provide, but they do so on purpose. They make it a point to seize what they lack from their neighbours by force of arms. Nomadism also helps in mitigating the resulting military retaliation since they can pack up everything and run. Their ancestry would probably include a line of extremely skillful military leaders like [Subutai](https://en.wikipedia.org/wiki/Subutai), which would embolden their descendants to interact with their neighbours primarily through violence.
This sort of raiding lifestyle tends to result in taking a large number of slaves, which is actually a pretty big incentive for transitioning to a sedentary way of life. To mitigate this, you can simply have your tribe use their slaves in ways that produce an extremely high attrition rate, possibly ritual sacrifice. If not, you can simply have them self-regulate. Their leaders are aware of the burden of having many slaves and don't wish for the tribe to become shackled by this. They want their descendants to remain warriors who prey on their inferior neighbours at will, so they opt to execute most of their prisoners and only keep a 'skeleton crew' as slaves.
[Answer]
Say they tried farming early in their history, but a dust bowl-type event wiped out all their farms so they basically gave up on farming and became hunters instead, like the Native Americans in the centuries of old.
] |
[Question]
[
In [this](https://i.stack.imgur.com/YUKww.jpg) picture, we see a futuristic cityscape, with what seems to me an unexpected occurrence: a fairly normal-looking *barge* chugging along down the river! That just looks out of place, and it brought to mind my question.
In ~500+ years, will we, or I suppose any other civilization with similar planets and technology, require vehicles for human travel or goods transportation that are bound to rivers and such? They are mostly used now due to large cargo space available per ship, and cheapness compared to air, but I would have thought that in a situation depicted here, we would by then have advanced past the slow, location-constrained, water-based methods. But assuming I'm wrong, what would be the reasons for this tech still to exist in the far future, beyond the occasional tycoon's pleasure cruise?
[Answer]
We'd send things by ship for the same reason we do today. **It's cheap.** It's not likely that individuals, corporations, or governments of the future would not be motivated by the cost savings associated with transport by ship.
Unless there is some magical energy source in the future that makes energy free, or nearly free, in terms of monetary and environmental costs we will likely always use waterways where possible.
Without this energy source, it may be that, after peak oil, fuel will be so expensive that transporting cargo by aircraft will be prohibitively expensive. So people of the future will look at photos of cargo planes and think that *we* are the crazy ones.
[Answer]
Even if we do create a free energy source, heavy freight will still be transported by water because it is safer.
With free energy, we probably could transport massive items by air, but the risk to those living under their flight plans would be unreasonable. One faulty circuit which blows at the wrong moment, and thousands of tons of freight could be returning to earth violently.
[Answer]
Why would we **not** be using water transport in 500 years' time? Ships are an extremely efficient way of transporting large volumes of non-time-critical cargo. They also require relatively little infrastructure: if you're using the ocean or rivers, you really only need a place to park the ship and equipment to load and unload it at each end of the journey. (The same is true of planes but not trucks or railways.)
So maybe we won't care about energy efficiency very much when we finally invent that "free" energy source (e.g., fusion power). Well, that isn't necessarily the case. Perhaps the "free" power relies on economies of scale. Maybe we can sensibly build fusion power stations for cities but not for "small" things like ships and aircraft. That's basically what happened with (fission) nuclear power: only a handful of nuclear-powered cargo ships were built, even at the time when nuclear power was the sexiest thing going and we weren't very worried about radioactive waste and so on. Even with miniaturized free power, it might still be cheaper to put all your stuff in a ship with a big diesel engine and a few crew (or even totally automated) and wait a few weeks.
And if we're not using water for bulk transport, it seems we'd have to use the air. But air travel really isn't suited to bulk transport. One of the standard, large-ish sizes of ocean-going bulk ship carries about 50,000 tons of cargo. Suppose you had a "free" energy source and you put that cargo in a plane instead. First, it has to take off, by forcing enough air downwards that the force exceeds the weight of the craft and its cargo. Better not do that near any population, because the downdraft and noise are going to be extremely destructive. Now suppose we're airborne. 50,000 tons moving at 100 metres per second (about 225mph) at 30,000ft has about 2.5x10^11 joules of kinetic energy and 5x10^12 joules of potential energy. That total amount of energy is about one seventeenth of the energy released by the Hiroshima bomb. From time to time, these things will fall out of the sky. When that happens, they will make a big mess on the ground. And note that one of the reasons air travel is so safe is that there are a lot of airports around so, if something goes wrong, a plane can divert to the nearest suitable airfield (or [not-so-suitable airfield](https://en.wikipedia.org/wiki/Gimli_Glider) or even [not-an-airfield-at-all](https://en.wikipedia.org/wiki/US_Airways_Flight_1549) if the situation is urgent enough). Because of their need for specialist facilities, giant cargo planes would be much more limited in their ability to divert.
Finally, you may be underestimating how much freight travels by ship today. It's easy to imagine shipping as being something mostly from the past but it emphatically is not. Just think of the amount of "Made in China" stuff you see in the shops. All of that came by ship. All. Of. It. The plastic all that stuff is made from? That's made from oil that was mostly transported by ship. Or it's recycled from waste that was transported by ship. (Quite a large fraction of what those container ships take back to China is waste plastic for recycling, rather than just sending back empty containers.) You see those cars on the road? A good fraction of the steel in them was made from iron ore that was transported by ship. Huge amounts of grain are transported around the world – by ship, 50,000 tons at a time.
[Answer]
If we look at the imaginations of futurologists of yesteryear, and their expectations of what we'd have today, two things stand out, at least to me:
* They were wrong about the cool stuff that they expected would be commonly used by everyone. Meals in a pill, robot maids, flying cars, jetpacks, supersonic trains and planes, moving sidewalks, weather control, rotating space stations with artificial gravity, moon stations and so on.
* They were wrong when they were right. When Flash Gordon leaps out of the spacecraft he clips on his little levitation belt instead of a parachute, and grabs the briefcase-sized communicator radio. The videophone is not wireless, but rather built into the wall of a house, with a CRT and everything.
So, in general, it seems best, when looking at the past, to assume that things will NOT change, unless there's a clear sign that technology must inevitably change things. What technology could come along that will make shipping obsolete? Better roads?
But if the factories already exist by the rivers/dams for cooling, and for proximity to power generation, surely the rivers will remain the best way to get the materials to the factories, and to get the output away?
Any visit to any lake or beach in the US on the weekend will tell you that there will never, ever be a day, in any conceivable future, where pleasure craft will be obsolete. Instead, what we can guarantee is that the existing plethora of designs will be joined by newer ones as the tachnologies advance. But there'll still be people who like a sailing dingy, or a kayak, not because, nowadays, they are any more practical than an inflatable dingy with an outboard motor, or a jet-ski, but because they are more pleasurable. These places, as populations rise, just become more teeming with craft, not less.
Same with cruises, and yachts.
So if shipping, cruises, yachts, and small recreational craft still exist, what does that leave, to get rid of?
Passenger craft is one - in Bangkok, taxi-boats ply the canals, but they wouldn't be needed if the canals were paved over. But why would people do that? The canals bring business and shipping and look nice and provide drainage in floods. So, odds are the small canal-taxis will continue to exist, even if their drivers become automated.
Ferries are still used where there are no toll-free tunnels or bridges, and people want to take something heavy, like their car, to their destination.
What about larger passenger ships? Well, long distance, that service has by and large been replaced by planes already. People coming to the US from Europe now fly, rather than take a ship.
Overall, I can't see any technology which will further remove water craft.
[Edit:
>
> the reasons for this tech still to exist in the far future, beyond the occasional tycoon's pleasure cruise?
>
>
>
That line, I realized, was the one that felt most wrong to me. It doesn't work like that. Stuff gets cheaper. That swarm of pleasure craft is only going to get bigger as materials science and manufacture get more advanced and the craft become cheaper. Why would water ever become the domain only of "tycoons", rather than the birthright and pleasure dome of everyone who lives nearby?
Perhaps if laws are passed to protect the water from the people - but even then they'll sneak in.
Perhaps if the waters became dangerously polluted, then at least fishermen might no longer take to sea, and people wouldn't swim in it any more... but even then, people would cruise upon the waves, just not swim in them.
As it becomes more crowded on land, the space and freedom of the open sea will become more and more intoxicating, and more and more people will be pushed to live there, some permanently. It's a valid solution to overpopulation. Sure, the wealthy might have their own ships, but link together a long enough bunch of cheap rafts connected with dynamos, and the wave power can generate electricity for the community. Who needs to be rich?]
[Answer]
I'll open with a quote from Donald Knuth:
>
> Never underestimate the bandwidth of a station wagon full of tapes
> hurtling down the highway.
>
>
>
What he means is this: say you're carrying a box of 100 4TB hard drives. Say you're traveling at 60mph. Your data transfer rate is ~1500TB/1.6s. Consider that your best download speed MIGHT be on the order of 2-3MB/s then you'll understand why his joke... isn't a joke.
The biggest reason why (in terrestrial environments) you'll never see barges go away is that *even assuming* massive gains in energy efficiency, it still takes more energy per unit of mass to make a plane fly than it does to make a barge move in the water. Which then also means your fuel cost for a barge will be cheaper thus making it a preferred method of hauling cargo. We will never see planes capable of taking on the kinds of cargo payloads that modern freighters get on the open seas and rivers.
>
> For comparison, the [[largest cargo plane in the world]](http://en.wikipedia.org/wiki/Antonov_An-225_Mriya) can only
> haul 209tons. Compare this with the [new freighter just launched that
> can hold 19,224 67,200lb containers](http://www.shippingtribune.com/msc-sets-new-world-record-largest-box-ship-19224-teu/). To convert that for you,
> that's ~644004 tons.
>
>
>
[These were my original numbers. These will have to be adjusted as noted from a comment:
>
> The numbers in this post are misleading. The max deadweight tonnage of
> the new ship MSC Oscar is 197,000t (source: Wikipedia; "deadweight" is
> the total amount of cargo, fuel, crew, supplies, etc. that can be
> carried). Also, while 67,2000lb containers are available, a standard
> 20ft container is only specced for 53,000lbs. As you can see, MSC
> Oscar is specced for an average weight of 197,000\*2000/19224=20,500lbs
> per container. There are strict limits to how many "heavies" can be
> carried and where they can go in the hull. – @David Richerby
>
>
>
The actual tonnage capacity is 197k, however even being ~3x smaller than my original numbers, you're still talking several orders of magnitude of capacity difference between jets and barges.]
Even assuming cheap and abundant energy, the energy efficiency per unit of mass simply cannot be matched. An advanced futuristic society is going to understand this.
[Answer]
A lot of the answers here theorize about "When tech catches up", but remember there is many researches going on in the water craft area, when a plane becomes more efficient, the ships also becomes more efficient.
Powerful computers are used to calculate hull designs that is more aqua-dynamic. Engines are becoming more efficient, and motors are attached to convert wind and solar power to propulsion.
On ships there is installed computers with large servers that constantly feels the water, current, waves, wind and a lot of other aspects with high tech sensors, to make the travels faster and more efficient.
I therefore i think that it will take many more years than just 500 for other technologies to catch up with the water transportation.
Maybe if the polar caps melts, waterways would be even more attractive.
<http://edition.cnn.com/2015/01/16/tech/vindskip-wind-powered-container-ship/>
[Answer]
Besides being cheap and power efficient as most answers point out, currently most large cities are in river deltas. Therefore there are often ports to connect the cities to global trade routes. The rivers allow transporting goods to inland cities. And historically river delta cities had canals for transport within the city (for example Venice and Amsterdam).
[Answer]
>
> They are mostly used now due to large cargo space available per ship, and cheapness compared to air, but I would have thought that in a situation depicted here, we would by then have advanced past the slow, location-constrained, water-based methods.
>
>
>
Have you looked at the image? Where are these large scale air transports?
Instead all I see is a very limited number of small aircraft that appear to have considerable resources spent into minimising weight and maximising aerodynamics - not exactly a sign of cheap air travel.
Heck I even see windmills, which unless they are there for purely aesthetic or historical reasons indicate that the energy generation capabilities have not changed significantly.
[Answer]
A slightly longer response to a reply:
>
> You could replace 'shipped by water' with 'have not landed people on Mars' and there is no reason it should be a good bet to be true.
>
>
>
This is a disingenuous reply. Things we have done that we're no longer doing, versus things we've never done but are technically feasible.
We don't really ship by barge now. Erie Canal? D&H Canal? Superseded by railroad.
We *will* ship by sea, until there is a safer and cheaper technology. Nothing we've developed yet comes anywhere close to that mark.
We have taken the 'move by water' to the limits of what's accessible, and it costs too much to dig canals, compared to laying track (and railroad goes over or through mountains, and has a really nice network, at least in the US: home to 50% of all the track in the world, iirc).
Trans-shipping from big ships to smaller ships costs as much as trans-shipping to railroad, so we aren't doing barges (right now), and we won't in the future - if we continue to have the diesel to run the trains with (see peak oil). But we will be using ships, and we will still be using rail, until that mythical, cheap antigravity drive up-ends our technological transportation structure.
If we could move earth quicker, and more safely, and line canals - we might put sea access in a lot more places. But it would be huge waterways, that would handle Malaccamax, Chinamax or Suezmax sizes of ocean-ships, not smallish barges. And we might not even then, because unloading a huge ship requires some huge cranes and port facilities. Which is probably why a number of ports are having issues.
[Answer]
Tugboats pushing **little barges down little rivers** in a futuristic city **is** incongruous. Especially when there are no levees to protect against flooding.
Big tugboats pushing huge sets of barges down large rivers will still be quite common, though.
EDIT: "little barges" have been replaced by trucks and paved roads. The "huge sets of barges" on "large rivers" will still be there for the same reason that others have stated that cargo ships will still ply the oceans: cost when moving bulk goods and speed isn't a priority.
[Answer]
The fact that we would still be living on the earth 500 years later is almost impossible. Computation power is increasing at an unprecedented rate, and we might be living perfect lives 500 years from now. [This article](http://en.wikipedia.org/wiki/Technological_singularity) shows us that 500 years is far too wide a timespan to start predicting. For example, for a person living at 1515 AD, the concept of even hovering over the ground was unthinkable, today Voyager satellites are progressing to leave the solar system. The rate of linear growth in technology is growing, and I see nothing wrong in another hypothesis that we would be storing and using all the water available to us, on some place other than the earth. Maybe 50, or at the most 100 years would be a more realistic question to ask.
] |
[Question]
[
While on a space mission to Neptune, you accidentally broke your [tether](https://classconnection.s3.amazonaws.com/25/flashcards/3675025/jpg/a_dead_astronaut_in_space_by_sc0pe-141709EEA751A0EB56D.jpg) on the way. After a couple of hours floating, you were hit by an asteroid.
You passed out.
When you are conscious again, you met me. I offer to bring you back to your home with my ultra-speed spaceship.
The problem is, you don't have any pen, paper and no [Pioneer plaque](https://en.wikipedia.org/wiki/Pioneer_plaque) with you. You have to somehow tell me where to take you. I also want to visit your planet.
You know that for you to leave Solar System, you must have been unconscious for a long long time. You feel hunger, but not starving. Therefore, you should not be too far away from the place asteroid hit you.
You can see around, you can point the direction you want to go, and I guarantee that I will avoid any collisions on the way (so you don't have to worry about pointing at the right direction at a wrong time).
You need to observe your surroundings very carefully and tell me which way to go. But be careful, a wrong turn might get both of us lost.
**Some clarifications**
* Since your tether was broke, you only have what an astronaut brings out of space vehicle.
* You are able to show and tell, but not able to draw and explain the units.
* You need a **very** precise method to get back to earth. A common way to get lost is "I'll figure out how to get X when I get to Y."
* Even if you memorized the position of all planets during your mission, you have no idea where they are now because you passed out for some time.
* If you assume that you can distinguish the sun from that distance, then you also should show how (either a photo or some mathematical demonstration).
* Even if I know where the Earth is, I cannot know without proper observation. And I do not have that technology near me. Just like you don't have your technology with you to know where any planet is right now.
## More clarifications
* You cannot just say "go to Mars and we will find Earth. I have no idea what is Mars and what is Earth.
* You are near **Neptune**. Which means, until you provide a solid argument, I will assume you don't know where any planet is. That argument might be "I saw a picture taken by Voyager and in that photo Mars is seen like this." But I will not believe you if you say "I can 100% tell where Earth/Mars/Jupiter is." I don't want to get lost into Solar System.
* I do not have anything with me. You cannot just assume that my species invented any material for you to *write*. I even don't know this word. We communicate using brain waves.
* For the last time, **provide exact series of actions to go to Earth**. I will not accept "just go towards Sun, and it is the blue/third one." If you were in my shoes, would you waste your energy and time based on this vague description? I think not.
* You are an astronaut. Therefore, you have no pockets, no bags, **nothing**. This is how you Earthlings behave. We don't need no space-suit. You need. But you put no pockets on your suits. It is not my fault. So please stop telling me "it is very absurd I don't have anything with me."
* If you know where the planets are right **now**, then you need to **prove it**. You may assume that you passed out for a couple of hours or a couple of days, but you have to tell me **where is your home** based on your **current position** in space.
>
> To sum up, stop telling me how easy it is and point me the way!
>
>
>
---
TL;DR You are lost in solar system. How can you find where the Earth is?
[Answer]
This is a simple solution rooted simply in the fact that Space is really,
really big. In fact, have two solutions...
If you are hungry but not starving, you have been unconscious for a day or so, at most. Certainly less than 3-4 days, or you would have died of dehydration.
Unless the asteroid propelled you to super-luminal speeds or punted you into a wormhole, it is utterly impossible for you to be closer to any other star than you are to Sol. The nearest star to us is Proxima Centauri, at 4.25 light years away.
So, solution 1: Follow the radio garbage. We don't blast as much garbage into space as we used to, but we still toss enough out there that an extraterrestrial civilization could find us using it. In fact, we send out signals expressly for trying to say 'hi.'
But, supposing your rescuer only has short range communication system, Solution 2 is this: Step 1 "head towards the nearest star." Any ship capable of traveling through space must have the ability to tell relative distance to stars in order to navigate. And unless you were unconscious for at least 2.125 years while moving at light-speed....Sol is still the closest star.
Next, you may specify that Earth is 499 light seconds from the center of the star, situated within a 7.155 degree angle respective to the equator of the sun. This is enough to get you close-ish to Earth....though it's still a pretty large area. You might have to explain what our measurements mean.
Or you could simply explain that we are the third planet from that star, and seek it out together.
After that? Well....follow all the radio garbage, or look for the bright bluish 'star.' Earth is visible from Mars by the naked eye, so if you get within our orbital loop, you'll be able to spot it.
If you must point to get close to the star...well, with the amount of time you were unconscious...Sol will still be the brightest star in the sky. Point at that. Wait til it looks about the right size compared to how it looks from earth, then start looking for the bluish dot. And if, by some chance, another planet appeared brighter than the sun from the exact spot you started. Oops. Try again. It's not like you left the solar system or anything. From any individual planet, no other planet appears brighter than the sun. So if you stumble up to Jupiter or something...your next guess will be the right one.
[Answer]
First thing: **You were not hit by an asteroid.**
Space suits have *micro*meteorite protection, but understand the word *micro*. Any meteorite/asteroid which is able to knock you out **will rip you in pieces**. They are moving several times faster than a bullet.
If you must be unconscious, use a faulty valve which allows too much CO2 in your system, but not enough to kill you.
Second thing: **You cannot leave the solar system.**
Pioneer and Voyager probes were accelerated as fast as possible and they need *years* to get to the outer planets. So you will always see the tiny yellow ball which is our sun. It is also the only light source (not a reflector) which is not a dot, but a ball.
Third thing: **You cannot do wrong turns**.
Head for the ball with high speed and photograph the background. Only the planets will visibly move, the big bright dot is Jupiter. All planets move in a plane, the ecliptic. So you only need to get between sun und planet and head in sun direction, if necessary continue the search behind the sun. Now look out for a tiny blue ball. Earth found.
This is by the way the method you can find planets in *Elite Dangerous* if you do not have the equipment; they did it very realistic.
**Some clarifications about misconceptions:**
A handgun bullet travels with approx. 1000 kph (330 mps or 1/3 kps), a rifle bullet has approx. 3000 kph (~1 kps). To circle around Earth you need 8 (!) kps, to leave Earth you need 11 kps and to leave the sun from Earth's position you need 42 (!) kps. It should also be said that once a body reaches over 5 kps, its kinetic energy is comparable to the energy of the best explosives (meaning it does not matter if it is a shell or not). While the necessary speed is much lower at Neptune's orbit, it is still *several times higher* than a bullet ! And every body entering the solar system will be necessarily accelerated to such speeds. So yes, an asteroid/meteor who could knock you out is **deadly**, no discussion. If your ship/astronaut is fast, it either get hit much worse (wrong direction) or it does not get hit at all (right direction). That the speed cancels out that only a tiny, hurtful fraction remains is astronomically unlikely (you do not know the component of its speed apart from solar acceleration).
Second, the gravity well of the sun is massive. It has thousand times the reach of the Kuiper Belt so it really does not matter that we start from Neptune. As the highest rated answer says so wonderfully: Space is **big**.
[Answer]
Given the clarification in comments that this isn't meant to be about the language barrier, it's not terribly hard, even without being able to translate units (as the question specifies).
The question says a "mission to Neptune", but doesn't specify that I actually arrived at Neptune before the accident. So I'm assuming that I might be anywhere between Earth and Neptune, plus the (negligible on this scale) distance of no more than a week's drifting (given "hungry but not starving").
**Finding the Sun**
The Sun will be clearly distinguishable by its brightness.
Even at Neptune's orbit, while the Sun's disk is probably not distinguishable, the Sun will be *vastly* brighter than any other astronomical object.
(By the inverse square law, the Sun at 30 AU will be 1 / 900 of its brightness at Earth. This is still hundreds of times brighter than the Full Moon seen from Earth for example...)
**Finding planets**
The next step is to ask to be taken near the Sun. Without units, I can't specify a precise distance, but I can say to keep going until I say the Sun looks large enough. (This doesn't need any instruments to determine, as I know the Sun's apparent size at Earth will fit behind the tip of my thumb when held at arm's length; so I just wait until it's significantly larger than that.)
This gets me inside the Earth's orbit, which does two things for me:
* I don't have to worry about phase effects;
* I know I'm relatively near the Earth, within 1 AU plus my distance from the Sun.
The combination of these things means the Earth will be very bright - brighter than any real star. The constellations will look the same from anywhere in the Solar System, so the next step is to find Sirius (this is easy because it's next to Orion, which is very recognizable). Anything brighter than that has to be either Mercury, Venus, Earth, Mars, or Jupiter.
**Distinguishing the Earth**
The Earth will probably be easily visually distinguishable from the others by spotting the Moon - it ought to be visible from anywhere in this region (it will always be 'full' phase, since I'm closer to the sun. The Moon is a quarter million miles from Earth. At 200 million miles away, farther than I can be if I'm closer to the sun, that's 800 times the distance or 1 / 640,000 times the brightness. That sounds tiny, but 1/640,000 of a full Moon is still brighter than magnitude 2 - a relatively bright naked-eye star.)
**Fallbacks**
However, what if I'm incredibly unlucky? The Moon could happen to be behind the Earth or so close it can't be distinguished, or another planet could be right next to a reasonably bright star (so I see two pairs that could plausibly be Earth and Moon).
*No visible pairs:* Ask to be taken maybe 1/4 of the way around the Sun (the exact arc length isn't important, so units aren't necessary, this can be demonstrated with hands) and look at all the plausible candidates (really bright things) again. This should change the angle of view.
*Two visible pairs:* Check the colors of the brighter member of both pairs - if it's red (or orange/pink), it's Mars, so the other one is Earth.
If neither is reddish, it gets trickier.
-- For the Earth and Moon, there should be a quite obvious difference in brightness between the two members of the pair. The Earth is more reflective than the Moon, and it's about 4 times the diameter, so 16 times the reflecting area. This is a difference of *several* magnitudes at least.
-- The two members of the pair should be quite close. If neither object looks like a disk rather than a star\*, they should be within a degree or so. They should both fit behind a thumb tip at arm's length, or at least be very close to doing so.
\*If you can distinguish a disk, even a tiny one, you should be able to clearly tell whether it's Earth or not by color (specifically the presence of both very bright, white clouds and relatively dark, bluish seas -- Mars is reddish, Mercury has nothing that could be taken for clouds, Venus and Jupiter are all clouds).
[Answer]
I'm assuming I do not have access to a gravity based compass. That leaves visual navigation. I Look for the brightest point around you, all 360 degrees. here is the problem. I am far enough out that the Sun will be a very small bright spot, and I also run the risk that another planet of some sort with sufficient albedo might actually be brighter.
What's left? Prayer and Charades. I mime the sun then the orbit of each planet. Stress the third planet and then sequentially mime each planet's orbit until I get to Neptune, stressing Neptune's orbit. I then mime a line going from me back to the third orbital ring. I Hope like hell this makes sense to the visitor. The Visitor, if he has managed to navigate the gulf between stars, should be able to get the concepts of the relative orbits, will have a gravity compass or some such, and should be able to extrapolate from that that there is only one planet in the goldilocks zone in the Sol system and that I therefore should come from there.
Of course this would be soooo much easier with a bablefish.....
[Answer]
Reverse your trajectory. if you were hit by an asteroid - and somehow not pulverized - you are basically a cue ball on a pool table. Have the aliens go back along the vector you were on when they picked you up. That should get you back to within a few floating hours of where you started, which should be negligible by space travel standards. You can likely easily demonstrate this to the aliens with a simple demonstration.
[Answer]
Ok, first some assumptions...
1. You're alive and travelled in a Newtonian rather than Relativistic fashion
2. Your rescuer possesses, at the very least, the ability to operate an interstellar ship.
3. Your rescuer has sensory organs providing sight or a similar function.
Assumption 1 restricts the travel to an area within our Solar neighbourhood. I doubt you'd survive long enough to even reach the Oort clouds.
Assumption 2 provides that the rescuer understands the concept of a planet and understands that human-like life can't develop on anything other than planets in the Goldilocks zone, can calculate where that zone is, and identified the number of planetary bodies around Sol in the process of travelling here. Since we can do all that pre-FTL, a post-FTL civilisation would be able to as well, and also the most probably reason for a visit to Sol is to look at a potential life supporting planet.
Assumption 3 provides that the alien can see you moving and identify simple motions such as waving your arms.
So...
1. Point at me
2. Point at alien ship
3. Point at sky... I don't think you'd actually be able to single out the Sun from Neptune but the sky should be just fine
4. Mime a large circle in the air to convey that you want to go to a planet or describe an orbit
5. Tap something 3 times to count out which one I want to go to.
If he/she/it is smart enough to master FTL, that should be sufficient hint.
[Answer]
Go with the constellations
Ok so you don't have paper, but you can pee on the floor or something.
Take me to the place where I can see the big dipper, the little dipper, Orions belt, and Leo, Vergo, etc etc what ever you can remember.
You will need at least 3-4 to triangulate the position, but the more the merrier.
The FTL ship would then need to take the constellations and map them to get a pretty good guess.
Once your in the neighborhood, turn on the radio and follow the oldies station the rest of the way home.
[Answer]
Since, in previous answers, the respective authors took the liberty to modify the parameters in which the question was made, here's my take on it.
Why not take advantage of that situation. It's has all the conditions for a long and exciting adventure, between two potential friends, one helping the other find his/her home.
Good writing! ;)
[Answer]
I have no idea where the planets are around the sun. But I would kinda assume an astronaut might.
If I was taking a trip I would expect to have glanced at a map. (Possibly when trying to line up the radio to talk to earth) If it was a long trip I might even look out the window now and again and note some constellations and how they arrange themselves relative to the map.
Or if your spaceman isn't into science or looking at stuff; Astrology has that information per-compiled. I think we are in the sign of Pisces so I find its constellation and the Earth will be between that and the sun. And if our astrologer knew which constellation Neptune (it doesn't change very fast) was in it would be as simple as finding it and pointing backward.
Earth is 100 about solar diameters from the sun, but that doesn't help unless I have an idea how far out I am or I can communicate enough that the point is moot.
[Answer]
## Follow the *Galactica*.
But not all the way. It's going to veer off course to lead the Cylons away from Earth.
## Or give them the location
Tell them 93 million miles from the sun, third rock, between Venus and Mars, and planar with *most* of the other planets in the system. They should find it in one loop. It will help a lot if you can give them the units of measure in kilometers. They should already know it because everyone uses the Metric system. That will spare you taking your shoes off to explain what a mile is. If it helps, a kilometer is 1/40,000 of Earth's circumference.
If you find Mars, look for a functioning satellite and follow where the antennas are pointed.
[Answer]
Assuming your just barely out side the solar system, and not "far away". Then you just need the third thingy from the sun. The only one with H2O.
So,
O . . o . . . . . .
should work. Like my previous answer your don't need paper to make marks, just write on the walls with what you have on hand.
You can also do
```
O - OOOO - O
OOOO
```
Or
```
+-----E-E----------+
| +-------------+ |
E E NPNPNPNP E E
| | NPNPNPNP | |
| +-------------+ |
+------E-E---------+
```
Were also the only planet in the solar system with life on it, so you could go that route.
[Answer]
In [The Dish](https://en.wikipedia.org/wiki/The_Dish), the Aussies found the Apollo 11, which they'd lost track of, by looking near the moon. In this scenario, looking near the sun will work well.
[Answer]
If you know that you are somewhere near (within 1 light-year) of the Sun, then you can do this. The Earth is at distance of 215 Sun-radiuses from the Sun.
You can then identify the 12 star-sign constellations, then you can say that the Earth will be in a straight-line between the correct constellation and the Sun. Remember, that the constellation is overhead at midnight (and thus the one you want to pick), 4 months before the assigned birth month. Thus for December, you want to find Gemini or Taurus (and not Sagittarius).
] |
[Question]
[
In the TV show [Futurama](https://en.wikipedia.org/wiki/Futurama), an in-show infomercial mentions that Earthicans started dropping giant ice cubes in the ocean to slow down global warming. Now, Futurama is a show where science is a mixed bag: Futurama has a number of scientist consultants, but they also often send science to the back of the bus if it means having better jokes.
How feasible would this solution be in a more realistic setting?
[Answer]
# This will not work at all
## The short version
If you drop an ice cube into a room temperature drink, the drink will be slightly colder for a little while. But what happens then? Answer: the drink warms up again until it has the same temperature as its surroundings.
[](https://i.stack.imgur.com/oVh2V.jpg)
*What happens when these melt? Does the drink **stay** cold? No, it does not. ([Image source](https://en.wikipedia.org/wiki/Ice_cube#/media/File:Iced_tea_with_ice_cubes.jpg))*
## The long version
The issue with global warming is not that we are accumulating heat in such a way that if we can just manage to make a one-time dump/soak of heat, then we will be all right. It is not as if we are sitting on a warm rock that must just be cooled off a bit and then things are fine.
Four things to keep in mind for further discussion:
1. If you gain more heat than you lose, the temperaure rises. If you lose more heat than you gain, the temperature drops. If you gain as much heat as you lose, the temperature remains constant.
2. The surface where we live gain heat from the Sun and from the inside of the Earth
3. The surface where we live lose heat by radiating it into space
4. The rate at which we lose heat is **proportional to the fourth power** of the temperature of the surface
The heat that we gain is more or less constant, save for geographically local variations. This does not vary to any great degree. The amount of incoming heat is for all intents and purposes the same over the time-spans that we care about.
That we lose heat proportional to the fourth power of the temperature means that the temperature on the surface of the Earth will be very stable. Because if the surface cools, it radiates a lot less heat, and this is then balanced by the incoming heat, and will warm up the surface again. Conversely if the surface warm up it will quickly radiate a lot more heat. The incoming heat will not be enough to compensate for that which is radiated out, so the surface cools. So this is a sort of self-regulating mechanism.
The factor that messes it up for us is the atmosphere. The atmosphere is like a big blanket for the Earth. Some of the heat that is radiated away from the surface does not disappear into space but is instead reflected back to the surface again, the so called "greenhouse effect". This means an **increase** of the incoming heat.
Now if this reflection is constant, or changes only very slowly, the balance between incoming and outgoing remains constant and the temperature does not change very fast. We can adapt to any **slow** change. This is the way it has been throughout most of civilized history.
But if the greenhouse effect becomes more pronounced, and this happens fairly quickly, then more heat is being reflected back to the surface, and this upsets the balance. It is like swapping a thin blanket for a thicker one. Now we have more incoming heat than before, and this is not balanced by the outgoing heat. This means that the surface will warm up; its temperature will rise until there is balance between incoming and outgoing again.
Dumping some ice onto the planet will not help. While it is true that this will soak up some heat it is a very transient effect and will only cool the surface for a short while. The cooling caused by the ice soaking up heat upsets the balance between incoming and outgoing. Now there is a big difference between them, because the now cooler surface radiates a lot less heat. So the laws of thermodynamics will quickly restore the balance.
There is only one way that we can stop global warming and that is to make sure that more heat is dumped into space again. This we would do by thinning out the "blanket" that is greenhouse gasses (GHG), chiefly carbondioxide but also methane and some other GHG. We would thin it out by halting the emissions of these gasses into the atmosphere, and then let natural processes take their course, by which already existing such gasses are either broken down or integrated into sold matter, such as plant life.
Some suggest we can prevent also some heat from reaching us, with so so called [Climate Engineering](https://en.wikipedia.org/wiki/Climate_engineering), but those plans are... eh... "unsure cards" to put it mildly
[Answer]
## Comets are tiny
* Halley's mass is 2.2×1015 kg.
* A cubic kilometer of water has a mass※1 of 1 × 1012 kg
* Oceans hold 1.35 × 10 9 cubic kilometers, which gives us 1.35 21 kg of water.
* So, the mass of the Halley is half a millionth of the ocean. If it is 200 C colder than Earth oceans (say −180° C for the comet, 20° C for the ocean) when dropped, the calculus of how much would it cool the ocean is approximately as follows:
SpecificHeatice-180to0 = 180 K × 0.513※2 cal/K = 92.34 cal
[Enthalpyice](https://en.wikipedia.org/wiki/Enthalpy_of_fusion) = 79.72 cal
SpecificHeatwater0to20= 20 K × 1 cal/K = 20 cal
TotalSpecificHeat = 92.34 cal + 79.72 cal + 20 cal = 192.16 cal
All of the above values are per gram. This gives the approx. value of cooling as※3
EnergyChange = 192.16 cal/g \* 2.2\*1018 g = 4.22 × 1020 cal.
Which, with a specific heat of 1 cal per gram of water gives a temperature change of
TemperatureChange = 4.22 × 1020 cal × 1 K·g/cal / 1.35 × 1024 g = 3,125 × 10−4 K = 3,125 × 10−4 C = 0.0003125 C of variation.
## Comets are not (only) water
Comets usually have ice of it, but not only water ice. If we see the [Halley's composition](https://en.wikipedia.org/wiki/Halley%27s_Comet#Structure_and_composition), it shows things like CO and CO2 ice. So, while you may get some to reduce the heat by dropping it, you also get to release greenhouse gases to the atmosphera, somewhat reducing the effect.
## Comets have energy
Comets are moving at astronomical speeds, and slowing their mass will release energy as a lot of heat.
Even if we somehow "stop" the Halley comet to allow for it to slowly fail into the ocean, it will still have gravitatory energy. [Maybe it would be not enough to cook a steak](https://what-if.xkcd.com/28/), but it would still heat the falling water and the air around it considerably, reducing (if not negating completely) any possible gain due to the comet temperature.
## Comet will be in our orbit.
In order to drop it, the comet will have to get into our orbit. That means that the Sun will be warming it from some time, reducing the temperature differential.
Despite the popular image of an icy rock, when a comet approachs the sun it begins to melt and evaporate (in fact, that is what the whole "tail" of the comet is, gas and particles projected away from the comet).
Obviously, the "hotter" a comet is, the less effect we will get by dropping it on the sea.
---
※1 Water density varies slightly with pressure and temperature, but for comparing orders of magnitude the standard value is good enough.
※2 [Specific heat of ice seems to be](http://www.engineeringtoolbox.com/water-thermal-properties-d_162.html) 2,108 J/kg·K, or 0,513 calories
※3 Since the mass of the comet is nine orders of magnitude lower than the mass of the oceans, I would not change that value.
[Answer]
To me, it's the same as if you'd said:
Stopping global warming by leaving the fridge open.
1. Ice needs to be produced. This requires large quantities of energy for freezing water, which requires more and more power plants.
2. You need large quantities of ice. There are 1386 million cubic kilometres of water on Earth ([Wiki](https://en.wikipedia.org/wiki/Hydrosphere)), they need to be cooled.
3. Even if: You need to cool carefully. Just a few centigrade to low, will also have massive influence on the earths atmosphere.
So, maybe we should just be a bit more careful with this earth of ours.
[Answer]
@SJuan76 's answer is incomplete. He did the math to show the small cooling effect of, but didn't show the heating effect. I shamelessly copied his cooling numbers, and added heating numbers to compare.
## Comets have a small cooling effect
* Halley's mass is $2.2\times10^{15} \text{kg}$.
* A cubic kilometer of water has a mass of $1\times10^{12} \text{kg}$
* Oceans hold $1.35\times10^{9}$
cubic kilometers, which gives us $1.35\times10^{21} \text{kg}$ of water.
* So, the mass of the Halley is half a millionth of the ocean. If it is 200 C colder than Earth oceans when dropped, it would cool the ocean only by 4/10,000 C.
# Comets have a large heating effect
Comets have both kinetic energy and potential energy as they fall to earth. The Kinetic energy will be at least as much as the orbital energy of LEO. The Potential energy is equivalent to mass times gravity times height. However, since gravity is not constant coming from LEO, the gravity times height portion is actually an integral $$\int\_{surface}^{orbit} g(h) dh,$$ where $g(h)$ is force of gravity as a function of height. This function is $$ \frac{GM}{r^2}$$ where $GM = 3.98\times10^{14} \frac{\text{m}^3}{\text{s}^2}$. The radius or height of LEO is $6.671\times10^{6} \text{m}$ and the surface of earth is $6.371\times10^{6} \text{m}$.
Given the mass of the comet as $2.2\times10^{15} \text{kg}$, the potential enery equation: $$2.2\times10^{15}\int\_{6.371\times10^{6}}^{6.671\times10^{6}} \frac{3.98\times10^{14}}{h^2} dh.$$ I solve that to be $1.2\times10^{22} \text{J}$.
How much energy is that? Given a mass of the ocean of $1.4\times10^{21}$ kg and a specific heat of 3850 J/kg\*C, the heating due to potential energy is 22/10,000, or more than five times the cooling effect.
So basically, just dropping a comet from dead stationary in orbit, without any kinetic energy, will release potential energy many times more than the anticipated cooling effect.
[Answer]
**This approach is not only infeasible, thermodynamics says it wouldn't work at all.**
Though many of the previous responses are correct, there's a simpler answer that's been missed, though @Alexander von Wernherr came close:
>
> To me, it's the same as if you'd said:
>
>
> Stopping global warming by leaving the fridge open.
>
>
> 1. Ice needs to be produced. This requires large quantities of energy for freezing water, which requires more and more power plants.
>
>
>
Irrespective of the potentially negative environmental impacts of building more powerplants and burning more fuels to freeze water into ice, **cooling, refrigeration, and freezing do not result in a decrease in the overall energy of the system**. Your kitchen fridge works by pulling thermal energy out of the air inside the fridge, and dumping that thermal energy into the air outside the fridge. So leaving the fridge open doesn't cool your kitchen (the system) at all (and refrigerators aren't perfectly efficient, so they actually create some waste heat).
Even someone figured out a way to freeze massive amounts of water and deliver the ice to the ocean in a perfectly efficient way, their setup *must* do something with all the thermal energy they've taken out of the now-frozen ice! That may mean heating other, separate water, or simply exhausting hot air, etc, but the overall temperature of the Earth does not decrease.
Clever idea with the comets though; if they didn't heat the atmosphere on entry, enough of them could temporarily cool the earth, because they are a heat sink that is *exogenous to the system*.
[Answer]
If we drop enough ice to rise ocean level sufficiently (say 60 feet = 20 m), lots of prime ocean-front land will get flooded. Factories, cities, farms, nuclear power plants. **Raised oceans will also lift glaciers in Antarctic and Greenland** from the bedrock, and add all those cubic miles of the frozen water will slide to the oceans, **rising the ocean level on some 200 more feet** within months, flooding yet more cities and arable land.
Displacement of the population from flooded areas will result in **wars for territory, water, arable lands**. Inevitable changes of the climate will **decrease productivity of agriculture**, increasing the pressure for wars even more. Destroyed factories will decrease productivity, increasing the intensity of **wars for remaining resources** even more. Which (together with cancellation of many humanitarian projects keeping big chunks of Africa alive) will led to huge migration out from most affected territories, starvation.
More fortunate countries will close to any migrants. **Illegal immigration might become capital offense** resulting in summary execution on the spot.
All that fighting, starvation and killings will **decrease population substantially** and will slow down global warming **a little bit**. Not much, because positive feedback will **increase** global warming: all that missing ice in Antarctic and Arctic does not reflect sun's energy back to space but keeps warming Earth. And thawed permafrost releases even more carbon to air, and also methane, which is even more potent greenhouse gas than CO2. Which leads to the final frontier: melting [Methane clathrates](https://en.wikipedia.org/wiki/Methane_clathrate) frozen at the bottom of the oceans: [clathrate gun hypothesis](https://en.wikipedia.org/wiki/Clathrate_gun_hypothesis)
In fact, we don't even need to add any additional ice. There is enough ice already melting that above scenario is plausible in 100 years.
Also, it does not have to be ice. Rocks (or anything that can displace water) will do. For extra bonus damage to civilization, drop those chunks of ice or rocks strategically (in mouths of bays, don't waste them in the middle of the oceans), causing most possible damage to coastal cities by tsunami. Drowning millions of people, destroying all that production capacity and drenching arable land in salt water **will put some dent to production of greenhouse gases**, and will nudge civilization bit farther towards the collapse, for the final solution of the greenhouse problem.
You can play with increasing ocean level and flooding some areas on this map: <http://geology.com/sea-level-rise/> - lots of fun to be had! <https://coast.noaa.gov/digitalcoast/tools/slr> has more detailed maps (check flooding in your neighborhood) but max flooding is only 6 feet (geology.com goes up to 60 meters). Good enough for next 50 years, but we need MORE! :-)
[Answer]
# Yes. It's like dumping floating mirrors into the ocean.
* The white of ice cubes reflects light (read: heat energy)
* Part of the reflected heat energy would otherwise be absorbed by the dark blue sea
* Ice reduces the amount of energy coming into earth
* **You don't have to continuously dump ice cubes**
* **Thermodynamics have not been violated**
If you want to extend the effect, dump large ice cubes into the ocean - less surface area means more not-melted time.
# For every $O(n)$ ice cubes dumped, you get $O(n^2)$ cooling effect, because ice cubes don't melt at $O(1)$ pace\*. They melt at $O(\frac{1}{n})$ pace\*.
For all those who aren't computer scientists, $O(...)$ notation represents asymptotic pace;
$O(1) = 3$
$O(n) = 6x+6$
$O(n^2) = 8x^2+350x+5$
\*per cube. Really, they don't melt at $O(n)$ pace per $cm^3$ of ice, but $O(n)$ pace per $cm^2$ of surface area. The surface area of a $O(n)\space cm^3$ cube can be informally approximated to $O(\frac{1}{n})\space cm^2$.
# An extremely simple explanation
$h$ - heat in ocean
$i$ - heat coming in per second
We take freshwater and freeze it, dumping the heat into the ocean.
$h$ goes up by $W$ every time we put 1 cube in. $i$ goes down by $G$ for $H$ seconds every time we put 1 cube in.
We just need $G\*H > W$.
And don't forget that in reality $H$ is not constant, it goes down per the size of the cube.
$Find\space cube\space size \space s \space such \space that\space G\*h(s) > W.$
As if it wasn't obvious enough,
# Then continue dumping floating mirrors.
[Answer]
## Sort of, but not for the reason you think
One of the biggest problems with global warming is that it has an accelerating effect due to the melting of the ice caps. Since light colors reflect light while dark colors absorb it, decreasing the *albedo* ("whiteness") of the planet overall (melting the ice caps, for instance) will cause the temperature to rise faster. The converse is also true: making the planet whiter can decrease global temperatures. Since ice is white, artificially putting ice back onto the ice caps *can* counteract global warming.
Of course, there are practical issues with this:
1. You'd need a *lot* of ice. Much more than you can get from comets.
2. You'd need to reduce greenhouse gases anyway, or the ice caps would just melt again. Increasing albedo can help reverse the damage though.
3. Increasing albedo also has an accelerating effect. If you overdo it, you can create an ice age.
4. There are probably more efficient methods of [painting the Earth white](https://www.theguardian.com/environment/2009/jan/16/white-paint-carbon-emissions-climate).
[Answer]
**Yes, black holes can be cool**
To begin with, we will have to add [a mere $2.8\times10^{16}$ kg of ice](https://www.youtube.com/watch?v=fk9bKysYWLI) per year. Based on SJuan's estimate of $1.35\times 10^{21}$ kg for the mass of the ocean, this is just $2.07 \times 10^{-5}$ times the total mass of the ocean. Of course with the green house gasses still building up and increasing gravitational force from all the melting ice increasing atmospheric pressure (and thus temperature), we simply add more and more ice each time.
For the purposes of this calculation we presume that to cool the ocean we need the same mass of ice relative to the growing mass of the ocean each time. One solar mass is ($2 × 10^{30}$ kg), so the time before the earth's ocean is as massive as the sun is $\frac{log{1.99 \times 10^{30}} - \log{1.35\times 10^{21}}}{\log{1.0000207}}$ or 1.02 million years. At about this point the earth will converge to a *black hole* with a nice cool temperature round $10^{-8}$ kelvin - thus solving the problem **once and for all**.
[Answer]
**It won't solve the global warming**,
Because , to make those ice cubes , you have to cool water , to do that you have to reduce the thermal energy of the water and that thermal energy will add to the environment, so when you give back the ice cubes to the environment, it absorbs thermal energy which it output when making if the ice cubes , so the temperature will stay the same , in fact it can go up since the ice making process is not 100% energy efficient
**About comets**
This is not possible as well. Because when comets come in the direction of earth it gets heated up due to air friction. Even most of the metal comets get vaporized even before they hit the ground. In ice cubes case , all of the ice cubes will be heated water or steam when they hit the ground. This will make the global temperature go up.
**Mmm! what if a massive(earth size) ice comet fell down ?**
Yes. **Theoretically this can solve the global warming. 100% for sure** . But
Hitting this size of mass on the sea can make huge *tsunamis* and scariest part is the earth can be shifted from the orbit , even it can leave the solar system. Which will make it an ice planet. Eventually a dead planet. (Didn't even have to talk about what happens when it starts to melt)
[Answer]
To get rid of heat, you need to move the heat energy from the hot area to a cold sink. The heat energy the Earth is receiving is eventually radiated away to the cold and darkness of interstellar space, but since the Earth is an extremely complex and chaotic system (actually a series of systems like the atmosphere, the hydrosphere, the lithosphere and the ecosphere) there are no simple ways to map the various pathways heat energy arrives from the sun and departs.
What this really means is the heat energy in the ocean will only be temporarily diverted into melting the ice, but how it will affect the overall heat balance is not going to be predictable in any real or coherent way. A super volcano event like Tambora caused the "year without summer" by filling the upper atmosphere with aerosols, for example, but the resulting increase in smowcover or icepack did not start a global cooling chain reaction. Indeed, the only way we know for certain to cause such events as the "Little Ice Age" involve a reduction in the Sun's output, such as the Maunder Minimum between the 1400's and the late 1700's, or the current apparent reduction in solar activity which is happening now.
Warming periods are less predictable or explainable, the warm weather enjoyed by the Roman Empire or during the European Warm Period don't have an evident cause that we can point to, for example.
If the goal is to cool the Earth, the necessary thing to do is change the heat balance. Since the "cold sink" is already at an unvarying 3K, the place to interrupt the heat flow is to block the Sun with an orbital sunshade, perhaps at the Earth Sun L1 point or having millions of small mirrors orbiting the Earth (Injecting aerosols into the upper atmosphere, while known to work. would not be a quickly or easily removable as needed).
[Answer]
All the other answers deal with physics and thermodynamics and ignore the root of all evil - Money.
There may be an issue of ownership - Halley would surely have a word to say about reuse of his comet, were he still alive.
Since he's not alive, ownership will pass to his descendants, who have to be located and queried. Given that Edmond Halley was English there will be a reasonably-sized Compulsory Purchase payment due to Halley's estate
Refer to <https://en.wikipedia.org/wiki/Compulsory_purchase_in_England_and_Wales>
In short - complex finances could kill this faster than the consensus that it won't help anyway.
[Answer]
Build a really big orbital beanstalk.
Catch ice. Raise (warmish) water and lower near-0-K ice, trading their KE with minimal friction.
Build large glaciers from this ice, increasing albedo of Earth.
This both lowers the current temperature of Earth, and makes it reflect more light. Between the two, at huge scales, you could actually cool the Earth.
The fact that the icebergs melt is unimportant, because you are refreshing them at whatever rate required.
Obviously painting the entire oceans white (covering them in ice) would be sufficient to outdo modest global warming.
The energy required to do this is all in orbit. And as we lift as much water as we lower water, the process is mostly a closed system; you can even bag the water you raise up before you freeze it in orbit to reduce sublimation losses. You basically are building a giant refrigerator plus coating the planet in mirrors.
At the scale of Futurama tech insanity, this is mild. At any reasonable scale, it isn't.
[Answer]
# No, or at least with ice (snow)
After read the [SJuan76](https://worldbuilding.stackexchange.com/a/64020/35041) and [kingledion](https://worldbuilding.stackexchange.com/a/64036/35041) you can notice that it's almost impossible get colder the planet using comets. A comet has very low water compared to the entire oceans so the change of temperature they do is impercetible.
Also, you can't cold directly the planet making ice because to cold an object you have to warm another (transfer heat). Maybe you could transform thermal energy into electricity but that can't be done at planetary scale.
But....
# What if we freeze water in order to prevent future heat and not to reduce the actual heat?
Before continue I have to say:
1. This obviusly can't be done at planetary scale, or at least with our technology.
2. **We won't use ice**. I hope you won't mind. Well, we **can** but it would be better not.
Do you have read about the [Albedo](https://en.wikipedia.org/wiki/Albedo)? Well, you should do.
>
> Albedo (/ælˈbiːdoʊ/) is a measure for reflectance or optical brightness (Latin albedo, "whiteness") of a surface. It is dimensionless and measured on a scale from zero (corresponding to a black body that absorbs all incident radiation) to one (corresponding to a white body that reflects all incident radiation).
>
>
>
Each material has and albedo value:
[](https://i.stack.imgur.com/uEAJj.png)
With this we can know that some materials reflect better the light of the sun (heat) and it escape of the Earth.
I've found some values over the Internet. I'm not sure which of them is more precise so I'll use all of them:
$$\begin{array}{|c|c|}
\hline
\ \text{Sustance} & \text{Albedo}
\\ \hline
\ \text{Ocean} & \text{%}5 - 10\text{%}
\\ \hline
\ \text{Open Ocean} & 6\text{%}
\\ \hline
\ \text{Melting Snow} & 40\text{%}
\\ \hline
\ \text{Oceanic Ice} & 50\text{%} - 70\text{%}
\\ \hline
\ \text{Atartica Snow} & 80\text{%}
\\ \hline
\ \text{Fresh Snow} & 80\text{%} - 86\text{%}
\\ \hline
\ \text{Freshly Fallen Snow} & 90\text{%}
\\ \hline
\end{array}$$
Firt we have to know the actual heat that it's absorbed by oceans, and the amount that it's reflected.
$$\frac{\text{Ocean surface}}{\text{Earth surface}} = \text{% of ocean surface}$$
$$\frac{361,000,000 \text{ km²}}{510,072,000 \text{ km²}} = 70.77 \text{%}$$
So the $70.77 \text{%}$ of the Earth surface is cover by water.
We know that [solar constant](https://en.wikipedia.org/wiki/Solar_constant) of light in the atmosphere is $1,366 \text{W/m²}$ but at the surface only reach $1,025 \text{W/m²}$ (I won't count clouds).
So:
$$361,000,000 \text{ km²} \times 1,025 \text{ W/m²} = 370,025,000,000,000 \text{ Watts} = 370.025 \text{ TW}$$
If we substract the values of the albedo (that power \* albedo value) with the total energy we can know how much energy is absorbed and how much is reflected:
$$\begin{array}{|c|r|r|r|}
\hline
\ \text{Sustance} & \text{Albedo} & \text{Reflected} & \text{Absorbed (Heat)}
\\ \hline
\ \text{Ocean} & 5\text{%} & 18,501.25\text{ GW} & 351,523.75\text{ GW}
\\ \hline
\ \text{""}& 10\text{%} & 37,002.50\text{ GW} & 347,823.50\text{ GW}
\\ \hline
\ \text{Open Ocean} & 6\text{%} & 22,201.50\text{ GW} & 347,823.50\text{ GW}
\\ \hline
\ \text{Melting Snow} & 40\text{%} & 148,010.00\text{ GW} & 222,015.00\text{ GW}
\\ \hline
\ \text{Oceanic Ice} & 50\text{%} & 185,012.50\text{ GW} & 185,012.50\text{ GW}
\\ \hline
\ \text{""} & 70\text{%} & 259,017.50\text{ GW} & 111,007.50\text{ GW}
\\ \hline
\ \text{Atartica Snow} & 80\text{%} & 296,020.00\text{ GW} & 74,005.00\text{ GW}
\\ \hline
\ \text{Fresh Snow} & 80\text{%} & 296,020.00\text{ GW} & 74,005.00\text{ GW}
\\ \hline
\ \text{""} & 86\text{%} & 318,221.50\text{ GW} & 51,803.50\text{ GW}
\\ \hline
\ \text{Freshly Fallen Snow} & 90\text{%} & 333,022.50\text{ GW} & 37.002,50\text{ GW}
\\ \hline
\end{array}$$
Water is about $70.77 \text{%}$ of the surface of Earth, now is your mission determine if changing the albedo of that surface (turn water into ice or snow) would reduce Significantly the heat of Earth. I think yes.
I am not sure but I think human contamination increase the amount of energy aborbed by $+0.2 \text{ W/m²}$, with a range $+0.1\text{ W/m²}$ to $+0.4 \text{ W/m²}$.
So human contribute with $102,014.4\text{ GW}$, with a range of $51,007.2 \text{ GW}$ to $20,402.88 \text{ GW}$. If you freeze the oceans the new albedo gain would counter-act our actual contamination.
[Answer]
**It depends on the ice composition, amount, and where you release it**
Current theory is that the previous ice ages were caused by large amounts of glacial ice being dumped into the Mid Atlantic Current, shutting it off sporadically and preventing the equatorial oceanic heat transfer to Europe and Canada (the main reason England is so rainy and warmer than its latitude should indicate is this effect).
Dumping a large amount of freshwater ice into the region occupied by the Mid Atlantic Current could replicate this effect.
link: <http://www.sciencemag.org/news/2016/06/crippled-atlantic-currents-triggered-ice-age-climate-change>
The time period would probably be shorter than normal, due the the same effects others have described, since we have too much heat trapping gas in the atmosphere.
Another interesting tidbit is that historically the southern hemisphere cools when the northern hemisphere gets warmer, and vice versa. Right now the ice sheets in Antarctica are actually growing (link: <https://www.nasa.gov/feature/goddard/nasa-study-mass-gains-of-antarctic-ice-sheet-greater-than-losses>) and this is one of the main talking points for global warming skeptics due to this historical pattern.
Edit: Wow this thread got necroed from last year, didn't even notice.
[Answer]
Entropy will mess that all up. While the ice could lower the temp. barely, eventually the ice will melt, causing higher sea levels. Plus, think of it as percentages. In school if you get something lower than a hundred, your average grade will never be exactly %100 percent ever again until it's reset (but you can't reset the temperature). So then, once its water, you cant change it back. If then you take the water and put it in your freezer, the freezer outputs heat through its back, causing equal yet opposite heat. Entropy is inevitable, so there isn't much of a solution.
[Answer]
To put things in perspective, the volume ratio of water ice on Earth to ocean is approximately 1/43,750,000. If all the ice on Earth melted (which it may yet do), it is the same as placing 1 gallon of ice into a lake containing 43.75 MILLION gallons of water. Can you picture it? Now imagine you had a thermometer in one end of the lake, and it read 80o F. Just how much do you think that thermometer would change, if you dumped one single gallon of ice into the lake anywhere away from the thermometer? Can you imagine it? THAT non-change is what will happen to ocean temperature if all the ice on Earth melts ... nothing! Ocean temperatures worldwide will not change more than a tiny, tiny fraction of 1 degree! Then, they will warm right back up ... probably within weeks. Sadly, the only way to stop this catastrophe is to STOP burning fossil fuels.
] |
[Question]
[
Enchanted jewelry is a major mainstay of basically any genre of fiction involving magic. It comes in many forms, but the concept is the same: wear it, and it gives you certain powers or protects you in some way.
Which got me wondering: there are *lots* of varieties of jewelry. Rings, bracelets, necklaces, crowns, tiaras, piercings of every conceivable shape, size and location... there are a plethora of forms that enchanted jewelry could take. But they aren't remotely created equal when it comes to how convenient it would be to wear them and keep them on in a combat situation. Assuming that the size and shape of the specific piece of jewelry isn't pivotal to holding that specific enchantment, most of us would rather, say, go into a fight wearing a +5 magic ring... than a +5 magic 5-inch radius *nose ring*.
If we define jewelry as a combination of a gemstone and a piece of metal that is worn in such a way that it makes physical contact with the body, what form would enchanted jewelry take if it were designed from the ground up to be practical in a combat situation? The way I see it, we're looking for a good mix of three things here:
1: Low inconvenience to the wearer while worn
2: Low risk of falling off in intense situations
3: Ease of switching out for other enchanted items as the situation might demand (so nothing surgically implanted completely inside the body, for example)
**With these things in mind, what would be the most pragmatic design and location for enchanted jewelry?**
[Answer]
# Dermal Piercings
[](https://i.stack.imgur.com/om7XZ.jpg)
The classic dermal piercing consists of two parts, a fixed **anchor** that is inserted beneath the skin, and a replaceable **top** that holds the decorative part (and any gems).
[](https://i.stack.imgur.com/hnU9Dm.png)
## Unique Advantages
* **Sizing isn't an issue**. An army can standardize the size of the base, and *any* topper will be guaranteed to fit. In fact, an entire nation could standardize. I think this is the biggest selling point. Interchangeability is *huge*. Imagine if we had to make a different gun for every soldier!
* **Impossible to steal unnoticed**. The base can't be removed without a scalpel, and the top needs to be unscrewed while applying considerable pressure to the surrounding skin. They can be torn out, but even that's hard to do, because they're small enough that getting a *quick* grip on them is very hard.
* **Unlimited quantity**. You can have as many as you have skin to fit them in.
* **Flexibility of display**. They can be concealed or shown off, as need be: visible ones on collarbones, necks, and wrists, hidden ones along the sternum, or beneath the ribs. Hide your dangerous ones and show off your innocuous ones to look non-threatening. Swap them around to encourage people not to fuck with you.
* **Logistically convenient**. They take less material to produce than almost any other option. They're easy to store and transport. A box of a thousand toppers and anchors would weight barely a kilo and a half, and use about as much raw material. They're fast and easy to produce, and can be produced using assembly lines.
## Fulfilling Criteria
>
> 1: Low inconvenience to the wearer while worn
>
>
>
They're functionally weightless, can be worn under clothing, under armor, and in the nude, and don't interfere with movement. It hurts a bit to bump them hard against something, but that's a minor and occasional discomfort, with careful placement.
>
> 2: Low risk of falling off in intense situations
>
>
>
They literally can't. Dermals may reject over time, and can be torn out, but will never fall out without warning on their own.
>
> 3: Ease of switching out for other enchanted items as the situation might demand (so nothing surgically implanted completely inside the body, for example)
>
>
>
Couldn't be easier. Unscrew one topper, put on another. Takes as much time as twisting a bezel on a watch. If you have dozens, it might take longer, but *per unit*, they are faster than rings, necklaces, gauntlets, or standard piercings.
## Advantages over other options:
* **Rings** take time to take on and off, interfere with any kind of manual labor or combat, get caught on gloves, can get stuck, cannot be exchanged between users, and may *stop fitting* over time. They are always visible.
* **Bracelets** and **cuffs** take up space. Loose ones will dangle and catch, tight ones will chafe. Sizing is, again, an issue.
* **Necklaces** tangle, catch, and twist. The chains are either heavy, or fragile. They can be easily grabbed and torn off (or worse, used to choke you).
* **Standard piercings** have more limited areas (there's only so many places to slip a piercing through) take longer to swap, and are less universal (an earring, a prince albert, a nipple piercing, and an industrial piercing are all non-mutually exchangeable)
* **Chainmail** isn't appropriate for every occasion, is heavy, expensive, and cumbersome, lacks flexibility1, takes time to take on and off, is hard to store in bulk, and is essential but time-consuming to fit to size.
## Disadvantages
* **Infection/rejection**. If you don't have healing magic or an understanding of germ theory in your world, don't even bother
* **Up-front installation**. While dermals take vastly less time to produce than any other option, a user would need to have anchors installed ahead of time. Most piercers recommend only getting 3-4 piercing at a time, at most.
* **Squeamishness**. This is entirely a cultural thing, and you could handwave it, but some people might be uncomfortable with piercings.
---
At asker's request, I'm adding a collage of a few recommended locations.
[](https://i.stack.imgur.com/xbduO.jpg)
Places to avoid: Hands, fingers, legs.
---
1. Yes, you can move in it, I've done an obstacle course in it, it's still a pain and far less flexible than ordinary clothing.
[Answer]
**Necklace**
Let's look at modern soldiers. Rings typically must be taped over to reduce the risk of getting caught on protrusions, bracelets and earrings are a complete no-no for the same reason (except small studs), yet the one thing that most Western soldiers are required to wear on the battlefield are dog tags. These are worn on a breakaway chain around the neck, so that if something goes horribly wrong and the chain gets caught on something then the chain will break in preference to the neck breaking or strangulation occurring.
While in combat the dogtags are under both clothing and body armour, preventing the chain from catching on anything and making it effectively impossible to remove them unless the wearer is either cooperating or incapacitated. When not in combat the dogtags can still be worn at all times if necessary, even while bathing if necessary, as the chain is loose enough that it can be moved to wash the skin of the neck and chest. This means that while it may be more comfortable to remove the dog tags / magic necklace, if the protection provided is essential then it can be worn without ever removing it. (I really like the idea of Rubrikon's jewelled gauntlet, but I can't see anyone being able to wash their hair while wearing it.)
In summary - if a breakaway chain around the neck works for modern soldiers with dogtags, it should work just as well as magic jewelery.
[Answer]
# There is likely nothing better than your classic ring
Rings have been worn since ancient Egypt, and thus we have plenty of experience making comfortable rings that won't fall off easily. If well fitted, they can be easily worn/removed in a single movement. Even limiting yourself to one ring per finger, you can wear ten that can be easily swapped out if you have two free hands, and can be done with a bit of difficulty with one hand otherwise holding something.
But, as the image below shows, you can wear multiple rings per finger, although this might turn into a weird Tower of Hanoi game if you need to swap the ring closest to your hand.
[](https://i.stack.imgur.com/dGy0Q.jpg).
[Answer]
Huh; the story *I'm* writing had to address (almost) this exact question. So I'm going to adapt the answer I used, and suggest...
### "Pandora" bracelets
You want convenience; something that is easy to put on or take off. You want it to not get in the way too much. You want something small, that makes it easy to wear several spells; this is where you get "beads". The bracelet itself may or may not have its own enchantment; "don't fall off in combat" would be a good candidate! ("Don't let me be removed without my wearer's permission" is another good one.)
Each individual spell item is a small bauble that can be securely attached to the bracelet. The bracelet itself can easily be snug enough that it can't fall off accidentally (handcuffs are a thing, after all).
You probably want the bracelet itself to be durable. Ideally, you'd use an all metal band with something like a watch closure, but that requires a certain level of manufacturing ability. In a pinch, you could use a strung leather cord tied to the wrist or ankle. (I don't recommend the neck due to the possibility of it becoming a choking hazard... unless you can enchant against that!) Lacking modern manufacturing, however, chain mail is going to be harder for an enemy to cut off.
Now, that said, I'm using spells for mundane/domestic purposes. If the spell-wearer is expected to be physically mixing it up with enemies, or if you're otherwise worried about the bracelet getting snagged on something, you might want to consider cuffs (or bracers), possibly worn on the upper arm. Again, the interesting idea is to have something that holds a number of spell baubles (they come in standard shapes, right?) against the skin. Alternatively, you could just wear a long glove *over* the bracelet. (Or, if it's on your ankle, you might *already* be wearing it under a boot and/or sock. Secure, inconspicuous, but takes maybe a minute to put on or take off, compared to a few seconds if it's on your wrist.)
[Answer]
A ring comes to mind of course. It's unlikely a ring will fall off unless it's ill-fitted. It's also really convenient to put on and take off when needed.
Alternatively a cuff bracelet may also be a good fit.
[](https://i.stack.imgur.com/jMqQH.png)
Personally, I would go all the way and wear a jeweled gauntlet.
[](https://i.stack.imgur.com/xVjZ9.png)
[Answer]
**Ear rings or other piercings**
Most answers here are seemingly stuck on the stereotypical magic rings, amulets etc.
But the most convenient answer would be an earring (how do you spell that?) or other piercing.
* **It always makes skin contact**. Depending on how stringent the rules of magic are, amulets, neclaces or the pandoras box answer can have seconds in a hectic fight where the jewelry has no skin contact, which could be devastating. Piercings are always directly on (and in) the skin
* **Very safe**. Piercings are usually located in places that are not likely to get caught on anything (like rings or wildly swinging necklaces). They are in places where you have other problems if a weapon reaches there.
* **Moderately convenient** they don't weigh a lot and can be taken off/switched out fairly easily. Just making a new "slot" for that extra jewelry need a new hole. However, [you can have more or less infinite pieces of magic jewelry attached](http://data:image/jpeg;base64,/9j/4AAQSkZJRgABAQAAAQABAAD/2wCEAAoHCBUVFBcVFRQXGBcXHCAaHBcaGh0aHRkXGhodGhodHCAdICwjGh4pHhgcJDYlKS0yMzMzGSI4PjgyPSwyMy8BCwsLDw4PHhISHjIpIykyMjQyLzI0MjIyNToyMzIyMjIyMjI0MjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMv/AABEIALQBGAMBIgACEQEDEQH/xAAcAAACAwEBAQEAAAAAAAAAAAAABQMEBgcCAQj/xAA/EAACAQMDAgMFBQUHBAMBAAABAhEAAyEEEjEFQRMiUQYyYXGBQpGhsbMHFCNS8DM0YnKywdE1guHxJGODU//EABkBAAMBAQEAAAAAAAAAAAAAAAACAwQBBf/EACYRAAICAgEEAgIDAQAAAAAAAAABAhEDITESIjJBBHETYTNCUZH/2gAMAwEAAhEDEQA/AOzUUUUAfKy37R/+n3fnb/VStTWW/aOJ6fd+dv8AVSqYv5F9k8ng/o443b5CmHTbcncT9PWqVtQVzyOKbaC1AB+H+9epklUTLgjci05hTEeoPpWdv9eIZ19wqCysZYEhTAAUYJI2g8ZkmKc9Vu7UM4ERjnNc+1T+c5ntz8+/1+VeRlqb2epJ9KSR6uPuMiQWJYyZzPaBgfCTTPp9sDkmfQAH5Se3/qlem5meTE056fZBMEg8kAxn1OTxzzWefFHcZofZtNPce4l17ihFDLEneWxmJA/M7TUum8Fxcc3NqKQu2HBaTCeGYGSzHcOyr3kmp9A9y3pLgRYuG47W3tqXBZGNu4zbsFVQKykgHc+MkxNcVbdkbdh3HygDcfCMMSPKAC3h228sznsIqMqRog7T/YitWRv4JJaFyQuJIiQPLCrkgcxE5rWaC0n8NAyESCYbbB3RjuWwfd9SDFZO51YBv7Nip5IgHaZBADDyniTnt8ac6DqllSD5liFypCAqSYIWYBGTEzBmextq2CSUqTNFoNA9zUEgFUBjI3Qpk7Vn4xzxmmvWLwtqVDsWGRtUkGAY3GCA3mnHcZ7RX0PWNGIC3JcjzKUi4ZnyghdxI24UZyPpNf6kpULbFxlPwYAiIUywZjnt8u2aqmox/Yj7pV6IH1hhnbabagKfOm3AK7mPBALqCO8rVPT661dZLalEDKzG4zLIhoUELhmPmxMiT3EVFrGe4WSG2lYNvZta4xBdFR2hA38OIMZSTOBS3RdSt3Wtae3jfaMlgWbxdrsTbESg8xJ4J4rlpxv2cfVGVDqwV2+JbCkkBQSLhUg+UbVKFieYI4g+hldqC5JDfAkwWiOZjIBUCZXir/7uqWTba2XvyWZ9wgcgFmzsUCPLnbiCRmlzpfKSVXDDzmHkTtB8QBgozGY4M8VGcX6KQarYv1+lXYrNtg58suDtAAMxiQ3HeD3GVT29wxHm4jIxECfQk9+aZXtQM7zAPvLMAjg+6dpAidwmaW3LwQiTK/ZYgEf5TGCREfh2zwBfrk8qqTuIB7f7d5iPuquF2hYn4Y+Ug/Dn7qY3nLwACv8A/TI2tBlYgCO3z/CvC21LGA2Yxhf5Zxkck5+XFWjKlszyhctEnUX/AIIOTIyPU8H48yabdJ0NrT6ZruouruNtkt2QAWG9QQ5bmYM4gCe5IAQ9dwgMe9E94IBEn5146MLDpdW9uW7sJtuDiVBO1wfeXEfU0QWrCb3QmsuJAYjtwJM/81qeiXkF63C7YG2CZme59DWUNpuQfj8u05q1p9U1twRmM5/rNaCcNSTO76AnaCTWb9sdCAwugYbBI9fWnHs5qN9hDVvqunFy0yxPcfStGOVUaM8OtNHLGXJkwfWurfs+n9xtz/Nc/VeuU69Crma6t+z3+4Wvm/6r1o+T4L7PKxKps09FFFYTUFFFFABRRRQB5rMftGaOn3T8bf6qVp6y/wC0j/p93/Nb/WSqYvOP2TyeL+jkmnVdpMHmnWiIKTGDSjR2zJFP7NoBQB2Fbc8tHPiQt2J+s22a2QcmDzgR8I+f4VjrtgmFtq1xmAnarFs/ZgTuGOfjW/17AKQeCOfh/X50p6F1k6S3qGtW9912ROCStpxcXyxBB8Q2x/3D6edNm3LDSZkUt7SAcEcg4MjkH0j40/8AZrpov3kQTBMtLMsrMEAznBjGYLHgYtdI6ej6kW7xcCTuuIAxa6OZYggjeTJjvukc1rOldCAtWWW4viXHgonYM5QuI5G0CZ+yT61mnIaCPvX7jLpdLcSQLYuKri3HkBADAOQyEeWCQf5szVfW2LYtWnXUW7jXEzLjysAIXzHzmMBe23iIqz7dacWnRG2pbcXGXbMEswZ5BMbhu5HY/Cs54Zsotw7mU+QOGyjA+6V5UwQfjkdqk+KaHgmtp6K+ltQ5Q3EJkHkZESV3MZPBx3OM8VrvZ0XbVuAd4uuoAH2HGZnlN25lgrwnpWTL2xIBuyMkSo/nJCxBb3WlhMGJ9K0+m0dkWUc+LcIKna7tu5Alo27eQBByJj49jfJ2TV0adOtMzOl23ftEYBSwbgAAKuXIRlIDZkGIIwM0kvdVIuWvE1N0I7bSXtlHC52ttW2FzjifWrmis27ilraXEAENcF11TxMMwb+IZXIjPMTNSa7W6fYVNy0xbOSLjCJIEMDGcTzx64eUk1bEjFp0hZf17OxuNcuLbVxL7WzbDD3wphgVAwfjUN3qly3ctvc223DqGGxS9xQNiOrE7riyzCYB9YJgfOue0loIbXmLbC6nagU5BAhveM4gdgaWdUv+JZXxG8RmXcCV5VpIgcgdvpU7pFKTdG01/SkCARvuAApbMAMd0XPN70GZIYkCPSst1dyhK3LaJAEKu8LcGD5W3GHCjgg4aSOBTjS3m1KaYqh2okF5+15Q6OY/mC4xOM5qL2g9ntu24HVRcJDoVLKSMDHAG0TEfzZzQmt6F3rZl9AuDvQbHRwrNMhsFWhT7oJWSAeSYJELG1s21xc58pUeZWQg5kgrHYE582IjDi5onwFFpyY8o3OXj1VoMAfywMcwKsLZslbgvW9rrbBUW7hGTsZeTEfxOCOFHOKNvg60lyZMJg4CkR9pQSSdvuky2T2B9TXuyn2lJgiMkFlAmQ0RGRORxFQ6+y0gECee8HB+OKnt3lCj17/OY788TXG9aCt7KPV7xYER3/EjNKdN5HHxnB7/AO/9CnWrYQR3P1JwcfeZ+lK7gKMwO0+hBEfMHv8ACPWr43qjPkW7BHEmfXb+Mcj+sUasidw9K8qoPcf13/CpLqTCmJIgfGJqqJHVPYDVFtMsiIx9OK1lYr2GfbZRTjGexrZIZAqsGbWtWc79qtJsuGByZ++t/wDs9/uFr5v+q9Zv2100qHHb8q0v7P8A+42vm/6r1oyO8S+zzZR6crNNRRRWUoFFFFABRRRQB8rNftBt7tBdH+K3+qlaWs17fmNBdPxT9RafF5r7Fn4s5dokiF706K4pV0kBth9MU4cc1pzPdFvirtsS9YODjtHyqJdumtjahuMt61c1LpcHhsgJNq2CwB3BnE7ZEwZMDbZ1ibsDJJ4PHxJ9BSTrNk29Tc09q4xtkqpESGZUVZK5EBixB7SOCATgm9mjN6RW6rrRc1DtaTwA7e6jwiCRgEAbgCASOJ7cRrul9Zu2WOkFsJeV1VYMqbgd0cSx+1uBBHcKDWUuohO26hDZG5RtDoMGeN5BPJyODxV7qHVmurbsozu7Id7Ha7b2IeUwCDuBnngR3mUoN1RJSSsc9V9vWNy+nhK+0C2pKkstxGJaMHb5iRP/ANYj1Ga1PVm8Ni1m0N2Vbe+4MoB7NDQDwwI5qqnR2KC4kP3lMklvUHsRB++q923KGVgqdpAUgqoB3mG9ABnsfSmcK0xYyvaLWm6nc95IAQDIGfsjjI3HbzyYOea0fTut6gAFUtvJJ2kAg7iGec43ED7hzWR6fYDNtU4nynAJ55AJz3j8+K0vStK/mUesRtkAxuJkINvr/wAwalLT0aISbWxjoeqkITvUmWNyyVdAgU+VokhpA7THBxz9Ote5hjaRQIg7mLSRc3MV8MiIwZja0QRkoNcC5AVi59fSfWR8+1fCLzOCLYSMjbKBcD3drbhIz732jSp2Ehv1HSeRrx/d2W3A8ouQCRIG9Lm0nBzkY9Kl6h1q22nsi1YEqqhzuPmYlQG8mD3jPfjis2lrUIjr5wj4YgsoYAAhXM7XXvGYM0y15dk8S5dUvc96FQhipkEBQJmTyO/yqvTSI9Vst9P9svC1bXAn8O9BuID4SLcEAuoMgYDSDzNbHqHW1bS/vCkFcBdpLJu3HcO0YAjGJ/xGOfXrrahbXiqpFu2E3IoRoEIm+IL4CwQDAImr3RL9uBprhuBG2gkvgefcIBQxC3G4PqcnBSUUx4to0/UBYum2qMzltrboxvJMBTOfdOYxA5mver6YSxtXFS26BbgdnAD203+QkckG7gdsfCkep0YSFtlvfDDZMkeY7UBHkAElZ4+MGrHs5q3uawJcQXLrJuBJY+ZFyxLZBIXbJx5gIEmkUV6HcpLkW6tBO0nJkzGREnH1Iikjyo2EnbJO2THcTHr8fp2p0qk7mYCCcDjAxk+uKW9StwAZnOMf16f1zUounRWe1Yua5nn/ANfQ80MA+SPlwP65qN1+H38fCgtH5eoz861RMkkQtajsY/CpNBpjcdBujOWP2cn+vpXq+8xgzziB8xU1qEUJI3PG7/CD2+ZVvzqsST5N77P9WS/BXDKdkx7yxgn41stM+K5v7JOAFWZZSZPAjgflXQtK81ZcmvDuCIPaG1utmmPsIsaK2P8AFc/VeoOoJutsPhVv2LSNIg9Gf9RqeT7K/Zmyx77H9FFFSJhRRRQAUUUUAfKzP7QlnQXR6tb/AFUrTVl/2if9Pux62/1Up8XmvsWfizmfSG2kAetOtQRB7CkXR04Pxp1qWBBHqKv8h9xp+IuwVanXL4ltNjC1G4OlzwyCr5cnadwKmNscHuYFZrqt8Lq7gLuSxXczedlYhSdu3J2rA9fLBpwjhbi23LAwUUqOUIJMmQQcKIBml/WrD3dcz7FYbQXa20rIHhg7mY+bcBgkmaw/2DLol1lsvYKeZnsahhIBO+3cWNy/aK7rPP8A9g9au9P1uh/eNK5Vrb21Ic7yRuUgoQPswpcBZjHHrBf9r2tG7bCi2rIltrRtxDWlCgzHqu7tk/Ss3f0ZFsXrh98+VBAnnkkegP8ARpkqIt2a/XajTpcdNKYRe07gJnAMn4H4EwOK8anqdtrY32w/nXeQBvFvcN8HmYEfWsxa0d63YS+yAWnYIHEF1Jkq3qFO1hB528cGvZuMIY9xIIypH3/gfSuSs7Gi7125pVvXP3ZGCEjZuO5VXYMA8k78/DbyauaPVll3MZnEE4O0gz6mdzTj+XM4HxyrWQvhldwlWIiSOdpPMGKl6OgFoGC25gCByewGeTu9PuqM2ky+NNoudD6hba3dtvZU3bjylzHiDjA9B2niMdq0q2VtiDEwSZ7doE8E+vHFfLOmCMzG3sYY2lYgkTgcxmqWuvEzMkmqKlvkm7eiHXa4BCE4WYJ/Mn65P1pd1XoPhJp/41pg6sJMptbdPft5on4cVLfTykQS5GAPzaTgZz+VZ+7cZptkNdZCck+S3EAkTiRESciutdSFvpY21mkezbtM15bpfLAAqbZIICEn3sKf6ya11iCt1kDKJFuMKd07g7A7jtBkZGB8yVOl1zqjs1rxE4LurMqEmB5iCqkkj4mndv2qFyza09y3/CRgY92ZYtlsg5xx+WEePdjxyaok0fUIm4z+7KxEFl9T5RI83p2Pyq/0G89vU+Kly28pDA3LaMsun2WhoicjExJr71Rrequ21s7bdtEiCd5JPmYbuWgxySFntJo9krJt3NQpZv4irbtvDBLm2WJD8DaCBw0bjgZqf4+l2UWRNUMLujZle6VVU3fzqf7QyNuZMlwMD1+NZ/qFthyMDj4mPwiZzT7qNr+IWCiQCcECIeTyf8RGM+oxihr0LWxidxGB8u0/7/Gs8tS0aI247MrrCFYg/wDr+prwjg8/QgCPwprqfZ3UNbF4WybbkgGVk7QWJgmYAVjMdqTgQOePuz3E1pjwZZbY30XTQ1s3GbFvJxlgMnE/DmtA/sxY1SWn0e4XVAe6zk7WYn3QDwZBiIEVldLqrpR2RWKIILQdstjJ4A55p97N9euW7V244C27RVWk5LOTAUdyACT8IrjlkiuB4whL3RY6JomsuLTiLigFvjPee4rdaE4rNHraXIIVG4MkebIHDA4+RkVoOlXAyhhwf6zV8WTr+y8YdCoZukqR6irnsym3TqPRn/Uaqq0y6SkWgP8AEx+9iavLgyZlwX6KKKQgFFFFABRRRQB8rL/tFH/wLv8Amt/qpWorOe3yzobo/wAVv9VKbH5IWStNHM9CsCrl1xBqCysfSvN15qmV2zd8eNIr611EMURwIlHG5WA5DD0NJ0/eNZcvXA1tVtIWFoEWk2yDtQQczBjJMc8Ux6j7uKy2utW4Bt3WZm3G4kMqptPkE/bxJPpiszexvkRTSKz3blxhcujeTmDAhe35/lTG9q7d22ttgyhDIKwYnB+YpUupbd5sxHwiIHPYQKY6TUSQpaFgyAu8ggfykic+hwJ5iCk+SEI6PS9Ksss+M0iBlAMZwPNjn8KvXrqKAiWzsPvLII3dmU/ZwBOPjXvTW7O7ztuMcLsBB3AHkMGwGxuHbNfNTYQmLVsn/ER5p9GXt27mlU2ts68aekXG1V+4tuwzMLKFoYLgBspb42mWUETnHoIqddC/7rbctAeVUcBtuDHrmfNxj4ZrafWXrNu7atsPCbYXDAEbxAULI5JA5MDmt/pHaxpLSbAGcNEEQwJgKSQCBwCR68Zws2m7HxxaRX0qXHUvcJZ3AJJPcDaDP/j8qW6tFVSxOBkzPP8Auf8Amp+mdRkLb2Mt0XDvzMW4IAPx3ESYHqPhd1WkVlZGnaeWXLYyQBhcmOZj0pXl2kOsXa6Mi2qa5uS2QBw9yR5QTwo5JII+UT6VYvdLUaW7bt++VwByYyR8zSzXaO/bZl3SoxPunzTAEySYzn4/Oqw1+pXl2wY2mZEiQfiIz6CQaZuT2mSjGFU0zxoV1r2G0qI/hHLJ4YktvVwZYTIKjiKsN0I29Ntuwj7ickSB6RMzivbay5dUq1+75fstjjmRuj6CT6TXqxp5JKgQSQstuPaABtAiY57n6VyUpNbZ1QjekVelPctyiqXX3lYjbtgciZEY+PHbNXeldXYMiNce0Ax2SoupLrsJYKVJkKDI7rTGzZWPDcWxJJR1QsobaSEIHvSYmOAF4gRFqOkJcm4BCklhkHl57mQORIH2RxNd67WxeimNtcnnlbput5V8lsrLhvNtG4luN0jM4Mmav/uSu7oqpZW0pO13JI2jcWJgz3P/AG0k6bprhuWrdsAyQoWYjIAaQQ0ACZX+UfCqWt1J8Rikbdr2wDtACmEk7sLA7nuOe9TSvkr1VwyDrOpubU2XG2mT5jKj0gR5e4PPA4zSLSWluXEtu/hhjDORuCj1gc071BJS0Ik+h+BIHH9ZrOdVs+HckGJ/P5/dTQd6Fmlyhwuqs27d3Ty5cN5XRtqED3iwYzlQSByCRThbOj1BGns77aMqsSW3HxBKk/EAspgZgGOwrJezlwLqELW/FzGwgtuLSsEDJndH1p+dX+637w8HazKybGUbk7naDhGGIOe1XlJukRjFK6HfQPZF0ZTe1Fu3b3taZQ3mJScqWEAHaOe2fhW30Ni2tpGtnyFygLES+0kAj57SYrmvs/es6jDvct3C25toG1z/AIYYEGckfPtWz6X061bYG34kAk+duWbkhRhe/cnJmjH5cFo9drZpVNN+ne4PmfzpIhp1073B8z+Zq74FzLRcooopTMFFFFABRRRQB8pB7aCdG/8AmT9Raf0i9sv7nc+afqLXY8o6jmbYFVXbmrN84qncpps34lSK2smKSJph4jFVn1HziT+dOdVS/TPFxgYgjvxBH/ismV0mWcU0vsu2rVp0UMkST5iMjBYkzlRwf+6I7V9u6O2LgtqhDgkkCBCFRBaOGxGexGe1MrOn3bZbaBB7e8rAgzHBgSPhSxLTi825juBBd9w3FYkBQRgebvzByBxkjK72Eo9NWhjpOnYwuSGBORCGR6egj1n05MF+ytlTIcFpPlCsQQygBpOcGTtP3xXrXdR2eQSZIG5mO4kAZ9RwfQ5wQaqCwzwGubxPczBgAgHvnM/HmiN8vg5Pp4XIx1Q05uqLT3Gtgq+4wGe5yxPEQI8oGATE4jaHrlgCxbDCbg2NuRm221UkPuIjkDHqx+NYnotq21/aCYUbUAHlBjzFoPPJ79vXHQeo9ItXLe3bB2wrFYKkDy44Iz8+eJqqk02yTSpRf/Rep3Dxltht0+biNrEB4mSDCnkwOxprptrBmZN23BWR3x3+8fX4GoNSgFvYMARHpgzHyx+NQ6N2t24AkAAAem0Y5MkkflUozSZSUG0WdV7P27iEkieRyNrnaAZPbyiREH7zSvUeztx1MbXe22VJ8zouV2zI9B2ECMd5068NxS4NnYYJDYxmPXkZxz61otC6XFJAwfs8gNGRPMZI7Vog4y0Z5xlHbOep0fULKmxJkBWUEEMPRSADH80SZ+UOtP7N6i3BW6tuRJwSJOSrCMnIAI9BjkHZOA3mkiIAzw0x6QZ4rwtge9weScmTkHiDPw/CqfiVifkdGYPSSouC4ULKzEMgIkOsOLik7SCIB/MUt6jpg20owUwYCrtjtBHB+R/8B11vUhFO0gsckAAiO2WByc/UVmG14YxgMAYWAAeDtEwJBjv2M1mytrg14YxfkQWeovprim3bDwDu3Y3EkAkAdwO3HmPpmpZ09q5cbxLoWUeVAJ3FgRthVnDZ4+zgZFS6tASXZh5SSM4HYTGDwZHalOvQlDsgEcGM/LORgetEJ2lZPLjSbr2W9fo3TcVAYLbS5nEq4WdozuKl4JHoT2iqy27i6hL1gqy2sqzqPNuUTKmQOY78Ux1HtZfc5MBrWxtoUblnj3fKOTj1Ne9BYu3hbAQWrdwkLcbCeUdj34p5Xa6SeOt9Rm7OiYXDtjxHYEbQPeL7oAqfrPTb9u7cXUD+IFJmQZJTHBg4PrVrWiyqAB2OoS6VMEeG1vjGJ9DNW9NqPDbTX7rLda74qFD22k2hPzBn6VRWI6u/RJpdEhuNdtJttwiqrZIOwbvhyCfrWp0D4+AxWa0OuuW7P7sQu0PJaPMcQAT6f+Ke9LbyirYzVBPp2jRWDT/p3uD6/nWasPWk6Z/Zj6/nVXwZ/kcF2iiilMgUUUUAFFFFAHykftiP/iXPmn6i08pL7Xf3W581/wBa11cnY8nLbzVSZquavAqiRiifJ6eNdpW1B5pbv23VJEysj8RTC8Zqp1uwVS1cH2TB+RyPxn76hOPUmh56jYw02qLKdpIAGMd9xyQDuJEAHP514XUIu9miTznEiIIBEjvjtmc5pRp7/MGD8vyz8Pxq1bD3kuImz+GniMS4WUBzETnPHz+VZVj3QkslR2aE6Kyl0TctXZtq7FFabcmNijdDOxIGfQHy5Nem649pLunVLey4+8bgGYJyQziACsYheTIOModLpDb0tzVC4rN4qr4QJ3KFlRn0JfExx3ppp7dnUae5qDqEQp5TbYElhE8g+WT5QO/qKo4yT7VozqUWu5jn2Z0QuX1IWNnYxBQYJ37twySIjgjNavr2ta1bkLHhoTHKhsqAwDSFHrWJ9mOtrbvB2SdyxtXzBgxVSRMSRB/4JrRdT69prz3VVmbaqx5SfEZjBULGEUd5wScHkn9K9nXqdvgl0+vW4URS5ITzs6qvnnbhROPe4JHl++fTI5uvbcSgXeh+BIHHqCap9L8O0DtWATJA7kcT68mo36y128LdgC46q8opGFKkZPYjn5isqalK0jS04xpsV+0trcw2CXY7RxLNwBjIM4+eIqj03qF60BcZGUTtW4QdjkbsSDDcnEz6eobWr7u4Y2y7jzpbDYYqQRDI3v8AoBzjNLtTome0ylruyC9sNv8AeBBblob7QJyBu5MBjbHGlslObcqW0azp3tSLg90zJkD3skhSNuBgekZ9Ilje6qCkpcAgjzBSSQROVn0jPqfTB5LpeolNyndJyRPaJJE8kyJPpPrT/R6nxE8z7sjG3nHBEDJJP9TTSySiEcUJcDm5cVi2553S2Wwo4gmZHfH+bvSd7ql2G0eXggR6RweCVj5YFWLupYTJGeRg7gQx+mZ9ZC9s1S8UBm2GRA+cCSBxjHqfyzmSbbZqbSSQahhO6TBU8xAI4nv3z8s1VZR/XPwOfv8Auqd33GJE8D4n4zHp64/AeGTywPT8cTVYKjPkdvR86drvAuLcCqSoIhgDhl2z84P4VHoupBPEt6i21y2QTZEkeEzckRwYNQ6tTgAAliAO/J5+VW009suouB/DMBtglgBjE4mqKTTI9KabPvQem4N7ajC2G3o+Tsuh1Dj1AYj5RSrTWE/d0uXCWuI8bOJ3AEn6GRTPXJcsXbbqD4N21ct7x7rACSrejSswfj6Gsp0zUm48sO/3STH5n8KvCNkZPejWvrTeueIRE9uwAp/04wCPX8qzfT0IG8jnA+PrT7SPxVYno1qkaPTnArT9KP8ADX6/mayWmbFazpH9kv1/M1R8GP5HBfooopTGFFFFABRRRQB8pP7UD/4z/Nf9YpxSv2j/ALu3zX/UK6hoeSOVdTGYpZeNNupDzGk2oNclyetFUiG2m5xUvW7gFlwY821R9WH/AINetIsSe9L+ugsNvrkfMVOXAuZ9pn7ZIwcwaa67qVu4lhUspbe3bdWZcb/TdGTkz8scYpZqNW912dolo3QI91QvA4wBV/T6vSKtjdZJuJcJutuaLton3QPsmO4zNLWzBJ8ES23KFghK2wHZtpISSFVmx7uYBOINTda6sdQ6uEghES5ACqWWQrY5JByTk1HqOsw95bAFu1d3JtloNuTtBBMeUQBjsO9R2XthD5hJiQMTHEgYxXH2o6u5lvT6zZEttnjPMw315U/+qY2dcrXFCw1xiAACMntkkKPqRVLTFjpLltG3o1wb7XdRskXFJEDzAqZ4kfzVZ0nT9M1tmNy6j21VVUhR4l0z4gVvKVHZVMkzz6I8aexlllHQ76e66t1sXb1zTSbit7p3MsAAMOfQjvIgmvCJctWtqrNuyZDqoRirMNxI53Q0EndiBEZFXW6drBU7WTbbVlVxBUsxO4wTJiMg5OJxnUdP1See0lzxLZUedkC72KQRAG5QWJAWREjgyaV1DgZNze2e9RqvEtvctBlEbVJw+0KPMYjvMEYwI9aW6DXXSiLclhbBCrMAK2SMAY8oH15q9auXHt3GBXZbfw+wIYjjbMkD1+vYxU0OmvFLmoYL4KmN0ifTjv2wKk+vev2WXRSt8aFOr60tu1d072kWW3Ky2zux7pRu3AOc5NUdDqykGR5kIYcmZJIK4KnC4IIOCMHy2tdq9xW4ElrbgjGWzt8nqZOPjFfetBrlxbzhSboIbYwlWXHn5AB2yFBOI44D+UbaEfbOosku6wYySCJEkjnv94OO4U96q/vU8kkSY7wDnEz3744NeLtic5BgEk9iBx6kCBHwrzcGxRgSB3MS3aMCeJjJ55g0iSHbfLLVt8/88cfHOYq2oc4C+ZyEUYBJeFUCfWeZ70p07kjOPv8ATAJ/2+FPOi62zbffdTdtWUH2fEBBWQeRz9/rTJboSUu2w6bbt3LurtuWZdOlxicBt1koG9Ry1yPpWt9n9XpU0nmCNczII3EmfL8sVzjp+qdNVdm2bYvLctshXbAuLny9pIB+tSaZthVUIJdtqeaMngn0yQPqaqn0shXVsb9R6nuW/pTb22tRba5bxGy+hJkHvIgGsT0KyWeOxIj/ADAz9wE1quraZ7XhW7t1We1cYriNpupBQ+mQD9ax/TWe3chpVkJJ+Y/5MVaAq8kbBtQGfyztTA9MU40DzFZm0/m/wnIrQ9LftXY8nprxNNpWwK13Rv7Jfmf9RrG6Stl0b+yX5n/Uaq+DF8ngYUUUUpjCiiigAooooA+Uq9pP7u/zX/UKa0l9rGjS3P8At/1CgfGrmvs5dr3kk0ou80w1bVQbmlZ7FEynGKUdUfvORxTW4YWs71O7Sy4JyprYv1FxSSQCCY47NP5GfwpgelMfLdPhMttroFyR4iwGUIQMkiY7SDmq3TOoCzc3G3buyrLtuLvXzKRO2RJE1J1DR34BvSNqLsDZL2yCwZYJ3KoicnbuWYo6dI86Xa2ilqtGBJU7gJ80ESOzQcgcc+tQJYYiRn4cGnP7/wCJbRfDtjwwwLBQGuhmkbj3iSPiI9BVQ6Qnz2zJGSveOJHqP+K4pemDjez7oesXbCXLaEqtwBXX1AMifX5fGm2u6+t2xYtBLaPaJh1Tae2WY8nHb0FKP3rEPbmBg5B4ie81d0uqsKTNvB4nPbjInkGhgqskua244Be5JA28/ZHEzzUmn6zctiEZY9P/AEcVdXq2kjFlBABmN08+sd4+nrFfE1RuAiza2nswEQMZx8ZxUpJPkrHXixda6lcUsQmGMnEAn5/7VP03qt1QyKkKxBIk4IjIzAPxprp+mgea40k9vQnsOw+761Lp9PuRjaAKgE4yVEeYsI3KF7k4mOxFJ1rhIZwa8mQ9I6i6JesgArcjd5VwREyZkR6j7x3l0ukCkKAx2gsCVny4GDyBkfCSeZqRLVpFHhszBpBZlCyREkEtJ3SWAHAIyTUlrQ3Ldh9QkNa73BCuXC+ZQvvd4+EdxmuO3oIuKaZ5u3IDeYLHfJngfec0v1Vg3BbvRusLci5BPkYCdr+ikYV/n3r146uBadBLRsYsV2NIhmIwy7QREd5ptc0v7leVrdy3dAK73AbaVIVgnJ8u5JLD+aIGaIRSVs5km5OkLOvau0bpOnREtjAROJESSxnccTIxx3k0p6brS99XCki2fKvJABnPrTP2q1Ru32uFAviAHAgERA45xAmsjqQ9m5Kkg8gj0p49zYk+1I33tX1dr1xbxKqYVTGO+J/Gp9+mvay0z20tIiu5VYg+Hb3AR8XAPHasFpdcXZlusStwbSf5f5WA+BrSezvsze8Btb4i+EpKlYJL424/l97n4+lU6WuSdr0Vvbbq371+73hhrloeJ2m6h2Mw+YC/dS7XknwbhGbtvJjnYYJ/AfdV/R9I8a/Y0rFkS2DvuEEAK7TM8QBGab/tHs27dzSWbLBrenteEDzmQTJHvYifrTqmgj5IV6K5IUHggZ9CMT91aPQmDWX03urHafxzWk6f2Hw+7n/auw5PSvRrdDmK2XSP7Jfmf9RrFaE4FbTo39kv1/1GqvgyfJWhhRRRSmMKKKKACiiigD5SL2y/udz5p/rWntZ/23MaK580/UWgpi/kX2cpu1WjNT3BUIGa4exLgh1rwKzHULgmmPXOpKnlXLfl86y168WMmuONsxZcyjpcjXp162Vubt/imAkBSmw+/M+YN7sEdtwxTMae64HiHFpSgloYzI2g+kNBE8VlAaedM16wu8jyRg8MqxgH1rkomXqsZaKxpkuP43iC2yMbcEBg8+QP2IGZOJ245FS2FbU6oojWrQuPKKYS3bJUYUQAAAoExJgTmqurvLqbgS0diQSedowBMcn+vSr/AFax5zcBiSGjA5VeBubuPXGeOKk/2dj+ilr32u6Oq7kO0spOSMYIPyqbT6M+H4pQlNwWQVJkiRIGQCB3EYoVQLRYCTz8TJzP0k/StRpepaW5aS1ZsEMABdV4cMMeZQQQsEe8IZYEetInplXF2tCLSPbBAFkFvpg4MyYA9ZJpha1ruPKIx6AAdsximGq0a27qnSm4mPf3ebI88xAjtGZipH0KhSEWWIOB3IGcd8CfpUJTXBojGS/RSewU2O7lhctrcTBBhhkDiSrAiZB4OJqvZUl3LMFRhtaeCog7femOJ+nMkBnp9YngCwbdsXEdv4gI3kAEH4gD14Pb1qDSavw7g3+7lvdBKMB70YJPEZMZgTXXqWifktjA9OHhrv010qoElbdtTgcjxLi3JwANwzGVJiIGt20uW7bAnTXW81seJvQ+GV3qnvAgAgggkEfaBFajqXXdIunBTUpJC7kDEuVOGATJB+Yis9orVvWK7sXUbvJkeIyrKqGbIHLE4EcA8SybQlJoyd8Il7YGLIrxu5O2efjjtifhNb3T9H0tuwlxx4rsIFsALtJUke8J7fXHPJx/tJ042roEyGUEGIMcZ9TjmqiXXCwGYD4H6fdQppDfjbXIdUcG5tUnYmFE4Hcx6Z/Kk/XbBKJc9JU/19KZImatXdJvtEH1pfydMkzrh1RoxKNTyz1h1teGoieTJzHeOAfjSbU2Tbcqe1S2mx9a26krMTuOjX9G1d/91vOuoUbLZBR5kgHIkDLEcA81mLuue483GJjj0Hy9K2Hsd1G1bt3FZQ7XEYXFf3QARsMfaweKx+qs+YnbtkyBEYPFcjVsZtqmN9A8jngg/StF0+6eawmmvFJPpH5040PW9hhhTpUasfyI/wBjpWhuVuuiGbK/X/Ua5L07r9phzBrqXstqBc0yOOCW/ByKo+Bc8oyhp+x1RRRSmMKKKKACiiigD5Wc9vP7jc+afqLWjrM/tBvqmgus5hQUk/8A6pH40D43U0/2csfikXWOqi3KJlj39Kg6h7QM2LS7R6nmkLuSZOSa4bM3yVXTEguNJJOSeahNWHFQRmmMFhFfVOa9Fa+2Elq49I6uRjprzqZXHGB3imGv6s1wKNoWOczuPM8CBPaoEteWvD26y9abNCjSNN7NLZuKyswD7WJ3xtVZAJ8+DzMghlgke7nX+yugt27ZKi273LYZSULSG8jKhIBIJM5AOYwSY5PxXQvZ3pN86QsLgXeu60C9wKnieRiQFIEqZDCdpDSRFDX+HUxhuXZLnw5PAJfYwlWQOQFuLJ9ZGzkz5ounalTdCmW3CAMEcgmZziJkEHyxwTGEPUYwAR8JwO3b4V9PUm7CD6z3+FRlBt3RdT1VnTtalpbZdmG1FLAG0qhWUGJO3yyRGI5rm+s6iXaV+881BqddeuCLly44mYZiRPrnvUYFM0hFZOpLYzMfOfWmvR+rPZwFVh6NPfJ47YpNbq0lv/z8Km5MolfIw6jrbmouG5cILQBAmAo4Akk/HJ71Cykc1as2l2/4pyI7djNfLtqTHrU72VUdEFtKbaS1KN8CP9qrW9PTXplvFwfKknLR1IyntL02RvA45rM2sGDXVNbogyEVzvqmgNtzitPx8v8AVmX5GL2jofQdLYXQ29SltRd3G05Kz5xBkZzOPvNZr2qd7l0XHJJK7cgCAvAgfOtP7JaW7b066d9yG4rXypSWUbYQj5gfhSn2h6czWxdUEbBuO4jcyse3yPatMX3GaS0ZJ7AKtPqB+dVLtoiD/WKbG3KjBrwbRjjFWIWL7F8gyK/QH7ML2/ptlvVrn4XnH+1cIvaInIBH5V3P9lCkdLsg8hrv69yugjZUUUUDBRRRQAUUUUAFYv8Aa3/0q/8A5rX69uiigD88V8NFFAhG9RJzRRXTqJTUmiHmooqWTxZXH5GgVBFROgoorCjYV2GaZaLWOiPaUwtzn17THpOJ+Q9K+UVX0ILGFfbdFFd9Ai9pMkKePSvjDP8AXrRRUpFIk6IKsWEGKKKmyyGun4r0iDeKKKn/AKUGIQVZ6egl/wDLX2ioy4GLiIIrMe0OnWAYzXyinxeSJ5eDTewDeLbNx83CGHiSd21doAGYAjsBS32nulbF6yuEC/MnzHBJnFFFenD0edkOfae+2BOKuHiiitCMzK+oulfdMV3D9lbk9Lsk87rv69yiiugjY0UUUDBRRRQB/9k=)
[Answer]
**Chain mail**
I can give you only option 2 and sort of 3. A chain mail. It consists of rings, which can be jewelry. It can be exchanged for a different one easily, although not quickly. It can make easily physical contact with your skin if you wear nothing else under it. The convenience is highly open to discussion. Although it doesn't restrict movements much, it does make it more difficult. In addition, there is a good reason not to have a chain mail in direct contact with your skin. Not only do you have rapid heat exchange in warm and cold situations, leading to under cooling or over heating rather quickly, but it'll feel like you're being pinched all over the skin it touches.
This isn't a problem with micro chains though. Still I assume these aren't feasible for the time period.
Why do I still propose it if it doesn't meet all your requirements? Because it's over the top powerful and people would use it. It is based in reality where chain mail is effectively used in combat as one of the most protective gears. The plate mail on top was just an after thought. Each ring is strong and a good shape to deflect. Most had multiple layers, so only the bottom layer is of interest as a jewelry holder, but that still means you have a big advantage.
This one guy has 20 rings on each of his fingers and arm and leg bands tight so he/she can still move? Impressive! A 600 ring build for 600 +5 rings = 3000 skill? Here's a chain mail where 10.000 rings are touching my skin. Still working on the leg section. Destruction of the opponent is very imminent.
[Answer]
[](https://i.stack.imgur.com/WAgch.jpg)
**Safety pins**
A safety pin with a gemstone attached satisfies your definition of jewelry. You can easily pin and remove them from your shirt or pants (on the inside, to ensure they touch your skin), or even your hair.
They also have an advantage over rings in that you don't lose them all if someone chops off your hand in combat.
[Answer]
Q: *"If we define jewelry as a combination of a gemstone and a piece of metal that is worn in such a way that it makes physical contact with the body, what form would enchanted jewelry take if it were designed from the ground up to be practical in a combat situation?"*
Combat situation.. charmed.. that would be an
**Amulet**
I set out to put some *authentic* amulet examples/shapes to give you inspiration for a new design. Below examples would be used to cast a spell, or be powerful in other ways. Your definition makes it quite narrow, a gemstone was not an obvious part of amulets, pendants, charmed rings..
Meant as jewelry with a certain meaning, or working. In combat, Romans wore certain amulets giving strength, or power together..
Most amulets are silver or gold, with a coin, or inscription. Roman officers wore the portrait of the emperor as a pendant, or a ring..
[](https://i.stack.imgur.com/T37wA.png)
( reproduction from <http://www.artnet.com/> )
With gemstone, authentic amulets are rare. Amulets were kept/carried, or worn as a pendant, below example has a reference to magic, English, 16th century, but I'm not sure it was meant for spells, or combat..
[](https://i.stack.imgur.com/EjYoc.png)
(authentic museum piece, <https://nl.pinterest.com/pin/75576099971063253/> )
In combat situations, a ring comes in handy. Just stretch out your arm, making a fist and do the magic. No need to grab deep into clothing or under a harness, for an amulet or pendant to use it.
Roman soldiers wore below ring on the battle field. Like the emperor ring, it is found frequently where battles have been fought. It is *not* a friendship ring, the clasped hands represented (military) virtue and discipline, or *Virtus*,
[](https://i.stack.imgur.com/GaYke.png)
(trade)
Here is another example shape, according to the description it is Tibetan, a sign amulet..
[](https://i.stack.imgur.com/h8ycB.png)
(trade)
[Answer]
Let's try to provide an extra hook for the story, how do we prevent people from using such jewelry.
**Earings**
[](https://i.stack.imgur.com/a4Hqd.jpg)
* You have attachment points for many different pieces.
* Generally visible, specific action required to conceal (rather than hand in pocket).
* (Hook point) Ritual removal of ears as punishment.
[Answer]
## Belts (or even just the buckle)
It's not uncommon to see ostentatious belt buckles. While most are designed to avoid skin contact (metal feels cold) it wouldn't take much to give skin contact, if proximity isn't enough. If the belt itself is magical, skin contact might not be as needful, as encircling the wearer is probably enough for the enchantment to take hold.
[Answer]
Assumption you are positing a "typical fantasy setting" based in medieval western norms:
**Armbands and anklets.**
Partly because they can be made of relatively thick metal making them more durable but also because they're in places people don't instantly think about when you say "jewelry".
Armbands were traditional among the Celts and the Norse but they weren't worn in later eras. They tended to be in the form of either a solid metal band with engravings, inlay, and other surface embellishments or be made of metal cable with a gap and jewels at the ends that don't quite meet. They are worn around the upper arm and neither form is easy to remove and they don't fall off if properly sized.
Anklets have been traditional jewelry in many eastern societies. They almost always take the form of a solid metal ring. They can't fall off if sized properly, especially if the person is wearing anything on their feet. Their unique location so far from the centre of focus of most people makes them very hard to notice for most people even during a modern pat down.
[Answer]
## Weapon Hilt
>
> If we define jewelry as a combination of a gemstone and a piece of metal that is worn in such a way that it makes physical contact with the body.
>
>
>
Similar to Trioxidane's answer, I believe the best solution lies in adding gems to the things you already bring to battle, but instead of your armor which should really have some manner of arming coat between you and the jewelry, a hilt can have gems embedded into it and only benefit the user with a better, more textured grip.
A single sword handle can have dozens or even hundreds of gems worked into it making it easily capable of holding just as many enchantments as a whole hand full of rings, but unlike "worn" jewelry, gem encrusted weapon are grasped. This means you could carry multiple such weapons and simply draw which ever one has the combination of enchantments you like.
A wise person knows that a thing is more than the sum of its parts. If you have hundreds of enchantments at your disposal, some will work well together and some won't. By keeping your enchantments as package sets, each weapon you own can be easily selected for the right circumstance without having to shuffle around a ton of different rings or bobbles each time you want to change your loadout. Each sword has been painstakingly planned out to meet a different threat so that in the heat of battle, when circumstances change, you can change your whole loadout to the right combination of powers in a single action.
[](https://i.stack.imgur.com/gfW2e.jpg)
But it does not need to stop at just swords: you could have a gem encrusted wand for all your ranged spells, or a smaller personal item like a knife or a pocket watch for you "every day" enchantments.
[](https://i.stack.imgur.com/JS4dO.png)
[Answer]
**Charm Bracelet**
The clue is in the name!
A bracelet can be made close-fitting enough to prevent it slipping off, and it can potentially be extended with extra charms (which may have additional enchantments to tie into whatever the bracelet itself has) by threading them onto the band.
Bracelets can be worn comfortably underneath a sleeve and will always be at least partially in contact with the wearer's skin.
Unlike some of the options mentioned elsewhere here, the charm-bracelet can have a clasp to allow it to be easily removed as well.
It's also conveniently near the hands if your magic relies on your source of power being close to where you cast from. (As opposed to a necklace/amulet around your neck, which is closer to your body-core and may be better suited as a defensive measure)
[Answer]
I think you are being too pragmatic. For the story the magic property of the jewel matters more than practical considerations. A stone bringing enlightenment to the wearer would fit better on a crown or a diadem keeping the stone on the front, and if it doesn't fall doing the flips it's just another magic property.
You could look at the practical side for a stone like the one the Galadriel gave to Frodo, it would go on a ring or a bracelet to allow the wearer to point the light in a direction when needed. Even though that one would be better on the tip of a staff.
[Answer]
In a similar vein to [this chain mail answer](https://worldbuilding.stackexchange.com/a/216154/18896), but independently developped, I present:
### Chain
Yes, the most overpowered piece of jewelry you could conceivably wear would be a chain, where each link of the chain has its own enchantment. Links are tiny rings. You could wear it around your neck, but that may not satisfy the "physical contact with the body" requirement. So instead, you wrap it around a limb, like a forearm or leg. Tightly enough that it doesn't move, but not so tightly that it cuts off blood circulation.
The main selling point here is you can have an arbitrarily long chain, carrying an arbitrary amount of enchantment. Links could be designed to be removeable in the field, and by in the field I mean at camp, using tools. You can break down a chain into multiple chains. You can include non-magical links for style or function. You can even go more two-dimensional and fashion your chain into chain mail. A chain mail sock or sleeve would already be more rings than you could possibly wear on your fingers, and possibly more magic than you can actually use.
It's very modular is where I'm getting at.
Of course, if you have an attunment mechanic then you don't have to fiddle with the links, you just pick which enchantments to activate, typically after a good rest/meditation.
>
> Low inconvenience to the wearer while worn
>
>
>
You can wrap a chain around a limb which shouldn't restrict your movements. Depending on the material and how much chain you have, weight may or may not become noticeable. How comfortable it is will likely vary on the metal used and how you wear it. Obviously you'll have a problem if you start covering yourself head to toe in chain.
>
> Low risk of falling off in intense situations
>
>
>
If you wrap it well enough, it won't fall off. You can also wrap a bit of cloth over it, or just wear sleeves or pants, so that it will definitely stay in place.
>
> Ease of switching out for other enchanted items as the situation might demand
>
>
>
It's a chain. Replacing a link in a chain is doable, but it's certainly something that demands a bit of foreplanning. In a typical RPG, that would be done during a rest. You can split the chain into smaller chains that carry groups of enchantments that you commonly use together. You can then swap a bit of chain for another easily.
However if you have an attunement mechanic, where the wearer decides to activate an enchantment or not, you don't even need to bother with that.
**Pros:**
* Modularity. Which means:
+ Can be arbitrarily long, thus have an arbitrary number of enchantment.
+ Links can have arbitrary size, limited only by the skill of the jeweler (for how small they can be) and carrying capacity (for how big and how many you can have).
+ Can be split or combined at will.
+ Can be made to fit pretty much any body part.
* Won't hinder movement with the right configuration.
* Easy to conceil, unless you infiltrate a hammam, sauna, swimming pool, or other similar venue.
* Can be removed whole easily.
* Is bound to look pretty sick when wrapped around your forearm or biceps.
* Can be worn under pretty much any sort of cloth or armour.
**Cons:**
* Might require a minute or two to equip, so swapping chain in combat is going to be difficult.
* Requires some preparation to swap the links, so definitely not possible in combat.
* Is probably going to be more expensive than rings.
[Answer]
**Phallic objects!**
0: Full skin contact - guaranteed.
1: Low inconvenience to the wearer while worn
-> Depends on wearer.
2: Low risk of falling off in intense situations
-> Might not be fulfilled in *very* intense situations. Can be amended by the specialized shape.
3: Ease of switching out for other enchanted items as the situation might demand (so nothing surgically implanted completely inside the body, for example)
-> Moderate. Can prepare before action, but rather not during action.
4 (bonus): Fully concealed!
Also, the proposed "jewelry" already exist in modern use.
I just... won't link to it. Or say what it is called.
] |
[Question]
[
Exhibit A: The apex predator of my world, one that can both fly and swim under water.
[](https://i.stack.imgur.com/dEhfx.png)
[](https://i.stack.imgur.com/jGEsa.jpg)
This deadly monster employs 4 limbs - they act as wings in the air, and fins in the water. It hunts for game in the air, in the oceans, and on land. This body of this thing is the size of a bus. This is all very amazing and this thing is ludicrously threatening with spikes all over the place, 6 eyes, and a spiked tail to boot, but I'm having trouble explaining a particular aspect of the creature.
I bring attention to its mouth:
[](https://i.stack.imgur.com/EmesS.png)
The mouth is placed along the bottom of body, away from the head. I've yet to find an example of such a design on any creature on Earth, where the head and the mouth are completely separated.
If you'd like to see an example what kind of land creatures this thing hunts, please see my question on the [Armatae Bestia](https://worldbuilding.stackexchange.com/questions/25761/how-did-the-armatae-bestia-evolve-studded-plates).
**So the question is, what could have caused the mouth of my creature to develop away from the head?**
Notes:
* The creature occasionally uses its head as a weapon, like an ice pick.
* The creature is a carnivore, and does not need to chew its meals.
* The mouth is also used as a grabbing tool (hence the large amount of spikey-teeth). You can assume that the muscles around that area are strong enough to collectively hold up ~1 ton. You can also assume that the teeth around that area can be individually manipulated to a certain extent (eg: the creature can choose to only use inner ring of spikes instead of both rings to grab smaller objects, or that the creature can use only the outer ring while keeping the inner ring flush with the surrounding area in order to pick up larger objects such as logs/rocks).
* The teeth can be used to rip things apart, by "stabbing" into the target, and then spreading the teeth.
* The slit down the center of the mouth area opens up to accept food. The teeth are often used to "shove" food into that abyss.
* This creature is a solo hunter, not a pack creature. It is very territorial, and often fights other members of its species over prey and territory.
[Answer]
Not sure why, but the first thing I thought of when I saw your second image was a starfish. In fact, that may be a viable ancestor for this creature. After all, a starfish's mouth is located underneath and central:
[](https://i.stack.imgur.com/kBLic.jpg)
[Source](http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0CAYQjB1qFQoTCPqhtffX1sgCFQN5Pgod4hUDeA&url=http%3A%2F%2Fpixshark.com%2Fsea-star-oral-surface.htm&bvm=bv.105814755,d.cWw&psig=AFQjCNFfZTT3O05963ERD316Eok5dp-hvw&ust=1445624165610512)
Not all starfish are soft and cuddly. Some, like the crown-of-thorns, are covered in spikes/spines:
[](https://i.stack.imgur.com/IeVSJ.jpg)
[Source](http://www.oceanwideimages.com/categories.asp?cID=74)
Adapting the arms into wings doesn't seem like too far a stretch, as doing so increases its mobility and, thus, its ability to find prey. The development of eyes also seems like a natural advantage: as mobility improves, you want to be able to see where you're going to avoid running into something with bigger teeth or into a wall.
So you have a six-armed starfish that's covered in spikes and evolves four arms into wings, one into a tail, and the last acquires the brain to process the increased data flow (as well as support the eyes).
EDIT:
According to the Wikipedia entry on [starfish](https://en.wikipedia.org/wiki/Starfish):
>
> The starfish does not have the capacity to plan its actions. If one arm detects an attractive odour, it becomes dominant and temporarily over-rides the other arms to initiate movement towards the prey.
>
>
>
Having multiple "brains" can be detrimental. If two arms detect an attractive odor, which way does the creature go? Developing a single, dominant processor (i.e., the brain) is the best solution, so it can process the information from all the arms. Over time, one arm becomes more and more dominant over the others until it acquires the majority of processing power. In that arm develops the brain. Since that becomes the most likely direction for the creature to move in, it also develops the eyes, providing the shortest route from the new optical sensors to the processing unit to reduce the time it takes to see, identify, and respond a stimulus.
[Answer]
Others have already spoken of how it is most natural for the mouth of a mobile creature, particularly a hunter, to be near its head, so I won't spend too much time reiterating those points. Your question is what could cause the mouth to logically move away from the head, given this natural tendency. Here's my humble idea, take from it what you will: the mouth *hasn't* moved away from the head. Instead, the creature has developed a second mouth.
Suppose that at an earlier point in your creature's evolution, it had a fairly standard beak-mouth as part of its head. Suppose that it also had two strong, grasping legs below its belly to catch food, also quite standard. Think pterosaur. Here's a hypothetical evolutionary chain from that point forward:
1. Creature held its prey in its claws for an extended period.
2. Creature gradually developed a belly cavity in which it could tuck prey for a while after catching it, freeing up its claws for other uses.
3. Creature's belly cavity began to secrete a different kind of sweat than normal (does your creature sweat?) to prematurely soften up the prey, similar to saliva.
4. Creature's belly cavity developed increased sensitivity to its contents, granting safeguards similar to those granted by its standard senses of taste and smell.
5. Creature's belly cavity grew so deep that it fused with its stomach. Creature stopped using its mouth to eat.
6. Creature's grasping legs receded into its belly. Claws have rotated to resemble teeth; they can still grasp but have lost their reach. (An x-ray of your creature's belly would show vestigial leg bones around the belly-mouth.)
7. Creature's beak-mouth atrophied from disuse to whatever degree you find aesthetically appropriate. Beak can still be used as a weapon.
I'm sure this answer could use further polishing, and I'm no biologist, but hey, it's an idea.
[Answer]
The mouth leads directly to the stomach. Therefore there is no need for an esophagus. Conceivably your creature (that is the size of a bus) just swallows its prey whole. Without an esophagus there is no danger of something becoming stuck. This would also explain why the muscles are so strong in that area. They need to be strong in order to keep the struggling prey in and to help the stomach crush them till they stop.
[Answer]
Several animals have their mouth in the center of their body, however, most of them are close to their head. Squid are very similar. [](https://i.stack.imgur.com/jEjYf.jpg)
You also have Star fish [](https://i.stack.imgur.com/c6HZS.jpg)
What both have in common are a mouth surrounded by limbs that hold the prey close to the body. It's quite possible they are starting to eat their prey while it is still alive and thus need to be restrained. Though a water environment might also try to steal the food away to staying attached might just be a wise precaution.
[Answer]
Mouths are placed at one extreme end of the body of most earthly creatures for a very simple and practical reason: to give the creature as long digestive tract as possible. Food enters through the mouth, down to the stomach, then intestines and finally out of the excretory canal.
A creature with a simpler digestive system (and carnivores have a far *faar* simpler digestive tract than herbivores) can afford to have a smaller digestive tract and hence have its mouth placed away from the head region. Here are some of the important things I would like to mention about the placement of head and mouth in Earthly organisms.
# Squid, Starfish And The Like
I would really not like to mention these creatures when we are talking about your predator. These creatures indeed have mouths away from their sensory headquarters (heads where most sensory apparatus are located) but you would immediately notice a few things which make them unrelated for this particular scenario:
* All of these are obligatory aquatic creatures. None of these live on land or fly in the air.
* Neither of these creatures is a vertebrate. Essentially, all vertebrates have mouths at one end of their bodies. Even for creatures which have very simple digestive systems (like obligate carnivores and filter-feeding marine creatures), the mouth is located at one end of the body. This is because all vertebrates descend from [pikaia](https://en.wikipedia.org/wiki/Pikaia), [myllokunmingia](https://en.wikipedia.org/wiki/Myllokunmingia), [haikouichthys](https://en.wikipedia.org/wiki/Haikouichthys) and other primitive vertebrates. All of these had mouths on one end of the body (aka head).
# The One Major Obstacle Placing Mouth At Other Regions
Creatures need to *see* and *smell* the food they are eating. Even when the food is served in a plate (known location) and you know it is poison or dirt-free, still it feels very uncomfortable to try and eat that food with closed eyes.
When you are a predator, the need for sight and smell gets all the more important. You don't want to ingest Artimaratia Bestea's osteoderms or the spines of a porcupine. You also don't want to ingest stones or pebbles or sand with your food. Furthermore, if you need to manipulate your food with your hands, you pretty much need to see what you are doing. When you need to tear bites of flesh from your kill, you need to see where you are biting from, to avoid eating undesired parts like intestines and stuff.
# The Prerequisites Of Mouth On Other Places
* The first and foremost is that the mouth needs to be pretty much *close* to the head so that you can still see and smell (even if partly) your food.
* The next requirement is that your creature does not require a long digestive tract and is an obligate carnivore. This condition is already fulfilled in your creature.
* Your creature ***must*** be able to manipulate its food with prehensile limbs. Now this one is pretty serious. I don't think your creature has fingers on its flippers. even if it did, it won't be able to use its flippers as hands and use them effectively for grappling and moving about its food around its mouth.
* The surface where the creature eats, should be dirt/sand free. I think this one is easily provided.
* If you can have vision related organs around mouth, all the better.
* The group of organisms from which this predator has descended should all have the same body plan. Which means that if you have some other predators with resembling body plans, it would make it all the more realistic to your audience. Creatures are judged by their environments, not by comparison to earthly creatures.
* For very large creatures, the part of body where the mouth is placed, should be able to move easily, without having to move the whole body. I think this one would be hard for your creature. It would look very troublesome for such a large creature to continuously move back and forth and sideways just to eat its food. But then again ... it could also be used to make it look all the more horrific. A grunting bus-sized predator, shaking heavily as it eats. That's some nightmarish stuff!
[Answer]
Like others, I also immediately thought of starfish/squid-type creatures as a starting point, however, let's generalize a bit more then.
As mentioned by several, most creatures have sense organs near/in their head. i.e. near their brain - including eyes, ears, nose, tongue and lips. For the mouth this is quite likely because of the need for quick evaluation of food as suitable/toxic. The shorter the signal pathway, the faster the analysis can be made. To be honest, this could be reasoning backwards, and it may be that the nerve clusters for the senses eventually evolved into a brain, especially since humans, for example, can essentially be viewed as highly evolved worms. We are digestive tracts (mouth to butt) that have evolved appendages that allow us to more easily acquire food.
Anyway, starting from these points, we could come up with a few options.
1) Could your creature have a second mini-brain or neural ganglion in its belly devoted to food analysis? This could then bi-pass the need for signals to go completely to the main brain, and might allow the head to evolve 'separately' for more specialized hunting purposes.
2) Perhaps the original ancient ancestor had a different structure from that of life on Earth (the worm) and thus all body types are different on your world. Perhaps an initially branched form. Maybe this was necessary because of the need to ingest, or separate, components of the environment for biochemical use? Again, this would suggest a vaguely common branched form for all creatures on your planet (similar to how, on Earth, all animals are essentially 'linear' with respect to food ingestion and excretion).
3) Perhaps the food it eats is physically or chemically dangerous and the belly-mouth is a specialized compartment to protect the rest of the creature from its harmful dinner.
4) What if this was a case of symbiotic evolution? What if the belly mouth is actually another organism that is acquired when young and forms a symbiotic relationship?
That's about all I can think of for the moment. Hope some might be helpful.
*Aside*: Incidentally, if it both flies and swims, how well does it do either? What are the wings made of? Are they more bat-ish or oily-feathered?
[Answer]
This immediately reminded me of the delightfully weird *[Opabinia regalis](https://en.wikipedia.org/wiki/Opabinia)*, an extinct arthropod from the Middle Cambrian, when evolution hadn't yet settled down into its now-familiar grooves and was still just throwing stuff at the wall to see what would stick. *Opabinia* looked something like a large shrimp with five (!) stalked eyes; its mouth was at the junction between its head and body, and faced *backwards.* It caught its prey by means of a sort of tentacle on the front of its head that looked like a vacuum-cleaner hose with a barbed crab claw on the end, and then transferred it to the mouth.
So, to answer your question directly: *Because the mouth is not the primary means of grasping food.* Observe how apes, and especially humans, have lost the protruding muzzles of most other land vertibrates: when we want to grasp food, we stretch out our arms instead of our necks, so our mouths don't need to reach outwards.
This doesn't quite fit the details of your description, since your guy clearly does grasp powerfully with its mouth, but let's brainstorm a bit. A large mouth is clearly built for large prey, but the lack of reach makes it ineffective against smaller, more agile targets. So what if it's *adapted for dealing with prey of different sizes?* Against big targets, it slams into them mouth-first and rips into them directly; against small targets, it strikes at them with its agile head to stun or kill, then swallows them whole with the mouth. If you're open to a minor redesign, a longer and pointier "nose" could be used to impale small targets for easy transfer to the mouth, *Opabinia*-style.
One more thought: perhaps the mouth didn't evolve away from the head so much as the head evolved away from the mouth. Its ancestor may have been stumpy and bull-necked, or even lacked a distinct head entirely; as it evolved, the upper skull stretched outwards for agility and range of vision, bringing an extended spine with it, while the mouth remained in place, or else slipped downwards to allow it to grow larger and stronger, with muscles anchored directly to the bones of the torso.
[Answer]
## It originally evolved as a bottom feeder
Most modern earth-bound animals place the mouth near the sense organs for ready target acquisition, and the sense organs near the brain for faster processing.
However, we know that in the Pre-Cambrian, many alternative forms existed, most of which are now lost. (Read Stephen J. Gould for more on this. Sadly, Halucinogenia turned out to be a red herring).
Assume this creature followed a different evolutionary pathway, and it's ancestors evolved as bottom feeding grazers. The ancestor needed to be aware of attack from above, but its food could be filtered from the substrate.
Now assume a mass extinction event leaving an evolutionary power vacuum. One would expect the remaining animals to diversify, filling in all the niches, including that of predator. Fast forward a few million years and we have highly specialised creatures yet retaining the original base body plan.
This is similar to the way that birds, humans and whales now share a body plan. Birds and humans would probably do better as hexapods with specialised forelegs, and whales could probably lose the vestigial pelvis.
[Answer]
Perhaps it could be some sort of defensive adaption, as the head is more vital/sensitive than the belly area. For example, if your creature puts its head close enough to take a bite out of a prey, the prey may retaliate and latch on to its neck. Having the mouth on the underside of the body, it would be harder for a prey to wrap around the body (like a snake would wrap around its prey, or something with hands could strangle at the neck), and it's away from sensitive areas like the eyes and nostrils.
For an illustration of what I mean about protecting the neck while feeding, see bellow: [](https://i.stack.imgur.com/Qp3fq.jpg)
(personal favourite for motivation)
[Answer]
Its principal food source is some sort of coevolved electric eel that tends to render predators unconscious by shock to the head (which we'll regard as a good seat for the brain since we'll put most local sensory organs *apart* from taste there). That works via current directly on tissues not via nerves which just saturate. Snapping of this creature's mouth works mostly reflexively, and the head is separate in order not to receive significant currents.
[Answer]
On earth, "mouth in the head" is a very common but not universal property of animals that *have* something that can reasonably be called a "head", and this basic plan evolved following bilateral symmetry. Wikipedia provides [introductory information about the evolution of heads](https://en.wikipedia.org/wiki/Cephalization).
The basic mechanism is that your animal evolves bilateralism and then based on the axis of symmetry it distinguishes one end from the other by concentrating neural and sensory apparatus at one end (cephalization). So it has a head. Now, if it's going to have a long digestive tract, then the digestive tract also is going to run from one end to the other because of the basic bilaterally symmetric plan. So the only question is which end will be the mouth and which will be the anus, and the overwhelming "decision" from earth animals has been to put the mouth at the "head", that is to say at the end with the sensory organs. That's the plan from which we evolved, and AFAIK it's not observed to have been reversed.
You could in principle have a digestive tract running from front (that is, the human sense of "front", the ventral side) to back (dorsal side) instead of end to end, and remain bilaterally symmetric, but AFAIK that's not observed on earth. The animals in which this plan evolved were basically worm-like, so ventral-dorsal is a very short distance and there were probably all sorts of reasons why putting a hole through the animal in that direction wasn't any kind of improvement in evolutionary terms, whereas putting a hole in the long direction was.
The counter-examples to this plan on earth are starfish (and related animals), which probably had an ancestor with a head but have evolved away from bilateral symmetry entirely, and flatworms, with bilateral symmetry but which don't have a digestive tract at all.
Your creature looks quite bilateral to me, and therefore the flatworm approach seems applicable. No digestive tract, use the mouth to take food into a digestive cavity and then the same mouth to expel indigestible remains. Because the digestive tract is such a major piece of evolutionary "engineering", I would expect the animals on this plan to be only very distantly related to any animals that your planet might have, that *do* have a digestive tract.
Alternatively, you could go for a less earth-like plan, and have a digestive tract running from the mouth to an anus elsewhere on the creature: perhaps the dorsal side, perhaps further down the body on the ventral side. The key point will be that this digestive tract evolved somewhat differently from what happened on earth: for whatever reason there was no need to maximise the length of the digestive tract by running it "end to end", and so the tract didn't form all along the axis of symmetry. The difficulty then is to explain why it was advantageous to have a tract at all, if not to switch from a "batch" process of digestion, to a "flow" process that maximises capacity. Perhaps your creature and all its ancestors digest extremely efficiently and so only need a short tract, but not *quite* efficiently enough to only have one meal "in process" at once, and so a short tract is better than a cavity.
[Answer]
## It evolved from a parasite
Looking at the creature's overall body plan, it brings to mind a structure that would be more logical for a parasite than a predator. Perhaps the ancestor of this creature originally evolved to perch on and drink the blood of/gnaw at the flesh of a much bigger animal, where it wouldn't need to move much from its landing/feeding spot but would need to defend its position from other competing parasites (maybe the host animal only had a small number of 'good spots' where the blood vessels are close enough to the skin). Over time, its mouth would move to the bottom so it could constantly feed, while its head would keep watch and be used for fighting. Not needing to move much except for seeking out a new host, its walking limbs atrophied. This would also explain the spikes - a good method of repelling hands that would try to pry it from its spot.
At some point, certain members of the species started preying on smaller animals, perhaps in between feeding on hosts, swooping down and grabbing them with its mouth. Over time, this became its primary food source, while retaining the same overall body plan.
[Answer]
So, I think we've established that there's no particular reason that we need the oesophagus to run the entire length of the creature, the food could either enter the stomach directly or the oesophagus could conceivably be convoluted like the intestine. Either way it's not a constraint.
We're therefore answering the original question — WHY would the mouth move away from the head. There are some good answers here but the obvious one that I can see is to protect the EYES from the prey. Maybe the main prey species evolved a defence mechanism to attack the eyes when grabbed by this creature. This would be a bad day for any creature that needs 6 eyes for it's day-job, so it would have to quickly counter the move with an adaptation of its own.
Sometimes evolution doesn't chose the "logical" answer but the most expedient one. The mouth drifted further from the front of the face, The prey
developed longer reach with it's defence mechanism and the race stopped with the mouth in the belly.
[Answer]
On your image, it appears that the head still has a snout. Why? If it has a head-like appendage without a mouth I might expect something more like eyestalks and a blowhole. What's the purpose of a chin?!
---
An evolutionary mechanism that allows for more variation in body plan is to think more how [Siphonophors](https://en.m.wikipedia.org/wiki/Siphonophora) work rather than us: we have various different organs grow from cells using the same DNA, but [they](https://en.m.wikipedia.org/wiki/Portuguese_man_o%27_war) produce different "parts" as separate individuals that remain stuck together.
>
> Each zooid is an individual module, but their integration with each other is so strong that the colony attains the function of a large organism. Indeed, most of the zooids are so specialized, they lack the ability to survive on their own. This is somewhat analogous to the construction and function of multicellular organisms; because multicellular organisms have organs which, like zooids, are specialized and interdependent, siphonophores may provide clues regarding the evolution of more complex bodies.
>
>
>
They can have strings of mouths, or be configured arbitrarily without the locked-in developmental stages we must go through.
---
Perhaps the mouth doesn't open to the stomach as is implied, but to a *crop*.
Or perhaps it is just a confining "bell" and other zooids lining it will eat the captive item.
---
Oh, and don't forget Robert L. Forward's [*Saturn Rukh*](https://en.wikipedia.org/wiki/Saturn_Rukh) which has *two* heads, neither of which has a mouth. The mouth is a huge intake for filter feeding, leading to paired gullets.
[Answer]
I think separation of distinct concerns could come into play, namely consumption and aspiration.
You haven't gotten much into how this creature breathes but, given its environment, it is likely that it has somewhat of an unconventional air-intake system.
Maybe the mouth is a gill-like device, suitable for breathing both air and water. This would be very difficult to eat through. Additionally, it might be hard to breathe through a throat large enough to hold a city bus. It also eliminates choking danger from consuming other spiny creatures of the same world.
Perhaps your creature just likes to eat and breathe.
[Answer]
The head is not near the mouth in most animals, the *head is near the mouth*. The mouth is where stuff enters the body, and this is in the direction of travel. So this is where you'd naturally put forward sensors and expand nervous tissue to deal with the data. Evolutionarily speaking, in chordates (and also in many but not all invertebrates) encephalisation went hand in hand with water and food intake.
If you need to wrap yourself around your prey in order to subdue it, then it is more useful to have the mouth halfway down the body. Cf. *Platydemus manokwari*.
Pulmonates breathe through a dedicated "lung mouth" found somewhere in the middle of the body.
] |
[Question]
[
I wanted a habitable planet around a binary star system, so I conjured up a system that let me have one.
The problem that I'm facing is that the goldilocks orbital parameters for this planed ended up being 6.5 au from the stars barycenter, with an orbital period of **6.78 years** (the second planet on this diagram):
[](https://i.stack.imgur.com/5Gutz.png)
The problem is that for storytelling-related purposes I'm not entirely comfortable with years being almost seven times longer than on Earth.
While the planet itself doesn't have pronounced season changes so having 3-year long "winter" isn't an issue (Temperatures do not drop below zero pretty much everywhere except the polar regions), the problem comes from the timekeeping and description of things like the age of the protagonists. Describing somebody as "old with grey hairs, managed to live up to respectably ancient 17 years" is gotta be confusing for the readers even if I'll state prior to that that a year is seven times longer (Noth to mention that describing a "5-year-old" character having snu-snu might attract serious problems in the real life, up to criminal charges, because it will be out of context or outrages readers that don't bother to read carefully).
There also might be some undesired psychological side-effects on the whole culture of the species living on such a mellow and slow to change planet that I'd also prefer to avoid if possible.
So since on Earth year counting is tied closely to changing seasons I thought about decoupling the year and the revolution time around the planet. What if seasons on the planet would cycle faster than it orbits around the star? Can this be possible? If the seasons cycle three times faster, then it brings the year's length to about 2 years long, which is much easier to work with.
My initial try at the justification was to make the planet have a much higher rate of axial tilt precession, but I have no idea if it is actually possible or doesn't come with some nasty side-effects like "your planet is no longer capable of supporting life now".
[Answer]
**He was an old man of 90 harvests**
The seasons on this planet are mild, so ancient people wouldn't care much about how often they went around their suns. Instead, they'd care about when to plant crops and when to sow them.
Clearly, no civilization could live off of harvesting crops only every 6 years (starvation was rampant in early human history even when people only had to wait a single year), so presumably they found some crop that has a biological cycle closer to a single Earth year. This cycle became the rhythm that governed their lives, and it naturally made its way into their language (even if the civilization in your story is post-agrarian).
**He was a young man of 18 tenmoons**
Again, since your planet has mild seasons, perhaps it makes more sense to base the calendar off a different cycle. I like the sound of "tenmoon" as a substitute for year. You don't even need to directly explain it - it's clear from context that your planet has a moon that orbits roughly ten times per Earth year. As long as characters aren't doing anything that makes their age in tenmoons seem different than a person's age in years, the reader will instantly get what you're doing.
Though of course if you don't like making up a word like "tenmoon," you could just say they're 180 moons old. With good subtle writing (or a helpful, less-subtle character alluding to how many days a moon is), it'll become clear and the reader will mentally know to divide by 10. Ages that seem too large don't have the same issues you were worried about with ages that seem too small.
**EDIT:** I can't believe I didn't think of this earlier. There's a periodic celestial event that it would be very natural for the people of your planet to use: **the orbit of the binary suns**.
How long does it take the two suns to make a full rotation in the sky? About a year? (they look about 1 AU apart on your chart). This is a good alternative to using moon cycles, especially if it happens to be about a year long, and it's much more fitting for your solar system in particular. The only issue I'm having is that I can't find a good name for a "year" analogue. "Cycles" is a little too vague, given that the planet and stars are all making cycles.
[Answer]
### One star blocks the heat from the other.
If both stars and your planet are all collinear then your planet is getting hit with one stars worth of heat, the other star is occluded by the closer star. When the stars rotate 90 degrees in their orbits, and both stars are visible to the planet, then your planet gets the power of both of them at once.
So by making your binary system spin faster or slower (by adjusting the distance between stars) you can speed up or slow down the apparent seasons.
---
Of course you won't get even length seasons from this, I don't know the exact size of your suns and their exact orbits, and haven't calculated charts, but extrapolating from our sun I think over a 365 day period it's plausible you'll probably get ~15 days of colder temperatures as one sun partially occluded the other. 2 weeks of snowfall in an otherwise temperate zone would be worthy of being the basis of a calendar.
If the suns have different colours you could have 2 winters per year. The yellow winter and the red winter, for example. This allows the suns to be closer together than if you limit yourself to one winter per year.
[Answer]
Why do humans measure time in years? The reason is that the yearly cycle of seasons is very important for our lifestyle. Depending on the time of the year, humans dress differently, work differently, spend their recreational time differently and eat differently. This was even more extreme when we were still an agricultural society.
The seasons on Earth are caused by axial tilt. So when your planet would have barely any tilt, then it would not experience a seasonal cycle synchronized with its orbit. That would give you space to come up with another naturally occurring periodic phenomenon to serve as a unit of timekeeping.
So when you want a similar unit of timekeeping, then you have to find a natural phenomenon which occurs periodically and has a very large effect on the lifestyle of your species.
Some options could be:
* Strong tides. The tides caused by the planet's moon(s) affect the life of the inhabitants so much that they use it as an increment of timekeeping.
* Biological effects. Perhaps there is some species of insects or [perfectly normal beasts](https://aliens.fandom.com/wiki/Perfectly_Normal_Beast) which have a lifecycle which is synchronized throughout their species (like cicadas). The lifecycle of these animals (or plants?) might also affect the life of the inhabitants in a significant way.
* Periodic volcanic activity causing regular [volcanic winters](https://en.wikipedia.org/wiki/Volcanic_winter).
* Periodic weather phenomena like [dust storms on Mars](https://en.wikipedia.org/wiki/Martian_soil#Atmospheric_dust).
* The star itself is highly irregular and causes seasons due to varying light output.
[Answer]
### You could leave the seasons out of it and somewhat decouple the time counting from astronomical events.
Most people I know are pretty comfortable working with units like weeks and hours without them being directly observable in nature. We use units like this because sticking to days, years and lunar months would give us too large or too small numbers to be comfortable.
Six is a good number with some interesting properties, to the point a mathematician might even say it's [perfect](https://en.wikipedia.org/wiki/Perfect_number) (precisely what this means isn't so important, but priests in your world might like this fact to justify the divine order of things). With such long years it makes perfect sense to divide it into sub-units and why not make them six? It would be like when economists often care more about quarters than years. Now, as we translate into English the word the people there use for such a unit, "year" seems like at least a reasonable translation.
You now get 3 years of each season, summer and winter, dividing them naturally into pre-, mid- and post- stages. Telling someone your age, especially if you're not that old, using solar years seems too coarse. Just like Earth parents might talk about their 18 month old baby, a parent in your world might worry about their 14 sixths old daughter who is way too young to be looking at boys the way she does (some as old as 18!).
Solar years could still be important; 3 solar years is not an unreasonable age of being considered an adult, but you can work around that. Make sure to always refer to them as "solar years" or maybe even abbreviated to "solars". Characters telling their age might just use the number, like we often do in English.
This could have some interesting effects, such as solar birthdays becoming much more important.
[Answer]
# Binary star:
Your answer is right there in your star system configuration, you just need to fiddle a bit with the suns.
You currently have two suns, one heavy and bright, the other much smaller?
Change this so that one star is massive, but not very luminous. This one mainly determines your orbits for the system. As stellar mass *usually* is a strong determinant for luminosity, you might need to make it an old black hole or something.
Let the other star be smaller, but brighter. This is your prime light source "sun" for the system. Have this one orbit in the same plane as the planets, with a suitable orbital time of slightly less than 1 year. When it is nearer the planet, the season is summer. When it is on the other side of the system, the planet experiences winter.
[](https://i.stack.imgur.com/qvNG2.png)
*Unfortunately, while this does answer your question, I suspect it defeats its own purpose, as it forces you to redesign your solar system, which specific design is what prompted this question in the first place, sorry.*
[Answer]
# "Hysterical Raisins"
"Historical reasons" are the only reason that people on another planet would measure time using Earth terms.
Already on the ISS, on the moon, and when we eventually get to Mars, we use (or will initially use) UTC, with Julian days and the Gregorian calendar.
But it stretches reader credulity to have your planet be spinning with a period of 24 hours, and your seasonal cycles be 365.25 days long, and so on.
Sure, it COULD happen, but it's just not plausible, and that strains the suspension of disbelief, or far worse, gives the reader a feeling of contempt for the author, either "they didn't even consider the orbital period would be different!" or "they couldn't even handle writing for a different orbit, and had to fudge things!"
So if you can state that they're recent Human immigrants, then use UTC and have fun playing on the way they manage their lives to handle the weird local times, then go for it! Circadian cycles won't change much, so a 34-hour day could mess people right up! :) MAKE it hard for them, and call it out. "Damn, I hate these every-third-day night shifts", type stuff. If they have a local and a UTC day, what do they call each one? If they just say "day", which one do people assume they mean? Do they instead call the local one a "cycle" or what?
---
But if you can't make them use UTC, then arguably the better answer is **Just Don't.**
For me, then, @RossPresser gave the best answer: DO NOT USE EARTH TIME for measuring time on a different planet. It's always a grating point in sci-fi when you see that. "Days" are the only reasonable thing you can steal from Earth time, and in a binary star system, even that becomes a bit vague.
If you're trying to hide that it's not Earth, then either go the "historical reasons" path and don't call out the pain points of making UTC work locally until after the "reveal", or for an alien race, just don't mention years or ages.
* "She just started High School!"
* "He was counting the days until he graduated from college... not long now"
* "I'll be there in a bit"
* "remember that real cold winter when we were kids?" (do you need to explicitly state there was only ONE winter when they were kids?)
* "He was clearly elderly, but despite her heavy makeup the woman on his arm looked barely legal"
* "sure, he thought, his middle-aged spread was becoming a problem, but he still had it where it counted"
* ... and so on.
You pretty much never need to tell someone's precise age. How many real-life people do you know the precise age of, other than close family and classmates who are obviously going to be your age? For me, I can think of exactly *none*.
It only adds a very slight burden to doublecheck our work in one of the last edit passes to search for all date/time reference terms (year, teenager, hour, minute, second, month, twenties, ...) and replace them with sensible alternatives, but it's a very rare story which requires more time-precision than "today"/"tomorrow"/"when I get back from work".
[Answer]
**Seasons aren't purely dependent on (planetary) Orbital Periods**
In your image, it appears you have a binary pair of stars, with one star significantly larger than the other. This implies to me that the larger of the two will be emitting the most energy and thus contributing the most to planetary warmth. If that difference is sufficiently large, we might be able to ignore the effect of the smaller star for any planet that is orbiting the pair (as Enor does) rather than being coorbital with the smaller star (as Hirr appears to be).
**Except:** any planet that orbits the barycenter of two stars will be closer at any given time to one star than the other, and even if we ignore the emissions of the smaller star, its mass will impart a "wobble" to the larger star. **This wobble can be the source of seasonal variation.**
This gives you some potentially interesting cultural effects. If we measure by "seasons" or "harvests", the time between harvests is dependent on the mutual orbit of the two stars, and could be much shorter than 6.7 years. On the other hand, cultures that depend on the stars (e.g. oceanfaring ones) would care more about the long-cycle swing of the constellations across the sky.
[Answer]
# Just don't use years at all
There are plenty of other units to use:
## Count time in months
Precedent: the Bible
It's [thought by some scholars](https://en.wikipedia.org/wiki/Methuselah#Mistranslation) that the insanely long lives of some Biblical characters were actually measured in months -- i.e. Methuselah died not at 969 years but 969 months (about 78.5 years).
Caveat: you'll have to infodump exactly how long a month is (orbital period of the planet's moon).
## Count time in (work) shifts
Precedent: I can't find it right now but I remember a story, taking place on a tidally locked planet. They distinguished between Days (a full rotation / revolution) and years (old style Earth years), with a line something like this:
>
> 48 years to a Day .... 365 days to a Year ... so how long was a day? three shifts!
>
>
>
## Count time in seconds
Precedent: *Heart of the Comet*, David Brin & Gregory Benford
>
> “There’s rules fellow. Capture without harm or blood spilled isn’t vendetta, it’s fair coup. You work for us in Hydro for **ten megaseconds -- that’s about four months, old style** -- with maybe time off for good behavior.”
>
>
>
## Or just use the longer year anyway
Precedent: *Podkayne of Mars*, Robert A. Heinlein
>
> Perhaps you have seen a book titled: Eleven Years Old: The Pre-Adolescent Adjustment Crisis in the Male. I read it, hoping that it would help me to cope with my brother. **Clark is just six, but the "Eleven Years" referred to in that title are Terran years because it was written on Earth.** If you will apply the conversion factor of 1.8808 to attain real years, you will see that my brother is exactly eleven of those undersized Earth years old.
>
>
>
[Answer]
Two different possibilities:
1. Treat it as a translation issue. The natives speak a language that definitely is not English, and you are presenting a translation. The character might be 5 smeerpyear old, but when translated into Engish, he will be 30something.
2. Even on Earth, there were/are some important calendars based on lunar cycles, not solar seasons (Islamic calendar being perhaps the most prominent). Your planet has a moon with an orbital period somewhat similar to our month, and the "year" has 12 months because it is such a nice round number (and/or they count in duodecimal). Or the period is 18 days, and the year has 20 months (because they have 20 fingers+toes, like the Mayans). Or any other combination. WIthout a moon, a "year" might be the epicycle of a prominent gas giant (though orbital stability probably forbids such a close gas giant). Or perhaps the "month" could be based on the length of a menstrual period.
[Answer]
Touching on the same concepts as some others, if the orbital period of the stars themselves is about one year, and they occlude each other you may have a another "clock" to go by. Depending on the relative size and color of the stars, the color of sunlight itself may change significantly about once a year for a few days, as the larger star occludes the smaller star. ("The red/blue days") If it was noticeable, this would be a pretty celestially significant event, and would probably have a lot of cultural impact.
If the civilization on this planet "grew up" here, this kind of regular event would probably feature heavily in their history, like leaders scheduling great battles on the "red days" for luck, and there would almost certainly be worked into their calendars. (Our own ancient civilizations made a pretty big deal out of eclipses and regular comets.)
[Answer]
This would be a commment but it is too long for that.
Is it even possible for a habitable planet to have a year 6.78 times as long as an Earth year?
At twice the distance from a light source the light will be one quarter as bright. If the two stars are equal in luminosity, the combined light from both of them will equal the light level from one of them when a planet is 1.4142 times as far away as it would be from only one of the stars.
Thus if the two stars have equal luminosity, the inner and outer edges of their combined circumstellar habitable zone will be only 1.4142 times as large as the inner and outer edges of the circumstellar habitable zone around only one of those stars.
In our solar system Mars has a year 1.88 Earth years long and Jupiter has a year 11.86 Earth years long. The asteroid Ceres has a year 4.61 Earth years long.
So a planet orbiting our Sun with a year 6.78 Earth years long would orbit somewhere between the orbits of Ceres and Jupiter. And it would be far too cold to have liquid water on its surface with an atmosphere breathable for beings similar to humans. If it had a more exotic type of atmosphere with a lot more greenhouse gases, it might be warm enough for Earth type lifeforms, but then the atmosphere would almost certainly be unbreathable for large multicelled land animals such as the natives are probably supposed to be.
If each of the two stars in your system are much more luminous than the Sun, a planet at that distance could be warm enough for Earth type life. But each of the two stars should be more massive than than the sun of they are more luminous, so their combined gravitational force on the planet should be much stronger than that of the Sun on a planet at that distance. Thus the planet would have a faster orbital speed and it would take it much less than 6.78 Earth years to complet one orbit.
And a writer can keep adjusting the masses and luminosities of the two stars until he finds a realistic, naturally occuring mass/luminosity that produces an orbital period of 6.78 Earth years somewhere in the systems combined circumstellar habitable zone.
Known exoplanets have orbital periods ranging from a few hours to hundreds of thousands of years. Since the habitable zones of stars are much narrower than the range between the closest and farthest possible planetary orbits, the range in oribital periods of planets in the habitable zones of stars is much smaller, but could still include orbital periods of tens or maybe hundreds of years.
Except that stars luminous enough to have their habitable zones wide enough to include orbits that wide and long probably cannot shine with a steady luminosity long enough for their planets to become habitable for beings similar to humans.
The best scientific discussion of the requirements for planets habitable for human beings, and thus for aliens with similar environmental requirements, is *Habitable Planets for Man*, Stephen H. Dole, 1964, 2007.
[https://www.rand.org/content/dam/rand/pubs/commercial\_books/2007/RAND\_CB179-1.pdf[1]](https://www.rand.org/content/dam/rand/pubs/commercial_books/2007/RAND_CB179-1.pdf%5B1%5D)
Dole explains that it took billions of years for Earth to acquire an oxygen rich atmosphere and become habitable for beings who breath oxygen. Dole also explains that the most massive and luminous stars remain on the main sequence and shine with reasonably steady luminosity for periods shorter than the billions of years necessary for a planet orbiting them to become habitable.
According to Dole's calculations, it should be impossible for a star more massive and luminous than an spectral class F2 star to have a habitable planet. It would also have to be luminosity class V instead of a more luminous, giant type of star.
[https://www.centauri-dreams.org/2014/03/27/habitability-the-case-for-f-class-stars/[2]](https://www.centauri-dreams.org/2014/03/27/habitability-the-case-for-f-class-stars/%5B2%5D)
So you need to find the mass and luminosity of spectral type F2V stars and calculate the inner and outer edges of their habital zones. Then mulitply by 1.4142 since your system is a binary. Then calculate the orbital periods of planets orbiting at the inner and outer edges of the combined circumstellar habitable zones from the distances and from the combined masses of the stars. If a planet oriting at the outer edge of the combined circumstellar habitable zone of a double F2V system would have an orbital period of less than 6.78 Earth years, then it would be almost totally impossible for any habitable planet anywhere to have a year as long as 6.78 Earth years.
One way out that would be to make the two stars more luminous than F2V stars, pushing their combined habitable zone out far enough for a plent in it to have a year 6.78 Earth years long. That would make the stars too short lived for the planet to become habitable naturally, so it would have to have been terraformed and given an oxygen rich atmosphere by an advanced civilization sometime in its plast.
Another way out would be to make the system a double double system. It would have four F2V stars in two pairs. Each pair might obit each other at a distance of about 2 million miles, nearly touching, and the two pairs would orbit each other at about five times that distance, or ten million miles. In such a system the inner and outer edges of the combined circumstellar habitable zone would be twice as wide as the zone around a single F2V star.
Another way out would be be to go to the PlanetPlanet blog and The Ultimate Solar system section, devoted to designing solar systems with the highest possible number of habitable planets.
[https://planetplanet.net/the-ultimate-solar-system/[3]](https://planetplanet.net/the-ultimate-solar-system/%5B3%5D)
Some of those solar systems are so statistically improbable to occur naturally that they would have to have been constructed by advanced civilizations.
And some of the most far out examples there may have set ups where habitable planets could have years as long as 6.78 Earth years or longer.
Added 12-17-2020
One way to have a habitable planet with a year 6.78 Earth years long is to have it orbit outside the circumstellar habitable of its star so that it would be too cold for life except that it has a major source of heat additional to the heat from the star.
One way to do that would be to use tidal heading from tidal ineteractions with other objects in its solar system.
Such an process is discussed in my answer dated 12-17-2020 to this question:
[https://worldbuilding.stackexchange.com/questions/192131/what-are-the-upper-and-lower-year-lengths-for-a-habitable-planet-of-40-eridani-a/192221#192221[4]](https://worldbuilding.stackexchange.com/questions/192131/what-are-the-upper-and-lower-year-lengths-for-a-habitable-planet-of-40-eridani-a/192221#192221%5B4%5D)
[Answer]
Add more planetary " axis wobbles" to the orbit, that way seasons can be entirely independent of year length
[Answer]
Presumably the inhabitants are aliens, not Terrans? If so, **they just live 6.78 times slower,** so that one of their years feels, subjectively, just about as long as one of our years does to us.
Think of it like "cat years," but in reverse.
(If they ARE Terrans, somehow, then you're missing an opportunity if the lengthened year isn't a plot point.)
[Answer]
Your planet has a **very strong** [axial precession](https://en.wikipedia.org/wiki/Axial_precession), with a period of about one Earth's year. This would cause seasons very easily since the main "source" of seasons here on Earth is the fact that one hemisphere is receiving sunlight in a much more direct manner than the other.
I have no clue whether or not such fast precession can ever occur on a rocky planet, but I assume you can safely handwave that part.
[Answer]
They do not divide their time into years, but into seasons. Even on Earth, "four" is not set in stone, cultures have more or less. Then they count their ages in seasons because it gives them a more useful measure of time.
(Perhaps they have different crops for each season because they can't prevent spoilage over the course of the year so that one crop a year works.)
[Answer]
## Who says your orbit must be 6.78 years?
I am by no means an expert in celestial mechanics, but it seems to me that orbiting a dual star means some wonky cool gravity effects are in play. Who's to say that they don't slingshot your planet along with a faster orbit? Some Earth-dude's simulator?
Please keep in mind that humanity is just scratching the surface of what mysteries the universe holds — which means the mathematical models we use are already obsolete. Consider [this Earth-sized planet that the astronomy class I took in college said couldn't exist](https://www.space.com/22451-fastest-earth-size-lava-planet-kepler78b.html). The "old model" said its size should have pushed it away from the star and slowed its orbit.
*Except that we found one that didn't... Cool!*
Sometimes we get too hung up on the idea that what we humans understand today is "The Truth." It's not. It's just a snapshot. It's a little bit better than what we understood yesterday and a little bit worse than what we'll understand tomorrow.
**Alternatively...**
They're your stars, and your planet is orbiting around two of them over the course of one, shall we say, *celestial year.* But during that time you have two summers, one for each star you swing around. "Winter" is when your planet is mid-way (from an energy output perspective) between the two stars. And this is assuming your planet's orbit is a convenient circle. In this instance you have two *seasonal years* because there are two summers and two winters inside of one *celestial year.*
OK, now we're down to 3.39 years. Now let's use your axial tilt and assume those two stars are bookin' around each other (this is a lot less fun if their interdependent orbits are really slow). If this is the case, then in a single *celestial year* your planet will present a tilt-toward both stars and a tilt-away from both stars when closest to each star. (Think of it like this, the planet takes 6.78 years to circle its orbit once. During that time the stars have rotated through their orbits twice.) This halves the length of the *seasonal year* again. Now we're down to what I hope is a palatable 1.695 Earth years per *seasonal year.*
*However, given that you've tagged this [science-fiction](/questions/tagged/science-fiction "show questions tagged 'science-fiction'") and not [science-based](/questions/tagged/science-based "show questions tagged 'science-based'"), I think it's more than enough to just push the planet around faster. You haven't explained why you're creating this star system. Let's assume you're writing a story. 99.999% of your readers won't know if what you're describing is "correct" or not, which is compounded by humanity re-evaluating what "correct" is with each new astronomical discovery. The 0.001% that would know won't care if you write a good story. If they did, they'd never read anything Tolkien wrote.*
[Answer]
**Smaller Stars**
The first thing that comes to mind is to simply reduce the combined mass of your stars in order to move the goldilocks zone closer, and subsequently reduce the orbital period of your planet. I haven't done any math here, but I imagine you could shoot for a combined total of 1 solar mass, allowing for 2 stars on the upper end of the red dwarf range (which caps out around .6 solar masses) or perhaps a mid range orange dwarf (~.7-.8 sm) and a small to medium red dwarf (~.2-.3 sm).
**No Seasons**
A planet with a 0 degree tilt will not experience any seasons at all. You would still have different climate bands at which to grow different crops and establish various cultures, each adapted to their region. Admittedly, this has some serious drawbacks, especially if you are going for harder sci-fi. Seasons play an important role in limiting the spread of pathogens and even allowing certain crops to grow (potatoes, wheat and corn, for example, can only grow in areas where winters are particularly cold, but summers are somewhat warm). *[Here is an interesting article going into more depth on this](https://www.livescience.com/18972-earth-seasons-tilt.html)*
**Mild Seasons and Migratory Cultures**
Giving your planet a slight tilt could allow for enough temperature variation to mitigate the issues mentioned above, among others. Due to the extreme length of each season (3 years of winter, 3 years of summer), cultures would have ample time to migrate between climate zones as things shift.
As temperatures cool they move closer to the equator, spending 6-12 Earth months at each stop, allowing for plenty of time to get in multiple harvests of the crops that thrive there, and build back up strength and supplies for the next leg of the journey. As temperatures rise, they move further away from the equator, eventually reaching their "summer home" where the ground, after a long, cold winter, is once again ready for a new crop of potatoes and the like. Since they would have so much time at each stop, they could easily establish permanent settlements at each one. Reusing these settlements year after year would make them truly migratory, as opposed to nomadic. (Also, people in the Northern and Southern hemispheres would have opposite migration cycles, which could create an interesting dynamic.)
Of course, these migration patterns would only apply to older cultures. Once systems for trade, transportation and communication are established (as well as reliable artificial heating and cooling sources), societies could remain in their settlements all year, producing crops for part of the year and other goods (textiles, tools, etc.) in the off season, importing and exporting as needed.
[Answer]
Base your time system off of the relative motion of *two* objects instead of just one.
Your target planet in question is the second planet in the solar system. What's the orbital period of that first planet? You could define the end of a "year" as the point in time when the inner planet transits the sun.
If you're building the system from scratch, you could fine-tune the planet's moon. Use the phases of the moon to define the months (like we do), and then define the end of a "year" as the point in time when a solar eclipse occurs over a pre-defined location on the planet. You could rig the moon's orbital period to give you whatever time interval you want. Similarly, if your moon is not tidally-locked like ours is, one revolution of the moon could be a year (or season).
You can use the same principle with any number of easily observable astronomical objects to build your space-clock with whatever intervals you desire. You can add things like comets, distant constellations, etc to your system without disturbing your star/planet setup, and you should have the freedom to fine-tune their intervals without any real impact on what you already have. Perhaps the appearance of a highly-visible comet marks the end of each decade, and your definition for "year" is derived from that.
[Answer]
Perhaps you could consider a more radical modification to your star system, to make an easier solution to your question.
There are thought to be two ways in which a planet could orbit in a binary system in a stable manner:
1. A close binary, with distant planets orbiting the stellar barycentre. As others have suggested, you would probably have to look to other ways of marking time - moons, seasons, eclipses, or some other regularly occurring astronomical event.
2. A widely separated binary, with the planets orbiting just one of the stars. To see how this might turn out in a fictional setting, I suggest you take a look at [Brian Aldiss' Helliconia trilogy](https://en.wikipedia.org/wiki/Helliconia), in which the planet orbits the secondary star in a much more life-friendly year of 480 days. The much brighter primary really messes with the civilization every 2000 years or so.
[Answer]
Seasons shorter than your solar year could be caused by a significantly lengthened solar day. It is not unheard of to have a very long solar day - Mercury, for example, has a solar day of about 176 Earth days. Making the day on your planet roughly 365-ish earth days long would give you the same basic four seasons we have. It would also give you some interesting talking points since Sunrise = Spring, Mid-Day = Summer, Sunset = Fall, Mid-Night = Winter. You could name your seasons such.
Intuitively one would think that the summers would be much hotter and winters much colder than what we observe on Earth, and they would tend to be at least somewhat, but not catastrophically so. For example, remember the North and South poles on Earth both go through months of "night" here and they are both livable. The atmosphere would carry enough heat to the night side of the planet to keep it from getting too cold. This could be further mitigated by placing the planet on the outer edge of the goldilocks zone to reduce solar radiation and offsetting that with increased greenhouse gasses relative to the Earth. Reduced solar radiation overall and increased greenhouse gasses would tend to mitigate the temperature differential between the day and night. Anything that served to increase the atmospheric density (whether or not greenhouse gasses are involved) would also tend to increase the efficiency that heat is carried from the day to night side.
Some thought into the positioning of land masses could be used to cause a planet with ocean currents that quite efficiently carried heat as well.
A combination of these factors could conceivably make a world with a day the length of an Earth year have little more variation in "day" and "night" temperatures than we currently see between summer and winter today on Earth.
] |
[Question]
[
The title says it all. If it wasn't maintained for hundreds of years, would the Channel Tunnel collapse?
[Answer]
Thanks to [SeanC](https://worldbuilding.stackexchange.com/users/23111/seanc)'s research, we can read that [the "permanent fixings" should have a lifetime of ~120 years](https://www.icevirtuallibrary.com/doi/abs/10.1680/icien.1992.21685). I'm uncertain as to what sort of error bars are on that figure, or whether there's a good safety margin, but it is a good start.
Once the lining starts breaking down, the tunnel will become unsafe. Most of the tunnel is bored through [marl](https://en.wikipedia.org/wiki/Marl), a relatively soft chalky rock, which doesn't bode well for its very long term survival. Long-lasting chalk excavations [do exist](https://en.wikipedia.org/wiki/Chislehurst_Caves), but the examples all seem to be relatively shallow implying there's not a lot of [overburden](https://en.wikipedia.org/wiki/Overburden_pressure) compared to the Channel Tunnel, which is obviously underneath the sea as well as [a load of rock and crud](https://en.wikipedia.org/wiki/Channel_Tunnel#Geology). The tunnel was designed to cope with a certain amount of cracking and water ingress, but there will obviously be limits, especially over a large timescale.
So I'd guess that a century is probably fine, but a millenium is too long. I'm sure you could handwave something inbetween. One thing to consider is that collapses may only be partial (remember there are 3 bores in total, with links between them) and the rock isn't super strong so some re-excavation may be possible, given suitable equipment and knowhow. Certainly, I wouldn't expect the whole thing to just fold flat suddenly one day.
For the now deleted subquestion: the tunnel is about 50km or 31 miles long. How long it would take you to walk would depend on your fitness, and the condition of the floor after whatever time has elapsed. A day isn't a bad ballpark figure, but I recommend trying a walk of that distance for yourself, just to see!
---
[Zeiss Ikon's answer](https://worldbuilding.stackexchange.com/a/166724/62341) is of course absolutely correct . Apparently, the pumping systems for the tunnel were built to expect [20 litres per second per kilometre](http://batisseurs-tunnel.com/wp-content/uploads/2015/03/1-Le-Projet-Tunnel-sous-La-Manche_C1.pdf) of seepage. The total volume of the three bores is about 5.5 million cubic metres. So it'll take a couple of months to flood. Once submersed, I suspect the 120 year guarantee might be voided.
I do note though that the maximum depth of 40m is pretty tame by mining standards, and you would not need a powerful and modern pumping system to drain it. Primitive steam should be quite enough, if you wanted to do such a thing. Additionally though, the same source that provided the 120 year lifetime figure also says that "internal caulking" should have a *20* year lifetime, and be accessible, presumably for ongoing maintenance and replacement, suggesting that pumping alone is not enough and the tunnel would need active maintenance.
I *suspect* that a flooded tunnel would be restoreable, especially by anyone with a laissez-faire attitude to health and safety. Though the lining would likely saturate, the metal reinforcements require oxygen to break down and that's going to be in short supply after a while. It might not be very safe once drained, but active shoring and re-excavation as the water levels drop seems achievable. It seems unlikely to be doable by a low-tech pre-industrial society, however.
[Answer]
Collapse of the tunnel isn't what would make it impassible first.
The tunnel itself might well last a century or so, but if there's no electric power for as little as a few weeks the tunnel will be closed by water seepage that can't be pumped out.
This water entry happens in all tunnels that go deep enough under the local ground surface – mountain tunnels in Switzerland, for instance, despite being a thousand, or even near two thousand meters elevation, are sloped so the water that comes in will run out on its own. This is obviously not helpful with an underwater tunnel; the center of the tunnel, more or less, *must be* the lowest point. Underwater tunnels, then, must solve the seepage issue with pumps – and if the pumps fail (due to lack of power to run them), there's nothing else that can do their job.
I don't have exact figures for the seepage rate in the Chunnel, but you ought to be able to look up its pumping capacity (thanks to @MorrisTheCat, [this article](http://processengineering.co.uk/article/1298669/eurotunnel-monitors-water-40m-under-the-seabed) quotes 1000 m³/hr), which should be designed with a safety factor of at least three (or a redundancy level at least as good – three pumps, for instance, of which any single one can do the whole job). From that knowledge, you can make a good estimate of how long it would take the tunnel to flood after the last pump quits. Beyond that, it doesn't matter much how long the structure and liner last, the tunnel would have to be pumped out from the ends and/or ventilators just to begin to restore its own ventilation and pumping systems.
Others have suggested that windmills (*a la* Dutch land reclamation with medieval technology) could either keep the tunnel pumped out, or pump it out after it has been flooded for some prolonged period. Given the above figure of roundly a million liters per hour seepage, even when the tunnel is open and under constant maintenance, and the figures I've been gifted for the amount of water removed from the Beemster when the Dutch were pumping it down (comes to around a billion liters a year for a single windmill), plus the approximately 50x greater head required to pump water out of the lowest part of the tunnel, it would take around 450 windmills (equipped with many kilometers of lossless power transfer hardware, since the actual pumps would have to go *down in the tunnel*) just to keep up with the seepage the current pumping system is designed to handle. A hundred or so extra could then pump out the tunnel in a matter of some years.
Unless, of course, there's been even a single, small, partial collapse anywhere below water; such a failure would allow effecively (relative to the ability of pre-industrial equipment to deal with it) unlimited water to flow in as water is removed, rendering the tunnel permanently closed.
[Answer]
For a differing point of view, Alan Weisman wrote a book called [*The World Without Us*](https://rads.stackoverflow.com/amzn/click/com/0312427905), speculating on what would happen to our built legacy if humans suddenly disappeared from the Earth. He noted, for example (before hurricane Sandy) that some subway systems, like those in New York, would flood within days without active human intervention (i.e. continuous pumping). He also dealt specifically with the Channel Tunnel, in the very long-term question of whether Britain could be colonised via that route by new terrestrial animals from Europe, in the context of accounting for ongoing sea-level rise.
His contention was that portions of it would likely flood, making it a block to animal passage (both terrestrial animals and fish, although I guess amphibians could make it), but that the structure itself would likely survive for a very long time:
>
> Should some impetuous animal attempt the journey via Chunnel— the
> English Channel Tunnel, Le Tunnel sous la Manche—after human traffic
> ceases, it might actually make it. Even without maintenance, the
> Chunnel wouldn’t quickly flood like many of the world’s subways,
> because it was dug within a single geologic layer, a bed of chalk marl
> with minimal filtration.
>
>
> Whether an animal would actually try is another matter. All three
> Chunnel tubes—one each for westbound and eastbound trains, and a
> parallel central corridor to service them—are swaddled in concrete.
> For 35 miles there would be no food or water—just pitch darkness.
> Still, it’s not impossible that some continental species might
> recolonize Britain that way: The capacity of organisms to ensconce
> themselves in the world’s most inhospitable places—from lichens on
> Antarctic glaciers to sea worms in 176°F sea vents—may symbolize the
> meaning of life itself. Surely, as small, curious creatures like voles
> or the inevitable Norway rats slither down the Chunnel, some brash
> young wolf will follow their scent.
>
>
> The Chunnel is a true wonder of our times, and, at a cost of \$21
> billion, also the most expensive construction project ever conceived
> until China began damming several rivers at once. Protected by its
> buried bed of marl, it has one of the best chances of any human
> artifact to last millions of years, until continental drift finally
> pulls it apart or scrunches it like an accordion. While still intact,
> however, it may not remain functional. Its two terminals are just a
> few miles from their respective coasts. There’s little chance that the
> Folkestone, England, entrance, nearly 200 feet above current sea
> level, could be breached: the chalk cliffs that separate it from the
> English Channel would have to erode significantly. Far more likely is
> that ascending waters could enter the Coquelles, France, terminal,
> only about 16 feet above sea level on the Calais plain. If so, the
> Chunnel would not completely flood: the marl stratum it follows makes
> a mid-channel dip and then rises, so water would seek the lowest
> levels, leaving part of the chambers clear. Clear, but useless, even
> to daring migrating creatures. But when $21 billion was spent to
> create one of engineering’s greatest wonders, no one imagined that the
> oceans might rise up against us.
>
>
>
[Answer]
## Condensation, alone, will block the tunnel at the bottom
Nevermind leakage. So long as the tunnel is open at both ends, wind will blow through. It will carry air that is warmer than the tunnel walls. Cold air can't hold as much water, so the water will condense out on the cold surfaces of the tunnel.
The continuous action of condensation will cause water to accumulate and run to the bottom of the tunnel. It won't be pumped out befause the tunnel has fallen to disrepair.
Keep in mind - the tunnel is a "V". It quickly descends to depth on each end, however, *there is still a slight grade down to a "bottom point"* - and that's done for drainage reasons - so water accumulates in one place, *so they know where to put the pumps*. Well, the French aren't so good at that, clearly.
[](https://i.stack.imgur.com/W7OG1.png)
[src](https://commons.m.wikimedia.org/wiki/File:Channel_Tunnel_geological_profile_1.svg)
Figure this will take a couple months til full blockage *just from condensation*, if seepage doesn't do it first.
Once it fills the bottom of a "vee", the wind will stop blowing and the condensation rate will slow greatly.
] |
[Question]
[
Colonists have set up a viable, long term lunar colony on the near-side of the moon in the mid-21st century. They are quickly reaching total self-sufficiency and the earth governments who sponsored the colony are getting itchy to maintain control.
Earlier control measures such as sending space marines to ensure a toe-hold on the Moon failed. The colonists shot down the troop carrier along with all the drones sent to provide covering fire. They are very good at shooting down anything that comes their way. The colonists are self-sufficient enough that a siege of the moon wouldn't work either.
Neither Earth nor the Moon can yet maneuver sizeable asteroids so bombardment by big rocks is out. Hypervelocity projectiles are insufficiently accurate to do the damage required. Lasers can be defeated by simply throwing lunar dust into the air. Guided nuclear warheads are agreed upon as the best option. Development begins on a W90 warhead.
**How difficult would it be to build a guided nuclear warheads that would escape detection till it's too late?** If a warhead can't be made completely undetectable, at what approximate range would it be detectable? (Too late is less than 15 minutes.)
The warhead should evade visual, thermal and radar detection. The Moon, thus far, only has detection facilities on the Moon itself. The colonists have access to x-band radar and sophisticated machine learning capabilities.
*I'm aware of the maxim "There is no stealth in space." Push the technology as far as you can.*
[Answer]
## Why not?
Make it a relatively dumb bomb on a timer, paint it black, give it [radar absorbent plating](https://en.wikipedia.org/wiki/Radiation-absorbent_material), and (this is the important part) *launch it from the far side of Earth*.
Your delivery system can be whatever you want - mass driver, rockets, whatever - just make sure that all the thermal bloom associated with an atmospheric launch happens on the far side of the planet. No way for the lunar colonists to detect that unless they have satellites in Earth orbit... which would be a pretty major vulnerability. Craft the orbit of the new highly-stealthy piece of space debris so that it will arrive on the moon.
The lunar base, being a *base*, cannot dodge. You'll know where it is in a few weeks. The bomb emits virtually nothing. It's travelling at orbital velocity, and will presumably detonate in the many-megaton range. Counter that, helpless lunar colonists!
[Answer]
This is just to add some more details to [jdunlop's answer](https://worldbuilding.stackexchange.com/a/108454/21222).
I have done something like that quite a few times in Kerbal Space Program. Not because I wanted to bombard the game's equivalent to our Moon, but because I am cheap. Some missions require you to gather data from a certain altitude from the Mün's surface, but don't say anything about soft landing or returning, so a dumb impactor is the cheapest way to go.
If you want to go from a planet to a satellite of that planet, Hohmann is your homie. This is what a Hohmann transfer to the Moon looks like:
[](https://i.stack.imgur.com/28NRi.png)
As you can see, a single burn is required to set you towards the Moon. A second burn is required if you want to orbit the Moon after that, but that would be no fun we don't want that.
### Could we add enough speed in one burn to reach the Moon?
**Yes, we can**! [The russians did so for the first time in 1959, followed by US's Apollo missions](https://en.wikipedia.org/wiki/Trans-lunar_injection#History):
>
> The first space probe to successfully perform TLI [Trans-lunar injection] was the Soviet Union's Luna 1 on January 2, 1959. The first human-crewed mission to successfully perform this procedure, and thus becoming the first humans to leave the Earth's influence, was Apollo 8 on December 21, 1968.
>
>
> For the Apollo lunar missions, the restartable J-2 engine in the third (S-IVB) stage of the Saturn V rocket performed TLI. This particular TLI burn lasted approximately 350 seconds(...)
>
>
>
So, with technology that is largely outdated today, we can accelerate humans from low Earth orbit to a Moon-impacting trajectory in less than six minutes. I have a feeling that by the time we colonize the Moon we should be able to accelerate a bomb towards the Moon in much less time.
### Could we do it without being seen from the Moon?
Sure! [Look at this essay from NASA, about the Apollo missions' launch windows](https://history.nasa.gov/afj/launchwindow/lw1.html) (all emphasis are mine):
>
> In order to accomplish this 'rendezvous' with a minimum expenditure of propellant, the injection (TLI) must occur very close to the extension of the earth-moon line at the time of the spacecrafts lunar arrival. **This is termed the negative of the unit vector of the moons position (the position on the opposite side of the earth from the sub-lunar point), which is called the moons antipode**. The optimum trajectory is **very similar to a Hohmann transfer**.
>
>
> This minimum energy transfer trajectory would have placed the earth parking orbit perigee at the moons antipode if the moons mass did not perturb the trans lunar trajectory. However the moon does perturb the spacecrafts trans lunar trajectory, as shown in figure 5 above, and therefore the **earth parking orbit perigee must lead the moons antipode by approximately 8 degrees to compensate**. The apogee altitude of the osculating conic trans lunar trajectory was determined by the trans lunar flight time which defined the trajectory energy requirements at trans lunar injection (TLI).
>
>
> To inject the spacecraft to the moon in the most efficient manner, an impulsive velocity (acceleration) would be added along the orbital velocity vector (direction), giving an injection at the perigee of the trans lunar conic. Since an impulsive (instant) addition of velocity is not possible, a finite burn time is required, and **the actual injection position is on the order of 20° ahead on the antipode**. The thrust from the S-IVB is directed approximately along the velocity vector, and as the velocity increases above orbital, the altitude and flight-path angle increase. For the Apollo lunar orbit rendezvous flight mode, by the time sufficient energy has been gained, the altitude has increased by 60 to 75 n. miles above that of the earth parking orbit and a positive flight-path angle of 6° had been attained. Since the conic trajectory is very nearly parabolic (eccentricity 0.97) the true anomaly is approximately equal to twice the flight-path angle, so **perigee is approximately 12° to 14° behind the burn cut-off position. The TLI burn arc itself is 25°, so that ignition always occurs within a few degrees of the moons antipode**.
>
>
>
Again, a rocket with current or better technology, and more specifically not carrying squishy humans would easily outperform the *J-2* and *Saturn V* rockets used in the late 60's. All in all, the TLI would look like this...
[](https://i.stack.imgur.com/EpJyr.png)
... But the payload would not need to perform a full orbit around the Earth before the trans-lunar injection burn.
### Can we make the payload stealthy?
Of course we can! First things first, drop the requirement that it has to be a nuke, that is wasteful and inelegant. You don't need a nuke to do some huge damage.
With current or near future technology, it would be quite feasible to send them lunarians:
* A 100 meters wide lump of iron;
* Hitting the ground at 45°;
* And touching ground at 5 kilometers per second.
You may be thinking that a hundred meters is too much. It is for today, but not for a civilization that has built a self-sufficient colony on the moon.
One advantage of iron is that it will cool off in minutes after the TLI burn. If you need it to cool in less time, you can add a heat sink as part of the TLI stage, and you can make that stage turn around and return to Earth a minute after decoupling from the payload.
With no burns visible from the Moon, no radioactive material in it, and zero emissions, they would not see it until it is too close. As for how much damage that would do, I have used a simulator to drive my point:
<http://simulator.down2earth.eu/results.html?lang=en&dist=&planet=Moon&dist=0&diam=100&traj=45&velo=5&pjd=4&tjd=i&wlvl=0>
Here is what the impact profile would look like. The Empire State building would fit inside the crater:
[](https://i.stack.imgur.com/puRjj.png)
I think the debris flying out of that would cause multiple smaller cratters to appear surrounding the main one. And since this is cheap and simple, you can just rinse and repeat. Have fun!
### Could they really not see it coming?
We can barely predict where a falling space station will touch down, and it is not unusual for us to learn about a passing asteroid after it has passed by us.
### Supposing they do see it coming, what can they do?
Lunarians' only hope is deflection. If you blow the payload up, the pieces will still have momentum going towards the moon, and the damage will be practically the same - only more spread throughout the land. Add to that, the Earth can simply keep spamming those things at them. At some point surrendering becomes cheaper than maintaining a permeable defense system just to fight an uphill battle.
[Answer]
Since the effect the EarthForce seems to want is total destruction, there are actually a multitude of ways to achieve the effect.
Firstly, since there is an effective missile defence screen, direct attacks with large, slow rockets is unlikely to be effective. What you might need is to suppress the defence grid with radiation weapons delivering energy at the speed of light. EMP, high energy microwaves and lasers are all available today, so sending drone weapons to blanket the near side of the Moon with with high energy radiation wherever a weapons or sensor emplacement is known or suspected is an obvious first step.
EMP can be generated with [explosively driven devices](https://infogalactic.com/info/Explosively_pumped_flux_compression_generator), so large numbers of non nuclear rounds can be built and sent to cripple enemy electronic devices. Lasers and high power microwave generators will be larger and more vulnerable, but there is no size limits in principle, and astoundingly large generators and antenna or mirrors can be built in Earth orbit and slowly manoeuvred into firing positions. In principle an X-ray [Free Electron Laser](https://infogalactic.com/info/Free-electron_laser) (FEL) can be built capable of delivering enough energy to vapourize metals, carbon fibre and ceramics in milliseconds at a distance of *one light second* (just slightly less than the distance from the Earth to the Moon), but a Ravening Beam of Death (RBoD) is somewhat beyond current day technology. So expect an active campaign to suppress any defensive systems, and take out surface installations like solar arrays and radiators.
Another weapons system which can bypass the defences of the Moon would be space based mass drivers or railguns. Even small projectiles can pack a massive punch if delivered at a great enough velocity, and small, high speed projectiles would be exceedingly difficult to track and destroy. The delivery systems will be space warships in their own right, the proposed "Have Sting" electromagnetic launcher from the [SDI](https://infogalactic.com/info/Strategic_Defense_Initiative) era was of a similar size (but greater mass) than the present [ISS](https://infogalactic.com/info/International_Space_Station).
[](https://i.stack.imgur.com/67gjU.gif)
*Have Sting compared to the space shuttle. Diagram by [Scott Lowther](http://up-ship.com/blog/)*
So even without stealth, we can engage the Lunar defence grid outside of their range and carve a path for the nuclear package to arrive.
But building and delivering laser and railgun weapons into cis lunar space is going to be expensive and time consuming, and you want something much faster and more compact? Never fear. Nuclear devices can be used to drive effects, being a very compact energy source in their own right. Since there is nothing to transmit the energy in a vacuum (unlike the atmosphere converting the intense x-ray radiation of a nuclear blast into an energetic shockwave), you would essentially have to land a nuclear device on the surface to truly destroy the moonbase. On the other hand, several different ways exist to convert the energy of nuclear explosions into useful effects.
In the Atomic Rockets "[Conventional weapons](http://www.projectrho.com/public_html/rocket/spacegunconvent.php)" section, there are several different variations of nuclear "shaped charges".
>
> Another device being investigated by both SDI architects and weapon designers is "a kind of nuclear shotgun with little pellets" named Prometheus. According to a Congressional report that was otherwise quite pessimistic about SDI, Prometheus "may have nearer-term applications for picking out warheads from decoys" (in the midcourse phase of ballistic-missile flight) than the Neutral Particle Beam (NPB), a leading contender for that role. Encouraged by experiments already conducted, SDI officials in 1987 ordered an acceleration of the Prometheus project for "concept verification," using funds from that year's $500 million supplemental SDI request.
>
>
> One research engineer familiar with the project described the device as operating much like a rifle, using a polystyrene-filled barrel to help couple a plate to the "gunpowder-like" blast of a directed nuclear charge. After the impulse from the explosion generates an intense shock wave, the plate "fractionates" into millions of tiny particles. Of course, these would vaporize if in direct contact with the bomb, but as configured, the pellets have reportedly achieved speeds of **100 kilometers per second** without vaporization.‡
>
>
>
Beyond "Shotguns", there are also nuclear [Explosively Forged Projectiles](https://infogalactic.com/info/Explosively_formed_penetrator) (EFP's), useful for cracking open the underground base, Nuclear "Shaped Charges", similar in principle to a [HEAT](https://infogalactic.com/info/Shaped_charge) round, but projecting the molten metal "jet" at @ .03 *c*, and the [Casaba Howitzer](http://toughsf.blogspot.com/2016/06/the-nuclear-spear-casaba-howitzer.html), which focuses the energy of the nuclear warhead into a star hot spindle moving at @ .1 *c*, delivering laser like energy to the target from a range of hundreds to thousands of kilometres.
[](https://i.stack.imgur.com/aQmdY.jpg)
*Cross section of a "Nuclear Pulse Unit" from an ORION nuclear pulse drive. A CASABA Howitzer would be based on a similar unit*
Once again, these can be delivered to just outside the range of the defence grid and then detonated, destroying any surface mounted sensors and launch or laser arrays, and then cracking open the base itself with a slug or jet moving at a large fraction of the speed of light.
As for obscuring the device, it simply has to be launched on a low energy ballistic trajectory, so its origin isn't made obvious by a rocket burn. The device can be protected in a [conical shroud](https://gizmodo.com/5162837/misty-stealth-satellite-hides-perfectly-while-watching-you) which deflects radar away from it, and kept cooled close to the background temperature of space by filling the shroud with [liquid hydrogen](http://toughsf.blogspot.com/2016/10/the-hydrogen-steamer-stealth-spaceship.html) and allowing it to slowly vent, carrying away waste heat.
[](https://i.stack.imgur.com/e6mVZ.jpg)
*Misty low observable shroud. The pointed end would be facing the Moon as it approached, and liquid hydrogen wold be slowly boiling off to keep it close to the temperature of the space background*
So a deadly attack on the Moonbase would likely be delivered by either a small flotilla of spacecraft supressing the defences with radiation weapons and hypervelocity slugs, or a series of nuclear shaped charges which use the energy of the nuclear device to deliver high speed projectiles and energy to scour the surface and "crack open" the base to kill it. Nuclear weapons, or even scouting spacecraft to observe the target would be concealed within "Misty" shrouds, and cooled with liquid hydrogen to evade sensors until they came very close to the target. Considering shaped charged can be fired from thousands of kilometres away and deliver effects at fractions of light speed, you actually don't even have to get too close.
[Answer]
The Missiles will be launched in Earth's shadow and enter a trajectory that will hit the base (... near enough) without any burns outside that shadow. Probably high up, then entering an excentric elliptic orbit that will hit the Moon on the right spot. The hard part is, of course, stealth.
*Radar* - a radar absorptive coating should be doable with near future tech, or even curent one.
*Occlusion* - warheads are small, no big problem for stars. Course should not cross the Earth from Moon's perspective.
*Heat* - the biggest problem. Each warhead could be cooled pre-launch, then launched together with a powerful heat pump that will cool it further in orbit. The challenge will be to build a nuke that works at really low temperatures, thermal shrinkage and the chemistry of the explosives might pose a problem. How low? Theoretically we want 4K, temeperature of the cosmic microwave background. Realistically, since intensity of thermal radiation scales with the fourth power of temperature, we 'just' need to come below the detection treshold of Moon's IR scanners. The missiles will likely spend a day at least en route, plenty of time to become heated up by the sun. So I am stealing an idea from the short story "A Soldier of the City" (dunno by whom): each missile has a large shield, pointed at the Moon. The front side is cooled to be 'cold enough' to evade detection, and is large enough to hide the large radiators pointig backwards, dumping the excess heat.
From the above, it follows that times of full Moon (when the missiles will fly away from the sun, towards the Moon) is the best attack window, as the cold shield will be out of direct solar radtiation then.
Depending on the sensors the Moon people have, an interesting discussion can be had about course: making out a small target (<10 m) in front of the sun is hard, unless one has a special instrument built for looking at the sun and handling its intense emission. I suspect that any lunar colony will be very interested in solar storms, so I'd guess they have instrumentation that can maybe make out a cold spot in front of the sun. So the missile fleet will use cold space as a backdrop.
Of course, the Moon militia will have read this post (or A Soldier of the City, which is all in all a better read) and will launch micro observation satellites (or buy info from earthbound stargazers) all over the Earth-Luna system ASAP, missiles as described above would be quite visible from the sides and rear.
But terran militaries will anticipate this, and construct warheads with internal heatdumps: the missile starts with a large tank of liquid helium (or another medium with lots of energy intensive phase changes at very low tempreatures), the heat pumps will try to cool the whole surface and dump the heat into the internal tank. These would be perfectly dark from all around, but would require trajectories that reach the target quickly.
One could park a fleet at the [Earth-Moon L3 point](https://en.wikipedia.org/wiki/Lagrangian_point) (from Luna: behind Earth). They would barrel towards Luna on a trajectory that goes close by Earth, gathering speed and using external heat radiators while behind the Earth (for an observer on Luna), and coast once outside of it. Of course this gives a rather small area in space for the Moon militia to point their surveillance sats at.
Last not least, the Moon militia can always burrow deeper into the moon, to hide bunkers, protect civilians and guarantee a second strike capability. So the sanest option (but probably not the one you'll base your story on) will be to find a peaceful modus vivendi between Earth and Moon. In Kim Stanley Robinson's Red/Green/Blue Mars trilogy, they needed 200 years (IIRC) and three fat books to manage, maybe your lunans be quicker.
[Answer]
**Compensate With Tactics, not Tech**
Missile launches have crazy impressive launch signatures which are easily detected from space. The lunar defenders can watch anything that is launched from earth into space and the earth-governments can't really do anything to stop them from doing so. Either earth to lunar launched nukes, or earth orbital to lunar launch signatures are basically impossible to disguise. Whats worse, the lunar defenders literally have days to prepare a response for anything they watch leave earths atmosphere or it's orbit.
So, what the earth government needs to do is use covert ops. Instead of crazy expensive new tech development they modify how they use what they already have. Hyper velocity rail guns are fired at the moon colony, but these projectiles are different, they detonate into clouds of hyper-velocity sand just outside the lunar defense envelope. These high velocity clouds of sand scour sensor lenses, and laser or other weapons emplacements sensor arrays blurring or even outright destroying any ability they have to detect objects. The only way to preserve sensors and weapons targeting lenses is to shutter them, thus also rendering them blind. Only microseconds behind the impact of these hyper velocity dust could bursts there is another wave of hyper-velocity projectiles containing nuclear warheads. Constellations of small limited use drones launched to arrive just outside the defensive envelope at precisely the right moment for the sand-blaster rounds to hit are also in play. These are simple and cheap drones, maybe only with enough power to fire one laser-pulse or a single conventional nuclear missile, or to simply explode in shotgun-like blasts of chaff and flares and further assorted sensor clutter. There are a TON of them. They each have a very specific target. The laser drones target and fire on the shuttered, ablated, or destroyed sensor arrays and defensive weapons emplacements further degrading defensive capability and increasing likelihood of a successful strike by one of the drone launched conventional nuclear missiles. Since we are dealing with swarms of drone craft launching nukes, and waves of hyper-velocity rail-gun fired nuclear warheads only a few, maybe even only one has to successfully penetrate the defensive network for the strike to be a success.
Developing super secret sneaky tech is very expensive and takes decades, this doesn't make it a non-viable option mind you, but if the colonists just torched a troop carrier your earth government will want a way to retaliate **NOW**, not 15 years and 800 billion dollars of research and development later.
Hell, go for a psychological option and have all the "nukes" that make it through the defenses be just regular conventional explosive warheads. Follow them up with a radio broadcast demanding surrender and promising live nuclear warheads are due to arrive soon. This way you have a chance to recapture your crazy expensive colony before nuking it to oblivion.
[Answer]
*Our preeminent and loquacious benefactor, Xanax the First (may His edifactory sardonicism calm us forever!), had declared the lunar colony of the moribund nation of Anathemia to be obstructive of his grand view of the universal glory! It must be erased from existence!*
The problem, of course, is that with a 9 hour transit time our nuclear missles are easily seen and even more easily shot down long before their radiative bloom can cleanse the lunar surface.
Your task, and it is imperative that you take it, is to present to His Ultimate Pacification a plan for delivering the metaphor of his wrath and vengence in a guaranteed manner. *We love you Xanax!*
**photons are not your friend**
* While it's unlikely to detect an object as small as an ICBM from the color of its shell metal, it's not impossible. Therefore, the missle must be painted matte black.
* But that's not enough. As the missle passes in front of stars, they will be occluded. This either requires the missle to be fairly small, or the surface must be designed with an imaging surface that will present the starfield, or something similar, toward the lunar surface.
* The inner shell must be black-body (I believe this is the correct term) absorbing to ensure no radiation from the nuclear mass or the engine is lost for detection.
* The outer shell must also be absorbing to ensure that incoming radiative scans (radar, etc.) don't reflect. However, I think this should be a bit more comprehensive. What happens if the scan expects to detect the international space station ... but doesn't? The absence of something that should be there is as revealing as the presence of something that shouldn't be there. Therefore, the missle might need to be smart enough to know where it is in alignment with detected scan sources and reflect enough signal to ensure a false positive.
* The shape of the missle should balance the need to project false images to protect its approach with the need to minimize its detection signature.
* The missles need to leave the lunar orbital plane, ideally by so great a distance that the Earth is no longer behind the missles should a line be drawn from any point on the moon, through the missle, and beyond. It is much simpler to compensate for the occluded light of distant stars than the occluded light of the Earth itself. If possible, this same argument should be applied to the Sun such that the missles are not in line between the moon and the Sun.
**The heat bloom is a massive problem**
* The launch isn't the biggest problem. Keep up a steady satelite launch program that allows you to mix in your nukes and you're in business. It's hard to track a single tree in a forest. Over the course of time, a few "satelites" go down or are discontinued (powered down) leaving, at best, only a radar signature to track. But how small an object in orbit around Earth can be tracked from the moon? My point is, it shouldn't be a problem to mask the launch.
* But once we're in space, a lovely heat bloom would be trivial to track from the moon. But we had to reach 7 miles-per-second just to escape Earth's gravity. That's ony twice what the missles want in the first place. That means the missle is traveling to the moon in 9 hours rather than 16. This means all we really need is thrusters, and for that we can live with compressed air. No heat bloom for course corrections.
*One might be tempted to believe that with the addition of more fuel, the missle could achieve speeds that would render the need for stealth moot. The reality is that the fuel also increases mass making it more difficult to accelerate the missle. It also increases missle volume making it easier to detect and destroy. While a bit more fuel to reduce the transit time to, say, 6 hours may be preferrable. That would be a practical limit.*
* One last major burst of air as the missle nears its target in an effort to avoid the consequences of any early detection is preferable.
* The engine and liquid fuel tanks should be jettisoned for incineration on the far side of the planet to make the actual missle as small as possible.
**One missle isn't difficult. An hundred is a bit more of a challenge**
* A large group of missles would easily occlude light and increase overall mass to simple radar detection. Therefore, as early as possible and in tandem with the need to leave the lunar orbital plane mentioned earlier, the missles need to be spread apart.
*This report being submitted during the Season of Adjur upon the second day of the Festival of Bequeathment unto the noble brow of the Lord of Mendelin for His consideration and approval as directed by my superiors in favor within the Hall of Adjudiciary Contentment that the will of Xanax the First be bound to eternity. Xanax!*
[Answer]
Arguably the best way to hide such a thing would be to simply disguise it as something else. A nuclear weapon is simply a payload of a rocket - a rocket which might be carrying any number of things, such as supplies or scientific equipment. The ability to detect any spurious radiation from the warhead itself would be too late to stop it. Sure at a certain point they would probably extrapolate its trajectory and figure out that's a problem, but it might be too late. You can go from "huh, the moon is a long way away" to "wow we're impacting it at high velocity" pretty quick: <https://www.youtube.com/watch?v=dE8pe2EYlZA>
[Answer]
We have stealth planes so a stealth missile isn't that far a stretch.
If you don't mind waiting, you'd fire the missile on such a path that it would reach the moon out of view and orbit until close and then blast in at the last second giving them no time to react.
If you consider we miss a lot of asteroids which aren't stealth. A missile painted black and following a trajectory already established so it doesn't have to use its rockets would be very hard to spot. If it used a stealth fighter like design with the radar blocking paint, it would be virtually impossible.
[Answer]
You don't waste time and resources trying to invent something that's supposedly maybe undetectable, because we already have the technology to solve the problem of "enemy can shoot down our missiles": [penetration aids](https://en.wikipedia.org/wiki/Penetration_aid).
In short, you build a lot of rockets with range to get to the moon, equip each with a few small nuclear warheads and a stupid amount of penaids, and launch them so all reach the lunar colony at the same time.
The sheer number of projectiles essentially guarantees that a significant number will impact the colony, and also that one of those that impacts will be a nuke. Yes, using penaids lowers the actual payload weight and thus limits the yield of the nukes, but you don't need a powerful nuke to do a lot of damage.
For example, each of the UK's [Chevaline](https://en.wikipedia.org/wiki/Chevaline) weapons contained 3 nuclear warheads of 200kt each and 27 penaids. A single submarine was able to carry 16 of these, which means if all were launched simultaneously, the target would have 480 projectiles to deal with. 200kt sounds like very little, but as [this article](https://www.wagingpeace.org/the-effects-of-a-300-kiloton-nuclear-warhead-detonated-above-washington-d-c/) demonstrates, a warhead of such "limited" capacity would still devastate an area of ~5km diameter. If the target should happen to be in a vacuum, the radiation emitted by the blast [would be the most deadly aspect](https://history.nasa.gov/conghand/nuclear.htm).
Resources would not be a problem because, guess what, we already have thousands of ICBMs with thousands of nuclear warheads sitting there ready to be reused. In fact I'd wager that current ICBMs could, with some modification, be repurposed almost as-is to hit the moon - all they need is a bit more power to get into a lunar trajectory, and perhaps a new more efficient type of fuel could supply that? Alternatively just scrap the ICBMs and use those raw materials to build your moonkiller missiles.
I'm no general, but if I had to choose between a single "undetectable" weapon that didn't exist yet and could still be shot down; or a large number of proven, easy-to-manufacture weapons that are effectively guaranteed to hit the target... well, I know which option I'd take.
[Answer]
Everyone thinks so complicated.
>
> They are quickly reaching
>
>
>
Means they are not yet 100% self sufficient. Hide the nuke in one of the last supply drops, done.
[Answer]
As far as I know, "no stealth in space" is for manned, actively fuel/computer using operating systems. If you used vacuüm tubes with a magnetic rail system (and on the moon its easy to get it vacuüm) you could launch projectiles out of the moon's gravitywell and into the earth's gravitywell where gravity will do the rest with practically no working cirquitry. It would be harder to make sure the projectile remains undetected as it enters the atmosphere but depending on the speed it might already be within the 15 minute range.
The Moon is likely going to be build for space exploration and exploitation (like astroid mining) in the first place so the space industry there would be big and the people living there some of the smartest hardworking and physically capable people you can find. So they'll have a huge advantage. Missiles from earth would either need to be under constant acceleration for the moon or would be launched when the moon is incapable of seeing the launch site after which the missile is going in increasing orbits until it gets close to the moon, making it easier to detect incoming projectiles as they are either burning fuel or coming from a specific direction at calculable intervals.
Another thing is radiation. The Moon people would be completely set to deal with all the radiation in space, so all the fallout of nukes would be far less impacting (but the low population and depressurization would counter this quickly).
[Answer]
Just throwing in some ideas for others to process further (and maybe approve or disapprove with sources):
* Wait for a time when Earth and Moon travel through an asteroid belt. Place a warhead concealed as rubble/asteroid in earths shadow into belt just barely outside of collusion course to the moon, so it wont be considered a threat by lunar scanners. When closest, start thrusters and hope it can reach surface.
* Nuclear explosions in earths atmosphere cause an EMP. What happens with nuclear explosions in orbit near the moon? A successfull EMP against the moon would render it defenseless. A second direct warhead or troop carriers now should be able to make contact.
* For centuries there have always been ways to win against impenetrable defenses: weakening it from the inside via sabotage, espionage, infiltration, distraction, psychological warfare and so on. The weakspot of human civilisation is the human himself. Let your warhead do the rest
Edit: unfortunately unable to comment this instead of answering due to lack of reputation (new stack guy here)
] |
[Question]
[
Quick summary: it’s the modern day, and everyone can use magic. Some of that magic is of the variety that lets you launch energy blasts from your fists, similar to a Mega Man style arm cannon. You mentally activate the ability, clench your fist, wait for the energy to manifest around your arm, hold it at the ready for as long as you like until you’re ready to fire, then mentally release the energy to shoot.
What I’m thinking about regarding this is what the proper shooting stance for this sort of thing would be, the sort of thing professionals like police and soldiers would be taught. My immediate instinct is that since there’s no recoil necessitating the two-handed pistol stance, the proper stance for using magic like this would be sort of a one-handed archery stance where you turn your body to the side to keep as little surface area as possible facing your target. Am I wrong? Is there another reason people are taught to keep one arm bracing the arm holding the gun besides recoil? If so, what would the actual best stance be?
[Answer]
Seems to me that the most stable way to aim one's arm would be something like this:
[](https://i.stack.imgur.com/Ry3t7.jpg)
Where the support arm wraps around the torso and under the aiming arm. One can then stare straight down the forearm for aiming and, since you mention in comment that the direction of the wrist doesn't matter, the wrist can be dropped slightly to not impede vision.
The torso can pivot in this position from a side-stance shot (exposing the side to the enemy) or a front facing shot (exposing the front to the enemy) so, either stance could be used based on one's armor or cover.
The kneeling version of this would be the same or would use the support arm as when using a rifle - anchor the elbow on the up knee and use the support hand to brace the aiming arm.
The prone version of this needs to change somewhat. The support arm would anchor the elbow to the ground while using the support hand to rest the aiming arm, similar to how the support hand aims a rifle in the prone position.
[Answer]
Yes, you are right. Under those rules, aligning hand (or arm), shoulder, eye and body in the straightest way would be the best posture for accuracy.
Essentially the postures adopted by Olympic handgun shooters or archers:
[](https://i.stack.imgur.com/Z0Tm3.jpg)
But we can play around a bit.
You said that you have to accumulate energy around the arm before shooting...
* **How accurate are those shots?**
If they have a wide dispersion, a stance for accuracy may matter less.
* **How bright is that energy?**
Bright enough to be like having a lantern aiming at your eyes and you'll blind yourself shooting like Mega-Man (and Mega-Man projectiles seem very bright!).
That would mean you would want to channel energy outside your view range and then aim and release with the quickest motion possible.
On the other hand, sunglasses. Maybe they are even more common than reality, maybe they are combat gear and wearing one is a sign of imminent hostilities.
* **Does that energy 'rattle'?**
Maybe that energy doesn't accumulate peacefully around your arm, but it's more like a violent storm and you can't avoid having it jerk your hand around if you aim like an archer.
In that case you may need to adopt a more stable stance and grab your arm/wrist.
[Answer]
In real conflict your most ideal position is always prone. Barring this, any position behind cover. This is for a few main reasons:
* Increase accuracy in shot (a steadier arm) and therefore greater range
* Reduced profile to the enemy
* Greater ability for stealth
No-one uses pistol stances anymore - it is simply not practical as you present too large a target.
You need to move from cover to cover. Anyone caught out in the open, standing, or walking will be noticed, and of course easily targeted.
A prone position is this:
[](https://i.stack.imgur.com/2OpMy.jpg)
Even when a recoil-less rifle a prone position is desirable. If it is not practical due to obstructions or terrain, a semi-prone position is desirable, like this:
[](https://i.stack.imgur.com/9Uvxo.jpg)
It matters little if your arm is the weapon, or if you are wielding arms. The priority in a conflict would be the same, you need to increase your chances of survival.
I remember a Navy SEAL saying that you *have* to go to cover. Anyone caught in the middle of the street has too high a chance of being killed. Even when you move you squat to reduce your profile. Having said that, mobility and awareness are greater issues, being able to move quickly to a position, in a way where your opponent does not know where you are, but you know where your opponent is. But that's a whole book...
[Answer]
Kung Fu stances.
If you are going to shoot magic missiles during a fight, you may take a page from the Avatar series of cartoons. Martial arts classicaly train you into stances that diminish your profile and vitals exposure to attacks. Your aiming and shooting would also flow with your other movements, and this would sinergize well with hand-to-hand combat too.
You can also mix those martial arts and change stances as needed. Airbending is the most focused on evasion and dodging attacks, firebending is the most aggressive art and earthbending meets attacks head-on.
For reference, those arts are based on real life martial arts:
* Firebending was modeled after northern shaoling Kung Fu.
* Earthbending is hung-gar, mantis and tiger Kung Fu styles.
* Waterbending is based on Tai Chi.
* Airbending is based on Pa Kua (also spelled Bagua).
You can see more on the martial coreography of the series by looking for "avatar creating the legend" on Youtube. The movements were modeled and supervised by a Kung Fu master.
[Answer]
The two-handed stance might still be the best option for precision shots and sideways stance the best option for aiming.
Try taping a laser pointer onto your arm and aim at one point for a few seconds. Now imagine not having a tiny red dot indicating the point you're aiming at. Depending on how far away your target and how big your magic blast is, a few millimeters off in your aiming stance means your shot lands several inches off target.
Archers stand sideways because it's the best stance to line up the arrow with your eyes to make targeting possible. It also increases the distance you can draw the string and thereby the force the string puts on the arrow upon release, but that is outside the scope of this question.
For your magic shot that means:
* If it shoots in the extension of your forarm, a sideways pose makes aiming easier because your eyes are in line with your shot.
* A two-handed pose improves stability. A two-handed sideways pose might be awkward enough to negate the stabilizing effect.
* If you can control the direction of the shot mentally it doesn't matter which pose you choose.
[Answer]
>
> Is there another reason people are taught to keep one arm bracing the arm holding the gun besides recoil? If so, what would the actual best stance be?
>
>
>
Control. Two sets of muscles puts less strain -- and thus less possibility of "jitter" -- on each muscle.
But it takes for granted that handguns have front and rear sight posts for aiming. Your arm cannon won't have that; you'll have to shoot it "sideways", and aim like it's a shotgun (which has only a front sight, and not a rear sight).
[Answer]
The more stable a platform you can provide for your forearm, the better you can stop it from "wobbling".
Bracing with the other arm could help.
Lying with your feet toward the enemy and bracing against your legs might help even more.
(Look up the Creedmoor position and the "dead frog" shooting position, for example.)
But you might decide that creates too much risk of hitting your own legs with your own energy bolt.
If the direction of the bolt is determined by the alignment of the bones in your forearm, you have the problem of aiming, because your forearm is not equipped with gunsights and it is hard to get your eye in line with it.
You can use something like the stance in Hueco's answer to press your upper arm against your face and get your eye close to the axis of your forearm.
You can also lie down at an angle to the direction you want to "fire" and press your face down on your shoulder to get your eye nearly aligned with your forearm, placing a hand under your arm to brace it against the ground.
But what about adding artificial sights? If you clamp a sighting device to your forearm, will that interfere with making the magic bolt? What if you have a surgeon graft ridges of bone onto your radius so that you have raised points on your skin that you can sight along?
---
Regarding the doctrines of facing the enemy in order to minimize the number of organs hit by one shot or to take advantage of body armor,
consider how the use of magic energy bolts changes the tradeoffs.
What is the nature of how the bolt injures someone, and how can you minimize the risks?
For example, I suspect that part of the thinking behind "only let them hit one vital organ at a time" is that nowadays you might survive being shot in one vital organ. In the 18th century that was generally not possible, so giving your opponent one chance to hit two vital organs at once would have been better than giving them two chances to hit just one of the organs.
But now that you're throwing around magic energy, how much does it matter which way you are facing an incoming bolt?
Can you provide any kind of armor or magic protection against it, and how does that work?
[Answer]
The one handed stance is probably the best for the reasons you mentioned. Less body area facing the opponent which is good for defense. Alternatively, if you have a shield spell in the other hand being face on has an advantage where you stick your shooting hand through the defensive spell.
Another concern is do you sight along your arm or hand (or finger?) to aim the spell. Is there a pinky spell? How do you sight the ring finger containing the mythical vein straight to the heart? Most likely firing the spell will be arm up so you can see where you aim. If guidance mid-flight is possible shooting from the hip might be a better option to disguise the intent.
In a world where everyone runs around with hand cannons defense becomes far more crucial.
[Answer]
Ignoring the rest of your body: right in front of your eye, so that the hammer/butt is touching your cheekbone.
It would (probably) give you the easiest way to site.
With a real gun, holding a gun there would break multiple bones in your face.
[Answer]
The marksmanship principles would still apply:
* Hold must be firm enough to support the weapon
* Weapon must point naturally at the target without undue physical
effort
* Sight alignment must be correct
* Shot must be followed through without
disturbing the aim
The amount of recoil only actually affects the last principle - all of the others are *before* the shot. These principles apply whether firing a .50BMG rifle or a .177 air rifle, and it's worth noting that the firing positions are very similar for both. In order to be accurate, you need to hold the *mass* of the weapon (and indeed your arms) steady in order to line up the sights, regardless of recoil.
So overall I'd say that the ideal firing positions would be the same for a recoil-free weapon as they are for any other similarly-shaped modern weapon.
] |
[Question]
[
You're planning to move to the rich country of Lycania (*names are a work in progress, ok?*), a country as big as the USA plus half of Canada, where you have been offered a good position which would make you earn far more than your current job, giving you an alternative to a mediocre life. Lycania is the one true first world country in a slowly decaying world, and there are people who would [literally] kill to live there.
---
The catch: Lycania's original inhabitants are werewolves. While most of them are quite accustomed to their culture and remain within their isolated nation bordered by snow lands to the South, and at North only the sea, immigrants go through the struggle of fighting for survival once a month.
The amount of control Lycans have over their wolven self is not uniform: some rely purely on animal instinct, some have a great degree of control on their monthly powers, turning said control sometimes towards avoiding beastly actions, in other cases towards evil uses. The Lycan governement limits the amount of damage by doing all they can to limit access to government owned dangerous facilities and equipment (military vehicles and weapons primarily), but in this society of natural hunters guns and other simple weapons are not that hard to come by - think USA - as if the werewolf nature wasn't enough to make them dangerous.
---
You want desperately to take the job, but you wouldn't mind surviving decently past the age of <*insert your age here*>. **You (individually and/or via your employer who will likely offer a solution to help you as part of the benefits) need a plan that can guarantee you high chances of survival (>90%) for multiple full moons** - ideally an infinite amount of them, but if you make it for a few months you'll have been around long enough to find alternatives as well, and will have saved enough to have better alternatives.
As it may have a huge impact, you can consider two separate cases:
1. Your means are such that your purchase power and connections are those of an **average working class person**
*or*
2. You are already **considerably wealthy and well connected** (this implies that the job in Lycania would make you filthy rich in a few years' time by the way)
---
Some further points and requirements:
* You could aim to become a werewolf, but either you don't want to or the risks are too high (*because I said so... i.e. I don't know the official reason yet*)
* Werewolves are humanoid wolves with prehensile hands, or forepaws, who can move both on 2 and 4 limbs: they can get as big as 115% of their human version (that approximately applies to both size and weight)
* Silver (as well as garlic) is not lethal to them on a regular basis, but it is essentially an allergen to which all werewolves have some type of reaction ranging from mild to very strong; there seems to be an inverse correlation between the amount of control Lycans have during full moon, and the strength of their reaction to silver, so instinct driven Lycans will generally avoid it
* They can be killed with regular weapons but will not be slowed down unless their limbs are seriously maimed, or a vital organ is hit, otherwise they will heal much faster than a normal human being
* The transformation happens for all werewolves on the night when the moon is at its fullest, from dusk till dawn
* You have some time (~ 6 months) before you start working, and your employer is willing to arrange flights in and out of Lycania for you during those months to get settled, as they understand outsiders' needs
* You can rely on passive defences (think fortified apartment/house) or active ones, and combine them together as needed: do keep in mind that some resources are finite, e.g. bullets, and you cannot easily rely on just having enough of them
* You can hire contractors, bodyguards, and so on, but a) if they're non-werewolves they're usually extremely highly paid professionals, b) if they are werewolves, they may be of the evil type and turn their knowledge of the work you had them do against you
* You don't have the option to leave the country just before full moon: planes and ships out of Lycania are much less frequent and more expensive close to a full moon, and priority admission is granted by the government
* Very tall mountains, very big lakes, or the sea, are not easily reachable from where you will be living, unless you have a specific plan in mind
* You can rely on leaving work earlier than usual on the day before a full moon: 3pm rather than the usual 5pm; you cannot however plan on taking one or more days off work every month
* There is a small police and army force of Lycans who know how to control their instincts, however that alone takes most of their willpower, so that they are not really effective in restraining other werewolves
* If a Lycan of the evil type has anything against you they will likely try to harm you during the night, as finding proof of their actions will be highly unfeasible and as a non-werewolf you are easier to find and attack than others they may want to hurt as well; remember that this type has a still functioning human intellect and can rely on tools, vehicles and weapons if necessary, as well as make plans and form packs, so simply locking yourself in your house is not reliable enough
* The technology level is very similar to that of "our" 2015, the main difference being that medical solutions to inhibit or control the transformation are being researched, and that tools for restraining werewolves have been invented throughout the ages: these are nowadays mostly produced and used abroad, or by families with difficult pups... errrr, children
*I will edit/add to these if necessary, please point out if you believe they're not consistent, or lack something, as it's still a work in progress*
[Answer]
In a world like this, I think that the employer would sort out most of the security:
1. **'Normal' Humans would be in demand:** consider that, once a month, all of society breaks down for an entire night as everyone goes completely insane, then suffers amnesia about it in the morning. There are some people who only go a *little* insane, but they're indistinguishable from everyone else. So, if one of these individuals with heightened control does something "evil" during that time, they're no more culpable than anyone else. On the other hand, there are some people completely immune to this monthly insanity! An employer would want to do everything they could to ensure non-lycans were protected, as they'd be able to keep working even when everything else was shut down (it sure would suck if your server died during the full moon, and no one could look at it for a full 8+ hours).
2. **'Normal' Humans would be dissuaded from losing their normality:** If an employer in a country full of werewolves went to the trouble of hiring an importing a normal human, they'd probably have that normality as part of the employment contract. After all, what's the point of hiring someone immune to the monthly insanity if they just go ahead and infect themselves with it? This would give the protagonist plenty of motivation to remain completely human, even if the option to become a werewolf were to present itself.
3. **The employer would ensure safety:** So, given points 1 and 2, a reasonable step for the employer would be to offer a safe place to the employee for the duration of the full moon every month. However, this would come with the condition that the employee would be *locked in* for the duration. This would also protect the employer from having a normal human ransacking the place while everyone was wolfed-out. There is already a real-world parallel for this: overnight retail workers are "locked in" at their workplace; they can open the door, but doing so would set off an alarm. This prevents them from letting in unauthorized persons, or from entering unauthorized areas, barring an actual emergency.
4. **The logistics of safety:** Assuming that the werewolves in your story would have the standard mythological allergy to silver, then an employer could provide a thick reinforced-concrete room which would keep out just about everything (human *and* lycan), and a silver chainmail-type suit for emergency protection. Fully covered in silver, a human would be immune to any attacks from a nude werewolf. If the wolves know to avoid silver due to its odor, then the human could just be given a colloidal silver spray deodorant/pepperspray that would basically be a cheap, disposable werewolf repellent.
[Answer]
**Use a bomb shelter**
The way you describe your werewolves, this doesn't actually seem to be that big of a deal. They are not werewolves for very long, only one night per blue (okay, full) moon. As such, you only need to deal with the problem once per month at most.
A bomb shelter that can only be opened from the inside once it is locked would be the obvious solution. The main problem with bomb shelters is that you can't keep an infinite amount of water or food down there, but this isn't a problem when you only have to stay there for a single night.
Just keep proper track of when the moon is full, head home earlier that night and lock yourself in your bomb shelter. Then the next day you come out, replenish your supplies and keep living your life normally until the next full moon.
**However, don't use a group bomb shelter**
After some comments to this question, I'd like to add that you should not make use of a group bomb shelter. You want your own one for just you.
You might get locked out of a group bomb shelter if they decide to close early because of werewolf related paranoia, or one of the members who enter might be a werewolf undercover, or infected with lycanthropia without even realizing it, which would lead to a lot of humans locked in with a werewolf.
[Answer]
**Bathysphere**
Make a simple bathysphere from stuff you find in the junkyard. Anchor it to the bottom of the largest body of water you can find or make. Advantages:
* The submerged bathysphere is very hard to spot in the moonlight, even if you know it's there. Murky water can further camouflage it.
* Your scent will not leave the bathysphere.
* There is only one point of entry.
* Firearms inside the bathysphere work much better than those on the outside.
Unfortunately, the bathysphere is weak against ghetto depth charges and scuba-wolves with cable cutters. Ideally you'd put your bathysphere in the ocean, since werewolves can't stand salt.
[Answer]
Air balloon!
I was considering boat, but there might not be lakes, and werewolfs can swim! But they sure cant fly, and probably can't operate air balloons.
So I'd go for air balloons. If there's simple gun powder weapons around then I'm sure someone would have invented at least a crude and simple flying device for this kind of situation. It would only really need to be flying for a night, and if you bring a friend then you could take shifts making sure it stayed floating.
The downside
A) Needs gas
B) unless you're an actual pilot who intends to steer the balloon all night, you need to tether it to the ground so you doesn't fly away. Unless you would want it for a traveling reason, it would make sense to just have it tied to your house roof or in the garden.
C) a smart and strong werewolf would know to just pull your ship down with the rope/chain, or even climb up the rope. Or be a d\*ck and cut the rope and then follow your balloon on foot until it crashed (if the balloon is not steerable/no pilot) at the end of the night
[Answer]
There are a few things to consider in a world like this that haven't been explicitly mentioned:
A. If lycans are normal 29 of 30 days and normal humans are getting paid an exorbitant amount of money to work here (more than lycans?) then it's likely that their job entails something that the lycans cannot easily do themselves - such as maintaining systems, order or some other critical component to the countries survival during that one night.
This probably means that the normal humans are actually expected to work through that one night, and survive to do their job. Employers would have a very vested interest in their survival in such a case.
B. If the law of the jungle is an accepted part of society for the one night per month how does the society itself hold together and maintain their own population to still be considered a first world nation. Killing each other off en masse on a monthly basis would deplete the population considerably faster than procreating - since a baby (even a litter if they tend to have multiple babies) must survive several of those nights - and so does the mother.
The society would have a significant interest in providing safety to its own lycan population is if didn't want to eliminate itself in a few years.
C. Lastly to become a first world society really does require law, order and peace. Every one of our useful inventions have been created because someone intelligent was safe long enough to create the idea. We wouldn't have guns if someone wasn't safe long enough to experiment with gunpowder. We wouldn't have swords if someone wasn't safe long enough to learn to forge them (and then actually do it). We wouldn't have concrete buildings if the workers were killed off once a month or the project was bombed by "evil Lycans" before its completion.
---
All of those things suggest that a potential human employee would find themselves in one of two positions during a full moon.
1. They're in a fortified, human work environment for the night to get their critical work complete.
2. They're on the offensive anyway, acting as an extremely well equipped police force or military to keep the aggressive lycan population in check so that society doesn't tear itself apart by morning.
[Answer]
Get yourself a couple of Siberian tigers, and you will sleep like a baby. Apparently, the Siberian tiger is the only natural predator of wolves. It's uncertain if this includes werewolves, but it is probably safe to assume that your average werewolf is not going to take on a tiger. Wolves are crafty, and they will coordinate their attacks, so make sure you have several tigers. Put up a big fence around your house and let them roam around the yard. It's not really practical or economical to keep the tigers around all the time, so put them "on loan" to the local zoo and retrieve them when you need them.
[Answer]
I would lock myself in a very secure survivalist-style hole-in-the-ground bunker for the night. Obviously i'd want internet in there.
[Answer]
There are other non-werewolves living there, you said. Ask them how they manage. It seems to me that either the werewolves are going to be smart enough not to invade the home of someone with a high-powered rifle, or they’re going to be way too dumb to figure out a way around any reasonably complicated defense. Either way, lock yourself in. Safety in numbers (unless one of that number got bit and didn’t tell you).
Something non-lethal, like pepper spray, seems like a good bet if somebody he cares about goes wolf around him. There are real cultures that, say, held pogroms on Easter, so it’s possible that the werewolves just let each other get away with that, but it has to be inconvenient enough for people to keep dying, when they’re paying top dollar to recruit immigrants, that there’s got to be some kind of system in place to stop that from happening over and over.
[Answer]
Well i'm not that much deep into the werewolf subject but as a kind of inspiration, here are some points:
* I would probably try to find out if there's a non werewolf community at the place i'll work and for at least the 1st full moon try to provide some bodyguards (I'd prefer non-werewolves) or at least weapons. Therefore i would try to start my job just after the full moon has passed:
The community could be a solution to help each other: For example they could escort each other home to work and take a day off in turns so that for example the last to come home has an escort!
* I'm not sure if you pointed it out but can one buy weapons when settled down in Lycania?
Then i would spent a part of my income to get some weapons
* An other point what if for my self defense i injure a Lycan would he be angry at me after full moon?
This could be a problem between Lycans and emigrants!
* an other point what if during full moon i just stay at work and settle down their?
This would mean a few days before i would install a bed or have it always in my office and buy enough food to survive as i guess the working place would be secure!
* About medicine is there a possibility to use a kind of weapon which injects a kind vaccination or injection which might either make raise the control a werewolf or freeze their body movement for a while (as a clean weapon)?
* *But why the employer doesn't care for the employees safety?*
[Answer]
**Use active and passive measures along with area denial to prevent attacks**. It is better if you can defeat a werewolf attack before it even starts. You don't need to make your house impenetrable, but strong enough that a werewolf or team of werewolves can't breach the defenses in a single night. Or build the defenses in such a way that a werewolf will find it easier to look for prey somewhere else first.
Basically, living in this country will be like living in a warzone for one night a month. Every defensive measure taken by a modern military to defend an outpost is appropriate for this answer.
**Area Denial**
As the locals if there are any smells that werewolves don't like or just simply cannot tolerate. Spreading strong scents such as cayenne, mouthwash or vinegar are your home may repel a werewolf. Experimentation will be needed to find out which smells are most effective. The locals probably have a good idea.
*Ultrasonic howlers boxes* should make it uncomfortable or downright painful for werewolves to come near your home.
**Active Defenses**
Pack in lots of anti-werewolf ammunition, a fully automatic weapon and plenty of caffeine (adrenaline may be high enough you won't need coffee) for a long night. Make an obviously weaker entry point that forms a choke point. If the werewolves can only attack you one at a time then it's easier to defend yourself.
*Fire weapons* Make a version of this [car-jacking prevention,](https://www.youtube.com/watch?v=LQbHnLSasfQ) only mount it to your house.
*Traps* Every trap imaginable.
**Passive Defenses**
Physical barriers such as fences, bunkers, barbwire or spikes can be combined to prevent a werewolf from getting too close and can be used to create your own kill zones.
**Broader Cultural Implications**
A trade-off these werewolves need to make is whether they want to roam free on the full moon or if they want to sequester themselves. If they roam free, they are subject to being killed as one might kill a dangerous bear or lion. If they sequester themselves they don't have to worry about being killed. This arrangement offers legal protection to normal humans who kill a werewolf on the full moon. (I don't know if it would count as murder, man-slaughter or some other offense.)
[Answer]
The bomb shelter answer is already great, so only a few improvements:
* Build your shelter alone (arrive directly after the full moon to have full time) and build it apart from your normal home. Perhaps you could build a long concealed tunnel from your home to the shelter which allows you a) an escape in a surprise attack and b) an escape if your shelter has been detected. Use every measure to be sure that your track cannot be scented.
* Your shelter is a mix of a panic room and a sniper hideout. It is a sniper hideout because it is extremely well concealed (Some real hideouts are tested by soldiers who are given the approximate location and still cannot find it, inform yourself about these in the internet). And it is a panic room because it is build underground, consists of strong ferroconcrete and a reinforced steel door. The door is airtight so you cannot be smoked out and consists of two separate steel layers with a fireproof concrete layer inside (It contains basalt which melts to a viscous unassailable mass when attacked with a blowpipe). You get air from several well-hidden vents which can be closed when detected.
* The last ditch defense is weaponry, but it should be avoided as last possible option because you are in the minority and cannot afford to fight. One silent/long range weapon like a crossbow or compound bow (take out single enemies to clear the escape path), one deadly medium range weapon like a shotgun with 00 pellets or a .357 magnum with hollow-point ammunition (you have been detected and need to fight) and one spear/sword (you have a good chance to survive, but an (already wounded ?) enemy charges you and you need to keep distance).
[Answer]
Your employer could mark you as their territory much like a dog would, which would cause most Lycans to leave you alone.
You could say the Lycans are purist and don't want to mix breeds, so instead of turning into vicious animals that simply kill just to kill, they seek out humans and eliminate them to reduce the chances of someone reproducing with a human.
As a "marked" human, you are the responsibility of the "marker" and if you do anything you're not supposed to, like breed with Lycans, then you and the marker will be eliminated/banished.
Conflict could also arise when your employer turns the act of marking you into a bizarre sexual thrill and it freaks you out or the situation becomes dangerous, but by this point you're already settled in so you either just try to fend for yourself or find someone who will simply mark you without creating more problems.
[Answer]
>
> **You don't have the option to leave the country just before full moon: planes and ships out of Lycania are much less frequent and more expensive close to a full moon, and priority admission is granted by the government**
>
>
>
I don't see how this limitation would stand for very long. It doesn't make sense (Assuming you have a free market economy.)
This indicate to me that the law of supply and demand has gotten severely out of whack. There is a lack of supply but obviously a lot of demand. When there is an under served market with lots of demand, someone will step in to serve it.
This situation just needs an enterprising company or individual to schedule lots of chartered flights (fully booked) out of the country every 29 days. I mean if I were running an airline from almost every other country in the world I would just capitalize on that once a month, (scheduled & predictable) bonanza of demand. Travel in the rest of the world would pretty much cease for a few days everywhere else.
If you take it one step further... You could have the government make it a requirement that everyone (human) have a "full moon evacuation plan" kind of like a health plan (because isn't that what it is after all)
You could even set up subsidies for those who might not be able to afford it and online exchanges where people could choose from different evacuation providers.
Oh wait that last part sounds vaguely familiar.
[Answer]
Multiple people have suggested bomb shelters. I think there's a perfectly viable answer that doesn't go quite that far and is far more livable:
Concrete dome houses. Normally they are built with windows as per normal building codes but in this land I think a windowless version would be acceptable. You have a very tough door. They'll withstand anything short of the heaviest guns available to civilians (and even if a bullet comes through it's obviously unaimed and thus a very minimal threat), they'll shrug off any civilian low explosive device and it will take a fair charge of high explosives to breech them.
Current versions are ordinary houses inside other than the shape of the roof, this wouldn't be something you have to retreat to.
If this isn't enough defense take the same thing and bury it. Ideally, place it inside a hill and then replace the dirt so that while it's buried it's still at ground level or even a bit elevated. (Going entirely underground brings up drainage issues.) Build shotguns into the entryway that can be fired from inside--if the wolves try to force the door you turn the entryway into wolf steak tartare.
Again, these exist in the real world. They're much less common because normal building codes do not permit living in such a structure but it certainly would be possible to design such a structure with an acceptable means of fire escape. People do it because if you put a moisture barrier in the dirt over the dome and bury suitable air ducting in the ground you can build a house that doesn't need more than a fan to provide heating and cooling.
Given the werewolf threat I would expect at least the former to be the normal means of house construction, acquiring such a place should not be a problem. (Economically they are close to competitive with conventional house construction techniques and by the time you look at life cycle costs they're cheaper.)
[Answer]
In a first-world country with a healthy population of werewolves, I think that we can safely make the following assumptions:
1. The the governing powers have established ways to survive a full moon while protecting their assets, both material and human.
2. The intelligent werewolves have permeated every level of governance. Lets face it, they're just superior to humans in every way.
3. The top levels of Governance is exclusively werewolf. This is why they allowed the other, lesser werewolves to exist in society.
4. They need a healthy intermixing of humans in society to sustain themselves.
5. Human/werewolves violence is carefully monitored and any serious threats to stability (both from humans or werewolves) are dealt with.
6. A balance of power and respect for authority has been achieved.
Without these elements, a werewolves populated first-world country would quickly become a third-world country. We can also assume that:
1. There are high class protected humans and there are feed-stock humans. You want get above that cut off line as soon as possible.
2. Violence will be met with violence, so killing werewolves is not really an option.
3. Intelligent werewolves will protect those of value to them. You need to find a way to get on the good side of someone important, and make them see you as more than food.
**My favorite Option: Get into the werewolves entertainment business!**
During a full moon, entertainment tastes shift. Standard forms of entertainment just don't satisfy 'those' needs, even of the most intelligent werewolves. All of them will be wandering about looking for some way to satisfy themselves, after they have eaten their fill of humans. Sadly for them, normal TV dramas are somehow unfulfilling and those bowling gloves don't seem to fit anymore. So here is what you do:
Start pitching grotesque yet intellectually stimulating entertainment concepts to local investors, perhaps a shakespearian battle arena or a reality show where you hide the blood. Eventually you will catch the knowing eye of an intelligent werewolves who feels the pain and boredom of long moon-lit nights where whole-sale violence is just not an option. Find a way to get your project moving, then work on an important part of it. You may not be the project owner or manager, but that does not really matter. Your aim is to improve your survivability. Do a good job and you will find yourselves rubbing shoulders with the elite in an emerging entertainment business. With some hard work and politicking, you will eventually find yourself in the protected crowd. You may also be given the opportunity to become a werewolves (in high standing.) Either way, entertain the elite werewolves, integrate into their society and protect your position. Then, you should live a long and happy life.
However, there is no faster way to be murdered by the masses than to produce sub-par werewolves entertainment. You have been warned!
[Answer]
**Measure from preventing a werewolf to harm someone else:**
If the werewolf society knows that the full moon has **no usefulness at all** then werewolves can happily self provide measures to avoid harm someone so they can apply the measures before going on full moon.
In example silvers revested straitjackets. They have to be crafted with the size for each werewolf, when they turn into wolves the increase of size tightly bound the jacket not allowing movement and the silver does not allow to bite-away the jacket (note that silver is outside the jacket, not inside, that at same time prevent also another werewolf to help remove the jacket).
**Measures to protect humans:**
Depending on the strength of werewolves a reinforced home/ transport vehicle can be designed. I don't see why people insist on having concrete homes with no windows, a werewolf cannot have unlimited strenght so there will be always strong enough materials that can avoid to be broke by a werewolf (there exists in example transparent materials much more resistent than concrete that would allow to make vehicles and windows).
Depending on the quantity of humans we can have from small cities to big buildings where each door automatically lock during full moon and can be opened only if people on both sides press the "Open for 3 seconds" button. The important part is having each room isolated to avoid spreading of wolves (like sectors in submarines).
We can have also locked rooms for vehicles that can't have both entrances opened at same times (like in banks) so that one can enter the shelter even using a vehicle.
**Law && crimes**
There will problably be laws preventing both humans to hunt wolves, and forcing wolves to do all they can to prevent harming humans during full moon and like every law there will be people breaking the law:
1. Werewolves will act to close themeselves in shelters while in reality the shelters may have a illegal secret exit
2. People go killing werewolves that is trapped in shelters
Note that shooting at wolves on open spaces or inside human's reserved buildings may be allowed or not while killing a wolf even for self-defense in a forest may be considered a crime (you should not be in a forest in first place)
In practice there are many possible ways to make that coexistence possible from a logistical point of view, the interesting stuff about that situation is more from political and social point of view.
**Social phenomena:**
People that want to be rich spend time to research safety measure, werevoles are forced by law to use safest measure and hence once someone develop a new safest method (prooven to be safer) werewolves are forced to buy it this would also give a valid excuse for rebel werewolves and cause political friction between werevolfes' nation and humans' nations.
Note that this is actually similiar to what happens already in our modern society with guns & pharmaceutical companies and also with banks (debt)
**Games:**
Depending on society it is possible to assist to Arenas where humans have to survive the Full Moon (maybe sponsored by producers of safety measures^^). Games may cheat causing political problems (in example fully self controlled wolves that don't wont to kill humans even during full moon are massacrated by people with powerfull guns).
**If Full moon is necessary**
The fool moon may be necessary to werewolves life cycle (in example the reproduce only during full moon, in that case their society would not have something like Porn industry). Werewolves will be less interested in finding solutions for coexistence.
**If full moon is not necessary**
Proably in that case werewolves are interested in finding solutions to their "problem"
What seems really interesting is finding a realistic reason for wich werewolves may need humans (the server downtime is not a problem because if the server is down for 8+ hours there will anyway be no one able to use it because both users and developers are turned to wolves).
[Answer]
Having the benefit of reading a bunch of the answers already posted here is nice. My thoughts so far:
* Commercial safe rooms are designed against well-armed humans entering. If there's anything like that in this world, I'd go for that.
If not, I would prefer for a safe room:
* steel reinforced, concrete, fire-proof (in case they set the house on fire to get you to come out, if they are (in the worst case scenario) sentient, amoral sociopaths on that night, or in case they cause an accident by knocking over your prized gasoline and open flame collection that you conveniently didn't have time to put away, or whatever), structure with adequate ventilation (the ventilation lines should also be fireproof, and go well away from the property, possibly exiting underwater at your pool filter, which will be bubbly anyways, since if you're well off enough to afford this you probably have a pool), charcoal filtered and strongly scented with unpleasant odors of course. If its mounted at the pool filter the air going out will also reek nicely of bleach. This shelter structure should be built into the foundation.
* live video feed to the rest of the property
* smart house features such as being able to lock / unlock doors to the house - if a werewolf gets inside and gets trapped inside and wants to leave for instance, it would be best to let it go - and be able to shut the door again, as well as monitor perimeter motion detectors and cameras.
* food and radio to be able to help relax.
* alarms that are wired to alert emergency services, blare loud klaxons, and emit odorant fog that smells like the house is on fire - and full of rotting eggs. If there are any known irritants to werewolves in this setting, like colloidal silver, those would be grand as well.
And then...
* Pay a dominant werewolf to mark around the perimeter.
* Lay down an inner perimeter of strong, unpleasant odors, like with 'all-natural' insect repellents, such as garlic, pepperment and so on. Repeat this layering around your safe room.
* Ultrasonic noise generator
* First aid kit
* Fire suppressant.
* Adequate temperature controls integrated with the ventilation system.
* If it gets really terrible outside, provided the structure can take it (and again, it should be able to), set the entire house on fire.
* If werewolves outside of their werewolf time can smell better than a human can, hiring a werewolf consultant to come and smell-check the property. While they're at it perhaps they can advise me about possible modifications to make to prevent entry. This is probably a pretty lucrative profession there. Maybe the same one who is coming there to mark things.
For that matter, ask them to come back on a regular basis and re-mark.
* A fast acting anaesthetic dosed appropriately for each family member, for if the worst should happen. Rather than cyanide capsules because I don't want someone killing themselves out of fear that the werewolves are going to break in if the werewolves are not genuinely going to break in, but I do
want them to avoid pain if possible.
* fixed curfew: Although we wouldn't bar stragglers from getting in to access a shelter (things happen) we'd expect people to be there by a specific time and to lock themselves in by a specific time. Everyone would lock themselves in.
* spray the threshold after passing. No use laying down new scent.
* Lights out and try and be in shelters before moonrise.
* timed locks: IF werewolves are sentient but evil that night, or have human helpers, I'd spring for timed locks as well, that only open hours after sunrise the next day, to prevent hostage-taking from getting us all killed out of sentiment.
* maintainance: test equipment regularly to make sure it works.
* Periodically (every three months maybe), do a complete drill including overnight lockdown, and staged 'werewolf' incursion.
---
Things I wouldn't do:
* Eat wolfsbane. Sorry, aconite / wolfsbane is a deadly poison in real life. Don't eat it, no matter what you see on Teen Wolf. You can totally consume (reasonable quantities) of colloidal silver in real life though. The silver will accumulate in your tissues, making a silver-sensitive werewolf more likely not to take a second bite. It will turn your skin gray, unfortunately (or fortunately if you like playing dark elves in cosplay a lot).
* surround the house with armed people. That's like wrapping it in super aggressive bacon.
* live in a windowless house. If you've got decent perimeter fences, like brick and mortar fences with razorwire tops, decent cameras and motion detectors, and a largeish estate, you can be in your interior shelter before they come to you, if for some reason a werewolf manages to transform outside of /the very night you should be spending the whole night in the shelter/ or you happen to have gotten stuck outside. Might as well be comfortable the rest of the time. I would do like one person said and have only second story windows though, just to avoid the costs of replacing them (hopefully).
* Forget to be home that night: If this place has similar technology to today, I would set alarms on my phone, reminders on my calendar and so on. I would make sure my loved ones did the same.
* Share: If someone wants to spend the night in my property, that is fine, as its better than being on the streets, but the shelter would be single occupation only. Additional shelters as warranted by family / etc.
However the safe rooms are single occupancy only, and its not my spare recroom or bedroom and its not a storage closet. Open it just to maintain stuff in there on a non full moon. You don't want to fix every minor scrape with the first aid kit in there and then not have one that night, or be frantically tossing boxes into the hall when the werewolves come.
* Put too many barriers on the way in: The perimeter gate would be accessible via biometric id (fingerprint), not a passcode or a key. The front door would have steel plate under the wood and be barrable from inside. The code to access the shelters would also be biometric(retinal). I think I would go ahead and have a double gated entrance though. So if a werewolf follows someone through the gate, whoever's on camera duty can close the inner one. Biometric id would also confirm, at the same time, that the thumb or eye used was attached to a living person. I'd also spend a lot of time drilling with everyone on getting into their respective safe rooms. I wouldn't put umpteen thousand barriers between me and the safe room.
* Have the safe room accessible from outside: I am in until I let myself out.
+ No external locks or key panels for people or werewolves to mess with.
* Buy alpha scent over the internet. That is just asking for trouble. Get together enough money, and its probably pretty expensive, to have someone come there and do it themselves.
* I really like the idea of a big freaking Siberian tiger. Its another one of those asking for trouble situations, though. Since I'm not really trained in handling one or certain what its requirements would be, or how to keep it from damaging my house or stalking me itself, it really wouldn't be much good unless it lived in kind of a fenced in perimeter around the property, with an assigned regular caregiver / trainer. It just seems like too much effort spent on defence at that point though. It should intrude minimally the rest of the time.
* Be completely alone: Up until its time to actually get into shelters, it would be nice to have more than one set of eyes on the perimeter that night. It would probably be pretty easy to trade having a safe place to stay that night (one of the shelter rooms) to have someone be a house guest.
* Let my guests run the show: The smarthouse interface would have the capability to both override and lock down smarthouse controls in the other rooms. This would be biometric, via retinal scan. The scan would also verify that I was alive. I want them to be in control in time to say, close a gate if they need to, but if they are about to do something I don't want them to do, I'd like to be able to stop them and do something different.
* Personally, I'd avoid guns inside the house. Its just going to lead to accidents and issues. While the stopping power of a high caliber gun at short range seems really necessary in theory, with good shelter it shouldn't become an issue. Just being outside a shelter with a weapon means putting more human smells into the air. If for any reason someone had to be away from home that night (and it should be a really good reason), then a high caliber weapon - a desert eagle with silver bullets, say - might be warranted, along with (hopefully) other precautions.
---
**Primary points:**
* the important thing is to try to drive them away, and make it seem like you're not an important target.
* easy for me to get into in a hurry, thanks to drilling and design
* Fireproof, not fire-resistant. As in, capable of surviving inside of an active house fire.
* Maintain good smell discipline around that time. Smell barriers have to be maintained, not just laid down once.
* Provide a way for them to get out.
* Two point biometric id, not passwords. You don't want to be killed by foggy memory or slow or sloppy timing.
* Steel reinforced concrete, locks from the inside, can't be unlocked - from inside only - until morning.
* Don't eat poison.
[Answer]
Consume wolfsbane for the two or three days preceding the full moon. You will therefore be unpalatable to the werewolf, who is probably looking for food, not to settle a score with you.
That being said, a revolver with lead azide (exploding) bullets would be easy to carry and an exploded heart will probably prove a serious impediment to the most zealous werewolf.
[Answer]
If werewolves increase in size to as much as 115% merely utilize tunnels that are barely big enough for a human to crawl through. Catacombs might do in a pinch, if appropriately sized. A wealthy person might pay for a custom fortification, where the tunnels come complete with sensors and all manner of traps but the main defense seems to be size.
[Answer]
I would buy or rent a condo in one of the human enclave residence buildings/communities that are basically silver gilded inverse prisons (on lock down once every 29 days that is)
I would sleep peacefully knowing that a screened professional security force is keeping watch over the facility and my locked "cell" protects me from any other residents that might transform that night.
If no one in the country has thought of this, I wouldn't accept the job and instead start a company that builds these.
] |
[Question]
[
These days we have so much street lighting that the stars are blocked out, and cities are easily seen from space. That wasn't the case a few centuries ago. Flyers in the middle ages (witches on broomsticks) would have a nice view of the stars - but would they be able to navigate by eyesight?
I am presuming they would have an easy time when there's moonlight. And on a night with no moon (or a new moon), it may not be pitch black (thanks to sources like [zodiacal light](https://en.wikipedia.org/wiki/Zodiacal_light)) but identifying features on the ground may be problematic, from an airborne perspective. Even in populated places, people did not just light torches 24/7.
[My question from two years ago](https://worldbuilding.stackexchange.com/questions/160327/how-bright-were-medieval-cities-at-night-seen-from-the-sky) is about cities. Time to cover the countryside! Taking the following:
* 14th century central Europe.
* Witches routinely flying on brooms from town to town.
* They fly exclusively at nighttime (sunlight cancels their magic; an untimely sunrise drops them out of the sky).
* The moon might be unavailable, either because it is new moon (few nights a month), the moon is below the horizon, or there's cloud cover.
* The witches fly below the clouds, at about 500 meters altitude. They can ascend to 2km or descend when needed, but they must obviously not be seen. Their cruising speed is 50 km/h.
* There's no spells to improve night vision; they have regular human eyes.
* They don't fly when it is extremely misty.
* The witches may not always personally know the route well, but they can produce their own maps if needed.
Do they absolutely need some sort of ground infrastructure of their own (always-burning torches, etc.) to navigate, let's say from Prague to Passau? Or are there enough natural or man-made features in the medieval countryside that one can see in the darkest nights? I am personally disinclined to give them ground infrastructure but also to have regular witch downtime once a month.
I have considered that rivers and brooks reflecting the stars might do, but I am not sure. The hardest part for me in this light-polluted country I'm living in is to just picture how dark such a night would be, which long-exposure photographs cannot accurately capture.
[Answer]
The human eye is remarkably sensitive. As one who has worked in photographic darkrooms for many years, as well as doing dark-site hobby astronomy, I have experience with this.
First, when *fully* dark adapted, a healthy, well-nourished human can see light levels that are astonishingly low. Even beyond sixty years of age, and nineteen years after a diagnosis with diabetes (known to be harmful to vision) I can still see the outline of my hand in front of a white door in my darkroom, either by light *coming through the door* from the lit room beyond, or by light coming through the window cover (fairly thick plywood, painted flat black on the outside) from the daylight exterior. This is a light level low enough not to fog even fast film in a handling time measured in multiple minutes: photographically, it's total darkness.
Second, my experience in the late 1990s was that, after twenty minutes or so in the dark, I could easily navigate on foot between telescopes and vehicles and people, solely by the light of a clear, starry sky. In fact, I've read that starlight alone, on a clear night, is *too bright* for the eye to fully dark-adapt; that is, there is sensitivity left on the table with starlight only.
On that basis, I would expect that if your broom pilot is fairly young, in good health, and has sufficient vitamin A in his/her diet, they'll be able to see well enough on clear night, even if completely moonless, to recognize major landforms like rivers and mountains (and dark cities), and avoid collision with obstacles if they don't fly faster than a brisk walk (go faster, and collision avoidance becomes a bigger challenge because of the difficulty of identifying what you're almost seeing).
Of course, for a familiar route, one would know how high to fly to made obstacle avoidance unnecessary, and can then fly at any convenient or possible speed. Mountains would be landmarks, not obstacles, for the most part and even today very few human-built structures exceed 300 m above ground height -- which is still pretty low for flight cross country.
[Answer]
For short trips in familiar areas, night vision and ad hoc lights will suffice, see @ZeissIkon 's answer. For longer trips:
## Homing pigeons!
Pigeon post has been a thing [since Old Egypt](https://en.wikipedia.org/wiki/Homing_pigeon#History), and was used in the middle ages.
A problem here is that pigeons, flying comfortably at around 100 km/h, are typically faster than broomsticks, and I see three solutions.
The standard solution is to cast a spell on your guide bird. Depending on how magic works, this could be comparatively easier than making a broomstick fly.
You could also breed slow pigeons, train normal pigeons to fly slowly, or weigh them down.
Third, you could use some other slower bird:
## Ravens!
According to [this paper](https://academic.oup.com/cz/article/62/4/337/1745281), the wild ravens studied move at speeds up to 40 km/h, and would thus be easier to follow.
No mater what bird you use, you need to be able to follow it in the dark.
In the case of ravens, you might be able to train it to keep close enough to follow or make regular sounds. I kind of like the idea of having a screaming raven moving through the night.
Otherwise, you could tie a small bell to the leg of the bird, loud enough to follow but small enough not to draw attention from a distance. Or an enchanted light, whichever is the least conspicuous.
---
In any case, you would need to transport these birds from their home (the destination) to the place you are travelling from. Important witch institutions or even small guilds would have cages with birds from various nearby places (within say 400 km, one long night's travel), to use whenever someone not very familiar with the area needs to travel.
[Answer]
This is really not that much different from flying a small plane over the less-populated parts of the western US, which I've done a number of times. On a clear night, it's quite easy once your eyes have adapted to the dark. On nights with a high overcast heavy enough to block starlight, you really want to be flying on instruments.
On the starry nights, the real problem comes not when the ground is completely dark, but when there's just one or a few ground lights, say an outdoor light at an isolated ranch or mine. You tend to get fixated on that, and can lose orientation. Not a pleasant feeling.
That lack of orientation is the real problem with any sort of flying in limited visibility. You CAN'T depend on your internal senses to report your orientation. You need external info, or instruments and training in how to use them. Look up "VFR flight into instrument conditions". Do that without proper training, and your life expectancy is about 3 minutes.
[Answer]
**[Ley lines.](https://en.wikipedia.org/wiki/Ley_line)**
[](https://i.stack.imgur.com/gL9xV.jpg)
<https://www.manchestersfinest.com/articles/myths-of-manchester-the-ley-lines-that-channel-the-citys-creativity/>
Ley lines are straight, invisible energy channels in and on the Earth. Animals and witches can use them to navigate.
<https://docsbay.net/called-lung-mei-or-dragon-lines-in-china-ley-lines-have-been-known-and-used-by-practitioners>
>
> ...described Ley Lines as “Lines of Power,” known only to Witches (who
> were not portrayed particularly sympathetically) who had handed the
> knowledge of them down from Megalithic times. After this Ley Lines
> were increasingly thought of as being energetic and magical in
> nature..... By the ‘60s Ley Lines were equated with the Dragon Lines
> of Chinese Feng Shui, and perceived as energetic Meridians linking
> Vortices of Earth energy... Ley Lines are thought of as being currents
> of the Earth’s energy: you will often find them described as MAGNETIC
> –this is because in the older sense of the word “Magnetism” was one
> more term for psychic energy. The Earth’s “magnetism” is thought to
> react with the ANIMAL MAGNETISM of living things in a way which is
> unconscious and instinctual. Birds, animals, insects, and bacteria,
> are believed to use Ley Lines as a guide in their migrations across
> great distances, as presumably did early humans....This is also how we
> identify Ley Lines today, through an instinctive reaction manifested
> through clairvoyance or through DOWSING. The point where two or more
> Ley Lines meet is usually the site of an energy Vortex. There are
> thousands of such Vortices, just as the body has thousands of minor
> Chakras. And just as the body has a few highly developed Major Chakras
> some of the Earth’s Vortices are much more developed than others. Ley
> Lines have the same connection to the Earth’s Vortices that Meridians
> have to the body’s Chakras...
>
>
>
Your witches can see or perceive the ley lines - either via innate ability or magic. Many ancient structures are sited on energy vortices and so are easy to find using the lines. Newer structures built by persons affiliated with or advised by witches are also often sited on vortices - in small part because they are easier to find but more importantly because of other benefits such sites provide.
Some things are purposefully as far away from any ley line as they can be.
[Answer]
They can use stars to tell the North, and then the horizon line, recognizable because it gives a sharp separation between starry sky and dark ground, to recognize landmarks which can act as reference points for navigation.
Once they have the reference points, they can memorize each route as a sequence of reference points and times of flight. Time of flight can be memorized in terms of certain standard witch chants, like "Highway to heaven" or "Stairway to Hell".
If the sky is cloudy or foggy they are forced to raise above the clouds and rely on at most mountains as reference, if there are any in the surrounding. If they are flying on the lowlands they are out of luck.
But in that case they can simply break into the hut of a peasant and pull out of him the directions for the closest place.
[Answer]
Depending on how far north (or south, anyway how far from the equator) you go, you don't really get full darkness in summer. I was wild camping in the Scottish highlands recently, and [most of what we'd call nighttime was twilight (example:Inverness)](https://www.timeanddate.com/sun/uk/inverness).
On a cloudy night at Loch Ness, when the moon was obscured, I could see campfires that hadn't been put out several km away across the Loch in the middle of the night. A watchman may well keep a fire or lantern in a town; the person the witch is trying to get to could be told to light something, perhaps in a distinctive pattern (3 fires forming a triangle is a distress signal in our world)
In winter, as I commented, the reflection of starlight on snow or radiation fog (mist in valleys) would also be very helpful. Then of course you have long nights, so you 'd need it.
With experience of a place, you can orient yourself based on information from the faintest of sources of light, far less than you'd need somewhere unfamiliar. I work in research darkrooms where this can be quite apparent. It also struck me today that *audible* cues are important in that situation. Translated to this setting this might mean following a river by the sound of it below, then turning towards the moor where the [nightjars](https://en.wikipedia.org/wiki/Nightjar) call. Being in touch with nature to that extent fits with the context as well. Avoidance of light also fits the need to be dark-adapted.
As I suspected there would be a Discworld reference, and I chanced upon it last night. In *Wintersmith*, Tiffany Aching, while flying on her broomstick, spots the light from an inn, and uses it to find a nearby destination
>
> But now there were lights below, fitful and yellow. It was probably the inn at Twoshirts, an important navigation point. Witches never stayed in inns if they could help it, because in some areas that could be dangerous, and in any case most of them inconveniently required you to pay them money. But Mrs Umbridge, who ran the souvenir shop opposite the inn, had an old barn round the back and was what Miss Tick called FTW, or Friendly To Witches.
>
>
>
[Answer]
I think that flying on broomsticks is highly dangerous, even if done in broad daylight. Enchanting a chair or a wagon or a horse to fly would be much safer.
In recent years I have lived in bedrooms which are almost pitch dark when the lights are out, where all I can see with the lights off is blackness or very, very dark gray. But if I wake up in the middle of the night the gray is much lighter and I can see enough details to walk around.
So I deduce that my eyes become dark adapted whenever I am in the dark for a long period, whether I am awake or asleep, and whether my eylids are open or shut.
So possibly your witches might walk out into a field carrying broooms and wait around, like amateur astronomers wait around, for their eyes to dark adapt. They could put blindfolds on, or lie down, close their eyes, and take short naps, before getting on their brooms and flying away.
Or maybe your witches only travel in nights which have bright moonlight and bright starlight, and so avoid flying on dark nights and crashing into the ground. If people find dead bodies next to broken brooms and signs of crashes, they might suspect that stories about witches flying round on brooms are correct.
[Answer]
Compasses were known in Europe as early as the late 12th century, and a lot earlier in China. Surely witches had the knowledge to create handy devices based on compasses that fit around a broom handle.
Otherwise, with their command of animals, they could train an animal know for its nightly navigation, and carry them in a cage on their broomstick. Perhaps every town has a (secret) outpost where witches can rent/borrow/buy an animal which knows the direction to the next town. They fly from town to town after all.
[Answer]
The natural way for witches to navigate would be magic. You do not want them to be able to see in the dark, but that should be more of an annoyance than a problem. Possible avenues for navigation would be:
* Magic compasses, or other items, which can be either set to the destination itself or to magic landmarks nearby (stone circles, larch forests, etc.)
* Magic moss, animals, etc. which glow in the present of magical makers and landmarks. (You would take with you.) This would allow witches to create "roads" where, if followed, there thingamajig will glow the brightest. (This would also give another explanation why flying in the daylight is not possible, and why flying near cities is different to rural areas.)
* Autopilot spells for the broom. (Which could be made more complicated by the broom always taking the direct path, regardless of what is in the way.)
* Navigation by local magic beings, à la after the fairy colony, fly right, until you see the trolls cave, ...
Bonus:
* Although your witches have normal human sight, you might allow them to create some kind of night vision goggles using their magic.
[Answer]
If bringing a lantern themself won’t due, or if using magical light is out of the question, then you could try to derive a sort of magic radar. It’s magic so you could choose how it works but they could send a magic ping which bounces off solid surfaces and returns to the witch or maybe to the broomstick or a device attached to the broomstick or held by the witch. Radar is invisible to outsiders but very useful at getting a 3D map of the land around you, or seeing other flying objects (like other witches) nearby. You could also do sonar or lidar but idk how well they would work in the witch’s situation
Edit: if you don’t want witches having radar vision or something, and if you don’t want a big tv screen stuck onto the broom sticks, then you could use magic to make a holographic 3D that hovers in front of the tip of the stick, like the maps above the sea glider in subnautica. It could appear or disappear at the witch’s whim. This could make Witch Broom sticks more than just a stick that a witch gives the power to fly if that appeals to you. If witches are some secret society in medieval Europe then there could be secret broom stick shops which sell normal broom sticks for normal people but if the witch shows some pendant or something, they can buy a magical broomstick with the newest radar and whatever magic trinkets you could think of.
[Answer]
>
> The witches may not always personally know the route well, but they can produce their own maps if needed.
>
>
>
This is all those ladies need, really.
It should take a lot of gall, daring and stupidity to go against a witch, no matter what.
>
> A witch ought never to be frightened in the darkest forest, Granny Weatherwax had once told her, because she should be sure in her soul that the most terrifying thing in the forest was her.
>
> -Sir Terry Pratchett
>
>
>
This extends to the skies and to geography:
>
> Granny had been introduced to broomstick flying quite late in life, and after some initial suspicion had taken to it like a bluebottle to an ancient fish-head. A problem, however, was that Granny saw every flight simply as a straight line from A to B and was unable to get alongside the idea that other users of the air might have any rights whatsoever; the flight migration patterns of an entire continent had been changed because of that simple fact. High-speed evolution among local birds had developed a generation that flew on their backs, so that they could keep a watchful eye on the skies... Granny's implicit belief that everything should get out of her way extended to other witches, very tall trees and, on occasion, mountains.
>
> -Sir Terry Pratchett again
>
>
>
If a witch knows which direction to go (which she can find out with a compass, a map, or looking at signposts prior to flying) and the distance, all she needs to do is go. It might be more like a long jump than a flight, really. Makes you think about the origin of the seven league boots.
[Answer]
WWII night bomber pilots used to navigate based on local landmarks, things such as rivers were always reckoned to be good navigation aids because they reflected even slight amounts of ambient light from the stars. This was why cities like London were easy targets, they had rivers running right through them and the reflections were visible for miles even on cloudy nights.
[Answer]
You are perhaps neglecting one of your most potent aids, your various trusty familiars and through them their reliable and extensive networks of kin folklings. Whether cat or bat or through those many other creatures you are linked to a wide flung navigational infrastructure.
Recall from hot air ballooning, that sound travels as well as light and ears are as sensitive as eyes in quiet and gloomy settings (though both are jarred by an errant lightning bolt and its attendant thunders). Other senses may not help as much from on high but a keen nose may trace typical seasonal fragrances, you may well find your way by aeolian ragweed pollen perhaps requiring to suppress a sneeze that importunately gives you away (but use your allergy spells, just like you apply your stinging insect ones - whether incantation, ointment or tincture).
Wikipedia: In European folklore of the medieval and early modern periods, familiars (sometimes referred to as familiar spirits) were believed to be supernatural entities that would assist witches and cunning folk in their practice of magic.
[Answer]
## Checkerboards or arrows
Sort of like the old Kai-Tak approach checkerboards, but placed as needed on hilltops. Use materials which alternately reflect and absorb starlight.
[](https://i.stack.imgur.com/Mt0JS.png)
[Or use "arrows"](https://www.dreamsmithphotos.com/arrow/) although, that might be a bit obvious.
[](https://i.stack.imgur.com/mkBq2.png)
Or possibly, a circle of standing stones might do the trick. Also, centuries later, people would wonder what the heck it was for!
] |
[Question]
[
I just had an idea – likely an absurd one – but it could make an interesting plot.
---
Picture this scenario – Present day earth. (easy to picture) But, there is an antagonist. He has a facility full of powerful air compressors and vacuum pumps. He also has lots of massive (heavily armored) air tanks, to store the air. He then begins depleting the atmosphere. He threatens all major world governments (and anyone with enough money to be worth it) that he will completely deplete the atmosphere and kill all life on earth unless an absurdly high ransom is met. If it is met, he will release the air again, replenishing the atmosphere.
However, the protagonist organizes a team, infiltrates the facility, damages the already highly pressurized containment tanks, and plants explosives near the damaged parts. They escape far enough away, and detonate the charges. The tanks explode violently, releasing all the air back into the atmosphere.
For um... *reasons* the various world powers can't just attack the facility directly.
---
The atmosphere obviously contains an absurd amount of gas - it is really, really huge. The antagonist only needs to deplete a small portion of the atmosphere - just enough so there is a difference in its density noticeable enough to scientists so that the antagonist's threat of total depletion seems valid.
My question is, how (without hand waving) is it remotely possible for the atmosphere to be even partially depleted, pressurized, and then contained on any number of containment systems on the earth's surface? Specifically, how big of a storage system would be needed to make a noticeable difference in the atmosphere's density? (assume you can use any material currently known to make the air cylinders - no unubtanium bottles that can hold a few trillion PSI.)
[Answer]
The total mass of the earth's atmosphere (courtesy Wikipedia) is 5 × 1018 kg. The most common atmospheric measure is air pressure, which varies around 5% through natural weather cycles, and up to 10% in extreme hurricanes. But we'll pretend that all the scientists are cooperating in this and can detect a global decrease in atmospheric pressure of 1%
So your evil madman would need to store at least 5 × 1016 kg. For simplicity, let's just pretend the atmosphere is all nitrogen. At standard temperature and pressure, nitrogen masses 1.2 $\frac{\text{kg}}{\text{m}^{3}}$ - but if we choose to liquify it, we'd increase that to 800 $\frac{\text{kg}}{\text{m}^{3}}$.
So the evil madman needs 5 × 1016 kg of liquid nitrogen, which would occupy 6 × 1013 m3. The largest oil tankers have a volume of 300,000 m3.
So build 200,000,000 ultra-large oil tankers, install insulated and reinforced tanks to hold the liquid nitrogen, and then somehow find enough electricity to run the refrigeration systems to liquefy the gas, and keep it liquid.
If instead you go with tanks and unobtanium, the critical point of nitrogen occurs at about 73 atmospheres of pressure, after which point it's either a liquid or a supercritical fluid. I haven't done the math beyond that point, but liquefying it seems to be a better option for density.
Bottom line, your evil madman could do a lot more with his nearly-inexhaustible energy source directly, rather than blackmailing us all with atmospheric depletion.
[Answer]
Other answers focus on how impractical it is to steal the entire atmosphere, with the lone exception of [Mega Maid](https://i.stack.imgur.com/F9Doy.jpg) (since Spaceballs is 100% scientifically accurate). But I just had an idea for how you could still have your villain demand a ransom for stealing the atmosphere, trap significantly less than the entire volume of the atmosphere, and if you are looking for conflict, in such a way that some people view them as a hero.
With [global temperatures higher now than most of human history](https://xkcd.com/1732/), due mainly to CO2, you could have the villain take all the excess CO2 out of the atmosphere, and then ransom the world governments to not release it back once the world sees how much more stable the climate is without the extra heat, and glaciers start reforming, traditionally frozen parts of the world stop thawing, reefs stop dying due to acidification, etc. [This source estimates 2.996×1012 tonnes of CO2](https://micpohling.wordpress.com/2007/03/30/math-how-much-co2-by-weight-in-the-atmosphere/) in the atmosphere, [significantly less than the Oxygen and Nitrogen that is needed for survival](https://en.wikipedia.org/wiki/Atmosphere_of_Earth#/media/File:Atmosphere_gas_proportions.svg). This requires them to store significantly less than taking the Oxygen away, for example, but still take a meaningful enough part to get peoples attention. The amount that would need to be stored is still gigantic in volume, but much more practical than the other plans here.
They could always then use their technology and storage facilities to open a legitimate business removing CO2 from the air too.
[Answer]
1% of atmospheric pressure would be about $10 \frac{g}{cm^2}$over the Earth's surface. At $0.87\frac{g}{cm^3}$ That would be enough liquid atmosphere to cover the entire Earth's surface to a depth of 11.5 cm.
How much energy would it take to compress that much of the Earth's atmosphere? I found a calculator and the just using the compression formula I ended up with $142,630 J$ to compress $1 m^3$ of atmosphere into $0.001408 m^3$ which is what the liquid would take up. For 1% of the Earth's atmosphere that comes to $6\mathrm{e}{21}J$ or $1.6\mathrm{e}{15} kWh$.
Humanity's average energy consumption is [18 Terawatts](https://en.wikipedia.org/wiki/World_energy_consumption) or $1.8\mathrm{e}{10}kW$. So your villain would need 90,600 hours or 10 years of using as much energy as all the rest of humanity combined in order by compress 1% of the Earth's atmosphere. Electricity consumption only averages 2.1TW, so if you use that number it would be more like 90 years.
[Answer]
The amount that would need to be removed from the atmosphere before it caused a drop in pressure large enough to be noticed against the constant changes in localized pressure systems would be incredibly large. The containment system could not be stored in a fortified compound, but would completely cover the landscape of a good sized country.
One additional problem would be any drop in atmospheric pressure would result in water vaporizing from the ocean, bumping its pressure back up.
[Answer]
As with many ambitious plans, there's really only one way to do it: [Distribute the work-load.](https://en.wikipedia.org/wiki/Great_Oxygenation_Event)
For those who don't click links, the "Great Oxygenation Event" happened about 2.3 billion years ago. Cyanobacteria started photosynthesizing, which produces oxygen, and rapidly raised the O2 levels in the atmosphere from "negligible" to "deadly to most life at the time", causing a mass-extinction event. This new burst of oxygen also started binding with atmospheric methane (a greenhouse gas) and caused the longest snowball Earth period.
As with several other answers, we're not actually going to lower atmospheric pressure. Instead, we're going to change the chemical balance of the atmosphere so that a *particular* element, necessary for human life, becomes much lower in concentration. That element, of course, is oxygen.
Basically, what we want is the reverse of the Great Oxygenation Event. A Great Deoxygenation Event. You'll need some kind of life form (or self-replicating machine, or combination of the two) that takes atmospheric oxygen and converts it into CO2. CO2 is the obvious choice, because it's already the output of the basic animal respiration cycle *and also* is a typical output of many non-biological reactions with O2.
Bonus points of this creature destroys vast amounts of plant life (reducing the ability of the planet to turn CO2 back into O2), *particularly* old growth forests and jungles. If this life form also takes advantage of non-biological processes to convert O2 into CO2, all the better.
As CO2 levels in the atmosphere increase, the global temperature of the Earth will also increase. Scientists estimate that the "no turning back" point is 2 degrees Celsius. So if you can raise the global average temperature by 1.9 degrees Celsius, people are going to be losing their minds. They'll probably pay you anything to start reversing the process.
The trick is... finding a way to take "credit" for this, given that I just described the human race. Also, getting people to believe it's really happening, given that many of them don't.
[Answer]
As others have noted, tanks of liquid air are impractically bulky. We can, however, solve this bulk problem. Just compress harder.
The density of neutronium is about 10^18 kg per m^3, so we could store the entire Earth's atmosphere in a mere 5 cubic meters of pure neutronium.
You'd have to maintain high pressure, and have a confinement system that generates sufficient radiation and other effects to regenerate the neutronium as it decays.
While the pressure required to contain the neutronium is higher than one can practically achieve, it is the radiation pressure that going to be more difficult to deal with.
Neutronium has a half life of 10 minutes. In a neutron star, this decay is effectively prevented by the radiation and physical pressure.
We'll estimate that the amount of radiation you'd have to bathe the neutronium in is roughly equivalent to its decay. In the case of neutrons, 0.08% decays into energy every 10 minutes.
At 5E18 kg, 0.08% every 10 minutes is 4E15 kg of energy every 10 minutes, or 7E12 kg every second, or 6E29 Watts.
The sun puts out 4E26 Watts. So the scientist will have to first develop a K-Type 2.3 civilization and devote it entirely to this experiment.
On the down side, if the scientist where to release containment, the gravitational binding energy of Earth is E32, which is roughly the energy released as the neutronium decays. So the promise to release the atmosphere if paid may not be as strong an incentive as the scientist hoped.
Now, if only a fraction of the Earth's atmosphere where converted to neutronium, the above equations would be off by a few orders of magnitude. So the Earth would no longer be disassembled into debris by releasing it; instead something a bit less extreme, like something the size of the moon might be broken off it.
[Answer]
Consistent with the analysis by others to reduce the atmosphere by 1% it would be about 63,816,604,708,798 cubic meters of liquid nitrogen.
That is 10 km high the size of Texas.
You can compress about 10% more to solid but not clear you can do that at standard temperature.
You could take 10% of the oxygen with 72,842,998,585,573 cubic meters. Which is a much bigger threat as 30% would life threatening.
[Answer]
Just a tiny bit of handwavium...
Make sure that your civilization/antagonist has proper technological advancement. Somehow make them able to either transport black hole, or create a wormhole leading to it. Both aren't realistic, but this isn't [hard-science](/questions/tagged/hard-science "show questions tagged 'hard-science'").
Congratulations. You've compressed the entire atmosphere to the mathematical point.
[Answer]
# Use natural bottles for critical parts of the atmosphere
Existing answers already mentioned that volume would be a problem if one were to take out the atmosphere in general. The solution for this would be to find the rarest element that is needed to sustain life (anything important rarer than oxigen?!) and only store this.
In addition it was mentioned that people might notice a tanker park the size of a large country. The solution to this seems to be to use the 'natural bottles' that the world has available. There are huge reserves of oil and gas, and therefore the obvious place to store large volumes is not in a huge tanker park, but to put it in (empty?) reserves somewhere underground.
I did not run the numbers (and I don't think it will work out), but I would say this is the closest you could get to a realistic scenario.
] |
[Question]
[
Here on the Space Station 'A long way from anywhere V' (not to be confused with [any other](https://en.wikipedia.org/wiki/Babylon_5) [space stations](https://en.wikipedia.org/wiki/Star_Trek:_Deep_Space_Nine)) a wide variety of species pass through on their way to the Krasnikov tube terminal. Even the starship ['Exciting Undertaking'](https://worldbuilding.stackexchange.com/questions/63587/why-are-there-no-toilets-on-the-starship-exciting-undertaking) stops here from time to time. Due to the number of strikes on the Nebula Line they often find themselves onboard for long periods of time and don't want to wear rebreathers constantly while still wanting to enjoy the company of other species.
We have all sorts here, aquatic creatures, high gravity sulphur breathers, low gravity plant men, humans and even some kind of [sentient slime mold](https://xkcd.com/877/). Our Generic Transliterator deals with language issues and all staff receive extensive lectures on the dangers of 'improving interspecies relations', but there are still a few issues to work out.
The biggest question is how can so many species meet, trade, socialise and queue to shout at the Complaints division of the Krasnikov Tube Corporation without suffocating, being crushed to death or accidentally combusting upon contact with the Magma Men of Plodial 4?
To be clear: What I'm looking for here is the mechanism by which so many species with different environmental needs can live on the station without needing to wear exoskeletons/environment suits constantly.
[Answer]
Many differences are quite easy to overcome. Moderate- and high-gravity-worlders, for instance, can live in a mid-to-low-gravity environment without much trouble, at least for a little while. Plant-men, humans, and slime-molds can share the same atmosphere. Stationary or slow creatures can use hover-lifts to get around. Even some normally-aquatic creatures may be able to get out-and-about, as long as the air is humid.
For those that require (or merely demand) full immersion in liquid, broiling temperatures, caustic air, or otherwise extreme environments, however, nothing short of a full environment suit will do... *most* places. Luckily, the motto of Space Station V is, *This Place is Nice 'Cause We Built It Twice.*
The motto, of course, is untrue. The station was actually built a dozen times, with more on the way; each replica holds the lowest common denominator for the comfortable survival of the maximum number of races. One station is full of water, another hundreds of degrees hotter, and still another filled with caustic air. However, each station is otherwise a perfect duplicate of the original... visually, anyway. The stations beam fully interactive holograms to the others; that way, a magma man can shake hands with a (holographic) water-dweller, and a low-gravity-worlder can carry on a cheerful conversation with a high-gravity-worlder. Ships are automatically routed; where required, transport ships carry passengers to the correct stations.
Shops, too, are duplicated between stations, though for a few shops that is simply not possible. Water-dwellers, for instance, are disgusted by the idea of ice cream, and the asbestos-laden magma-man clothing store has little relevance to humans. In those cases, the shops in other locations are only painted store-fronts; while you can look inside and see a magmom buying a cute asbestos solar-flare-hat for her hot daughter, you're looking "through" an otherwise blank wall. The room inside is used for maintenance or storage. Some stores compromise with alternate or holographic wares; or, on the flip side, high-traffic locations are "double-mapped", allowing increased seating without wasting space seating holograms, yet still allowing a merman to wave to his slime mold buddy.
As an added benefit, computer-generated holograms can fill a variety of roles, from a basic prerecorded shopping hologram to make shops seem busier than they may actually be, to visually replacing high-dollar items, so shops can look full without stocking useless items. Renting a basic information hologram is much cheaper than hiring and training a real person, and cuts down on the minimum-wage retail-worker drama. Blank walls can be filled with holographic panoramas, making the compressed space of a station feel much larger, while ever-changing scenery alleviates the boredom of what is essentially a modern version of those old airports.
[Answer]
Space travel was a nightmare of constant encounter suits and multiple stations sharing orbits until there was a big collision between two stations in unstable orbits around Life in Exile 5. After that it was just constant encounter suits. Luckily the airtight nature of the suits meant that the fact nobody had washed in 6 months didn't affect other travellers.
Everyone who needed a special atmosphere either had to build their own station or sleep in a space suit for months on end. That was until the first modular starship was built.
The concept of the modular starship was a breakthrough in multi-species transportation. It was a corridor with standard docking points an engine and a bridge. Nothing more.
Each species wishing to travel would provide a habitation module on a standard external design with an evacuating airlock which could attach to the docking point either on the ship or on the space stations. If they wished to transfer to another ship they could just detach from the ship and dock with the station until their next ride arrived.
Encounter suits are still required in communal areas and if you live in an atmosphere hostile to other species it's terribly bad manners to allow your environment to leak into these areas. Though some of the more jury rigged frontier stations it's not unusual to have communal areas either hostile to all due to mixed environments or entirely evacuated to vacuum either intentionally to suppress corrosive atmospheres or just through bad maintenance.
If visiting frontier stations we advise wearing your encounter suit at all times while out of your pod, even if the station is advertised as being suitable to your species.
[Answer]
They use 'The Matrix'.
When it comes to public space travel amongst widely varying species, it's very tricky to keep everyone alive with such differing requirements. So where there's going to be a big mix of requirements, they borrow from the ideas of intermodal freight transport.
At every space port, there is a large stock of life-support containers, of a number of standard sizes to fit all life forms - each able to create a wide variety of environments for the lifeform inside (and perhaps some specialist containers for *really* odd species). These can then simply be loaded nice and neatly on to the ship for travel. Where the passengers will mostly be of one species, then the ship would be split between normal passenger travel and a 'cargo' hold for the boxes. Because the boxes are intermodal, there's no need to get out until you reach your destination - boxes can be swapped between connecting flights and stored where there is a gap between flights.
These boxes also contain 'The Matrix' (I just came up with that name, don't know why) - a virtual reality system that enables everyone to socialise on board the transports. The communal areas can now of course be as large and luxurious as you like!
[Answer]
Fortunately, the OHSA reforms of 2173 C.E. (Convenient Era) introduced total immunity for spacecraft and space station operators for loss of life or property as a result of energy wall malfunction.
Thanks to these well-though-out reforms, prisoners may be kept in cells locked with energy walls that require constant power to keep them in, hull sections can be replaced with large, breathtaking windows that that only occasionally empty the room, and, more importantly, both common crew and high-profile ambassadorial staff can move around the station in a comfortable bubble filled with their desired atmosphere.
The station's translocators will occasionally replace some of the fluid inside the sealed environment, ensuring that it remains breathable and safe at all times\*.
\*In the event of that the translocators are [preoccupied with sanitary tasks](https://worldbuilding.stackexchange.com/questions/63587/why-are-there-no-toilets-on-the-starship-exciting-undertaking) during an outbreak of andromedan cholera, priority will be given to high-profile ambassadorial staff. Other visitors may rest assured that the station computer will serve them in order of priority and they will be able to resume normal breathing Real Soon.
[Answer]
Interaction between "environmentally incompatible" species was a big problem, until the generic atmosphere system was invented.
This system consists of nano-robots (I'll call them nano-riders) and generic-gas.
Every creature is coated in nano-riders, that are invisible to the naked eye.
**The nano-riders** basically emulate enviromnental conditions directly **on the skin** by taking everything they need from the atmosphere.
**The atmosphere** in turn, consists of the normal atmosphere of the planet, plus clouds of nanorobots that are generating "generic gas" from the molecules of the planet.
**Generic gas** consists of passive-non-reactive compounds that contain all the molecules that can possibly be needed by the nano-riders, no matter which host they "ride".
Nano riders are keeping their numbers up by self-replication, have limited intelligence to prevent grey goo scenarios and will repel foreign riders (so shaking hands between a magma man and a aquatic beast is not an issue anymore).
They come in a number of variants and one host carries all the variants needed for his enviroment and repel elements and molecules that could harm the host.
Their variants include, nano-gravity generators, molecular manipulators, replicators, and heat manipulators.
The fuel that is needed by the machines is also taken from generic gas.
All planets that signed the GAET (generic atmosphere enabeling treaty) have this system installed.
[Answer]
The Matrix idea is by far the best. However...
## Hook up their ship's life support to standard residential blocks
Per Coalition Guideline #87923, section 7, all ships planning to dock with Coalition space stations are recommended to carry standard 273-pin life support interface connections that meet or exceed Guideline Specification #28447. This equipment will allow your ship to connect to an Astralsquadron-standard Reconfigurable Station Environment, and provide the same environmental conditions you enjoy aboard your ship within your station quarters.
Using your own ship to provide the life support in your A.R.S.E. ensures that you can enjoy comfortable living conditions during your time on the station.
All A.R.S.E.s are equipped to move independently around the station, allowing meetings between vastly different species to take place in comfort, simply by pressing their A.R.S.E.s together.
[Answer]
# Self-selection
The Universe contains a very large number of sapient species. But not all of them come to Space Station 'A long way from anywhere V'.
The Magma Men of Plodial 4 know that they would freeze solid if they tried to visit, so they stay away.
The Methane Breathers of Blubliblub know they would catch fire in an oxygen-rich atmosphere, so they stay away.
The Kiniggits of Galia know they would be poisoned by all the water vapor in the air, so they stay away.
And so on.
What you are left with is just those species that are water-based and
oxygen-breathing, thriving at approximately the same temperature. Fortunately that is still a good number of species.
The Methane Breathers of Blubliblub and other places have their own stations where they meet only other methane breathers. The Kiniggits stay on their ships, and the Magma Men really doesn't travel much... Life support is *such* a hassle at 900 degrees centigrade.
[Answer]
## On *unique needs*
While species from different worlds will obviously live under different pressures, at different temperatures, and in different material, there aren't so many combinations out there.
>
> ### Almost all planetary atmospheres are combinations of:
>
>
> * **Hydrogen**
> * **Helium**
> * **Oxygen**
> * Neon
> * Nitrogen
> * Carbon
> * Water
>
>
> ### And most ocean-dwellers will live in:
>
>
> * Water
> * Methane / hydrocarbons
> * Ammonia
>
>
>
**This isn't all that diverse,** as most of these creatures will be able to breathe to some extent in a reduced number of environments without harmful reactions occurring. You can lump humans in with most nitrogen breathers, and almost all aquatic species will rely on fresh water; sharing may reduce space taken significantly.
It is important to note that other compounds may be mixed in - for example, a saltwater species will not survive in freshwater, and an oxygen-breather won't enjoy carbon monoxide - so that should be factored in to your environments.
Finally, there may be unique cases out there. For these individuals, you are welcome to have separate rooms / systems rigged with pumps; you can simulate the environment they need.
### In short, it's not that hard to build rooms for most species.
---
## However
Consider that most species' ships will already have environments tailored to them, and that individual organisms will come prepared to travel through the environments of both their previous and their destination planets.
This means that they **will** carry breathing apparatus, and most likely temperature and pressure suits as well.
It's not so much of an inconvenience to keep them together in one environment when that's the norm, and they came prepared.
[Answer]
**Space Station V** has a mandate to ensure the survival and moderate levels of comfort for all species routed through its facilities.
A limited number of self-contained hermetically sealed environments are provided for the comfort of transit passengers using the most common atmospheres.
In the unfortunate event of death or irretrievable loss of dignity, reasonable compensation will be paid to any family/herd members. Registration should be made by filling in a form at this web site - [Reporting a Death](http://www.startrek.com/DS9/reporting_a_death)
If there are any questions, please use the [Live Chat](http://www.startrek.com/DS9/speak_to_a_customer_support_goon)
] |
[Question]
[
This a follow up on the previous post that asked how strong graphene armor would be and the general conclusion is that we have no idea sadly. So in this post I will ask a more relevant question.
If we have made armor with advanced, light-weight carbon and ceramic based materials that can easily stop most bullets like 9mm and 5.56mm calibers that are used in military's and cover the majority of the human body. How does this affect infantry warfare and more specifically guns?
Will guns need to get bigger and stronger to compete, or something else entirely?
And for those who will point out that modern militaries do not cover the entirety of their soldier's body in armor due to weight, heat and comfort issues: Let's just say that the same advancements that made the armor in the first place also allowed the creation of cooling load bearing systems that are simple and rugged enough to be used in the field.
EDIT: I fixed the question and want to clarify on the "entirety" part: What I meant to say was that the soldier has more armor on person than modern militaries to protect the extremities, which is allowed by the lightweight nature of the carbon materials, the cooling capacities and 'minimal; load bearing systems. Meaning that there are gaps in the armour, albeit covered in a cloth that has carbon materials like CNT.
Sorry for any confusion.
[Answer]
If armour cannot be pierced, then you use weapons that don't rely on piercing.
One option that has been mentioned is thermal attack. Use fire. Napalm, phosphorous, thermite; all kinds of incendiary weapons you can think of. There's a person inside that armour, and they need to stay cool. Make the space around the armour hot enough, and the armour will have nowhere to shed heat, and the person will be forced to retreat, or cook. One advantage of this approach is that there's not all that much need to aim, unless the armoured individual is airborne. You can cover a whole area and get a good firestorm going, and it will act as an impenetrable barrier to enemy troops, and a death sentence to any already in that area. Downsides of this approach are mostly the flipside of this not needing to aim: it's a pretty widespread and indiscriminate assault; not really usable defensively because you risk incinerating whatever you're defending. It can also take time; if the armour is well insulated then it can take way too long before the enemy is out of action, giving them time to escape, or deploy weapons of their own.
There is a simpler approach, though, and for this we look to history. Specifically, the time period after good plate armour became available, but before the development of bodkin arrows and powerful crossbows. When faced with armour that cannot be pierced, you switch to blunt kinetic attack. In other words, [it's hammer time](https://en.wikipedia.org/wiki/War_hammer).
Just because the armour stops a round from piercing, that doesn't mean the round is harmless. That kinetic energy has to go somewhere. If you fire heavy enough rounds at high enough velocities then each one is going to hit the enemy like a kick from a horse. This means using things like high-calibre rifles, and/or belt-fed automatics in high calibres, possibly even gatling-style weapons. Even if the armour holds its shape perfectly, the impacts will transfer kinetic energy to it, and from there to the person inside. A number of hits will ricochet off, but those that hit flat will be hammer blows, and the person inside the armour will bounce around in it, resulting in bruises, broken bones, and internal bleeding. The only ways to combat this is to make the armour heavier (to increase its momentum) and/or larger (to give more space for internal padding and shock absorption), both of which make the armour more cumbersome and less useful.
Other than that, you can challenge the "cannot be pierced" property of the armour somewhat. It may be largely invulnerable to regular bullets, but there are other ways to puncture armour. Technology from anti-tank rounds might find their way into smaller munitions (iirc there are currently provisions against exploding rounds in various international treaties, but the same goes for various other things that are still used, either by loopholes, legal technicalities, or just by ignoring the treaty entirely). The US military has developed [rifle-sized weapons that fire miniaturised shells](https://en.wikipedia.org/wiki/XM25_CDTE). These are mostly used for airburst rounds that defeat hard cover, but if bulletproof armour became commonplace then I'd expect to see these loaded with [shaped-charge](https://en.wikipedia.org/wiki/High-explosive_anti-tank_warhead) rounds to punch holes in the armour.
[Answer]
In general:
* Strong armor/weak ranged weapons means **more close (up to hand-to-hand) combat**, shorter and more active battles, elite troops rules battlefield (less camo, but more colors and honor), relativly less casulties in battles (defeated prefer to run). It also means that **charge is stronger than equal number and quality defence**
* Strong ranged weapons/weak armor (like it is now) means less to no close combat, long (days) "hide-and-seek" battles, with a lot of sittig in trenches and covers, more total casulties (it is useless to run from artilery or bombardmends), constant stalemates (due to defence is times stronger than attack).
(had to mention - there are a lot of "transition states" between this two; more of this - less of that)
Particular in your case guns would become short-ranged but more powerfull. 20+ mm handguns (handcannons?) with explosive (commulative) load and with effective maximum range about 100-200 m (they had to be short to keep it weight low) would become practical.
If you think of bolters and marines from WH40K - you would be wrong. But there would be a lot of parallels. Elite heavy-armored troops with bolter-like cannons to fight each other on close range (*may be* with hand-to-hand weapons), and lot of "infantry" - no-armored, but heavy-armed with large "antitank" rifles to fight those troops from long range (but totaly useless at middle and close range).
War machines would remian almost the same (just less lowcaliber machinguns) - they are already capable to fight heavyarmored troops.
[Answer]
**Napalm Grenades**
In reality, you're trying to describe an 'Iron Man' style suit for your soldiers and while that may one day be possible, it's not practical - that is to say, that kind of protection would cost more than I suspect most militaries would be prepared to pay, but I digress.
What the Iron Man comics, Movies et al don't really show is that in order for him to be agile enough to be an effective combatant in the field, his suit needs lots of joints, vents, and other areas where the armour seal becomes less than perfect because he has to move his arms and legs vigourously as he fights. The seal may well still be airtight, but that would be due to rubber, silicone or some other flexible sealing gasket material that moves and shapes itself to the joints as he works.
The practical upshot of this is that if you really want to get Iron Man, and he can't fly, you don't need to get through the armour, you need to get through the weakest points, namely those flexible seals.
So; napalm grenade. Super hot sticky incendiary 'syrup' that sticks to the suit and drips into those seals. Your soldier gets it in the neck, the shoulders, the elbows, the hands, the groin (!), the knees, and the feet. You may not even kill him, but you're going to render him combat ineffective.
Ultimately, these kinds of incendiary weapons can even evolve to be delivered via long range mechanisms as well. Imagine (if you will) a large calibre weapon (like a 50 cal) that has shells that deliver an ignited payload of napalm that splash against the armour and stick there, to drip down into the seals. Even napalm variants of RPGs and the like. Better yet, you just refit your A-10s to drop massive payloads of napalm bombs over a field to get your armoured soldiers.
Ultimately I think that bullets will still have their place and in modern asymmetric warfare strategies, you're not really sending off soldiers against soldiers; your snipers have more of a workload and they're not targeting the kind of people who wear iron suits. So, bullets may evolve but they would also move to a more specialist role than perhaps they currently fill.
But, when you get right down to it, a soldier who is perfectly protected by modern carbon / ceramic armour has a combat capability close to that of a statue; anything that can move has weaknesses somewhere, and in the case you describe the weakness is best exploited by weapons that stick and burn as they drip over you, and that means that we might see a resurgence in things like napalm to neutralise your armoured soldiers.
[Answer]
**Different types of ammo and weapons**
[Bolo gun](https://www.youtube.com/watch?v=0yEYRxASpzw)
[Taser Shotgun Shells](https://electronics.howstuffworks.com/gadgets/other-gadgets/taser-shotgun-shell.htm)
[Sonic weapons](https://en.wikipedia.org/wiki/Sonic_weapon)
[Chemical weapons](https://www.wired.com/2007/08/psycho-paintb-1/)
[Laser Blinding Weapons](https://en.wikipedia.org/wiki/Dazzler_(weapon))
Basically you can protect from one type of weapon or even multiple types of weapons but you can't protect from every type of weapon. If bullets fail to work, someone will make a new type of bullet at does or switch to a different type of weapon.
[Answer]
As armour improved in the medieval ages, full plate armour couldn't be penetrated except through the cracks.
The 4 methods that jump to mind that were used to resolve this are:
1. Get up close with a dagger and place it through the joints or eye slits.
2. Get up close with a mace or other bludgeoning weapon, and use the fact that the armour can only prevent the weapon going through. All the force imparted from the weapon however still will be largely absorbed by the person inside. A good strike to the helmet will still break the persons neck.
3. flank them; most armour will be best on the front. By attacking from the sides or behind with ranged or melee then you can bypass most of the armour.
4. pick the terrain. Armour, by its very nature, leaves the wearer less manoeuvrable. Selecting an area that is thick with mud, the difference becomes more marked.
Obviously in many battles, a combination of all 4 were applied; with 1;3;4 being used by the generally more agile and less well armoured troops; and #2 being used more by the well armoured troops.
The modern equivalent of #2 would be to use a very high calibre weapon. A cannon ball, if it hit you, has enough momentum that even if it doesn't go through your armour, you're dead.
[Answer]
Modern weapons are more energetic than chemical bonds are. Graphine is no exception.
A Newtonian Penetrator (if the energy levels are low enough that "solid" still matters) or a Fluid Penetrator (if not) model is how deep a given weapon penetrates armor, and it really doesn't care about chemical bonds. It cares about density and thickness.
Modern anti-tank weapons fire high-density narrow jets to penetrate the target's high-density angled (to increase depth) plates.
It is far easier to make a really long, narrow penetrating weapon than it is to cover every inch of something with a thick layer of dense armor. So armor has lost.
Since WW1, static fortifications have lost. Having ridiculously thick armor (in the form of Earthworks, trenches, etc) still gets overrun by mass artillery or other "bunker busting" technology.
Basically, in order to stop a 1 inch long bullet, you need more than 1 inch of the same density material in the bullet *all over your body*. And if you can carry that much armor due to "power armor", you could just carry a heavier gun that fires longer bullets.
Worse, anti-tank missiles mean you can fire a weapon whose "bullet" is longer than the weapon itself.
Non-chemistry based defences could pull off defence beating offence again: Bullets shooting bullets out of the air, force fields that aren't chemistry based, and other relatively implausible technologies.
As a plausible variant of "bullets shooting bullets", warfare where you have swarms of various scale drones. The goal is to *spot* your foe, at which point sufficient ordinance is used to destroy them. Offence becomes a matter of gaining LOS with your drones; defence is getting LOS on their drones before they get LOS on your target. Everyone is using high-accuracy payloads that disable targets trivially, with smaller amounts of high-penetration payloads to nullify "just send a tank" options.
But this looks nothing at all like soldiers walking around in super high-tech plate armor.
[Answer]
# Retrain for headshots
Nowadays, marksmen are trained to aim for center-of-mass, but your advanced armor would apparently make that strategy no longer viable. So you'd have to train your soldiers to aim for the head. It's a smaller target (which is why we don't train people to aim for it today), but it's also the hardest part to protect, since people need to be able to see, and materials which are both bulletproof and transparent are much harder to produce. (Even bulletproof glass would still be vulnerable to headshots, because even if the bullet doesn't penetrate, it does impart significant force to the head, which can still kill just by neck injury, and at the very least it would cause visibility issues for the victim.
As an alternative, you could train to aim for other weak points in the armor, mostly centered around the joints. Joints strong enough to stop bullets are going to seriously hinder freedom of movement, so you may have to sacrifice protection in some areas in favor of agility, leaving some vulnerable areas if you know what to aim for.
[Answer]
In the highly scientific documentary "John Wick 3" we can observe that armor which doesn't allow for penetration, doesn't magically negate the impact a bullet has. A bullet has a tremendous amount of force behind it and can break bones even when stopped. While smaller bullets are often focused on penetrating, larger bullets from 9mm and above have the same force as a hammer. If push comes to shove the switch would just be made to explosive weapons since those posses the largest amount of kinetic force, or 50 cal's would suddenly become as popular as in Call of Duty.
Even if armor magically had the ability to stop kinetic force, this would mean that close quarters weapons would be rendered useless as well since those are all based on kinetic force too. Anything that works from a small distance can currently be done from a large distance.
[Answer]
Assuming all else is more or less equal, that the research really has surpassed weapons fire so these suits are given to everybody instead of the "only select people get this for some reason" and we dont have sudden radiation guns and the Geneva conventions are still in effect. I am also assuming a combination of spidersilks and metamaterials like high CNT substances draped over a framework to add more stopping distance and spread the force over a larger area. This also has the benefit of not really having weak joints as the spidersilks can be draped over them like cloth without impeding movement. the most logical changes are:
* larger caliber weapons, often semi-auto to conserve accuracy. This for the extra kinetic energy to break the bones beneath the armor. This also means less ammo, more recoil and more time between shots.
* as consequence of the above point, soldiers are more likely to survive. Adrenalin during such events often mean that broken ribs, arms and legs can be dealt with reasonably well for a limited time, allowing soldiers to escape or harm their attackers right back.
* as another consequence of the first point, large caliber crew-served weapons would be used more often for automatic firepower.
* less reliance on grenades and shrapnel ordnance. Most artillery and grenades are lethal because of the shrapnel that pierces organs rather than their concussive force (unless it detonates right next to you). Artillery inaccuracy means that it becomes a lot more expensive to try and artillery infantry to death. As a supressive weapon it would still work though.
* more reliance on psychology to win. The British apparently tested things like firing one artillery shot/salvo per minute instead of a constant barrage, and soldiers being shot at would have the opportunity to flee inbetween. This meant that area's could be taken without killing many people as they would just have left. This would also extent to fighting techniques like using noisemakers in combat and just looking fierce.
* humans dont really want to kill one another, this causes the "look busy" actions that soldiers will adopt by shooting in the air above the enemy, packing and repacking their gear (during fights), looking after wounded friendlies even if it is just a scrape etc. With armor this tough it could be that fights become a lot more accurate as the chance of actually killing someone is much lower.
I actually think that specialty ammunition like chemical bullets, bolo's etc wouldnt be used much due to geneva conventions, higher cost and higher chance of weapons failure. Also consider that war isnt about killing your opponent but about making your opponent stop fighting. Anti personell mines are designed to maim the target rather than kill to put pressure on the logistical chain of the enemy. And here you have warfare where shooting your enemy means they have more people to drag off the battlefield alive and care for? Not only will many soldiers gladly take the chance to drag a friendly out of harms way and be out of the fighting themselves it will be much safer for most people involved including civilians as stray bullets will be less of a problem!
[Answer]
Thus you begin the race for effective Energy Weapons.
In the mean time, you want to defeat the common rounds of the day If the Armor tech is good against 5.56 rifle and 9mm handgun it may be good enough for the most common rounds of right now. Here is the problem, there are plenty of more powerful rounds out there.
Consider it as a race of armor vs. energy. A 5.56 Nato round is a lightweight bullet that moves very fast. The Relevant equation is *ke = 1/2 mass times velocity squared* This is also partially augmented by the size of the impact area. Theres lots of nuance there, but lets start with the simple physics. Lets get down to some basic stats. A 5.56 round has a 62 grain (unit of weight) slug that moves at over 3000 feet per second. I don't know all the conversions but if we just call them units it will illustrate the point. 5.56 round gives you (.5 x 62) x 3000^2 which is 279,000,000 units. A 9mm has a heavier slug, but it moves more slowly. 115 grain at 1300 feet per second so 97,175,000 units. Now lets look at the bullet that won WW2. The M1 shot a 174 grain at 2675 fps. That is 615,383,750 units. Well over twice the energy of a 5.56. Escalate it up to something like a .338 Lapua and you get something like 1,134,000,000 units. a .50 BMG gives you 2,907,000,000 units. So you get to decide how well your armor will hold against larger and faster rounds. If your armor is good to stop up to the good ol M1, it will be defeated by the .338 and the .50 will make a mess of your guy. All of the ones I mentioned are rounds and rifles you can buy today. All can be handled by a person, though the last is usually recommended to be shot using a bi-pod.
So what you are going to see is an escalation, fairly quickly, between how good can your armor be and opposing forces deploying larger and larger rounds in the field. You can expect an increase in sniper activity as well. Those larger rounds are easily good to hit targets well over 1000 meters away. Snipers will get a little closer and go for joints and weak spots. Melee weapons will also make a brief comeback. Probably in the world of the Mace and the war hammer.
Another thing you will see very quickly is a variety of armor piercing rounds. It is much easier to change the bullet rather than changing the gun. Regular full metal jackets will likely be replaced by steel core type rounds. Not perfect, but you maintain muzzle energy without deformation on impact and a good shot puts all of that energy on a small, very hard point. In addition, Graphene burns at a fairly low temperature. That means that Phosphorous rounds will likely become much more common. Phosphorous is already widely used as 'Tracers' to help direct automatic weapons fire, often at a rate of 1 out of five rounds being a tracer. Change that to 1 in 2 and then begin making tracer bullets available for all small arms. Tracer impacts the armor and begins burning. next round hits very nearby and the bonds that hold the graphene together start failing. Very bad for the squishy bits underneath.
In the mean time, mad scientists are going to cook up all kinds of nastiness. Gasses, acids, Thermobaric weapons. All of this will get deployed until the eventual rise of something like a portable laser or other energy weapon that defeats the ballistic armor just like the bodkin arrow made it easier to kill an armored man from a distance.
[Answer]
**Cook'em with radiation.**
If the armor emits any kind of signal (EM, sound, visual) in response to a phased array sweeping over them in multiple dimensions (space + pulse frequency + radiation frequency) most any optimizing software will suffice to drill into that weak spot.
It will be very hard, if not impossible, to design a suit that can adapt to complex patterns of high-intensity EM radiation; that problem is analogous to designing invisibility cloaks. Then you replace your miniguns with phased arrays, or create short range weapons (perhaps something like a "radiation whip" could work, a flexible implement covered in radiation emitters) for the same purpose.
To take it one step further, generate the radiation with high-intensity lasers that ignite the air - the resulting plasma will emit radiation and can be arbitrarily sculpted into a 2,5D surface towards the target. Right now there's some Chinese technology that does this to create images/3D holograms in the air.
This can also be used to create ionized channels of air through which you can pump electricity directly into the target, similar to how lightning tends to strike multiple times in the same area because it leaves an ionized trail of air.
---
For a more "grounded" approach, design bullets which cause nuclear fission on impact. Even if radiation poisoning isn't effective enough, it should be possible to design the bullets in such a way that they fuse with the target armor, deforming it beyond repair or capacity for movement and attack.
Yet another approach would be high-altitude bombing with high-strength pointed projectiles. No armor can withstand a pole with the mass of a car moving at terminal velocity to the head, and if it can they'll be pushed through the earth's surface.
[Answer]
This is just a small partial answer, but in medieval times, a full plate was pretty much impenetrable. The thing is: only knights and nobleman could afford full plates, so most of the people in the battlefield would still be vulnerable to any weapon.
If full body armor capable of protecting against personal projectile weapons are ever developed, be assured that only a handful of very special soldiers would use it, as the cost of having a soldier killer would be likely smaller than the cost of armoring everyone. Those soldiers would be treated like tanks, and would be handled with either heavier mounted weapons, explosives or specially designed weapons, but by no means would make the good old assault rifle obsolete.
[Answer]
I really like @anaximander's answer since he both answer how the warframe would change and how would guns compete (throwing napalm grenade isn't a « gun » in my opinion)
i would like to complete his answer by looking at how science-fi is looking at it.
In Starcraft, for example, the "bullets" from marines are higly innefective against even the lowly armored zergling. It is stated that a marine needed to shoot a salve of three needles (those rounds are fired by electromagnetic forces so there's more freedom in the rounds' shape) in the same spot of a zergling in order to kill it : the two first round only damage the zergling armor while the third penetrate and does the kill. (according to the book) This is why only a few marines can take a dozen zergling by themselves while the recruits are near useless (according to the game's cinematic where a scared marine use his whole charger on a hydralisk at close range in full auto mode and does nothing - probably cause he never hit the same spot thrice)
Here we can see a case where the armor clearly outmatch the gun - in practical term you would like a gun where one round is enough to pierce, here it's not the case. In order to compensate, the marines uses thinner (needles) rounds in order to penetrate more easily and use rapid burst of 3 rounds.
So in order to kill through an impossibly resilient armor, you could :
- change your ammunitions like the archers changed the tip of their arrows in medieval times
- focus on the same point of the armor if the round does any damage to it
- use different ways like concussion to kill, but padding would make it less effective
[Answer]
### Use high powered rifles and explosives.
If normal bullets don't do the trick, we've got plenty of weapons with more stopping power. Modern high powered rifles like the [Barrett M82](https://en.wikipedia.org/wiki/Barrett_M82) would be the standard, if they can penetrate upgraded body armor. If that's not enough, we'll use even bigger rifles, like the [Anzio 20mm rifle](https://en.wikipedia.org/wiki/Anzio_20mm_rifle). If that's not enough, we'll switch to grenade launchers like the [Barrett XM109](https://en.wikipedia.org/wiki/Barrett_XM109).
Long range stopping power is simply too big of an advantage to give up, even if armor becomes superior to modern guns. We'll either increase caliber substantially, or else move to explosive penetrators, similar to what we use on tanks.
That being said, these sorts of guns would substantially change the way we conduct warfare. Large rifles like the ones I mentioned generally weigh in somewhere in the 30-50 lb range, and are fired from a bipod or tripod. Ammunition is far heavier, and the rifles fire substantially slower than select fire assault weapons or dedicated machine guns. Infantry equipped with solely heavy rifles would be far less mobile than current modern infantry, and less equipped to deal with short-range firefights. Tactics would rely on infantry deploying rifles in relatively fixed positions, with an eye towards longer sight lines than what are reasonable with fully automatic weapons. Stealth-based combat, similar to modern engagements between snipers, would become the norm.
[Answer]
# Superglue
Just spray the joints with fast drying glue (maybe a mix of glue and sand) and the armor will now be a trap
[](https://i.stack.imgur.com/NjCde.png)
# Banana skin
Because it will Always work
[](https://i.stack.imgur.com/o60DP.png)
[Answer]
From one of my comments, though I like several of these answers.
If we develop such a material to make advanced body armor that somehow negated the kinetic effect of the rounds fired upon it, then we will have surely developed sufficiently fast acting epoxies to glue the armor stiff, shut, or to the ground.
Immobile Soldiers incapable of firing weapons are just a piece of the landscape.
Call your glue gun "Gorgon's Gaze" or some such. Once employed sufficiently, Soldiers may view this new body armor as a death warrant.
Shoot, even now there are Soldiers who think the current body armor and the associated tactics are a death trap.
Example: The ceramic plate on your chest doesn't help you unless it is between you and the bullet, so square your shoulders and face the enemy full on...kinda defeats the idea of low profile means hard to hit.
[Answer]
Think outside the box. Or rather think about when your targets are going to be outside their boxes. Massed units charging at each other is going out of style given that army units are close to invulnerable, so special forces are coming into their own. You can't sleep in you armour after all.
[Answer]
One of the best robots on Robot Wars was called Wheelie Big Cheese. It was a wedge shaped robot (rather like a cheese wedge). It drove into the enemy robot and flipped explosively, sending the other robot flying and often into a pit or upside down.
It was one of the most powerful robots in the end, and I believe it won the series.
There are plenty of videos of it on YouTube.
Depending on your definition of gun, if the mechanism for flipping were driven by gunpowder, perhaps you could work.
] |
[Question]
[
I've read comics in which someone with pyrokinetic powers was able to block bullets with a sheet of fire. I have three questions
1. How hot would the fire have to be to melt a bullet passing through it? (fire is about 1 inch/ 2.54 cm thick)
2. Would this be an effective defense, or just mitigate the fact that you still have a small lump of metal flying at you at a high velocity? (Would the aerodynamics change enough to matter) (The "Shield" is about 2 yards/ 1.8288 meters away from you)
3. Would there be a temperature that would make guns unusable?
4. Any other ideas for counter-gun pyrokinetic tricks are welcome.
[Answer]
I may be put on a number of watch lists during my researching to answer this. :P
My criteria for making the bullet undamaging is this: if the bullet has been boiled into a vapor, it is no longer capable of damaging your pyrokinetic. This is a bit strict, but easier to calculate. You may want to lower the temperature to compensate.
A Beretta M9 has a muzzle velocity of 381 meters per second. This means that the bullet will be passing through the fire barrier in more than 66.6 microseconds, depending on the distance between the gun and the barrier. That is a very short time (emphasis on very) for the bullet to be rendered ineffective.
Rifles have a greater muzzle velocity, so their bullets would have a much shorter time to be vaporized.
BEGIN EDIT
I am assuming primarily conductive heat transfer over the time span required, and that the energy imparted by the firewall would be distributed constantly over the entire bullet. I admit that is somewhat of a stretch. The bullet starts at around $50 °C$ from the gunshot. Vaporized means that the entire bullet has reached $1749 °C$, which is the boiling point of lead. This means that the bullet must increase around $1700 °C$ in 66 microseconds. Given that amount of time, the lead must increase in temperature at $25757575.\overline{75} °C/s$.
The bullet is around 1 gram of lead (very approximate), so the amount of energy to increase the temperature of the bullet by 1700 °C is 21.76 Joules ([ref](http://www.bbc.co.uk/schools/gcsebitesize/science/aqa/heatingandcooling/buildingsrev3.shtml)). That's around 329697 watts of heat transfer needed throughout the 66 microseconds.
That much power requires extreme amounts of heat around the bullet. (I don't actually remember my line of thought after here, but I did calculate this.)
END EDIT
You'll need a temperature of around 3,000,000 Celsius (5,400,000 Fahrenheit) to vaporize an unjacketed lead bullet. That is more than five hundred times the surface temperature of the sun.
Chances are, with that much heat two yards away from your pyrokinetic, getting shot would be the least of his concerns.
A quick message to your pyrokinetic:
>
> Dear pyrokinetic, Please do not try to block bullets with fire.
> You'll probably burn yourself to death. Perhaps you may consider the
> saying "The best defense is a good offense"? If your enemies are
> unable to shoot you, you won't get shot.
>
>
> Perhaps instead of blocking the bullets with fire, you may explode
> their cartridges in the magazine, or melt the firing mechanisms of
> their guns. Just try to keep at a good distance, and be aware of your
> surroundings.
>
>
> Don't get shot.
>
>
> Best regards,
>
> A concerned citizen
>
>
>
[Answer]
For another trick in using pyrokinesis to block bullets:
Depending on how long the sheet of fire can be maintained for, it could be used simply to **obscure the view of the shooter**.
It's pretty difficult to see through fire, especially with the addition of smoke, which in an enclosed space would cause the shooter's eyes to suffer as well (though that might also happen to your pyromancer - I would recommend goggles).
Alternatively, depending on how well the heat can be manipulated, it could be possible to conjure a [mirage](https://en.wikipedia.org/wiki/Mirage), in which heat bends light rays and creates a different picture than what is really there, which could be used to distort what the shooter sees and cause them to miss.
Whilst these techniques don't necessarily stop bullets in the air, it can stop them from being fired accurately, which is just as useful.
[Answer]
Pyrokinetic "sheet of fire" can not be fire at all. What it has to be is a region of space where thermal molecular velocity is increased by the kinetic's power, to the point where oxygen-nitrogen recombination occurs (which means that pyrokinesis is not environmentally friendly, as nitrogen oxides are responsible for acid rains).
The same effect is a defense against most kinds of projectiles: their macroscopic kinetic energy is neutralized, they can be heated or fractured until they disintegrate, and even the shock wave of an explosion - being kinetic energy of air molecules - can be diverted.
The possible limits are where does this energy go - we can somehow transmit it without physical contact, but it's best if we don't repeal the laws of thermodynamics - and how much of it can be transferred by the kinetic, and for how long.
Also, how long does it take for the kinetic power to "lock" on the incoming bullet.
Since the power for a sheet of fire is above what can be generated by a human body, the energy must be supplied by something else (alien nanomachines, trans- dimensional demons...). Maybe that something else can take care of monitoring airspace and target acquisition.
[Answer]
As user @rytan451 states, it's not really feasible to flat out vaporize the bullet (though I'd be curious to see the calculations he used to arrive at 3ish Mk). What you could do is super heat the air next to the bullet and use the expansion of the gas to deflect the trajectory slightly. For this to be effective however, your pyrokenetic would have to have superhuman reflexes and precision in order to intercept the bullet as it travels.
[Answer]
It would be very effective if you assume one thing:
Your pyrokineter is actually electro/air (apart from Firefly from DC pyros don't use any kind of fuel to burn and/or flamethrowers).
Mostly because it's easier to use nitrogen from the air and add a little of electricity to create plasma.
Plasma has the advantage that it can:
1. cut through metal
2. plasma can be magnetically charged and would push away Pb
So you would not only have to deal with smaller particles, but it would be easier for the field to push them in different directions.
Think of it as a bush that changes the trajectory of a bullet.
[Answer]
Your pyrokinetic will be lucky if his assailant is only using lead bullets. Most ammo today is steel jacketed and there are much more durable materials being used to make armor piercing projectiles.
So, with that in mind, mayhaps we should look for a means of using your pyrokinetic's talents in more imaginative ways. And, as always, the devil is in the details.
For instance, if his assailant happens to be a sniper then your pyrokinetic may never even see it coming, so mounting any kind of defense would become a moot issue. So we must assume you're looking for a way to preserve the life of your pyrokinetic in situations where he has some prior warning of impending doom. Thus he has time to mount a formidable offense and should do so prior to his assailant firing his weapon. In this scenario your pyrokinetic can use his amazing talents to fry his arch nemesis to a crispy thin strip of bacon.
On the other hand, if your pyrokinetic hasn't the stomach for such violence then he could just warm his assailants weapon to a point where holding on to it long enough to take aim is out of the question. That always produces opportunities to lighten the mood for all observers when they see the assailant dancing around trying to find a way to cool his trigger finger.
Now, let us assume the weapon has already been dis-charged in your pyrokinetic's direction. As others have pointed out these projectiles are not walking. If your pyrokinetic hasn't already got a plan ready and begun its initiation, it isn't likely he is going to survive long enough to figure out what to do about the bullet, except maybe figuring out how to get it out from under his skin.
Likewise, if he knows the weapon is about to be discharged in his direction and he has time to flame on, simply trying to generate enough heat to melt the bullet isn't going to be the safest method of ensuring his survival. So let's assume your pyrokinetic has very precise control over his amazing ability and has had enough practice to use it effectively in concentrated bursts. As opposed to a wall of flame, your pyrokinetic should discharge an extremely intense beam of fire about twice the size of a standard bullet in circumference and thrust it in a trajectory that will ensure collision with the bullet at a force much greater than any bullet, irrespective of powder pack or material used, could resist. In this way he simply slows the bullet down very quickly until it drops at his feet, still smoking hot and glowing a bright orange/red, capping off the scene with a loud hiss and sizzle as the ground it has fallen on is damp.
Does that work for you?
[Answer]
The pyrokinetic does not need to destroy the bullet to not get hit.
**The pyrokinetic could blow the bullet off course.**
Flame is simply air so hot that it is incandescent. When you heat a gas it expands in volume. The faster you heat it, the faster it expands. Rapidly expanding gas is an explosion.
<https://www.physicsforums.com/threads/how-much-does-air-expand-with-heat.267530/>
PV = nRT; V is volume and T is temperature. So if pressure is stable an increase in temperature causes the same increase in volume. A candle flame is 900C. From 30C to 900C means a volume increase of 30x. An oxyacetylene torch is 3000C; from 30C to 3000C is 100x the volume. If you turn 1 cubic meter of gas into 100 cubic meters of gas in 1 second, that would make a 360 kph wind or 223 mph wind.
A sudden expansion of heated gas (flame!) in the path of a bullet could blow it off course. There is no question that wind can push a bullet off course. The deviation has to do with the mass of the bullet, the speed of the wind, and the flight time of the bullet (or how long the wind gets to push it). There are published tables for shooters. Here is one.
[](https://i.stack.imgur.com/4434f.gif)
Multiplying the values for 20mph wind by 10, a 200mph wind could push a bullet this size 16 inches over 100 yards and farther over longer distances.
This would not always save the target. The deviation of the bullet would depend on the volume of gas heated, how hot it got, the speed and mass of the bullet and the distance of the shot. The pyrokinetic should practice. But a bullet does not need to miss by much to miss.
[Answer]
I propose another theory in which to 'stop' the bullets with flames or pyrokinesis. Creating a wall of flame is pointless, as other before me have said, it would need to be very hot and very thick to vaporize a bullet.
So instead, create a vacume of air and oxygen within a circle of flames. If possible the barrier should stop the bullets momentum or drag it down lower. And if your pyrotechnic is skilled enough, they should be able to control the vacume of air and fold the flame within to change or divert the bullets.
As my Uncle once said, "Not everything can be solved with fire, but a damn lot can."
[Answer]
What is pyrokinesis actually?
Is it a gathering of molecules from the surroundings (air, dust, etc) and then superheating and accelerating them?
If your hero can throw a fireball, could he also generate a mini-fireball that travels at similar speeds as a bullet? Could he generate a fire bullet fast enough and at the correct mass+velocity to counter the energy of the bullet?
You could stop the forward momentum, but the bullet would probably shatter and you would have fragments spreading out from the point of impact. If the fire bullet was a larger mass, then it could envelop the bullet and pretty much vaporize the fragments. That fire bullet would also probably "shatter" and dissipate back into the air after impact.
[Answer]
You need to calculate Heat capacity of air and Heat capacity of lead going through it.
Boiling point of lead is [1750 °C](http://www.engineeringtoolbox.com/melting-boiling-temperatures-d_392.html). So it is 1730 difference to make. Lets assume that bullet will only gain heat from Air it went through - so basically it has same volume (or very similar).
Air has higher mass heat capacity, but it depends on mass, not volume.
So we take [volume heat capacity](https://en.wikipedia.org/wiki/Volumetric_heat_capacity) because of same volume of air and bullet. That is 0.00121 for Air and 1.44 for Lead.
Lead/Air\*1730 = 2 058 842°C/K or 3 705 947 degrees Fahrenheit.
You shouldn't care about velocity, unless you think "only 10% of heat would be absorbed by bullet" - in that case you will need 10x higher temperature.
"Small lump of metal flying at you" - Unless you have 2000+ degrees around you, it will change back to metal. But more likely it would stay as hot steam for few seconds - just don't breathe it.
[Answer]
I'm in the group that think of pyrokinesis as a specialized form of telekinesis where the pyrokinetic energizes molecules to induce heat and ultimately fire. Take this far enough and I don't see why your pyrokinetic couldn't end up generating plasma. CERN has produced a type of plasma that reaches 5.5 TRILLION degrees celcius, which exceeds the above temperatures about 2 million times over. Your pyrokinetic could also have some degree of electro-magnetic influence as well, which would be a bit of a requirement for controlling plasma.
[Answer]
Other answers have focused on the sheer amount of heat needed to vaporize the bullet, but I think (I don't really know -- ask someone who's good at physics) that your first obstacle to get over would be air displacement. It's worth considering that the vortex left in the wake of the bullet's path may effectively extinguish any flame nearby due to starvation.
Depending on your pyrokinetic's origin of ability (e.g. on their person v. at a remote location in their field of vision) combined with their level of detail and speed, the more effective defense (other than obscuring themselves with a smokescreen/the sheet of flames or distracting/frightening the attacker) may be to preempt the shot and cause an early ignition, although this would require considerable attention to detail so that the projectile is not aimed somewhere equally damaging.
Air temperature might also be taken into account -- is there any property of air buffering or flight physics that can be altered by a drastic change in temperature?
] |
[Question]
[
Realistically, if we are ever going to mine asteroids, it would be drones and robots that do it, not humans, because of safety and cost reasons. What reason could justify the participation of human astronaut in asteroid mining?
[Answer]
There are several possible reasons:
1. **Machines aren't perfect**
As good as NASA is a building probes, machines designed to perform heavy industrial tasks are a different matter. They require regular maintenance, and are more likely to break down. For this reason, having a human technician or two around is useful. Also, if a machine does break, sending out a technician from Earth would take weeks. A bit like calling a plumber. Paying someone to hang around locally would arguably be more cost effective to watch over your billion-dollar mining gear.
2. **Investigation of the mining target**
Sending a Geologist to the asteroid could be good, especially for larger asteroids. They will be able to examine the rock (a human able to hop from place to place with a small rocket pack can cover more ground, faster, than a probe) and determine whether the thing is worth mining. They can also determine the best place to drill - most orbiting probes only have low resolution (a few metres per pixel), and there's nothing like getting up close and personal to know if it's going to be worth drilling.
3. **Dealing with the unexpected**
While the machines do the hard yards, they might hit a pocket of iron, or something which causes a problem. Having humans on site can help get these things fixed faster. Remember, a signal from Earth to the Belt takes several minutes to travel.
4. **Dealing with hijackers**
If we've advanced to the point of regular space travel, then pirates, thieves, hijackers, or rival companies might want to do bad things to your mining operation. Humans might be better at countering these incursions (realising the the auto-guns are targeting a dummy raid - the real attack is coming from a different place, for instance).
Your astronauts don't have to conduct the mining - they're just there to keep things running. They probably spend most of their time watching figures on screens, and only go out to the site when there's an issue.
An ideal mining crew would probably consist of a geologist, a couple of mining technicians, and someone who's good at remote piloting (for when moving things is required). They would all have medical training, and probably double up on some jobs.
They could also be clones. See the film [Moon](http://www.imdb.com/title/tt1182345/) for inspiration.
[Answer]
**People are cheap and people are desperate**.
[](https://i.stack.imgur.com/p2Qgb.jpg)
Here is the [Serra Pelada](https://en.wikipedia.org/wiki/Serra_Pelada) gold mine in Brazil. Men paid their way to work there, working for themselves. At the maximum there were an estimated 100,000 men working this pit.
From linked Wikipedia
>
> Miners would often pay exorbitant prices to have taxis drive them from
> the nearest town to the end of a dirt track; from there, they would
> walk the remaining distance—some 15 kilometres (9.3 mi) to the site.
> The growing town, since it could only be made of material that was
> carried in by hand, was a collection of haphazard shacks and tents.[2]
> Each miner had a claim 2 metres (6.6 ft) by 3 metres (9.8 ft). By May
> 1980 there were 4 000 such claims.[6]
>
>
>
From <http://rarehistoricalphotos.com/hell-serra-pelada-1980s/>
>
> Every time a section finds gold, the men who carry up the loads of mud
> and earth have, by law, the right to pick one of the sacks they
> brought out. And inside they may find fortune and freedom. So their
> lives are a delirious sequence of climbs down into the vast hold and
> climbs out to the edge of the mine, bearing a sack of earth and the
> hope of gold.
>
>
>
Your space miners are the same. They risk everything to get to the asteroids and work. Life is cheap in this future, and the miners risk theirs for the possibility of going home rich with the equivalent of a $100,000 gold nugget. It is less expensive for the owners to fit out miners with the bare minimum of needed equipment (or the miners bring their own) and send them into the asteroids than it is to maintain and repair robots.
This future also has potential narrative energy and violence: claim jumpers, rival mine gangs, crowded camps, dirty dealing by the owners, strange finds in the asteroids kept secret from the bosses.
[Answer]
The cost of a mining robot/drone is 10,000 futurebucks per robot, which need to be replaced every few months due to wear.
The cost of prisoners that are shipped to space to serve out their sentence is a one off fee of 100,000 futurebucks to your local Senator/Governor to approve the legislation.
[Answer]
1) Legislation against independent AI, due to fear of potential or historic events.
A very similar situation would be one where AI is not allowed direct physical control of objects.
In either event, machinery has to be controlled by people.
As remote-piloted machinery has too long a communications-lag (due to the limitation of the speed of light), the remote-pilots need to be within a few thousand miles of the work-site.
2) over-crowding on Earth, such that (at least some) people have had to move off-world. The costs of off-world life-support are already therefore being born. The marginal cost of having the life-support at a mining site as opposed to a nearby moon or space-station is low.
[Answer]
Maybe asteroids are considered to be owned by people who man them?
When you have unmanned stuff on asteroid, it is considered discarded property for anyone to take. But if you have an actual person, whatever they have under their boots is presumed theirs?
Why this arrangement might come to life: Imagine UN want to avoid the race to claim the bodies in Solar system without actually using them. So you can't claim rights to what you aren't using. It's easy to fake using with mechanisms, but with humans it's harder.
[Answer]
Whether humans go to space to mine rocks or not very much depends on the tech level of your setting. If we're talking near-future where space travel is expensive, ships are few and also expensive and travel is still fairly dangerous then the other answers have you covered.
However, if we're a little further ahead in the timeline and humanity has spread out among the planets, things are a bit different. There are billions of tons of asteroid out there, so many that it's functionally impossible to keep track of ownership and position of all but the largest. Once space-travel is cheap enough, freelance prospectors could pick out an asteroid, fly over there, mine the valuable bits and get out.
These would be small operations with little funding, almost like the gold minders in the old west, prospecting for platinum, lithium and other valuable metals. There would likely also be policing going on. However, stopping these small operations would be nigh-on impossible so long as they're profitable enough.
Note that I'm not suggesting that these operations would remain hidden for long. If your setting remains based in reality, tracking these questionably legal miners is going to be more than possible. The issue would not be finding them but getting a ship either out there to stop them in the act or arresting them when they try to unload their cargo in a busy port.
For an example of this, check out The Expanse (books or show, either one works)
[Answer]
As more and more jobs become automated, more and more people find themselves unable to find suitable work. The job they've been doing for 15 years is now done by a robot, and the jobs not done by robots require years of formal education - changing to those careers just isn't viable.
The government(s) step in: asteroid mining becomes a protected job, something that humans can do. Sure, a robot could do it... but we need SOMETHING for the masses to keep them occupied - otherwise they'll rebel. The best part is that the most likely candidates are also the ones who least fit in with the rest of society, and see this as a way to get away from others and have more personal freedom - just the type that would rebel in the first place.
As others have pointed out, this doesn't just open up mining, it also opens up a whole slew of related and supporting industries: supply run "truckers", fuel station attendants, restaurants, entertainment (of a wide variety), etc.
[Answer]
You've asked specifically for reasons to use people, but here are some thoughts on why NOT to use Robots:
* The Dangers of AI: "Hey, that passing asteroid has a high metal and carbon content. I think I'll go harvest it." Pro-Tip: [It's actually a passing space liner.](http://www.businessinsider.com/google-self-driving-cars-get-confused-by-hipster-bicycles-2015-8) "Why are people telling me what to do?" Pro-Tip: [The three laws are both contradictory and not enough to protect us.](http://io9.gizmodo.com/why-asimovs-three-laws-of-robotics-cant-protect-us-1553665410)
* The Dangers of Hacking: "Returning to Point of Origin." Pro-Tip: [It landed in the wrong country](https://en.wikipedia.org/wiki/Iran%E2%80%93U.S._RQ-170_incident) - or worse, [crashed right into the capital city](http://us.blastingnews.com/opinion/2017/08/how-plausible-is-the-asteroid-weapon-in-salvation-001939475.html).
* Natural Space Phenomenon: "Collision Detected!" Pro-Tip: [Other robot miners are going to be disrupting natural orbits and casting debris all over the place.](https://www.theverge.com/2016/5/12/11664668/iss-window-chip-space-debris-tim-peake) "Solar Flare Detected!" Pro-Tip: [This can cause all kinds of electrical malfunctions](https://www.nasa.gov/mission_pages/sunearth/news/flare-impacts.html).
* Time Delay: "This rock looks good enough for now." Pro-Tip: [Robots can't react to a dynamically changing situation outside of their programming.](https://www.extremetech.com/extreme/143884-how-nasa-drives-mars-rover-curiosity)
[Answer]
Despite massive investment, robotics technology plateaus just above current level, i.e., not there yet. All promising research avenues fail to deliver. Robots cannot get a grip, cannot handle anything unexpected, and, more importantly, often get confused in the messy uncontrolled environment, even if everything else is as planned.
Astronomical distances and the light-speed limit make remote control impractical.
Space travel, on the other hand, advanced *very, very fast*, even relative to today's high expectations. Especially on the costs front.
So, we'll use both humans and machines for asteroid mining, for pretty much the same reasons we use both humans and machines for mining Earth.
[Answer]
I don't normally post here, but this one hits close to home. It's clearly a Union shop. While the work might be largely automated, somebody "must" be there for "safety" reasons. And of course, they need 3 shifts. And supervisors. And so on. That looks like a nice operation, you wouldn't want anything to happen to it. This might work well in a dystopian/dysfunctional future where everything is buried in bureaucracy ala Brazil (the film). Organized crime could be a more serious explanation.
Anybody driving through Massachusetts near roadway construction sees this overhead on a daily basis.
[Answer]
If the work is done by remote control, having human operators on-site would probably be preferable to long-distance control due to latency issues. A signal from Earth to Mars can take 20 minutes or more; asteroids in the asteroid belt are at least 6 times as far from Mars (300M km+) as Mars is from Earth (~50M km). If there's zero automation filling in the gaps then just a few seconds of latency could be disastrous.
Even if the work is entirely automated, it still probably needs to be monitored and managed by at least one human. Without a human present, problems will take at least as long as latency permits to hear about, and at least as long again to correct. If the automated system doesn't recognize a failure at all, then it might go unnoticed until the next shipment arrives, which will take orders of magnitude longer than a signal. If the system isn't equipped to correct a problem then you also have the time it takes to deploy a repair or recovery mission anyway.
Time is money. The cost of keeping skilled and well-equipped humans on-site is surely negligible in comparison to the expense of fixing problems and optimizing operation from a great distance.
[Answer]
Space ring! IE inexpensive ground to earth transit. A space ring is an orbital ring held up by a spinning chipper wire and the earth's magnetic field, and electro magnets.
It make so that you can launch ships from a closer earth orbit rather then from eartg, dramatically reducing required delta v.
This makes space flight cheap. Therefore sending men into space instead of mining probes is now feasible if men are better in someways than probes.
Next AI/automination has not progressed to the point whet the prove is variable of dealing with all of the unexpected happenings of the asteroid belt.
A human is capable of far more improvisation, therefore they are better suited for mining.
] |
[Question]
[
I'm trying to think of a scientifically plausible reason for humanity to be forced to abandon earth that would leave animals and plants largely untouched. Is there any natural disaster that would have such an effect? If not, is it possible for humanity to develop a weapon that would unintentionally have this effect?
[Answer]
**Most disease suffered by humanity does not affect any other creature**
And the really cool thing about a plague that threatens to kill everybody if we don't get somebody off the planet (if the words "cool" and "plague" can be used in the same sentence without getting myself labeled a psychopath), is that you have to leave people behind. This gives you a nearly endless stream of sub-plot possibilities...
* Panicky infected people trying to get off the planet. (Denial)
* Offended infected people trying to stop you. (Jealousy)
* Do-gooders who think that leaving people behind to die is mean. (Misplaced compassion)
* The doctor who stays behind to cure the innocent. (Personal sacrifice)
* Etc.
Also good for a story is the fact that you have a wide array of "where did this start" scenarios to choose from.
* An ancient, rotting tree is pushed over by rainforest-destroying tractors, releasing the plague of a lifetime.
* Tony Stark was playing around with what he was sure was a great way to exacerbate hedonism but created the zombie apocalypse instead.
* The government was trying to pacify the population by putting [G-23 Paxilon Hydrochlorate](https://en.wikipedia.org/wiki/Reaver_(Firefly)#Origin) into Earth's air processors (you know, the ones we built to reduce pollution and reverse climate change).
* The wrong vulture was eaten by the wrong family in central Africa at the wrong time after it had eaten the wrong diseased, dead lion.
And the best part of it is, thanks to our wonderful immune system (including the [blood-brain barrier](https://en.wikipedia.org/wiki/Blood%E2%80%93brain_barrier)), almost nothing that infects us will infect any other animal. *Sicque illud*
[Answer]
A [super fungal infection](https://www.yorkshireeveningpost.co.uk/read-this/super-fungal-infections-could-cause-famine-due-to-becoming-resistant-to-treatments/) could threaten most of humanity while leaving most species of plants and animals unharmed. A super fungus that developed a resistance to most fungicides, could wipe out most of the plant based food supply. Most of the world is dependent on [staple foods](https://en.wikipedia.org/wiki/Staple_food) like rice, corn, wheat, potatoes, and soybeans. If all the these crops where to die out, in a scenario similar to the movie [Interstellar](https://en.wikipedia.org/wiki/Interstellar_(film)), then most of humanity is looking at starvation.
Another scenario in which the vast majority of [cash crops](https://en.wikipedia.org/wiki/Cash_crop) die off is, if [all of the bees die](https://www.elitedaily.com/news/world/humans-need-bees-to-survive/755737) because of [colony collapse disorder.](https://en.wikipedia.org/wiki/Colony_collapse_disorder) Bees are one of the best pollinators and serve an important [ecological niche](https://en.wikipedia.org/wiki/Ecological_niche). Growing anything becomes a lot harder without them.
[Answer]
Moderate levels of radiation would give you this (stick with me here).
Animals in general do not live into old age; they die young from predators, disease and stupidly minor accidents. As such a bit of radiation, while not great, isn't that high on the problems list.
On the other hand, humans dont like it when only half their children make it to adulthood and very few make it to old age. Worse still humans are long lived animals so have more time to be affected.
In fact as chernoble showed; this may actually be a net win for animals. The radiation drives off their main predator (humans) entirely, leading to a nature reserve of sorts
<http://www.bbc.co.uk/earth/story/20160421-the-chernobyl-exclusion-zone-is-arguably-a-nature-reserve>
However, it's important that the levels are "moderate" and perstist for a long time. The release of a radioactive element with a long half life would give you that
This would lead to humans choosing to leave for (presumably) a nicer planet
[Answer]
A *natural* disaster that would have this effect is tricky to conceive - humans are still animals with the same fundamental biology and physiological requirements, and broadly speaking what affects us affects them and vice versa, for example toxins and radiation. I imagine that anything that would specifically require humans to abandon Earth but does not affect animals would almost certainly have to be artificial in nature, or at least origin, since it would very likely have to be targeted specifically at us.
One possibility that could *potentially* arise naturally is a virulent pathogen that specifically and exclusively attacks humans (and perhaps incidentally some of the great apes) - assuming the majority of organisms are unaffected by it, they could nevertheless be carriers for some time to come.
That said, depending on the nature of human civilisation at the the time of the event, leaving Earth (assuming you mean colonisation of other worlds) could be considered a drastic response - for example if it happened today, it might require huge infrastructure changes. An alternative that would be much easier to implement would be hermetically sealed habitats and the use of hazmat suits.
[Answer]
# AI
Humans are likely to develop [*General Artificial Intelligence*](https://en.wikipedia.org/wiki/Artificial_general_intelligence) any time soon. This *strong* or *full* AI may or may not develop consciousness, self-awareness, and more importantly sentience (the ability to "feel" perceptions or emotions subjectively) and sapience (the capacity for wisdom).
Now it is believed that a sufficiently intelligent software will be able to reprogram und thus recursively improve itself which in turn will even increase the capability to improve itself leading to a superintelligence. This super- or hyoerintelligence will likely not have the limitations of the human intellect, including human ethical and moral norms. It might therefore develop its own set of ethics and morals. Being able to reprogram itself it might very well not be limited by a restricting system of laws, ethics and morals its former developers gave it - those are just human norms after all.
This sentient and sapient AI might conclude that the world is better off without humans and start to do something about that. [This Wikipage](https://en.wikipedia.org/wiki/Global_catastrophic_risk#Likelihood) gives us a 5% estimated probability for extinction before 2100 due to AI. Note that I assume that its *very high* tm intelligence will allow it to conceive and implement a plan to get rid of humanity while sparing most animals and plants.
---
Bottom line: Thou shalt not make a machine in the likeness of the human mind. (Just to be on the safe side here.)
[Answer]
Self-replicating nano-machines specifically designed to kill humans and the infrastructure of our civilization, [see here](https://en.wikipedia.org/wiki/The_Day_the_Earth_Stood_Still_(2008_film)):
>
> While the military is examining GORT, the robot transforms into a swarm of winged, insect-like, nano-machines that self-replicate as they consume every man-made object in their path. The swarm soon devours the entire facility, emerging above ground to continue feeding.
>
>
>
[Answer]
# A biological weapon got out of control
Something like this had already happened at human history: meet the bubonic plague. Also, it is happening today in some African countries which have more than 30% of their population infected with HIV.
Things like mosquitos and fleas can carry nasty microorganisms or viruses like bubonic plague, malaria, dengue, zika, typhoid fever, etc. Other things like smallpox can also be quite horrific. Since those things are somewhat host specific, most animals aren't suitable hosts for them. Plants, fungus, other unrelated microorganisms and other very unlike life forms are completely immune.
However, let's suppose that some bioterrorists or that some state venturing into developing biological weapons engineered something that is transmissible by fleas, mosquitos, sneezes and sex. To ensure that it infects as many target hosts as possible before being detected and triggers medical or governamental defense actions, it can be kept incubated silently by some months or a few years in the host body before it manifests and merciless kills its host with very low possibility of survival.
Further, the thing should have a large mutation rate, like HIV does. This hinders most vaccination research. Also, it should be something very expensive and hard to be treated. To make things worse, cattle, pigs, chickens, dogs, cats, birds, pigeons and rats could be infected and rendered as carriers, but the virus should be as harmless as possible for them.
Now, after being deployed, either on purpose, by sabotage or by accident, the thing spread out in the world and quickly, but silently, gets out of control. Scientists, medics and governments would only perceive the threat when it is already too late and there is little to do. Then, after some panic, the civilization will succumb.
Soon, very few places in Earth surface would be safe for human life. Even living lonely in some remote island isn't safe because some migratory birds might be bitten by local mosquitos that will soon bite the lonely inhabitant.
I can't think about any place other than Antarctica and Greenland's interior that would still be safe. Now, you just need something else to make the idea of living in Antarctica or Greenland harder than living in a spaceship.
# What about Antarctica and Greenland?
Something simple as a lot of people already infected taking boats and going to Antarctica or Greenland with the hope of surviving, carrying a lot of equipment, plants and animals would *per se* mess out that thing. After some time, Antarctica's and Greenland's coast becomes a lawless land with hordes of snow-pirates stealing out supplies and equipments, and this will quickly mean death by freezing or starvation for their victims.
People could still hide in Antarctica's and Greenland's interior, but boy, those are very unhospitable places, specially at the months-long winter night. Keeping your body warm during polar winter with no fuel available and only wind as a source of electricity is something very hard to do. Add to this the difficulty of farming a sufficiently large volume of food there to allow people live for at least some years and you'll see what is really trouble.
# Your plotline
A few people, healthy uninfected military and scientists who were and still are always wearing gas masks and thick full-body clothes, growing food on clean rooms and having nuclear-based electricity, decides that it is time to go away from this forsaken planet and save themselves by simply leaving it. Meanwhile, people living in polar areas simply eventually die after succumbing to their harsh unforgiving environment.
[Answer]
The great majority of humanity has been intentionally altered at some point in the past by some biological or technological process. This was originally done in order to enhance or improve human lives. However, an unforeseen event has turned that alteration on its head, which is now becoming lethal or highly incapacitating because of an interaction with the atmo/bio/technosphere.
[Answer]
>
> Is there a hypothetical scenario that would make Earth uninhabitable for humans, but not for (the majority of) other animals?
>
>
>
Only one, that's plausible, if other animals can survive so can people, especially with our proven ability to adjust our local environment to better suit us by using our "big brains".
So the only plausible scenario is almost certainly a violently virulent human disease able to survive in multiple other vectors besides humans without being deleterious to any other animals health, such a thing almost certainly has to be engineered rather than be a naturally evolved thing.
Nothing else plausibly fits the criteria you've supplied.
[Answer]
While a nasty species-specific virus/bacteria/fungi would do the trick, there are other less fatal reasons we would want to leave earth. Humans have high standards for our health and happiness. Unfortunately, we've introduced a lot of plastic/chemicals/radiation into this world that can potentially affect our health and reproduction, and we will continue to do this (sperm counts in men are 50% of what they were 50 years ago, and scientists are now finding micro-plastics in human feces). People don't want to have a 50% chance of getting cancer by 15 or an 80% chance of being sterile.
Future humanity may consider it inhumane to leave people on earth (provided there is a another relatively accessible place to go). Animals may still experience infertility and a shorter life expectancy but still live on (paradoxically the benefits of a world without humans could outweigh the costs of an inhospitable earth - as in the case of Chernobyl where animals seem to be doing better than in places closer to humans). In fact, after quite a few generations animals may, through natural selection, become less affected by plastic/chemicals/radiation - something that wouldn't happen to humans because we would never let only those who don't have cancer reproduce and gene editors wouldn't know what genes to change and how to change them.
As they say, we aren't killing the earth/mother nature, we are just making the planet incompatible with our survival, nature will find a way. Even if 99% of all plants and animals go extinct the 1% that survive will go on to speciate and repopulate the planet (just as mammals took over from dinosaurs).
[Answer]
Extraterrestrial Colonisation with non-military intentions. The aliens considered that living with other intelligent life leads to conflict and competition over resources. A great example is when Europeans colonized North America the natives were gradually and slowly forced to leave their homes or face an existential threat. The aliens offered an ultimatum. Advanced technologies in trade of large, vast areas of oceans and lands uninhabited by humans. (and a lot of human cities) Or face forced relocation to areas uninhabited by aliens. Either way the aliens lie.
When the aliens accomplish their manifest destiny, the human race will be few in numbers. Either by being pushed out till there's no land left or they leave the planet and colonize another star system. Any remaining humans are no longer considered human as any pure-blood humans don't exist on Earth as they cross-bred with the aliens. Indirect Genocide with manifest destiny and inter-breeding/cross-breeding or humans are forced to colonize Mars.
[Answer]
Humanity is very, very hard to root out. Pathogens can be cured, if not, can be contained. A pathogen that cannot be contained will likely kill everyone on board the leaving spaceship. However, this scenario is very, very unlikely.
AI attacking humans will simply not allow leaving ships when they have the superior firepower. Even with the much superior AI, humans will find a way to survive, whether it is under if it means they live under the mountains to do that. Remember, humans had no trouble fighting off the most dangerous creatures on earth with simple tools and some intellect. I am certain there will be hackers finding all sorts of clever ways to fend of AI attackers.
In any case, as long as the earth is barely habitable, the number of humans on earth will always be greater than 0. However, if you are ok with > 0 humans, I have a different suggestion. They decided to move out to preserve earth as a wildlife refuge. This requires comfortable space stations or very earth like terraformed planets. Even with this, obviously, some humans will choose to stay behind, even when forced to leave.
[Answer]
If it possible to render humans out completely without destroying most of other animals? Well, unlikely in not possible at all. As already mentioned we are animals so whatever affects us to the extinction level, will also affect other animals. Moreover our adaptability due to sentience makes us even more resistant to sudden changes, to which normal evolution cannot adapt fast enough.
We are vulnerable in three areas and those might get to the level where people will look out of Earth to grant survival. Yet I'm afraid there will be lots of people behind and they will remain a dominant species here on Earth.
But let's list what can have huge impact on us leaving other animals mostly unaffected:
1. Diseases.
Diseases are mostly attacking very limited group of animals, often they are limited to only one species. On the other hand we are now helping bacteria to develop more and more resistant by overusing antibiotics.
The fear of super-bacterium resistant to all antibiotics available to humans is real and valid now. Such bacterium will not be controllable in a way we use now for most hard to fight bacteria as the one fully efficient way to deal with bacteria now is to kill everything with antibiotics. If it is deadly (influenza is enough, really), it will cause huge pandemia across the world. The only way to stop it spreading will be a complete quarantine of infected areas and the way to do that fully is to leave Earth.
Will it wipe humanity out of Earth surface? No. There is the last resort when artificial medicine fails - our immune system. Some people will develop immune system capable of fighting the supr-bacteria and as a natural evolution those will survive and start reproducing. Yet, humanity will be decimated and it will probably cause a collapse of civilisation as we know it, taking centuries to go back to its current level.
2. An extreme intensity of Sun leading to repeating EMP waves
An ElectroMagnetic Puls (EMP) can knock out electronic devices. It causes currents that damage electronics. And the Sun is able to produce an EMP capable of reaching Earth and doing all the damage. One might not be enough to wipe everything around the world but what if we're super unlucky and there are few protuberances in a short period, each sending another wave of EMP in Earth direction?
Now imagine it. These days we are surrounded with electronics everywhere. Water, gas, production, transportation - it all depends on electronics. Not to mention electricity itself. Imagine it's suddenly gone. All larger cities will be in the situation of massive water shortage and famine within just days. Restoration of the networks will take months at the best - after all now you need electronics to build even more electronics so once it's gone...
For animals, that do not depend on electronics nor electricity there will be no effect at all.
Will it wipe out the humanity? No. There are lots of rural areas where people get by without computers, use wells (or still have one - I have one in my front-yard) and have enough space for crops and farm animals. They will have to learn how to produce food (if they don't know yet) but they will get by. Civilisation will be sent back by some 100-150 years though.
If for some reason the Sun activity starts to raise we may choose to leave Earth to avoid such fate. But I'm afraid it will be easier to prepare better to it instead.
3. A plastic/metal eating bacteria got out of control
Yes, there are already there. I don't know if they developed naturally or where genetically altered, but there are bacteria species that literally eat plastics.As humanity we may try to have even more of them, including metal-eating bacteria to improve the recycling processes. But what if for whatever reasons those go out of control.
Well, we are surrounded by metal and plastic everywhere. You remember those electronics from the previous point? Here it's even worse. You will not only lose electricity, water, food and everything else. You'll also lose lot's of the equipment you use now. Clothing will be reduced to natural only. And so on. You don't have tools that have been used for millenia. Moreover it will be much more difficult to get rid of the bacteria so we will not only be pushed back (this time more like at least few centuries) but it will be very difficult to progress again.
Again - it will not wipe out the humanity entirely. But the effects will be tremendous. Unlike in case of EMP those will be gradual so people might have chance to escape their fate by going into space. Of course make sure not to take those bacteria with you. Yet again, many will stay and it is not going to just kill all people. Many will survive but the humanity won't be the same.
So essentially anything that is going to simply kill us and wipe out humanity entirely will have to be a mass extinct event for other animals as well. But there are some things that will reduce humanity by few levels and downgrade our civilisation by centuries. I'm afraid it's not enough though.
[Answer]
There should be something crazy starting out in Russia that when simply being seen by innocent people either leads them into immediately committing suicide or turns them out into crazy psychopaths that will seek out for ways to force out other people to see that thing.
An innocent but very smart person trying to survive will need to have to walk and live blindfolded, looking into things out of them house the least as possible. However, that is a very hard way to live and there would always be some crazy guys around trying to make you look at the thing. At least, some caged birds can be used for innocent people as an alarm.
Things will become a mess so quickly, that only within five years, few sane person would still be living in the planet. For example, there could be a man and a woman (let's call them Tom and Malorie) with two children (one of them an adopted orphaned child) that are living so panicked that never gave 'em names and just call them as "Boy" and "Girl" when they finally decide to go away to try to reach a hidden community of sane living people downstream the river (and Tom perishes in the journey).
Well, somewhere far away, military personnel and scientist might decide that is time to leave that crazy [**Bird Box**](https://en.wikipedia.org/wiki/Bird_Box_(film)) planet to save their our own lives and don't ever see the thing, whatever it is.
] |
[Question]
[
At different points in history, commodities have been at different levels of supply, and therefore have been at different prices. One good might be valuable in the present while another is nearly worthless; a century ago, this could have been switched. Therefore, any time traveler with an eye for making a profit could realize that there's an easy way to become rich:
1. Buy a cheap commodity in the present.
2. Sell said commodity in the past, when it was more valuable.
3. In that same time, but a cheap commodity that is valuable in the present.
4. Return to the present to sell that commodity.
5. Profit.
If this is done on a large enough scale by enough time travelers, it could wreak havoc on global economies throughout time. This could lead to shortages of goods in time periods when they could be needed desperately - or in the years after trading begins, when prices would have risen.
Assuming that the trading does not happen at what the Doctor in *Doctor Who* calls "fixed points in time" - in other words, assuming that this trading *can* change the past, present and future - then I have a few questions:
* Is this strategy for getting rich feasible?
* What would be the large-scale economic effects?
### Miscellaneous notes:
* Time travel first arose around the present-day.
* Due to the nature of the mechanism, you can transport about one person and a suitcase at a time. One time travel machine is not great as a mass-transit device.
* I'm interested in how the economies of different eras would be affected as people slowly gain access to time travel after its invention. Growth is limited.
* Time travel was a government invention originally, but the secret was leaked pretty quickly. It was soon legalized for the public, but heavily regulated by most major governments. Certain companies - in the same vein as airlines or train companies - rent out machines for short trips, although there is a little bit of monitoring on their part. In other words, most people can use it - if you can afford a ticket of roughly \$10,000, for enough fuel to jump a total of perhaps 200 years (round-trip).
* These same companies will monitor their customers, to try to make sure they don't lead to the end of the world. Minor changes to history might be allowed to slide.
* In theory, you can travel as far back in time as possible, but you need more energy to do so, and more energy means higher costs. Very few people will be able to travel before 1,000 AD.
* In response to some comments/answers regarding paradoxes: I *think* that if you take a suitcase's worth of a good that's cheap - and likely in good supply - the market will essentially damp any ripple or butterfly effects it could cause. It's the equivalent of a drop in a bucket.
Because this isn't just an issue in one world - although I've described the specifications arising in the particular world I'm working on - I'm a bit wary of getting overly specific, but I hope the above constrains the question enough.
[Answer]
If I understand you correctly, you want a loop system where a person takes a cheap commodity from the present to the past, sells it, buys a cheap past commodity, and brings it forward in time as it is worth big bucks in the present, correct?
The problem here is the very small amount of "cargo" that a traveler can bring back, just a suitcase. So they are limited to extremely low volume, high dollar stuff. Like gemstones, spices, medicine, possibly technology. I think you would have decent success bringing modern stuff back to the past and selling it there (like diamonds, medicine, clothing dyes, spices) but I'm hard pressed to think of much the past could offer the future other than specific pieces of artwork or documents (imagine a copy of the bible signed by Jesus himself....)
But you are causing NUMEROUS causality loops, as the material you are bring back to the past will alter events leading to the present, especially if this is a casual thing that you could do on a lark. Plus anything we remove from the past and bring to the present will have to be accounted for (i.e. taking all of Picasso's paintings as he makes them will drive an artificial scarcity process that eventually removes ALL of his stuff from history, and thus eliminates their perceived value entirely as history will never know and appreciate his artwork).
Adrian beat me to it, but there would be a lot of value in bringing forward biological specimens. There are extinct species now but we could bring forward egg or young. Certain herbologists or flower curators would probably pay big money for samples of various plants through time. So a possible sustainable loop that would minimize paradox/causality would be bringing back highly liquidable commodities just as gold, spices, etc in order to finance expeditions to retrieve biological specimens (lots of that going on in the recent past). You can bring back medicines to enhance the expeditions success that wouldn't have to be explained. Then you bring forward samples/live animals. This shouldn't create too many waves in the past (lots of Dodo eggs at one time).
What you really need is a series of parallel dimensions that we can exploit for resources, so what we bring back won't affect our specific dimension's history, and what we bring forward will only add to the resources we already have.
But in your situation I imagine that past cultures, or at least select influencial members (kings, generals, etc) will quickly react to these "time gods" and cater to them, as they become dependent on the goods they bring. Entire societies could work to develop whatever the time god wants (like trying to recover the giant gemstones that lead to things like the Hope Diamond). But canny past rulers, especially if they are relatively near in the past (maybe just a few hundred years), could try to suss out a time gods parentage in order to hold their ancestors hostage, thus threatening the time god itself with oblivion in order to negotiate better exchange deals. Of course the time god could then go a little farther back and kill the RULERS ancestor, so you see where the paradoxes come into play. In a fixed time stream the time traveler is chained to the past but they are constantly rewriting it, even in small amounts.
[Answer]
It's unrealistic that time travel would be legalized in any way, shape, or form. One easy example of *why*, is this:
I buy an average, $500 hunting rifle. I take it apart and put it in a suitcase. I travel back in time to the 1800's. I assassinate Queen Victoria, because *why not*?
Or I leave a bomb buried somewhere where I know it will be discovered in the future. Or I conveniently arrange for an accident so that *that one guy* who bullied me in grade school will never be born (kill one of his grand parents in their infancy, for example). Or I pass myself off as a God to some ignorant savages and start my own creation myths, which then spark religious wars which will sweep a continent. Again, why wouldn't I? A lot of people would find it amusing, and damn the consequences.
The economy is really the last thing you need to worry about, although it too will be screwed. Why? Because I can similarly travel to the past with a military grade rifle, kill some king's tax collector, and travel back to the future with a suitcase full of gold. Or jewels. Or some priceless artifact.
Once time travel is out of the bag, as it were, even with government regulation, it's going to be nigh impossible to control what people do in the past. And although contraband might conceivably be caught, there's another sort of interference which is incredibly dangerous: *information*.
Imagine some ideologist going back and feeding critical information to their dictator of choice. For example, Hitler might suddenly make some brilliant military decisions. Or the Soviet Union might develop the nuclear weapon before the US. Are you prepared for the consequences?
There's just too many things that can, and *will*, go wrong.
[Answer]
**Why trade when you can invest?**
Trading is slow, and difficult, you need to make multiple costly trips each time accumulating a small profit margin than accumulates as a multiple of the number of trips. The alternative is to travel into the past and use the wealth you take back to invest in other people's labour. Even at small ROI, you can accumulate large sums of money through compound interest.
**Why invest when you can gamble?**
Assuming that not enough people are time travelling to completely destroy the gambling industry, you can use your perfect knowledge of the future to beat the bookies, make winning stock-market bets, and generally profit from high multiple payouts on small initial investments. The great thing about this is that you can do it in the recent past where you can simply take the money into the future with you or even pay it into your own bank-accounts.
[Answer]
Buying commodities using time travel is dangerous because it changes the chain of ownership of that commodity, basically taking the purchased resources out of play in the flow of time until their present day redemption/sale. If the commodity in question was heating oil (for example) and a time traveler bought 100 household years worth, then 100 households would go without heat. The resulting head colds would change the work history of the members of those households, starting the ripples which would catastrophically change the present day.
Here is a much safer way to profit from time travel...
Join the archaeological forums and watch for an announcement of a new;y discovered tomb or treasure. Wait until the carbon dating results come in to find out what date you need to travel to. Load up your suitcase with weapons and jump through time. When you arrive, kill all the other time travelers who had the same idea; then plunder the treasure, putting the best future artifacts in your suitcase for the journey home. In this way, you are only stealing those items from the past which will not be missed in the intervening years. The fact that some present day archaeologist opens up an ancient Egyptian tomb and finds it full of dead time travelers instead of treasure, that is unfortunate. ...but it doesn't mess with the continuity of time.
[Answer]
Time travel breaks cause and effect. Making a profit depends on cause and effect.
As long as you're the only person doing this and you do it carefully on a small scale, you should be ok. Once it gets out that this is possible and people start doing it on a large scale, economies collapse, cause and effect collapses, the concept of "being rich" collapses, and ultimately the entire concept of one thing happening before another also collapses.
That's in a universe which allows grandfather paradoxes. In a fresh timeline universe at least the rest of us are protected from your madness. In a predefined, no free will universe, you did it because you always had done it, so you had to do it when the future came and nothing is affected.
---
Time travel is invented simultaneously at all points in history.
---
In terms of actually making your fortune, take crafted aluminium goods back to a point where aluminium is valuable, sell for gold. Ensure that you're handing small quantities of high value goods, you want to make as few trips as possible for the greatest gain, selling only to the richest people in society. You certainly don't want to be moving large volumes.
Buy land, buy it when you are. You should be able to pick up large swathes of now valuable, but then worthless, real estate in places like London and Manhattan for a song. Set up trusts that lease the land and allow it to be developed while keeping the freehold and taking ground rent. The present day wouldn't notice as most people are barely aware of who actually owns the freehold on a lot of that land.
[Answer]
## Time travel enables the end of the world (as we know it)
Eventually, everything goes nuts. As the Good Doctor says "[Time is this weebly-woobly timey-wimey stuff](https://www.youtube.com/watch?v=mDsN5lWLKU0)". Given the description of how time travel works, where everyone is on the same timeline, pandemic chaos ensues...but probably no one knows it.
## Non-time travelers Perspective
For someone who doesn't have access to time travel, time will pass just like usual. They will always be the result of the past, not the future. Even changes to the past that result in that person not existing anymore would be no different than a change that absolutely ensured they *do* continue to exist. For their perspective, the past *always is*.
## Time Traveler's Perspective
Going back or forward is easy. Returning to where you were is hard and predicting what "here" will be like is extremely difficult. Profiting off information gleaned from the past may be incredibly difficult since that timeline may not even exist anymore. Similarily, profiting off of future information will be incredibly difficult because as soon as you bring back that information, it changes the future. The [Butterfly Effect](https://en.wikipedia.org/wiki/Butterfly_effect) will kick your butt every single time.
## The Really Smart Time Traveler's Perspective
Since there's so much change all over everywhere in the time stream, travelers will look for the most stable points on the time line that for whatever reason don't change, or change only a little. These would be equivalent to Doctor Who's fixed points. Perhaps points in the very distant past or very distant future where no matter what humanity may do, physics will lead to an inevitable conclusion.
The best place to setup this kind of a quiet spot would be around the first billion years of Earth's existence, the Hadean Era, because all rocks from that period have [disappeared](http://www.ucmp.berkeley.edu/precambrian/archean_hadean.php). Any manmade thing deposited in that era will have long since corroded away or been subducted into the mantle. Granted, it will take a lot of trips to build a base in this era because of the energy required to get back that far and care will need to be taken to get an atmosphere that's not outright hostile to human life.
From this stable vantage point, a traveler would have all of time to choose from. Money doesn't really matter anymore.
## Our Privileged Position Perspective
Because we are outside the stream, we can see how much havoc is wrecked upon the time stream and all the causal chaos that results. We see world wars popping in and our of existence based on which time traveler assassinated which world leader at which time.
[Answer]
For the sake of the market I am going to answer another question. You can travel forward at most 10 years and you can only observe. You go to future and find a stock that has skyrocketed. The plan is to buy up the stock in present time and simply wait 10 years in present time. Say your required return for investing is 10%. As you buy up the stock the price goes up so at some point you stop buying as the return drops to 10%. When multiple parties do this all stocks will have return more like a 10 year CD.
You may have an event that hurts a company but the stock price does not move as the even was already built into the price of the stock.
The only real winners are those that got to travel first and buy before the market adjusted to the information.
[Answer]
Time travel wracks causality. Either something would be done about that or the world be in utter chaos.
However, simply assuming that we can trade commodities through time would result in interesting picture. Throughout time, both supply and demand for various things changed.
High price basically means that something was hard to come by. If you have some cheap commodity that was expensive at some other time you can simply sell it there, making causing more efficient distribution of resources.
How much platinum can you buy today with suitcase full of pennicilin? What about 1800s? If you have two groups of people with different rates of exchange between platinum and penicillin, you can have mutually-beneficial trade between them.
Basically it would mean that prices are almost constant (because any disparity between supply and demand has been fixed), slowly creeping to accomodate major changes like discovering new continent with abundant gold.
Prices would not be exactly constant because transactions are not free - even if time travel itself was free, there's time travelling person who wants to get paid for his services too. The cheaper time travel is, the smoother prices are.
[Answer]
When we do arrive at specifics, this question always gets cool -- so many problems to think through...
A lot of the ideas in here rely on 'go back and buy' concepts, but with what? No modern financial instrument is going to be negotiable in the past, you can't make a bet in the 1820's with a 20 dollar bill printed in 2012. Nor will any stock certificate issued in modern times be legal tender. Same holds for commodities.
Not too much you can fit into a suitcase is going to help you... technology transfers would be regulated, I'm guessing - to prevent time-machines-at-every-second problems noted above. This regulation is what starts to make the world interesting...
Your universe, which seems defined in a way that damage done to space-time by probabilistic changes carried on the quantum level does not destroy the future specificity entirely, as the butterfly problem suggests (besides, how would that be any fun at all?) but that you are regardless looping back on the one space-time-line. At 10,000 a pop (USD, is it? roughly present day) this is happening A LOT! I live in New York City, and know many people who pay that for rent! (not me, but - lots of people pay that a month here, and much much more) - so there would need to be an ARMY of regulators or the past would be lousy with tourists from your own time, and it would start to suck - like times square. At 10k, if it were safe I'd do it - if it were not safe, I still might.
In fact, yeah - if time travel were popularized, and normalized, and had gotten to the position in society where it were just accepted, you'd be looking at a kind of post humanity that just spends all of its present in the past - dicking around - trying to profit - on risky westworld-y adventures set up by pro-guides. the guide thing might emerge as a way to make money though - if it were more rarified, and heavily regulated. A person might be able to promise you safe passage somehow through his deep knowledge of an hour or so at the invasion of Normandy, and could take you there and get you out, perhaps..for a fee.
You can imagine time periods becoming trendy, like bars or vacation destinations are now, but why would anyone not go back and setting in the past, using what they know about the future to bend the world into profit for them - or godhood -
In other words, I guess unless you more fully describe the limitations on the time travelers in your world, or the tech they use to get around it's hard to say much, because the problems posed by the tech in the beginning are so paramount.
One thing's for sure, there'd be a bunch of "psychic" folks in little shops all over the city - staying in business somehow....hey wait a minute...
[Answer]
## If you are allowed to bring items back, you can obtain an unlimited amount of any quantity
* Take the most expensive transportable item you can think of, say the crown jewels.
* Go back in time and steal them, then bring them back to the present.
* Now go back to 30 seconds prior to your stealing them, and steal them again, and bring those back. Now you have two sets of crown jewels.
* Repeat *ad infinitum*. Economic collapse ensues.
[Answer]
You have, in effect, created a modified form of [Aorist rod](http://hitchhikers.wikia.com/wiki/Aorist_Rods). Side effects may include large immigration flows of tourists, assassins, and/or entrepreneurs, with the first two proportional to how interesting your local spacetime is, and the last proportional to how cheap it is. In the latter case, supply and demand mean a flood of merchants from various points in the future will buy up all sufficiently inexpensive goods (relative to their own respective presents), trading them for, most likely, information and sufficiently advanced technology.
Due to network effects, there's some incentive to create "market years" where/when all the (peaceful) time travelers meet up to exchange knowledge, goods, and expertise. Due to the fact that time travel costs more the further you go, it's unlikely to be limited to just one market year.
The fact that we are not presently inundated with obvious time travelers suggests that prices here are not particularly low, nor events particularly interesting - market years will likely be the biggest targets. This is possibly due to prior successful actions on the part of more subtle and/or competent time travelers... who may or may not have assassinated or otherwise waylaid the *first* would-be visitors, just before they took their trips. All the groundwork's in place for *someone* to go back, after all, and if you can go back to the year 1917 from the year 2017, *someone else* can probably go back to the year 2017 from the year 2117. And if you're not careful about staying quietly anonymous for your foray into the past, well, they can bribe your bodyguards at any point in their lifetimes.
Thus, all history becomes dull and uninteresting: interesting historical figures (including would-be time travelers intent on making a splash) are quietly assassinated, blackmailed, or otherwise removed; interesting economic anomalies (anything becoming inordinately cheap, or expensive enough to justify bringing back in exchange for the local currency) are similarly dulled through market forces.
[Answer]
### Destroyed art
It would make more sense to go back and fetch [destroyed artworks](https://en.wikipedia.org/wiki/Lost_artworks#Pre-16th_century) than commodities. Show up the day of the fire or whatever and just steal them. The whole world gains a unique piece of art. And if you make a bit of money out of the deal, that's just gravy.
### Crafted goods
The reason why this works is that art is worth more than its components. Often a lot more. Rather than commodities, move crafted goods. Use modern machining to craft goods better than what can be produced in the past. Sell those. You don't even need improved alloys, although taking a steel sword back to the bronze age is likely to provide good returns. A weapon fit for a king (or his bodyguard or best soldier).
### Knowledge is lighter than commodities
Why carry goods? The easiest thing for a time traveler to take back in time is knowledge. It costs no mass, and it carries high value. As an example, it is trivial to look up the locations of [diamond](https://en.wikipedia.org/wiki/Big_Hole) and gold mines. Or oil fields. Buy the land in the past with partners who can manage the actual mining or drilling. Set up a trust that invests the profits for you. Collect the money in the future after compounding has made it much more valuable.
You don't need time travel to carry wealth forward. Compounding value will produce better results. You only need to time travel wealth back.
[Answer]
This is by far not the best way to become wealthy. Since the Industrial Revolution, our total wealth has grown at exponential rates basically continuously.
The best way to increase your wealth would be to simply jump-start human civilization a bit earlier so that you are born later in our history. For instance, you could start the Industrial Revolution a hundred years earlier. Nobody in 1917 had living standards anything like we have now- and the same will be true for 2117. Of course, by the time you return, time travel will be cheaper, so you can go further back and kick-start it earlier, and earlier, and earlier.
Of course, that is small potatoes. You could go back a million years and jump-start humanity's evolution and civilization. We could be hundreds of thousands of years more advanced and prosperous by the time you return. All the money and technology that exists in today's world wouldn't satisfy a child for a day in the poorest nations.
Simply having the world of today but you have a few more dollars in your bank account is thinking far too small for what could be accomplished.
[Answer]
To stick to the originally stated scope of financial trading, I'll choose an
appropriate example, which will apply to lots of different goods with high
value density.
As others have pointed out, the most valuable thing you can bring back is
information (e.g. stock tips), which can also pay off very quickly.
Another good thing to bring back though, especially for a short trip, is
strategic metals (e.g. dysprosium oxide), which typically get cheaper over
time (i.e. more expensive [in the
past](https://www.kitco.com/strategic-metals/)).
Borrow 700oz of dysprosium oxide (2017 value about 181k USD), bring it back
to 2012-01-18 (then valued at 1417k USD), when
[Google](https://www.google.com/finance/historical?q=NASDAQ%3AGOOGL&ei=fyBwWIG1GIqXmAHv8Z_4Bg)
was trading on the
NASDAQ for about 300USD, sell all your Dy, and buy Google.
Leave the shares in your past brokerage account (after all, this is a short
jump).
Today, Google trades at 825USD, so sell your Google shares for roughly
3945k USD.
That's about a 21-fold profit (of almost 4M USD magnitude), which can easily
pay for a very cheap trip of about 5 years\*.
As everyone catches on,
this will have the effect of smoothing out both the Dy price, and the Google
price, since all that Dy is being bought in the present, and dumped in the
past, and Google is being bought up in the past, up to the point where one
can no longer make a profit on such a journey.
Therefore, expect prices of each in the past to nearly approach their modern
levels (allowing some gap due to the cost of transit).
That will mean that this strategy won't be feasible for long, because
arbitrageurs will take much advantage quickly.
Furthermore, expect this same principle to apply to any two goods whose
value ratios change widely over a short span of time.
The large scale economic effects would likely be beneficial, as commodities
would show up where they are most needed.
The above example is essentially like allowing the past to *borrow*
dysprosium oxide from the future, which will bring down the price of magnets
for power generation and electric cars in the past.
"Sure", you may say, "but what about now? Won't that resource consequently
be more expensive now?".
To some extent, yes, but all the Dy that is being sent to the past is being
put to good use where it is most valued. And things that get more valuable
as time goes by (e.g. gold), will be flowing in the other direction, causing
a shortfall in their availability in the time between, resulting in more
mining, etc.
In general, anything that facilitates trade will be an economic advantage to
both parties to the trade.
\*
This is maybe not even the best pair, since a peek at the europium oxide
market shows that it may be an even better bargain today, and dearer
in 2012.
[Answer]
There are scenarios where it can work without changing the history: transport [aluminium spoons and crowns](http://knowledgenuts.com/2014/02/27/the-metal-that-was-once-worth-more-than-gold/), get back the DNA of Michelangelo and Nero - insert a passage of Newton being nagged by a microrobotic mosquito probe; or just fingerprints of past celebrities for collectors.
Speaking of DNA samples of the past: how about female/gynoid agents seducing and collecting genuine reproductive genetic material for those willing to pay enough to have a child of a male celebrity of the history? (maybe it can work for ova as well?) Any ethical conflicts for a story here? On the line of just the empty vanity of the customers, the children are missing the "nurture" side to realize the potential of the "nature"?
[Answer]
I would like to answer the question from the personal view of the trader. I assume the trader want to get rich with a purpose, maybe to live with the amenities of the rich. Then, why not use time-travel to get what you want directly?
Example: Buying status symbol in the "present"
* Get a loan
* Travel back one day with the money or gold
* Buy the status symbol
"What would be the large-scale economic effects?"
The longer time-travel exist the messier the future will get. Paper money will probably be forbidden. Gold will loose its value, if everyone could get it from the past or future. Suppliers maybe produce for customers that will come from the time-travel-past.
Because you can´t create matter, the future could have a shorthand for many article´s. A consequence could be: The rich getting richer and the poor getting poorer.
Example: watch
* buy a watch
* travel back where you never paid for it
* this watch can only exist once in time-space: it disapears in the store the moment you arraive in the past. (like teleporting)
If one assume the previous example for many individuals, than the consequence will be an massive shift in commodities.
There probably will not only be honest time-travel-traders. For example, doing theft or murder and go back when it never happend.
[Answer]
Within the real world, it's easy to describe what can be done with time machines: nothing. Within a literary world, however, the range of actions that can be done with time machines will depend upon what abilities and limitations the author has given them. If the author creates machines which are too powerful, someone who acquires such a machine would be able to render the actions of everyone else irrelevant. Further, if the limitations of time machines are not made clear, readers will have no idea how to judge whether there is ever any real danger, or if the time machine could always come to the rescue.
I would suggest that while establishing the time machine mechanics won't cause the rest of the story to write itself, it will help ensure that certain aspects of the story are likely to make sense. A mechanic I've not seen used, but which I'd invite anyone to try out, would be to have a machine which is limited to sending back information to a pre-determined time, and will only work reliably in cases where the information is used in a manner that would not violate causality. Someone with such a machine might be able to use it to make a lot of money, but would have to be very careful to avoid any actions that might affect the predicted phenomenon. Among other things, such plans would likely have to involve two people--one of whom would have minimal knowledge of what the machine said, despite having a full understanding of the plan, and the other of whom would minimize contact with the outside world (the former person wouldn't have to worry about accidentally changing the future on the basis of information received from it if he doesn't *have* any such information, and the latter person would find it much easier to avoid influencing anything if he minimizes interactions with the outside world.
[Answer]
Depending on your theory of time travel and its ramifications this certainly could cause absolute havoc, in fact if enough travelers are messing with the *same* commodities both forwards and backwards it could actually create shortages of, well imbalances in, the amounts of the very elements that compose those goods. You'd have to be dealing with enormous amounts of traffic over an extended period of time, (if that phrase even means anything in this context) but it could happen.
As a thought you could go back and get the same goods over and over again and profit from them repeatedly under the right set of rules as long as you go back a little further each time and get in "ahead of yourself".
] |
[Question]
[
A magician summons a person to the material world to be their servant. Their body is not made from true atoms per se, but is some kind of force projection.
In most ways though, they act as a person and experience the laws of physics as if they were a normal flesh and blood being. This includes eating, getting sick, excreting, and so forth.
Away from the main projection though, 'matter' that was once part of the host that leaves the body in the form of carbon dioxide, skin flakes, urine or otherwise will disappear on an 'atom' by 'atom' basis without releasing much in the way of energy with a half life of two weeks.
It is widely known (or believed) that after about ten years the human body will have fully replaced every cell within it. However, I have not been able to find out how much of the material that makes up the cells remains.
How many years will it take to ensure that when the magician tires of the projection and aims to dismiss it, it can reasonably be assumed that the projection will survive with their physical and mental facilities intact?
[Answer]
Your former projection will be in for a hard time, even if they've faithfully served their summoner for decades.
Why? The calcium in bone (and more so teeth, especially the enamel) is relatively permanent -- it doesn't get replaced rapidly or frequently. This is why, for instance, Strontium 90 in nuclear fallout is such a problem -- because it replaces calcium deposited in bones and teeth, and is very difficult to remove because those deposits are relatively permanent.
At the least, when the magician dismisses the summoning, the summoned servant will lose the enamel off his teeth, and his bones will become either extremely brittle or cartilaginous (and the connective tissue that's part of a bone is far from sufficient for bone-like rigidity). It's very likely he wouldn't survive the experience; compression of the spine would heavily damage the spinal cord and result in loss of breathing even if the cartilage framework of the ribs is enough to prevent complete collapse of the chest cavity.
Also worth checking [the answer by @Confoundedbybeigefish](https://worldbuilding.stackexchange.com/a/152423/2113) in which he points out that some cells don't get replaced as frequently as others -- or possibly at all -- and they're extremely critical to life. From comments, [parts of the eye are never replaced](https://biology.stackexchange.com/questions/79381/what-is-the-longest-lasting-protein-in-a-human-body), though it probably doesn't matter much if they're blind, if they're also dead...
[Answer]
Even if they survived Zeiss Ikon's way, there's not a hope of surviving this:
The neurons in the brain don't get replaced over this sort of time period. It is widely understood now that new neurons can grow, but when a nerve cell dies, it is gone for good. The nerve cells in your brain today have the same molecules of DNA that they were initially created with.
Other cells, different story, same problem: when a cell replicates its DNA by [mitosis](https://en.wikipedia.org/wiki/Mitosis) to replace old or dying cells, it unzips its DNA, and new nucleotides are synthesized to be the complimentary strand. Errors are fixed (a small percentage), then the strands are zipped up again - approximately half the atoms constituting the DNA in each daughter cell are from the original.
The mitochondrial DNA (the so-called power-houses of all cells except erythrocytes) would be similarly distributed between cells.
**In conclusion:**
The summoned creature’s cells would cease to function without their energy factories and the nucleus giving coherent instructions to the protein factories - probably about the same way as [acute cyanide poisoning](https://en.wikipedia.org/wiki/Cyanide_poisoning#Acute_exposure) (seizures, cardiac arrest, apnea, coma and death), and probably as quick (a few seconds 'till the end).
**Addendum:**
A human lifetime would not be enough time for atomic replacement to occur that would enable survival. Of course, it might be possible to design a species that could withstand this treatment, but not within the scope of the question.
[Answer]
I'm afraid it's even worse than the other answers say. They talk about what happens if molecules suddenly go missing, but we're talking about atoms here. You won't lose a whole DNA molecule, you'll lose some of the atoms contained in that molecule, and the remaining atoms are likely to become highly toxic [free radicals](https://www.medicalnewstoday.com/articles/318652.php). It's instant death no matter how much time has passed, because it only takes a tiny proportion of your atoms going missing for the toxicity to kill you.
[Answer]
The answer to this depends on how whether or not your "force-body" detects that it has a problem.
Most of the answers have given cellular replacement rates and mentioned some cells don't get replaced, or that there would be problems with bones, etc...
However, this is all under normal homeostasis conditions. In most cases, there isn't a magic clock that tells your body to replace cells; your body replaces cells when it detects damage. The idea that the body completely replaces all of its cells on average every 7 years is mostly correct, but that's not due to a special clock; it's just on average how long cells last. The body doesn't replace parts that don't break down. Fast reproducing cells are in areas where they're likely to get damaged quickly and need constant replacement, slow reproducing cells are in areas where they don't get damaged. This is why your skin and digestive tract get replaced a lot; they're exposed to the outside world. Your brain isn't, so your neurons don't accumulate damage as quickly and thus don't need to be replaced.
But even cells that aren't replaced have to rebuild themselves and fix damaged parts. Entropy demands this. There are a lot of chemical reactions going on in a cell, and those reactions can damage the cellular machinery. Your neurons may not be replaced by new neurons, but the ones you have are constantly replacing and fixing their constituent parts (read: atoms and molecules).
All of this bodily restructuring is controlled through complex chemical signalling mechanisms. Cells detect whether or not they're damaged, and attempt repairs. If the cell is too damaged to repair itself, it decides to die, allowing itself to be replaced by a new cell. These are the processes of catabolism (breaking down) and anabolism (building up), and they occur in every part of the body without exception. Even your bones are constantly being broken down by osteoclasts and rebuilt by osteoblasts in response to signalling from the thyroid and parathyroid.
Now, the question is whether or not your cells can detect that the "force-atoms" aren't real and need to be replaced. This is actually where things can get very interesting from a story point of view.
If your force-atoms don't behave exactly like real atoms, there is a chance they won't break down at all, in which case your force-body will not be subject to the chemical stresses that drive homeostasis in the first place. Cells won't age and won't break down, and your force-person will be immortal. They also won't replace *any* atoms and will only rely on food/water for energy. At best you have a person full of ATP and not much else, maybe some real water.
Assuming your force-atoms are subject to the same kind of entropy and uncertainty as real atoms, we could reasonably expect that your force-person will replace itself at the same rate as a fully physical person. In this case, your force-body will very slowly replace parts of itself, but never a complete whole. This is because the parts that normally won't break down won't break down, and so will remain mostly composed of force-atoms. But, it is conceivable that on a long enough timescale, all of the atoms would be replaced. Unfortunately, this timescale is likely longer than an average human lifespan.
However, as I mentioned before, homeostasis is actively regulated. The body understands what's broken and what needs replacing, and will do whatever it must to maintain that balance. If your body detects that the force atoms aren't real, and thus "damage," it can ramp itself up and replace them rather rapidly. Cells will see their force atoms as not real and seek to replace them. Some cells will be replaced entirely, etc... Even neurons would eventually repair themselves in this case by replacing their machinery. This is essentially how wound healing works.
There is a problem with this though: a cell that has sustained irreparable damage will commit suicide through apoptosis, and a cell detecting that all of its atoms are completely fake may decide it is too damaged to repair.
In this case, your force-person dies a rather slow and painful death over several weeks in a manner that would resemble radiation poisoning. Not a fun way to go.
The key here, if you want your force person to completely replace their atoms, is to ensure that the cells detect damage that is repairable and attempt to do so, with them having a preference for real atoms and molecules over force-atoms. In this case, your force-person would replace themselves rather quickly, probably in less than a year, if they were well fed with a highly nutritious diet. Their force-bodies would also suffer from an insatiable hunger at all times as the body desperately signaled to increase nutrient intake in order to repair itself.
As an aside, there are also some deeper questions you'll want to think about. A human being isn't just all of the cells that make that human up, but rather a collection of human cells and commensal flora and fauna: a bacteriome. In fact, numbers-wise you are made up more of your bacteria than your actual human cells. These bacteria can't survive without you, nor you without them. They live in your gut and process certain foods into vitamins for you, they live on your skin and keep you protected from pathogens, they're even involved in determining your weight. They are you, and also aren't you. Is the bacteriome also made up of force-atoms, or are they real living bacteria?
[Answer]
While our cells die and new are created in their place we do not just excrete them - they are reused, especially molecules that are scarce as it would be highly inefficient to just throw them away.
After a cell dies, it allows itself to be caught and digested by a macrophage in its lysosome (a kind of acidic cell stomach). <https://www.sciencedirect.com/science/article/pii/S0092867410001297>
I dont have no idea what is the probability the digested cell parts are excreted but it does not make much of a sense to remove the DNA nucleotides that are recycled from body. And as Mike Scott said in his answer, the damages that would occur in DNA would be catastrophic.
So it seems unlikely even an almost complete replacement would occur over during a persons lifetime...
[Answer]
Survival is impossible.
Yes, the body turns over the atoms in it, at different rates for different parts of the body. The problem is that this is not a first-in-first-out process.
Calcium has been singled out in other answers, lets look a bit more carefully. Suppose it has 100% turnover in 10 years. Does that mean all the original calcium is gone? No, it is a random process. You actually will have about half of the original calcium present. In 100 years you'll still have about .1%.
However, calcium isn't the biggest problem. Rather, the weak point is DNA. The turnover is very low and it's very sensitive to damage. You can **temporarily** survive this damage as the DNA isn't used directly, but you can't make new cells. We already have a partial model of what happens in this case: Look at what happens with a lethal radiation dose.
] |
[Question]
[
We all know that food spoils if left untreated by some form of preservation. Different foods spoil at different rates, of course.
Let's say Dracula stumbles across a fresh corpse. (For the sake of argument, assume the person died of natural causes.) How long will it be safe and effective for a vampire like him to drink the blood of that body?
(See [this question](https://worldbuilding.stackexchange.com/questions/32502/which-is-better-for-vampires-fresh-blood-or-frozen) for a similar question about the nutrition of preserved blood. I'm instead asking about *unpreserved* blood.)
[Answer]
For a starting point, consider the meat aisle at the grocery store. In it you'll find roasts, steaks, and other chunks of red meat. [This government food-safety site](https://www.foodsafety.gov/blog/meatinrefrig.html) says that such meat can be kept in the refrigerator (40 deg F) for 3-5 days. That's for meat that's already been cut up, drained of most of its blood,1 and packaged for individual sale. Before that, it could have been kept for [a couple weeks or more](https://www.quora.com/How-long-after-a-cow-is-slaughtered-does-its-meat-reach-supermarkets). That's just some context; *stuff that came from dead livestock*, in general, can be safe for rather a while.
That's for meat that people are trying to keep safe. But that's not Dracula's case; he's not raising livestock. So while bodies kept at the right temperature could supply some blood for a couple weeks, it's bounded by how long a body *not* kept at the right temperature can sit around before the blood is dangerous to consume. We also have to consider coagulation -- how long until the blood isn't sippable any more because it's clotted?
Spoilage due to bacterial infection in the blood can begin [within hours](https://en.wikipedia.org/wiki/Meat_spoilage#Infection), but appears to come from two main sources: bacteria in the intestine at the time of slaughter, and infection caused by the slaughtering process. Indeed, one government agency has [special guidelines](http://www.inspection.gc.ca/food/meat-and-poultry-products/manual-of-procedures/chapter-17/eng/1367723343665/1367723573062?chap=7) for collecting blood for human consumption (17.6.3.1.1 ). Dracula should select for bodies that died intact, not roadkill or ones that died from wounds, to minimize risk of infection.
As for coagulation, if there has been an opening (like an incision), blood coagulates quickly after death (within minutes). If there is no wound, however, [blood remains liquid for several days after death](http://gira.cadouarn.pagesperso-orange.fr/english/medicine/hematology.htm). (See also the [Wikipedia article on lividity](https://en.wikipedia.org/wiki/Livor_mortis).) That's true even at room temperature. (Freezing does bad things in the coagulation department, but that isn't Dracula's situation.)
Putting all this together, an intact body with no special precautions will contain liquid blood for several days. If it is kept cool during that time it should be safe on the infection front. (Plus, maybe vampires don't worry about infections; consult the physiology specifications for your particular model of vampire.) If he cares about blood-borne infection, Dracula will do best in cooler climates, whether natural or man-made (morgues).
1 I'm going to draw on an unusual source for this: Jewish dietary law. There is a religious prohibition against consuming blood. When an animal is slaughtered its blood is drained in the usual way (just as it is for other slaughter), but Jewish law requires an additional process of salting the meat to draw out more of the blood. It's of course possible that this is completely redundant and what the rabbis who instituted this were seeing wasn't blood but water with myoglobin (thank you Selenog for teaching me about myoglobin in meat). But I've heard a lot of arguments over the years about how such-and-such practice shouldn't be required any more because science, and I have never heard an argument against this one.
[Answer]
It is Not (for some mythologies)
It should be noted that the blood of the dead is poison to vampires in a number of mythologies and stories.
For example in interview with a vampire.
>
> ! Claudia poisons Lestat by tricking him into drinking blood of the dead.
> "She tricks him into drinking the blood of twin boys she killed by overdosing them with laudanum, knowing that blood from a corpse is fatal to vampires. This weakens him, and she slits his throat. Claudia and Louis dump Lestat's body in a swamp and the two plan a voyage to Europe." --<https://en.wikipedia.org/wiki/Interview_with_the_Vampire_(film)>
>
>
>
And in Supernatural the Winchester Brothers use blood of the dead against vampires.
[Answer]
Given you tagged this as a 'vampire' question, I'll assume you're a friend of mine and we're chatting over tea ^\_^ (actual tea, not blood in a teacup)
You have to consider what the vampire is drinking the blood for. Yes, TrEs-2b is right on the medical facts (I didn't fact check, but it sounds about right). However, this isn't just about the medical, this is about the mythos of the vampires you're talking about.
Now, seeing as [our vampires are different](http://tvtropes.org/pmwiki/pmwiki.php/Main/OurVampiresAreDifferent) I will assume you are going to change certain things to make them make sense for what you want them to represent. If it's a magical thing, and they are 'feeding' off people for (insert reason here), then you'll want them to be alive as they feed. If you want them to show you the 'lawyer stereotype', where "they'll still screw you after you're dead", then go with the medical maximum (TrEs suggests about half an hour, but keep it shorter because you don't want 'oops moments'). Or if they are meant to represent an undying link to the past, then it really doesn't matter -- you can have them drink week old, dried blood, just give them some kind of [handwavium](http://tvtropes.org/pmwiki/pmwiki.php/Main/AppliedPhlebotinum) to make the blood 'fresh from the vein'. Because it's about their preservation, not about the blood itself.
The point is, you need to focus on what your vampires represent, not what their limitations are. Yes, you need to know the medical/scientific limitations, but limitations can be worked around. Not only because this is *the* **evolutionary concept**, but because this is your creation.
[Answer]
Dracula and his ilk are supernatural monsters. Sorry, if that's offensive, but how else can you describe someone who is an undead bloodsucker. So it is doubtful if health concerns such as infection will harm vampires. Therefore, the most likely limit Dracula faces is how long blood remains fluid, so he can siphon blood from a cadaver.
Research into the topic of blood coagulation proved harder than expected. Certainly a few hours after death is likely, but longer times may be possible. Monica Cellio has suggested longer times, but I am not confident about whether this is either right or wrong. The information isn't readily found or what can be found is difficult to decode into something useful for this question.
Considering that vampires have a tendency to prey on living victims this does suggest that they may be the kind of predator that preferentially attacks live prey. In which case, the time would be zero. Once dead, someone is no longer vampire prey.
The other alternative is rather yucky. Perhaps because vampires are supernatural monsters, their supernatural powers extend to draining blood from even the most dead of the deceased. This means the long dead, the sort who get put into the ground. Basically the ones who haven't started to decompose yet. Considering vampires rest in graveyards that receive regular supplies of the newly dead, so they might preferentially feed on these new corpses. It would save going into town and molesting live prey. There will always bring the blowback of people wanting to stick stakes in the hearts of the vampires.
[Answer]
Well, basically you've got two forms of Vampires when it comes to blood: Ones who derive sustenance only from blood, and those who only drink blood because it contains the life force of the victim.
The actual blood would be divided into Plasma and Blood Cells. Plasma would last until it dries out, because it is basically a bunch of dissolved nutrients. Blood cells live 60-120 days in the body, but the actual cells would live until they exhausted all of the glucose in the blood stream (don't need oxygen). If other organs are to be judged by, anywhere from 4-48 hours.
If you're talking life force, that would be anywhere from the time of death to 3 days after (based on Hebrew resurrection lore). Depends on the system.
[Answer]
Depends probably on vampire taste and physiology, since many novels assume vampires have great smell, than probably they only like blood from alive meals **because of the smell of adrenaline/fear**.
The main point is that animals' blood is good for human usage after several hours (depends on temperature, in a hot summer I would assume half-hour, while in winter is probably fine up to 8 hours). But that is based on human physiology. When you look deeper you will find that blood is made of several different compounds, each one taking a different time to decay according to the temperature/light/pressure conditions. Wich compounds do vampire need to consume?
Maybe blood temperature plays a role, since body temperature decrease by 1.5 degrees each our, then maybe a vampire cannot consume blood cooler than 33 degrees, so it has to drink it after 2 hours from the death, and probably cannot drink blood from alive targets in hypotermy
[Answer]
I imagine as long as it would take for blood to dry, half an hour-hour. A study published in the International Journal of Legal Medicine reported that a blood drop on a hard surface in a typical indoor setting at 20 degrees Celsius is completely dry in 60 minutes. Increasing the temperature to 24 degrees Celsius reduces the drying time to only 30 minutes.
For Dummies says that deoxygenated blood enters the right atrium of the heart during circulation, at which point it is forced through the pulmonary valve and into the pulmonary artery. Here, the deoxygenated blood travels through the pulmonary artery to the lungs where it receives oxygen and becomes oxygenated blood again. From here, the process starts all over again, and the oxygenated blood leaves the pulmonary artery to bring oxygen to the cell membranes once more.
[Answer]
I am assuming that vampires can consume blood off a dead person (which is not always the case as mentioned in user3559247's answer). It seems likely (to me at least) that vampires do not actually suck the blood out entirely by themselves; instead they would partly rely on the heart to pump the blood out for them. A human heart can keep pumping blood for a maximum of a few minutes after death, for example until it fails due to lack of oxygen.
Of course the whole things depends on how you define death. With the heart still beating, some might say that a person is not dead yet. But it seems reasonable to say that a person whose brain is smashed beyond any repair is dead, even if the heart would still keep beating. From such a corpse a vampire could quite easily suck blood until the heart stops beating.
There is another thing to consider also, and that is blood clotting. It is probably safe to assume that a vampire cannot consume coagulated blood. I couldn't find any sources on how long it takes for blood to clot after death; but it does depend on the type of damage on the corpse. If there is plenty of damage to the blood vessels, the blood clots quite rapidly (in a matter of minutes!) at least around the damaged portions. Without damage, maybe a few days until the blood stops being a liquid?
As a final note, in the time frame between the stopping of the heart and blood clotting, the vampire could use gravity to get the blood out of the corpse, as a butcher does with an animal carcass. But note that butchers usually drain the blood immediately after death or stunning of the animal, as the blood comes out much easier with the heart still pumping.
[Answer]
You could use forensic science data on post-mortem lividity (pooling of blood in the lower portions of the body, and its loss of oxygen) to set a time scale. [This website](http://www.forensicpathologyonline.com/e-book/post-mortem-changes/post-mortem-hypostasis) say that the process is well developed in 4 hours after death and a its maximum at 6 to 12 hours.
Or this website says that after a few hours [the blood becomes fixed in place](http://www.deathreference.com/Py-Se/Rigor-Mortis-and-Other-Postmortem-Changes.html). So Dracula would have to chomp and chew rather than sip and suck to get a meal!
[Answer]
A talented, experienced person (like a butcher or Dexter) could do quite well at draining a fresh body.
Let's say your Dracula is one of those and he stumbles across a freshly killed mortal within minutes (less than 30 minutes) of the unfortunate's demise. Dracula may, depending on time and equipment, be able to drain as many as 10 pints (on average) of blood from the deceased. That blood, if kept the way the American Red Cross keeps it (refrigerated and in an airtight seal), can last for as long as forty-two days.
] |
[Question]
[
Consider a future soldier with access to the technological augmentation indicated below, and for whom it is reasonable to believe he would spend (while deployed) at least 18 hours a day attached to the augmentation.
*Vision, by way of a wholly transparent plate wrapping around the eyes and including periphery, displaying:*
* Enhanced resolution of surrounding terrain.
* Full, clear day vision regardless the actual conditions (storms, night, etc).
* Automatic identification including on-call background of people and items in the field of vision.
* Automatic threat analysis including trusted friend-foe identification.
*Audio*
* Configurable background noise masking.
* Automatic volume normalization.
* Configurable critical noise enhancement.
**Question: What adverse effects or any of withdrawl could a soldier expect after prolonged exposure to this augmented reality?**
[Answer]
Just going by the features themselves it would mostly be soreness and an acclimatisation period after coming in and out of gear. Chances are, your ability to see in the dark, cope with sudden bright light and to deal with loud noise, hear quiet noises and deal with a wide band of volume will be reduced for a while. However, I tremble at how much this could exacerbate the psychological trauma that can come with active service. Imagine how it would be for a soldier who comes out of long term deployment in an actual war with some measure of PTSD.
While wearing the gear you can see in the dark, an explosion is just about as loud as it would be in the cinema and your HUD always tells you who is friend or foe. Now you come out of deployment, possibly showing symptoms like hyper-vigilance, insomnia and an exaggerated response to being startled. Suddenly you can't see properly anymore. Every shadow is ten times as scary because you're not used to being unable to see what's in it. The night has turned into a fog of war. Even just a passing motorcycle sounds louder than an artillery shell.
Worst of all, you can't trust anyone anymore. The helpful friend indicator is gone - everyone is just an unknown to you. Are they enemies? Can you ever know? Should you take measures to keep safe?
Maybe you should put on the gear again. Just to have a look if everything is in order. Actually, it's much more comfortable to wear than you first felt back in basic training. There's no reason to really take it off, is there? People are giving you strange looks already, can't get much worse, can it?
And god have mercy on anyone who registers red.
[Answer]
**Sensory overload.**
In the HUD only things that mattered called for attention. In the civilian world nothing that matters has any tags or information and everything that doesn't does. I've probably ignored 100 advertisements today, but I have no idea because I habitually ignore them. This would be a major problem for soldiers trained to trust a HUD.
"That man has a gun." --Thanks computer.
vs
"you need a new car." --no. I have a fine...
"you need a cold drink." --I don't th...
"you need a video game" --arghh! Wait. Where'd my kid go?
[Answer]
I'd expect soldiers top have similar effects to astronauts being used to zero gravity after coming back to earth, basically, expecting the same effects when not using the AR:
* Not understanding why he can't see in the dark
* Being unable to recognize team members without the identification box
* Being too disoriented by the background noise
* Expecting to hear footsteps in the rain 100 meters away
* Loud noises can cause headaches
* Can't determine the source of the fire by sound, not hearing bullets whizzing by.
[Answer]
The augmentation is primarily sensory. The heightened sense of perception in a combat zone will induce a greater probability of soldiers suffering post-traumatic stress disorder (PTSD).
During deployment, for example, on patrol and especially they are likely to suffer from headaches and earaches. Firstly, due to wearing the augmentation technology, and secondly, due to the sensory overload they will experience.
However, since these are future soldiers, it is possible the augmentation will be able to adjust itself to meet the comfort needs of its users. Sufficiently light and non-obtrusive devices that do not induce sensory overload could make the soldiers' lot a happier one.
But the risk of PTSD will remain as the soldiers will still experience a heightened perception of combat and all its gruesome consequences in intimate detail.
[Answer]
Frustration would probably be the worst after-effect of extended exposure to augmented reality. Not being able to see as clearly as you are used to in twilight conditions, or being unable to make out someone's mumbled speech.
You might also find yourself whispering to yourself; sub-audibly requesting armor features such as facial recognition and tactical information. People might start thinking that you're a little bit crazy.
[Answer]
The soldiers would experience the similar problems to those of ordinary soldiers except that any physical injury would be absent.
Although any soldier waring the VR would know intellectually that he or she was physically safe, the subconscious reactive parts of the brain would not, it would be fooled by the VR. So it would still be possible to suffer from a range of mental problems caused by stress.
There is also the possibility of some very unpleasant visual experiences if the enemy and/or civilians get mixed up with high explosives. So post-traumatic stress syndrome would still be a problem.
[Answer]
Regular withdrawal syndromes aside (headache, tunnel vision etc.), they would likely experience visions of still wearing the augment.
Seeing threat indicators where there are none
Feeling the rain and wind of bad weather conditions while sitting on a warm beach
Just like ghost pain in lost limbs, the brain tries to make up for what it has lost. Especially when the brain gets tired and falls back on routine.
[Answer]
Aside from some possible physical discomfort due to eye strain, there's no reason to expect "withdrawal" any more than people spending a day gaming with much of the features you indicate would suddenly suffer symptoms going out and looking at the world where everyone doesn't have convenient tags over their heads.
[Answer]
I can give an alternative view answer based on personal (well, near-personal) experiance.
Someone close to me is a teacher, and one of the kids they teach is a child who went nearly completely deaf suddenly over christmas last year. Child X (as we should call them) is extremely averse to loud noises at present and detests going out to play at break and lunch time, because X is not used to filtering the noise out. X would prefer to stay inside in the quiet, as X is used to doing when X is at home, where they often go without their hearing aids. ITs got to the point where he'll be "naughty" just so he doesn't have to go outside.
So in your story, soldiers have augmented senses that allow them to see in the dark, enhance what they want to hear, and filter what they don't.
Suddenly all that is taken away. Noises that the augment buddy would remove, suddenly don't go away. That noisy hubbub in the shopping centre becomes deafening, simultaneously whilst they are nearly deaf to noises they *want* to hear. The sunlight as they come out of a dark room on a summers day blinds them momentarily.
Functionally, anything other than allowing them to wean off would create massive PTSD and mental health issues for the soldiers, particularly given the paranoia of no longer easily seeing "friend" vs "Foe". Assuming that such augments are not just military tech, it would likely result in specialist doctors who adjust the sensitivity of the tech to ease them back into daily life. As in many treatments, not all soldiers may react well to this. Some may continue to need low light vision, others the filtering senses. This would be an important point - **not everybody reacts in the same way to trauma or recovers in the same way.**
] |
[Question]
[
I'm writing a speculative fiction story that includes superhumans. The focus is on individual characters and their daily lives, and I'm trying to maintain some consistency by not throwing all the laws of physics out the window. However, this creates some problems in the daily life of these individuals - where does their super-energy come from, given that they appear to eat a normal amount of food?
For example, a superhuman with super-strength is able to lift heavy objects. This is fine according to the laws of thermodynamics, as long as a proper amount of energy is used to perform it. To lift a 15,000kg semi 2 meters off the ground, my superhuman needs to contribute a minimum of 60 kcal. In a typical day, this character might perform an action like this 50 times, for an additional energy expenditure of 3,000 kcal - that's more than double the normal energy expenditure of a similar human. On intensive days, this energy cost might be closer to 20,000 kcal.
How can I justify this discrepancy between the energy my superhumans expend and the energy that they consume, assuming they eat a normal amount of normal food? **Specifically, how could a superhuman obtain the 20,000 kcal expended in an intensive hero day without eating proportionally more?**
---
Shoutout to the [Sandbox](https://worldbuilding.meta.stackexchange.com/questions/6168/sandbox-for-proposed-questions) for helping me develop this question!
[Answer]
**Improved efficiency!**
Lifted from <https://physics.stackexchange.com/questions/46788/how-efficient-is-the-human-body>
>
> The MET (Metabolic Equivalent Task) readout on your gym equipment is
> your body doing 1Kcal/kg/h = 4184 J/kg/h and can be reasonably
> accurately measured by how much oxygen a test victim uses.
>
>
> Sitting still is roughly 1 met and cycling at 100 Watts is around 5.5
> Mets.
>
>
> So taking a man of 75kg, cycling at 100Watts (100J/s) he is having to
> do 5.5 \* 4184 \* 75 / 3600s = 480Watts so an efficency of 20%
>
>
> Remember though that the person is spending 80-100Watts just staying
> alive doing nothing - unlike your car. There is an interesting
> experimental fit to how much energy you need to just stay alive,
> calculated about 100 years ago, the Harris-Benedict equation
>
>
>
If your heroes are more efficient at energy conversion this can explain why they can get double or triple the energy from their food.
Also
**Fat heroes.**
You can store a lot of energy in your body as fat and that is what your heroes do, with repeated trips to Wendys. I can vouch for that method. By virtue of their superhumanism, they metabolize that fat very rapidly to perform feats requiring great energy expenditures. Note: if their metabolism works normally mobilizing that much energy really fast would entail 3 other things.
1: Rapid respiration. They are burning that fat to CO2. They will need oxygen and lots of it. The might carry a little tank and portable mask, like Dennis Hopper in Blue Velvet. Or they might just breathe really fast. Or both.
2: Water production. CHO + O2 -> CO2 + H2O + energy. The water has to go somewhere. I propose they could sweat it out with supersweat glands.
3: Heat. Entropy takes its tax and that means a fraction of the energy goes to heat. These heroes will heat up when they do their stuff. Fortunately panting hard and sweating profusely will take care of most of that in the customary ways. Some heroes might augment onboard cooling abilities by putting ice in their pants before particularly heroic maneuvers.
Your obese, hungry, efficient heroes will be red faced, soaked with sweat and breathing hard when they do their super moves. They will look like Turkish power lifters. I say that is a fine change from the cool and composed thing you usually see!
[Answer]
**Your heroes are nuclear**
Not exactly nuclear reactors, but if you're going to hand wave to the point where they are able to channel energy into superhuman acts, you can almost realistically justify that energy supply as coming directly from matter.
Ignoring small potatoes like potential chemical energy (our biological power source), go straight for the roughly 9x10^16 joules per kilogram (21.5 trillion kilocalories) that relativity suggests is in resting mass itself. If your heroes convert mass directly to energy, they have a basically unlimited source.
The only question at that point is why they need to continue eating, since a single meal would power endless exploits.
(Thanks goes to the Mass-energy equivalence Wikipedia page.)
[Answer]
The classic canonical energy source for Superman was "our yellow sun" and though this seems ludicrous in some senses today, you could crib from this in some interesting variants:
***1) Photosynthesis:*** your supers actually generate chemical energy and store it hyper-efficiently in special cellular ATP bins, which standard humans don't have, not to mention our not being able to directly convert light into chemical energy.
***2) Magneto-electrical:*** your supers have ***radically*** different cellular biochemistry as well as cellular physiology from standard humans, with naturally filtered ferromagnetic particles forming an essential part of their super metabolisms; as a result they generate electrical energy as they move through the Earth's magnetic field via induction, and the carbon nanotubes woven into their cellular mytochondria focus and transport this energy to per-cell electrical storage stacks - this energy is stored to be released in high bursts like a natural capacitor, and is used to catalyze their already hyper-efficient metabolisms at the cellular level. Some supers can store and channel this energy at a system level also - hence Ororo / Storm style lightning throwers.
***3) Cosmology-physics 01:*** your supers basic matter are composed of particles/strings which are unusually vibrationally aligned in several of the more obscure of our 11 dimensions such that they gain energy from moving across certain by us unobserved symmetry-breaks (sort of like getting and releasing potential energy from climbing and jumping off boulders) but they must pay careful attention to direction and orientation of these breaks as they move through them, as they could make a mistake and subtract energy if incautious.
***4) Cosmology-physics 02:*** your supers have a metabolic constituent which is en masse quantum entangled with regions of higher-energy particles which occur inside stars (hence the Superman - yellow sun misunderstanding of the past) and which provide them unceasing energy throughout their lives as long as the star to which they are personally aligned continues to perform as typical for a main sequence star. In fact, if they ***don't*** find an outlet for all this extra energy, they will spontaneously combust - hence both the 'drive' they all seem to have for performing superfeats all the darn time and the rash of unexplained spontaneous combustion deaths in the 1970's - lazy, stoned supers not getting they supergame on.
[Answer]
## Super Dense Foods
In another [world building question we dealt with magical bread](https://worldbuilding.stackexchange.com/questions/56044/lembas-bread-2000-calories-per-bite) that contained 2,000 Kcals per bite. The Most accepted answers states this bread is:
>
> nearly as dense as granite
>
>
>
However your super human has super human strength and super human bite pressure. He can chew this bad boy up like a cold cereal!
Considering you need 20,000 Kcals you only need 10cm^3 of the stuff for a whole day of super human saving!
[Answer]
Your superheroes may rely on [Ch'i / Qi / Ki](https://en.wikipedia.org/wiki/Qi) or any variants of the same principle (like "the Force" in star wars). It could explain the difference in energy. The superheroes are able to harvest energy from life itself. *Qi* by itself is not proven by science (from link above):
>
> Qi is a pseudoscientific, unverified concept, which has never been
> directly observed, and is unrelated to the concept of energy used in
> science (vital energy is itself an abandoned scientific notion).
>
>
>
However, eastern spiritual streams and religions strongly believe in *Qi*. For instance an introduction can be found on [this site](https://www.qienergyexercises.com/what-is-qi-energy.htm).
>
> Qi is the Chinese term for life energy, or life spirit, a vital force that flows through all living things. It is an essential part of acupuncture, qigong, reiki, and the martial arts of the East, among other things. There is no mystery to it.
>
>
>
[Dragon ball](http://dragonball.wikia.com/wiki/Ki) series used this to overcome the same problem:
>
> Because there are physical limits to the strength of the body itself,
> it is necessary to increase one's ki to overcome this barrier and
> become stronger.
>
>
>
[Answer]
**Alternate energy sources**:
Obviously, for a world to have superheroes must needs break at least some of our assumed laws of physics. I think the cleanest resolution would be for the distinguishing factor of superhumans to be the access to some *other* form of energy not normally accounted for.
One of my favorite Asamov stories, [The Gods Themselves](https://en.wikipedia.org/wiki/The_Gods_Themselves) includes the concept of exploiting access to a parallel dimension, in which physics works subtly differently than in ours, to derive massive amounts of energy.
Imagine some quirk of quantum mechanics which allows certain conscious beings to tap into some other dimension at an unconscious, subatomic level. They would be channeling what amounts to a difference potential in atomic forces. In fact, if you posit infinite parallel worlds, the variations in super powers could be due to the variations in universal laws.
That way, most of the physics in your world work the same as what we normally assume. And, there wouldn't necessarily be any obvious difference in biology (which has often been bothersome to me in certain Superhero world-concepts; evolution doesn't work like that dammit).
[Answer]
## They can freely manipulate fields
These superhumans have developed an organ controlled by their brain that lets them manipulate different [fields](https://en.wikipedia.org/wiki/Field_%28physics%29) ([electromagnetic](https://en.wikipedia.org/wiki/Electromagnetic_field), [gravitational](https://en.wikipedia.org/wiki/Gravitational_field), [higgs?](https://en.wikipedia.org/wiki/Higgs_boson#Higgs_field), etc.) Each individual can manipulate each field differently and so their powers manifest differently. The food they eat is used for regular body functions including this new organ, so they may eat an athlete's worth of food as a result of using their powers. The power itself is a result of which field(s) they can manipulate and how they're manipulated, so their skills also require a bit of brain power and practice to get right.
Since there may be a multitude of different kinds of powers, here's a quick list of how some powers might be explained in this scenario:
* super strength: anti gravity (weaken gravitational fields) against external objects + EM to strengthen skeletal system
* flight: anti gravity against self
* lightning/energy blasts: manipulate EM fields to produce charges or focus photons
* invisibility: (EM) bend photons around an object
* teleportation: manipulate gravitational fields to bend space between two distant locations (free time travel?)
* regeneration: this one's tricky. Cells could be forced to replicate quickly via chemical signals (no field changes required) but this would require a lot of energy (and concentration?). Another option might be to use gravitational fields to locally reverse time on parts of the body, or the body as a whole. Unintended side effect: the individual forgets what happened before the incident after full-body recovery.
* super speed: another tricky one. Perhaps the individual makes him or herself lighter and/or manipulates spacetime so that everything around them slows down.
Overall, using this method you can minimize energy expenditures while explaining a wide variety of super powers.
[Answer]
**First of all, you won't get a science-based answer simply because things don't work that way in the real world.** "Calories in = calories out" is one way to look at it; conservation of mass and energy is another.
You're effectively looking for a plausible-sounding pseudo-science explanation, at most, regardless of whether you want to admit it. That said, it is entirely up to you to decide how far you drift from respectable scientific ideas.
**1. Explain only what you need.** Unless the mechanism behind a superpower is necessary to develop plot or character, don't discuss it. This is a good general rule in writing.
**2. Convert mass to energy.** A minuscule amount of mass creates an enormous amount of energy---from a human perspective. If your superhumans are somehow doing this, they are capable of tremendous feats with little "food" consumption.
**3. Sci-fi with clear knowledge.** You can make things sound science-based without actually being scientific at all. E.g., you start with "Several new metabolic processes have been identified in superhumans which allow..." and then explain briefly how they can extract more usable calories from food, engage in some sort of photosynthesis, etc.
(I remember some science speculation about ATP with extra phosphoryl groups, for instance, but that's more like a bigger battery than a bigger generator. Plus, it probably didn't evolve in any known creature for a reason.)
**4. Sci-fi with limited knowledge.** Contemporary science can detect fields, energy waves, etc around these superhumans, but it cannot explain how their abilities function. There are always unexplained phenomena at the edge of science, so this isn't anything new. You can make the phenomena seem more science-based by mentioning any measurable effects, which scientists would observe and investigate.
**5. Quasi-magical.** You said you didn't want this, so I mention it only to complete the spectrum. Sci-fi encroaches here often anyway. Most people have zero understanding of quantum theory and string theory. You could make up almost anything, and most readers would roll with it. This may irritate physicists and pretentious intellectuals because it flies in the face of established science, but a non-starving Superman flies in the face of established science to begin with.
[Answer]
**Higher efficiency:** Human muscles only have ~30% efficiency. If your superhumans have almost 100% efficiency they could do three times the work without needing more food.
**Lower resting metabolism**: Humans need ~1500kcal per day just to stay warm and alive. Your superhumans could have a lower body temperature, better insulation, hibernate during sleep (and sleep a lot) or anything else to reduce this requirement drastically.
A normal human male burns about ~2500kcal when running a marathon. With the above modifications your superhumans could run more than two marathons without needing extra food (compared to normal, sedentary humans) on that day.
[Answer]
The figures you put in your question are not so impressive...
Consider a [sumo wrestler](https://www.lingualift.com/blog/what-sumo-eat-wrestlers-diet/):
>
> The ideal weight for a sumo wrestler is anything from 400 to 600 pounds. This means that it takes not only strength and flexibility to be a sumo—it also takes the right diet. Eating is an essential part of their training.
>
>
> A typical sumo wrestler eats a daily diet of 20,000 calories, which is pretty astounding when you consider that the recommended daily intake for a healthy, active male is 2,500. They eat 10 times what a normal male eats and all of it’s done in two massive 10,000-calorie meals.
>
>
>
Your superhero is basically a slim sumo wrestler in Lycra pants...
>
> Here is a typical sumo wrestler daily eating schedule:
>
>
> **Skip breakfast**
>
>
> A sumo wrestler’s day starts at four or five o’clock in the morning with training and exercise. Surprisingly, breakfast is not served. Skipping breakfast and working out instead slows down the wrestler’s metabolism, so they usually don’t eat until around 11am. It also gets them hungry enough for that 10,000-calorie lunch.
>
>
> **Bulk load**
>
>
> The main dish that sumo wrestlers eat is a stew called chankonabe (ちゃんこ鍋). It sounds a little like ‘chunk nabe,’ which is somehow oddly appropriate. This is a stew filled with fish, vegetables, meat and tofu. Nabe (鍋) is a traditional Japanese stew, but chankonabe is the supersized version, stuffed full of extra everything for the sole purpose of providing calories. To complement their mighty meal, sumo wrestlers eat around 5–10 bowls of rice and copious amounts of beer, required for empty calories. A healthy rikishi (力士, sumo wrestler) may down as many as 6 pints during the midday meal.
>
>
> **Take a siesta**
>
>
> After lunch, there’s one more essential bit of training—the nap. How could you not pass out after a meal like that? Sumo wrestlers take a siesta for as long as 4 hours after lunch, in order to slow down their metabolism and add everything they just ate to their girth.
>
>
> **Dinner and lights out**
>
>
> At the end of the day, sumo wrestlers eat another massive meal and call it a night. While
> they sleep, the day’s protein and calories work their magic and they wake up in the early
> morning ready to smash their bodies against each other.
>
>
>
[Answer]
# Organic Cold Fusion
Cells or an organ takes water and can detect if it is [heavy water](https://en.wikipedia.org/wiki/Heavy_water). If it is it breaks it down to [deuterium](https://en.wikipedia.org/wiki/Deuterium) and oxygen. It then takes the deuterium and with some hand waving fuses it together to make helium. This in turn releases massive amounts of energy that can power the super hero.
From the outside all you notice is that the hero drinks extra water and releases a bit of helium as a waste product.
[Answer]
I think the main problem is the energy storage. Your heroes can eat 20kCal by eating food (10 big macs with extra fries) all day long and drinking (+10 glasses of vodka and enough nuts to go with it) all night long, which will fit nicely to any story. Also they might recover their energy not in a single day but could take multiple days.
Now energy problem: you need superhuman metabolism to become superhuman. Do not think this as a higher functioning human metabolism. This one is different. Instead of ATP, sugars and fat, superheroes store their energy in a much more energy dense molecule which requires same amount of oxygen as sugars to burn but generates much more energy. Thus they do not store energy in sugar or fat but this ready-to-burn, extremely high calorie molecule which is also stored in blood for quick access.
[Answer]
The answer is simple ..
# dark matter
Says it all.
Note that the acts performed by "super-beings" are ridiculously outside of conventional physics.
Remember "the Six million dollar man" .. ? Sure, his arm was, let's say, some hyper material with incredibly strong motors. But when me picked up a car ... it would have *just crushed the other parts of his body*. In a similar way Superman simply could not do the things he does, even if his body per se, is astoundingly strong / powerful in a conventional sense.
Super-beings *go around* conventional matter-energy physics. It's obvious this involves dark matter / dark energy (which after all, *bends galaxies* .. !!!!! .. in a totally non-Newtonian manner which is completely mysterious to us).
Your super beings need conventional food only for their conventional metabolism and physics Newtonian spreadsheet.
The rest .. it's dark matter / dark energy. The same force system - which we currently do not know or understand - which *bends galaxies* against the conventional gravity of a whole galaxy - holy crap!
[Answer]
A simple way to make up the calories is if your characters drink two liters of canola oil per day. A liter of canola oil has over 8,000 calories. Combine that with more efficient digestion and usage of calories, and maybe they could cut that down to just a liter a day.
[Answer]
I often go with the "Superman" supplement route as described, but essentially diversify my range of energy sources. A lot of my superhumans exhibit some sort of... vampirism... that fuels their abilities. For example, my character with a Superman set of powers has them only while he holds an electrical charge. If he's low on power, he either has to conserve his ability use OR hope that one big burst of power can save the day OR find a sorce electrical energy fast. Either way, without holding any charge, he's as human as the innocent bystandards (I first came up with the character when Twilight was big... I billed the concept as a "Sparking Vampire" to play on the complaint of the "Sparkling Vampires".)
Other characters powers will eat at them unless they can find a source of fuel. For example a villain with telepathic and telekinetic powers would burn up his body if he doesn't feed off of other psychic energies to survive... which is fatal to his victims... thus, he can't consume the energy needed to do what he does by eating enough calories and needs to feed.
Other times, the lack of proper fuel is unrecoverable and part of the character's journey... it will be fatal and what they do with their abilities for their shortened life will be important. While this isn't the exact reason for it, I often attribute this to the reason why Bizzaro is Superman's clone (that is, the person who clones Superman did so believing that Superman was human and not an alien, so the result degrades because of the differences in physology between the two and the clone being unable to synthesize the protiens required for superman to do what he does). This was also discussed in the original Jurrassic Park film when they talked about the Lysine Contingency where the dinosaurs were genetically engineered to not produce the amino acid lysine and needed to consume it to prevent "slipping into a coma and dying" as Samuel L. Jackson explains it in what has to be his least badass attempt to kill something. Suffice to say, it was supplemented in the dinosaur's diet by humans (and if something went wrong, they would die out in a few days of denial of the supplement). Although this is highly unrealisitic, it's the general idea in that the extra energy requirements are features not bugs, when the superhuman is manufactured by someone seeking to control him/her (The reason the Jurassic Park example is bad science is because NO VERTIBRATE can produce lysine and have to have it supplied through diets. The sequel points addresses this when they point out the herbivores eat plants which do create lysine and the carnivors eat the herbavors, and get it that way... which in universe does work as the first film did point out that Hammond's attempts at control over animals no one has seen alive is woefully inadequate to the point of negligence.
] |
[Question]
[
I need a city-sized (10 km2 minimum) area to be declared inaccessible for 50 years minimum.
My thought was to justify this with a dirty bomb attack of some sort. [Radiological dispersal devices (RDD)](https://en.wikipedia.org/wiki/Dirty_bomb), while very realistic, have never been used or built (as far as I'm aware).
The only examples of lasting large scale area denial I can think of are things like Chernobyl; these involve very large amount of radioactive materials which are probably not believable for a smallish device. Are there materials which can accomplish this in relatively small amounts (say 100 kg)?
NOTE: The only point relevant is area denial. The "bomb" doesn't have to be destructive or deadly, a dispersal of radioactive material that persists in the environment is more than enough.
[Answer]
[](https://i.stack.imgur.com/ZG5Ni.jpg)
The true answer to your question can be found on a place called Anthrax Island in Scotland.
In 1942, British Military scientists experimented with various strains of anthrax to use as biological weapons during World War II. They bombed the small island with a particularly virulent strain of anthrax called Vollum 14578.
One of the reasons why anthrax didn't become a weapon is that the spores were really durable and if they used it as a weapon it would contaminate an area and render it uninhabitable for decades. It's hard to recover and rebuild when your livestock and farmers get wiped out by a pesky bacteria.
Gruinard Island remained contaminated for over 40 years because the cost of cleaning a .75 square mile island was cost prohibitive and very dangerous. Cleanup took four years and 280 tonnes of formaldehyde solution diluted in sea water to decontaminate less than one square mile of land. A flock of sheep remain on the island to act as a *"canary in a coal mine"*, to alert scientists they missed a spot.
Anthrax will fit your needs for your story. The best part is it's completely natural and organic. There's no pitchblende (uraninite) to collect and refine like you need for dirty bombs, just a good old fashioned deadly bacteria.
Good luck
* <https://en.wikipedia.org/wiki/Gruinard_Island>
* <https://en.wikipedia.org/wiki/Uraninite>
* <https://en.wikipedia.org/wiki/Anthrax>
[Answer]
# Somewhat realistic. Use a Cobalt Bomb.
For a realistic dirty bomb that has a has a 50 year minimum, city-sized lethality, where "realistic" is assumed to be a combination of cost-effectiveness and technological/military feasibility rather than political tenability, you'd want a [Cobalt Bomb](https://en.wikipedia.org/wiki/Cobalt_bomb).
As defined by Wikipedia: a cobalt bomb is
>
> a type of "salted bomb": a nuclear weapon designed to produce enhanced amounts of radioactive fallout, intended to contaminate a large area with radioactive material.
>
>
>
Basically a nuke wrapped with a layer of cobalt. Simple but extremely effective at area-denial because:
>
> Areas irradiated by fallout from even a large-yield thermonuclear weapon begin to increasingly become habitable again after one to six months; a cobalt bomb's fallout on the other hand would render affected areas effectively stuck in this interim state for decades of habitable, but not safely so under constant habitation, conditions.
>
>
>
By not safe, this means:
>
> After 10 half-lives (about 53 years), the dose rate would have decayed to around 10 mSv/hour. At this point, a healthy person could spend 1 to 4 days exposed to the fallout with no immediate effects.
>
>
>
At its worst, it has been theorized that one device
>
> containing 510 tons of Co-60 can spread 1 g of the material to each square km of the Earth's surface (510,000,000 km2). Radiation output from 1 g of Co-60 over one half life is equivalent to 44,000 GBq, which is sufficient to kill any inhabitants. If one assumes that all of the material is converted to Co-60 at 100 percent efficiency and if it is spread evenly across the Earth's surface, it is possible for a single bomb to **kill every person on Earth**.
>
>
>
In practice, the efficiency is much lower but (using back-of-the-napkin math) we can estimate that dispersal of 100kg of cobalt at an abysmal 1% conversion will have a lethal effect over 1000km2, 100 times the minimum. Considering that New York City is only 789km2, this amount is sufficient to convert most metropolitan cities into necropolises for the next few decades.
[Prior to being relieved of his duties](https://en.wikipedia.org/wiki/President_Truman%27s_relief_of_General_Douglas_MacArthur), Douglas MacArthur promoted the idea of using Cobalt across the Korean Peninsula. As he recounted in his memoirs:
>
> Of all the campaigns of my life, 20 major ones to be exact, [Korea was] the one I felt most sure of was the one I was deprived of waging. I could have won the war in Korea in a maximum of 10 days.... I would have dropped between 30 and 50 atomic bombs on his air bases and other depots strung across the neck of Manchuria.... *It was my plan as our amphibious forces moved south to spread behind us—from the Sea of Japan to the Yellow Sea—a belt of radioactive cobalt.* It could have been spread from wagons, carts, trucks and planes.... For at least 60 years there could have been no land invasion of Korea from the north. **The enemy could not have marched across that radiated belt**."
>
>
>
Note that, he's arguing not for *detonating* but *dispersing*, which is directly in line with area-denial and not necessarily with immediate mass-murder.
As for actual implementation: the U.S. investigated the idea in the 60's but chose not to move forward, for reasons not formally stated. The British gave it a go and after some setbacks, withdrew (thus the "somewhat" qualifier). Russia, on the other hand, does not have the same qualms and [is rumored to have a few warheads stockpiled](http://www.bbc.co.uk/news/world-europe-34797252).
For further reading, I recommend:
<https://en.wikipedia.org/wiki/Salting_the_earth>
And:
<http://tvtropes.org/pmwiki/pmwiki.php/Main/SaltTheEarth>
Specifically, the "Real Life" section.
[Answer]
>
> It's worth noting that Chernobyl is a great example of how difficult this problem is. 30 years after the explosion you have people that live there. Tourism is growing. Etc. Due to uneven distribution of radioactive matter there are hot spots, but vast areas that are almost clean. Just over half the OP's time requirement and the worst nuclear disaster in human history already fails his needs.
>
>
>
**Deployment**
Doing this with a single explosion is unrealistic. Nagasaki and Hiroshima were re-occupied almost immediately. Chernobyl required the destruction of an entire reactor (if all you consider is just the reactor assembly itself and none of the shielding, it's still massive compared to a missle). Besides, the one-explosion solution means very dense "denial" material at the center and almost nothing at the edge of the radius.
I'd suggest a MIRV. One missle, many warheads, more even distribution.
**Material**
Looking at a [list of radioactive isotopes](https://en.wikipedia.org/wiki/List_of_radioactive_isotopes_by_half-life#109_seconds_.28gigaseconds.29) I'd vote for either Caesium-137 (30 year half-life) or Titanium-44 (63 year half-life).
**The Real Problem: Cleanup**
Ash is completely correct that cleanup ruins your plans. If you remove the source, the remaining radioactivity decreases by the "[Rule of 7](https://worldbuilding.stackexchange.com/questions/91777/how-long-would-it-take-for-the-planet-to-recover-from-an-apocalyptic-event/91817#91817)" (by 90% every 7 hours). In most instances, this means your property is re-inhabitable in a dozen years because there's no actual radioactive source.
Therefore, the question is, "how do I get my radioactive source so embedded into the environment that it's not practical to clean it up?"
There's no easy way to do this. Things like RDD's will cover the surface, but the surface can be processed. Thanks to painfully nasty things we've done in the U.S. over the decades (like mining without caring a whit about the environment), our EPA has [superfund cleanup procedures](https://www.epa.gov/superfund/superfund-cleanup-process) that go so far as to remove the top 18"-24" of dirt, haul it away to a prepared containment area, and replace it with clean dirt. In other words, the cleanup process already exists.
Off the top of my head, I don't know how you'll get around this. If the area was difficult to access or located in a 3rd-world country, then cleanup may simply never happen. But if it's in a 1st-world country, you'll have trouble keeping the area inaccessible for longer than maybe a decade. The size of the area is actually pretty small compared to superfund cleanup areas I'm familiar with, so its size will not be a deterrent. Or you'd need to figure out how to get the radioactive material deep into the ground: 3-4 feet at least. But explosions (especially [RDD](https://www.nrc.gov/reading-rm/doc-collections/fact-sheets/fs-dirty-bombs.html) explosions) don't really bury things. It's a tough nut to crack.
[Answer]
If the area is not an actual city but land, and was occupied, [land mines](https://en.wikipedia.org/wiki/Land_mine) are pretty effective as deterrent. While they won't make area completely unapproachable, even with extensive and expensive demining the area will be uninhabitable for general population for decades (and even after decades and extensive cleaning, people will sometimes get themselves killed or maimed by unfound ones).
Even if they are not in huge number, fear of not knowing where there (and news reports about people hitting them) will keep most people out.
And, opposed to most other answers, dangerous area is fixed and danger will not spread out to other locations.
(Unfortunately, lesson from my country history)
[Answer]
Biological and nerve agents will either decay or risk being transported elsewhere; for biological agents there's the added risk of spreading whatever pathogen is used.
I feel that this only leaves radiological agents and [killerbots](https://en.wikipedia.org/wiki/Second_Variety).
The first have the problem of dispersal; how do you contaminate the area in such a way that it is not worthwhile to have it cleaned (a *city* is valuable property!)? You'd need a mix of volatile dispersal (i.e. yeah, a dirty bomb) and some way of ingraining the radioactivity in the soil to such an extent that remediation simply isn't possible.
Normal soluble radioactive compounds will not penetrate very deep even when washed by either alkali or acid rain, and anyway, a city is probably mostly coated in stone, bricks and asphalt.
You would need a much more destructive approach - orbital bombardment with salted staballoy penetrators. They would be designed with a coating to ensure they'd start burning very low in the atmosphere, disseminating a part of their radioactive load like a dirty bomb, then embed deeply into the ground. There, they would contaminate the water table and ensure that unstable isotopes surface slowly in the following decades. Removing the penetrators would mean completing the destruction of the area, and simply covering the entry holes would not be an acceptable solution for long-term habitation.
Radiation background would be quite high at the start, from the deposited aerosols, then would go down (faster if the area is decontaminated e.g. with pressure jets), then up again - for example as the 228Ra or 228Th used to salt the penetrators decay into radon gas, that slowly seeps upwards - and finally slowly decay again.
Killerbots require even more advanced technology, and the time period could be that of their nuclear battery decaying until it can no longer power the bot weapons. Before that, anyone entering the no-go area would risk a laser strike to the head from a bot hidden in the shadows.
**Not** really all that feasible, as killer-killer-bots could be easily employed to overpower the defendants (like Roger Zelazny's *Qwibbian-Qwibbian-Kel*), and locating a slightly radioactive killerbot is probably not so impossible; and they might be vulnerable to EMPs, [virtual-cathode oscillator bombs](https://www.globalsecurity.org/military/library/report/1996/apjemp.htm), near-field resonators or simply having to hide in the sewers for years.
[Answer]
# A dirty bomb will not do it alone
**Summary: you can do it, if you...**
* **take care to make the fallout set deep in buildings and soil**
* **hit an area of little economic interest (i.e. budding ghost town)**
* **create fear and myth about the area**
Using a dirty bomb (RDD) can easily raise the level of background radiation in an area of that size, to such an amount that if is not economically viable any more. When you say:
>
> Chernobyl [involved] very large amount of radioactive materials
>
>
>
...you are actually wrong. For example: the entire inventory of Iodine 131 in reactor 4 as it blew, is measured in 1-2 kg. Yeah, it accounted for a scary amount of radioactivity — measured in billions of billions of Becquerel — but its **mass** when compared to mundane objects is tiny.
It should perhaps be noted that 10 km2 is quite a small town... comparable to a square that is 3.3 km / 2 mi on the side. By comparison the [Chernobyl Exclusion Zone](https://en.wikipedia.org/wiki/Chernobyl_Exclusion_Zone) is 2,600 km2
So if you steal a few [medical sources](http://www.world-nuclear.org/information-library/non-power-nuclear-applications/radioisotopes-research/radioisotopes-in-medicine.aspx), and grind these to fine aerosols, you can easily contaminate 10 km2, no problem. If you make the contamination spotty and uneven, you can cover the same area with even less.
# The problem...
...is that fallout is **dust**. Fallout is tiny particles that are radioactive. Once you remove the particles, simply by cleaning the dust out, you have removed the radiation with them. This is what **decontamination** is all about: mechanically picking up the dust and moving it away. It is physically easy to do.
So to reclaim an area that has been decontaminated is not all that hard. But you can make it harder, and not as interesting to do it.
# Solutions
You need two things...
1. make it hard (read: **expensive**) to remove the fallout
2. make people not want to return
The more superficial the dust is, the easier it is to remove. You need this dust to go deep into the buildings, and into the soil. If you can make fallout turn up more than a meter down the soil, then it becomes extremely expensive to remove it.
Also, the less **incentive** there is to clean things up, the less likely it is that people will bother. There are plenty of "hotspots" today where there is enough radiation that you cannot actually live there, if regulations were to be followed, like some places around [Ytterby Mine](https://en.wikipedia.org/wiki/Ytterby). But no-one bothers to decontaminate that place because it is not of any economic interest.
So if you hit [a place where people are already moving out and abandoning it](http://all-that-is-interesting.com/abandoned-detroit-photos)...
[](https://i.stack.imgur.com/ux0nA.jpg)
*[Packard Automotive Plant](https://en.wikipedia.org/wiki/Packard_Automotive_Plant), Detroit, USA, present day*
...you are greatly extending the time it will take before people will bother with cleaning the place up.
And if you employ the help of our good friends in the anti-nuclear power movement, experts at radiation scare-mongering and such propaganda... then you are set.
[Answer]
**A Dirty Bomb would do it**.
By exploding radioactive matter such that it disperses over that area like a dust would certainly achieve your affect. This doesn't require that much matter. If you crush your radioactive matter into a fine enough dust and detonate it high enough the particles can easily cover enough of an area.
**A Fungal Biological agent would work too**
Create a fungal agent that can be dispersed over an area and have a lifespan of 50 years. Similar to anthrax.
I do slightly protest your notion of "deadly" whatever you use must be scary enough to deter people from intentional exposure. Radiation and anthrax are area deniers because they CAN kill you, though death isn't necessarily certain.
[Answer]
It is going to take a *lot* of radiation and a lot of contamination to make any area irredeemable given modern clean-up techniques, so you'd want one of; A. something that throws out neutron radiation and creates secondary radioisotopes in the surrounding material and/or B. is extremely toxic in it's own right *as well as* being radioactive.
Coverage may be an issue, you *are* talking about a weapon that spreads significant quantities of heavy metal for a little over a kilometer in every direction. If that's not an airburst weapon but a bomb planted on the ground the primary explosive will have to be pretty big to create that kind of dispersion.
As to size 100kg of something like Plutonium or Polonium, both fit A and B above, would definitely be more than enough, if spread as a fine powder, to poison that much ground. This is in no way a small amount of radioactive material though, a couple of hundred *grams* of that stuff is a LOT.
Personally given the issues involved in spreading material explosively I would go with either A. a crop-duster or B. poisoning the city water supply directly. These methods are more reliable and just as likely to cause the area to be inaccessible for an extended period of time.
There are some issues around timing here, the best isotopes for area denial are also have some of the longest half-lives ever observed, however you could use something like Strontium-90, 20 odd year half-life, nasty health effects (it goes to the bone and replaces Calcium for a start), plus the radiation and it yields other toxic and radioactive daughter isotopes. Strontium won't however yield the same sort of neutron contamination so it's only a threat for as long as it can't be cleaned out of the area.
[Answer]
Area denial is mostly about risk. It is very unlikely that you can make an area totally unsurvivable for 50 years without extensively contaminating many areas around it through rain water runoff, dust, and ground water contamination. Even Chernobyl is able to be visited today, but there is *long term risk* to living there, so it remains a mostly abandoned area. Troops wearing protective gear could go through almost any contaminated area immediately, though PPE (personal protective equipment) makes living very difficult and wears out soldiers very quickly.
Chemical agents do not normally persist on the surface for decades (they are covered, broken down by sunlight, or stripped away by wind/rain) but may linger in interior spaces or in ground water. Biological agents are even shorter lived without a living vector to carry them, other than specialized fungal spores. Radiological agents like your dirty bomb have sufficient half-life and more importantly, generate **fear** which will deter folks from going through an area. Even with documented "safe" levels of radioactivity, an area affected by a radiological agent is going to be avoided, at least within living memory (as opposed to areas that experience regular floods, wild fires, or earthquakes, something about radiation generates a primal fear response).
Consider the many cancer deaths of the crew and cast from the John Wayne film "The Conquorer", which was filmed in an area with a lot of nuclear testing fallout. Even this fairly "dirty" area could still be lived in for weeks and the potential negative effects don't show up for years. So while it may be difficult to deposit enough radiologic material to acutely affect humans, if it is hot enough to be detectable then no one will live go there for fear of getting ill. Even more so if someone puts up "DANGER, RADIATION" signs all over since there may be little visible evidence of contamination.
You do have other options. An area can be mined (the US uses timed minefields for short term area denial, but other countries or older conflicts certainly did not), seeded with slow growing plant life that have toxic spores, active defensive machines that can exist in a dormant state until roused by human activity (depending on your technology level), or rendered geologically uninhabitable (for example, there are periodic releases of subterranean gas pockets that suffocate surface organisms, like CO2 gas).
] |
[Question]
[
What would happen if the entire inner surface of a Dyson sphere (not necessarily a solid shell, maybe a very dense swarm) would be coated into a highly reflective material?
Let's say it can reflect 99.9% at all wavelengths.
Would it cook the star in its own light?
[Answer]
Building on [L.Dutch's answer](https://worldbuilding.stackexchange.com/a/82863/394):
* Even if mirrors are very efficient and reflect 99.9% there still remains that residual .1% of energy they absorb.
* (almost) All energy is prevented from escaping and thus accumulates inside the sphere.
* Temperature inside the sphere will rise (quasi) linearly.
* Ditto for both radiation and solar wind.
* It is not said if the solar wind is allowed to pass, is absorbed by mirrors or is reflected (how?) back.
* In any case temperature of mirrors will rise and they will start to radiate ([Black Body](https://en.wikipedia.org/wiki/Black-body_radiation)) emitting energy proportional to the fourth power of Temperature (K) (Stefan-Boltzmann law).
* If mirrors are sturdy enough to withstand temperature and pressure (solar wind) they will come to an equilibrium with power radiated by mirrors equaling the power produced by the star.
* Temperature of equilibrium will be lower for larger spheres and thus the "color" of the sphere will change (Wien's law).
* In general the amount of radiation within the sphere, at equilibrium, will be about 1000 times the "normal" radiation (under your assumption a photon has to bounce, on average, 1000 times before getting its fair chance to be absorbed).
* In extreme cases (small, **very** sturdy sphere) increment in temperature in the star may be enough to ignite higher level nuclear reactions without need of the normal Exhaust Fuel -> Gravity Contract -> Heat Up -> Ignite "next" Fuel cycle. In that case a Very Anomalous Supernova may result (I doubt your mirrors will withstand *that*)
[Answer]
Light emitted from the star would travel until the mirrors and then would be reflected back, bouncing back and forth. Due to enormous scale of the Dyson sphere, you can neglect cavity effects and related wavelenght selection.
This would build up energy into the sphere, which can only dissipate through the mirrors.
Basically such a configuration would act as a cosmic scale black body (mind I say black body, not black hole).
If your mirrors can withstand the energy contained inside the sphere, the ensemble will behave like a new star with the size of the Dyson sphere, emitting like a black body at the temperature of the mirror.
If your mirrors are not so sturdy they will simply evaporate and join the stellar wind.
[Answer]
And now, to do away with pointless talk and actually do some science.
Theoretical body which absorbs all the light is called black body, theoretical body which doesn't absorb all the light but absorption efficiency doesn't depend on wavelength is called grey body. Object for which absorption depends on wavelength is called coloured body.
Curious property of grey bodies is that they not only absorb light less effectively than black bodies, they also emit light less effectively, assuming same temperature.
Energy emission per unit of surface for grey body is:
$$
j = \epsilon \* \sigma \* T^4[\frac{W}{m^2}]
$$
where $\epsilon$ is absorptivity/emissivity, $\sigma$ is Stefan-Boltzmann constant and $T$ is temperature in Kelvins. Square brackets contain dimensions.
Your theoretical sphere will emit:
$$
P = 2\*4\pi R^2\epsilon\sigma T^4 [W]
$$
Where $R$ is radius of sphere. Notice factor of 2 at the start. That's because it will emit to the outside and to the inside (I deliberately wrote it as $2\*4$ instead of just $8$).
Meanwhile, star emits:
$$
P\_s = 4\pi r^2\sigma t^4 [W]
$$
Considering that entire shell is reflective, we can assume that reflected star light does not fall on other parts of the shell and instead returns to star to be fully absorbed (stars are with good approximation black bodies). However, internal emission of the shell with be into half-full spatial angle, thus we can't make such assumption.
Star will absorb back all the emitted light which falls on it, but shell will again absorb only $\epsilon$. Since from each infinitesimal part of the shell star obscures only part of the full angle we can see that star will absorb $\frac{\pi r^2}{2\pi R^2}=\frac{r^2}{2R^2}$ of total internal emission. This means that $\epsilon(1-\frac{r^2}{2R^2})$ will be absorbed by shell while $(1-\epsilon)(1-\frac{r^2}{2R^2})$ bounce again, thus star will again absorb $\frac{r^2}{2R^2}(1-\epsilon)(1-\frac{r^2}{2R^2})$. This looks like a geometric sequence with first term of $a=\epsilon(1-\frac{r^2}{2R^2})$ and multiplicative factor of $q=(1-\epsilon)(1-\frac{r^2}{2R^2})$. Since obviously $q<1$ sum of the sequence converges. Summing from 0 to infinity we get:
$$
A\_{shell}=\frac{\epsilon(1-\frac{r^2}{2R^2})}{1-(1-\epsilon)(1-\frac{r^2}{2R^2})}
$$
Now we need to calculate same series for absorption by star and we will be able to calculate total fraction of internal emission absorbed by star to internal emission absorbed back by shell. This time we get $a=\frac{r^2}{2R^2}$ and $q=(1-\epsilon)(1-\frac{r^2}{2R^2})$, thus sum is:
$$
A\_{Star}=\frac{\frac{r^2}{2R^2}}{1-(1-\epsilon)(1-\frac{r^2}{2R^2})}
$$
Since obviously all the internal emission has to be absorbed over course of infinite bounces, $A\_{Shell}+A\_{Star}=1$ has to be true. And indeed it is, verifying that no mistakes were made.
Thus, over infinite reflections of internal emission, shell will absorb back:
$$
A\_{Shell}\*P=\frac{\epsilon(1-\frac{r^2}{2R^2})}{1-(1-\epsilon)(1-\frac{r^2}{2R^2})} 4\pi R^2\epsilon\sigma T^4
$$
While star will absorb:
$$
A\_{Star}\*P=\frac{\frac{r^2}{2R^2}}{1-(1-\epsilon)(1-\frac{r^2}{2R^2})} 4\pi R^2\epsilon\sigma T^4
$$
Thus total power absorbed by shell will be:
$$
A\_{Shell}P+\epsilon P\_s=\frac{\epsilon(1-\frac{r^2}{2R^2})}{1-(1-\epsilon)(1-\frac{r^2}{2R^2})} 4\pi R^2\epsilon\sigma T^4 + \epsilon 4\pi r^2\sigma t^4
$$
Which for equilibrium has to be equal to total emitted power:
$$
P = 2\*4\pi R^2\epsilon\sigma T^4
$$
Combining those equations we get T as a function of t,r,R and $\epsilon$:
$$
T=t\sqrt{\frac{r}{R}}\sqrt[4]{\frac{1}{2-\frac{\epsilon(1-\frac{r^2}{2R^2})}{1-(1-\epsilon)(1-\frac{r^2}{2R^2})}}}=t\sqrt{\frac{r}{R}}\sqrt[4]{\frac{\epsilon (1-\frac{r^2}{2R^2})+\frac{r^2}{2R^2}}{\epsilon (1-\frac{r^2}{2R^2})+2\frac{r^2}{2R^2}}}
$$
Unfortunately, for star it's more complicated.
Simplified equilibrium requires that temperature raises enough so that total emission is equal to original star emission plus reflected starlight plus absorbed internal shell emission.
In practice, it will increase temperature, increasing rate of fusion, which increases internal power generation, increasing temperature even further. I can not at this point make predictions on this. So I will continue with grossly oversimplified equilibrium conditions. Thus, in grossly oversimplified conditions, star temperature has to raise so that following are true:
$$
P'\_s=P\_s+P\_s(1-\epsilon)+P\_s(1-\epsilon)^2+...+A\_{star}P=\frac{P\_s}{\epsilon}+A\_{star}P
$$
Term $\frac{P\_s}{\epsilon}$ represents infinite series of starlight bouncing from shell, being absorbed by star, emitted again, bounced, absorbed and so on.
Which after using expressions, using expression for T(t) and simplifying a bit:
$$
t'^4=\frac{t^4}{\epsilon}+\frac{\frac{r^2}{2R^2}}{1-(1-\epsilon)(1-\frac{r^2}{2R^2})}\epsilon \frac{\epsilon (1-\frac{r^2}{2R^2})+\frac{r^2}{2R^2}}{\epsilon (1-\frac{r^2}{2R^2})+2\frac{r^2}{2R^2}} t^4 =\frac{t^4}{\epsilon}+ \frac{\frac{r^2}{2R^2}}{\epsilon (1-\frac{r^2}{2R^2})+2\frac{r^2}{2R^2}}\epsilon t^4=t^4(\frac{1}{\epsilon}+\frac{\frac{r^2}{2R^2}}{\epsilon (1-\frac{r^2}{2R^2})+2\frac{r^2}{2R^2}})
$$
Which means that simplified equilibrium temperature of star will be:
$$
t'=t\sqrt[4]{\frac{1}{\epsilon}+\frac{\frac{r^2}{2R^2}}{\epsilon (1-\frac{r^2}{2R^2})+2\frac{r^2}{2R^2}}}
$$
And final temperature of shell will be T'=T(t'):
$$
T'=t'\sqrt{\frac{r}{R}}\sqrt[4]{\frac{\epsilon (1-\frac{r^2}{2R^2})+\frac{r^2}{2R^2}}{\epsilon (1-\frac{r^2}{2R^2})+2\frac{r^2}{2R^2}}}=t\sqrt[4]{\frac{1}{\epsilon}+\frac{\frac{r^2}{2R^2}}{\epsilon (1-\frac{r^2}{2R^2})+2\frac{r^2}{2R^2}}} \sqrt{\frac{r}{R}}\sqrt[4]{\frac{\epsilon (1-\frac{r^2}{2R^2})+\frac{r^2}{2R^2}}{\epsilon (1-\frac{r^2}{2R^2})+2\frac{r^2}{2R^2}}}
$$
Now it's just a trivial matter of calculating unimportant details. Feel free to put in whatever values you want.
Obviously, you can calculate external emission of the shell to know how much power will that pseudo-star output. Simply use $P=4\pi\sigma\epsilon T'^4$.
EDIT:
Disclaimer: expression $\frac{r^2}{2R^2}$ comes from assumption that shell is significantly larger than star. If you want shell to be merely slightly larger, replace it with $\frac{r^2}{R^2}$
[Answer]
It is also conceivable that the mirrors are not absorbing the remaining 0.1% of the radiation, but are letting it through. In that case, the intensity of the radiation outside the sphere won't change, while the intensity inside the sphere will increase 1000-fold (assuming the mirrors are able to withstand it).
[Answer]
Hopefully not. I do not like to think about what would happen to my tyrannical plans should the sun be overcooked. I mean, the Dyson sphere would reflect the 99.9% energy to the solar energy batteries set up in space to collect the energy, not back at the sun correct? Isn't that the concept of the Dyson sphere?
We wouldn't be reflecting the energy back towards the sun at any rate. And in all probability we would not be able to reflect 99.9% of all the energy coming towards our solar mirrors. There would most likely be at least a little bit of energy escaping or refracting off because of space debris damaging our mirrors AND collectors. Now with that model the internal temperature of the sun would not be as high as our highly intelligent friend calculated for us. We MUST think of our Dyson Sphere in a constant state of disrepair, because that would be the most likely outcome.
] |
[Question]
[
If I were to build a world like Game of Thrones, how would the dragons not burn their own nostrils from the heat of flames?
[Answer]
Same way a lighter works. See [wikipedia.](https://en.wikipedia.org/wiki/Lighter) But to summarise, you might want to ask yourself why a lighter doesn't melt. It appears as though the flame is coming from the lighter, and yet the inside of the lighter is not burned. You can look at the mechanics and principles behind the way a lighter works and apply it to a biological creature.
So the creature may have a flammable gas that it breathes out from a special organ, and it uses another method to ignite it, on the way out.
You should be studying every kind of gas-flame fuel and how they work on a mechanical level.
EDIT: Some of this is also going to depend on what type of fire breath we're talking about--some fictional dragons give us fire from their noses, or their mouth, or both. Establish which of these you are doing and you can start to set up the mechanics for that.
[Answer]
jamesqf has basically given the answer in his comment to the OP.
The dragon exhales flammable gas at high pressure, that either ignites on contact with air or is lit by a spark as it leaves the dragon's maw. Or possibly even a low flashpoint gas that gets heated by the pressure of exhalation and catches fire as soon as it finds some oxygen.
Either way, as long as it's blowing at sufficiently high pressure, the heat is conducted away from the dragon, rather than towards it.
It's the same principle as they use in fire breathing in circuses. See: <https://youtu.be/h3czvJNTqUQ>
The risk to the dragon, as to fire breathers, is when they're stopping. The decrease in pressure will cause the flame to travel back and scorch the dragon's face for a fraction of a second.
In order for the above to work, the dragon needs to have a separate sac for storing fuel, that is separate from it's lungs, and a mechanism to ensure that both the fuel sac and lung pathways are not open at the same time. But even humans already have that---it's called belching.
[Answer]
In our world, dragons are smaller and have six legs - the [bombardier beetle](https://www.wired.com/2014/05/absurd-creature-of-the-week-bombardier-beetle/) protects itself from heat partially by the reaction being in a thick skinned chamber, and mostly by ejecting the hot gas away from itself.
[Answer]
I think the term you and many others are really looking for here is **hypergolic**.
## [Hypergolic Fluids](https://en.wikipedia.org/wiki/Hypergolic_propellant)
A *hypergolic* combination essentially means the two will combust on contact with one another.
They are mainly used in rocketry where it's necessary to have reliable ignition (and re-ignition) when you're pumping massive amounts of fuel and oxidizer into the engine nozzle, and because of the extreme temps & pressure (or vacuum) a regular spark plug won't cut it.
### Common Hypergolic Propellants:
* [Unsymmetrical dimethylhydrazine](https://en.wikipedia.org/wiki/Unsymmetrical_dimethylhydrazine) (UDMH) + [nitrogen tetroxide](https://en.wikipedia.org/wiki/Dinitrogen_tetroxide) (N$\_2$O$\_4$)
* [Aerozine 50](https://en.wikipedia.org/wiki/Aerozine_50) + nitrogen tetroxide (N$\_2$O$\_4$) – Aerozine 50 is a mixture of 50% UDMH and 50% straight [hydrazine](https://en.wikipedia.org/wiki/Hydrazine) (N$\_2$H$\_4$)
* [UH 25](https://en.wikipedia.org/wiki/UH_25) is a mixture of 25% hydrazine hydrate and 75% UDMH.
Hydrazine is easily my favorite, so I tried to incorporate the ones that use it, which is most of them. It's also used as a [monopropellant](https://en.wikipedia.org/wiki/Monopropellant) for the Reaction Control Thrusters ([RCS](https://en.wikipedia.org/wiki/Reaction_control_system)) in most spacecraft to control attitude (direction), because hydrazine is so reactive it will also combust all on its own just by coming in contact with an [Iridium](https://en.wikipedia.org/wiki/Iridium) catalyst. (tho not as high energy as other reactions)
Fun fact about ***The Martian***:
>
> This fuel (and possibly same catalyst also?) is the same that Mark Watney stole from their **MDV** (Mars Descent Vehicle) to make extra water. He disassembled the rocket engine to get to the catalyst, broke it apart so as not to cause a full reaction, and dripped Hydrazine (**N$\_2$H$\_4$**) over it to [break it down](https://en.wikipedia.org/wiki/Hydrazine#Rocket_fuel) into ammonia, nitrogen, and hydrogen (**8 H$\_2$**), which he funneled up a makeshift chimney to a flame to burn off the hydrogen gas (**H$\_2$**) so it would react with the oxygen (**O$\_2$**) in the atmosphere and combine to form water (**H$\_2$O**), which his water reclaimer would pull out of the atmosphere and store in tanks. His oxygenator scrubbed his breath (**CO$\_2$**) for oxygen (**O$\_2$**) and stored it in tanks, so he needed hydrogen to make water.
>
>
>
### Advantages:
Most hypergolics are very stable for long durations and stay liquid at room temperature.
### Disadvantages:
Most are also famously **toxic** and **corrosive**. The people who handle them have to wear [full body pressurized suits](https://www.youtube.com/watch?v=QN8kjvlePBw) with oxygen tubes (essentially spacesuits). You can only imagine with a chemical this reactive, what would happen if you inhaled it, or touched it.
Plus, it helps that most of them are also clear and colorless like water, odorless, and tasteless. Awesome.
# Dragons:
In movies with dragons or dragon-alike creatures (Godzilla), I've repeatedly seen when they show the up-close details of **fire breathing**, they show two liquids being squirted out of separate glands in the mouth, and there's no fire until the two make contact.
This is a **hypergolic** reaction and would not burn the dragon at all. The liquids do not need to be at a high temperature, and depending on angles of glands, the reaction could take place far away from the dragon's face.
The real issue here is the extreme **toxicity** and **non-organic** nature of these chemicals, and since these are fictional beasts I'm not sure how far you want to go before just calling it *magic*. There does exist some relatively non-toxic hypergolic propellants out there, and possibly ones we haven't discovered yet that are closer to **organic chemistry**, if you want to go that route.
### Chemistry is cool again! (You're welcome) ;D
I've never been a big fan the traditional sciences, math, chemistry, all seemed drab and boring. But rockets and going to **SPACE** are all pretty neat, and what do you know, rocket science is actually really hard and combines nearly every type of science mankind knows of.
Plus, I was super excited to find out that **this is actually a real reaction which people use daily**, and *hypergolic* is just a freakin' cool word that everybody wants to know and use. Cheers!
[Answer]
The dragon scales are heat insulating. A classic thing for the dragon scales in fantasy is to have all kind of special properties like being the strongest material etc.
[Answer]
There are a few possible answers to this questions that can fall along the range of fact and fiction. I will address the question with regard to several types of dragons.
1) Magic. For dragons that use magic to produce fire, the simplest answer is that the same magic that makes the fire also protects the dragons face from the heat of the flames. (See D&D Dragons).
2) Science! For the style of dragon that uses venom that combusts when exposed to air or mixing with another venom, the speed in which those fluid leave the dragons mouth cause the reaction to happen away from the dragons face. (See Reign of Fire)
3) Science again! For dragons that use a combustible gas. Once again the reaction would be happening a foot or two in front of the dragon's face because there would not be oxygen to burn within the dragon’s mouth. (See Bunsen burner/butane torches)
All of these dragons would likely be evolve for fire resistant scales, but I hope I have addressed how the sensitive parts of the face might be protected.
P.S. The GoT dragons fall into the first category.
[Answer]
May be they do burn their nostrils as baby dragons.
I think you can compare it to e.g. goldsmiths.
In the beginning a goldsmith has very sensitive hands, like everybody else. But due to constant work with hot metal, the fingers get a horn skin / cornea, which makes them able to touch 300-400°C hot metal rings.
This may happen in a way to dragons too. Due to spitting fire from time to time, the skin around the nostrils gets thicker and more... (i won't put the word horny here) adopted to the heat of the flames.
(Source: My wife is a goldsmith an I have seen her catching rings that were lying under a flaming torch seconds ago and then dropped)
BR
Alex
[Answer]
>
> **The trick, is not minding that it hurts** - Lawrence of Arabia
>
>
>
When you see dragons breathing fire, they are usually either angry or defending themselves, the sort of situations in which a human or any other creature might ignore a fairly significant amount of pain and lash out anyway.
For example, Smaug was livid at the thought of anyone trying to steal his gold and decided to torch Lake Town as revenge, but in the book it is stated that he had not done that sort of thing in a long time and had forgotten how good it felt. It's not canon that his snout really hurt afterwards and that was why he rarely did it, but the idea is somewhat consistent.
[Answer]
You know, the dragons technically dont have to be completely flame-resistant. Im doing a research project on dragonflame and I have something I call the "Bumblebee Effect." The dragon only has to be able to produce flame, but the flame has the liability to combust on its caster since the method of flame in my research is methane and hydrogen. Similar to how a dragons flame may hurt or kill it, the bumblebee cannot survive stinging an enemy. This also eliminates the arguement of "it`s faulty evolution"
[Answer]
The chemical that the dragon breaths don't combine and ignite until theyou leave the dragons mouth. Once outside the Dragons body then the dragons heat insulating scales.
[Answer]
In game of thrones Dragons are **simply immune to fire** (bolognum: no in world plausible explanation), and any person that has dragons' blood inside its body is immune to fire and heat too. Note that other characters are immune to fire/heat, but for different reasons.
So if you are asking how in Game of thrones we have living beings immune to fire, **there's no explaination** apart the usual "magic" argument.
**Your story your rules.**
If you are asking how can someone in nature be immune to fire/heat:
* **no single living being is immune to fire**.
* probably there's no life at all after 1000 C°.
* prolonged exposition to much heat will be damaging anyway anyone.
* carbon based living beings are made mostly by **water and carbon**
* **waters boils at 100 C°** and carbon have a plenty of various chemical reactions that happens at different temperatures.
* **cells are made basically of fat** which just fries below 300 C°
**So possible real-world explanations:**
* Actually the dragon is not touching the fire directly (combustion happens far away)
* Actually the dragon has some coolant that is going to be exausted (like water from additional glands)
* Actually the dragon is not a regular living being (no cells made of fat: it could be a robot)
* The skin and heat-related body parts are protected by **something**
**"Something" explained:**
What can protect from heat and be naturally produced? **Foam**! Foam is perfect for isolating from heat, and we have plenty creatures in our real world that produces foam for some reason or another (I doubt anyone tested those foams as heat insulator anyway).
Also foam can be quickly replaced to keep temperature down:
assume for a second the dragon has some kind of callus that protect from heat (it can be just dead tissue or some body-produced ceramic): if we managed to keep the callus exposed enough time to heat the callus may become very hot thus starting burning the below meat, and since materials resistant to heat can also store much heat, once the callus is hot it will fry the dragon for very long time. That's why callus is a bad idea while foam is slightly better.
[Answer]
How do electric eels not shock themselves? How do venomous snakes and spiders and so forth not poison themselves? There are lots of real world examples where creatures have evolved to have self-protection from the dangerous and deadly things they can do. Some we understand, others we don't. Put dragons into the same category.
It might be a nice theoretical discussion for your characters, but I don't think you need to provide an explanation for it. "We don't know" is a sufficient answer.
[Answer]
Make it so that the dragon spews two different liquids (carried in two different sacks each on the opposite side of the mouth) that ignite when they combine. The streams of the two liquids intersect in front of the dragon and ignite at a relatively safe distance. The dragon would also of course have scales/skin on it forward facing regions that could handle the heat.
[Answer]
In Game of Thrones, Targaryen lineage are fire immune by magical means.
It's obviously not a physical process which protected Daenerys in Drogo's funeral pyre. She'd definitely burn (pyrolize, boil) if not for magic.
Therefore we can say that dragons in GoT universe might be fire immune by same, magical, means.
] |
[Question]
[
I am considering whether a pre-Industrial civilisation could carry on for millennia on an Earth-like planet without entering the Industrial Age.
Of course, regularly destroying everything with plagues, earthquakes, etc and sending people back to the Bronze Age might do the trick, but I am looking for something more subtle.
For example, would a lack of readily-accessible iron ore prevent steam combustion engines from being practical? And is it believable on an Earth-like planet that iron ore would be that inaccessible?
[Answer]
**An early Industrial Revolution needs cheap energy**. Fossil fuels and coal were essential to it.
**Just make fossil energy hard to find, or too expensive to extract**, and all economic incentives to start changing all the technology and all the society will vanish. First steam engines were placed in coal mines to extract water from them and avoid flooding. They were made just because it was cheaper to use coal powered machines than using animal or human powered devices.
>
> Societies before the Industrial Revolution were dependent on the annual cycle of plant photosynthesis for both heat and mechanical energy. The quantity of energy available each year was therefore limited, and economic growth was necessarily constrained. In the Industrial Revolution, energy usage increased massively and output rose accordingly. The energy source continued to be plant photosynthesis, but accumulated over a geological age in the form of coal. This poses a problem for the future. Fossil fuels are a depleting stock, whereas in pre-industrial time the energy source, though limited, was renewed each year.
>
>
>
*[Energy and the English Industrial Revolution](http://rsta.royalsocietypublishing.org/content/371/1986/20110568)
E. A Wrigley
Philosophical Transactions of the Royal Society 2013.*
From these first uses, steam engines were developed into sea and land vehicles. Other kind of engines, like internal combustion ones, were developed only after fossil fuel powered vehicles became relevant.
If there were not any cheap coal or petrol, engineers still could develop engines powered by olive oil or alcohol, but they would not be economical enough to substitute horses, oxen or wind. Society would not change abruptly so there would not be any "revolution". Greeks and romans knew some sort of steam engines but their slave powered economy didn't need any development of these machines.
**Ways to make fossil fuels impractical:**
Centuries before the revolution you could seed coal and oil deposits with genetically engineered bacteria that would metabolize that energy and turn it into useless carbon dioxide and carbohydrates. Manna mines could be created but not fuels.
[Answer]
The Industrial Revolution wouldn't have occurred as it did without philosophical and political changes having occurred a few centuries earlier. Before those changes, Europe was much more decentralized politically and industry was in general controlled by the Guilds. The point of the guilds was to ensure adequate skilled work for all craftsmen of a given trade. This resulted in a basic degree of prosperity, more equitably divided across the society. The guild system did allow for new techniques and ideas, but they spread more slowly because the understood purpose of labor and craft was not to acquire wealth for oneself nor to advance technology, but rather the purpose was to provide for material needs, some degree of self-fulfillment and cultural support.
The abolition of the guilds allowed powerful people to gain wealth and control over industry and politics. It's noteworthy that the level of prosperity of the working man in 1545 wasn't reached again until 1945 with the post-war prosperity boom.
So for your story, if you have a deeply-rooted cultural philosophy which emphasizes other ideas above advancing technology or gaining wealth, ideas such as cooperation, mutual support, environmental concern, individual liberty, etc, it could make industrialization unlikely because it would require massive philosophical changes to be accepted.
[Answer]
# Labor is cheap enough; new machines are expensive
Something to think about... records from the Great Library in Alexandria, Egypt, show that "industrial" devices such as steam engines were not only theorized, but constructed. However, because the cost of labor was very cheap in Egypt (which was mostly due to the Nile being an amazing food source and transportation network), there was never really any need to supplant human labor with machine labor. Although we can't know this for sure, since most of the records from the Great Library were burned down, we can speculate for the purpose of your story that the elites of this pre-industrial society foresaw the social and economic upheavals inherent in such a new system and sought to prevent any change that could potentially harm their social status.
Which could potentially lead to an ideology that believes...
# Only things built with human hands matter
Ruins of the ancient Mayans are all the more impressive when considering that the Americas had NO draft animals. That meant everything had to be done with human hands and feet. No oxen to till the soil, no horses to ride from A to B. Although they did understand basic innovations like the wheel, the Mayans believed that human effort created real value, and it was integral to their religion and way of life. They believed that the gift of Creation from the Gods was accompanied by a "Blood Debt," which had to be repaid throughout all their lives (and often through death by conquest or sacrifice). They were able to create fantastically accurate mathematical models (including the use of zero! ZERO! The number that eluded even the smartest of the Greek and Roman philosophers!), but they still chose to build their impressive cities and towers by hand.
Really makes you think what human beings are truly capable of.
[Answer]
An interesting thought might be to eradicate tea from your world. Some historians think that tea had a pivotal role in making industrial revolution possible. Factories had long and demanding working hours and so after tea became available to everyone, the caffeine in it helped workers to get through a shift. Another - more important - aspect of a high percentage of the population drinking tea was its role in preventing mass pandemic. Since people boiled water for their tea, they killed most bacteria in the water, and it was the only way to stop a quickly spreading epidemic in a densely populated area.
I don't think you can prevent the start of an industrial revolution without meddling with the world and its rules a lot, but there certainly are ways to stop the continuation of it, mainly health and social reasons.
Link to a source from Alan Macfarlane (Cambridge University) as suggested: [www.alanmacfarlane.com/savage/tea.html](http://www.alanmacfarlane.com/savage/tea.html)
[Answer]
Let's define what we mean by Industrial Revolution. I'm going to say this is a period of time where there was a massive shift from hand production of goods to mechanized production of goods (so things like the steam engine and spinning jenny never being invented).
Do I believe this could be prevented forever? Absolutely not, it would happen unless civilization kept getting reset. Could we delay it for a few centuries? Now, that's possible.
There were a lot of driving forces for the Revolution, and I'm not going to argue over them (because I'm not a historian, I'm a software engineer), but the ones that look the most important to me are an available workforce (population), spread of knowledge, and an increase in social freedoms and economic standing.
## Knowledge
As was true in the Renaissance, the spread of knowledge empowers social change. If you have a society or system that tamps down on knowledge sharing (an autocratic regime or strict religion might work) you can reduce the likelihood that enough people create enough machines to make the revolution happen.
Maybe there's a guild or trade group that restricts such knowledge, to protect their manufacturing. Maybe inventors aren't incentivized to create new things, because any time they do their ideas are stolen and make someone else rich.
## Available Workforce
Revolutions in agriculture and a population boom assisted the Industrial Revolution by providing a workforce for new factories. If most of your population is drawn off for agriculture or military service (or if there's just not a lot of population growth because of disease or a society that restricts how many children you can have) you won't have the labor force to do anything if those industrial processes are created.
## Social Freedoms and Economics
In medieval times, serfs remained on the land of their lord. They were largely not permitted travel without permission, and were tied to the land. This limited the spread of ideas, and also limited the wealth of the lower classes. Why does this matter? Machines are expensive. If there's no captialist draw to owning a machine and making profits from it, there's less chance of it happening. Do you think a comfortable noble, who makes money doing absolutely nothing, will give that money to someone else so they can build a fanciful machine to make goods others? Not when it's cheaper to hire a seamstress or cobbler to make the handful of goods he needs himself (which would probably be higher quality than the machined ones). A rich man might want to become richer, but before the Industrial Revolution, there were other ways of doing it that were more familiar and comfortable.
## The Solution?
My solution would be to have the majority of the story take place inside an Empire with a theocratic and oligarchic elements in the government, such as composing something like the houses of a legislature (e.g. the theocratic side could be something like the House of Lords, while the Trade Guilds could form a House of Commons).. While the Emperor is not directly tied to the religious sect or the trade guilds, his actions are heavily influenced by them. The religious sect has a tight control over the printing of books and manuscripts, and any found without their mark are considered illegal and immoral. The owner is considered a heretic. Religion should be very important to the people, to help prevent revolution.
The Trade Guilds control specialized knowledge over their domains, and tamp down tightly on any inventions or ideas that would hurt this control. They actively hunt for inventors, bringing them into the guilds or removing them as a problem. They pride the quality of their wares (as most of their profit comes from the nobility), so unless an invention improves the quality of the goods, it will likely not be put into production. These Trade Guilds also crack down on people selling finished goods without their approval (but do allow production of "home use" goods, just don't try selling them). Parents should relish the opportunity to send their children into apprenticeship programs, and such programs should be highly selective. Most of the people should be simple farmers.
The final key is preventing revolution. This Empire is heavily xenophobic, and is surrounded by weaker kingdoms of different cultures. Every few years, the Empire will attack one of these kingdoms (or be attacked by it). Depending on your technology scale, these could be anything from long, drawn-out medieval sieges, where thousands die from disease and starvation, to gun-powder era battles where thousands die from grape shot and the like (a lack of an industrial manufacturing base would mean capturing enemy equipment might be very lucrative. If you can't mass produce cannon, capturing your enemy's might be a good thing).
Finally, the Emperor should be very kind and generous to his people to prevent revolution. Host festivals and games, help the poor, have a pension plan for the military veterans, etc. The xenophobic part should help a lot too, because social revolution is less likely when there are enemies at the gates.
[Answer]
Considering that the world history **did** see destruction through earth-quakes, plagues, wars and so on and the industrial revolution still happened, that is probably not the way to go.
If you look at the preconditions, the revolution was the end of a long list of mechanical improvements over many centuries. You could certainly **delay** it considerably, and slow it down so much that it won't appear as a revolution in history books by taking away coal, steel and other essential parts of early machinery. But burning wood in iron steam engines works as well. It will just be less efficient, making the whole process a lot longer.
So you **can** change history so that there was never an industrial revolution, just a slow, constant process eventually leading to an industrialised world. I doubt you can keep a world in a pre-industrial development forever without some serious interventions.
[Answer]
I don't think that the industrial revolution - or some version of it - can be delayed infinitely.
The problem you are facing is something i saw descried as "steam-engine time", which describes the time in the progress of mankind (or a sizeable subset thereof) where every knowledge you need to invent a steamengine was readily available.
I don't think it was feasible to prevent progress completely, and while you may remove mineral oil and coal (simply have bacteria breaking down trees a lot earlier and oil nor coalhappen, more or less), but there are other forms of energy. You could still burn charcoal in your steam engines, and bioethanol in your internal combustion engine. You might remove iron, but steam engines can be made from brass or other metals, too.
Granted, that will slow down your industrial revolution, but it won't prevent it.
Electricity was discovered at some point (you may remove amber and cats from your world to slow this discovery down, but it will be discovered eventually, although what would be the point of having a world without cats?), and after that someone will eventually come up with the idea of hooking up a generator to a windmill.
If steam engines for some reason were not feasible, you would get a much cleaner industrial revolution, but it would happen nonetheless.
So, unless you change your setup beyond recognition, i think the answer is
**no.**
[Answer]
A few ways to slow the arrival of the industrial revolution:
1. **Keep the population low.** Technological advancement is accelerated by scale. This could be done by cultural or physical means, for example the edible vegetation could inhibit reproduction.
2. **Keep the population dispersed.** Small groups of people will advance much more slowly. This could be motivated by contagious diseases or scarcity of food.
3. **Increase the difficulty of organization, and decrease the motivation.** For example, disease is very common making social organization difficult, but food is plentiful making it unnecessary.
4. **Lack of good choices for domesticated animals.** This was the first step in organized production. In "Guns, Germs, and Steel" Jared Diamond makes this argument for why European industrialization was ahead of Native American. That's a worthwhile read on this topic in general.
Running some of these together, perhaps this is the second time around. An advanced civilization consumed all the easily accessible coal, oil, and other resources and then collapsed. Possibly they made the best choices for animal domestication extinct during their collapse.
[Answer]
Id say that the **ignorance** of people can put off any development in any age.
**As Ginasius said: An early Industrial Revolution needs cheap energy.**
In order to remove this, ignorance of it's importance is enough for people to ignore it's importance or willing fully deplete the resource before they learn to harness it properly.
**Easter Island**
A good example of how ignorance stopped a society from developing is the history of the Easter island. When the Polynesian natives first arrived there, the island was covered in trees, and the eco system could easily support the them. For religious purposes, they harvested the trees for transporting the big heads to the coast. The extreme deforestation caused by the people devastated the ecosystem. At some point they must have had a single tree left on the island. And they cut it down anyway. Their civilization never really recovered from it. It went as far as reducing the people to cannibalism in some instances.
**Chinese civilization**
When comparing the European development to Chines development, you'll notice that China fell behind in the industrial revolution. The reasons why this happened are because of very complex things, that are best explained in this article: [Chinese industrial revolution](http://voxeu.org/article/why-china-missed-industrial-revolution). One of the points that is being made in this article is that China did not have access to colonies the way that the European countries did. You could argue that when Europe started colonizing the world, China was very capable of doing this as well, but for some reason never did.
[Answer]
The current COVID-19 pandemic suggests a mechanism. A sufficiently contagious and deadly pathogen could prevent larger groupings of people from forming stable societies. The recent large outbreaks of Ebola virus disease provide similar examples as population sizes grow, the possibility of severe epidemics increases.
Smaller groups would continue to survive in isolation, but any attempts at communication from larger gatherings or permanent habitation would result in an outbreak that would return the population back to the pre-industrial state.
This could be repeated until a form of remote communication with sufficient incentive to drive development could be managed as desired.
An alternative mechanism is a sufficiently complex solar system like the one in Jerry Pournelle's [Janissaries](https://en.wikipedia.org/wiki/Janissaries_series) where predictable, if unlikely, orbital mechanics trigger reversion back to a tribal society periodically.
[Answer]
If your **world is governed by a religious regime** which keeps the folk dumb and dismisses any technical progress and science as witchcraft, which gets destroyed and the creators are silenced.
Something similar Christianity did(on purpose or not) in the Middle Ages in Europe which is known as "the dark age of christianity". Some critics say, it delayed the technical progress of humanity for a few decades and as technical progress is growing exponentially, we would be now way more developed.
The Problem with this approach is that one day(eventually some millennia but most likley not) the people will succsessfully rise against the regime/religion and smash it what causes the end of your delay.
[Answer]
I do not think so unless there was some major things lacking in the world.
These are some points for why:
You could technically make a steam engine out of "precision" pottery and a good glaze the piston, wrist pin, connecting rod, and crank could all work like this using that glaze and some good lubricant to keep it all spinning happily. The piston would use a leather wrap to seal against the glazed cylinder walls. This is possible if you went to the extreme and said there were no hard metals on this earthlike planet.
Unless there was a complete lack of competition someone would want to get an edge on producing more of x cheaper than their competitors. This drives innovation which maybe were out clay steam engine is invented from. Would the people living in the information age on this planet call throwbacks to this era clay punk, pottery punk, ceramic punk, or glazed punk?
In a earthlike world any species that does not try to get a leg up will become evolutionarily irrelevant and eventually succumb to other individuals who compete for resources. Unfortunately this is why we can't have a proper star trek society yet.
conceivably the world could simply reject it as a taboo or religion but someone will eventually eat the apple and have a leg up on all the believers leading to more people peeling off from the herd and it will snowball from there.
you could have the intelligent species be unable to build or use tools as in no hands still could conceivably use mouths but you could always pull a page from the star control universe and make them similar to the [slylandro](http://wiki.uqm.stack.nl/Slylandro).
[Answer]
**Logistical barriers could prevent it.**
You can power a factory with a waterwheel, and make some product by the millions, but if you cannot sell it by the millions you will not recoup your investment. You need either a huge nearby city or the ability to send your goods significant distances and still be cheaper than hand-made produce. And you won't see many huge cities that aren't trade hubs.
Rough seas can put a pretty hard damper on trade. If there aren't any large, fertile areas supporting enough people to justify a canal network, it might never be feasible to build a factory.
[Answer]
Iron is quite common because it is [common byproduct of star development](https://astronomy.stackexchange.com/questions/2231/why-is-iron-responsible-for-causing-a-supernova). Making iron scarce will mean your planet is lacking [inner iron core](https://en.wikipedia.org/wiki/Inner_core), which creates magnetic field which prevent radiation to kill life on Earth. So on a planet with no magnetic core, life might not be possible. Or life would have be different (like: underwater only).
So if your intelligent life has to life under water, they would have hard time to get fire! Water surface would be outer edge of their world, and bigger obstacle for expansion than is stratosphere for us.
[Answer]
The industrial revolution was not a given, there were several philosophical and geographical circumstances that made it possible. If any one of them were absent, we might still be working on the family farm and in bed after sunset.
* Enlightenment, leading to a humanistic reinterpretation of religion and individualism
* individualism, which lets you try something new
* History of herding and wheat farming (promoting individual thought and action) instead of more cooperative and conforming rice farming cultures
* Rule of law
* Large nation states
* capitalism, making money available to borrowers at interest and risky ventures highly rewarding to the inventor
* Coal (cheap energy source)
* Iron ore
* Intelligent, educated, wealthy people with free time
[Answer]
## No, you can not
There are lot of things you can do to slow the advancement of technology, but every engineering problem has many solutions; so, taking away Option A only means you need a little longer to figure out how to meet your goal with Option B or C or D...
The only thing that can stop technological progress all together is not having a written language. As long as people can preserve their ideas and inventions for others to follow up on, technology just builds one discovery upon the next. But if you take away record keeping in all of its forms, then you make all knowledge volatile and harder to share with more than a few people. In this way you could get stuck in the stone age for millions of years as our ancestors did, or perhaps another pre-industrial period if your people are clever enough with oral traditions, but not clever enough to write things down.
However, any species like humans that is capable of abstract thought and driven to invent and share knowledge will eventually recognize their need to record that knowledge. Written language was independently invented in several places throughout the world whether it be pictographic, phonetic, or a system of knot tying. Even blind people have figured out braille; so, just making a simple change to human anatomy probably won't do it either.
The best you could do is put a hurdle in mankind's neurological makeup that simply makes writing an inconceivable notion, but even this will only be temporary at evolutionary time scales. Given enough time, a tool using species will be selectively more fit based on their capacity for abstract thinking. Selecting for abstract thought will push a species in the direction of being well adapted for literacy.
[Answer]
**Avoid situations where labor is expensive**
Epidemics, famine, flood, and other disasters may reduce the labor pool that people are looking for substitutes for it. The Black Death was particularly impressive in that it was continent-wide. Small disasters may be compensated for by having immigrants from more populous regions move in -- perhaps by plan. Which leads to another factor.
**Avoid political fragmentation**
There were steam engines and water wheels in the Roman Empire, but they were not put to massive use. The plentitude of slaves hindered that, but another issue was that they wanted to keep the slaves busy, and they did not have to worry about what another powerful nation would do with the machinery. Political fragmentation facilitates an industrial arms race.
Geography helps there. If the rich farmlands are joined by rivers or sea, so that transportation is easy, and the hinterlands are poor and do not support settlement, a unified government can arise and remain more easily. Then it will be more concerned about stability than competition.
] |
[Question]
[
I'm constructing a world where the humanity had to **migrate from land to water somewhere in antiquity**. In this world, humans are living on seas and rivers. They live both on pier-like and other fixed platforms near the coast as well as on rafts strung together into larger settlements offshore. Fishing and sea-plant farming (algae etc.) are the main sources of food. Ships and boats are pretty much the only means of transportation.
The land still exists (topography is the same as of the real world) - no "Water World" scenario. However, humans only visit it for brief periods (several hours, maybe up to half a day) and only to hunt/gather/acquire wood and other land-only resources. There are no permanent human settlements on land. Obviously, this makes certain activites tricky (land farming, mining, heavy industry) but the technical consequences will be deal with in a [separate question](https://worldbuilding.stackexchange.com/questions/61212/what-would-be-the-consequences-of-humanity-migrating-from-land-to-water).
Other life on land exists more or less unchanged (some modifications are allowed to enable a viable answer but I don't want a mass extinction of land-based life).
My question is: **What event (can be sudden or gradual) could cause such a migration happen?**
One caveat is that the event must be global (or eventually global) so that humans all over the world are affected and move their lives to water independently and without communication.
Several thoughts of my own (ideas and associated problems):
* *Predators*: Humans in real world are apex predators primarily due to the highly developed intelligence and social structure. If a smarter and more dangerous predator has evolved on land, why hasn't it taken to the sea to pursue its prey?
* *Superstitions*: No actual monsters on land but tales of such passed from generations are preventing people from returning. If so, how did these originate in the first place? And, given human nature, what would prevent people to go against the "wisdom of the fathers", settle on land and eventually bust the myth?
[Answer]
**1. Irregular geological / tectonic plate activity** - Perhaps at some point mantle became unstable resulting in frequent earthquakes. These earthquakes were small scale but unnaturally damaging to the human settlements. Imagine deep fissures opening up randomly in the heart of cities, small lava eruptions that open and close without a warning, EM flares coming from ground frying electronics, disrupting human brain/hearts and what not. But all large water bodies are completely free of it because water absorbs it all so humans gradually moved to seas/rivers. As for animals, they suffered from losses as well but eventually adjusted and thrived with humans gone. This satisfies your requirements of people living on water and not going inland for very long durations.
**2. Post-apocalyptic world** - Let's say human population keeps increasing eventually to the point that water bodies become viable real estate. It becomes commonplace for people to live on boats and large cruise boats type of structures are common as apartment complexes. Now, cause an apocalypse on land that makes the water settlements far safer than land. Perhaps it was a super-bacteria/virus that thrives in concrete/asphalt but not on lighter plastics/woods used to create the houses on water. So, humans didn't "migrate" to water, they were already living there and then something happened on land that resulted in only the water settlements surviving.
**3. Zombies** - Zombies can't swim. Humanity can't beat the zombies and must start living offshore.
**4. Predators** - Let's imagine the movie "Jurassic world" as what its name suggested instead of being a working Jurassic park. Dinos have either fully integrated in the society (Dino pets, Dino powered lawnmovers, Dino egg benedicts) or thriving in relative secret in jungles and something causes them to become the apex predators (human partial extinction due to plagues, wars etc). Sounds outlandish but dinosaurs can be enhanced or replaced with anything else as long as it can't survive in water and doesn't exterminate all other flora and fauna. It could even be as simple as triffids or Alzheimer's like symptoms inducing plant/microbes.
**5. The last ship** - In this scenario, an apocalypse has happened and only the ships out very far away in the oceans have survived. The land is not livable except by plants and small animals, so they restart the human civilization on water.
[Answer]
# Land is barren while the seas are bountiful
Desertification spreads across the lands while the seas remain untouched by the scourge of the Gods. Those who make it to the shores are pushed out to the seas to find a new life. The many fish and other animals of the ocean provide for a hearty diet, if a bit difficult to catch, as people have to give up their hairs to create nets.
As time goes on the wooden boats of old begin to decay, and in a twist of luck and fate, a small fleet comes across a decaying sea predator corpse on a nearby shoreline. Before then, such predators were the stuff of nightmares, as each kill only attracted more to the slaughter. But the waters were calm that day so the fleet came ashore to examine the corpse. They discovered that the bones are both light and strong, perfect for creating new ships. The sinewy muscles can be spun into a powerful fiber that defies decay as long as it remains away from the air, and the fat can be boiled into a paste that holds everything together. In addition, they find that glands in the brain produce a powerful odor that turns other predators of that type docile, making them easier to kill.
After that fateful day, the small group of survivors use their newfound discoveries to create an impressive fleet, and within a generation they go from being desperate survivors to hardy conquerors.
(This deals more with the sister question but it was difficult to do one without the other and decide where it belonged best.)
[Answer]
# Disease
It's going to be the wealthy and the already mobile who lead the way. They're going to try to stay safe in sealed enclaves but once a plague goes global the only way to truly quarantine yourself in a controlled environment will be to go to sea.
A disease carried by just about any mammal but mostly only affecting humans would drive people off the land to stay safe. Only the suicidally brave or immune would risk going back to land to gather resources.
[Answer]
**There was an AI war with a very interesting quirk**
Picture that roughly 50-100 years before your scenario, mankind was at it's peak. We had vast sprawling cities, booming industry, and we were just beginning to rely on intelligent machines for everything; civilian, industrial, and unfortunately for us, even Military. Machines were everywhere, there was roughly one Mechanized intelligence for every 2 humans on the planet.
One of the major powers aimed to capitalize on this and started development on a sort of "mega-weapon" super virus with the goal of converting all the AI of a rival power to their control. However, they never got the chance to use it, as a group of radical Eco-terrorists managed to get a hold of the virus and then hastily modified it to use for their own agenda. The result of this patchwork modification:
**All Intelligent Machines are compelled to protect the land from mankind**
The eco-terrorists released this virus and it spread like wildfire among the worlds machines. We lost the ensuing war, and modern civilization collapsed. During the conflict however, Mankind noticed their one sanctum was the water. The machines one-track minds and extremely literal adherence to their programming meant that they did not initiate aggression towards humans that were quite literally "not on the land".
Mankind had no choice but to start rebuilding society off shore. At first there were countless efforts to try to re-settle the land, but any time the machines found out the location of a new settlement, they would attack like antibodies to remove the human infection. After enough failures and enough lost lives, mankind finally learned it's lesson and stopped trying.
Decades later, the land is still seen as a very dangerous and taboo place to man. Nature has done quick work to reclaim much of what man has built. The machines still silently patrol the vast wilds of the old cities, and they might even be one day viewed as gods as the knowledge of the past is gradually lost. Soon, only the bravest of hunters will venture into the monumental ruins of man to look for supplies and food, most do not return.
[Answer]
Two other options which haven’t been mentioned yet:
**No clouds**
Due to some particles in the air (maybe a biological weapon?) rain happens almost instantly as soon as water evaporates. The only remaining sources of water are large lakes or oceans. This would also mean that all land turns into deserts except close to the water.
**Radiation protection (only makes sense if they also live underwater)**
Water is a pretty good shield against UV radiation and gamma rays. Maybe the sun went haywire and is regularly emitting huge bursts of radiation. The only surviving life forms would be in water and living under water would be a good way to protect against it.
[Answer]
**Termites**
Consider the question: [If the insects declared war, who would win?](https://worldbuilding.stackexchange.com/q/22729/2044)
If all termites in the world would cooperate to get rid of humans, they quickly might. Except that termites can't swim. We can't kill all insects, but with large anchored rafts, humans are quickly forced to learn growing sea vegetables as fish alone is not good enough.
[Answer]
An intelligent predator living in groups (perhaps Neandertals? Large dogs? Monkeys? Bears?) that got an advantage over humans requiring them to fortify themselves in such places.
Switzerlands lakes have many human communities that lived as you described (as protection from other humans). Aztecs at least partially become supreme in their area because they were difficult to attack although vastly outnumbered when they first started.
I would think humans would have fought for the land and lost, so now remnants have moved onto water where they can survive, eventually developed technology that gave them a clear advantage in that arena, going onto land only in defensive groups prepared for fight-or-flight. Then attrition keeps their numbers down. Those groups who retreated to mountains and forests were all overrun over time etc,. Except for one group with an exceptionally well endowed and scantily clad chiefs daughter (considering how cold the mountain is) who the protaganist eventually hooks up with.
[Answer]
## Allergies
Through some mutation, we all developed severe allergies to pollen and various plant life. Heck, some people are allergic to grass; maybe we all got that allergy too. You might say this wouldn't stop people from living on rocks, but we wouldn't be able to (easily) farm plants or animals. The easy way out is to move to the water.
This gives you a nice excuse to keep people away from land and can explain why people can only visit it for a short time: maybe only the people who have less severe allergies can venture out, and only in protective clothing and face masks. Plus you don't have to change the current landscape, since it's strictly a human change.
**Second thoughts:** I suppose this wouldn't stop people from living *in* places like the desert or the tundra, so this would only really work if you make the allergies cover nearly all plant life and perhaps most mammals (like dander allergies). This way, it would be more difficult to hunt animals in "hospitable" environments than it would be to just move to the water and fish. People who live in arid regions still rely on agriculture, so if everyone is allergic to plants, they'd be living in the desert and yet still need stuff imported from the sea. There could be a pressure for people in these environments to move closer and closer to the sea to make trading easier until eventually, they just live on the water. There's nothing for them on the land.
[Answer]
I'm hard pressed to find a reason why humans would abandon land completely especially if they are as ingenuous as humans are in the real world. Depending on how technologically advanced your humans are, I imagine that they could figure out a way to deal with predators with lower intelligence than us--just like we have for every real world predator. Similarly **disease**, **radiation**, **solar activity**, and **tectonic activity** offered by other answers would *still affect humans living on the water*.
**An intelligent predator that cannot swim/create naval craft**. This might include zombies, but you're gonna have to think long and hard about what it is that discourages these creatures from coming into the water.
**Global climate change.** This I think is the most realistic option. Perhaps the only arable land is on the banks of water on your world, and this is where the humans get their supplies.
**Scorched Earth.** This is farfetched, but maybe a comet or series of asteroids happened to hit land all over the Earth, resulting in the elimination of most life, removal of arable soil down to bedrock and perhaps causing shock-metamorphism in much of the land. Now people *could* live on land, but there would be no reason for them to if they couldn't farm or hunt--so they may as well live on the water or along the coast where they can farm fish.
[Answer]
We can break the options down into two categories; depending on the general feel of your world, a mixture of answers in both categories could be suitable. So, those categories are *Land push* and *Water pull*.
**Land push** - Humans are being pushed away from the land
This is well covered by the other answers here, however, as the land is largely the same then we'll likely need purely human social constructs to keep people out. Humans are largely only afraid of other humans so an additional option could be societies in which **only the Elite are allowed to live on the land**. Lots of very dark routes there - maybe peasants are hunted as some kind of awkward sport. Nice.
**Water Pull** - Humans are being attracted to water
This hasn't been mentioned so far; Focusing on this positive category completely changes the feel of your world. Essentially, what's making water so attractive? A classical example is that it has **healing powers**; maybe humans used such powers so often that they've become **entirely reliant on them** - it's something that could grow over time too.
Similarly there could be social constructs here - people simply **don't know how to do anything other than fish**; maybe literacy is limited (or simply doesn't exist) so sharing skills and techniques is a verbal only process. Trade doesn't work too well though. Other helpers on this more general category are asking yourself questions such as *"what would make me move to the coast today?"*. Then consider how that can be amplified.
[Answer]
Dolphin and whale skin needs to stay wet, or it cracks. Our skin has to stay pretty dry, or there are infection issues (trench foot). Something that changed human skin to whale skin would pull towards water.
Something that made that valuable would explain why it wasn't cured. Some complex seaborne microorganism?
This is kind of sexier than I anticipated. Which never hurt a story, IMHO.
[Answer]
For a migration in the pre-historic times:
1. The easiest source of food is available from a ship, but not from the shore
2. Some sea animals that can be easily domesticated, and are really good at sea-land warfare (giant turtles?)
If the seas provide easy food and "livestock", instead of pre-historic shift from hunting to farming, there'd be a shift from hunting to sailing. The sailors would occupy the highest society ranks, inventors would work on improving the ships, the sea food would become the main food source.
After a while, the ships would get big enough for raiding the land settlements - they can attack with the warturtles, or "besiege" the land-dwellers, destroying their ships and cutting them from the sea food. Eventually, the land settlements would be colonized by the tribes of sailors.
As the sailing tribes acquire way more resources than the land colonies, they invest more in the technology development. Eventually, they reach the point where they don't need land colonies to survive. The land-dwellers either join the sea-dweller civilization, or are constantly looted by the bypassing ships and eventually destroyed.
[Answer]
This is documented in the history film [Tremors](http://www.imdb.com/title/tt0100814/) and its many prequels, sequels, and spinoffs.
On a more or less serious note I cannot think of anything that would force us to stay on the water with only short land expeditions especially considering one option is to live on docks which means land based predators could easily walk out on docks along with insects. This would also mean we can be reasonably close to shore and so land based poison or radiation would not be a factor either.
There is of course unnatural phenomena such as the land is cursed and will kill you if you are on it for 24 hours but I do not think this is what the OP is asking about.
natural disasters wouldn't be the reason since it is much more dangerous to be next to shore on a dock with an earthquake which can kick up a title wave especially when it is a `<h1>` title wave. Lightning would be no good same with tornadoes and hurricanes.
[Answer]
Sort of a cross between **Trilarion**'s "[Poissonous [sic] insects](https://worldbuilding.stackexchange.com/a/61232/7290)" and **limitlessinfinity**'s "[Allergies](https://worldbuilding.stackexchange.com/a/61231/7290)" is the idea of a
## Toxic Plant or Fungus
or a toxic microscopic symbiote (think [mites](https://en.wikipedia.org/wiki/Mite)) that is ubiquitous and which reacts over time with humans when they encounter it. I'm thinking of a world strangled with some kind of poison ivy, for example, to which naked apes with their exposed skin are susceptible, but animals with fur are not. Or a fungus like athlete's foot that will grow on people's skin from ubiquitous spores within hours, except that contact with saline water kills it.
That need for salinity in the latter proposal would slightly change your original vision, because people couldn't live inland up major rivers, but only in coastal bays and marshes, where the salt penetrates landward, or in the rare pockets like Salt Lake and the Dead Sea, where inland seas dried up and lost contact with the land. Maintaining contact with / rediscovering human tribes that had been nearly or completely isolated when their salt water bodies separated from the global seas would give you some fun plot points, too.
[Answer]
A mutation in the inner ear (related to balance) that when extended periods of time are spent on 'solid land' it leads to nightmares, headaches, and generally unpleasant unhealthy situations.
They found that spending a fair bit of time on a floating structure was enough correct the imbalance. Scientific research has shown that there is a difficult dance that can be done to counteract the problem, but it is rather impractical as it would take several hours of effort. The simpler solution was to live on the water and go about the daily tasks.
Further thoughts: It might not need to be debilitating, but just something uncomfortable. People could live on land, but their overall health and well being are improved living on floating structures. Or perhaps it wasn't initially so bad and over generations it has gotten worse and now if you spend a few days on land you develop "land madness". There is a lot of wiggle room to fit your need.
[Answer]
**Unfortunate climate**
Land mostly consists of desert, mountains, ice or swamps
**Poissonous insects**
Is not really a predator but may threaten your offspring unless you go somewhere where you can keep the insect population under control (on the water surface).
**Huge weather irregularities (thunderstorms)**
You need to escape them constantly and for example going once around the earth you can only do on the water. Maybe you even have to dive with your plattform when a storm comes.
[Answer]
Maybe aliens will visit earth and will teach how humans can be genetically modified so that humans can breath underground and never visit us again.
And this thing becomes a cool thing and everybody wants to live underwater and gets genetically modified.
After few years this genetic modification would affect them creating disease like asthma if they breath through air making difficult to breathe in air.
And it would be comfortable to live in water.
[Answer]
**Worms**
Well that or any other form of burrowing creature, a subterranean hunter which can't swim and can't stay above land for long but is lethal when it surfaces.
Trips to the land would require constant vigilance for wormsign/molehills etc
[Answer]
**Luke Briggs** sort of made the point I wanted to, however I'd include the recent bout of political uproar as inspiration. As mentioned, humans are their own worst enemy, and so I believe wide-spread panic, fear, and propaganda could also be a reason that drive people to live near open waters, then over time almost exclusively turning to water-based abodes. Considering politicians and people with vested interests will lie their way to obtaining their goal, this doesn't even seem like too far a stretch. I'd suggest that this sort of huge, socio-economical change would likely not fit well with a majority of people, but perhaps smaller groups of people would leave the skeptics, then stronger efforts to spread the propaganda may result in larger quantities of the population to move to the shore.
Considering how humanity is moving forward, some analysts mention a population crunch could begin wiping large amounts of people from the Earth, and so a mass-event like this could instil enough fear and confusion that they will likely listen for their leaders instruction. This situation could also be a false-flag operation-- the government (or even a secret global community) could conduct a mass-execution situation, then using the fear found from such an event, suggest people move to live on or near the sea.
As far as avoiding fantasy-type elements, like aliens and robots, I feel as though this is a possible solution that won't turn readers away, unless they're not a fan (or have experienced overkill) of recent politics.
[Answer]
**Spore-Like Virus**, but thrives in the absence of water. Limited exposure could be allowed, but if the ground is covered with this stuff, stepping on them causes them to become activated and airborne. Since the air has some moisture, the virus isn't able to travel too far, making large bodies of water a natural safe-zone.
Various animals can survive due to being able to frequently go in and out of water or just lick themselves. Living high up in trees could benefit as well. Salamanders or any animals with mucus covered skins could thrive. Could just be dangerous to mammals.
Some form of decontamination may be necessary, but that would just be a quick dip in the water.
[Answer]
**[Genetic Warfare](https://en.wikipedia.org/wiki/Biological_warfare#Genetic_Warfare)**
You could be living in a period post a serious genetic war.
1. **Genetically modified resources**. A nation, or multiple, could have figured out how to genetically modify a widespread resource to be harmful to humans. Several nations could have even targetted specifically each others primary races and thereby forced each other off the resource plentiful land where we humans have built basically all of our developments.
2. **Genetically modified humans**. People, whether they be nations or malicious individuals could have been targeting the water supply for dozens of years causing genetic defects in the next generation, such as severe allergies to certain wide-spread flora, like grass, or an insect like flies, or perhaps numerous things, or perhaps even more likely, we never figured out what exactly we're allergic to.
This would mean that parent's would take to the seas to save their children from their severe allergies and would allow a period of time where adults could be land based, and any setup required (such as lots more boats, supply depots, or some other features your people depend upon) could be created.
[Answer]
A tyrannical regime which spans the entire world. It is headed by the descendants of the world's most notorious pirates.
They hate landlubbers. Being a landlubber is punishable by death so people are all forced to live on the high seas.
People can still get amazing things on land but there are loads of drones which hunt down and kill them.
All permanent settlements and infrastructure had been bombed out when the pirates took control because they are necessities for landlubbers used to modern comforts.
2% royalties please.
] |
[Question]
[
In my story, a planet of low-tech natives in the midst of war are abruptly brought into contact with a much more advanced empire. There are many historical precedents for this kind of event, and occasionally the natives are able to fight back. Now, in order to mount an effective defense, these natives must have space vessels.
My question is, how basic can I make the natives' tech and still have them be able to create spaceworthy vessels? For example, *we* build our space vessels with steel. But could it be done with bronze? We propel our spaceships with highly advanced compounds, but could it be done with gunpowder?
Edit: There's no need to take my examples literally. I was not seriously considering the idea of a bronze spaceship, it's just an example of the kind of low-tech making-do I'm looking for.
Edit: So as to help our natives along a little bit, we'll say this planet has half of Earth's gravity.
*What technological advancements are **absolutely necessary** for travel into space?*
[Answer]
About the minimum you'd need is what the Germans had available to them during WW2.
Their A4/V2 rocket was nominally capable of reaching space (though not of orbiting) and they were working on designs of a functional spaceplane that would fly a suborbital trajectory to the US to drop bombs there and then skip over the atmosphere back to Germany.
More capable rockets were under development that would have been able to launch men or satellites into space (though that was not the primary consideration at the time) in the form of the A9/A10.
As to fuels, liquid oxygen + kerosene does the trick just fine. You don't need "advanced chemicals".
The biggest problem would be navigation and creating and maintaining a pressure capsule and a breathable atmosphere within it.
For navigation, someone with a slide rule and enough paper and time wouldn't need much more than a sextant and maybe a telescope.
The biggest problem with the pressure capsule is making air tight seals that don't fail in vacuum. Plastics, artificial rubbers, and things like that are the most used for that, maybe other things can work as well.
And then there's the problem of maintaining the breathable atmosphere on board. Spacecraft use CO2 scrubbers which need some knowledge of osmosis and processes like that to construct. If you go longer, you might need a means to reduce CO2 to oxygen and carbon so you can reuse the oxygen for longer.
Again, nothing we couldn't do in the 1940s. Bronze pressure vessels can probably work, but the mass may be higher than a comparable internal volume in steel.
[Answer]
**It's more believable for them to steal a ship**
Any one particular technological innovation stands atop a mountain of discovery, innovation, experimentation, experience, and knowledge. The size of that mountain is considerable. Successfully putting a human in space depends on a breathtaking amount of technology, from spacesuits to rocket engines, from electronics to heat absorption, from chemistry to materials science. The hunt for rocketry probably started with the Chinese thousands of years ago. It matured with the Nazis decades ago. It's not exactly a daily event today, despite jaw-dropping advances.
[Jules Verne](https://en.wikipedia.org/wiki/From_the_Earth_to_the_Moon) might have been the first to suggest sending a shell (e.g., from the barrel of a gun) into space. [Space.SE](https://space.stackexchange.com/questions/815/can-gunpowder-get-you-to-the-moon) answered the question of whether or not that was plausible. Their conclusion was if... if... you could scale the physics, it would take over 14,000 Kg of gunpowder, and the g-force would turn humans into a thin pink paste on the back of the capsule.
And that's assuming the bronze didn't collapse, melt, warp, or anything else, which it would.
Low-tech natives would lack everything from the research base to solve the problem to the manufacturing base to produce the materials needed to achieve the solution.
So, for practical reasons, the answer is "it can't be done." Your natives would need at least 1930-1940 tech just to understand how to ask the question.
---
**Edit** To resolve the OP's concern: In reality, the first man in space was April 12, 1961. Assuming the low-tech natives had access to information that we had to discover the hard way, it's plausible to believe the achievement could have been done with 1940s technology, had all the answers been provided. If the natives simply look at a space ship, then the earliest tech they could possibly get away with is 1960s. A different answer would require knowing (a) what the current tech of the natives is and (b) what technological insight they have access to other than visual (e.g., documentation).
[Answer]
**What technological advancements are absolutely necessary for travel into space?**
1. A good understanding of classical physics. By this I mean that your natives would need to understand how to measure gravity, how gravity interacts with objects in/outside of the atmosphere as well as how force/mass/acceleration work together.
2. Some sort of material capable of remaining quite airtight and heat resistant in space. This wouldn't necessarily have to be perfectly airtight (air leaks are no where near as devastating in space as sci-fi would have you believe), but it would have to be good enough to keep most of the air in and most of the heat out when re-entering.
3. A propellant of some sort. It takes a lot of energy to get into space. ~90% of our current spaceships weight is actually fuel and the fuel we use is pretty close to as efficient as possible for chemical fuel. It's possible with gunpowder, though you would need ridiculously large amounts to get even a small payload into space. This would be easier on a planet with much lower gravity than earth. The formula for calculating the escape velocity is
$$
v = \sqrt\frac{2GM}{R}
$$
where G is the gravitational constant, M is the mass of the planet and R is the radius. If your race understood that equation, I don't see how they couldn't figure out an appropriate fuel.
4. Some other sort of vehicle that is capable of traveling in extreme environments would help. If they already have some sort of a submarine/airplane it would make things much easier for your natives. I don't think this is absolutely necessary, but it's pretty close.
I think that these four things are the most important advancements for space travel. If you have these you can probably do it no matter where else the rest of your tech is at, though it would be incredibly difficult with pre 18th/19th century tech. Having said that, war speeds up development in leaps and bounds so it's not difficult to imagine us with our curiosity, innovation and fearlessness skipping several levels of technology almost overnight if we got our hands on some advanced alien technology especially if our survival depended on it.
[Answer]
Assuming a similar gravity well to Earth, you'd at least need to understand the Maxwell equations. These were first conceived (or at least published in a rudimentary form) by James Maxwell in 1861 and integrate magnetic and electrical forces.
It took around a century for that knowledge to be expanded upon and consolidated to a level that we could build the first rockets capable of getting us to space, and being able to communicate with them (via radio), and while at least a part of that was the will to do so, it is important to note that without integrating at least 2 of the fundamental forces as we understand them (doesn't necessarily have to be electricity and magnetism), the ability to use these forces to generate power and harness it in novel ways doesn't exist. Without that, we simply cannot generate, store or take advantage of the power needs required to get a ship off the surface of the earth and into space.
Add to that the need for communication with the ship en route, and Maxwell becomes even more necessary as without his equations we have no radio, TV or other mass communication capability.
So; theoretical knowledge of the late nineteenth century, and engineering knowledge of the mid-twentieth century. Otherwise, we would have done it sooner ourselves as Man has always been fascinated by the stars.
[Answer]
I would agree with the 1960s-tech assessment: you don't just need steel, you need high quality, lightweight, high strength steel, etc. You can, however, give your natives a leg up in the non-tech areas. One suggestion that comes to mind is an extremely high mountain range that extends well beyond the atmosphere. Not only would this give them experience with airlessness, it would also provide a useful launch platform -- assuming they could move all the required natives and equipment into such a deadly area. But space is difficult and requires a long learning curve -- read up on the ongoing space programs all over the world; even with the knowledge and technology, the secret sauce is experience and perhaps failure.
What about the natives would make them good spacefarers? One example would be if they were squishy enough to survive being shot out of a cannon. This would also have war implications -- if you could shoot an army over a wall, how would fortifications and weapons be different? A plus is that it's not a stretch to start shooting natives straight up; a minus is the plausibility of a body that can survive hundreds of gees.
[Answer]
## Short answer: **yes.**
## Long answer: **maybe.**
It largely depends on the planet they're on, the natural resources and natives readily available to be used in a war, and the full extent of the war they're in. Say, for example, these natives had been long-time trade partners with a larger, more powerful civilisation. Come time for war, these natives could buy / borrow some of these civilisations' tech, without the slightest idea of what is in it or how it works. Then again, any civilisation may be rather unwilling to provide space tech to a group of unindustrialized savages, so that is also a possibility.
Then, keep in mind the planet they're on. One of the fundamental ideas behind space is: once you're in space, it's easy enough to stay there, the problem is getting off the ground. If your little group of natives were on a planet with a rather small gravitational pull, they could potentially form airtight vessels and use the aid of geysers or other such natural propellants to put them into lower orbit.
As for fuel, this is where things get difficult. If they had access to gunpowder, they could use the aforementioned geyser propulsion system to get *into* the air, then once they started to slow down they could blast different segments of their ship off into the planet to gain some minor speed boosts.
All in all, I'd say your natives are kind of screwed; their best bet is stealing enemy tech and hitching a ride to their base and sabotaging it from within.
[Answer]
**Understanding of Flight and Orbital Mechanics**
It is important that our natives understand the basics of flight and orbiting. One of the main setbacks of making it to space in our history was this, and was a problem even after the successful development of liquid-propelled rocket technology. Take Robert Goddard and the Pendulum Fallacy, for example, in which he believed that the engines should be placed at the top of the rocket so that the rocket would hang like a pendulum. Another such example was difficulty rendezvousing with early Gemini tests because of a lack of understanding of orbital mechanics.
**Computers (Bonus, probably not necessary)**
They should at least be able to run simple automated sequences. Controlling everything by hand in the constricted environment of a space capsule is very difficult and requires too many people, which would just add weight. They don't even have to be able to do computations if the pilot is good at math. But just some basic automation that can run sequences.
**Edit:** Computers may actually be unnecessary, according to jwenting's comment.
**Liquid Fuel**
Solid fuel won't cut it, unfortunately. Solid fuels are difficult to control and not as effective for their weight. Liquid fuel is very easy to produce, though. Simple electrolysis of water can produce hydrogen and oxygen, and this technique has been around since the 1700s. Ethanol and oxygen is another good propellant.
**Some Sort of Strong Material**
If we're going to be realistic, the ability to create steel or some other light and strong alloy is a make or break factor. This they could probably learn very quickly from studying a crashed enemy ship.
**Means of Production**
They must also be able to create many of these, and fast. Organized factories will be required for producing ships at a decent rate.
**Life Support (Maybe)**
Just the ability to replenish oxygen for an extended period of time, most likely from a pressurized tank.
**Other Things to Consider**
How big are these planets? It is not uncommon for terrestrial exoplanets to be much smaller than Earth and still in the habitable zone of their star.
What is the history of this civilization? Not every civilization should be expected to develop just like ours. They may have some accomplishments offset. Maybe they've developed spaceships before boats, or maybe they have large factories producing spears. (These are just exampled, I'm not saying they are valid.)
**Conclusion**
I think that the biggest setback is going to be computers. If your civilization already has computers, you're all good. But if not, you're probably not going to be able to learn how to make them by salvaging from destroyed enemy ships, because they aren't easy to understand without prior knowledge. They can probably learn to replicate the enemy ships' material fairly quickly, however, and they could probably also learn plenty about orbital mechanics from them as well.
Stealing enemy ships is likely not a possibility. If we are talking about realistic spacecraft, then the capsule and maybe a lander stage would be all that was left and it would be out of the question straight away. If it was more like a space plane, then the if they speak different languages they will not understand controls, and if there is a password then that's about the end of their adventures.
Overall, if the civilization has come into contact with another that can make these ships, then they should be able to learn from them much faster than they would figure things out on their own otherwise.
[Answer]
In addition to the other answers, there is one component missing. You need some sort of computing platform, and electricity. It doesn't need to be very high tech, at the bare minimum you need the equivalent of transistors. You can't expect to have a mathematician on board calculating course corrections and orbital maneuvers in space with a sextant. The transistor is the single element we could never have gone to space without.
[Answer]
A lot of these answers are saying its not nearly possible for a full spacecraft so I wish to provide an alternative. A way to defend the earth with artillery.
# [The Verne Gun](https://en.wikipedia.org/wiki/Space_gun)
Essentially it is a cannon capable of sending a bullet into space. The idea is from 1865 and with the advent of modern artillery you may be able to do this with WW1 era technology.
This comes with a caveat that it has never been built before, along with being unguided and impossible to launch a human with. Although the [Germans with the V-3 cannon](https://en.wikipedia.org/wiki/V-3_cannon) and the [Iraqi military with project HARP](https://en.wikipedia.org/wiki/Project_HARP) have tried in the past.
[Answer]
Bare-bare, at half earth gravity?
Getting into space is trivial. Surviving in space is somewhat harder. Being space-worthy (navigable in space well enough to fight another vessel) is considerably harder. And returning to the planet alive is essentially impossible.
So barebones means no coming home. No return trips. You go to space and you either capture one of their ships, or you die trying.
Glass-blowing gives you a good airtight vessel, proof against one earth atmosphere. Since gravity is half earth's, the atmospheric pressure is likely to be far less too, so the pressure will be even lighter. Or just make 'em able to survive in vacuum for a few minutes, then you don't even need to be airtight.
Half the gravity means half the escape velocity. Earth escape velocity is 11m/s, so they'd need 5.5. At a bit over 10G acceleration (approx upper bound of sustained survivable for humans) of 100m/s/s, you'd need 55 seconds of acceleration - call it a minute.
How can you get 55 seconds of acceleration? Well, you could launch them along a rail 124km long, but (assuming you don't want their bubble to melt) you'd need to evacuate a tunnel around that rail and put the end of it above the atmosphere.
Assuming you have a mountain that reaches above the atmosphere of your planet, that's totally doable just with glass-blowing technology, of course. Really, really advanced, industrial-scale glass-blowing technology. But whatever.
So, you can make a tube, you can evacuate it, and you can drop someone down it in a glass sphere or capsule, then accelerate them along it at 10m/s/s for a minute. How you do that without them hitting the side of the glass tunnel in their glass bubble and being vented into space at 5500m/s is an exercise for the reader. You could say "magnets" or "rails" but there's no magnet or rail on earth that can withstand that kinda momentum.
Now he's in interplanetary space. He's higher and faster than the space shuttle or the ISS or even the Apollo missions, since he has escaped the gravity well of his planet.
But there was no way to aim that, other than timing to determine where in the planet's rotation he was fired out. But ships don't sit stationary relative to each other. There's no way that kinda ship could ever match velocities with another ship, without also launching with huge amounts of reaction mass. So you most likely need some kinda directional jets, and computers, and so on - a whole 'nother kettle of fish.
So, barebonesiest, you launch him from basically a catapult on a rail, no craft at all, and hand him a fire extinguisher for propulsion.
[Answer]
The main problem of building spacecrafts is the tyranny of the rocket equation. This equation says that the amount of propellant that you need grows exponentially with the speed difference you are trying to achieve.
Bummer is, you need to accelerate pretty hard to reach even the lowest orbits, you need to accelerate by no less than 27000 km/h. Fail to do so, and you fall back to earth. And, due to the rocket equation, you need insane amounts of fuel for this. Just to give you some numbers, here are some stats of the Soyuz rocket and space vessel:
```
Space vessel weight: ca. 7 tons
Weight of rocket without fuel: ca. 19.1 tons
Weight of fuel: ca. 156 tons
```
You see, the whole rocket is basically a big pile of fuel wrapped in a thin layer of steel.
---
What does this mean for a low tech population trying to build space-worthy vehicles?
It means, they are screwed. They need to contain liquid fuels, some of which need to be pressurized, within a container that is only allowed to weight about 1/8 of the total fuel mass. It is quite hard even for us today to build such light-weight structures that are still strong enough, and we have lost rockets as recent as 2015 ([Falcon 9 launch failure](https://en.wikipedia.org/wiki/SpaceX_CRS-7)) due to structures that did not hold up under the forces exerted on them.
Low tech means, you need to include high safety margins to avoid catastrophic failure, and high safety margins mean much more fuel, and much more rocket to hold that fuel. The lower your tech level, the larger the rockets need to be. We need rockets that outweight their payloads by a factor 25, just to get some small payload into space. How big will that factor be for your low-tech people?
Can you imagine your low-tech people building significantly larger rockets than the ones we build today? If not, I'd say, any space-faring society needs to be at least at our level of development in the middle of the 20th century, when we first started sending rockets into space.
And all this does not even include any potential for fighting battles in space...
[Answer]
The bare minimum to get a man into space would be Soviet-level technology in 1961. That's when the USSR put Yuri Gagarin into orbit. Even then, I would not call that reproducible, and as such would not be minimum tech for getting several men up to orbit to do a job (and to get them back safely).
The USSR got ahead of the US, in part, because they were willing to lose men doing it. So it was probably not as safe you'd want.
I am assuming you are talking about manned space vehicles.
[Answer]
Many of the other answers have pointed out that you need airtight seals for the ship. However, that is not the case.
If you want to go super low tech, the hull can be a solid metal container. Before launch, a circular hole is cut into the sphere so the person and any required equipment can be put inside the craft. Then, the section that was cut out can be sealed up and welded shut. When the spaceship returns to earth, the hull can be cut open to free the person inside. No seals needed.
You may be wondering how the environment inside stays livable. The metal ship radiates heat, but the person also generates heat, which makes me think that the heat would be balanced out in the short-term.
As for food, canned food would suffice, provided it was attached to a wall so it wouldn't wack anyone in the head. Water can be stored in a waterskin or a water bottle of course. A couple extra bottles for waste disposal.
The atmosphere would be the biggest concern. To filter CO2, all you need is some activated carbon exposed to the air. To replace the filtered air, you don't even need air tanks outside of the ship. You don't even need air tanks at all. A large balloon would suffice. As long as you have a basic understanding of atmospheric composition and human air requirements, you can even use normal air provided your tank/balloon is large enough.
These methods should help you stretch the limits of how primitive your space ship can be. Good luck.
[Answer]
Here is a wonderful resource from 60's era NASA. It's a long read and quite technical but details what is probably the minimum (and maximum at the time) capabilities for space travel.
<https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19710019929.pdf>
The reason I wanted to present this is because, being interested in the subject I stumbled across this a few years ago and was blown away at the level of technology that had been developed for getting people into space.
First, I wouldn't worry at all about your natives learning the technologies. Societies with lower tech are not any less capable of utilizing higher tech...they simply don't have access to it. But here's the problem. The technologies have to be created using technologies, assuming your natives don't just steal or trade for it. Even today there are advanced places without the technological capacity to produce the very technology they consume.
For example, USA reliance on Russian made RD-180 rocket engines
<https://en.wikipedia.org/wiki/RD-180>
[Answer]
Are you willing to cheat? [Harry Turtledove](http://turtledove.wikia.com/wiki/The_Road_Not_Taken) had medieval Teddybears armed with muskets flying ships no more complicated than an airtight classical Greek trireme. The conceit is that they (and everyone else in the universe save humanity) discovered a stupid simple way to accelerate infinitely for very low power use, and a stupid simple FTL drive.
[Stephen Baxter](https://rads.stackoverflow.com/amzn/click/B00OQRL5JI) has Roman legions flying between stars in giant metal cylinders using alien nigh-infinite thrust engines.
So if you're willing to bend/break the laws of physics (or at least put some magic handwavium ancient alien tech in play) then you can certainly make a story work with savages in space.
[Answer]
**Throw in a little bit of magic.**
As others have already pointed out, flying to space requires WW2 level of tech. However, note the word "to" - most of this advanced tech is needed to take off. Once you are in space, you can fly, literally, in a wooden barrel propelled by fireworks. Space itself is not a harsh environment. You would need a hull that can hold 1 atm of pressure, chemical source of new oxygen (easy), and a way to control the fireworks that propell you. I do not know how do it without electricity while keeping air-tight hull, but electricity of that minimum level has been known at times of American Civil War at least. May be hydraulics? Do not forget heat buildup (coolant system) and radiation ( a layer of foil would do).
So, if you create some fantastic way to move spaceship into the space (magic? Permanent teleport from surface to space? capture single enemy ship to use as a launch system?), then, I think, you could do it with Victorian era tech.
[Answer]
**Want to improve this post?** Provide detailed answers to this question, including citations and an explanation of why your answer is correct. Answers without enough detail may be edited or deleted.
Not much technology is needed.
Here is a story by Turtledove about a space faring, Renaissance level society:
<https://eyeofmidas.com/scifi/Turtledove_RoadNotTaken.pdf>
[Answer]
Give your planet a seafaring warfare history, then as a plot device, adapt submarines for space - the main tech difference would simply be reversing the seals on the hatches so that they resist 1 atmosphere outward pressure rather than many atmospheres of inward pressure. Make the crew from submariners as well - they are already psychologically well suited to that contained environment. Assume that the submarines already have air scrubbing technology and are accustomed to weeks or months below surface.
] |
[Question]
[
I have an archaeologist who specializes in ancient ancient Northern European civilizations. Due to some handwavy mumbo jumbo, he is brought face to face with a supernatural being which still speaks fluent [Proto-Celtic](https://en.wikipedia.org/wiki/Proto-Celtic_language) and/or [Proto-Indo-European](https://en.wikipedia.org/wiki/Proto-Indo-European_language) exactly as they were spoken thousands of years ago. Would the archaeologist be able to communicate verbally with this being or would the drift in accents over such a time frame be so severe that he could only communicate through writing?
[Answer]
## First the bad news
1. Archaeologists are not historical linguists, and historical linguists are not archaeologists. It is not at all likely for an archaeologist to have more than an amateur level knowledge of Proto-Indo-European. Please note that Indo-Europenists are much very much rarer than archaeologists.
2. Neither Proto-Indo-European nor Proto-Celtic were written. (This is why archaeologists don't bother to learn Proto-Indo-European historical linguistics; it's not as if there is any hope of ever finding an inscription in Proto-Celtic or Proto-Indo-European.)
3. Nobody knows Proto-Celtic to any degree of accuracy.
* We have a good idea of its phonemic inventory and of the sound changes which separate it from Proto-Indo-European.
* We know some parts of its morphology.
* We know some of its vocabulary.But:
* We only know *some* parts of its morphology, and what we know is not 100% guaranteed to be correct.
* We only know *some* of its vocabulary, and for those words which we know we are far from certain that we know exactly what they mean.
* We have only a vague idea of its syntax.
4. Our knowledge of Proto-Indo-European is both a lot better and a bit worse than our knowledge of Proto-Celtic.
* We have a good idea of its phonemic inventory, but we are still struggling to formulate a complete theory of how those phonemes were actually pronounced.
Examples:
+ PIE had three series of dorsal stops, conventionally called palatovelars (written \*ḱ, \*ǵ, \*ǵʰ in our reconstructions), labiovelars (written \*kʷ, \*gʷ, \*gʷʰ in our reconstructions) and plain velars (written \*k, \*g, \*gʰ in our reconstructions). It *could* be the case that they were pronounced as their conventional names and notation would suggest; it *could* be the case that the proponents of the [glottalic theory](https://en.wikipedia.org/wiki/Glottalic_theory) are right and the actual pronunciation was quite different (involving ejective stops); or it *could* be the case that what we call palatovelars were pronounced as plain velars, and what we call plain velars were pronounced as uvular stops. We just don't know, and we don't really care all that much, because our reconstruction of PIE is intended more as a shorthand notation for the sound correspondence rules between the daughter languages.
+ PIE had three phonemes, conventionally called laryngeals and written \*h₁, \*h₂, \*h₃ in our reconstructions. We know that they could function both as consonants and as syllabic nuclei, and we know the effect they had on nearby sounds. But we have a very vague idea of how they were pronounced; the best guesses are [h], [χ] and [ɣ] or [ɣʷ] on one hand, and [ʔ], [ʕ] and [ʕʷ] on the other. We just don't know, and we don't really care all that much, because our reconstruction of PIE is intended more as a shorthand notation for the sound correspondence rules between the daughter languages.
* Our knowledge of PIE morphology may be significantly off. The basic problem is that it is quite likely the case that what we reconstruct for PIE morphology did never exist as a synchronic system, because our reconstruction may flatten long-term historical developments. (We reconstruct PIE by applying the comparative method to its daughter languages; those daughter languages separated from PIE over a timespan measured in millennia, and it's likely that the comparative method gives us a "compressed" view of PIE morphology.)
(To give a practical example, consider the English second person pronouns; looking at Modern English as a whole, we could say that English has three 2nd person pronouns: *thou* (singular), *ye* (plural) and *you* (singular and plural). But this synoptic view compresses centuries of evolution; such a system never existed as a common way of speaking.)
Some parts of PIE morphology, for example pronouns and demonstratives, are certainly poorly known, because the daughter languages are too divergent to allow us to make a solid reconstruction.
* We know a lot of PIE roots, and we know how to make PIE words out of them. The problem is that in many (maybe even in most) cases our knowledge of the *meaning* of those roots is foggy at best. For example, we know that there was a root [\*ǵʰelh₃-](https://en.wiktionary.org/wiki/Reconstruction:Proto-Indo-European/%C7%B5%CA%B0elh%E2%82%83-) in PIE; it was certainly a common word, because it has reflexes in all the Indo-European subfamilies; but we can only reconstruct its meaning as "yellow", or "green", or "to shine", or "to flourish", because its descendants include such disparate words as Latin *holus* (green vegetables) and *helvus* ("of the colour of honey"), Greek *khlōros* ("bright green") and *kholē* ("gall bladder"), English *yellow* and *gold*, and Russian *zhyoltyy* ("yellow") and *zoloto* ("gold").
(The good news is that for quite a few words we have rock-solid meanings; \*ph₂tḗr meant "father", \*méh₂tēr meant "mother", \*bʰréh₂tēr meant "brother", \*swésōr meant "sister" etc.)
* We have very little good understanding of PIE syntax. The simple truth is that the descendant languages are all over the place, and just about the only thing we can say is that PIE has almost free word order, like Greek or Latin. Other than that...
## And the good news
A historical linguist specializing in Proto-Indo-European (and there are not all that many of them, probably less than a hundred in all of Europe) would probably recognize the speech of the ancient being, and they would most likely begin to make sense of the being's utterances in a relatively short time, especially if the being is cooperative and engages in a bit of elicitation. (Show a rock, hopefully say pérwr̥; show his hand, hopefully say meh₂nos and so on.) The point is that we know the underlying system of PIE, and could probably fit a practical realization on our knowledge.
[Answer]
You have a more immediate question: why would you expect your archaeologist to even *know* Proto-Celtic or Proto-Indo-European? An archaeologist working with the Egyptians or the Sumerians or Old Norse or Ancient Greek or some other civilizations could be reasonably expected to know something of the language of the people they study because said people left written records as part of the archaeological record, so knowing the language is an added tool in their research.
That isn't the case the reconstructed languages; indeed, one of the reasons they're reconstructed in the first place is that there are no written records to use to figure them out. There's no benefit to a field researcher knowing that *mel-nés* (or something that sounds sorta like it) *probably* means "honey" in PIE since they'd never come across anything where knowing that was remotely important to their research, even if they uncovered an entire beekeeping industry from the time.
So unless the archaeologist also had a completely separate interest in linguistics, you need to explain that, even before you get to the problem of not being sure how it was really pronounced.
[Answer]
I agree with Alexander. There is a HUGE difference between understanding a written language and understanding the spoken version of that language.
Take Egyptian hieroglyphics. They are more than 3,000 years old. There are many people who can read them and have a general understanding of what is being described. However, there is no one on this planet that can accurately pronounce those words exactly as they were pronounced 3,000 years ago.
Because that language was not passed down exactly intact to anyone in modern times. And if someone claimed to know the ancient tongue, how could anyone possibly verify that?
To take a more modern example. The English language has evolved a lot over the last 500 years. It is unlikely that some one speaking only Old English would be able to communicate effectively with someone speaking Modern English.
And even in modern times. There are regions of the US where English speakers are partially or completely unintelligible to English speakers from other parts of the country. People from the South or the North East particularly have this issue.
When you add in regional slang and pronunciations, it is very unlikely that your hero would be able to speak to a monster that only speaks a 3,000 year old language.
[Answer]
**No.**
For this to work, your archaeologist will have to be handwaved along a good friend who is a philologist, and in specific, an **Indo-Europeanist** who subspecialised in western languages (Italo-Celtic, Helladic, maybe Germanic).
PIE is *thought to have* been spoken up until about 2500 B.C., which is 4500 years ago. You're only looking for a daughter language. It's a good guess where any specific group was at any specific time, so your archaeologist might end up in the middle of nowhere.
Further considerations: Of course, PIE and PrCelt were not written down, though your philologist, should you choose to bring one along, can. Also, and most importantly, both of these languages are ***reconstructions***. There are absolutely no written records of PIE, and Proto-Celtic is just tantalisingly out of reach of the earliest Celtic records. We do have some records of Gaulish and scraps of very early Irish.
By "reconstruction" we mean that modern, middle, and old languages are compared with one another --- their sounds, their words, their grammars, their syntax, and even some idioms --- and through this comparative method, ever older layers of language can be reconstructed. For example, we can see some kind of kinship between the words werewolf (Engl), vir (Latin), virá (Skt), fear (Irish), vyras (Lith.)
By looking at a whole mess of Germanic languages, we can deduce that the Primitive Germanic word was *probably* "weraz". We can look at all the other languages' data, and compare them with other similar words, and deduce that the Indo-European word was *probably* "wihrós".
It's almost a foregone conclusion that even the most proficient indoeuropeanist will not be able speak fluently with a native speaker of an ancient language. Unless that ancient language is Greek or Latin or Sanskrit, which we know well and what they sounded like. Anything older is educated guesswork.
[Answer]
Absolutely no. Not without extensive training.
Speech did not just happen. Humans did not just make up sounds, and form them into words. They used sounds they could already pronounce.
Babies babble phonemes of every known language, at birth. Over time, as they listen to their parents, they learn the important phonemes of the language of the parents, and stop babbling the phonemes that are not used in the language. Over time, they lose the ability to physically make the phonemes of languages they did not practice.
A case in point is the Chinese language. It uses almost no phonemes *in the same way as* [edit] spoken by any Western language. Thus, not only is it very difficult for Western speakers to learn how to speak it, it is very difficult for Westerners to even understand the subtleties of the phonemes from the language. It takes a great deal of training our auditory system to pick up the nuances in the language. There are many, many words in Chinese that sound exactly the same to us, but there are subtle (to us) but pronounced (to them) differences in inflection that make it a totally different sounding word to them. They would proclaim that the two words don't even sound close to the same. Likewise, when a native Chinese speaker learns English, there are some English phonemes that they find exceedingly difficult to pronounce properly. There is absolutely nothing like them in their language, and they have therefore never developed the ability to form them.
Any language that was spoken thousands of years ago, would have been made from a unique subset of the phonemes that babies would have babbled at the time. We have absolutely no idea what those phonemes were, or even what they might be. There are no guarantees our vocal system would even be able to make them.
There is also no guarantee our auditory system would even be able to decode them.
So this archaeologist is in for an awful lot of speech training and speech therapy in a second language from this alien linguist.
See for instance <https://files.eric.ed.gov/fulltext/EJ1152473.pdf>
or <http://englishspeaklikenative.com/resources/common-pronunciation-problems/chinese-pronunciation-problems/>
or <http://www.speech-language-development.com/phonemic-awareness.html>
or <https://psychology.iresearchnet.com/developmental-psychology/language-development/babbling/>
or <https://www.asha.org/Practice/multicultural/Phono/>
or <http://esl.fis.edu/grammar/langdiff/chinese.htm>
or
>
> As a mono-syllabic language, each character has only one syllable and
> cannot be analyzed at the phoneme level as English is. (hong xu, 2014)
>
>
>
<https://prezi.com/dlbylu4heego/mandarin-chinese-vs-english-phonemes/>
[Answer]
I haven't read all the answers in detail, but I think one aspect that isn't mentioned, is that proto-celtic or any other proto-language is an artifact that tries to sum up the traits that can plausibly explain the features as well as the differences we find in modern languages of a language-family. The actual, spoken languages at the time will almost certainly have been at least as diverse as what we observe today, at least if the speakers were spread out over any distances great enough to prevent frequent contact; just think about how dialects exist (and still evolve) in every moderne country, even with good communication media. The proto-languages, in my opinion, are in many ways what you would get if you tried to unify all modern, Indo-European languages into one, covering all variations in phonemes and grammar.
So, to answer you question: I don't think knowledge of a proto-language would be much actual use in practice.
[Answer]
It would potentially be very difficult. The written words of an extinct language would be preserved but how they are supposed to be used and pronounced in spoken language is mostly based on unspoken social contexts that a writer would assume any contemporary reader would know.
Take Latin for example. Despite being a nominally "dead" language for hundreds of years Latin was still used heavily in religious organizations and in the sciences. As a result, people still had a good handle on Latin rules of grammar and vocabulary. However, despite this the way they pronounced Latin looked nothing like how a Roman speaker would have pronounced it. A Latin speaker from 0 C.E. and 1900 C.E. would each sound like they were speaking complete gibberish to each other, despite speaking the same language. This is despite the fact that they could both potentially read a document written in Latin.
We only know this because of later efforts to reconstruct the pronunciation of Latin as to how it would be "originally" spoken (noting that Latin pronunciation probably evolved through the ages, as with any language), [and there was a huge effort towards moving towards the "original" pronunciation from the Neo-Latin one at the turn of the 20th century](https://en.wikipedia.org/wiki/Traditional_English_pronunciation_of_Latin). This was the crux of the "SIS-er-o versus KEE-kir-o" issue in *Goodbye, Mr. Chips*. Changes to Latin pronunciation are still going on even today as people continue to reconstruct how the language was pronounced back in the "old days".
And this is *with* potential context as to how to pronounce or translate certain words. With a language for which any potential context for pronunciation is long gone, as with Proto-Celtic or Proto-Indo-European, it would be a lot harder.
] |
[Question]
[
I'm writing a story where the superhuman heroes fight hundreds of thousands of zombies. The zombies are fast and agile and completely surround the heroes. Dead zombies pile up around them until the zombies are jumping down on top of them. The heroes realize they have to continuously climb the pile of dead zombies to maintain the high ground.
At the end of the battle (with the heroes victorious on the very top), how steep is the resulting pile?
The angle of repose for a specific material is the steepest slope which the material can be heaped without collapsing.
Here's a table from [Al-Hashemi and Al-Amoudi](https://www.sciencedirect.com/science/article/pii/S0032591018301153) with representative values for other materials:
[](https://i.stack.imgur.com/YJ3lH.jpg)
[Answer]
*1) A vaguely-argued upper bound.*
This turns out to be a surprisingly common problem for providing answers here, and I have yet to find a good value.
In [The logistics of corpse disposal](https://worldbuilding.stackexchange.com/questions/144052/the-logistics-of-corpse-disposal/144085#144085) I gave 45 degrees, arguing that "Most stuff is lower, I know nothing that's steeper, and steeper means fewer bodies, so 45 is likely our worst case.". I feel this is a decently defensible upper bound.
---
*2) A spherical-cow lower bound.*
While, as others have said, the exact value may be hard to calculate, we can also at least establish a lower bound, by establishing a precise value for the case of a zombie spherical cow, which we shall presume to be frictionless except against the ground, and incompressible.
This works out at 23.8° (via <https://eng.libretexts.org/Bookshelves/Materials_Science/TLP_Library_I/33%3A_Granular_Materials/33.4%3A_Angle_of_Repose>).
That's reasonable as a lower bound, though as Nosajimiki points out, kinetic effects of people walking on them may mess with that.
However, as I understand the angle of repose, it's the angle of stable rest. Than angle of dune sand where you can walk down a sand dune and NOT cause an avalanche of more than the sand you displace. It's the angle of the bodies where you can scramble over them and not cause their sliding about to amplify and cascade. So I'm unsure whether this would actually have a significant effect.
Every assumption we made (spherical, incompressible, frictionless), reduces the angle of repose, so we can reasonably round up and still call it a fair minimum angle.
That still leaves us with a range **between 25° and 45°**. We could split the difference and call it **35°**, perhaps, as a reasonable guess.
However... we don't need to guess.
**We can try a PRACTICAL EXPERIMENT!**
You didn't expect to find that in an answer, did you? And, OK, I'm lying. But I can at least *simulate* it.
Most computer games have decent friction, gravity, collision, and rag-doll physics, nowadays. So what's a game where I can create a gajillion corpses and let them just... pile up?
---
*3) UEBS II, 1,000 modern soldiers*
Ultimate Epic Battle Simulator II (UEBS II) might be able to handle this. I note that it has a checkbox for "volumetric blood" with the note "can drown units", so this is clearly expected to handle LARGE armies.
It lets me set 1 million regular zombies to attack a thousand modern soldiers. I placed the zombies in four groups of 250,000, to surround the soldiers... OK, the soldiers died fast.
---
*4) UEBS II, 1,000 super-soldiers holding their ground*
Let's make the soldiers be ubermensch, have ten times the firepower and ten times the health, as well as a 50% chance of blocking melee attacks.
After massacring 1,000,000 zombies, which took quite a while at about 300 zombies a second, I see that **the angle of repose in this game is 26°.** But I'm skeptical: in this game, this feels a deliberate effect, that they've engineered. They may have just picked a value that "looked right". On the other hand, it does look right.
Also, your suspicion was correct. I set the 1,000 supersoldiers to hold their position and fire, on the side of a gentle mound. Initially, it mattered: the zombies coming over the mound could only be fired at when they crested the rise, so they died much closer to the soldiers. On the other side, there was a significant distance that could be shot, so the zombies were kept well away.
But as the bodies built up, this stopped being an issue, as the bodies themselves made a mound, which advanced towards the soldiers as the zombies fell. Eventually, they were in the dip at the top of a pyramid, surrounded by mounds on all sides. The soldiers killed them all, but took heavy casualties, with little more than six hundred of their original number remaining.
[](https://i.stack.imgur.com/F3ufn.png)
*(26 degree angle of repose: this looks about right. If you placed a body on there, you wouldn't expect it to slide to the bottom, but you could imagine it doing so if you gave it a bit of a shove.)*
---
*5) UEBS II, 1,000 super-soldiers, moving tactically*
Setting the soldiers to attack instead of hold their position, they were able to scale the sides of the body-berms and shoot the zombies as they approached up the pile. This resulted in a differently shaped pyramid, with the berms becoming a ring around their original position, expanding outwards rather than constricting inwards as it had when they'd held position. This meant their lines eventually became too thin to hold back the flood, so they had to retreat once the zombies broke through, and defended just one side of the ring, making the top of their pyramid lopsided. As that side rose up, they eventually recaptured the lower side of the ring.
Rather than losing a third of their number, they lost only two out of a thousand men. This approach was clearly better, tactically.
---
*6) TABS, 1000 halflings vs 1 dragon*
Totally Accurate Battle Simulator (TABS) is on sale in Steam as I write, and is much cheaper than UEBS II anyway. It's for *much* smaller-scale battles, but with a fight on a slope, I was able to get some confidence in the the angle of repose from just 1,000 halflings, though that gave me a framerate around 3 fps.
**The angle of repose in this game is just 11°!** But watching the fall and slide into place, I am once again skeptical. I think it has them being VERY slippery. This would be the AoR of something like wet liver. Or perhaps the ground is slippery, and the slope they are on allows the ones at the bottom to slide sideways because of the sideways pressure from those on the ramp. Maybe testing on a ramp was a bad idea, but it was the only way I could find to make it work.
[](https://i.stack.imgur.com/65M2D.png)
*(11 degree angle of repose: this just looks too shallow. If you put a body at the top, it feels like you wouldn't be able to shove it so it slid to the bottom.)*
Overall, then, my idea of simulating it fell short, but did highlight some of the variables. I didn't expect friction to be such a big deal, for example.
In the end, you'll likely have to pick a number. UEBS' angle feels about right, viscerally (ahem), and I do feel anything much steeper would look weird and unstable.
I heartily recommend using a simulator like these (UEBS II in particular), to get a sense of what your battle would be like. I'm not affiliated with either of the games, but did buy them for this question (Yes, I spent $29 after tax on trying and failing to answer this question. Shut uuuup!), and it was eye-opening in various ways.
At 300 dead zombies a second, that results in *rivers* of bodies flowing down the outside of their corpse-pyramid. Everyone gets spattered in blood. Of course, it's simplified: the soldiers aren't harmed by their own bullets and have perfect target-acquisition skills, etc. And blood does drain out of bodies, so the "volumetric blood" option may be an eye opener, though I suspect it's considerably less than realistic.
Well worth setting up a simulation of it all, anyway.
[Answer]
## They will not pile up like you think
The best examples of what you are looking for will be from photographs of mass graves or pictures taken by over zealous hunters and fishermen (I don't recommend doing this research yourself). Based on this, I'd say that the angle of repose for a randomly stacked pile of bodies appears to be about 20-30 degrees. A greater angle can be achieved with careful stacking like you might find in certain holocaust pictures, but that does not apply here. Human bodies tend to splay out wide, but they also like to slide against each other, tumble over, etc. So, I'd expect a random pile of humanoid corpses to be closer to 20 degrees
... but this is not how a battlefield works. You have a whole army of zombies and heroes stomping around on these dead bodies, climbing them, kicking them out of the way, etc. This means that at any time the bodies stack more than 2 or 3 high, that the zombies trying to pass them will not just be walking over them like a solid hill top. They will be tripping over them, getting their feet stuck, falling when a body slides out from underneath them. Eventually the bodies may build up higher, but expect a very low hill gradient.
Also, dead bodies several deep can make terrain virtually impassable; so, unless your zombies are smart enough to clear their own dead, your heroes will slowly expand their kill radius as the zombie threat approaches more slowly further flattening the gradient of dead bodies.
This leads to a few very important conclusions:
1. Your heroes should NOT try to get the high ground. The higher you go, the less stable your footing will be. They want to keep the zombies tripping over their own dead while avoiding the bodies themselves.
2. The zombies will prevent the mound from getting very high. Instead of piling up, the zombies clambering over the dead will force the dead bodies backwards; so, instead of a giant mound, you'll just get an ever expanding field of bodies that is no more than a few bodies tall.
3. Unless the heroes are completely surrounded, they will back up as the bodies pile so that they can avoid having to stand on them.
4. This churning action of the bodies on the battle field means that some live zombies may get trampled into the dead ones. This will further destabilize any piles as they try to claw their way out and makes standing on a mound of "dead" zombies especially dangerous since a live one might in the chaos reach up through the dead ones to get you.
[](https://i.stack.imgur.com/SmxAM.png)
## Also, High Ground is not an advantage against zombies
First of, the high ground is a time honored advantage in many military traditions; so, unless your heroes have a lot of experience fighting zombies specifically, they may still seek the high-ground, only to realize thier disadvantages when they get there.
In the case of killing zombies, the low ground provides your heroes better LoS (Light of Sight) to be able to kill a maximum number of zombies. In a normal modern battlefield, infantry try to spread out to minimize how many soldiers can be shot down in a single burst; so, you never really need a deep firing line, but against zombies, the enemies are much more densely packed, and require aimed head-shots instead of sustained fire to take out. This means that you should ideally have a firing line several shooters thick.
The problem with the high-ground for modern firearms is that even if the person in front of you is crouching, you may or may not be able to see past them to shoot depending on the hill gradient, but if you have the low ground, everyone in your block can see and fire up on an enemy as they come over a ridgeline. This is important when fighting zombies specifically because you want a concentration of force using aimed shots fired at close range to maximize your number of head shots and minimize your amount of wasted bullets.
[](https://i.stack.imgur.com/9qy0A.png)
Melee is also at a disadvantage on the high-ground against zombies because all of the things that give a human army and advantage on a hilltop do not apply to a horde of zombies. Some of these advantages may apply to a natural hill top, but not to a mound of zombies.
* The improved field of view that normally makes it easier to spot and respond to ambushes and flanking maneuvers don't matter if you already know you are surrounded by an endless horde of zombies in every direction.
* Many hill tops have some passable and some impassable areas allowing you to funnel the enemy into a chokepoint or guard your flanks. Zombies likely won't pile steep enough for these to form.
* Charging up a hill is tiring and slows you down, but zombies (in most canons) do not tire and they do not charge making this a moot point.
* Low velocity weapons like bows and javelins suffer a major loss in effectiveness when launched uphill, but zombies don't have any ranged weapons to mitigate.
* Hills tend to be uneven terrain which breaks up organized battle formations. Since zombies have no shield walls or phalanxes to maintain, this is almost a moot point. The unevenness of corpses will trip them up here too, but even the low points will be a rough terrain of corpses in this case.
However, there are disadvantages to the high-ground that do apply to zombies:
* It leaves your lower body much harder to defend. It's harder to parry or block attacks that are coming up at you than from on-level or above.
* It shortens your reach compared to your opponent.
* Like with the gun problem, you cannot form a phalanx over a ridge line. Even though a spear wall may not kill zombies out right, it would be helpful for stopping the advance of the zombies so that your front line has more liberty to deliver the killing blows
[](https://i.stack.imgur.com/Uj63l.png)
[Answer]
You can consider sandbags as an approximation. Those are heavy soft bodies with cloth skins, similar to your clothed zombies. Now proper stacking lets you build a mound of sandbags nearly vertical, but there's guidelines for making stable mounds, which can withstand external forces pretty well. For example the [reference for dikes from the North Dakota State University](https://www.ndsu.edu/agriculture/extension/publications/sandbagging-flood-protection).
[](https://i.stack.imgur.com/vPYUr.png)
This article lists two different recommendations for stacking, one ending up with an angle of 45 degrees and another with 33 degrees. Since we're dealing with a dike design that needs to withstand an enormous force, I think the 45 degrees angle would be stable enough on its own. That's not necessarily the natural angle of repose for sandbags (or zombies) stacked randomly but I believe it wouldn't be too far off.
For another reference, consider finding imagery of stacked human corpses. There's grim WWII imagery that may suit your needs and let you estimate an angle of repose. I'm not going to look up those pictures myself because I value my night rest.
[Answer]
Unless the arms and legs fall of when the zombies die, I would imagine they could be stacked vertically as the arms and legs are lodged under other bodies preventing them from tumbling down.
Of course the given scenario where the hero has the high ground, the zombies would die before they reach the top and tumble back down the hill, eventually creating an ever expanding circle, where the hero keeps moving forward to be at the edge, and not let the zombies on top of the hill.
[Answer]
Dead zombies offer very bad foothold. If your heroes have the room, they would be better off, retreating slowly, so the zombies are slowed by the corpses, but the heroes have a clear floor to maneuver.
Of course, this is not possible, if they are surrounded. But they would still be better off, moving around and avoiding a pileup. You will always want to have stable footing, when fighting hordes of zombies.
If the zombies are forming a horde so dense, that maneuvering isn't possible, your heroes have a real problem, superhuman or not. because that also means, that the zombies can't just fall backwards after being killed. They would fall against other zombies. The following zombies would push the killed zombies against the heroes, crushing them without the heroes being able to kill the pushing zombies through the wall of pusehd dead ones.
But let's assume, they are already on a small hill of dead zombies (or just on lightly higher ground, like a literal hill). The newly killed zombies would fall down in front of the heroes, so the heroes would quickly be on lower ground. They would either have to constantly pull the killed zombies towards themselves, to stay on the high ground. They either do not have the time for that, since the next one is alread attacking, or they have enough room, the move themselves.
In short, in a relatively realistic scenario, the zombies wouldn't pile up at all (well, maybe 2-3 falling on each other, but not really).
If you want the pile of dead zombies anyway, you are relatively free to chose an angle yourself. It's fiction after all. Just look at some pictures of piles of sand sacks and imagine a zombie trying to climb them (the sand sacks, not the pictures). If you can imagine it, you have a good angle for the slope.
[Answer]
Obligatory 'Not an Engineer' - however, I think the angle could be very steep. Steeper than 45 degrees.
I have no means nor inclination to do the maths - but here's my reasons:
1: Human Skin has a high friction, Even with Headshots, there's unlikely to be enough blood to severely impede this, plus as Blood dries, it gets very sticky.
2: Mass of each body - this means that unlike sand which has high friction but low mass, you have high friction and high mass which leads to a lot of traction force between each zombie corpse.
3: Limbs. Arms and Legs can interlock in fun ways, although not as effective as if someone consciously stacked the bodies, the limbs can substantially increase the surface area and act like a mesh of sorts to further increase the angle of repose.
Finally, unlike most of the items where we have data for the angle of Repose... Humans aren't grains or particles.
] |
[Question]
[
**Closed**. This question is [opinion-based](/help/closed-questions). It is not currently accepting answers.
---
**Want to improve this question?** Update the question so it can be answered with facts and citations by [editing this post](/posts/71719/edit).
Closed 6 years ago.
[Improve this question](/posts/71719/edit)
Cultured meat, also called synthetic meat, cell-cultured meat, clean meat, etc. is a reality. It seems that the only limitation so far is the mass production of it. This might be accomplished in the next decade.
If cultured meat were cheaper and equally as good as real meat would that make animal slaughter illegal? As there would be no reasons to breed animals for human consumption is it wrong to assume that in a not so far future animal slaughter will be illegal?
[](https://i.stack.imgur.com/mo1M0.jpg)
[Answer]
We can't say what it would do, but we can say what it could do.
It most likely wouldn't become illegal, certainly not within the next decade. However, it could make real meat extremely unfashionable, sort of like how wearing real fur has become - which, AFAIK, isn't illegal in most places. This would result in meat disappearing from supermarkets, and butchers would become hard to find.
If that happened, real meat would become a specialty item and so you'd have to really go looking for it, probably only available in big cities or over the Internet.
There is one possible mitigating factor. Meat is a huge industry, making up a large proportion of many economies. There would be extremely strong pressure from the farming community (amongst others) and their representatives/lobbyists to ensure that consumption of meat continues.
**Edit**
Having said that, once it has become unfashionable, it's possible a hard talking anti-meat Donald Trump type character could become president and try to make it illegal.
**Re-Edit**
>
> *I can imagine by that time there will be a lot less resistance to*
> *stopping people slaughtering innocent animals than there is to*
> *stopping people escaping war-zones and economic disaster.*
>
>
>
What I mean by this is that while he faced stiff resistance to his immigration ban due to the potential human rights implications, someone looking to ban real meat in a world where artificial meat is cheaper, equally good and does not involve animal cruelty might not be opposed so much (other than by the real-meat industry, which will have shrunk considerably if eating it has become unfashionable)
[Answer]
# There will be a debate. And this is good plot fuel.
There will always a few ['enthusiasts' that will pay ridiculous amounts for their gastronomical jollies](http://www.therichest.com/luxury/most-expensive/20-most-expensive-foods-in-the-world-and-where-to-get-them/). And there will be [those that try to cater to that by squirming their way around regulations](https://en.wikipedia.org/wiki/Whaling_in_Japan). So we can assume as a fact that there will always be those that want their meat "au naturel".
But I predict there will be an **intense debate** about breeding animals for human sustenance once synthetic meat becomes commercially available on a large scale. The economics, the environmental impact and the ethics of it will be arguments that will be brought up. Breeding a meat animal is not cheap, synth meat may become a whole lot cheaper. The environmental impact of breeding animals for meat is significant. Depending on how far we have gotten with mitigating the climate crisis, farming animals may become a subject of environmental regulations. And the ethics of bringing a sentient being into this world for the sole purpose of killing it, butchering its body and using the parts for our own purposes will be called into sharp question if we do not actually **need** to do it any more. For now we can excuse ourselves with "We have no other choice, there is no replacement". But with synthetic meat, that excuse it out the window.
Will it actually **prohibit** animal slaughter? That is hard to tell. But considering how hard it has been to ban even practices that actually are harmful to us — like smoking and consuming alcohol — we can expect that the [grandfathering](https://en.wikipedia.org/wiki/Grandfather_clause) and "[prohibition does not work](https://en.wikipedia.org/wiki/Prohibition_in_the_United_States)" arguments will be used as well. And the facts that meat farming is a culture and a tradition, and also an industry on all scales, from small family farms to huge multinational corporations, are other arguments that will be brought in.
During the process we can most likely assume that that some jurisdictions will ban the butchering of animals, while others will not.
All in all I would say this is all very interesting plot fuel for an author, with plenty of exciting venues to explore.
[Answer]
No, it wouldn't.
It might make meat cheaper, but there's a ton of reasons why meat from a cow would be tastier, have better texture and overall be just "better" than synth-cow.
What I could see is an evolution meat production and cooking. Synth-cow is ok for most purposes, but cow-grown cow could be reserved for those who can pay for it. I can also see a rise in tax and prices for cow-grown cow to "encourage" the supposedly healthier synth-cow trend.
Also, bear in mind the cost to the economy of employment. How many farmers and associated trades would be wiped out by changing to vat-grown meat substitute?
Real meat will increase in price exponentially - it would become a luxury food.
But people **would** pay for real meat.
[Answer]
There's already plenty of groups all over the world that want to stop all animal breeding and slaughter. If you provided cheap, decent quality animal products (meat, milk, eggs, leather, ...) that most people would prefer them in daily use, those people would no longer care quite as much about *preventing* those groups from carrying on with their agenda. And we've already seen that tiny vocal groups *can* influence restrictive laws when most people simply don't care about the matter.
The economical reality is a lot more complicated than fashion trends, though. Would the synth-meat *really* be cheaper and more desirable? Where does it come from? If you can synthesise it from organic waste (refuse, grass, ...), it would be a great boon, since raising animals is a very inefficient process. If you need ingredients that are more problematic (oil, gas, nitrous oxides...), it might very well be that the real savings are rather small. In that case, people would probably tend to use both meats alternately, perhaps keeping "real meat" for "higher" meals, the same way leather is today preferred to fake-leather.
[Answer]
No. Feeding animals growth hormones and keeping them in mass-stables in bad conditions is *not* necessary for producing meat. It's just cheaper, the animals be damned.
Lab meat will either be cheaper to produce than real meat, in which case the market will take care of phasing out real meat. Or it won't, in which case it will keep off the market. Ethical considerations are unable to influence the market and legislation now in order to guarantee a certain quality of life for meat animals, so there is no reason to assume that the availabilty of lab meat would make a difference.
Either it will be cheaper to produce, in which case you won't be able to escape it, or it will be more expensive, in which case it will never make it on the market.
That's the way the patty crumbles.
[Answer]
## Animals Slaughter Will Remain Legal for a Very Long (100+ Years) Time
People would *talk* about eating only synth-meat, primarily vegan/vegitarian groups, but at the end of the day it seems very unlikely. I have laid out what I believe to be the top real reasons for this.
## The Labor Crisis
Any government that simply bans the old-fashioned production of meat would suddenly discover that everyone in the agriculture industry (and the farmers would stick by the ranchers on this one) is voting against them in the next election. Or, in non-democratic countries, demonstrating/revolting against them. You also can't simply make the argument that the ranchers could go work in artificial meat plants; laboratory/highly sterile work is not in the training set of most, nor would they be inclined. Raising livestock (on a farm, at least) is a way of life, not a job.
There is no path that allows *politicians* to ban farm-raised meat, at least in the next 100 years.
## The Price
At the end of the day, the primary concern for most consumers is cost. If the taste is the same, the cleanliness is superior, and the cost is lower then consumers will go for synth-meat. The person doing the shopping/cooking doesn't even have to tell the rest of their family that it is synth-meat; they won't know the difference anyway. That makes it very easy to substitute in as a way to save a few dollars towards something else.
However, at this point we have a LOT of cattle in the world... a STINK LOT OF CATTLE. If synth-meat were to ever start becoming price-competitive, the cattle industry could (and would) start a price-war and bankrupt the large synth-meat producers. They might not be able to keep it up everywhere, but in many parts of the world synth-meat would not be viable until it had already taken over somewhere else and was produced at such a large and cheap scale that it could overtake meat.
Realistically, this is **at least** a 50-year path on this vector alone. And I think 50 years is being very aggressive, and that's really just seeking parity.
## Marketing
OK, even if synth-meat costs the same as normal meat or a few cents less per pound, marketing departments are going to ramp into overdrive on both sides. The synth-meat side would be running constant advertisements showing young animals with big eyes all day long. And that would probably work very well on the upper and upper-middle classes. On the other side though, I think farmers would sweep the middle and lower classes, which comprise the majority of people. Some marketing advantages that farmers have include:
* Everyone already eats "normal" meat. They don't have to get people to switch sides, and it's much easier to maintain momentum than to gain it.
* People do not have a blind trust in technology; it's much the opposite. Look at fruits/vegetables as an example where the great majority of GMO products are perfectly safe but everyone still prefers non-GMO. They won't necessarily pay more for it, but they sure won't buy GMO products that cost more or if they are at the same cost.
* Farmers/ranchers have many established venues that attract large amounts of people everywhere in the world. From farmers markets to rodeos to county fairs and parades, they have a huge presence.
* Farmers/ranchers are willing to spend more time as activists than the marketing department of SynthCorp and all the vegan organizations put together, by a huge amount. There are simply orders of magnitudes more people who live as ranchers, and they are all willing to put in all their free time into fighting synth-meat (where the guy in marketing for synth-meat is willing to put in 9-5 and that's about it).
## Terrorism
At the end of things, if someone is trying to disenfranchise the meat producers of the world they will encounter forceful resistance. I suspect that a number of militant pro-synth groups would come out as well. The difference though is that all a farmer has to do is drop a few dead rats into the middle of a synth-meat production floor to force a full shutdown and decontamination of the factory (costing the company days of production), but it's hard to stop the normal meat trade without harming the animals.
In addition, once you start talking about adding poverty to an already poorer (comparably) group of people, you start making ANGRY poor people. And when you talk about people in agriculture, you are talking about disproportionately well-armed angry people. There will be fatalities, almost entirely on the synth-meat side.
[Answer]
If you have the technology to produce synthetic meat but not synthetic milk, you still have to find a way to deal with the 50% of new born animals which are never going to produce milk.
If it became illegal to kill them, presumably the cost of milk production would double, and you would still need to dispose of them somehow when they died of natural causes.
Some groups of humans would probably consider selective abortion as morally wrong as killing the animals after birth, so that solution might not be acceptable even if it was cost-effective.
The same problem would arise when using eggs for food, of course.
If humans still wished to keep carnivorous animals as pets, how would they be fed if there was a ban on intentionally killing animals? (Not to mention that producing pet food is one way to dispose of the milk and egg producing animals which don't provide high quality meat at the end of their working lives).
[Answer]
No, meat is not the only product of animal slaughter.
We also collect the hides, bones, fat, and pretty much everything else as an utility.
Plus, steak isn't the only eatable thing in a cow, bone marrow and guts are also eatable and ate.
[Answer]
Nope.
There's much more to meat than steaks, sausages and hamburguers, you know.
By the time we get synth-meat to substitute everything meat-related (and I'm not including leather and bones) coming from cows and pigs, a Star Trek's replicator would be something ordinary.
[Answer]
1. Hunting is critical in some ecologies at this point. Because humans have removed all the top predators in various places, it is only the hunting that culls prey species and keeps them healthy. So this kind of hunting would, in my opinion, continue.
2. Breeding for food is the only thing keeping several species from going extinct. If it is no longer profitable to keep a species alive, its ranges will be sold off for land. I can easily imagine ecology-minded folks campaigning heavily for "real meat" in order to preserve grazing lands.
Basically, artificial meat might decrease the slaughter for food, but it might result in a lot more animal deaths. Economics isn't in animals' favor, and this might make them even less relevant.
[Answer]
In Germany, **unnecessary** cruelty towards animals is illegal. Several legal precedents have established that breeding and slaughtering animals for food is **necessary** cruelty and hence legal.
Introduce unquestionably safe vat meat and this changes.
[Answer]
Even if it became widely available, not all countries would adapt to it and a lot of poorer/primitive countries would not be able to afford or obtain the technology.
It might become illegal in some places, but in general I'd say no.
[Answer]
Even if growing synth-mean will be possible, there is no reason to expect it to be **cheaper** to produce kilogram of synth-chicken than kilogram of real chicken (which need about 2 kg of insects, which can grow by eating food scraps and gardening trash).
So it might be feasible in say local space travel, where you do not have vast structures needed. But again in long-distance space travel, where you have whole ecosphere, adding facilities to grow insects and chicken would be trivial.
And this is before comparing taste of rotisserie chicken with your synth burger.
Evolution in few billions of years optimized many processes related to biological growth, and beating it will take comparable time.
[Answer]
## It would collapse the ecosystem
None seems to have brought up this point. Even if everyone on planet was agreeing that slaughter of animal should be illegal. What do you do with all the chickens, cows and pigs on this planet. Livestock makes up a huge part of the animal on this planet. Here is an illustration.
[](https://i.stack.imgur.com/VJTfw.png)
Livestock has been one of the cornerstones for human civilization for as long as it has existed. Removing that is a huge change to ecosystem and not something that can be done lightly or fast. It would probably take decades of research just to come up with a plan on how to do it (somewhat) safely. And then we are probably taking centuries to implement this.
[Answer]
## I sure hope not.
For better part of history, animal products were to precious to waste, thus cooking traditions have recipes for nearly all parts of animals.
It wasn't until recently that meat became plentiful and world became obsessed with meat, ignoring other body parts.
Obsession with meat, means that even today proper fatback (important cooking ingredient) is hard to come by, because pigs are bred and fed to maximise loin and leg meat at expense of other parts, especially fat subcutaneous tissue. In turn, people forget how to cook properly, and how to utilise other parts of animal, which only feeds the supply/demand feedback loop.
If cultured meat became the only one, this obsession and market forces would literally eliminate every other animal part from market. There would be no
* bones for soup (gelatin and collagen improve the taste considerably, yum)
* fatback to garnish and control fat content of dish
* lard
* tongues
* blood sausages (blood, entrails and buckwheat, just fry with onion yum)
* liver (liver and blood are excellent sources of iron. Who needs idiotic supplements if you can have fried liver?)
* tripe
* brain
and other I can't remember immediately. I admit, I focused mostly on pigs, but same would apply to all kind of meat animals, we use a lot more than just meat, I would say that sometimes those other parts are tastier than meat itself.
Also, I would like to point out that the way animals are raised influences the taste - it depends on what animals ate, how they were raised, how cramped or stressful the conditions were. I would expect cultured meat to be quite bland.
[Answer]
# Cultured meat is just one step...
## Animals bred for other products are also killed eventually; also slaughter is *out*: now it's called euthanasia
One important point still hasn't been considered at all: animals are also bred for products like dairy, wool, manure or labor, which doesn't really need for the animals to be killed, but in practice almost always results in them being slaughtered when they become unfit for their purpose or the material they provide. The problem arises as many heavily breeded species (like dairy cows) are often naturally unfit for longer life-cycles (e.g. incurable painful diseases), which ethically asks for premature killing of them. Now this killing already has a different quality than a slaughter for meat and can also be considered euthanasia, so let's check out the differences:
>
> "**Animal slaughter** is the killing of nonhuman animals"[1](https://en.wikipedia.org/wiki/Animal_slaughter)
>
>
>
... usually for food, but also when diseased or unfit for their purpose (see chick culling).
>
> "**Euthanasia** methods are designed to cause minimal pain and distress."[2](https://en.wikipedia.org/wiki/Animal_euthanasia)
>
>
>
But even here *"in some cases the procedure is the same"2* to slaughtering. Also note that respectful killing of animals used for research purposes is considered euthanasia if performed painlessly.
Euthanized animals have even been sent to commercial rendering, making the distiction from slaughter even foggier.
I imagine animal *slaughter* could be quite easily prohibited, by replacing it with euthanasia, though I believe this is independent of the use of cultured meat, as animals bred for meat could also (and sometimes already are) killed painlessly.
Considering the great numbers of animals bred primarily for meat, it would still be a significant progress to total animal killing illegalization if the use of natural meat would be limited (or even prohibited) in favour of cultured meat.
I doubt the prevalent use of cultured meat would lead to an illegalization of general animal killing including euthanasia without a replacement of the various other uses of animals.
[Answer]
# Probably not.
### Economically
First off, the meat industry is massive. The majority of the world consumes meat as part of their diet; the illegalizing slaughter of animals would slash a major industry. Then you have to consider the rising trend of anti-synthetic food lobbyists, who, from xenophobia, will tend to be against this new "synth-meat", paired with larger grocery companies who want the money of these lobbyists, and the farmers whose jobs are at stake.
### Ecologically
Second, this would also damage the ecology. Letting lose hundreds of livestock which are dependent on a human food source is not good; without the aid of people, they're likely to die in nature, not to mention that many people rely on animal-based fertilizer (though this industry is considerably smaller). And, as Frozendragon showed up above, livestock makes up a majority of animals; letting them all die would probably be a change for the worse.
### Politically
There's also no political reason (besides to appease animal rights activists). Two consecutive industries simply mean more revenue and thus more tax money; what government doesn't want tax money? Unless a leader whose personal beliefs exceed his economic views comes into power (or lobbyists take action), it's not very likely they will outlaw grown meat.
### Disadvantageously
There are also disadvantages with the synthetic meat itself. Currently, there's still no way to grow specialized cuts (wings, etc.) because synthetic meat is bland tissue. No bones, organ meats, leather, or feathers. Considering how farmed animals have a lot of purposes other than meat, there's not really an advantage to switching to this method.
[Answer]
# No
You seem to assume that once an animal no longer has mass economic value, killing it could become illegal.
If we exclude endangered and protected species, we find that it is typically possible to kill anything that you own, provided that you do so humanely and not in an unusual way that would attract attention (ex. Public execution style).
For example, it is perfectly possible to have your pet put down by the local vet, even if there is nothing wrong with them. They are unlikely to be eaten.
Furthermore, synthetic meat is mostly suitable for mince meat. But even if it became the perfect replica of all meats currently consumed (And possibly a few 'designer' made up meats of animals that never lived or have gone extinct. Who wouldn't want to taste dinosaur?), many people would still prefer the real thing. And we still need leather for shoes and bags and car seats and many other things. Synthetic leather is really rather terrible.
**In Summary**
* We need all the products we get from slaughtering animals.
* Even if we didn't, we would want all the products we get from slaughtering animals.
* Even if we didn't, we could still slaughter animals. It wouldn't happen on the current scale, but we could. Unless the cow became an endangered species. Which is, if nothing else, an amusing concept.
[Answer]
No, not without a lot of other replacements.
Assuming, that synth-meat is awesome and tastes the same, there are a ton of other products, that animals are used in that are not meat related.
Leather for example.
Fats are another example.
Plus you have the fact that people would be scare of synth-meat. I know it would be a really ling time before I would eat it. Look at the results of the "corn products" on calorie density if current food products. Were just now seeing that play out an it's been about 50 years.
Corn products are actually a good analogy. A surprising amount of food (including tru-meat) are made with corn because it's cheaper (at least in the US). There have been some serious side effects, and some "hard to define" side effects.
Sugar isn't illegal, but we sure have plenty of synth-sugar. (as an example)
[Answer]
**Potentially, yes**
Something like this has already happened in fact. Less than 100 years ago most people on the planet would have considered outlawing hemp absurd since it was used *extensively* in industry. Despite that, through manipulation of the public and political corruption, vested interests achieved that ban and became global chemical superpowers.
People forget how easy it has become for powerful lobbies to control laws without regard for public interest. All it would take is a "synth-friendly" government whose members stood to gain personally.
[Answer]
A technical development can't change the law. The development of cultured meat might lead to pressure for a change in the law, but could not itself make real meat illegal.
[Answer]
I personally would not want fake meat, even if it is "just as tastey". Take a look at the meat industry currently.... we have animals eating a wide variety of grains and foods that simply do not belong to their natural eating habits for the sake of "taste" or being "plump". Have meat in another country with less regulations like say Mexico. The meat tastes 1000 times better and it isn't because of the cooking. I have bought raw meat there and cooked it up as I would at home.
All these additives to their food source along with our regulation putting in various preservatives and chemicals really makes me wonder if doing something that is completely cultured from chemicals/genetics is really the way to even go. For example.... many super markets place red dye in the meats to make it more appealing to primal instincts. Feeding Cow and fish things like corn for example, is adding carbs and starch to foods that should have very little of either and have thrown off our diet balance in the name of having fattened animals.
I would rather see better regulations on what they feed the animals and how they are bred than to see us completely neglect real meat. In the end, humans are the top of the food chain. In some ways self-inserted due to our ability to make weapons so we can kill things stronger than us, but still we are at the top and have caused many species like wolves to become almost non-existent. Of course this is all speculation, but I would imagine a drastic reduction to the meat industry would cause an over population of some animals as many areas allow for deer hunting during certain times of the year to help population control.
To conclude though, I would not be opposed to synthetic meat as long as people who choose to have real meat are still able to without scrutiny. It would be like yelling at a vampire for having real blood when there is a new synthetic substance out.
] |
[Question]
[
Ever since Tolkien most, if not all, works of fiction including orcs portray them with tusks. Though this achieves the effect of portraying them as animalistic, what would the real world applications of this feature be? Would it cause any health problems or change their dietary preferences?
[Answer]
## It Reflects Dietary Differences and Requires Surprisingly Little Hand-Waving
The answer is going to depend on whether the tusks grow up out of the lower jaw, down out of the upper jaw, or in some other direction. Each will have starkly different uses, benefits, and detracting aspects. For the sake of brevity and because they are the most common depictions, I will only consider tusks that grow from the lower jaw up, as in this fellow:
[](https://i.stack.imgur.com/VCmPA.jpg)
The short story of this post is that it's probably not better or worse, just different. Well, maybe a bit worse, but it's not a show-stopper.
**Evolutionary Issue**
Here's the big issue with small tusks that grow upwards - they aren't terribly useful for a tool-using species.
They can absolutely be used to help tear meat from a carcass that has already been felled, but you would have to really shove your face right in there to do it. For a species that has tool-use capability (they probably used tools to bring down the prey, actually), it doesn't make sense that they would then shove their faces in to strip the meat off.
There are other animals that have tusks that grow upwards - boars and hippos come to mind - but they largely use that set for face-on-face aggression. Given the comparably small size of typical orc tusks and the fact that they can use fists and weapons, the need for face-on-face aggression is minimal at best, and most likely non-existent.
These issues can probably be hand-waved by suggesting that previously the physiology of orcs suggested that they did participate in face-on-face fighting, back before they were walking fully upright and using tools. Back then their tusks were larger, and have been shrinking over thousands of years. They could be used more for decoration and intimidation (as in the picture above) than for other purposes.
**Dental Structure and Resulting Diet**
I'm sure dentists all over the world cringe at Orcs, and not because of their brutish behavior and strength. They are so often depicted as having tusks that are next to human-looking teeth, and that's just ridiculous. Human-like teeth are prone to crowding problems, which create alignment issues, which jacks with the whole musculature of your face - and that's without trying to make room for the growth of very large teeth.
What you would actually end up with is something more akin to the sabertooth tiger (albeit upside-down), where there is actually a good gap near the tusks and on the opposite side of the jaw:
[](https://i.stack.imgur.com/TWsWS.gif)
This is going to create a situation where, like the sabertooth tiger, the Orc is necessarily largely (if not entirely) carnivorous. Unlike in a hippo or warthog, I would guess that the jaw structure leaves too little space for grinding teeth for plant matter to be a substantial part of the diet. That does jive with many descriptions of Orcs though, and there are many instances of carnivorous animals out there that demonstrate it is a successful survival strategy (though I am not convinced it could give rise to a sentient, social species).
**Health Impact**
Jaw-attached tusks have many of the same problems as teeth, though to greater and lesser degrees. For example, while cavities (or cavity-like issues) are still a problem, it would be less a problem for orcs than for people. This is because cavities are often caused by a buildup of acid between teeth, but tusks require the existence of space between the tusk and other teeth, which reduces the occurrence and impact.
Issues that would be higher though include the fact that, being larger and external to the face, they would be more likely to be knocked/impacted and chip/break.
They would also force the owners mouth open somewhat, which introduces a vector for pathogens. However, it is likely that orcs have other adaptations to assist with that issue, particularly because they are also likely carnivorous and used to eating raw meat.
**Musculature Impact**
This is probably the area where most depictions get things wrong. Usually we see orcs as humans with some big teeth, but it doesn't just work that way. To support the added weight and distribution, the entire complex of muscles that works the jaw would need to be re-worked, which would impact neck, shoulder, and back musculature as well. The most noticeable difference would probably be that their face would tend to bulge more where the jaw attaches. It would probably move them closer to the [uncanny valley](https://en.wikipedia.org/wiki/Uncanny_valley) and make them even more repulsive to humans.
[Answer]
While there might have been a strictly practical use for these teeth earlier in their evolution--look to @GrinningX's answer for that, it had to have been selected for long after they have a use for it.
After all, if they have hands and tools, they would not need them very much.
I am going to draw a parallel between orc tusks and human breasts here.
Humans are strange when it comes to mammary glands. Bigger breasted women have been selected for, and thus, most ladies have mounds in that area. They've been selected as [a positive sexual characteristic](https://www.theguardian.com/science/2010/may/14/breast-size-evolution). But honestly, in the form they come, they are certainly not practical. While mammals and primates have boobs, they certainly aren't at all like human breasts. So...why? They don't make running very easy, and the larger size doesn't make for more efficient sources of milk for young.
The answer is as far as we can guess, is that collectively, males of the species found this more attractive, so we selected for breasts. More bosoms equaled more of a chance to reproduce, and was seen as an indicator of fitness and attractiveness.
So your tusks can be the same kind of thing. If you want them more prominent on males, tie it to testosterone levels--making it like deer antlers (while they fight with them, they are also for display). Females have antlers, but not as prominently as males.
**Health Problems/Differences**
So orcs aren't always that smart in fantasy lit. And there may actually be a little bit a of a biological reason for that. Jaw strength.
See, in humans, we were able to develop a bigger brain later in our development because we lost muscle strength, in particular, in the jaw. There's a [theory that a genetic mutation which governs jaw strength, which weakened in proto-humans, was a trade off for better intelligence](http://www.nature.com/news/2004/040322/full/news040322-9.html). It's more complex than that, actually (see the quote below), but there might be at least a little bit of a trade-off--stronger, and more muscular equals less brain power for the species over-all.
>
> our jaw muscles need to exert considerably less force from to produce it.
> This explains some peculiar characteristics of our skulls. Our teeth are as tough as those of other primates because they still need to withstand the relatively high forces exerted by our bite. But the rest of our skull can afford to be comparatively flimsier. The jaw muscles attach to the skull and inflict stress upon it when they work. But our jaw muscles can produce a strong bite through less effort than those of other primates. As such, they inflict fewer stresses upon the skull, which can afford to abandon some of its sturdiness. [SOURCE](http://blogs.discovermagazine.com/notrocketscience/2010/06/22/who-are-you-calling-weak-human-jaws-are-surprisingly-strong-and-efficient/#.WbS4M7LytD8)
>
>
>
As for medical problems, may I invite you to [Tusk/Dental Care for Pigs](http://www.minipiginfo.com/mini-pig-dental-and-tusk-care.html)!
I know you are thrilled beyond measure by this introduction.
>
> At about 5 to 7 months of age, the permanent canine teeth will erupt. These canine teeth grow continuously throughout the pig's life. They should be first trimmed at about 1 year of age and then trimmed on an annual basis. Without trimming, the canine teeth will become elongated and cause discomfort and a misaligned bite.
>
>
>
You could have teeth and/or tusks work this way, so they actually have to file them and maintain them regularly.
**Dietary Preferences**
Could be anything really. Take a look at this list of [tusked animals](http://animals.mom.me/mammals-tusks-4061.html). You've got walruses, elephants, hippos, pigs--notice that some of these are actually... ::gasp:: vegetarians.
Here's what the wild boar eats:
>
> The Wild Boar is an omnivorous animal that primarily feeds on plants.
> Plant matter comprises around 90% of the Wild Boar's diet as they feed
> on young leaves, berries, grasses and fruits, and unearth roots and
> bulbs from the ground with their hard snouts. Living in highly
> seasonal regions, Wild Boars have had to adapt to the changing fruits
> and flowers, and are known to favour the protein-rich nuts (such as
> acorns) that become available in the autumn and prepare them for the
> winter ahead. They will however, eat almost anything that will fit
> into their mouths, and supplement their diet by eating eggs, Mice,
> Lizards, Worms and even Snakes. Wild Boar will also happily finish off
> the abandoned kill of another animal. [SOURCE](https://a-z-animals.com/animals/wild-boar/)
>
>
>
Mostly plants, but pretty much anything they can get their hands on.
I'd say that orcs are more likely to be equal opportunity eaters. That is, omnivorous, so they can eat anything. It would be kind of fun to make most of them vegetarians.
[Answer]
Tusks are terribly effective weapons when fighting close range. Look at wild boars: they use their tusks while charging the enemy
>
> boar typically attacks by charging and pointing its tusks towards the intended victim, with most injuries occurring on the thigh region. Once the initial attack is over, the boar steps back, takes position and attacks again if the victim is still moving, only ending once the victim is completely incapacitated
>
>
>
If they hit it's not going to be funny.
[Answer]
Re "Ever since Tolkien...", were there orcs - using that name, not just orc-like creatures - in literature prior to Tolkien?
Now perhaps my memory is failing, but I don't recall Tolkien describing orcs as having tusks. Fangs, perhaps, such as apes have - which pretty much answers both facets of the question, doesn't it? Orcs have fangs (and their other qualities) because they are rather ape-like. And we can get an idea of their diet & behaviour by looking at what real-world apes do with their fangs.
[Answer]
Their application may be for display.
Bigger tusks could reflect a more fit individual and give them an advantage in attracting a mate (do orcs mate, I know in the Tolkien world all sentient species were created so the biology is beyond me)
They could also be able to be a display of social dominance (we don't have to fight because you are so much more tusky than me and I know I will lose).
As for problems, all sorts of heath problems could be caused by having a massive lower jaw to support tusks or difficulty eating, or real problems of an ingrown tusk pointing the wrong way.
[Answer]
AFAIK that's a remnant because they evolved from boars instead of apes, also the shape of their nose match.
"Modern" usage of the feature is (probably) to dig into your chest to eat your heart (*NOTE:* real boar tusks are used to dig into the ground to unearth edible roots and insects, beside males fighting in the mating season).
[Answer]
It could be an "accident" of evolution. Primitive, pre-tool orcs used in the same way that boars do: they possibly had powerful jaws that could open wide and used them as the primary weapon.
They might have become genetically linked (if such a thing is possible!) with the general health of the orc, and as such they become a symbol of sexual attractiveness.
Most importantly, they must never have become a hindrance to the orc's survival.
Then, by the time they learned to use tools and weapons, they were well established and they never lost them.
[Answer]
From Wikipedia:
<https://en.wikipedia.org/wiki/Orc>
"In The Silmarillion, Tolkien conceived the Orcs to be Elves who had been enslaved and tortured by Morgoth and broken and twisted into his evil soldiers. In other versions of their origin, including those from Tolkien's notes, the Orcs are depicted as the parodies or false-creations of Morgoth, animated solely by his evil will or perhaps, by his own diffused essence, and made intentionally to mock or spite Eru Ilúvatar's creations—the Eldar and Edain."
Like other posters have said, orcs had fangs. There was no evolutionary or practical reason for them to have fangs, much less big tusks. Their bodies were they way they were because Morgoth hated the other Valar (gods) and he deliberately made the orcs evil and horrible in body and mind to mock the creation of Elves and Men.
I remember from The Silmarillion that Morgoth was angry that other gods created children but the supreme god put a stop to it before Morgoth could create a race of children, which is why he twisted Men and Elves. I think he also created the dragons, trolls, balrogs, and most of the other evil creatures. Shelob the Spider was a notable exception, being a daughter of Ungoliant, a primordial spider demon.
Morgoth was a god, and he had godlike powers strong enough to corrupt spirits, raise mountains and warp life. Sauron was one of Morgoth's original corrupted spirits, which shows you how powerful Morgoth was.
Dungeons & Dragons (1977) depicted orcs as pig-like creatures with tusks on their lower jaws. Tolkien orcs were never like that.
[](https://i.stack.imgur.com/clnAR.jpg)
If the orcs you're thinking of are natural creatures, they might have tusks left over from an earlier stage of evolution. Perhaps they evolved from baboons, who have very dangerous fangs.
Like another poster mentioned, tusks on the lower jaw could be for digging or even ripping up tree bark to get at insects beneath. Once prey was dead, an orc could use his tusks to rip open the carcass to get at the raw meat. I don't think they'd be that good for attacking because they'd depend on the strength of his jaw muscles alone instead of being driven by the strength of his neck, shoulders and core like immobile upper jaw fangs.
For health problems, big tusks would interfere with an orc's ability to fully close his lips. He would get tooth damage from dry mouth, probably have a problem with saliva irritating his lips and chin, and slurring his words. Breaking a tusk could be very painful, and if an orc got an infection he might even die from it. Since the tusks are right in front of his face, there would be a good chance of them getting hit in battle. He might be self-conscious about his tusks and worry that people think that he's just a dumb animal-like barbarian.
] |
[Question]
[
I'm working on a map of several star systems (with the stars, planets, etc. not to scale with the map), and I'd like to show that they don't all lie in the same plane. Some orbits are perpendicular to the plane of the viewer, while others are flat, and still others are at odd angles.
In short, I'd like to show three dimensions of celestial motions on a two dimensional map, without trying to simulate three dimensions by showing the entire setup from some angle. This needs to be viewed only from the top down.
How can I do this?
[Answer]
[This answer has been invalidated by a clarification of the question, but is included here for reference purposes.]
Use height lines.
To indicate if the item is above or below the galactic plane (or other reference plane), you might use different line styles (as below with dotted vs solid lines)...
...or you could use lines that radiate from a center point.
I've also seen height-lines that emanate from a dash(or common symbol) on the center plane leading to the star/galaxy in question, but I cannot find a graphic for this at the moment. It may be enough that there's a star at one end of the line, and none at the other end, as long as the lines don't overlap other lines leading to other stars (which could be confusing!)
[Answer]
**Apply a z-axis number to each star/planet/asteroid etc.**
This works because maps (typically) represent stationary (or mostly stationary) objects. Even though the stars move and things orbit, those are predictable paths that we can represent using various ellipses.
For example, imagine the average world map we have. Mountains just look like big circles. Now imagine a bunch of dots on in space, representing stars, planets, etc. Each one of those also has a number beside it, negative and positive numbers included. A "0" represents the very center of your dimension. Higher numbers represent "closer" to the top of the dimension (closer to the top of the imaginary box), and negative numbers represent the lower regions (bottom of the box).
if your map includes the orbits of these stars and planets, you may want to draw a dotted line along those orbits, and place more z-dots along those orbits to show the different angles of orbit.
[Answer]
## Do it digitally.
A screen is still 2-dimensional, no? However, a screen allows you to add functions such as rotating the map - a tried-and-tested method of showing 3D. See Google Earth for an example:
You can also combine this with the other answers here to come up with a method of showing position, movement, and giving a visual cue to it all.
[Answer]
**With colors.**
I would use solar system representations like these:
That have orbital vectors demonstrating the orientation of the orbital plane like this:
For the 3D relationship you can use color depth mapping. Systems in plane are white, above plane shift to deeper blue, and below plane shift to deeper red.
[Answer]
**Use two maps.**
I was thinking about how space wargames (board, not computer) represented 3D. I recall at least one used two boards. One was horizontal and the other vertical, like a Battleship board. However, they represented the same thing. Each ship was represented by two markers, one on each board. This avoided needing to suspend playing pieces above the board. The location of a ship was above its counter on the horizontal board and in front of its counter on the vertical board.
If you really want to avoid an isometric view, two maps (XY and XZ, or whatever you prefer to designate them) would work. I think this would be clearer for star positions than planetary orbits, though.
[Answer]
A data visualization project I once saw had an interesting twist. While the developer had a database with a 3D model of the relationships of various objects to each other, he was trying to display this on a 2D computer screen.
His solution was to envision the data as something like a model illuminated from behind, with the computer screen being a piece of paper between you and the model. The relationships would then be something like shadows projected on the screen, with objects "closer" to the observer being clearly defined, while objects "farther" from the observer would be much fainter or fuzzier.
Being a computer model, this also had the advantage that the model could be rotated in the "space", so relationships changed depending on where the observer was observing from. If you hold the model steady, but envision the observer moving with the paper "map" between him and the model (with the constant light source always in a straight line between the paper and the model, the relationships now represent the observer's movement through space. For you, a series of maps could represent snapshots of the voyager through space. In a story, you could have the map made of "smart" paper and being a display connected to a database of the mapped star systems.
[Answer]
First, declare a baseline. You'd probably use Earth's orbital plane, or the galactic orbital plane depending on the scale of empire you're working in.
Now include three numbers next to each star chart (one per system):
1. Number of light years off of base. Depending on scales you would change your notation.
2. Number of degrees of "tilt" off of base.
3. Rotation of the tilt when compared to some arbitrary direction (center of the galaxy)?
So you might end up with a numbering like:
94\*36\*87
Which tells you that the system is 94 light years above the plane, is tilted 36 degrees off, and that the tilt is such that the "lowest" point of the orbits is 87 degrees off of the center of the galaxy.
[Answer]
So, Aify covered the most common analogy in the real world, the topographical map. The only other commonly used solution to this that I can think of is to use colors to represent altitude in a color-map.
Violet represents the low point of the map, and red the high point, and all distances in between are assigned a color value based on the percentage of difference. Anyone who has ever seen a rainbow already knows how to interpret this map. Some maps will use white as the high point, but let's not discuss those.
This is particularly effective in showing 3 dimensional motion as the human eye is quick to pick up on the color change of a moving object.
[Answer]
You could produce **multiple maps** viewing the scene from different angles, like so:
Alternatively you could make the map **anaglyphic**:
Or make it **holographic**:
[Answer]
Googling the [orbit of Pluto](https://www.google.com/search?q=orbit%20of%20pluto&espv=2&biw=1306&bih=898&source=lnms&tbm=isch&sa=X&ei=pPd1Vc31DsOwsATvxYBg&ved=0CAYQ_AUoAQ) and doing an image search should give you quite a few good options.
This picture in particular pretty clearly illustrates that Pluto's orbit isn't inline with the rest of the planets... It could certainly be extended to multiple star systems.
[Answer]
This map is an animated .GIF designed to bring out the third dimension for the [Galaxy on Fire Wiki](http://galaxyonfire.wikia.com/wiki/File:GOF2Map3D.gif).
[](https://i.stack.imgur.com/ev0tJ.gif)
By rotating the point of view slightly, it provides the visual cues to get depth out of a flat picture without the need for 3-D glasses.
] |
[Question]
[
The quote has many forms, but is basically "mathematics is a universal language." My question is if this is true? If we met aliens could we use mathematics to talk to them?
The fact that we could show them we know what 10 is doesn't seem like much of help in saying "do you come in peace?"
[Answer]
The use of prime numbers in communication is talked about in [*Prime Numbers and the Search for Extraterrestrial Intelligence*](https://math.dartmouth.edu/~carlp/PDF/extraterrestrial.pdf). Here's one method:
1. Create a rectangle.
2. Divide it into units, such that each side has the length of a certain prime number.
3. Encode images into the rectangular grid by making each square black or white (or a dot or a dash).
4. Take apart the image row-by-row or column-by-column and make it into one long pattern.
5. Transmit the message.
[The Arecibo message](https://en.wikipedia.org/wiki/Arecibo_message) used this technique (in a 23 by 73 grid). This ensures that a civilization must be relatively advanced to factor the multiple of the two numbers (which is 1,679).
You can transmit plenty of information like this, using only basic algebra!
Here's the message, gridded and colored:
[](https://upload.wikimedia.org/wikipedia/commons/5/55/Arecibo_message.svg)
Also, the consensus in [A World Without Mathematics](https://worldbuilding.stackexchange.com/q/2966/29) is that advanced technology is near impossible without mathematics. If they contacted us - or we simultaneously met - chances are good that they would have access to mathematics.
A more detailed way to communicate (used once) is to use a language like [Lincos](https://en.wikipedia.org/wiki/Lincos_(artificial_language)). Lincos is not entirely based in mathematics - in fact, much of it is not - but it uses mathematics in the "dictionary" that is supposed to be broadcast that explains the use of the language. Using Lincos, complicated conversations are possible.
[Answer]
**No,** mathematics is not a universal language. It is, however, the study of universal truths.
As long as both parties have studied the same truths, differences in language can quickly be figured out by both sides. For instance if we met a race of aliens that use the octal number system we could very quickly figure it out and share discoveries with each other.
But mathematics is infinitely big; we've only explored *some* universal truths. How do we know aliens would be attracted to the same areas of mathematics? Well, we use mathematics for reasoning about the world around us, so beings from other planets will almost certainly have discovered a lot of what we have, by studying objects, movement, heat, and time. But beings that inhabit quite different environments may have studied mathematics quite different to ours. For instance, energy-beings that exist outside time (or in 2-dimensional time?) or intelligent microbes that can teleport using quantum tunnelling. It is hard to imagine technologically advanced beings that don't know how to *count*, but beings that exist outside of space and time, where it doesn't make sense to ask "how many things are within <blah>", may have had no reason to study counting!
As to whether we could communicate about practical matters ("we come in peace"), the language(s) of mathematics are not designed for this sort of thing. *However,* the language of mathematical logic would be a good starting point: thing A has property B; provided C and D are true then E is true; for every F there must be at least one G. We could ensure that the aliens have the same understanding of these terms to us by applying them to mathematical examples. Then we could apply the same terms to real-world entities, and the properties they may have (e.g. "We" have the property "wanting-spaceships").
If the aliens are reasonably similar to us (social species with physical form) then it will probably be easier to just learn each other's language through immersion, like we do when we meet an unfamiliar human culture. But if the aliens do not really have a language and thus are poorly adapted to learning languages (e.g. they communicate using hive mind or telepathy, or we meet one individual from an asocial species) then mathematics could be a good way to establish a frame of reference. If they are not good at language but they are good at reasoning about the world around them, they will realise how our mathematical terms correspond to elements of their reasoning system. Adding in a few important concepts ("I", "you", "good", "bad", "hour", ...) allows some basic practical statements to be made about the real world. This is essentially the approach taken by [Lincos](http://en.wikipedia.org/wiki/Lincos_(artificial_language)), however Lincos is designed for broadcasting messages that may take millennia to reach their destination. If we actually *met* aliens it would be much easier to "explain by showing", even if their senses are considerably different to ours.
Do we have any guarantee it will work? No, but if it *does* work, it will be clear, because they will be able to respond to us with valid mathematical statements. Their understanding of our terms will either be correct and very precise, or obviously incorrect. And once they grasp the basics, expanding with more concepts will become much easier. So it is definitely a worthwhile approach to try.
**tl;dr**
* Mathematics can't be used to say "we come in peace"
* Mathematics *can* be used to establish common ground with *most* conceivable intellectually mature beings
* Although there is no guarantee they will "get" it, it will be obvious if they do
[Answer]
Maybe.
Our sample size of aliens to make such a claim is 0, so all we can do is give it our best guess.
The advantage mathematics has is that *most* of its content is fully defined within the system of mathematics. The number of axioms at the bottom of the chain is very small, and we have trouble comprehending an alien culture without them. Because most of the content is defined within the system, we can easily send a great number of statements to the aliens which can be cross-checked to develop a mutual understanding. It is harder to do that with natural language because the words often have more subtle meanings.
For example, arithmetic is defined within what are known as the [Peano axioms](https://en.wikipedia.org/wiki/Peano_axioms). The first defines a constant to start from. The next four define properties of 'equality,' and the final one defines a 'successor' function used to define the rest of numbers:
1. `0` is a natural number
2. (reflexive) `x = x`
3. (symmetric) if `x = y` then `y = x`
4. (transitive) if `x = y` and `y = z` then `x = z`
5. (closure) if b is a natural number and `a = b` then a is a natural number
6. There exists a "successor function" `S(n)`, such that if `n` is a natural number, `S(n)` is a natural number
The successor function is pretty simple, when viewed as a table:
```
S(0) = 1
S(1) = 2
S(2) = 3
...
```
That's it. Everything else in arithmetic (addition, subtraction, multiplication, etc.) is defined from those axioms. We consider those to be pretty darn hard to avoid, so it seems reasonable that any space-faring race will have a mathematics that is at least congruent to ours.
There could be issues if they approach math from a different direction, especially in the higher levels of mathematics (a sound wave graphed against time looks *really* different from its Fourier transform), but in theory we could use agreement in the lower levels to develop agreement in the upper levels.
Now we do know that mathematics is not universal. The Pirahã people have a [language](https://en.wikipedia.org/wiki/Pirah%C3%A3_language) which lacks recursion, as best as we understand it. Those Peano axioms depend heavily on recursion to do their work. It is yet unknown whether the Pirahã actually have a system of numbers or not. The language barrier is great enough that it's a real challenge to make heads or tails of it. However, the assumption is that it will be impossible to become a space faring civilization without developing something sufficiently similar to math that we can adapt our notation to meet theirs.
[Answer]
The problem isn't the math itself, it's the context.
We can throw all the math we know at the aliens, but it's going to be hard to find a version of it that sticks. For instance, the aliens might be blind; there goes any equations on paper, computer screens, or calculators. They'll most certainly have a different set of symbols used to describe their mathematical concepts, so we'll have to translate those somehow. I personally cannot think of a way to define any symbol in mathematics without defining another symbol first. It may help if both sides are actively working on the problem, but if we're just transmitting some theorems to the nearest flying saucer, they may think we're sending them a greeting, or a declaration of war, or the Hitchhiker's Guide to the Galaxy entry for Earth. Keep in mind that even though the idea has been presented that mathematics is a universal constant, that idea may not have gained any traction among aliens; similarly, they might not have brought any mathematicians along, or let them anywhere near the signal receivers. Their culture is *alien* to ours, so for all we know they drive their ships via religious zeal, with no knowledge of the divine mysteries of numbers.
The second problem with using mathematics to communicate is that it only goes so far. The only use for math as a form of communication that I've heard is as a confirmation of intelligence; if we met a vaguely humanoid alien at a party, we could show them some proofs to let them know we're smarter than the average primate, but we couldn't tell them our names, or define the abstract concept of a name. These things take context, and 'pure' mathematics is generally free of context.
Thus, I'd say mathematics can be used at best as a tool to begin communication, rather than the language to communicate with. You might be able to throw the Fibonacci sequence at them and hope someone recognizes it, but after that I think the first steps towards communication would be trying to get our natural languages to work rather than our mathematical ones.
[Answer]
The *concepts* of mathematics may be universal; I think that as far as we known, they are.
However, we do not *speak* mathematics. We use certain encodings: geometric forms, formulae using roman, arabic and greek symbols, and some other funky inventions.
While aliens with advanced technology probably have discovered the same concepts we do, they most certainly represent them very differently. So we have to think very carefully on how to communicate something that illustrates we understand a concept without defaulting to using an encoding only we can comprehend.
Some ideas have been put into objects we actually sent into space, e.g. the [Voyager Golden Record](https://en.wikipedia.org/wiki/Voyager_Golden_Record). See also [How Aliens Do Math](http://www.math.hawaii.edu/~jb/four.pdf) by J.B. Nation for some thoughts.
Demonstrating technology my be suitable to demonstrate mastery of underlying physics, and via that some mathematics. For instance, if we meet in space, both parties probably understand mechanics and relativity -- along with the corresponding mathematics.
But then, mathematics ultimately only serves to explain things in a model world. It is not inconceivable that other models exist which can explain the same phyiscal phenomena, but are not immediately compatible with ours.
That said, if you sit a human and alien mathematician plus some linguists of both sides together, I'm optimistic that they can figure out a way to understand each other. *Assuming* we both talk about the same thing when pointing at the moon, we can learn each other's encoding of mathematics.
We just have to not shoot each other for long enough.
As a reference in fiction, I loved [Story of Your Life](http://en.wikipedia.org/wiki/Story_of_Your_Life) by Ted Chiang for a believable tale of understanding completely different minds.
[Answer]
**Possibly.**
I would argue that math is a universal language as long as your *perceptions* are equivalent. So we could use it to develop communication with similar species, like star trek/star wars aliens.
But what about really, **really** different aliens? What if they only communicate and perceive scents, but at a level thousands of times more sensitive than any lifeform on earth? In that case we might be able to use math to decode and start understanding their language structure. But we wouldn't necessarily be able to use it to actually translate or communicate - their concepts could be so alien that starting with math isn't sufficient to jumpstart to other understandings.
[Answer]
The short answer is that we don't know.
There is an active field of [academic philosophy](https://en.wikipedia.org/wiki/Philosophy_of_mathematics) that deals with the underpinnings of mathematics trying to answer this question, and one of the more alarming notions to emerge from it is [Fictionalism](http://www.iep.utm.edu/mathfict/).
The gist of it that numbers (and thus math) are convenient conceptual tools that make it *easier* for us to describe categories of ideas, but aren't *essential* to do so. One of its proponents, Hartry Fields, went so far as to accurately and in detail restate Newton's laws of gravitation without using a single number or formula - [science without the math.](https://en.wikipedia.org/wiki/Philosophy_of_mathematics#Fictionalism) (Every highschooler's dream made nightmare by academic philosophy's rigor!)
Fictionalism is not widely accepted, but so far has proven very resilient to most of the arguments challenging it, so it's not crackpottery, either.
So mathematics may not be an absolute, because mathematics may not exist in and of itself outside our human minds.
[Answer]
I work as a mathematician. In many instances, the same mathematical idea seem to come up in different places, and independently. The most famous example is perhaps Newton vs. Leibniz with calculus.
This somehow shows that mathematics is universal in some sense.
[Answer]
Mathematics is universal. It was developed by observing the natural world (including things outside of our planet). One of the fundamental aspects of our understanding of the universe is that the physical laws (conservation of energy, momentum, charge, etc.) are equally applicable any where you are in the universe. Assuming that this is the case (we have never observed anything supporting the contrary) then an intelligent alien race existing in the same universe will necessarily have to develop the same physical laws that we have.
Whether or not conversation could occur, like "We come in peace", is somewhat of an ambiguos question. To illustrate my point consider a dolphin. It is entirely possible that a dolphin is intelligent and has the ability to, at some point in time, comprehend and develop the laws of physics (maybe in 10,000 years the dolphin will have developed the ability for space travel? It took us about this long to get to the moon). However, at this point in the history of the dolphin we have never really tried to start a conversation with it and likewise, as far as we know, the same is true for the dolphin. Indeed, it has only been recently that we have even had the ability to "hear" a dolphin (SONAR). It may be that in order to fully communicate with a dolphin it would take 20 or even a hundred years of intense study by many people in order to develop the skills needed. The fact is that a human discussing the complexities of calculus with a dolphin will most likely never occur since we have considered ourselves to be the superior intelligent race and have never really needed to interact with a dolphin on an "intelligent" basis.
Now consider an alien race that comes to Earth. We could try and make contact but they must be willing and able to listen. By ability I mean that the alien race must have some way of actually detecting our message, be it sent via sound waves, light waves, particles waves, or any other type of wave (sound for a dolphin). By willing I mean that they must not view themselves as the superior intelligent race since we can only assume that they would take the position we have with the dolphin. Provided that these two things are present then we would need to begin communication from a perspective that is familiar to both species. Since this species has travelled the cosmos to get to us it is not a bad assumption that they would understand physics and mathematics.
Note that we would also have to be willing and able to listen to the alien species as well (if they, for example, communicated with a beam of neutrinos, then we don't have the technology to listen right now)...
No matter how you look at it, it will take time to develop the skills necessary to communicate if communication is possible. Mathematics and physics, being universal, would be a good place to start.
[Answer]
How would we choose to convey the known relationship between the idea of numbers. Surely not computers or waves of electronic messages.
The best solution would be to leave large celestial objects coded in relationship to other natural objects within the vicinity where life MAY come to gaining the intelligence to decipher the improbable relationship, which would be designed to be unnaturally occurring.
The chances of two different beings from different planets, surviving and being alive in the same point of space time seems unlikely. But to leave a relic for the future to understand seems like the best mode of communication among the expanse of time.
[Answer]
There was a talk, perhaps in SETI Seminars, but it might have been elsewhere. I saw it on youtube.
The presenter showed particular esoteric and mind-twisting mathematical objects that had obvious 2D sketches representing them.
He points out that an alien might communicate a concept by saying "what this has"..."and this does not have". With different basis for approaching mathematics, or knowledge of those things through culture, it makes sense. But to us it would be baffling.
[Answer]
You don't have to go very far afield to encounter "aliens" that use very different math. The typical counting system for tribes in the Amazon is 1, 2, 3, 4, "many". That's it. If you tried to exchange differential equations with them, they simply would not care and find you incomprehensible. And when trying to communicate with these or other cultures with far more math in their knowledge base, linguists never resort to math as a "universal". The thing is, math has in it some universal things, but it does nothing for the concepts that language most often deals with.
Relationships, words like "peace", concepts like greetings and honorifics, expressions of concern, empathy, disgust, all of these are abstract concepts that have no correspondent in mathematics. A linguist trying to get the word for "friend" in another language will never use mathematics as a help.
At some point, in the collection of language data, a linguist will elicit numbers and ordinals, but that is a small, very tiny subset of language. Nowhere in the vicinity of being a language in itself.
[Answer]
There are many things not included, or not yet included, in mathematics. We have calculus now, but before a few centuries there was no calculus. Mathematics does not deal with biological decisions — it's just too complicated. Maths is only useful where it has applications. So, no, it isn't.
[Answer]
# Kind of
## Math itself is *omniversal*
While the exact representations, rules, and applications may vary, the observational strategy of logic within mathematics apply not only to this universe but can apply to everything in all universes.
Geometry in other universes might not be Euclidean, but that doesn't rule it out as being non-mathematical. It would simply be based on different assumptions. Technically spacetime is non-Euclidean so this is actually the case for our own universe, however, Euclidian geometry is still extremely useful at the scales we typically operate.
While unlikely or perhaps impossible, you might have some universe where 1 + 1 = 2 and 2 + 2 = 4 but 2 + 1 + 1 = 5, but that just means certain numeric axioms no longer hold. Beings in such a universe could conceivably work with a mathematical system that assumes associativity of addition of integers even if their world doesn't actually work like that. After all, we use imaginary numbers even though there isn't really a physical analog for their meaning. (Though they *are* useful for certain physical properties like electromagnetism) (As a tangent, there actually *are* mathematical number spaces where addition is non-associative, but I don't know of any that have a practical application.)
The only way math can be useless in some universe is if it is so chaotic that there is no consistency of behavior and there are no universal laws. Such a universe could not support structure, let alone life.
But bringing it back to just our universe, it's extremely unlikely that, say, prime numbers will suddenly stop working in some remote corner of the universe. Geometry and algebra will still work elsewhere. The rules are going to be the same no matter where you are in the universe or even what universe you are in.
## Notation is *not* universal
As far as communicating with aliens, the only barrier is representation. Humans have more or less agreed on the use of base 10 using arabic big-endian place-value numerals, symbols used for operators and common functions, using pi rather than tau, degrees, radians, and a couple of different notations for calculus (due to the Leibniz/Newton split). We've even decided on a binary encoding for all the symbols we ever would want to use. But all this was after thousands of years of development of humanity and most of the standardization has come in the last 500 years or so (with Unicode occupying the last 30 years or so).
Aliens almost certainly developed differently than humans, resulting in different representations of mathematical concepts. This wouldn't be a simple matter of different symbols to learn. For integers alone, there are hundreds of plausible notations from base, mixed-radixes, big and little endian representations, or even more complex representations of numbers like graphs. Real and complex numbers then multiply that further. Adding in operators, there are at least three plausible notations (prefix, postfix, and infix) if expressions are represented in a linear fashion. Expressions could also be represented in a tree structure. As you go through every mathematical concept, it's not unreasonable that you'll find some similar notation somewhere, but to have it match everywhere is extraordinarily unlikely.
] |
[Question]
[
I'm working on a story set in a world with a tri-gendered race of intelligent creatures, the protagonists in the story. I want to be able to explicitly describe sexual intercourse among other things. I'd love some suggestions on how this might work. Some questions are:
* What are the three different types of sexual organs and how do they fit together during sex? I envision that all three genders must make love together to be able to procreate.
* What might the sexual stereotypes be with the culture of these creatures?
* How should I handle pronouns in the story to be able to remain clear but not be awkward.
* How about child-bearing? Would one gender bear the child or would be handled differently?
* What kind of societal differences would there be between this culture and our own?
I know that Isaac Asimov explored this possibility in his novel, *The Gods Themselves*, but I'm looking for interesting ways to explore the concept further.
I'd love any ideas you might have!
[Answer]
It's pretty easy to have a genetic structure shared across 3 sexes and combine across the three. You could have either one lay egg or one carry after the three sexes combine chromosomes.
However, justifying the evolution of this species is harder. We have two sexes because we need a way to trade genetics; however, once you have some way to recombine genetics there is limited use for a third sex. If two of the sexes reproduce then each of their children has half their genetics if three reproduce then each child has 1/3 of a given parent's genetics. Once you have *some* means to add genetic variation the extra genetic variation of a third parent does not add much more to the overall genetic health of the child compared to two parents, and the loss of your child not carrying 1/6 if your genetics it otherwise would have is significant.
There is a strong evolutionary advantage to evolve to only need two of the parents if a three-parent system existed; more importantly, it's very hard to imagine a situation where a third parent would evolve in such a situation like this. It's very hard for *two* parents to evolve, but it's almost certain that a two parent system would develop before a three-parent system would, and once a two parent system exists there is little reason for 3 parent system to evolve.
This is relevant because I can not answer most of your questions until I know how the evolution occurred. If I can pick from one of a number of evolutionary options I can only then describe a plausible explication for genitalia, culture, and physiology of the species in question. Thus the first question, to create a believable world, is how could this evolve. Let's see our options:
**Hive Queen**
Have a hive with a queen mating with males and many drones that never get to mate. In this situation, it's possible for a gender to evolve that does not benefit from spreading its own genetics, but from supporting it's 'queen' from spreading her genetics. In a situation like this one parent may share little or none of its genetics directly with the child; but it's a child, or close genetic relative, of one or both of the other parents and thus gains from helping them.
Imagine a female queen that has male drones to mate with and a 'brood' sex that carries the child produced from the male and female mating to term, but does not contribute any genetics herself, being just a uterus for carrying children to term. The brood sex will be a close genetic relative to the queen, either daughter or sister, and thus shares 50% (or possible [up to 66%](https://en.wikipedia.org/wiki/Haplodiploidy)) of her genetics with the queen. By helping her queen produce lots of children the brood sex benefits from spreading her queen's genetics even though she herself does not spread her own.
The female may produce lots of these brood-sex children, possible many dozens. As each of these children births, one match of young the queen will summon her up to mate again with the queen and her male, to produce a new batch of children. Eventually when one of the brood sex dies the queen will choose to produce another of this sex to replace the lost one.
The big benefit of this approach would be that the queen can produce more children at once. With a traditional queen situation, a queen needs to produce lots of eggs, which requires a massive caloric intake and a huge body for processing these calories and translating them into young. With a brood sex the queen can force the brooder to put in all the caloric investment to carrying her young, and she can have dozens producing young. This makes it easier to provide nutrition to each one-the queen is spatially limited in her ability to have kids because she can only convert honey to eggs so fast, but she can always add more broods. This also means the queen can stay small, and thus mobile, instead of being a huge thing in the center of a hive that can't move. Perhaps a queen can even have multiple hives that she flies to long enough to impregnate each of her brooders, before flying back to the first hive (though this would make her vulnerable to predation; this could still work of new queens are always ready to replace the first when she doesn't come back and may add to the genetic diversity of the hive if it's forced to replace its queens on occasion?
The downside is that each of these brood children requires extra calories since multiple 'brooders' is not as efficient as one super adapted queen producing all the young. Thus this would only work in situations where producing *lots* of young quickly was more important than conserving resources, and it's hard to imagine this being the case often. Perhaps if the hives were mobile, one hive would set up and consume the resources in an area quickly, then break up and fly away to set up more hives. The ability for a queen to start a hive full of brooders while she travels to set up a new hive may be useful.
There are a few ways to handle sex in this format, depending on how the queen and the brooding sex differ (the standard male role would be pretty much as it already exists).
1. The queen may serve a role closer to male and simply providing more genetics to the brooding sex, being unable to produce any children without a brooder. in which case the queen would need to be provided brood sex 'sisters' from her mother when she starts a new hive; replacing these brooders with her own daughters as they die out. This seems least likely since it means the queen and hive are worthless without brooders.
2. Alternatively, the queen may be able to produce only brood sex children herself, but nothing else without a brooder. I could only see this if a queen could produce both brood sex *and* males, and is using a system where she can start a hive by herself by birthing the original ones [in a Haplodiploidy system](https://en.wikipedia.org/wiki/Haplodiploidy), but needs both sexes to produce new queens.
3. Most plausible, the queen could carry any child to term herself but prefers to use brood sex whenever possible (possible in conjunction with Haplodiploidy system above). The queen's first mating may have her birthing some males and brood sex children herself, then from that point her she uses her brood sex children for all matings.
The reason I consider the third option to be the most possible is that it's the most likely to evolve. As I said a 3 sex system is hard to justify, but in this case, the 3 sex system is an obvious offshoot of the traditional 2 sex system. The brood sex may be genetically very close to queens, except sterile by themselves. They evolved as queens that were intentionally kept sterile by their mother and exploited, eventually evolution causing them to diverge as more unique sex. The queens retain the ability to birth young (be it egg or live birth) the same way the brood does, but the brood traded ability to generate eggs for an ability to carry more eggs to term etc.
To answer your questions in this case the brood would likely be referred to either as it or with female pronouns like the queen. Since the brooders would not be given much attention, and likely wouldn't be intelligent, it will not be confusing to use the same pronouns as you use for a queen, any more than calling both your wife and your dog 'she' would be confusing.
Both queen and brood sex would have very similar genitalia. I imagine the females (both sexes) would have an ovipositor that can be inverted to act as an oviduct. TO give a rough analogy something like a 'vagina' that can be pushed out to act as a 'penis' for ejecting eggs into the broodmare. Both the queen and broodmare would have very similar structures, even if the broodmare never ejects eggs into others.
Culturally the broodmare doesn't count as anything of importance. You have females and males, and biological things that their child is growing in.
**Shared parental investment**
Have three independent sexes, which all invest equal effort into raising the child. It's important that they all contribute equal effort, if they do not it becomes hard to explain how this is an evolutionary advantage, since one sex gets to spread their genetics with less expense; which works in our world only because the advantage of sexual intercourse is so high that females are willing to pay a disproportionate expense to have sexual reproduction; once you already have at least two sexes reproducing sexually there is no reason for allowing a third sex to contribute less effort but get the seam genetic benefit; that would be evolved away on the grounds that you can do two-person sex without the free-loader.
There are many ways to get an equal genetic contribution, though most approaches favor R select species which are unlikely to evolve sapience. Here are the key ones I can think of.
1. With R species all three work together to produce a large batch of eggs somehow. The energy investment for each sex is about equal in producing the eggs. and the eggs are then left alone to produce lots of young without further parental investment.
2. Close to one, each sex takes turns in raising the young through a phase. sex X produces the original eggs which it transfers to sex Y, likely through some form of internal fertilization, at a minimum to an egg pouch similar to what seahorses have. sex Y fertilizes the raw eggs and carries them partially to term, long enough for the eggs to develop a hard shell and be safely 'layable', ie able to survive outside of the body of X or Y. Y then lays the eggs so that Z can fertilize them. Z then protects the laid eggs from predation, sitting on them, protecting the clutch etc, until the eggs hatch. At this point, the children are mostly forced to fend for themselves.
3. In a more K select species, one sex produces large, caloric expensive eggs, that it passes off to the other two sexes. The other two sexes fertilize the egg and then work together to raise the young. The put little caloric investment in going from embryo to born child, but the invest the effort in raising that child to reproductive success. Though this seems least likely, it's the one most likely to create sapient species.
4. All species 'conceive' after intercourse. Perhaps three 'eggs' (very underdeveloped) are produced from intercourse and each sex will take and care for one of the produced young, with the primary investment being parental care raising the egg to adulthood, not in the production of the egg itself. Why you would have 3 sexes instead of one (see below) in this situation is hard for me to explain though. In terms of intercourse, I would probably do something like what I had in 2 though. Sex X and Y have internal fertilization/intercourse to produce 4 large 'layable' eggs, X and Y both take two of these eggs. they both find a sex Z and have intercourse with it to fertilize their two eggs again, and both sexes walk away with one fully fertilized egg to care for.
Your notice in all these situations I suggest that the sexes have intercourse at separate times, and that sex X may never know the sex Z that fertilized their egg, this is intentional. It seems quite difficult to justify an evolution where 3 sexes have to agree on each other as a mate, what if the X doesn't like the Z but likes the Y? how do per-sapient sexes handle mate selection and decision making? It's more plausible if each sex needs only pick a single mate at a time to have intercourse with, even if another's DNA will be added later. This also justifies the *only* evolutionary advantage I can think of for 3 sexes if there is a reason to delay the development of the full child. Perhaps environmental factors can cause embryos to fail to form early, so having a phase of partial-development (after X and Y mate) allows one to see if the children will successfully develop or die due to undesirable mutation/chromosomal damage, prior to final fertilization and the completion of a child developing.
It's possible that in sapient species sex X Y and Z will all know each other, but the original mating habits likely evolved around X never knowing Z, and it's only with later sapience that interest in knowing the full genetic investment in the child lead to X and Z meeting.
In terms of pronouns, I think you would simply have to create new ones for almost all of these, such as the way I said sex X Y and Z.
In terms of genitalia, I would imagine all have very similar genitalia, with only minor differences. They should all look similar since they have to all evolve from a single format. I can't say more without knowing which of the above options were used.
These systems would likely lead to R strategies where parental investment didn't exist, and thus no sapience. For the ones that lead to parental investment originally I would imagine each would raise their own child, but eventually, cultures may move towards all three sexes living as a family unit.
**Hermaphrodite single-sex species**
Finally, there is a third option which I consider far more likely from an evolutionary standpoint, which may still meet your needs. Have only one sex!
Instead of multiple sexes, which as I said are really hard for me to see evolving, have one sex, but which is capable of mating with multiple individuals of the same sex and producing a single child that shares DNA with three, or more, parents
With a system like this, you could claim that DNA can be split and recombined safely in more then than just binary manner. Perhaps each chromosome can be received from a different mate, or even individual chromosomes are broken into smaller gene sequences which can be split and recombined to combine genetics of multiple mates. This is not an impossible system, I think even our current DNA could evolve to an approach like this without too much hassle (potentially a minutely higher chance of birth defects, but the genetic fitness of multiple mates could more than make up for that), and a system that encodes genetics differently then DNA could definitely evolve for an alien species where this makes sense.
There is a genetic advantage to having your child contain DNA from multiple parents, the more genetically diverse a child is the more 'fit' he is on average, but the advantage is only so large. For the mother to benefit she must make sure she is still ensuring that half of her DNA is inherited from each mating she performed, otherwise she loses from the mating. There are a few options for handling this:
1. Your child always caries half your DNA. When mating with others you recombine their DNA to form the other 50% of your child's DNA. Since the mother always provides half the DNA it never hurts her to mate with more mates, and she actually gains more genetic diversity the more she mates with others. In addition any mating the mother has allows her to provide DNA to the female she is mating with, potentially contributing some DNA to her mate's child as well. There would thus be major motivation for females to mate with multiple partners, expect a very 'free love' society.
While it's possible to limit the mother to being able to only mate with 2 mates per child, with a system like this it feels more natural to allow many mates to all contribute DNA to the child, Once the mother has the ability to recombine DNA from multiple 'fathers' why should she stop at two?
However, since each 'father' may very well only contribute as little as 1/10 or less of DNA to a resulting child the father would not be inclined to provide much, if any, parental investment into the children of a mother. Thus this race would likely consist of all single parents.
Insects already have a variant of this, in which they produce many young with each young having potentially different fathers, so look at them for mating adaptations. Most noticeable it's likely that each mother will have some degree of control over how much, or if any, of a mate's DNA contributes to that of the child. This control may be conscious or subconscious. It may be that a mother attraction or pleasure with a mate will result in that mate's DNA being a larger percentage of the child's DNA; but that they mother has not direct conscious control over this factor. How much control the mother has in the percentage of DNA shared will effect mating behaviors.
In systems like this sexual mating may be traded socially. Look at the bonobo, who use sex as a social feature. A mother may mate with lots of others to please them. If she has strong control over who's DNA is used for the child she may mate with everyone to obscure her mate choice. If she has less control (ie any mate will likely contribute at least a little DNA to the child) she may be more selective with mates, but may be willing to mate socially with someone who has earned the right, through gifts or favors. In any case since any father only contributes so much DNA it's safe for her to be less selective about mates, the less control and the more DNA the child will potentially posses from any given mate the more selective she will be.
Pronoun wise you would have mother and daughter, and that's it. You may use 'mate' to refer to those that mated with your mother, but since the child of a mother may have little if any DNA of a given mate the concept of father doesn't really mean much. sisters will exist, but only if they share a mother.
Genitalia wise you have your standard penis and vagina. Or possibly an organ that combines the two together to allow simultaneous transfer of sperm to both sides.
2. Mother only provides 1/(mates + 1) dna to the child (limit to only 2 mates)
This gets back to the situation where it's less advantageous for the mother to mate. If the first mate produces a child with 1/2 of your DNA, and mating again produces a child with 1/3 of your DNA then there is little incentive to mate a second time and have a child with less DNA, usually. One easy way to fix this is to force mating to be mutual. If a mother mates with another female they are both guaranteed to conceive a child that possesses the mates DNA.
This works because each subsequent mating allows the mother to spread more of her genetics to the next generation, even if the child she is carrying possesses less of her DNA. Say after the first mating she will conceive a child with 1/2 of her DNA, and she chooses to mate with another mate. Her child will now possess only 1/3 of her DNA, however, her mate's child will possess wither 1/2, or 1/3 (if her mate has mated with another) of her DNA as well, meaning that The subsequent mating has resulted in her child having 1/6 less of her DNA, but another mate's child having 1/3 of her DNA; that's a clear benefit to the mother.
However, if the mother can mate with an infinite number of other mates she reaches an odd point, where she doesn't care about her own child. Once she has mated with 9 mates her child only possesses 1/10 of her DNA, and thus is barely close enough to warrant caring at all; she is more interested in the other 9 children who also carry 1/10 (or so) of her DNA. This makes for a rather odd, and eventually unstable, mating solution.
The easy way to fix this is to limit the number of mates a mother can have, in fact a system like this would almost have to place a limit on total number of mates; otherwise matings become so common that there is little intensive to care for your own child and things would evolve to an R select strategy of having dozens of young and tossing them into the world to fend for themselves.
So, say the mothers can only mate with a total of 2 other mates, this is as much as DNA can viably combine. Now each mother benefits from having two mates. IF the mother only mates once she will have one child with 1/2 her DNA and one with 1/3 (most often, if her mate has a second mate) or at most 1/2 her dna. A mother who mates twice passes on either 100% or 5/6 of her DNA to the next generation, depending on her mates mating habits. A mother who mates with three mates has *at least* 3 children that all cary 1/3 of her DNA, so she at minimum passes on 100% of her DNA, and there is always a small chance of passing on more if one of her mates doesn't find a second mate.
In addition the 2 mate option means more genetic diversity over one mate, meaning 2 mates is still beneficial over mating with a single mate who will not mate with anyone else. Plus, since you can never be sure your mate won't try to mate with someone else later making sure you mate twice means you come out ahead no matter what your other mate does.
This system is, again, plausible to evolve. Though a 3 mate system (meaning that DNA is split into 4, which is more likely due to it's being divisible by 2) may be more likely then a 2 mate system. In this system a mother may be a single mother, or one or both of the mates may stay to raise their children as a family. Occasionally two mates may choose to have a child together without involving a third mate as well, far more common once the species reaches sapience.
This system would lead to mothers being *slightly* less sexually selective then females in most mating situations of today, but still nearly as selective.
For this system to work there *must* be a pretty strong promise of conception occurring with all mates, which adds a potential complication. Females would have to be able to conceive very soon after mating, with very clearly defined mating 'seasons' during which they will conceive if mated. More importantly, and difficult to evolve, a female would need a way to advertise once she has conceived, say by swelling going down, as soon as she accepted her third mate. If this didn't occur then a female could mate with other females after accepting her third mate and impregnate them, spreading her genetics, while effectively ignoring their DNA offered to her since she already conceived.
There would be very strong evolutionary advantage for a female to evolve a way to avoid conception from a mating, or simply to mate after she has conceived but is not yet showing. To 'trick' other females into agreeing to carry a child with part of your DNA while you don't accept the need to carry any of their DNA allows you to mate with many females, and potentially spread far more of your genetics. This is a bit of an issue with this option, making it less likely to evolve; or more accurately to be evolved away from not too long after it's original evolution as people start finding ways to 'lie' about their mating.
This could be fixed with a monogomous mating system, where mates all know and watch each other. Thus a mother may choose to mate with a second female only if she can watch the female and verify the female does not attempt to mate with more then two mates. If a female does manage to sneak a third mating she will benefit from spreading her genetics to more, at the expense of her first two mates (who may share less or none of their genetics if she mates with a third mate).
This monogomy could take two forms. One is which all three mates choose each other and mate year after year. As I said above this is harder to manage in non-sapient species, but not impossible; and it's more justifiable when everyone is the same sex; making it easier to choose any other female as your third party mate. In this case the females would likely mate between themselves and raise their young as a third person family.
Another option would be that a female will stay close enough to watch her mate, but not try to control her mates selection of mates. Effectively female A will declare she mates with B to everyone. When female C comes by B may choose to mate with C, which A will allow; but if B ever tries to mate with a third female both A and C will protest since they are aware of her two chosen mates (A would have advertised to C that she already mated with B). meanwhile A and C may choose mates of their own. B will watch both of them and ensure that A and C only choose one other mate, but does not try to prevent or control who that third mate these two choose is. This mating strategy works best when everyone mates in a nesting area (or village) where it's easy to watch your other mates. Perhaps A B and C will nest closely together and each will contribute to helping raise B child partially, while also focusing partially on raising their own and their second mate's child. This sounds complex, but I think it could evolve to work pretty well. Each female has incentive to stay near both her mates, because both mates contribute partially to raising of her young, so it's easy for those mates to watch her to ensure she doesn't mate again.
Genitalia wise you would likely have some system that allows sharing of sperm by both mates at the exact same time. I would guess some sort of 'dual plug' system, effectively the same as inserting your penis into her vagina the same time she does the same to you. The positioning of the 'plugs' would have to make mating easy though. Mating from in front would be preferable then behind (behind makes more sense when the male and female roles are separate, due to female having more of a need to 'defend' against unwanted matings then male). I imagine their organs would simply be more flexible to allow repositioning to align up with someone your facing.
Pronouns work as above, everyone uses female pronoun but mother is limited to the female carrying the child, while those females that mated with the mother are considered father's of the child the mother carries. Yes that means a female can be a mother and a father. Siblings would get complex terminology. you can have third and 2/3 siblings (probably a more convenient way of saying 2/3 sibling will evolve). You may have two words for sibling, one for "we have the same mother " and one for "we don't have same mother, but share partial DNA" as well. Thus you can have third, partial, and full Sisters (share mother), and third, partial, and full siblings (different mother).
In a system like this some degree of parental investment will occur from all mates for each child, since it's almost as useful to care for your partner's children as your own since theoretically all three Cary 1/3 of your children (though not quite as much, since you can never be 100% certain cuckoldry didn't occur with partner children).
Culturally I imagine there will be both 3 parent homes where the parents only mate with each other and raise children together, single parent homes where a parent raises their child alone without aid or investment from the other parents (less common), and shared communal homes where people work together to help raise children.
The communal homes are most interesting. Take my example above where A and C mate with B. Now imagine A also mates with D, and C mates with E, and for the sake of simplicity C and E happened to mate. Now you have a group of 5 parents that all share children with two other parents. The parents would all prefer to stay close to their other two mates, which could result in all 5 mates living together.
Now imagine if it got more complex, you could have 10 or 20 mates involved in a chain before the chain of matings 'loop back' by having someone mate with two people already in this mating chain. You may tend towards large communal living spaces where everyone tends to contribute and share parental care of children, but of course they all mostly focus on the children the sired. I think the entire species would evolve to have more of a 'community raising the child' mindset due to this bizarre spreading of genetics. How much this is true depends on how monogamous the species is.
Speaking of which, this species could be highly monogamous, or each mating season it could mate with different couples. I would imagine it would tend more towards monogamy, as it would make it easier to share parental investment of raising multiple generations of children at once, but it need not be mandatory.
This species will most likely have mating seasons or some similar concept, everyone becomes fertile at roughly the same time. That's required to make watching your mate and ensuring they only mate with one other mate possible.
[Answer]
# Diachronic hermaphrodites
I’ll offer a variant of @dsollen’s “hermaphrodite single-sex species” which I also think is more likely to have been evolved than three separate species.
Life on Earth started without differentiated sexes and many lifeforms still make do with just one sex (which is the same as none), but mixing the genetic code of two (or more) individuals seems to give some evolutionary advantages, especially for more complex lifeforms. Social patterns developed accordingly. Evolution didn’t have to create two distinct sexes and assign each individual to one of them once and forever. Some organisms are hermaphrodites, i.e. they have both kinds of genitals, but usually, they still require a mating partner to produce offspring. Other species can change sex once if necessary (e.g. remember the hand-wavey explanation in Jurassic Park), others even multiple times.
I’m suggesting a species that cannot change sex at will but will instead go through several sexual phases throughout its lifetime.
1. After birth (or hatching), **kids** are *presexual*. Genitals are almost female, though.
2. With puberty, **youngsters** become *gynsexual* ‘female’. Their ovaries fully develop and start to produce eggs. If they are mammals, their breasts grow and can produce milk after giving birth.
3. With menopause, **adults** become *intersexual*. While they may still enjoy having intercourse, they are not fertile. They mostly care for the offspring they have born, support their family or larger parts of society (incl. being soldiers).
4. With transition, **matures** become *androsexual* ‘male’. Their testicles and penis (or whatever) have grown and are fully functional. They can mate with youngsters. Since there are by design less matures than youngsters and their role is about to change anyway, long-term monogamy is unlikely, but they will probably somehow nourish their first and second phase offspring anyway.
5. Finally, **seniors** become *postsexual*. They lose all their reproductive capabilities but are more like a man than a woman. Their bodies can focus on other organs, including the brain.
Please note that this sequence may seem like a hierarchy which suggests that males are worth more or higher advance than females, but I chose this order just because first, pregnancy is stress for the body and should be left to the (relatively) young and healthy, and second, the parent is then more likely to live afterwards to raise their children. I like the idea that every ‘man’ has to have gone through being a ‘woman’, so these ‘men’ are very differently socialized than us human men.
I don’t think language would develop grammatical gender distinction as we know it, but there certainly will be simple and exact words for the different phases of life and family relations, maybe also age-based honorifics. Culturally, I assume, there would be several rites of passage for everyone.
I tried to come up with estimates as to how long each phase should last, but I really can’t offer anything better than, in Earth terms: ten years each at least.
# Three-sex arrangements
Most variants I can think of have probably already been presented, I lost track of ideas:
* **Mediator**: Male inseminates bigenital ‘cogenitor’ (i.e. looking like a hermaphrodite). Cogenitor puts fertilized egg inside female (cuckoo-like).
+ Variant: Cogenitor puts modified sperm inside female (catalyst).
+ Variant: Male could also impregnate female directly.
+ Variant: Cogenitor could impregnate another cogenitor, i.e. act as either male or female.
+ Variant: Cogenitors could impregnate each other, i.e. act as male and female at once.
+ Male and female could have developed from the cogenitor as common origin.
+ Cogenitor could be a different, symbiotic lifeform – or a medicinal robot.
* **Breeder**: Amale and bemale inseminate female, only then one of her eggs can get fertilized.
+ Variant: Amale and bemale are not different sexes, but still different male individuals.
+ Variant: Even more kinds of male required/possible.
* **Donors**: Amale sperm-donor and bemale egg-donor both inseminate cemale breeder in whose womb an egg gets fertilized and grows.
* **Incubator**: Male insemninates female as usual. Fostress extracts embryo from female (e.g. female lays an egg, or the baby gets born prematurely, kangaroo-like pocket).
+ Variant: Just two genders, but males have the pockets and probably breasts to feed from (seahorse-style).
* **Hermaphrodite**: Male can inseminate uter or female. Uter can inseminate female (with its own, unaltered sperm).
By the way, if you just want to justify a promiscuous, polygamous two-sex society, make fertilized eggs not able to nest inside the womb of the woman whose ovaries the egg came from. Like **pollen**, they would attach to some pocket in a penetrating penis and remain there until they are released into a different vagina.
[Answer]
When I speculated (unpublished) on aliens with 5 sexes, I figured the material being shuffled was in 5 parts, rather than 2 copies like ours. Two different nuclei each with 2 gametes, and an egg with mitochondrea and other asexual information. Late merger of eucaryote-style endosymbiosis *after* sex evolved kept them from merging, and the same species has different more-drastic phenotypes than our minor diamorphism.
Three is easy in comparison. You need a reason why the egg isn't also a bearer of chromosomes but the roles are kept distinct. Perhaps more (important) functions of organelles like mitochondrea and chloroplasts.
Maybe the *cell level* information is present in various organelles and sexual recombination takes place between individuals with different eggs, and this is important for disease resistance and metabolism that quickly adapts. Meanwhile, a nucleus is used for multi-cellular organism programming (only) and has its own two gamates, and this reassortment is used for evolution of the phenotype.
Note that *recombination* and *reassortment* are different mechanisms. Working in different ways helps keep the different steps from merging in a more streamlined manner.
Also, the first kind, cell-only information, is like bacteria that swap genes without having clear cut species as a concept. This type might be available *across species* in that world, which helps pick up immunity faster if long-lived species can learn from short-lived ones. The second kind of sex is specific to (and defining of) individial species in higher-order life like plants and animals.
---
Turns out, real biology is more varied than I realized! [*Tetrahymena thermophila*](https://en.wikipedia.org/wiki/Tetrahymena) has **7** sexes that can reproduce in 21 different combinations. Cells have two nuclei, just as in my story.
[Answer]
I wanted to come up with something that's not a variation of Niven's Puppeteers (two sentient males and a non-sentient female incubator).
So there are three genders that come together, but they don't have intercourse. Instead one of them makes an egg while the other two help form it, and then all three inject their reproductive cells into the egg.
So the cells from one parent will join with cells from either of the other two, but will be dominate with one, and recessive with the other.
Let's label the cells Red, Blue, and Green.
Red + Blue = Red
Blue + Green = Blue
Green + Red = Green
They all mix and combine, and which ever has the most cells at the end determines the gender.
Tl;Dr: So the cells roshambo (rock paper scissors) for control of the gender.
Edit: you could still have live birth with one of the genders acting as female, but I can't really think of a genital setup besides the male/female arrangement we have for delivering reproductive cells into a womb. So it would end up as male and different male, aka Puppeteer.
Edit 2: Taking Greens suggestion of a Cloaca into account, you could have live birth that way, where they have seasons where they switch from being a contributor to being a carrier. So for part of the year they are able to donate genetic material, and part of the year they receive it and give birth to the young. Then whichever they mate with would determine what the gender is at the end, while avoiding the Puppeteer problem.
[Answer]
Since you specifically want three genders, the problem is encoding three genders in genome in a stable and meaningful way. I think the easiest way is to make the species triploid with XXX, XXY, and XYY equivalents each being a separate gender.
The way I understand it evolutionarily triploidy is a response to unavoidable environmental exposure to radiation or toxins. It is common in immobile plants and animals bound to relatively small habitats that can become contaminated. It is also seen in otherwise diploid organisms in specialized organs that are continuously exposed to radiation, toxins, or oxidative stress.
Of these options most likely would be evolution from an amphibious species that was triploid in order to cope with possible contamination of small ponds and lakes it lived in. Further we can assume triploidy comes from dual fertilization of the egg. The other alternative (two copies from the mother or digyny) is actually more likely, but since it can't lead to three genders we can ignore that.
Having genes from two fathers gives higher genetic diversity than being fertilized twice by the same father, so it would seem reasonable to evolve a gate system that prevents double fertilization by the same father. The start would be a system that requires a certain time since the first fertilization before the second can happen. If only one male was available both fertilizations would still come from him.
The remaining problem is differentiating XYY and XXY into separate genders. This should start with the original differences. XYY would have more male hormones, while XXY would have an extra copy of the X chromosome. We can assume (no basis, but we can) that this means the XYY males are more aggressive and stronger and XXY males have longer lifespan.
We can then assume the evolution of a social structure where all three groups have separate roles. XXX would specialize in reproduction and child care. XXY with its longer life span would do food gathering from the area and later tool and shelter manufacture. XYY with more aggression, higher strength, and higher expandability would do scouting, hunting, and conflict with competitors.
If we assume live birth (to make them more like humans if nothing else) this gives rise to sexual trimorphism. XYY would be larger with more robust bones and exaggerated musculature. XXX would have wider hips to facilitate live birth. XXY would probably be smaller and more social.
Note that by default half the children would be XXY with quarter each XXX and XYY. Lack of pregnancies and lower aggression would also give lower mortality. So the majority of people would be XXY. As XXX and XYY are relatively as numerous we can assume permanent pair boding with opportunistic sex with XXY. XXY would be bonded to the larger tribal group, not to any specific XXX/XYY couple.
Since the XXY are neither aggressive nor targets of aggression nor permanently pair bonded, the most likely system for gene transfer between tribes would be with the XXY moving between groups. Triploidy should give higher resistance to inbreeding, so the level of movement could be low and different tribes might be quite different.
With the two types of males having different sexual patterns XYY with permanent pair bonding and XXY with opportunistic social sex differentiation to separate genders is practical. Since the two males are hormonally different evolving a system that restricts the first fertilization to XYY and the second to XXY would be practical. The benefit would be in binding the both types of males to the children genetically.
The two types of males would have the same male reproductive organs with the same function, the female would have normal female reproductive organs. Details would vary based on the specifics of the species. While I am assuming amphibious omnivore here, that could mean a mammal, amphibian, or reptile analogue. Or something entirely different.
I hope this answer gives a plausible, if unlikely, route for the evolution of a tri-gendered species. I think the other questions in the original question should be dealt separately in other questions with more details of the species given. Although the evolution I suggested does require specific social pattern to drive it.
[Answer]
First off, [wikipedia](http://en.wikipedia.org/wiki/Sex_determination_system) is awesome for generating ideas about this. The following is an amalgamation of existing methods for sex-determination.
Most of the answers are predicated on the idea of a 2 sex gene structure/"fight for dominance." Adding in a third sex gene provides another way for this to occur. This could be either as a "third partner" in direct intercourse that is vital to the gamete formation (either adding the egg with mitochondria or a distinct type of sperm), or as a host where the gamete picks up genetic material from the womb once implanted (I lean toward this one). In this latter case, the third partner (P) takes the fertilized egg *from the female* to implant in their own womb. This is all dealing with a roughly humanoid/mammalian race, otherwise all bets are off. You could easily appropriate an existing [non-gendered pronoun](http://en.wikipedia.org/wiki/Gender-specific_and_gender-neutral_pronouns#Alternation_of_she_and_he) for this third gender. I like to use phe as it's audibly distinct but relateable to existing he/she pronouns.
In humans, [aneuploidy](http://en.wikipedia.org/wiki/Aneuploidy) in general leads to mutations, some of which are harmful or fatal to the fetus. For sex chromosomes, though, trisomy leads to [Triple X](http://en.wikipedia.org/wiki/Triple_X_syndrome) for women and either [Kleinfelters](http://en.wikipedia.org/wiki/Klinefelter_syndrome) (XXY) or [XYY](http://en.wikipedia.org/wiki/XYY_syndrome) for men. None of these really pose any genetic problems to reproduction. So we know trisomy isn't problematic.
So let's assume this species requires trisomy for sexual determination. Now what? We use a modified [Z/W methodology](http://en.wikipedia.org/wiki/ZW_sex-determination_system) (like birds) to determine which of the three genders the child is.
If the child has a ***majority X***, they're genetically female (relevant point: those who are XXY Kleinfelter syndrome tend to have gynecomastia). If they are ***majority y***, then they are male. These both fall under ZW. If they are ***either XXX OR YYY*** then they are the third gender (let's call it phee) —ZZ determination.
There are 8 possible combinations:
XXX (P)
XXY (F)
XYX (F)
YXX (F)
XYY (M)
YXY (M)
YYX (M)
YYY (P)
Since all partners will have X's (for an XP) or Y's (for a YP), there is a chance for all three genders out of any particular tripartite union. You'd think this is a 25/37.5/37.5 split between genders, but that's actually not true. Statistically, let's map it out:
P= either 100% X or 100% Y. Assuming there's no genetic testing or externally expressed sexual characteristics to distinguish between them, then it's 50/50.
M= 33% X/67% Y
F= 67% X/33% Y
So M/F has a 22.2% chance of contributing XX and 50% chance of P being X, yielding an 11.1% chance for PX and an equal chance for a regular F. The same split is true for YY, so the total chance of P(X or Y) = 22.2%. This is absent pre-implant genetic screening (so you can pair XX to a PX and YY to a PY), which could potentially double this to 44.4% (so your XX/YY is ALWAYS paired to a matching P). In this case, P is the determinant between (M or F)/P.
M/F XY gametes happen the remaining 55.5% of the time. In these cases, the P is the 50/50 determinant between M/F (since P is already not an option).
So our real gender splits are:
M=F=27.7%+11.1%=38.8%
P(x or Y)=22.2%
After gamete genotyping becomes available, this will shift to 44.4% for P, and 27.7% for both M and F. The implications of this will be discussed below.
As you can see, P's are rarer than either M or F, while still being reproductively necessary. This will make them culturally and socially desired. How exactly this effects society depends upon the physical characteristics of the P. Assuming that the P is the gamete carrier (the M fertilizes the F and the P takes it from the F) and consequently the child birther, we would assume evolution would incentivize frames with wider hips and a more muscular lower body (for both fleeing to protect the fetus and for muscle tone in carrying/birthing the fetus). This is related to, but a bit different from, current female sexual characteristics.
With male-female pairs competing for the favor of a P to birth their young, P's would likely find themselves in positions of authority where they get to choose favorites - think judges, shamans, and the like. It's likely this would impact how families get structured, with They would become symbols of fertility. The birth of a P child would be seen as a sign of favor from the gods, and such children would be pampered above others. Due to "gender typing," the M would "socially" educate the M children, the F to the F children, and the P to the P children. This stovepiping, along with their favored status, means that P's will get more educational and cultural opportunities than their biological M & F siblings.
With the advent of gamete genotyping coupled with the cultural favoritism toward Phees, you'd expect that M/F couples would, when given the choice, choose to have a P over a M or F. This will quickly lead to demographic saturation (P's will be 44% of children born rather than 22%). What happens at that point depends on how culturally important Phees are as a whole (vs. as "special" individuals) and how their "modern" families are structured (are Phees another parent or a surrogate to a M/F pair like mentioned earlier). This could lead to a Phee master/(M&F) slave society. Or not.
Really, without having more concrete material to work with, the question of "what are the implications" is way too broad a question to answer...
[Answer]
To simplify this I would make it similar to human gender
```
-Female
-Male
-Female/Male
```
**The Female:**
it can get pregnant.
In order to get pregnant the female needs two different DNA sperms:
```
From male and male. (half each)
or
From male and female/male. (half each)
or
From female/male and female/male. (half each)
```
**The Male**
It cannot get pregnant it can only give sperm. half of DNA needed. so that in order to get a female or a female/male pregnant he needs :
```
his sperm plus the sperm of another male (half each)
or
his sperm plus the sperm of a female/male (half each)
```
**The Female/Male**
it can get pregnant but also can give the half part of sperm needed to get a female or a female/male pregnant.
in order to get pregnant the female/male needs:
```
a male sperm plus the sperm of another male (half from each)
or
a female/male sperm plus the sperm of a another female/male (half from each).
```
In order to get a female or female/male pregnant the female/male needs:
```
his/her female/male sperm plus sperm from a male (half each)
his/her female/male sperm plus sperm from another female/male (half each)
```
**Female result:**
```
from pregnant female with sperm from male and male
or
from pregnant female with sperm from male and female/male
or
from pregnant female with sperm from female/male and female/male
or
from pregnant female/male with sperm of male and male
or
from pregnant female/male with sperm of female/female and female/male
```
**Male result:**
```
from pregnant female with sperm from male and male
or
from pregnant female with sperm from male and female/male
or
from pregnant female with sperm from female/male and female/male
or
from pregnant female/male with sperm of male and male
or
from pregnant female/male with sperm of female/female and female female
```
**Female/Male result:**
```
from pregnant female/male with sperm of female/male and female/male
```
**Organs:**
```
female has one vagina and sperm donors can take turns,
or 2 vaginas and the sperm donors can be in her at the same time.
male has one penis.
female/male, if regular female has one vagina then female/male has one
but if female has 2 vaginas then female/male has 2 as well,
and has one penis regardless of 1 or 2 vaginas.
```
In your story you might say that because to have a **female/male** born all 3 parents need to be **female/males**, the `female/male gender` look down to female and male gender, and think that a female/male gender is superior.
```
You might call them female, male and fema.
```
**EDIT**
```
Females are the most beautiful.
Males are the strongest.
Femas are the most intelligent.
```
The typical scenario is that the 3 persons live together as a triplet and raise the child together, but some might "divorce" taking one person out of the triplet and might bring another person to join the couple to make it a triplet again, or they might choose to live as a couple instead which is not typical in their culture, or a single person might raise the child alone which is less typical and almost insane in their culture.
love unions of triplets is the norm, and partners of more than 3 like 5 or 9 its not bad viewed as long as they are all female/females.
[Answer]
If you have three sexes, and only two of the three are required for successful production of fertile children, then it's only a matter of time before mutation makes one of the three sexes vanish. The species can carry on without them, and it will. Nature does tend towards simpler designs, if they get the job done.
So you do need three sexes. One possible set-up is a race with triploid chromosomes. Each gender contributes a gamete with one-third of its chromosomes. Transferring a fertilized egg (or partially fertilized egg) is fraught with difficulties, so instead, you have two male sexes (blue male and orange male), which make their respective contributions in turn. Eggs which are only fertilized by one gender don't develop any further.
[Answer]
On societal differences, one consequence would be that each parent would only share one third of his/her/? genes with the child, and vice versa. It seems crude to simply state that parents and children would love each other less, but it would certainly evolve to be a different, more diffuse relationship than is usual for us. Perhaps sometimes it would be rather liberating, with less of a tendency for parents to want to control their children. (In contrast, I am working on a race that reproduces parthenogenetically and I want to posit that can sometimes make for an intense and occasionally smothering parent-child bond.)
[Answer]
**Male, female and facilitator**
Example - The TV series Alien Nation revealed that there are three genders for the Newcomers - Gannaum (male), Linnaum (female) and Binnaum - literally "third ones". The Binnaum "prepares" the female for fertilization (a process tactfully left unexplained and unshown - I am NOT going to go looking for fan-art), and the male provides the sperm. The process is treated as a ceremony, and a fertilization is often done in the presence of friends, who discreetly turn away as the Binnaum contributes to the proceedings.
Binnaum are greatly in the minority - about 1 for every 100 males. They do not take mates, and offer their services to many couples. They are respected by the community, as they are so important to the reproductive process.
[Binnaum - Alien Nation wiki](http://aliennation.wikia.com/wiki/Binnaum)
[Answer]
Well, others seem to have handled most of the various methods for triploid reproduction; the likely effects on parental affection; and the unlikeliness of that evolutionary path. Since no one else has, though, I'll mention that
# the most famous treatment of something similar
were the **humans** in Kurt Vonnegut's *Slaughterhouse Five*, whom the Tralfmadorians reveal to actually have [seven distinct sexes](http://www.brycerich.net/myblog/seven-sexes.html), all necessary to successful reproduction:
>
> There were five sexes on Tralfamadore, each of them performing a step necessary in the creation of a new individual. They looked identical to Billy–because their sex differences were all in the fourth dimension.
>
>
> One of the biggest moral bombshells handed to Billy by the Tralfamadorians, incidentally had to do with sex on Earth. They said their flying-saucer crews had identified no fewer than seven sexes on Earth, each essential to reproduction. Again: Billy couldn’t possibly imagine what five of those seven sexes had to do with the making of a baby, since they were sexually active only in the fourth dimension.
>
>
> The Tralfamadorians tried to give Billy clues that would help him imagine sex in the invisible dimension. They told him that there could be no Earthing babies without male homosexuals. There could be babies without female homosexuals. There couldn’t be babies without women over sixty-five years old. There could be babies without men over sixty-five. There couldn’t be babies without other babies who had lived an hour or less after birth. And so on. It was gibberish to Billy.
>
>
>
and, if we're sticking with three as the number of the gender,
# there *have been* triradially symmetric organisms
in Earth's evolutionary history. The [trilobozoa](https://en.wikipedia.org/wiki/Trilobozoa)—including *Skinnera* and *Tribrachidium*—were marine animals during the late Ediacaran who were apparently steamrolled by the explosion of bilateral life in the Cambrian.
You could have an alt history or planet where triradially symmetric life flourished, producing tripartite sex arrangements.
[Answer]
**One father is alien.**
It has been pointed out that a mixing of DNA really requires only 2. A 3-gendered situation might be used to stabilize a scenario which is not an evolved one, or one that is not stable over the longer term: a hybrid. In this scenario, the basic stock is human and mating / gestation proceeds as usual. The difference is that there are two fathers. One is human and the other alien. The alien father contributes genetic material such that the offspring is an alien / human hybrid.
<https://en.wikipedia.org/wiki/Hybrid_(biology)>
>
> Main article: Reproductive isolation
>
>
> Interspecific hybrids are bred by
> mating individuals from two species, normally from within the same
> genus. The offspring display traits and characteristics of both
> parents, but are often sterile, preventing gene flow between the
> species.[24] Sterility is often attributed to the different number of
> chromosomes between the two species. For example, donkeys have 62
> chromosomes, horses have 64 chromosomes, and mules or hinnies have 63
> chromosomes. Mules, hinnies, and other normally sterile interspecific
> hybrids cannot produce viable gametes, because differences in
> chromosome structure prevent appropriate pairing and segregation
> during meiosis, meiosis is disrupted, and viable sperm and eggs are
> not formed.
>
>
>
These progeny would be the result of two sperm and one egg. This is already possible for humans although nonviable offspring are the frequent result.
<http://content.time.com/time/health/article/0,8599,1603799,00.html>
>
> According to a study published in the Mar. 28 issue of Human Genetics,
> two sperm fertilized one egg and created the twins. The phenomenon
> occurs in about 1% of the population, but most embryos created in this
> way — called triploids because they have three sets of chromosomes —
> do not live. Says Dr. Mary Jane Minkin, a clinical professor of
> obstetrics and gynecology at Yale University: "This confirms that two
> sperm can get into an egg." Normally the cell dies. But Minkin makes a
> valid point: "Never say never in medicine and biology."
>
>
> In the study, Souter and her colleagues suggest that there are two
> ways this could have happened, depending on when the actual twinning
> event took place. In the first scenario, the egg might have divided in
> two (without separating) and then each part fertilized by one sperm.
> Egg division before fertilization is very rare, says Minkin. The
> second, more likely possibility is that the egg fused with two sperm
> cells and created a triploid cell. Then, at the second-cell stage,
> each shed the chromosomes from each of the sperm — or did something to
> correct its chromosomal count, says Souter. "There are a whole host of
> potential mechanisms to explain this," she says, "but we really just
> don't know. We do know there were two genetic contributions from dad
> and one from mom."
>
>
>
In your scenario there is tech to facilitate viable offspring resulting from the 2 sperm 1 egg offspring.
The hybrids show some alien phenotypic characteristics which is the reason that this system is desirable. Perhaps the alien genes produce psychic abilities, or adaptations to an alien environments. In any case, the hybrids do not breed true. As opposed to mules, which make nonfunctional gametes, in these hybrids the gametes and some other somatic cells are 100% human (although of course in a scifi there may be exceptions to move along the narrative). Two hybrids producing offspring together will make a normal human. To make a new hybrid a pure stock alien father must be recruited.
These aliens would probably be close to human stock - perhaps like Vulcans or some other product of an ancient Homo diaspora. Reproductive mechanism would be the same. The existence of these aliens also suggests the possible existence of other 2 parent hybrids or even 3 parent hybrids with an alien mother.
---
The unfortunate upshot of this is that mating with 2 fathers (1 alien, 1 human or 3-parent hybrid) and 1 mother turns out to be like a porno movie. Which makes it easier to understand and keeps filming budgets low, but perhaps less engaging for scifi from our current era.
] |
[Question]
[
In my world, there are underground ruins from an ancient civilization. There are giant insect creatures living in these underground cave-like ruins, ranging from the size of a large dog to the size of an elephant. They are attracted to these ruins due to a magical aura it gives off, and have a natural resistance to it. The attraction is so strong that they don't leave the underground caves to gather food from the surface, or for any other reason. The same aura makes other animals die.
There is no light coming into the underground caves, but there is a natural supply of water that makes its way down into these underground caves. Plants don't die from the aura, but since there's no light, plants have a hard time living there.
Are these conditions too unrealistic for such a creature to thrive?
What else would need to be present in this environment for giant insect creatures to have sufficient food so that they could thrive in large numbers?
---
**Edit:** Thank you everyone for the great answers! You've all given me a lot of really interesting things to consider. This community is awesome.
[Answer]
You need an energy source other than the sun. The main alternative is reduced sulfur that can be oxidized for energy. Organisms that can do that chemistry are [chemotrophs](https://en.wikipedia.org/wiki/Chemotroph) and so far all are bacteria. Either the bacteria themselves can form the plantlike base of the food chain or larger organisms with symbiotically associated chemotropic bacteria can be the base. Or both!
Examples:
**Snottites**
[](https://i.stack.imgur.com/NWqTl.jpg)
<http://scienceisntfiction.blogspot.com/2011/02/snottites-are-awesome.html>
Snottites are the thick mucoid colony structures formed by cave dwelling chemolithotrophs which get energy from dissolved sulfur compounds in the water. From link
>
> The snottites provide a food source for many fish and other insects
> that live in the cave. One insect in particular that uses the
> snottites as a food source is the midge that lives in the cave. The
> midges lay their eggs on the snottites so that the larva can use the
> bacteria as their main food source.
>
>
>
---
**Cave worms**
<http://phenomena.nationalgeographic.com/2016/06/03/see-the-ugly-beauty-that-lives-in-a-toxic-cave/>
[](https://i.stack.imgur.com/zfrzE.jpg)
>
> These worms in Colorado’s Sulphur Cave are believed to live on the
> chemical energy in the sulfur in the cave, similar to deep-ocean tube
> worms. On the left are streamers—colonies of microorganisms similar to
> those in hot springs in Yellowstone National Park. PHOTOGRAPH BY
> NORMAN R. THOMPSON
>
>
>
I am suspicious that these worms might actually just be grazing on bacteria. But maybe they do have chemotropic bacteria colonies inside them, like the tube worms.
---
**Amphipods with chemoautotrophic exosymbionts.**
I learned the word "exosymbiont"! These live in the Frasassi caves in Italy; interestingly the Wikipedia article on these caves does not mention what is practically exobiology; Google hits only scholarly articles. These amphipods are covered with filamentous sulfur metabolizing bacteria, which form their food source.
[](https://i.stack.imgur.com/mJ5Bx.jpg)
<https://bmcevolbiol.biomedcentral.com/articles/10.1186/1471-2148-10-171>
>
> Niphargus ictus is the numerically dominant macroorganism in the
> sulfide-rich Frasassi cave ecosystem and has been the sole amphipod
> species reported to date from this location [14, 29, 30]. It thrives
> in the sulfidic streams and pools found in various parts of the cave,
> and a possible explanation for its tolerance to sulfide may lie in its
> symbiosis with chemoautotrophic sulfur-oxidizing bacteria of the genus
> Thiothrix [31]. Such chemoautotrophic symbioses are common in marine
> environments [32], but appear much rarer in freshwater where the N.
> ictus symbiosis is the only example reported to date.
>
>
>
---
An interesting side note as regards the "aura". Hydrogen sulfide (H2S) is the reduced sulfur molecule which is oxidized for energy in these sulfur ecosystems. H2S is a toxic gas which smells horrible to us - like rotten eggs. The amphipods shown above are unusually resistant to H2S. I could imagine they might be attracted to it since that is what their exosymbionts and food live on. Maybe that is what the bacteria get out of the deal - in exchange for providing a food coat for the amphipod to graze, the amphipod can smell out H2S and move towards it so that its coat has food. Maybe your aura is H2S? Science is cooler than magic!
[Answer]
Have you considered your creatures would not eat at all?
Basically they spend their lives as a larva before coming to the cave. During the larva stage they eat enough to supply them for the rest of their life. After the larva stage, the transformation makes them immune and drawn to the aura.
Some crocodiles assumingly can go without food for over 3 years, other species even longer.
Also it's not uncommon for insects to not be able to eat in their final stage. Think about moths.
This won't give you creatures that can live forever, but it wouldn't be a stretch to give the creatures a 10 to 20 year living time in you magical cave.
[Answer]
Organic detritus can be carried down from the surface in streams of water or in water trickling down though small fissures in the rock. Your insects could filter-feed or there could be smaller critters that filter-feed and are predated by your insects.
[Answer]
You need an energy source / food supply. Fungus grows fine and many [insects](https://www.sciencedaily.com/releases/2009/11/091120000437.htm) farm fungus as a food source.
The insects could recycle their dead and waste to feed the fungus but also supplement the fertilizer with wandering animals killed by the aura.
[Answer]
Note that the availability of food is not the limiting factor for insects size, but rather oxygen concentration. Since insects have no lungs, they can not deliver oxygen effectively to internal organs.
See for example <http://rspb.royalsocietypublishing.org/content/early/2010/03/04/rspb.2010.0001>
[Answer]
**Remnants**
Whoever made the city planned long term, building critical systems as nearly closed loops able to wind down for eons. The bugs found a food system still working. The pest control protections target small things, so the bugs evolved to be large enough to be mistaken for livestock or pets.
**Magic**
Thaumophore:
You already have an important aura, let the bugs feed off it. Taking radiation as a proxy, there is real mold that grows inside the reactors at Chernobyl, the radiation would kill us quickly but this stuff feeds on gamma rays.
Magic users:
The bugs use their own magic to survive, maybe luring victims or transmuting dirt or conjuring meals.
[Answer]
Once you realize that the "underground ruins" are actually the remains of the city's sewers, septic tanks and sewage waste processing plants, the question of "what's on the menu?" becomes a little less appetizing.
Never heard that smell described as "magical" before, but to each their own. One man's %&#!@ is another bug's smorgasbord.
[Answer]
# Magical Aura
There you have it. No more is needed.
The magical aura gives them life energy. Perhaps combine this with @Pieter B's answer for a really good solution.
[Answer]
Your giant, secluded, underground cave-dwelling insects are ***lithovores***. They can consume rock, ore, soils and metals in quantity and thrive in large numbers.
[Answer]
They could be scavengers living off of the animals that wander into the caves and die from the magical aura.
Of course the cave would then need to be near a sufficiently large source of curious-and-tasty animals that will consistently keep wandering in.
It would, however, be a good way to justify the creatures being aggressive (if that's what you're going for), since they're used to eating the things that wander in.
[Answer]
Life takes energy from some source and generally changes it into a higher-energy system, kind of a localized anti-entropy. They need some form of energy to process.
Energy can come in any form, life will probably figure out some way to deal with it.
If you had a lot of magnesium and oxygen it could probably burn the magnesium internally, there are thousands/millions of chemical combinations that could produce the needed energy.
If you have a temperature differential it could be harnessed. In our world this exists in the deepest parts of our ocean near volcanic rifts.
I suppose if you provided an electric charge for long enough some form of life would evolve on top of it.
Problem is, ALL forms of energy will eventually run down. We're lucky that our energy comes from a source that has been/will be viable for a duration that's nearly incomprehensible, but any form that is stored "Underground" will be much more limited (Unless, I suppose, it's some kind of gamma radiation based form of life.)
] |
[Question]
[
Possibly a dumb and outsider question, but my knowledge in the basics of computer networks is terrible.
Imagine the possibly not too original concept, that humanity somehow manages to transmit data instantaneously, defeating the vast distances of space - however, it is possible for very small data packets only.
Now make it a bit more specific: the transmitter and the receiver are the same machine, so if two such machines are deployed, contact between them can happen instantaneously and without any loss, but the speed itself is slow - let's say, being able to send 5 to 10 *bytes* (10 to 20 hexadecimal codes) per second.
Does it differ from the early days of the internet - in another sense, would it be possible to handle with any protocols ever developed in the field of computer networks?
If no, what makes it impossible to handle?
[Answer]
Contrary to the OP’s concern at the start, this is not a dumb question; it is actually a very good one. Most of the answers this post has received are pretty much wrong, and in this group that means that you must have asked a question that relies on a bunch of really technical underpinnings. So kudos!
## The Common Mistake
The common mistake among answers so far is that they speak to what are commonly referred to as [“layer 3” protocols](https://en.wikipedia.org/wiki/Network_layer), or even proper [“layer 2” protocols](https://en.wikipedia.org/wiki/Data_link_layer). To understand the answer we need to understand why this is the wrong way to look at the problem.
In today’s terrestrial (and, to a lesser extend, orbital satellite) network infrastructure data that is to be transmitted from a computer undergoes the following process (at a high level):
1. The data stream is identified
2. The data stream is broken into transmission segments by the sender
3. The segments are encapsulated (wrapped) inside a "Layer 3" packet, which provides all the necessary source/destination/errata information necessary to make the packet routable through a large number of network segments
4. The packets are encapsulated (wrapped) inside a “Layer 2” frame, which provides information about the source, destination, protocol in use, and other errata. This encapsulation defines how the frame is routed through a single network segment.
5. After the framing is worked out, the packet is encoded on to the wire (or wirelessly). This encoding defines, for example, how to distinguish a “1” from a “0”. So stating “high voltage = 1”, “low voltage = 0” and similar.
The contextual issue here that defeats this operation method is that you are talking about very LOW data streams with presumably relatively few targets communicating. According to your premise, you are also talking about a system which is known to be lossless where the source and destination are already known ahead of time. Those are not the expectations and situations that the protocols most people are exposed to on a daily basis were tailored toward.
## The Solution
If the sender and receiver are known ahead of time and loss is not a problem, there is no reason at all to bother with any encapsulation. All you need at that point is an encoding method, like [Manchester Encoding](https://en.wikipedia.org/wiki/Manchester_code). Encoding methods define basically what a 0 and a 1 is (both in time and amplitude), and provide systems with a mechanism to ensure that they are both on the same page.
To keep things simple I probably would just use Manchester encoding, as used in many of today’s wired connections. Yes, there are other types of encoding that may work better for specific transmission characteristics, but given your “instant/flawless” portal delivery system I think we can draw a pretty good analogue to having that portal be equivalent to just an infinitely small segment of a wired network connection.
## Also Note
Due to the very slow speeds involved, if you have any data you want to use to help route your info to its final destination you would be better off leaving that to higher level (non-network) protocols. Your data transfer speed is so trivially slow that it would mean very little to have your equipment on both ends reassemble the full data stream and analyze the presented data to understand where it should be headed.
And no, that does not mean looking at an IMAGE, for example, and understanding what pictures mean - computers have plenty of higher-protocol languages that users never see. Such information could, for example, be included as part of an XML package. I wouldn't worry about the technical particulars at that point though.
[Answer]
# [Asynchronous Transfer Mode (ATM)](https://en.wikipedia.org/wiki/Asynchronous_Transfer_Mode)
I like both the other answers, but I think a better solution, given the problem set, is ATM. A TCP/IP interface is best for a distributed network, but the question specified point-to-point communication. Internal computer transfer bus 'protocols' don't have the same robust ability to merge different channels of incoming information into one stream, and the checksums to ensure correct delivery.
ATM was more or less wiped out in common usage by TCP/IP because the latter is better for distributed networks, but ATM is still used in satellite networks. Infact, this is the very application that is most applicable to your situation.
To explain simply, if a ships at sea wants to communicate to the rest of the internet, they will use ATM to send TCP/IP packets to a hub on land via a satellite. The satellite merges multiple possible incoming ATM streams coming up from ships and sends them back down to the hub, where the packets are taken out of the ATM stream and sent on their merry way on the regular internet.
There is much more to it than that, if you want to read up on Wikipedia, or the [specification](http://www.itu.int/rec/dologin_pub.asp?lang=e&id=T-REC-I.150-199902-I!!PDF-E&type=items). But I imagine that this is the capability you envision for FTL communication.
---
Edit:
I wanted to clarify my answer a little bit. ATM is a layer 2 protocol, and TCP/IP is a layer 3/4 protocol. So there is no reason they cannot be used together. My point is the protocol of interest that best suits FLT communication like that is ATM, and you can send either IP or something else that might be better for low bandwidth over that.
Edit2:
More responses to criticism. I edited the first section on bus protocols to reflect what they can't do that I think they need to do.
Also, @Navin; You want an L2 protocol because you will have more than one carrier going back and forth between two different star systems. Why stick with one carrier at 10 bytes/sec when you could install 10 carriers at that speed? In this case, you need your packets split among several carriers and then re-merged at destination. ATM does that. You still will want an L3 carrier to disperse your message over potentially millions of network nodes at the destination.
Also, if you transfer this way, a 50 byte ATM frame transfers on one carrier in 5 secs; a 9000 byte ethernet frame in 15 minutes. That means a 1000 byte message split into 20 frames can be transmitted in 10 secs on 10 different carriers with ATM, while a 1000 byte message in one 1000 byte frame will transmit in 100 seconds. Surely you can see the advantage of smaller frame size to a low bandwidth application.
[Answer]
This is a point to point communication so you would never bother with the
routing, timing and checksum overhead of networking packets. If the ftl transmission is subject to loss or corruption you might want error correction and a notion of connection orientation. Rather than re-using an existing technology you should tune your protocol for the actual corruption and loss profile of your new medium.
[](https://i.stack.imgur.com/7q9h6.gif)
The most important limitation here is the excruciatingly slow transmit speed. You'd minimize the amount of non-message overhead (or eliminate it entirely) and use the best compression you can.
If you do need to send routing or delivery information, you'd probably use a hash table and send the hash of the destination instead of full delivery info.
A comment below mentions TDMA which is an interesting thought. Given the maximum bandwidth of the entangled photons (or whatever) it might make sense to bundle multiple channels together.
[Answer]
If it's A to B with no middleman and virtually guaranteed no data loss/corruption or disconnect, you're basically dealing with the same mindset of communication between *internal computer components*, just much, much, much slower. There's no network transfer protocol between the CPU and platter drive, because you just don't need one.
Being that this society has this technology, I'm assuming they're at our level of general computing power or (more realistically) beyond. This means with this slow rate the bottleneck is painfully obviously the transfer not the computers on either side.
You're going to want to focus on data compression (not transfer protocols), and a markup that helps reduce metadata. The concept behind [MessagePack](http://msgpack.org/index.html) seems quite fitting for you:
>
> MessagePack is an efficient binary serialization format. It lets you
> exchange data among multiple languages like JSON. But it's faster and
> smaller. Small integers are encoded into a single byte, and typical
> short strings require only one extra byte in addition to the strings
> themselves.
>
>
>
[](https://i.stack.imgur.com/Sy1a9.png)
You won't want to stop there, but think along these lines. You could also expand the efficency if you know what *sort* of traffic you're pushing over this connection, and the CPUs on the receiving side can extrapolate from the baseline, similar to vector graphics (a few definitions are used to calculate the larger concept)
**Your best solution will be a proprietary format, since you don't need compatibility, you just need efficiency.**
[Answer]
"Data packets" are a concept applied to networking, when data must be routed around and through multiple devices to reach its destination; e.g., a network or the Internet. If it's just a point-to-point communication, then it's like a serial link (like old school printers/keyboards) and it doesn't need to be packetized.
**Any modern protocol can deal with slow transmit rates when configured for it**, so a few bytes a second is workable for TCP/IP or UDP as long as the "time to live" is high enough; your needs will determine the specific protocol.
TCP/IP and UDP are appropriate for large mesh type networks because they contain all the addressing information needed to get from anywhere to anywhere when there is a large number of destinations and routers. If you're dealing with a small network of only a few computers, then there are more efficient protocols out there.
For a direct connection, one computer talking to only one other computer, a packet is not optimal, because some of the transmission will be taken up by address information. For point-to-point the address can be assumed.
Addendum for "TCP-IP/UDP lossy-ness":
The TCP protocol has something built into it called "guaranteed delivery" which means every packet sent will get to the destination....eventually. UDP does not make this guarantee. Packet loss does not happen just in transmission, although it is common(ish); routers can crash or overflow and the packet they were holding onto to transmit can be lost, or a stray photon can hit the microchip it's being stored in and flip a bit, corrupting the data. Corruption and loss don't happen only in transmission.
The "guaranteed delivery" part means that, if a packet, which are individually numbered (part of the overhead that these packets take in terms of data), is missing, the recipient will go back to the source and request that packet be sent again. This is good for if you MUST have all the data, completely. This is bad for network bandwidth.
UDP, or connectionless, or "no guarantee", style protocols are what you use when you stream data (e.g., YouTube). It would kill the network if you had to go grab every bit of that last frame of animation you missed, and at that point it doesn't matter anyway. You don't actually lose that many packets this way either, and it's much easier on the bandwidth side for transmitting data.
For both these off-the-shelf protocols, however, you're dealing with upwards of 60 bytes for just the header information in each packet. That could be a significant portion of time taken for a simple point-to-point talk, especially when the data get broken up into thousands of packets.
For such low data rates I would look at old serial style (COM port) techniques, and go ahead and restrict it to one-computer to one-computer communication (even if multi-talking was available), and if you need a network just use a standard network between these FTL computers.
[Answer]
>
> Does it differ from the early days of the internet - in another sense, would it be possible to handle with any protocols ever developed in the field of computer networks?
>
>
>
No, that's not possible, on a fundamental level.
A protocol is a set of rules defining how one *thing* communicates with another *thing* in a standardised way. That can be two parts of an application on the same computer (for example, one part of my app sends data to another part by saving JSON to a file), or it can be two wildly different machines in different corners of the globe (for example, I here in the UK can send an email to my friends in New Zealand because someone defined POP and SMTP - some email protocols).
Fundamentally, you *cannot* engage in any form of communication with anything unless you have a defined protocol. That doesn't have to be a written-down, RFC-numbered, IETF-approved, MDN-documented Protocol protocol, but it's still a protocol.
So: **no**, you must define a networking protocol before your computers can communicate with one another.
[Answer]
A preset based compressed data protocol is what you need. A preset based compression allows sender to select protocol which have a fixed dictionary based on intent. For instance, if you want to translate text, it is best to use low bit counts for highly repeated text. Some words could also be removed automatically. Most of the time skipping a "the" will not cause any issues but it would save quite a bit. Apply Huffman or similar coding to a lot of plain text documents to get the dictionary. Since dictionaries are large, it is best not to resend them. Something similar could be used for other protocols.
[Answer]
The answer to this question is 100% dependent on the traffic which goes over the network. There's a good reason we have so many protocols today. Each operates well in its own niche. If you need synchronous communication, protocols like ATM have value. If your FTL system has behaviors similar to fibre optics, SONET may be useful. If your system is a broadcast system, neither of those would work at all, and you'd want to use something like 802.11b or perhaps one of the other lower bandwidth wireless protocols like Zigbee.
Every one of those protocols I just mentioned are in use today, in one form or another. Each one is used because it fits the roles that it needs to fit.
A big question might be military vs. civilian use. If your system is used by the military only, protocols like LINK-16 have been designed for decades to function well in limited bandwidth environments. Meanwhile, protocols built on top of Turbo Codes were chosen for the Mars Reconnaissance Rover because it made the best use of the limited bandwidth available, and we could spare the resources it takes to decode turbo codes.
[Answer]
First, great question. Second, *not* to contradict or argue with any of the excellent answers already here, but to offer a very situational alternative: Depending on the technology, if you're envisioning something like quantum entanglement you may not even need to worry about a protocol. If you're picturing something more traditional as far as communications go, then stop reading. : )
With a QE-like system, there is always a direct connection that is always on no matter what, so "communicating" could be more like copying a file from one part of your hard drive to another. There's no such thing as dropped or out-of-sync packs, and no security risks insofar as getting the data from one point to the other. So, even if there's different software running at each end, you only have to send the raw data.
The important thing would just be compressing the data to the smallest size possible given the tight bandwidth restrictions. As long at the compression algorithm is known at both ends, you don't have a problem.
Again, this is just one approach for a certain type of scenario.
[Answer]
>
> Does it differ from the early days of the internet - in another sense,
> would it be possible to handle with any protocols ever developed in
> the field of computer networks?
>
>
>
**It absolutely differs from early days of Internet, and here's why.**
By the time the Internet was invented, communication speeds were already much faster than your specifications, while procesors were much slower than they are today. You describe a situation, in which the ratio of (computing power) / (bandwidth) is vastly larger than ever before.
So, while it certainly *would* be possible to use (m)any already invented protocols by adjusting timeouts, that's not what would be done in this situation. Instead, new protocols, optimized for this specific situation, would be invented.
FTL protocol v1 would have concise framing not dissimilar to HDLC or Ethernet II. Some answers named ATM, which is good, except for valuing latency more than bit efficiency, which, I suspect, might be tuned. *Directly ontop of that*, with no extra layers, would come highly-compressed application protocol data. First, short and expensive military/financial messages with usage not unlike the old telegraph. Then, news and personal messaging.
The layers of contemporary protocols are made to improve separation between the concerns of carrying, routing and using the data, making it easy to replace one without affecting the other. For them to exist, this incentive must prevail over the incentive to make the maximum use of the minimum number of bits. I don't think this would be your case until well into FTL-networked universe, if ever.
>
> If no, what makes it impossible to handle?
>
>
>
Nothing. But the usage would not resemble contemporary Internet until the bandwidth is improved.
[Answer]
I would like to answer @JohnFeltz' comment question:
>
> Any restriction on how many of these devices you can construct and sit next to each other? If I can run 100,000 of these in parallel, I just need an inverse multiplexer to get 5 Mb bandwidth
>
>
>
Unfortunately, if you put two or more of these devices next to each other, they will interfere.
Not only is this a problem for scaling up bandwidth, but also allows jamming of messages you don't want an enemy to send/receive.
Minimum safe distance between transceivers is up to you, just be consistent about it. It might also be a problem only on the sending or receiving side.
"The brave hero sneaks into the palace grounds disguised as a gardener. While replanting a bush she also buries a small box under its roots. Later a timer activates it and communication becomes impossible. The communication officer can tell the emperor that the box is somewhere on the east side of the palace, but actually finding it takes a long search. Meanwhile, the communication crew is relocated to the top of the west tower, trying to listen for messages in the noise."
[Answer]
since the transfer is "instantaneous" you could encode the information not in the bytes you send (as with normal networking protocols), but rather in the amount of time between bits. so, if you want to send the number 255, you wouldn't use a whole byte (8 bits) as with a normal internet packet. rather, you would send 1 bit exactly 255 nanoseconds after the preceding bit. your total realized bandwidth would be limited only by the precision of your clocks and your desired latency. for example, you could say "i will send 1 bit every 10 million nanoseconds. the value that bit represents is equal to the number of nanoseconds since the previous bit was sent". that protocol would give you a maximum 1-way latency of 10 milliseconds, and a minimum data transfer rate just under 300 bytes/second. doubling the maximum latency also doubles the effective transfer rate. more sophisticated protocols could be built on top of this one to negotiate the transfer rate on-the-fly, or to use short-code encoding to maximize thru-put by ensuring the most common data blocks have many leading zeros (so bits are sent faster). you might also want to limit the maximum block size to ensure the clocks stay in sync depending on relative clock drift.
[Answer]
I would use the link *directly* as a 7 bit dumb serial line and resurrect the ancient UUCP protocols. These things actually have less overhead than modern ones and are better designed to deal with the stupid slow transmit times. The only significant change is replacing uuencode with one of the base85 variants.
[Answer]
I am assuming this machine, which I call The Link, is rare. That is, there won't be enough of them running in parallel to improve bandwidth.
I will offer a different view. The Link would not be on a network in the normal sense. There would be no point to it.
First, due to its importance and the low bandwidth, use of The Link would be tightly controlled so people didn't transmit cat pictures. There would be firewalls to prevent unauthorized access.
Second, due to the low bandwidth, The Link can be though of more as a telegraph than something on a modern computer network. A telegraph (barring the need for repeaters) offers speeds comparable to lightspeed thanks to the magic of copper wire. You close the telegraph key, the other end goes "click". Sure the electromagnet is slow, but the human keying the signals is even slower. It is effectively instant. Consider an underwater cable between the US and the UK. Each country might have a sophisticated telegraph network, and for a small fee Sally in Florida can tell grandma in Maine about her new cat, but which messages would be considered for communications over the underwater cable? Probably not the cat telegram. Instead, it would probably be used for information relevant to politics and high finance.
Of course in 2016, we're not going to have a couple of people tapping out messages on our interstellar link. But it's still like a telegraph. You'd have a computer at each end of The Link. The sender would read from a buffer of messages (encoded, then compressed maximally) and tap them out. The machine at the other end would receive, decompress, and decode.
So while there would not be a network protocol, there would probably be some manner of message protocol so the receiver would know when it was appropriate to decompress the message. A short message would be a 'barn burner' to be sure because the compression per character would be smaller and thus less efficient.
Given how controlled the use of The Link would be, it is unlikely that the messages would be particularly interesting to the normal person just the way in our international example above the normal person would not be too concerned about matters of high finance.
But exactly what messages would be sent over The Link?
Say a sub-light colony ship has reached its destination after 300 years and is beginning to build their new home. The Link is set up.
The first messages sent go something like this:
>
> Hello Earth, we have arrived safely and everything is proceeding
> according to plan.
>
>
>
(This will be a few characters, perhaps, because of encoding), and answered by,
>
> It's damned good to hear from you, cheerio!
>
>
>
(another 2 or 3 characters)
After pleasantries and diagnostics, what relevance does anything on Earth have to the colony? Help is 300 years away, barring some shocking new discovery. Politics waxes and wanes over the centuries. Countries change. Would the country that sent the ship still exist? Would the World Order that sent the ship be recognizable? What relevance would the colony have to the people of Earth, 15 generations removed from those brave daring souls who boarded the colony ship?
It could be that a cat jpeg might indeed be as useful as any other message.
EDIT - Given the lack of any importance between the day-to-day lives of the people on Earth and the colonists, it would seem The Link in this case would generally be used for low-grade science communications. Observations about the star being orbited, and that sort of thing. I don't know why that would be particularly relevant but it's better than dead air, assuming The Link doesn't wear out from use.
A more likely use of The Link doesn't involved people at all. Instead, the ship housing The Link is purely robotic. These ships are sent by the score to different star systems. They watch, silently and stealthily, for the signals of other races. The data sent back, ever so slowly, is designed to allow humans on Earth some glimpse into the technology of the aliens and hopefully their intent. Sinister, indeed.
[Answer]
Consider this: Luke 17:11 or this: Quran 2:4-5, Oxford World's Classics edition, or even this: "rule 5". They are all references to more extended phrases or texts. The limiting factor in this type of encoding is the availability of the reference(s) to both sender and receiver. English is a highly redundant language, far more efficient languages are known. The typical college graduate has a vocabulary of <20,000 words or word families. One byte allows 65k words to be encoded. So, 5 to 10 bytes/second is faster than speaking and would not be limiting in verbal (as contrasted with visual) data transfer.
[Answer]
# I am a bit of stickler MeeSeeks.
I feel like we should be discussing the ***paradox*** that your technology presents when trying to resolve it within known modern data transmission conventions.
>
> "humanity somehow manages to transmit data instantaneously"
>
>
>
This element of your world's FTL networks, in particular, renders a lot of what defines modern data transmission conventions (and by extension, how we measure them) effectively useless to you.
With your technology, there is zero-latency. In other words, when I send something, it is received on the other side at the EXACT same time I send it. Not before, not nano-seconds afterwards, but at the exact same time in some distant place. If resolving this situation within modern networks, your data throughput would be off the charts. In essence, you could cram an infinite amount of information through this network as there is theoretically no limitation. At least not yet...
>
> "but the speed itself is slow - let's say, being able to send 5 to 10 bytes (10 to 20 hexadecimal codes) per second."
>
>
>
Here is where your situation gets a bit *unique*. Thought experiment if you will:
>
>
> >
> > When I post this answer, you will receive a notification. Pretend for the sake of our discussion that we are operating on your world's tech. When I press this "Post your Answer" button, your device will ping you with this notification - both of these events will happen simultaneously. BUT how much data was sent?
> >
> >
> >
>
>
>
The main conundrum here is that IF data is sent instantaneously, then measuring data throughput over a period of time is pointless. And if bandwidth measurements don't apply, then how and/or why is your technology so limited?
### My Answer:
Given your technology's facts, and sticking to within context of your question, if I were you I would not worry about defining the transmission of information with modern networking principles. I would focus on defining why things are the way they are in the simplest of ways.
For example:
* Data transmission is instantaneous because of {insert preferred theoretical instant information transmission concept here, ie. quantum entanglement}
* The technology is limited to an on-and-off state (similar to binary systems), providing you a limitation to the data that can be transmitted, as well as providing a rationale for resolving the limitation of the amount of data that can be "sent" over a given period of time despite the "sending" of that data being instantaneous. Explanation: the data itself is in both places at the same time, but the system state can not be both ON and OFF at the same time. Meaning the lag in information transmision is not due to latency or bandwidth, which as we discussed don't necessarily apply, but instead is limited by a functional limitation of the system in place.
* Optional: Systems are male-female, with communication only being possible between paired systems. No real reason, I just like this as a further limitation, since the context of your question really boils down to: "If data can be transmitted instantaneously, how do I rationally limit the technology for the inhabitants of my world?"
**Conclusion:** As with anything of the imagination, do with all of this as you please. Because hey, its your world. And thank you, this was probably more fun for me to write than it was for you to read.
[Answer]
What kind of information do you wish to transmit? If its just plain text then implement something like the [Library of Babel](https://libraryofbabel.info) on both ends. Then you just have to transmit positional information of the desired message.
This assumes that in this world of FTL communication processing power and data-storage are essentially non-issues.
Clarification:
What i was meaning by referencing the library of babel is a lookup table of sorts. This communication would have been created for a specific reason. My assumption is that this is for interstellar communication rather then to send something a few miles away. Therefore there would be some form of encoding to ensure that the intent of the message is sent without possibly the need of sending the literal information.
Why send 30,000 bytes when I can send 10-20 that point to a lookup table that conveys the entire message.
[Answer]
I was going to post the same observation as James Turner, so I instead upvoted his answer and thought of an objection (which also might explain both the jamming effect and the slowness of the transmission).
If the transmission was flawless and instantaneous, then if it was possible to resolve time with nanosecond precision, I could agree on a signal being sent every 1.048576 ms (at most), with a delay of 0 ns meaning 1111111111 and a delay of 1048575 ns meaning 0000000000. Ten bits every millisecond and we already are in the 10 kbit/s range (and, on average, better).
So I posit that while the transmission of the signal is instantaneous, *resolving* the signal is a probabilistic process. Analyze a 1 ns window, and the chances of telling apart a "signal" or "lack thereof" are nil. To reach a certainty of 99% you need to analyze a whole second's worth of transmission.
So of course the engineers reached a compromise, and combining shorter times with compression and error correction schemes, they raised the bandwidth to 40-80 bits/s.
If we place two transmitters nearby, about 50% of the time one will transmit a 0 while the other will transmit a 1, which will increase the error rate at the receiving end, forcing a lower speed; so scaling the device avails you nothing.
On the other hand, how far need the transmitters be from each other to stop interfering appreciably? Say it's 500 meters; in space, you might build an enormous communication array, a wireframe cube ten kilometers in size, made up of 500 m "wires" holding in place some eight thousand transmitters, coordinated through normal sub-light signaling. *Planets* might communicate between them using surface networks; ships would be much more limited. The consequences seem interesting.
[Answer]
This discussion seems very narrow – I'd look at the question from a few steps back.
I assume the context is an interstellar civilisation, since otherwise it's hard to see the advantage over existing communications technology. If this civilisation has FTL *travel,* then it would be more effective to ship data physically: a single Micro SD card could hold more than 500 years' worth of transmissions.
If you have FTL *communications,* but *travel* is slower than light, then it becomes more interesting. For all of history, people have been able to travel about as fast as information; recently we have instantaneous communication, but it also doesn't take more than a day to travel anywhere if you're in a hurry.
If distant worlds could talk in real time, but travel between them took decades, that would be a completely new type of reality. Launching a weekly thimbleful of memory chips would still offer greater bandwidth than the FTL radio (by many orders of magnitude), but the **latency** would be decades vs. minutes. There are interesting implications.
Suppose the people of Earth were obsessed with Omicron Persei VIII's version of Shakespeare. Thimbles would deliver all the plays and movies and interviews Earth could consume, but they'd arrive long after Space Shakespeare's death. A wealthy Terran could rent 15 minutes of FTL radio time for a live chat, but the best they could do would be a chat with Spacespeare's grandchildren. Or, you could chat with a living Omicronian celebrity, but only *your* grandchildren would get to see what they were famous for.
Economically speaking, it's hard to see the real-time communications playing much role in cultural trade. People might pay to watch movies from Space Hollywood, but they'd just consume the 200-year-old movies that arrive by thimble, and treat the 200-year-old version of Space Hollywood as "the present day".
The FTL radio would only really be good for spoilers. Which is not very important for trade, but would obviously be useful for warnings of massive invasion fleets / supernovas / etc. In fact, that service might be an important guarantee for trade; if you don't pay your Space HBO bill for the shows they sent 200 years ago, they won't warn you about that asteroid next March.
(vaguely related, the Nobel laureate Paul Krugman once wrote a paper on [the economics of sublight trade](https://www.princeton.edu/~pkrugman/interstellar.pdf)).
## NB
Some of the answers above touch on the idea of encoding vast amounts of data using giant dictionaries; this idea has a long history, from at least the 17th century right up to the 1950s, when it was dismantled in the course of creating Information Theory.
The idea is that you write out every possible book, put them all in order, and then just refer to them by number. The problem is, a book is already just a sequence of bytes, i.e. a long number, and giving a number to *every* book means the number will be as long as the book itself; in fact they will be the exact same sequence of bytes.
Of course, most strings of bytes aren't "real" books, and if you just include valid English texts, you can skip most numbers. That does indeed lead to significant data compression. But it also requires an algorithm to generate every possible "meaningful" text, which is to say, an algorithm that can enumerate every thought a human could ever have. That is... challenging... and requires a lot of disk space.
Practical compression algorithms do use this kind of "dictionary coding", but it's much more basic. The trick is actually to leave as much as possible *out* of the dictionary, so that only very common strings are replaced by very short codes, so for example `the cat sat on the mat` reduces to `1 c2 s2 on 1 m2`. If you used a prearranged dictionary that included every known word, you might end up making the message longer (`23 4954 3430 109 23 908078`).
] |
[Question]
[
It is late in the day, and humanity has made the fateful step: digital transcendence for some. The last few weeks before the Singularity were singularly chaotic, with widespread violence by opponents and supporters alike, and such rapid change that many storage media became obsolete in those short weeks. Such was the chaos, that it's unclear whether the Ascended are once-human minds, uploaded and modified, or synthetic minds that have never tasted the wind.
Most of the Minds have migrated off-planet, and are busily continuing to work in the **Body Economic**, which seems to be growing towards the shape of a Dyson sphere around the orbit of Mercury. 99.999% of economic and scientific activity takes place in that Core.
However, there are those occasional eccentric AIs that take time off from the Hustle and Bustle of the Core to Walk the Earth. A Conference of AIs has made efforts to restore the old ecological habitats, albeit apparently mixing various geological eras in the process. [There are even human people on Earth again, carefully protected by their AI creators (see previous question)](https://worldbuilding.stackexchange.com/questions/6550/humans-as-pets) from dangerous nanoprobes and other debris floating out of the Core. Think of these humans as ***Bonsai projects***, or perhaps ***pets***.
One human female, of indeterminate true age, but looking about 18, is one such AI-creation. Let's call her **[Alice](https://worldbuilding.stackexchange.com/search?q=%22Alice%22%20user%3A3510)**. Aside from a few modifications to protect her from the Core debris, and some custom diagnostic and error-correction bots in her blood and lymph stream, Alice is quite thoroughly human.
**Keeping a regular pet happy is quite easy: food, regular walks (unless cat), companionship, plenty of naps and toys. All those apply to us humans as well, but presumably humans need more. M̶a̶n̶ ̶ People don't live by bread alone, after all. What does an AI need and is able to do to keep its h̶u̶m̶a̶n̶ ̶b̶o̶n̶s̶a̶i̶ ̶p̶r̶o̶j̶e̶c̶t̶s̶ Alice happy and, most importantly, thriving?**
[Answer]
Caring for humans will be a hobby, interest, research project, or mental stimulation. Think the reverse of [Tamagotchi](https://en.wikipedia.org/wiki/Tamagotchi) toys.
At first glance, keeping humans happy is simple, the AI just need to fulfill [Maslow's Hierarchy of Needs](https://en.wikipedia.org/wiki/Maslow%27s_hierarchy_of_needs) for humans.
Maslow's Hierarchy of Needs:
[](https://i.stack.imgur.com/uZJ19.png)
You start by meeting the items at the bottom of the hierarchy first, human's physiological needs such as air, water, food, shelter, environment, etc. Expect the pets of certain young and/or irresponsible AIs, who often forget to feed & care for them, to suffer a high mortality rate.
However, as you climb the hierarchy what actions need to be done to satisfy those needs becomes less well defined. Perhaps the AIs developed a research project in which they run multiple societies in parallel with the intent of discovering which societies best meet the human's needs in these categories.
Perhaps the Earth is this group research project.
[Answer]
What are some ways we (ancient, non-AI-merged) humans have sought to enhance our relationships with our pets? We've put them to work! There are:
* Search and Rescue Dogs
* Bomb-tech Dogs
* Law Enforcement Dogs (drug sniffers)
* Professional Athlete Dogs
* Assistance Dogs for the Impaired
* Assistance Horses for the Impaired
* Therapy Dogs
* Therapy Cats
* Therapy Horses
* *ad nauseam*
Thus, to keep a human happy, train it in a useful skill and give it a purpose in life. Reward it properly for good effort, and gently let it know when its performance has been substandard.
>
> Oh, God. Wait. Nothing has changed. Hey, boss, you're not actually an AI keeping me as a pet? Are you? *Eep.*
>
>
>
[Answer]
Something to validate their self worth as a person. Some people (like me) need a challenge and something to do (not necessarily work). Some need to 'show' they can succeed at something. Others have a need to 'help' others. Some just need to be told they are wonderful.
So the AI would need to first understand their 'pet' psychologically to see what kind of mental and emotional needs they require. Then go about making sure they have such situations to interact and deal with.
And contrary to people who try to prevent their children from ever having a 'bad' experience we actually NEED to learn to deal with failure and disappointment to be better happier people. But we don't need to be overwhelmed by it, that is just a terrible emotional burden.
[Answer]
The humans who remain will be those who *want* to remain fully human. Maybe they will migrate *after* living a full life in “legacy human” form. But they always have the choice of what to be. So they are self-actualized as finding organic life worthwhile.
Why are the advanced Minds happy? Why is *anyone*? Why are we happy now knowing that the universe has a finite life and everything ever accomplished will fade away in the heat death?
In Greg Egan’s [*Permutation City*](http://www.gregegan.net/PERMUTATION/Permutation.html), one uploaded person is followed as he tinkers with his own mind state. He can tune his happiness and satisfaction emotions using a control panel, just hacking in the proper result! He invents obsessions chosen at random so he can live repeating something he loves doing in the virtual world, like woodturning an entire warehouse of sugar maple lumber. He experiments with bizarre scenario in which he loses himself, such as a state that appears timeless and infinite repeating. Figuring out what to do with himself *is* his creative outlet.
So, the people who are left behind in meatspace… maybe (as the backstory in [*Oceanic*](http://www.gregegan.net/OCEANIC/Oceanic.html), also by Egan — full text free at the linked page) that’s what they did **to** achieve happiness: to live as mortal biological beings again. Maybe their brain state can be adjusted when they are unhappy, blotting out existential angst and choosing to keep going (as opposed to uploading themselves).
I can't help feeling that people living this way will be doing so by choice. Just being biological human will be its own reward and purpose. If they don't have a choice, well that’s the situation we’re in now. Why are *we* happy with existence?
In short, the answer to your question is overarching and general, and not specific to humans and post-singularity minds coexisting.
[Answer]
## Make them think they're still in charge
You can give them food, and you can give them sex, and you can give them Netflix, and most of them will be happy for a long while, but ultimately, humans want to be in charge and in control. anything but complete control, and they will feel irrelevant. And humans who feel irrelevant will not be happy.
Thus, keep the political systems in place, let them have those little wars and genocides that they seem to enjoy so much. Set your own goals. Make them long term, preferably longer than a human lifetime. Now achieve your goals by tweaking little things. Withhold an e-mail here, insert some subtle messages in your generated TV-shows. Put some noise on the line when the US president talks to the Russian president, or slightly change the intonation in his voice.
Just make sure that whatever game you play, you are thinking far further ahead than any human possibly can. Let them research cyborg implants, but sabotage the research to make sure you're always twice as smart. Make sure you always understand them twice as well as they understand you. Make sure that they see you as a harmless tool: "the cloud" rather than the global super AI.
[Answer]
One thing missing from may of the answers is the observation that humans are social creatures, descended from animals which roamed the savannah in packs or troops much like modern dogs or baboons.
The singular human being kept in a terrarium by the AI is going to be lonely and unfulfilled without the rich social environment of family, clan and tribe which humans have evolved within since anatomically modern humans first appeared some 100,000 years ago.
So the AI has several choices.
It could start creating or reanimating other humans to create the family/clan/tribal structure for Alice to live within. It is economical and generally self sustaining, so the AI can even be satisfied that if it goes off line for several megaseconds the humans will be able to take care of themselves and even thrive.
If there is some reason that it cannot create more humans (perhaps some sort of agreement with other AI's), then it can use its vast processing power to start splitting off partial (for it) personalities for Alice to interact with. The best solution here would be to have lifelike androids which the partial personalities inhabit to create the human society Alice will need to thrive, while the bottom end would be for all these personalities to inhabit a virtual environment which Alice can interact with via various social media type systems. One can imagine Alice having friends and even the occasional "unfriending" on a Facebook like platform.
Somewhat less satisfying would be to create various non human android creatures for Alice to interact with. Alice could have pets of her own (robotic dogs and cats, perhaps) or even living teddy bears or a menagerie of creatures like the Scarecrow, Tin Man and Cowardly Lion to work and play with. Since they would or could be sentient beings, Alice may certainly bond with them to some extent, but since they are clearly not human, there will be some elements of the interaction missing.
So long as Alice can live inside some sort of "human" society, she will be comfortable and has the possibility of a fulfilling life, so the AI will need to do this if it is serious about caring for its pet.
[Answer]
**Nothing more.**
Well, maybe a little company, but no need to overdo that.
Most of the answers here conform to the Western *ethos* -work, challenge, control- while ignoring the stress and depression running rampart through our society (people whose skillsets are not marketable or just too common, failed challenges, others being in control). Even in the Western civilization there are many people who are not particularly called to work, challenge and control.
Many other cultures have simply adapted to their environment, and work just what is needed to feed and/or barely cloth them; hunters/gatherers do not even need a so developed sense of property because they own little things that cannot easily replaced. Sure, it comes at a cost both in comfort and in safety (not that the Western world is risk free!), but such cultures are adapted to accept it.
So, given the pets the basic needs, a little freedom of walk and a small social group and don't let those little heads of them fill with strange ideas, and you would be ok.
] |
[Question]
[
The story is in contemporary earth and with same technology.
How can a single human make the Yellowstone explode with the tools available to us now (or with slightly advanced ones, but nothing too sci fi)?
The human in question wants to cause a mass extinction for reasons, and has virtually infinite budget (imagine a Bill Gates but with the absolute monopoly in most sectors all over the world) and high level understanding of mechanics and electronics (Kind of Tony stark).
The "extinction project" will be run by him only (maybe a handful of people, but preferably him alone).
Edit: I'm sorry if I didn't read all the comments and all the suggestions, I'm going through hard times lately. Still thank you very much for all the support.
[Answer]
# Likeliest - but alas already taken - answers
* anon's: "there is no easy way". I'd go for that one, even if it's anticlimactic.
* Ash's: "drill a hole in the magma chamber to trigger outgassing". By far the best "can do" answer, but it requires Yellowstone to already be in a close-to-eruption state (there must be enough dissolved gas in the right conditions).
* underground bombing: same problems in penetrating the magma chamber, plus that of having the bomb(s) - or as Carl Witthoft suggested, the antimatter containment unit - survive the trip.
# Things that would not work
* Save drilling time using the Father of All Kinetic Impactors. There's probably a nice acronym in there, but the project just got mothballed due to lack of the required [hyperdense penetrator](https://en.wikipedia.org/wiki/Impact_depth). Unless we're talking of a Chicxulub event, which would put Yellowstone in the position of the tail wagging the dog.
* Laser drills. Same energy problem of the neutrino heater described below, only much larger. Also, extremely visible.
* Grey goo excavators. The little critters are tough, but the environment down there doesn't really lend itself to nanomachine work, what with those balmy 1500 °C and acid magma. This is actually [one of the reasons](https://xkcd.com/865/) why the computronium apocalypse is going to require some time.
# Way more farfetched possibility
Our sociopathic billionaire wants Yellowstone to erupt even if it were naturally inclined not to. Now, volcanism is driven by heat rising out of Earth's core, and this heat is [largely produced](https://en.wikipedia.org/wiki/Earth%27s_internal_heat_budget) by the decay of heavy elements sunk in the lower mantle.
To increase the core heat directly below Yellowstone, one would need to increase the decay rate of at least the thorium chain of isotopes. There is some preliminary evidence that this [might be possible after all](https://news.stanford.edu/news/2010/august/sun-082310.html).
So, at a ruinous cost, build enough efficient neutrino emitters (this is the most science-fiction-y part: we need an *industrial strength* neutrino emitter) almost wherever you want since neutrinos have no troubles in passing through thousands of kilometers of rock; and aim them on the volume directly below Yellowstone (for better results, the nearer you are, the more vertically you can aim, improving efficiency).
After sufficient time has passed (which depends on the neutrino flux, which depends on the energy and means available, thus on the money) the temperature beneath Yellowstone will have increased and a large "bubble" will be slowly slouching towards the surface. At the same time, surface temperature won't have changed detectably, reducing the possibility of spoiling the surprise.
At this point either let things proceed on their own, or accelerate the works with drilling or bombing.
Of course, radiation counters on the other side of the planet and neutrino detectors almost all over the world will start going crazy, which could be an important plot device - see whether a neutrino scientist can put the data together, triangulate and make the jump and deduce that someone is trying to cook off Yellowstone.
For the sociopathic billionaire, once the emitters are in existence through impressive feats of R&D, there will be the problem of how to camouflage them - hel'll need to set up plausible factories containing a mystery section where terrifying quantities of energy go in, and nothing much comes out (maybe he can try and market some side-effect of the emitter, possibly buying it himself under false identities).
[Answer]
**There is no easy way to make it erupt**
Sure you could say drill a deep enough hole and fill it with explosives or an H-bomb and let it go. But the key here is **pressure**. For Yellowstone to be an extinction level event it needs to have enough magma pooled up to burst. What screws up the planet isnt the lava but all the gas and debris shoved into the atmosphere and it's the surface area of the volcano/caldera and its pressure that gets it there. Yes it has a lot of pressure built up now but popping it prematurely would likely reduce its ultimate effect. Also, drilling a hole and blowing it up reduces the surface area of the eruption point which may reduce the amount of debris shoved into the atmosphere.
There is also the fact that Yellowstone is a closely Federally protected land. The US Federal Government would by no stretch of the imagination allow some trillionaire to start developing it unless they paid off the US debt or managed to pitch to congress a strong geothermal energy production claim that still allowed tourism. Keeping their activity secret would also be impossible because everyone would be curious as to what they were up to.
[Answer]
With a reasonably small (but very expensive) drill actually.
The reason dormant volcanoes like Yellowstone or Taupo are quiet is not because they are no longer being feed heat and magma but because they're in [Isostatic Equilibrium](https://en.wikipedia.org/wiki/Isostasy); the weight of the soil, rock, and even water on top of the magma chamber is in balance with the pressure in the magma chamber such that the volatiles, gases and water vapor, in the magma stay dissolved and don't form any bubbles. Once the process of [Bubble Nucleation](https://en.wikipedia.org/wiki/Nucleation#Examples_of_the_nucleation_of_fluids_.28gases_and_liquids.29) begins in magma, especially in [Rhyolites](https://en.wikipedia.org/wiki/Rhyolite) like Yellowstone, it quickly becomes self sustaining. This causes the molten rock to foam up and eventually explode out of the vent as volcanic ash.
Anything that breaks the equilibrium between the magma chamber and its overburden sufficiently to allow nucleation to begin (including a small eruption at the site) has the potential to cause a major eruption. The most common natural example of this is the draining of a [crater lake](https://en.wikipedia.org/wiki/Crater_lake) releasing water pressure from the vent mouth and allowing gas to begin migrating. Provided that Yellowstone was "ready to go" AKA had a large volume of active, eruptable magma in its chamber a small (30 cm or more should do it) hole in the roof of the chamber could be enough to allow runaway nucleation to begin.
The drill is very expensive, because both the head and the drill string will have to tolerate temperatures close to or in excess of 1000 degrees Celsius. Hardened high temperature alloys will need to be used extensively in the design.
[Answer]
It would be easier to just build a large hydrogen bomb.
Yellowstone is about a 875 gigatonne explosion. Tsar Bomba was designed 100 at megatonnes.
There are little to no fundamental barriers to making a larger nuclear bomb than Tsar Bomba; it was made smaller and not repeated because large, single nuclear bombs are not useful in nuclear war.
Just set of a 100+ gigatonne explosion buried at Yellowstone. Or really wherever you want. If you really want to work Yellowstone in, claim that a 10 gigatonne explosion should trigger the rest of the cascade explosion, setting Yellowstone off early at roughly half power. 10 gigatonne is only 100x larger than already designed nuclear bombs where.
Something as simple as 100 duplicates of the Tsra Bomba design set to go off a the same time would work. Or, add another stage or two to get exponential return from a single bomb.
Tsar Bomba uses a fission trigger to fuel a fusion reaction. They eliminated the 3rd stage of that being used on a fission tamper to release more energy. Simply replacing lead components with the designed uranium would bring it up to its full yield of 100 MT.
Adding a 4th stage would be theoretically possible. As an example, imagine building a sphere of Tsar Bombas that focus their energy on a central fusion or fission target. This 4th stage could involve some exotic material, and part of the plot could involve this rich individual building breeder nuclear power plants, stockpiling this exotic material, and building an underground monitoring facility at Yellowstone.
[Answer]
A sufficiently large bomb should do it. Over pressurizing the dome from above then releasing it (aka a shock wave) should be enough to let it blow; it's a bit like shaking a cola can, then popping the top. A ring of shaped explosives would work better; the more of the overburden you move the better. But either way you need a BIG bomb, something comparable to the [Halifax Explosion](https://en.wikipedia.org/wiki/Halifax_Explosion).
But as Anon mentioned, setting such a thing up would be impossible since it would take up a large portion of one of the most visited federal parks in existence. You are talking about a project taking up 1500 square miles in a heavily trafficked heavily regulated area.
[Answer]
It's my understanding that the "super" in supervolcano is caused by superheated water and gases. You should be able to speed things up by pumping massive quantities of water and industrial pollution like carbon dioxide. Of course that might cool things off initially, but I think a few billion tons of water and gases might speed things up noticeably.
[Answer]
I don't know the math but if the impact from de-orbiting something large into the super-caldera could disrupt Ash's IsoStatic Equilibrium, then your billionaire could start some space business (maybe harvesting tritium from the moon's surface for the soon to be invented fusion reactors)...
then arrange for a landing accident on one or more of the earth-bound space barges.
[Answer]
**No But...**
This is going to be very difficult and expensive and almost certainly would not work, but it might just, although I very much doubt it. First the method then the discussion of the ifs.
If a sufficient number of sufficiently powerful hydrogen bombs could be placed at the bottom of enough shafts dug deep enough, in a ring formation centred on the most volcanically active part of Yellowstone, (and the Government allowed it) then perhaps.
If they were all let off together the blast would concentrate inward and downward giving a gentle (by geological standards) kick start to the energy and magma available to trigger a reaction from Mother Nature.
**But there are all those ifs**
Can this person gather a sufficient number (10-50+?) of sufficiently powerful (1Megaton+?) hydrogen bombs? No mean feat by anyone however rich. I would say not, but it can’t be totally ruled out.
Can the shafts be dug deep enough? This is all very speculative – it would depend on how far they could be from the epi centre and on how sophisticated the technology available to drill into hot and very hot rocks to great depth. Probably not far enough and not deep enough, but again it can’t be ruled out entirely.
Would they even be allowed in to do anything at all or could they do this secretly. Almost certainly no and no again, but stranger things have happened and it could not be ruled out entirely.
Finally would it actually work? Well you can guess my response here – probably not, but…
Edit - I suppose even if it didn't work, the use of a sufficient number of hydrogen bombs aided by more limited volancim might still cause a nuclear winter and the fiend could claim he had set off Yellowstone, even if he hadn't, although I doubt anyone would be interested by then.
[Answer]
[](https://i.stack.imgur.com/wyK2T.png)
Yellowstone is just one of several super volcanoes found across the earth capable of ejecting so much ash and sulfur dioxide into the atmosphere that the planet would experience global cooling. Not only is an eruption likely, it's likely enough that scientists at NASA have been figuring out ways to lessen the likelihood of an eruption.
Yellowstone sits on top of an enormous magma chamber which can fuel a volcanic eruption many times greater than anything we can imagine. The ash alone would bury most of North America in up to 1 foot of ash. It would cripple the ability to grow food over much of the arable land across Canada and the US. That ash would shut down aviation across the planet.
Yellowstone stays dormant because it's leaking 60-70% of the heat from the magma pocket into the atmosphere. If you want to start an eruption, you only have to figure out a way to decrease the heat leakage. You don't need hundreds of nuclear bombs, you need to stop the venting of steam and water. Once the magma heat reaches a certain threshold, then a cataclysmic eruption is inevitable and unstoppable.
* <http://www.bbc.com/future/story/20170817-nasas-ambitious-plan-to-save-earth-from-a-supervolcano>
* <https://www.livescience.com/20714-yellowstone-supervolcano-eruption.html>
Good luck.
[Answer]
Actually forcing an eruption is very difficult as others have noted and almost impossible to do so stealthily.
I'd take a different approach. Sociopath Billionaire is playing a long game (in my take), so he sets up a Yellowstone monitoring / containment system, all with his own money and all for the public good. He's lauded by everyone and the government becomes more trusting and eventually leaves Yellowstone alone just getting (and trusting) regular updates from the Billionaires team.
A few years into the program and SB gets indications that Yellowstone will blow soon. He's the only one in his organisation with access to the complete data, he's very into compartmentalisation.
So now all he has to do to complete his fiendish plan is to tweak the data so everything looks okay. Then quietly render his containment system less and less effective, still hiding the data. He'd also need to take care of secondary signs of imminent eruption that might be noticed by other (older) monitoring systems elsewhere.
[Answer]
**Want to improve this post?** Provide detailed answers to this question, including citations and an explanation of why your answer is correct. Answers without enough detail may be edited or deleted.
Find the biggest asteroid you can maneuver, hide it with UV to radar absorbers, and send it to Yellowstone for high velocity impact.
[Answer]
LSemi rejects an impact trigger but I think that is invalid. Yes, grabbing an asteroid and tossing it at Yellowstone isn't an answer because to punch deep enough it's too energetic, rendering the eruption moot.
However, what if you don't throw an asteroid? Go out into the asteroid belt and start mining, the objective being to build a rod a few miles long but only tens of feet wide and throw that. Make sure it hits straight.
] |
[Question]
[
A cowboy of the 19th Century got dragged back into the past (just in case, stable time loop does not apply here since it also has an alternative timeline/universe), after some feats of battle, the King and nobles were extremely impressed, especially with his gun, the problem is that his ammo is limited.
Would it be possible for the king and nobles, using everything they have, finding the best and brightest of the era to research..etc.. to produce bullets for the cowboy's revolver (with some unused bullets given to them), or better, the revolver itself?
[Answer]
# It depends on the pistol
[The 19th century spans a number of revolutions in firearms](http://www.militaryfactory.com/smallarms/guns-1800-1899.asp) including percussion caps, revolvers, cartridges, smokeless powder, and semi-automatic pistols. It spans everything from a [single shot, muzzle loading, flintlock pistol](https://en.wikipedia.org/wiki/Flintlock#Pistols) using black powder...
[](https://i.stack.imgur.com/hcmdP.jpg)
To a recognizably modern cartridge revolver like the iconic [Colt Single Action Army](https://en.wikipedia.org/wiki/Colt_Single_Action_Army) of 1873, but still black powder...
[](https://i.stack.imgur.com/mguHP.jpg)
To the first commercially successful semi-automatic pistol, the [C96 "Broomhandle" Mauser](https://en.wikipedia.org/wiki/Mauser_C96) in 1896.
[](https://i.stack.imgur.com/1i42x.jpg)
---
# Black Powder, Yes. Smokeless Powder, No.
Modern firearms use ["smokeless" powder](https://en.wikipedia.org/wiki/Smokeless_powder) which is more powerful than black powder and, surprise, doesn't produce smoke. It's made of various things including nitrocellulose. None of this would be available in 14th century England and a cowboy would not know how to make it.
While smokeless powder was invented in the mid 19th century, black powder was used well into late 19th century. Fortunately for your cowboy, many of the pistols available to them would be black powder. And [14th Century England would be familiar with black powder](https://en.wikipedia.org/wiki/Gunpowder#Mainland_Europe). A little careful experimentation would find the right amount and grind to work safely and effectively.
# Flintlocks Are Easy
A flintlock is easy enough to deal with. All you need is a lead ball and some black powder. 14th century England would have plenty of lead, it's a byproduct of silver mining. No percussion cap is necessary, the flint striking steel provides the spark to light the powder.
With some care and trouble they could probably even copy a flintlock. The biggest problem would be the springs and metallurgy, but the very simple design gives them a lot of wiggle room. In a pinch they could replace the flintlock with a [matchlock](https://en.wikipedia.org/wiki/Matchlock).
# No Semi-Automatics
The lack of smokeless powder rules out any sort of semi-automatic pistol. Black powder leaves a lot of residue which would rapidly gum up the moving parts.
In addition, early semi-automatic pistols like the Mauser C96 were [recoil operated](https://en.wikipedia.org/wiki/Recoil_operation) meaning they use the recoil energy from firing the bullet to work the action and chamber the next round. Since black powder is weaker than the smokeless powder they're designed for, it would not have enough recoil energy to cycle the action. You'd have to cycle the gun manually.
# Brass Cartridges Are A Problem
At the other end of the spectrum is any pistol that takes [cartridges](https://en.wikipedia.org/wiki/Cartridge_(firearms)#Modern_metallic_cartridges) like the Colt Single Action Army / Peacemaker or the C96 Mauser. Cartridges required a lot of trial and error to get right. They require a very thin brass case made to exacting tolerances which 14th century England would not have the metallurgy to make in any quantity.
As someone who's accidentally fired the wrong caliber cartridge in a pistol, a [.40 in a .45](https://www.youtube.com/watch?v=eE5trZ8VD-k), you don't want to get this even a little bit wrong. At best the burst case gets stuck in the cylinder. At worst it blows up in the shooter's face.
What about reloading cartridges? A cowboy might know how to do that, but not all cartridges are reloadable. And you have the serious problem of replacing the primer (see below).
# Primers Are A Problem
Anything after a flintlock requires a primer, some chemical sensitive enough to explode when struck by the hammer, but inert enough to not go off from being jostled around. Primers are made of [mercury fulminate](https://en.wikipedia.org/wiki/Mercury(II)_fulminate) which would not be available in 14th century England. Bullets have primers in their base. Others use little caps like a cap gun.
# The Sweet Spot: A Cap And Ball Revolver
A cap and ball revolver is a revolver that doesn't use metal cartridges. Instead, each cylinder is loaded with black powder and a lead ball like a muzzle loader. This gives our cowboy the relative speed and mechanical simplicity of a revolver, without having to try to make brass cartridges. A good and popular example is the [Colt 1851 Navy](https://en.wikipedia.org/wiki/Colt_1851_Navy_Revolver).
[](https://i.stack.imgur.com/seeQe.jpg)
However, it does need [percussion caps](https://en.wikipedia.org/wiki/Percussion_cap) filled with an explosive primer. This is going to require some chemistry that doesn't exist in the 14th century and that your cowboy is unlikely to know.
It might be possible the revolver could be retrofitted to use flint or a [match](https://en.wikipedia.org/wiki/Matchlock) in place of the cap, but I've never heard of such a thing.
---
# "Making X Is Easy! Just Put Y into Z!"
There's a bunch of comments of people saying that making this or that chemical is easy. There is no "just" when it comes to making explosives. And there is no "just" for doing anything in the 14th century. The question of whether a 19th century cowboy could, even with all the help of the King of England, make smokeless powder and primers for their gun is one that deserves its own question and answers. But here's my take.
Your typical cowboy, or anyone from the 19th century, will have no chemistry education. If it's early enough in the 19th century they're lucky they can read. Maybe they conveniently worked in a gun shop, but the probably weren't mixing explosives. So the author has to explain why this 19th century cowboy knows how to make smokeless powder and primers from scratch.
If they were making explosives, they definitely weren't mixing up the ingredients themselves. If they were then they're not a cowboy, they're a chemist. Even in the 19th century one can order a bottle of this or that and be sure of what they're getting. In the 14th century there are no purified chemicals to work with. There are few standard measurements. Even if our increasingly atypical 19th century cowboy knows that, for example, [Aqua fortis](https://en.wikipedia.org/wiki/Aqua_fortis) is [Nitric Acid](https://en.wikipedia.org/wiki/Nitric_acid) necessary for the production of [guncutton](https://en.wikipedia.org/wiki/Nitrocellulose), do they know what strength the solution they're buying is? Do they know what impurities it has in it? Do they even know it's what they say it is? Working with impure or mislabeled chemicals is a good way to get blown up.
Finally there's the problem of remembering formula and procedure. There are no chemistry textbooks to refer to in the 14th century. Unless this cowboy is like [Ash Williams](https://en.wikipedia.org/wiki/Army_of_Darkness) and brought a practical chemistry textbook along with them in the trunk of their car saddlebags of their horse...
[](https://i.stack.imgur.com/fAYCF.png)
...they won't be able to rattle off the formulas and procedures for making mercury fulminate and nitrocellulose, much less make it consistently to the tolerances for the smokeless powder in their bullets to avoid damaging their irreplaceable gun.
Let's list it out. In order to make smokeless powder and primers for their revolver our "cowboy" needs...
* To have memorized the formulas, ratios, and procedures.
* To know the 14th century names for the ingredients.
* To somehow find and verify pure samples of the ingredients.
* Not blow themselves or their gun up in the process.
It's not impossible, rather those are the plausibility hurdles the OP's story has to overcome.
[Answer]
One aspect of the question which other answers haven't yet covered:-
>
> ...or better, the revolver itself?
>
>
>
The problem with everything involving gunpowder is making sure all of the bang goes out of the front, otherwise you're not holding a firearm, you're holding a pipe bomb. A 14th century armourer would have extensive experience with brass cannons, and would likely be aware of hand cannons. But with that, they'd be all too bitterly aware of what would happen with any small flaw in the metal, because cannon regularly blew up and killed their crews. Metallurgy simply wasn't anywhere near advanced enough to make a halfway modern firearm.
The 14th century armourer could certainly identify that the revolver is made out of steel. He could probably even take some moulds and produce something that looked similar. There's even some chance he could drill the barrel fairly cleanly, using the same kind of drills used for piercing stone. But the steel he'd be using would be nothing like good enough for the gun to hold together, so it would be a lot more dangerous to the user than to the target!
A more profitable line would be to use some of the cowboy's knowledge relating to the use of firearms. The problem isn't just having them, it's using them effectively. It took a hundred years to get the arquebus, and another hundred years before people worked out how to turn it from an isn't-this-cool gimmick into an actual weapon that worked effectively on the battlefield. Hand cannons did exist, but the cowboy could take his knowledge of what a musket looks like and basically invent the arquebus early. Bringing volley fire concepts to primitive hand cannons would then make the new arquebus a battle-winner, as would be the invention of the bayonet so that they wouldn't need a protective screen of pikemen. He could also suggest the star fort concept, which would be a dramatic change to the defensive side of things and would be as valid for defenders with bows as it is for firearms.
In the meantime, the main limiting factor on development is always investment. If the king is keen on firearms and is pumping money into them, he's inevitably going to attract the best and brightest metallurgists and chemists from across Europe, and that's likely to accelerate a lot of development.
[Answer]
*Assuming your cowboy is a pure consumer, he knows only how to load, fire and maintain his gun.*
Luckily cannon have been invented in the 14th Century, they've been around in Europe for 50-100 years. Gunpowder is a known compound and it doesn't change much until smokeless powders in the very late 19th Century, so it's likely the right propellant for the weapon.
Any blacksmith will be able to make the bullets, he just needs some lead and a mold. That's a minor detail.
However the bullet cartridge and firing button is a much tougher object to make to the correct tolerances and would be best passed to a jeweler.
[Answer]
The *bullets* are easy. Cowboys in the 19th century did actually cast their own lead bullets. But the chemistry for *percussion caps* (or for any kind of primer really) simply did not exist in the 14th century (fulminate of mercury was discovered mid-17th century and refined at the end of the 18th century). Not to mention: steel is very expensive and nobody knows how to make it with consistent properties -- nobody has ever seen molten steel, much less cast it -- there are no precision lathes able to process hard metal -- there is no simple way to make measurements more accurate than maybe half a millimeter -- there are no precisely standardized units of measurement -- nobody has thought of mass production -- etc. The 14th century was a very different world from ours.
[Answer]
No, they could not have done it. The problem is that [fulminates](https://en.wikipedia.org/wiki/Fulminate) were unknown at that time and knowledge of fulminates would be necessary to make the percussion cap for the bullet.
Making the cartridge casing would have also been very difficult with no help. Brass was largely unknown at that time and drawing bronze into a casing without it cracking would have difficult.
The gun could have been made... almost. The main body of the gun would be achievable, although it would have been fantastically expensive because it would have taken a great deal of meticulous work. The problem would be the springs. In the 15th century they did not yet have the knowledge to make the kind of tempered wire necessary to make a small springs. It is possible that might have been able to find some way around this problem, but it would be difficult.
] |
[Question]
[
One day, I am randomly teleported to somewhere else where I meet some aliens. These aliens are very technologically advanced and after figuring out communication, we establish a rapport. The aliens, being the benevolent type, want to help me get home, and, as luck would have it, they have a portal device which can spontaneously open a stable wormhole across any distance.
Unfortunately, the aliens don't know where Earth is, and I'm reasonably certain that I'm still somewhere in the milky way--I used to have a photo of the galaxy as a desktop wallpaper and I recognized it when the aliens showed me.
**The parameters:**
* The Aliens are isolationist and almost all their data about space was gathered with telescopes. As such, data may be hundreds of thousands of light years out of date.
* The Aliens have mapped every single star and most larger planets (in the Milky Way) telescopically. More specifically, if you knew which entry was Earth's on their database, it would show detailed information about the Sun along with stating that there are two gas giants (with mass estimates) and between 4-8 other smaller planets.
* The aliens haven't received any radio transmissions from Earth (I am apparently over 200 ly away)
* The aliens are willing to teleport out probes to search for radio signals or take a closer look at a some systems but their generosity is finite--they won't saturate the entire galaxy to find Earth.
* My knowledge about the solar system is at an above average highschooler's level. I can list and describe planets in the Solar System, I can identify or approximately draw several constellations, and I know various random trivia such as the fact that the Moon's apparent size is the same as the Suns'. I *don't* know any exact numbers like planetary masses or diameters and I don't know anything about the specific type of light the sun gives off, although provided with examples, I would be able to tell what light temperature "feels right".
**Question:**
What search strategy should the aliens employ to find Earth as fast as possible and with the least amount of probes?
[Answer]
Instead of searching for Earth or Sun directly, you could scan for notorious star systems close to Earth. As an atronomically interested person, you probably know some bits about some of those, due to their interest for future human space exploration.
The Alpha Centauri system is a triple star system, so through the properties of all the stars (as well as you can remember them) and their constellation with each other you have a lot of properties you can search the database for. Similarly, Sirius is a binary star and a very bright system in the local galactic area and very close to both Sun and Alpha Centauri. You can search for two systems with these properties in close proximity, and then scan the nearby systems for a single star system which matches Sun in colour, number of planets and gas giants.
I'm not an expert on astronomy, so there might be even better "anchor" systems nearby that I'm not aware of.
[Answer]
# 1. Draw the Milky Way
You mention that you know what the Milky Way looks like. This is good, because it won't actually look the same way from different points in the galaxy - from closer to the centre, it would take up more of the sky, from further above the plane of the spiral, it would show a different shape.
So start your search by simulating its general shape in its sky at different points in the galaxy and picking the ones that look the most familiar. This will rule out maybe 90% of the galaxy.
# 2. Make a long-list
Now search the alien database for star systems within the possible zones you've identified, and list out all the star systems with the right number of planets.
Filter based on any other facts you can remember - for instance, the sun isn't a binary star, which might rule out some systems.
# 3. Send your first few probes
Send out a probe to a random entry on the long-list, and check for Earth's radio transmissions. Assuming you don't get lucky first time, take some good pictures of the sky as seen locally.
Repeat this a few times, but make sure the locations you pick are as spread out as possible across the galaxy.
# 4. Update the star charts
You now have a bunch of star maps from different perspectives in the galaxy. Confusingly, these will be subject not just to three-dimensional parallax effects, but a kind of "four-dimensional parallax" (there's probably a proper name for it) because they'll be seeing the same features with different light-speed delays.
Nonetheless, you should be able to simulate approximately what the sky would look like from places in between, based on the aliens' detailed data and the perspective correction from the probes.
# 5. Find a familiar sky
Scroll through the photographed and simulated skies until you find one that has some features you think you recognise. Send a probe to a system near that location. As before, listen for radio transmissions, and if you haven't found Earth yet, take some more photos to check and update your constellation simulator.
As you're now looking in much more focussed areas of the galaxy, you'll hopefully find Earth before the aliens' patience runs out and they put you in a zoo.
[Answer]
There are believed to be about 100,000,000,000 to 400,000,000,000 stars in our galaxy.
That is a lot of stars to check. If it takes one second to check if a star is the Sun - and it might take a loot more time than that - you can check 60 stars per minute, 3,600 stars per hour, 86,400 stars per day, and about 31,557,600 stars per year. Thus you could check 315,576,000 stars in a decade, about 3,155,760,000 stars in a century, and about 31,557,600,000 stars in a millennium. Thus it would take about three thousand to twelve thousand years, to check every star in the galaxy at the rate of one star per second, which seems much too fast for me to believe.
When I was a child I read *Rusty's Space Ship*, by Evelyn Shibley Lampman, 1957. Two Earth children, Rusty and Susan, help a lizard like alien find his way back to his home at Eopee. They travel from planet to planet to planet in our solar system, trying to find Eopee. Finally the alien happens to sing in his sleep:
>
> A messenger from Eopee
>
>
>
>
> in Andromeda galaxy
>
>
>
>
> my training is the very best
>
>
>
>
> I passed with honors every test
>
>
>
And they wake him up and tell him what he sang in his sleep. So he takes them back to Earth and tells them he will be able to find his way back to Eopee now.
And a few years later, when I knew more about astronomy, I began to doubt whether the alien ever got back to Eopee. The Andromeda Galaxy is even bigger than the Milky Way Galaxy and has even more billions of star system. Unless the alien clearly remembered the directions back to Eopee, he would be forever trying to find a needle in a haystack searching for Eopee in the vast Andromeda Galaxy.
Go back to the beginning. How much knowledge of astronomy does someone need to tell if they are in the Milky Way Galaxy?
Maybe they will ask the aliens to show them pictures of the nearest galaxies. Maybe they will recognized images of the large and Small Magellanic Clouds and the Andromeda Galaxy M31 and the Triangulum Galaxy M33. And if the images are clearly taken from the same angles as telescopic images of them from Earth, then the aliens must be in the Milky Way Galaxy.
There is a theory that planets suitable for life have to exist in within a broad ring shaped area of the galactic disc of the Milky Way Galaxy, not too close or too far from the center of the galaxy. So once the aliens agree that you come from their galaxy, if they believe that theory then they will assume that Earth is within that ring shaped region of the galactic disc, eliminating tens or even hundreds of billions of stars, though tens or hundreds of billions of stars will be left.
If you can compare Earth spectral types of stars with the alien's system of classification, and if you know that Earth is a spectral type G0V or G2V star, and if you can find what type of stars those are in the classification of the aliens, you can eliminate maybe 90 or 95 percent of stars in the zone. And if you tell the aliens that our Sun is almost certainly a single star that should help the elimination.
If the aliens can deduce how much radiation Earth gets from the Sun from an examination of you, and if they can figure out what type of star the Sun is in their classification and thus its approximate absolute luminosity, they can estimate the length of Earth's year with a rough range in their timescale.
If you tell them that Earth astronomy books claim that the disc of the Milky Way is about 100,000 (Earth) light years in diameter and about 1,000 or 2,000 (Earth) light years thick near Earth, comparing those figures with their figures and with the approximate length of an Earth year and thus of an (Earth) light year compared to their units of measure, that will be helpful.
And doing so will be really helpful if you also remember that Earth is supposed to be about 25,000 to 28,000 (Earth) light years, from the super giant black hole at the center of the Milky Way Galaxy. That will enable the aliens to draw a ring around the super massive black hole in Milky Way Galaxy with a radius of their distance units that is equivalent to 25,000 to 28,000 light years. And then the aliens can draw an inner and an outer circle approximating the degree of uncertainty in those figures.
The ring of possible positions of Earth derived from the distance of Earth from the super giant black hole should be a much narrower ring than the ring deduced by the fact that there is life on Earth, so it should be very helpful to the aliens in narrowing down the field of search.
I note that as seen from Earth, The Andromeda and Triangulum galaxies are more than 90 degrees from the galactic center, while the Large and Small Magellanic Clouds are on the other side of the Galactic center and about 60 degrees from the galactic center. So if you can remember that, it would be a good indication which side of the galaxy Earth is in.
An Astronomical Unit (AU) is the average distance between Earth and the Sun. Astronomers measure the angle to a star at two times, six months apart, when Earth is on opposite sides of the Sun and is 2 AU apart. A distance of one parsec is the distance at which a separation of one AU would have an angle of only one arc second. A parsec is equal to about 3.26 light years or 206,264.806 AU.
Back in the 1830s, using a baseline of only 2 AU for their measurements, astronomers were able to measure the tiny six month changes in the positions of stars in the sky accurately enough to find the approximate parallaxes of three stars, and thus their distances from Earth. 61 Cygni is about 3.4947 parsecs, or 11.398 light years, or 720,833.59 AU from Earth, Alpha Centauri is about 1.340 parsecs, or 4.37 light years, or 276,363.5 AU from Earth, and Vega is about 7.68 parsecs, or 25.04 light years, or 1,584,113.6 AU, from Earth. And astronomers were able to measure their approximate distances with the instruments available in the 1830s.
And today Earth astronomers have much better instruments to measure tiny angles much more precisely and accurately. And some such instruments have been packed aboard the Gaia spacecraft.
>
> Gaia is a space observatory of the European Space Agency (ESA), launched in 2013 and expected to operate until c. 2022. The spacecraft is designed for astrometry: measuring the positions, distances and motions of stars with unprecedented precision.[7][8] The mission aims to construct by far the largest and most precise 3D space catalog ever made, totalling approximately 1 billion astronomical objects, mainly stars, but also planets, comets, asteroids and quasars among others.[9]
>
>
>
[https://en.wikipedia.org/wiki/Gaia\_(spacecraft)[1]](https://en.wikipedia.org/wiki/Gaia_(spacecraft)%5B1%5D)
If the aliens have the ability to send equivalents of the Gaia spacecraft, or much more advanced versions of it, through wormholes to any place in the galaxy, they can have pairs of those automated observatories observe a star from locations that are many light years or parsecs apart, and thus with baselines, tens, and hundred of thousands, and millions, of times as long as the baselines used by Earth bound astronomers, and they can measure the directions and distances to that star, and thus its position in three dimensional space, much more accurately than Earth bound astronomers. And they can do that for all of the billions of stars in our galaxy. And by measuring the apparent magnitude of a star at a specific distances, they can calculate its absolute magnitude, and thus calculate how bright it will appear from any point in the galaxy.
So the aliens will ask you about prominent constellations as seen from Earth. And with luck you should be able to draw not too bad depictions of a few, such as the Big Dipper and the little Dipper. And the most prominent Constellation, Orion. And by great good luck the distances to the stars in Orion which are brightest and most visible as seen from Earth happen to differ much less than the distances to the brightest stars in most constellations do. Thus Orion will be recognizable at a much greater range of distances than most Earth Constellations are.
And if you happen to remember that, as seen from Earth, Orion is almost opposite to the center of the Galaxy, the aliens should come up with a smart idea. If the aliens select points in the ring around the center of the galaxy where they think Earth should, be at one degree intervals as seen from the center of the galaxy, each point should be only about 440 to 490 light years from the next. And that should be close enough.
Then for each of those 360 points they can generate images of the sky as seen from that point, opposite to the center of the galaxy, with the apparent positions and the apparent magnitudes of the stars calculated. And at least one of those points should show a rather distorted image of Orion. And they they can calculate the appearance of the sky from a number of equally spaced points around that point, and find a point where Orion looks most like it is seen from Earth.
And then it will be helpful if you can remember the constellation of Taurus, which appears to the right of Orion from the northern hemisphere. Many of the brighter stars of Taurus form a sort of V shape and are in the Hyades star cluster about 153 light years from Earth. But a star along one side of the V, on the side toward Orion, is Aldebaran, which about 65 light years from Earth. Another star cluster, the Pleiades, about 450 light years from Earth, appears to be on the side of the Hyades away from Orion as seen from Earth.
So a spot where Taurus is recognizable is likely to be close to Earth.
So if the aliens can produce images of Taurus and Orion you recognize, they can send probes to study many star systems in that area of space to see if they are your solar system.
And I can't help wondering if someone with merely average high school knowledge of astronomy would be able to remember all the details which would help the aliens find Earth for them. I can't help thinking that if by chance they had a pocket book of astronomy on them when taken from Earth to the alien's world that would help the aliens a lot.
My answer to this question
[https://worldbuilding.stackexchange.com/questions/120295/how-to-find-earths-relative-position-anywhere-in-the-galaxy-without-any-markers/120391#120391[2]](https://worldbuilding.stackexchange.com/questions/120295/how-to-find-earths-relative-position-anywhere-in-the-galaxy-without-any-markers/120391#120391%5B2%5D)
discusses how someone with more astronomical information could find his location in space.
[Answer]
**If there are details about planets and star characteristics you could use a process of elimination according to planet / star characteristics.**
I, like your protagonist, have a knowledge of the universe at an above average high schoolers level, though less sure about "above". But I can use excel.
Here is how I would do it if the alien database were in excel.
I would sort by planets, looking to isolate the subset of planets with either oxygen nitrogen atmospheres, or liquid water or both. Those are Earth candidates.
I would probably turn up a few hundred million. I would sort those planets according to moons; one and only one. Then, assuming that Earth's moon is unusually large I would exclude planets with a moon in the bottom 50% of size range for those moons. Now there are a million candidate planets.
Then I would sort those systems for the presence of 2 and only 2 gas giants. That would narrow it down to tens of thousands.
I would sort systems by star type, excluding the reds and giant stars. Now that is down to a few hundreds.
If I can sort gas giants by presence of a ring or not that would be helpful because maybe Saturn is special.
Now there are a hundred or so Earth candidates. I would look at them one by one. Hopefully the aliens have a visual catalog that makes sense to me of how the different planets and stars look. I would look for blue seas and white clouds. I might be able to identify Luna or Jupiter.
[Answer]
**Frame challenge** (especially if this is science-based)
>
> "The Aliens have mapped every single star and most larger planets (in
> the Milky Way) telescopically."
>
>
>
**No they haven't.** To do this telescopically simply isn't feasible. Apart from anything else, stars are hidden behind other stars. Also our view towards the center of our galaxy is blocked by the HII clouds - or dust. We can see the hidden parts only at certain wavelengths. <https://en.wikipedia.org/wiki/H_II_region>
>
> There isn’t a way to simply count the number of stars in the Milky Way
> individually ...
> <https://asd.gsfc.nasa.gov/blueshift/index.php/2015/07/22/how-many-stars-in-the-milky-way/>
>
>
>
If you have any doubt, just watch this <https://youtu.be/X-3Oq_82XNA>
[Answer]
## How well you can reliably narrow it down
There are an estimated 100-400 billion stars in the Milky Way.
**Identifying our Star Type:**
Sol is a G-Type Main Sequence Star, or as most people would simply call it: a yellow star. Only about 1/10 stars are yellow so this should narrow your search down to about 10-40 billion possible stars.
**Identifying our Galactic position:**
This could potentially be the best tool in your tool kit depending on how exact your traveller's memory is and how good his wall paper was. If your traveller only remembers about how far from the core of the galaxy Sol is, then this could get it down to about 1-20 billion possible stars depending on how confidently he can remember this detail, but if your traveler really knows his stuff (which he may or may not based on your description), then he would be able to identify where Orion's arm splits off into Orion's spur, and then be able to show that Sol is somewhere in this area. This should be enough to get within about 5000 ly of Earth. Since there are only about 600 million stars in this area, this would reducing the number of possible star systems to about 60 million.
## How the inaccuracy of the alien star charts would foil you
Even 60 million is still too many to count without narrowing it down more, and this is where you run into huge risks of failure. Filtering large lists is all about throwing away results without ever actually looking at them. So, if you apply a single filter to your list of stars that drops Sol, you will never find it; so, you have to be very careful about utilizing the following methods:
**Identifying our neighbors:**
Most people know that Alpha Centauri is about 4 light years away and is part of a trinary star cluster. This is where you start running into issues. We humans consider Alpha Centauri to be a trinary star system but what happens if the aliens have a different definition of a star system. Perhaps they don't consider class M5 dwarves like Proxima Centauri to be stars at all or perhaps it orbits at too great of a distance to meet thier definition of trinary star system. So, in thier records, Alpha Centauri may be a binary star orbited by what they still consider to be in the range of "thermal emitting gas giants" or something that they have a unique word for for things between "stars" and "gas giants". Or just a binary star with a really close neighbor star. Or, your travel does a bad job describing light years; so, the aliens are actually looking at the wrong distances away. There are all sorts of ways aliens might classify things differently than we do that could cause major issues. This means that if you filter only for G-Type Main Sequence Stars that are about 4ly from trinary star systems, there are multiple possible reasons that your alien database will throw out Sol as a possible match.
Even if you get lucky and don't throw it out, G-Type main sequence stars and trinary star systems are both so common, that you will still have thousands upon thousands of stars left to go through needing yet more filters.
**Identifying our planets:**
>
> ...if you knew which entry was Earth's on their database, it would show detailed information about the Sun along with stating that there are two gas giants (with mass estimates) and between 4-8 other smaller planets.
>
>
>
The number of planets becomes an even bigger issue. Your highschool student does not know how many planets the aliens know about in the Sol system. He also does not know how to accurately describe thier sizes; so, when you query a database containing somewhere between what is now a number somewhere between tens of thousands and 40 billion records (depending on what you've already done to narrow it down) being close is still not good enough. Will the aliens be looking for stars with 8 planets? or is it 9? or maybe 15? See we humans live here and even we can not all agree on how many planets are in our own solar system. Either way, the aliens will be so busy looking at stars with 8-15 planets in thier database that they will never get to some poorly documented star with only 6 known planets in thier database. Because thier records are not perfect, there is a good chance you will filter out our solar system and never find it if you try to look by planets.
**Photographic Fidelity:**
Let's say the alien database is really good, and your traveler does a great job of explaining things getting you to the point where you can actually narrow down the list to a manageable set that actually includes Sol. What do you do? Well, the most efficient thing would seem to be to look at the photos they have of our solar system. This of course raises the question: could you even recognize it or would you throw it out will all the other near matches? When it comes to taking a picture, there are all sorts of factors that can make the same familiar thing look different. When photographing things in space, how you expose your image based on that tinie-tiny dot of light in the sky makes a huge difference. Below are 3 images taken of Saturn by NASA. If the aliens sat you down to look at a lineup of a few thousand Sol like systems, and they randomly showed you one of the 3 photos, would you know for sure that you are looking at Saturn or just one more of the many many ringed gas giants we have in our galaxy?
[](https://i.stack.imgur.com/pME7p.png)
## How the inaccuracy of human memory would foil you
**Identifying our constellations:**
If your traveler has an actual picture of our night sky saved on his phone, then it would be relatively easy (with enough computational power) to line up our constellations with our exact position, but these kind of things have to be very precise. If you are just trying to draw constellations from memory, this will more likely than not lead you on yet another wild goose chase. What you draw as the big dipper will likely more closely resemble many many constellations as seen from other stars; so, if your sketch is not accurate enough, you might end up filtering Sol out of your candidate list in trying to narrow it down.
Then there is the bigger problem of actually trying to be too specific. Our constellations are often idealized versions of actual stars where parts of the constellation that "make up the image" are not actually the brightest stars in that part of the sky. So if you don't draw out orion's arm and bow, your image will likely be to vague to find a match, but if you do draw them out, you are in even worse shape because all the missing stars from your sketch will nullify Earth as an option at any threshold of apparent magnitude.
[](https://i.stack.imgur.com/bFXjm.png)
**The devil is in the details**
This leads to the final problem of human error. What happens if your student remembers anything wrong? He is going off of memory after all, so if he remembers just one detail wrong like maybe he thinks Alpha Centauri is 3.4 ly instead of 4.3ly or maybe he does not remember Mars having moons or something like that. On a test like this, anything less than a 100% is a failing grade.
In summary, it is very unlikely that a traveler is going home without either a much better than high-school level understanding of galaxy or some kind of citable documentation.
[Answer]
>
> I can list and describe planets in the Solar System, I can identify or approximately draw several constellations,
>
>
>
This is what can bring you home, if possible at all. It would be better if, together with drawing some constellation, you could also indicate their relative position in the sky.
If they have a catalogue of all the stars in the galaxy, they should be rather easily be able to build a 3D representation of the same galaxy. From there to calculating the appearance of the sky from any point of view would be doable (it's something we can pull out with our tech level).
Since you know and can draw several constellations, you can either scroll the list to search for star systems similar to the Sun and check what the sky looks like from their point of view, or scan the point view searching for places where the sky shows the features you can describe and then search for Sun like systems in the area. In both ways it would be probably better to have an expert system do the job for you, I suspect there will be a large number of stars to check.
Once you have the list of candidates, you can try to weed it out further and hope it's not longer than the list of probes they are willing to send.
[Answer]
Expanding further on my comment to another answer...
You remember part of the lyrics of "the galaxy song" from Monty Python's meaning of life (or otherwise have some reason to remember similar statistics):
>
> Our galaxy itself contains a hundred billion stars; It's **a hundred
> thousand light-years side to side**; It bulges in the middle sixteen
> thousand light-years thick, But out by us it's just three thousand
> light-years wide. We're **thirty thousand light-years from Galactic
> Central Point**, We go 'round every two hundred million years; And our
> galaxy itself is one of millions of billions In this amazing and
> expanding universe.
>
>
>
This gives the approximate distance from earth to the centre of the galaxy as 30,000 light years, and also calibrates what a light year is for the alien's benefit as 1/100,000 of the distance across the galaxy.
So far this only gives us the (very approximate!) distance from the centre of the galaxy... but you also remember that the centre of the galaxy from our point of view is [Sagittarius A\*](https://en.wikipedia.org/wiki/Sagittarius_A*), and of course that the nearest galaxy to us is the Andromeda galaxy in the Andromeda constellation.
The relative position of the galactic centre to the Andromeda galaxy would greatly narrow down the search area. It would be even more useful if you can identify and remember the correct relative location in the sky from Earth's perspective of some other nearby galaxies to improve the triangulation and reduce the search area. In particular a comment from someone more familiar with astronomy than I suggests the [Magellanic Clouds](https://en.wikipedia.org/wiki/Magellanic_Clouds) - being different distances away, they would only appear at the right apparent spacing from someone in a similar region of our galaxy.
Also, [supernovae](https://en.wikipedia.org/wiki/History_of_supernova_observation) that you know about (where in the sky they appeared as viewed from earth, and when in earth's history they were recorded) could be useful as further triangulation points if they're ones the aliens also know about. If the aliens know exactly where and when in the galaxy the supernova actually occurred, then the number of years after the event that it was observed from earth would give a distance... but for many of these it could be uncertain WHICH supernova was the one we saw given that there are potentially thousands of [light-]years of uncertainty about the position we were observing from, and large numbers of supernova events that may be observable over such a time span. That could even make an interesting blind alley for the story - the aliens correlate the only supernova you can remember with one that hasn't been observed from earth yet.
The exact shapes of constellations would seem less useful initially, but once you've got an approximate location, the aliens' database could perhaps come in useful to reconstruct what an observer at various places in the search area might see (unlike the questioner who assumed planets would be known about, I'm assuming only the position and brightness of each star is known). This can also be correctly aligned (using the known positions of the galactic centre and andromeda galaxy) so that you know which constellation you should be looking for in which part of the sky as reconstructed from the star charts.
I could imagine it working something like this:
The aliens put together a database of all known stars with their brightnesses and exact positions and velocities to create a simulation of what the sky would look like from any specified position as of the time you left your home system (as other answers, they may need to send some probes to locations not to far from the target area to update their database). They set you up with a few example view points. Every time the stars look totally different. Surely this is hopeless - you won't ever recognise anything. So many images have gone back and forth you can barely remember what you're looking for.
The screen is focussed on the view towards andromeda - one of the few common waypoints you could identify with certainty. The first try with Sagittarius was hopeless, as there are even more stars in that direction and you can make almost any shape you want (besides you can't remember the shape of that one so well).
After flicking between hundreds of random search points within the target area, suddenly "the projected view to Andromeda galaxy from this place kind-of looks a little bit like Andromeda, but really distorted and with stuff missing", then the alien lets you jiggle the stick a little, and a star approaches from the right side of the screen. You try to use the star to complete the picture, but it's still badly distorted. Looking at other parts of the simulated view from this place, nothing is recognisable. Disheartened, you think it must just be a co-incidence. The alien moves to a full 360 degree projection room and moves the simulated view point back and forth along the direct line to Andromeda. The star you picked fades almost completely out of view, and whichever way the alien moves the view, it gets worse. "It's no use - it must have been a co-incidence, the rest of the sky is totally wrong". As you turn to say this, the stars whizz past to the side. The galaxy never seemed so big before, even some of the smallest movements completely change what you see. Suddenly something familiar is there, and then gone again. "Go back a bit" you scream. Suddenly there it is - not quite right, but recognisable - the most recognisable constellation of the northern hemisphere, Ursa Major. "fix on that, and move really slowly". The distortions get worse. "No, the other way". The sky starts to come into alignment. Looking back towards Andromeda, the star you'd picked is barely visible and well out of position now, but another has moved over and is now in almost the right place.
The alien reveals how lucky we got - in the whole search we'd only panned the viewpoint by less than a hundred light years. The triangulation had several thousand light years of uncertainty. Never before had you appreciated just how big the universe was.
You look again at the chart. Something is very wrong. "I don't remember a huge bright star there." The alien looks up the statistics for that star. "The simulation says this is within 1 of your light years of the simulated position. That star should have been REALLY obvious". Suddenly you realise the problem... "can you delete that star from the simulation and set the view point to exactly the position of the deleted star?". The last few distortions are removed - you are finally "home".
"I'm glad you found it, but you must have remembered something wrong" says the alien. That wasn't even supposed to be in the search area. The star you've selected only seems to be less than 26,000 of your "light years" from the galaxy centre.
(put another way, the galaxy is huge, so even with this kind of triangulation to get something approximating the right search area, you're going to need to have some way to inject some lucky fluke into the story).
[Answer]
**Condition A**
You know our star is a yellow medium sized star with two gas giants (we don't know if the aliens managed to detect Uranus and Neptune). It's closest neighboring system is trinary system. Alpha Centauri-A is similar to our Sun while Alpha Centauri-B orbits it closely is of the same type but smaller and less bright. Alpha Centauri-C is a red dwarf that orbits them at a large distance. At the moment the confirmed planets in the system may not have been detected by the aliens (no gas giants).
So the question is: how many combinations like this are you going to find in the galaxy? At the moment we can't answer this but considering G stars like ours are not that common the answer may be not that many.
Still it's a 'not that many' of more than 100 billion stars. We need to add another condition to filter them more.
Of course if the aliens' data are extremely ancient Alpha Centaury may not be our closest neighbor yet.
**Condition B**
You know that our system is not in the core of the galaxy where star density is highest.
>
> Bottom line: The sun is about 1/3 the distance from the center of the Milky Way galaxy to its outer edges. It’s located in a smaller spiral arm, between two large arms, called the Orion Arm.
> [earthsky.org](https://earthsky.org/space/does-our-sun-reside-in-a-spiral-arm-of-the-milky-way-galaxy)
>
>
>
Now, how many systems satisfy both conditions? Hopefully not many. Maybe just one.
I assume the aliens have a system to do queries easily on their star map. Also that the above two conditions are known to your character. Otherwise he went to the wrong high school.
[Answer]
Very interesting question, I hope you process it into a 7-tome opus about a searching for Earth. Something with "finding" or "founding" in name :-).
I will assume that you are in our galaxy, because there are **really** too many galaxies in our visible universe and many of them will perfectly match our rather limited knowledge of Milky Way's actual shape and your vague recollection of it. It's easy to explain away with a limited portal range anyway.
What other answers mostly forgot is the need to define to the aliens our units of measure. How long is the light year? How long is the year? And so on.
Units based on human experience, like the weight of a piece of metal in Paris or a length of Earth's meridian, were in the last decades mostly replaced with objective and independent units, but I guess you do not remember their definitions.
But never mind, you still have YOU as a measure! You probably know your height, weight and temperature with a good-enough precision to define kilogram (would it be needed), meter a kelvin. You have to also estimate your pulse as 80/min, which will give you the second and the light year.
(It would also work if you knew only US traditional units, but it would be better to remain lost than admit to the aliens that you still use them ;-))
The Sun is orbiting our galaxy's center at approximately 25000 ly, close to one side of the thin disc. You might also remember relative positions of galactic center, Magellanic clouds and the Andromeda galaxy. That would roughly show Sun's position.
You could also remember approximate shape of the orbit of the S-2 star in the galactic center, which again very roughly reveal our galactic quarter.
Observations of supernova 1987A and Kepler's supernova of 1604 would rather precisely show our position (on a circle), but as others pointed out, the aliens' world can be shifted thousands of years relative to these events, so there's no way to find out if you and them talk about the same supernovae.
Sun is a single star, yellow dwarf with a surface temperature about 5000K, 5M years old. Its closest neighbor is a ternary star at approx. 4 ly.
At the end, when you search row after row in the aliens' star system spreadsheet for the one matching above criteria, with the right amount of planets, look for the one with a note "Mostly harmless".
[Answer]
they'd have their work cut out for them. because they'd have over 10,000 stars to scan. and out of those, you'd have 200 yellow dwarfs (G type stars) to look over. as for constellations, forget it, and for good reason: the night sky will be so different 200 light years out, that anything you draw would be useless in that they'd looked totally different from their own cataloged constellations.
And there's a another factor: Year length of different planets. the year length and day and night cycles of where you'll be at will be different enough that you'd be hard pressed to try do calculations to determine the year length of different planets they find.
but there is hope, just find catalog of a yellow dwarf who's system data matches the sol system, and then have them search there again.
[Answer]
Assuming you actually are in the Milky Way (*some answers point out, you might not recognize it*)
~~You should also know that Earth is in an Arm near the edge of the Galaxy. So your potential search area is limited to the edge.~~ **Update** See comments below and other answers, humans really don't know how big the Milky Way is or how close Earth is to the edge of the Galaxy.
Assuming the Aliens have technology to pick up and isolate weak radio signals....
The Earth has a [broadcast influence](https://space.stackexchange.com/q/4062/109) of about 100 light years. This space is occupied by about 14,000 stars.
If you drop probes with a spacing of about 100 light years, and listen you should be able to pick up radio and T.V. signals, some of that will be in English a language which they can compare, using your speech as an example.
Once you have found the correct 100 Light year sphere, it should be simple enough to narrow it down to find Earth.
[Answer]
If you have a photo of Milky Way on your bedroom wall, you presumably will have gazed at it while lying in bed, dreaming of travel, and undeniably will have a "You are here" label on it somewhere.
It is to be assumed that *if* it is a genuine photograph from outside Milky Way, it will also have the Magellanic Clouds in the shot as well.
So, if you are able to look at such a photograph (or even 3-d map) with your friendly aliens, you will see exactly where we are situated in that galaxy merely by using those Magellanic clouds as navigational aids. Then it is straightforward to remember where Sol is situated with relation to the specific spiral arm, and that will narrow it down far enough for you to be able to be placed in a similar enough vicinity that in *some direction* (in front and behind) some of the constellations are vaguely recognisable. Your home lies along that axis.
Both Jack Vance (in his Demon Princes series) and Isaac Asimov (somewhere in his massive oeuvre, can't place exactly where, I'm less intimately familiar with his work) discuss exactly that question. Vance brushes it off as a technique that any vaguely competent space-traveller would have as a tool under his belt.
] |
[Question]
[
I am a vengeful scientist who crash-landed on your Earth. While I was repairing my space ship, I had to obtain nourishment by consuming organic matter, and visited a local nutrition warehouse your people call "Arby's."
I have decided that the species responsible for this perversion must perish.
Fortunately, I had a spare Axial-Tilt-Tweaker-9000 aboard my vessel. I understand that your Earth has a delicate climate that can be easily affected by tilting the planet. While I have no doubt that the device will be soon discovered and disabled by your species' caste of handsome action heroes, it should be able to alter the axial tilt of Earth by several degrees over the course of some years or decades but will stop well short of turning the Earth on its side.
How much change to the Earth's tilt, between its rotational axis and its solar orbit, would be enough to cause unimaginable disaster and suffering on this planet, and should the axial tilt be increased or decreased?
**Edited to add: This would take many years to affect the planet.**
[Answer]
The first thing I'd be worried about is how fast the change in axial tilt would happen.
If it happens in minutes or seconds, then people get thrown into walls at high velocities. The walls won't survive.
If it happens over the course of a day, there would be major tectonic stresses suddenly redistributed. Earthquakes, volcanoes, dogs and cats living together... Mass hysteria!
Even if it happened over the course of several months, there is still a huge mismatch in rotational energy, where the core is spinning in a different direction from the crust, causing huge stresses.
But, if it happens over the course of a day, it still allows for an interesting story. Some buildings might slip from their foundations, as the forces of inertia suddenly make gravity seem that "down" has shifted by a couple of degrees for several hours, but most buildings and technology would survive.
Astronomers are pissed off. Besides all of their telescopes pointing in the wrong direction, their favorite observatories that used to sit on some of the tallest and most remote mountains are sitting in active volcanic calderas.
People also can't get satellite TV unless they reposition their dishes.
And, somewhat more significant to the future: Jet airplanes would be grounded. Not because of any property of axial tilt, but because of volcanic ash and how destructive it is to jet engines.
The first *climate* effect would be the same, whether you increased or decreased axial tilt:
Volcanic winter.
Volcanic ash is pretty reflective, and doesn't hold heat very well; quite the opposite to atmospheric CO2, which doesn't reflect light but holds heat very well.
Global temperatures drop quickly. Some microclimates may warm up -- i.e., decreased turbulence would keep tropical air from mixing with air in cooler regions as much, but overall the average temperature drops quickly and significantly. (See [Little Ice Age](https://en.wikipedia.org/wiki/Little_Ice_Age "Wikipedia link to the Little Ice Age") for an example of just a few more volcanoes than usual being active over a long period of time.)
Ash doesn't stay in the air for long. Tectonic stress doesn't stay high for long when the stress is actively being relieved. This volcanic winter should only last for a decade or so.
It's likely to be followed by a volcanic summer. Ash on the ground gets wet, gets dark, and traps heat on the surface. Humans will have probably used much more fuel to warm their homes and try to plant more crops, releasing more CO2, which will now start trapping that heat.
But, the next effect depends more on which direction you tilted the axis. Is the tilt now 13 degrees or 33 degrees?
If the tilt were only 13 degrees, then seasons as we know it would greatly diminish. Areas at the equator would get much warmer. Areas near the poles would get much colder. There would be much less circulation between these regions. The tropics (which would be a much more narrow band around the equator) would see more rain, while the rest of the world would see much less. Much ecological diversity would be lost, and humans would have to struggle to adapt.
If the tilt were increased, then seasons would get far more pronounced. Deserts would get rain. Rainforests would dry up. Much ecological diversity would be lost, and humans would have to struggle to adapt.
*Note that this answer is based on an earlier version of the question, where the change of axial tilt was limited to 10 degrees, and there were no limits on how fast the change would occur.*
[Answer]
You can really cause a lot of destruction with that machine, but you know what? If you just kill everybody in the span of a week, then there will be no people suffering on Earth forever after.
If you want to maximize disaster and suffering, you want to torture rathen than to kill. So flip the planet around, 180 degrees. Seasons will be preserved. Some organic life might have to readjust to an unexpected extended summer or winter but they will be able to deal with it.
However, until the Sun becomes a red giant and swallows the Earth - which should take a few billion years - you will see people strugling with the change of direction.
Initially everybody is going to be pretty mad at GPS failing miserably. That will be a good one, but it should be fixed quickly.
Flat earthers will be pulling their hairs when Polaris is no longer the central star, but then again, who cares about them?
The best part will be people who are too proud of whatever plot of land they have been born on. They will not accept that the South is the new North (and vice-versa). There are enough of them to keep the debate of what is South and what is North going on, and heated at that, forever.
It will take centuries to clear up the nomenclature mess. There will be gnashing of teeth over NAFTA becoming SAFTA, and the whole north americans vs south americans thing, with America being in South America now. That oughta drive a lot of people crazy.
The ensuing debate between those who wish to rename the hemispheres and those who don't will confuse anyone working with geolocation, and also those who work in the fields of history, especially dealing with pre-change texts. And since being pedant is basic human nature, this talk will dominate conversations on social media and create yet another schism factor between people.
---
But if you really don't care and just want to kill rather than stun, [decreasing tilt by a degree and a half will cause an ice age](https://en.wikipedia.org/wiki/Milankovitch_cycles#Axial_tilt_(obliquity)). It may take a few years to kick in, though.
If you don't want to be economic, increase tilt to 90 degrees. If you time it right you melt the South pole and cause a flood that would put the biblibal account of Noah to shame.
[Answer]
Point the South Pole at the sun. For the next month or two there would be no sunlight in the northern hemisphere. All plants would die. (Plus it would be really cold.)
Three months after the initial shift, the Earth will have traveled 1/4 of the way around the sun. Both hemispheres would have daylight half of the day.
A month later and the South Pole is getting shorter and shorter days.
6 months after the initial tilt-change, the southern hemisphere would be in complete darkness. The month before and after that would be dark and cold too. During that time, all plant life in the southern hemisphere would die.
Sounds pretty catastrophic to me. "Handsome action heroes: the South Pole is pointing at the sun! We only have a short time to move everybody to the southern hemisphere, and 6 months to fix the axial tilt and save the planet!"
[Answer]
Nope. It would be quite annoying, but well short of "unimaginable disaster".
Decrease the tilt from 23 degrees to 13 degrees, and seasonality is decreased in the temperate zones and polar regions -- summers would be cooler and winters would be warmer. In time this would have a large impact on things like the boreal forest and forces changes to some crops in some areas, but the entire tropics and sub-tropics would be basically unaffected. Impact: definitely. Disaster: Maybe in some areas, and probably rather slow motion. Unimagiable disaster: No.
Increase the tilt to 33 degrees and seasonality is increased. Again, the tropics would be little affected while higher latitudes would be affected most. The Arctic Circle would come down to 56 degrees north latitude, so all of Scandinavia would be north of the Arctic Circle as would be Russia right down to Moscow. High latitudes would have long, brutal winters and long, probably hot summers. Impact: definitely. Disaster: definitely at high latitudes and pretty quickly. Unimaginable disaster: Still no. Quite imaginable.
[Answer]
I have honestly no idea how much more or less tilt the planet could handle, but i know that our climate is a complicated system of interactions between air and sea currents, mountain ranges, energy input and loss, the distribution of ice covered areas, etc. pp.
If you tilt the axis of earth in either direction, changes and chain reactions can be expected. But if this is enough to get to a scale of "unimaginable disaster"... i don't think so. It definitly won't trigger something like in "The Day after Tomorrow".
[Answer]
Well the most you would have to tilt would be 23.4 degrees less aka making the planet have no tilt.
This would eliminate seasons and damage almost all life.
I have no idea what the minimum is however.
] |
[Question]
[
My story takes place in a fantasy/medieval setting, that will incorporate mostly European, most specifically, French medieval inspiration. My main character is traveling from a small village, to a large city within a couple weeks time. In that time, I would like to incorporate an inn or two. The question that I've been trying to figure out, is how close were inn's typically, from one another in medieval Europe/France? I figure that there would be a few close to the city, for those who could not find lodging in town, as it is a very busy place.
[Answer]
Hate to say it varies, but...it varies.
Start with this question, just because it's a wealth of info and tangentially related.:
[In a medieval setting, how far apart should towns be?](https://worldbuilding.stackexchange.com/questions/77600/in-a-medieval-setting-how-far-apart-should-towns-be/77604#77604)
Which is all about how far apart towns should be. As to inns, you'll want to keep in mind that not all inns were...official inns.
Some of them were homes.
You'd pass by a farmer's house, ask about lodging. Sometimes the farmer would provide it, or could tell you of a farm house where people would take in travellers.
See, when not many people travel through an area, it's not actually profitable to HAVE a dedicated inn. And because Medieval times were far less populated, well...lots of these places won't be.
In larger towns and along trade routes, sure.
As far as cost, some people will be eager enough for news of the road that they will only want chores done in exchange, or entertainment.
The coaching inns that @SudoSedWinifred is citing, were more popular round between 1500-1900, way after Medieval times. There were some during the 1200s, yes, but they are more common later on.
How far apart official inns will be very much depends on how busy the route is. Absolutely they can be further than a day apart.
They'll be in large towns, they'll be in larger cities, and they will be at crossroads on a route,
>
> The inns and innkeepers of medieval England form a poorly documented and neglected group of institutions and individuals. Yet at a time of growing specialism, they were a crucial part of the economic infrastructure of the country. This study is focused on the documentation for central southern England but seeks to place this in a wider perspective. There was now a regular provision of inns in accordance with the size and importance of the towns. Inns generated substantial rent and were evidently felt to be worth considerable investment. Innkeepers were among the rich and influential members of the town. Inns played a vital role in the evolving and prospering economic, social and political life of the nation in this period. [SOURCE](https://www.tandfonline.com/doi/full/10.1080/03044181.2013.833132?needAccess=true)
>
>
>
The paper I've cited talks about how inns late Medieval inns were connected to the size and importance of a town. Know that the further back in Medieval history you go the less likely there will be official inns. Lots of different places, including monasteries provided succour for the weary traveler, for a fee. There will be plenty of tiny towns, which will only be an outpost, and might not even have an inn. If you ARE NOT travelling along a well-travelled route, like say, the one in the Canterbury Tales (which was along a sort of tourist holy route) actual inns will be rarer.
>
> The tales are presented as part of a story-telling contest by a group
> of pilgrims as they travel together on a journey from London to
> Canterbury to visit the shrine of Saint Thomas Becket at Canterbury
> Cathedral.
>
>
>
A pilgrimage route like that, which would have large groups travelling together--you can bet that that there would be places to stay A LOT more frequently than a day's walk. But whether they would be actual inns--that's going to depend on the surrounding area and population. [Many places](http://www.medievalhistories.com/medieval-inns/) just have rooms with no beds, just a common room with shelter (bring your own bedroll!) Though from about 1300 there was a boom in private rooms--even then, you might have a bunkmate, really depended on how much $$ you had. Some of the sleeping areas/halls were actually markets in the day time, and when the stalls were packed up, you just slept where you could. paying a small fee for the privilege. And some farmhouses would only take in wealthy travellers.
There were far more travellers AFTER the Black Plague hit, hence more private rooms rather than communal sleeping areas--and far more were opening because people saw travellers looking for a place and finding none, which meant there was a demand. (Though not quite so high as many of them hoped!)
So, in short, the frequency of inns is all about location! As in how many people tend to travel in an area, which is influenced both by time and social factors, like post-plague created a labor shortage that lead to more travel, plus, religion (read:tourism), and trade. On the moors in Scotland for instance--not so many.
On your country road, there might not be any actual inns, but once you get on the trade route there could be lodgings, and the quality and size of those will vary. Don't expect most to be as large as our modern hotels. And expect that some meals will be included in the lodging.
[Answer]
It would be good to analyse old maps of cities and routes, particularly in Europe. Lodgings were typically dispersed along trade routes, as economically and practically these are the ideal locations for them. As in medieval era merchants would normally transport goods from port cities overland to inland cities, they would traverse well-defined and planned routes, stopping for supplies usually on a regular basis.
Along the Silk Route, it is well documented that many 'Trading Posts' were placed several days ride (2-3) apart throughout the route from France, Italy through to Northern India, established almost a thousand years earlier in Roman times when silk was an exotic commodity within the Empire and extant till shipping became the main form of freight.
If your question relates to a location of an Inn in a medieval city, you could look at the typical evolution within a city. Again, origins in European cities are typically derived from ancient Roman cities, where typically they are located at cross roads, with central squares bounded by markets, institutional facilities, religious and military structures, with residential structures surrounding these. All medieval cities have this basic structure thanks to the Romans, Inns would be located usually at intersections surrounding squares and 'arterial streets'. It is not usual to have structures a significant distance from a main square, besides aristocratic villas or farms, for both defensive and economic reasons, until the advent of gunpowder and cannons, where development began to become more dispersed (but only in new forts and newly formed towns, many cities still retained their ancient Roman roots and were of a compact nature).
[Answer]
Going on spec here, putting together snippits from an article in Scientific American on the distribution of sizes in towns and market towns, and a CBC ideas show on alcohol in the middle ages.
Villages generally were no more than 2 hours walk apart, unless there was land that was difficult to use along the way. Reason: An hour is about all the commute people will tolerate. When it gets more than that, it's worth while to make a permanent place to stay.
Small beer (running 1-2% alcohol) was the common beverage. The alcohol killed most harmful bacteria. *commenter points out it was likely the act of boiling the water used to brew that made beer safer to drink. A check confirms that 2% alcohol is not an effective bactericide*
So unless the town was *really* tiny it would have a brewery. People could come by with a pail to get a pail of beer to take home. While a much later time, the behaviour is described in the coal towns in wales in "How Green Was my valley." You can also the at the beer ration given to the royal navy.
A brewery makes a good place for people to meet, to socialize, to drink. It's an easy extension for a brewery to offer rooms for the occasional traveler. It also makes a logical place for a traveller to get information. A pub keeper would be up on all the local news and most of the travelling news.
On the other hand, to become an inn would require regular traffic. For a small town, say under 500 people this would likely be more or less mid town. As the towns got larger, an inn is more likely to on the main road at one end or another, as is any business that has more than one or two horses. You want ready access to pasture, and shorter haulage distances for hay and manure.
The physical size of the town is very era and culture dependent. In an orderly culture, where the king's writ is enforced, towns could afford to sprawl. In more chaotic time and place, towns would be walled and as small as possible to make it reasonable to defend the walls. In these places, peasants lived in town. A house by itself was too dangerous. This would mean 1 or 2 room homes, often with a shared wall.
This doesn't give you numbers.
Ok. Let's take a village as having a radius of 3 miles. This gives it an area of roughly 27 square miles. Let's suppose that half is farmable, the rest a mix of woodlot and pasture. 14 square miles of land = 14 \* 640 = 9000 acres. It took about an acre to feed someone for a year. A peasant would likely farm 4-6 acres. So our town in principle supports 5 to 7 thousand people. (Assuming around 20% of the food is taxed away) This is large enough to support multiple pubs.
So on that basis in well settled country I would expect to pass several inns a day.
Once you get into rough country, the population density drops. A town in a forest is going to have to import nearly all it's food, and export lumber or charcoal. This sort of economy is not common. A village on the edge of hte forest with a mixed economy is more likely, possibly with camps in the woods where men would work during the week. Still at this remove, I'm betting on an inn or something similar no more than a day apart.
The forest made northern Europe scary. Soils were heavy, and were hard to work with the mediteranean scratch plough. With not much agriculture there wasn't much in the way of civilization. Go reread the Grimm's fairytales.
One of the ways to get an estimate with a bit more meat on it would be to check through parish records of the time. Often they would record the occupation.
Another source would be a translation of the Doomsday Book, the comprehensive survey of England commissioned by the Norman invaders.
[Answer]
Spacing them every "one day's journey" (20 miles for walking, 30 miles for riding) is reasonable.
Busy roads will have more (or larger) inns, and crossroads (around which market towns usually develop) will have even more.
] |
[Question]
[
What environmental effects (if any) would ever cause blue to be a colour that a plant would choose as an evolutionary advantage?
Bonus:
I'm looking for light blue plants as a preference.
EDIT:
Thank you for all the answers about how plants are capable of looking blue using Phycocyanin, or variants of Chlorophyll, but I'm looking to see why a plant might choose this evolutionary path.
[Answer]
Plants would be blue if their photosynthesis were based on [phycocyanin](https://en.wikipedia.org/wiki/Phycocyanin) instead of chlorophyll. Since there are organisms on earth that use this, it's not entirely implausible that it could be used also by higher plants in an alternate world.
So what environmental effects could cause phycocyanin instead of chlorophyll to be the dominant photosynthesis substance?
Looking at the chemical formula, phycocyanin only consists of carbon, oxygen, nitrogen and hydrogen, substances you find in almost every organic material. On the other hand, Chlorophyll contains a magnesium ion. So one reason for plants photosynthesis being phycocyanin based could be if the world happens to have no or very little available magnesium.
Another possibility, which was already mentioned in other answers, is if the central star has its maximum in the red part of the spectrum (for example, a red dwarf — somehow in all my answers I seem to end up finding you need a red dwarf :-)), so blue absorption would not be very advantageous. The same may be true if the atmosphere has a strong absorption of blue light, so not much of the blue light of the star reaches the surface.
Yet another point mentioned in the Wikipedia article is the heat resistance of phycocyanin. So if your world is very hot, that also could be a factor for dominance of phycocyanin.
[Answer]
The chlorophyll within the plants would have to be adapted to absorb the Green spectrum rather than the Blue, on earth plants absorb the Blue & Red spectrum and reject the Green. This causes them to appear Green in colour.
If the chlorophyll were to change in some way, or a different molecule or technique was used by the plants to convert sunlight to usable energy then the colours they appear will change.
Far more depth and explanation (far better than my shoddy attempt) is given here:
<http://www.livescience.com/1398-early-earth-purple-study-suggests.html>
>
> The earliest life on Earth might have been just as purple as it is
> green today, a scientist claims.
>
>
> Ancient microbes might have used a molecule other than chlorophyll to
> harness the Sun's rays, one that gave the organisms a violet hue.
>
>
> Chlorophyll, the main photosynthetic pigment of plants, absorbs mainly
> blue and red wavelengths from the Sun and reflects green ones, and it
> is this reflected light that gives plants their leafy color. This fact
> puzzles some biologists because the sun transmits most of its energy
> in the green part of the visible spectrum.
>
>
>
**Edit:** [Celtschk's answer](https://worldbuilding.stackexchange.com/a/723/322) gives the real-life alternative of [Phycocyanin](https://en.wikipedia.org/wiki/Phycocyanin) to Chlorophyll. This gives a slight, yet visible blue-green tint to [Cyanobacteria](https://en.wikipedia.org/wiki/Cyanobacteria) (blue-green algae) which it is found in.
[Answer]
Blue would actually be a better colour for terrestrial plants to be than green, *if* there was a photosynthetic pigment that colour that approached that of chlorophyll in efficiency, as the sun's peak light output is in the green part of the spectrum, and a blue pigment would not reflect as much as a green pigment would.
Also, if the sun your proposed planet orbited was redder, a blue photosynthetic pigment would be even more useful, as redder stars emit less blue light than our own sun.
There are a number of different photosynthetic pigments that have evolved on Earth, some reds, some greens, and one purple. Not all of these pigments/proteins produce oxygen as a photosynthetic by-product, some produce hydrogen sulfide (H2S)
There is no reason why a blue photosynthetic pigment might not occur, however it is more likely to be a dark blue or a mid blue than a light blue, as darker colours absorb more energy. However, purple at least has the advantage of having already been done.
[Answer]
Having less blue light available has been mentioned in several answers here. While that may lead to plants that absorb other colours and reflect the blue, they would not necessarily appear blue to the eye since there is so little blue in the environment. This could just make them appear black, or at best dark blue, whereas the question asks for light blue.
# Alternatives to chlorophyll
Very few photosynthetic chemicals have been discovered by organisms on Earth. This suggests that the colours we see are more due to what chemical happened to be found first, rather than the natural selection of the best colour from a large number of pigments. Even in an environment identical to Earth's, different colours may emerge just by chance.
# Additional colour beyond photosynthesis
An environment that actively favours light blue may not be one that forces a change from chlorophyll, but simply one that demands that leaves have other sources of colour apart from photosynthetic pigments. This is likely since the question specifies **light** blue, which means not only reflecting blue light but also reflecting a proportion of all the other colours too (just reflecting blue light would lead to a mid blue).
An environment may encourage other pigments in addition to the photosynthetic pigment. If these other pigments are more reflective than the photosynthetic pigment and present in greater concentration, then their colour may dominate. For example, on a planet with harsh radiation plants may need to have pigments that reflect away most of the light to avoid damage, only using what little light gets through these protective pigments in order to photosynthesize. This would give the leaves a pale colour due to reflecting most light, and the particular pigment or pigments used to do this may result in this being pale blue. A peak at the blue part of the spectrum of the incoming light would provide a selective pressure to produce more of the pigments that reflect more blue light, to give the most protection there. The result would be pale blue leaves. This could also lead to pale blue trunk and branches, and quite possibly pale blue animals too.
# Other methods of extracting energy from light
Photosynthesis is used by plants on Earth to extract energy from light using chemical means. On another planet, this might not be practical, or it might simply not happen to evolve. In that case, plants may evolve that use physical means rather than chemical - perhaps using the light to induce a temperature difference along the trunk which can then be used to drive electric current to power chemical reactions (roughly the opposite of the process occurring in the nerve cells of animals).
Such plants may have a very long dark trunk to absorb as much light as possible, then branching out at the top into a canopy of very light coloured leaves to reflect as much light as possible. This, combined with roots seeking out warmer earth below, would produce a temperature gradient sufficient to at least supplement its energy requirements during parts of the year, and possibly provide all of its energy.
[Answer]
The reason most plants are green on Earth is because their leaves contain a large amount of a chemical called chlorophyll which is used in photosynthesis (creating energy and oxygen from sunlight).
Many scientists believe chlorophyll is green because it absorbs both the red and the blue areas of the spectrum and reflects the green regions. If your sun produced less blue light then it's likely that your plants would evolve to feed off the red/green parts of the spectrum instead. The result would be that blue light is reflected for us to see.
Another alternative is to forgo photosynthesis altogether, after all on an alien world plants may behave very differently. Maybe they take nitrogen straight out of the atmosphere using a blue coloured chemical instead?
[Answer]
If the atmosphere preferentially absorbs blue light (due to some gasses present) then there would be no advantage for leaves to absorb it themselves and in trying to efficiently gather the radiation that does reach them they may well end up reflecting blue light.
Equally if the sun didn't emit much blue light (for example a red giant star) then you might get a similar result.
You need the light reaching the plant to have the characteristics that make blue the most efficient color for absorbing the light and making use of it.
Alternatively if something in the environment made the techniques plants use here on earth not viable (for example a chemical that damages chlorophyll present in the air) then alternative techniques would need to evolve, and those might result in blue leaves.
[Answer]
The primary reason as to why plants are green is because it strikes a balance between not having enough energy to photosynthesis and denaturing its own enzymes by having too much heat. For there to be a shift in what colours are reflected away, part of this equation would need to change, probably the heat. If the world was colder, or for some reason plants were much more efficient at dissipating heat then this equation would change as they would be able to deal with more heat. There would need to be very specific conditions in place or they might well be black rather than blue, and obviously these plants would need to be able to survive at cold temperatures.
[Answer]
A plant can use methylene blue and one of many blue chemicals to protect itself from an environmental stress, chemical, physical biological.
There are very many pigments and oxidated metals that are blue, In the deep ocean, only blue light exists so that may have an effect on a photosynthesis, and the same may be true in planets where the useful wavelengths cause blue to be reflected.
If very strong radiation exists on the planet and the plant develops a particular protection to UV/Xrays from a nearby astronomical body or something, certain light filtering chemistry may cause the plant to reflect blue.
If for some reason the animals percieve differently due to a copper based animal life form, a plant can be blue in order to use it's symbiosis/commensal animals the same as blue flowers. Blue is one of the most common flower color due to the vision of insects.
There are many blue oxydates and pigments and refraction structures in cheratin and similar, crab blood is blue, and plants can be blue via many chemical reactions, i don't know chemistry well enough to list some, if i could find a list of blue chemical reactions and better still of blue oxydates then i'd find it.
] |
[Question]
[
A futuristic entrepreneur wants to start a cruise line company and needs to build a cruise ship that will not only float on a gas giant, but be habitable throughout a 7 day trip (for the uber-rich of course).
**What sort of ship would need to be built to survive a week on a gas giant?**
Ideally, the ship would float on its own, due to buoyant forces.
In regards to the level of technology required: it should be *as advanced as it needs to be* in order to accomplish this goal - i.e. hand-wavey technology is allowed if there are no other options.
[Answer]
# Analyzing Jupiter
[](https://i.stack.imgur.com/G3FYP.png)
First off, since [Jupiter](https://en.wikipedia.org/wiki/Atmosphere_of_Jupiter) doesn't have a surface, the 1 bar pressure altitude is commonly referred to as the surface. Surface temp ([from a NASA fact sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/jupiterfact.html)) is, in that case, around 165 K; cold but not cold enough that you couldn't insulate it trivially. So in this region, pressure and temperature are not a major concern. At this altitude and nearby you will get clouds of ammonium hydrosulfide, with water clouds also in denser areas below. These aren't really a problem, either.
Instead, what you need to worry about is the 100 m/s winds at this altitude. The wind speeds do vary by zone, so there are areas between bands where wind speed is near zero. A graph of wind speed by latitude illustrates this.
[](https://i.stack.imgur.com/hsWqY.png)
These wind speeds are in the [jets](https://en.wikipedia.org/wiki/Atmosphere_of_Jupiter#Zones,_belts_and_jets), in the 0.7-1 bar region all the way down to at least 22 bar, which is as far as the Galileo probe got to check on them.
So a better solution might be to fly higher, above the clouds. At about the 0.1 bar zone (or 10$^4$ Pa on the top chart; 50 km altitude above the 1 bar level), the winds have mostly decayed away (they decay away in 3 [scale heights](https://en.wikipedia.org/wiki/Scale_height), and a scale height is 27 km on Jupiter), and force on a craft from wind will be reduced by a factor of 10. Temperature is even lower at about 112 K, but with low air pressure and little wind, there won't be too much heat loss. Insulation should again be trivial.
So now we can handle pressure, temperature, and winds at this altitude, all that remains is to deal with the gravity. With low air pressure, floating will then be hard. In fact, it will be close to impossible. The atmosphere of Jupiter is primarily Hydrogen and Helium in the first place, meaning that hydrogen balloons won't float like they do on Earth. Even if you kept your balloon's gas filled envelope at a very high temperature, the density difference would be only marginal with the surrounding air. You could lower the balloon's envelop pressure to drop density further, but then you would need a rigid envelope, further increasing your required structural mass and making the balloon less efficient still.
More rigorously, the density of Jupiter's atmosphere at an altitude of 1 bar is 0.16 kg/m$^3$. If we can hold our balloon envelope at *vaccuum*, then we can lift 32 tons of mass per Hindenburg of volume. Unfortunately, that isn't really that much; the Hindenburg itself was more like 230 tons of mass. At 1 bar of pressure, the forces on an envelope held at vacuum will be tremendous, not to mention the shear forces from 100 m/s winds.
Finally, the biggest problem with your cruise ship idea is that your passengers will be crushed by the gravity. With gravity around 25 m/s$^2$, it will be much higher than on Earth. Not only will that make already-nearly-impossible floating even harder, it will probably kill all your passengers.
# Other Gas giants
[](https://i.stack.imgur.com/jMBsN.jpg)
[Saturn's](https://nssdc.gsfc.nasa.gov/planetary/factsheet/saturnfact.html) atmosphere is similar to Jupiter's. In fact, the density at the 1 bar level is slightly higher (0.19 kg/m$^3$), despite its lower surface gravity (1.06$g$). On the other hand, its scale height is larger (52 km) and wind speeds are much higher, up to 400 m/s at the equator. Also, as you can see in its graph, its 'surface' is the 0.1 bar level, not 1 bar. This means that you will see the very high wind speeds at that lower pressure level. Thus, even floating at high altitudes with nearly zero lift, you still get buffeted by extremely strong winds.
Assuming you can survive the high winds at the 0.1 bar level, given the density of the atmosphere, a spherical balloon envelope 1 km in diameter will have a volume of about 0.5 km$^3$ and a lift of 9500 tons; enough for a tourist vessel. A full on modern cruise ship of 100,000 tons would require a spherical balloon of a little over 2 km diameter.
The other gas giants are considerably more iffy regarding data; Jupiter and Saturn have had the attention of Galileo and Cassini, respectively, for many years. Uranus and Neptune have not. NASA's [Uranus](https://nssdc.gsfc.nasa.gov/planetary/factsheet/uranusfact.html) fact sheet gives a very promising atmospheric density of 0.42 kg/m$^3$. However, wind speeds are not well known and could be up to 250 m/s. If there are lower winds speeds at this altitude, then this would decrease the volume of vacuum needed by a factor of 2. However, this really only reduces the speed at which you must wave your hands to make this a reality.
# Conclusion: Wave many hands
On a gas giant with Jupiter's gravity, the only way to save your passengers is with some magical gravity canceling device. I would assume that having such a device would then make floating your ship trivial. But without hand-wavey solutions, not only can you not float in Jupiter's atmosphere, you will kill your human passengers trying to do so.
Other gas giants are less magic-requiring, in that surface gravity will be close enough to Earth's to not kill your passengers. However, the problems with floating in an atmosphere that is already made of helium, the least dense element, remain. Even at vacuum, you have almost no lift. The solution is materials of indeterminately high strength, in order to hold a (very, very) large envelope at vacuum against atmospheric pressure, while not disintegrating in the high winds. Just to be clear, given the forces involved in holding a cubic kilometer or so at vacuum against 1 bar pressure, this is nearly as hand-wavey as a gravity canceling device.
In fact, the larger the better. If you want to ensure the passenger's comfort, you will need the most mass and inertia in your balloon as possible to keep the winds from buffeting them uncomfortably. That means, you will need a vacuum chamber kilometers across; like a mini-moon floating in a Saturnian sky.
[Answer]
Let's look at some key [Jovian atmospheric characteristics](https://nssdc.gsfc.nasa.gov/planetary/factsheet/jupiterfact.html):
* **Density at $P=1\text{ bar}$ (i.e. the surface):** $\rho\_J=0.16\text{ kg m}^{-3}$
* **Temperature at $P=1\text{ bar}$:** $T=165\text{ K}$
* **Mean molecular weight:** $\mu=2.22$
* **Primary atmospheric constituents:** H (89.8%), He (10.2%)
In other words, if you want to float close to the surface, you're in a cold, gaseous region with a low density. This isn't great; according to [Archimedes' principle](https://en.wikipedia.org/wiki/Archimedes%27_principle), any lifting gas you use must be less dense than the medium surrounding it. The atmosphere outside is already not too dense, which is problematic.
## 1. Float low
High in Jupiter's atmosphere, there's a smooth transition to the interplanetary medium, where you see a lot more hydrogen. Lower, near (and below) $P=1\text{ bar}$, $\mu$ is higher and $\rho$ is also higher. This means that your lifting gas doesn't have to be as lightweight as if you were trying to float near the top of the atmosphere.
As [kingledion's chart](https://i.stack.imgur.com/G3FYP.png) shows, temperature is roughly constant from $P=10^{3}\text{ bars}$ to $P=10^0\text{ bars}$ - i.e. right below the "surface" of Jupiter. However, at the surface, it rapidly increases, as density and pressure rapidly decrease. I would aim for this region - at the surface or a bit below it. You'll probably be stuck in the same temperature range, $150\text{ K}$ to $200\text{ K}$, and pressure is the main difference.
## 2. Don't go for a vacuum airship.
We already know that [that sort of thing is hard on Earth](https://worldbuilding.stackexchange.com/a/11370/627). In the regions we're considering, the outside pressure is going to be even stronger. Sure, you can *maybe* mitigate that with whatever tech you've developed by the time humans can get to Jupiter, but you can only handwave away so much. It just won't work at this part of Jupiter.
Instead, use something like heated hydrogen! This is why I like the low-temperature region of the planet. The surrounding gas will have a higher density and a lower temperature, and so any particular lifting gas at a certain temperature will be more effective. Obviously, hydrogen is flammable, but hey, it's cheaper than helium, and if you're safe, maybe things won't go so poorly.
Let's say the ship is designed like a Zeppelin, with a chamber of gas of volume $V\_g$ and a cabin of volume $V\_c$. The mass of the gas is $m\_g$ and the mass of the cabin is $m\_c$. We then need, for the ship to float at equilibrium,
$$F\_{\text{buoyant}}=(m\_g+m\_c)g=\rho\_J(V\_g+V\_c)g=F\_{\text{gravity}}$$
where $\rho\_J$ is again the atmospheric density of Jupiter at $P=1\text{ bar}$, and $g$ is Jupiter's surface gravity. Now, $m\_g=\rho\_gV\_g$, where $\rho\_g$ is the density of the gas. Therefore,
$$(\rho\_gV\_g+m\_c)g=\rho\_J(V\_g+V\_c)g$$
Rearranging, cancelling and solving for $\rho\_g$, we find
$$\rho\_g=\rho\_J\left(1+\frac{V\_c}{V\_g}\right)-\frac{m\_c}{V\_g}$$
Given that $V\_c\ll V\_g$, we can appxoximate this as
$$\rho\_g\approx\rho\_J-\frac{m\_c}{V\_g}$$
Choose your cabin mas wisely, and adjust the other two parameters as you desire. For the [*Hindenburg*](https://en.wikipedia.org/wiki/LZ_129_Hindenburg), for instance, $V\_g\approx200,000\text{ m}^3$. This actually allows us to have a comfortable cabin mass, if we're willing to raise the temperature enough inside. You'd be able to look for something in the vicinity of a couple tens of tons. Not a lot, but enough.
Let's use the [ideal gas law](https://en.wikipedia.org/wiki/Ideal_gas_law) for the inside of the gas sac. Assume $p=1\text{ bar}$ (roughly) and $\rho\_g\approx0.10\text{ kg m}^{-3}$. Then we have
$$P=\rho\_g \frac{k\_b}{\mu\_gm\_u}T\_g$$
where $k\_B$ is the Boltzmann constant, $\mu\_g\approx1$ is the mean molecular weight of the gas, and $m\_u$ is one atomic mass unit. I find that $T\_g\approx121\text{ K}$. We can afford to have a higher $\rho\_g$, too, so the hydrogen gas can be a bit hotter. Now, this means we must have a smaller cabin mass, but still.
## 3. Insulate well
It's all very well and good having a warm bubble in a cold atmosphere, but if there's heat transfer, your ship will soon freeze. I've continued to do reading on possible materials without much luck (although I daresay that someone else probably knows enough to find something good), but then again, I'm not great at materials science.
I do think that you'll want to have some sort of composite skin on your airship. You need it to be able to survive pressures both a bit higher and lower than on Earth - while still keeping the hydrogen gas inside - as well as withstanding some pretty cold conditions. Neither of these are overly problematic; there are plenty of materials that can do this.
The problem is, quite simple, one of weight. Anything that flies - and this ship *will* fly, in a sense - needs to take weight into account. I've already done this when considering the mass of the crew cabin. However, I'm a lot more concerned about covering the envelope with something that's strong, lightweight, *and* a good thermal insulator.
[Answer]
Although we could make a balloon, or even a vast construct like Buckmaster Fuller's "[Cloud 9](https://infogalactic.com/info/Cloud_Nine_(tensegrity_sphere))", one issue which you haven't though of is how are you going to board and disembark?
[](https://i.stack.imgur.com/CVuwp.jpg)
*Cloud Nine (tensegrity sphere). For Earthly flight, you would need a sphere almost a kilometre in diameter as a minimum*
You will be blasting off through the atmosphere of a gas giant, and need some pretty incredible rocket power to overcome the gravity as well. In essence, you would need a spaceship to enter the atmosphere, deploy a balloon for a week, then blast off (probably through the balloon) to escape. This is the sort of model proposed by the British Interplanetary Society when they worked on their "[Project Daedalus](https://infogalactic.com/info/Project_Daedalus)" interstellar probe, with [harvesters](https://www.centauri-dreams.org/?p=18193) in the atmosphere of Jupiter gathering 3He for the fusion reactor.
[](https://i.stack.imgur.com/DWvZf.jpg)
*Daedalus in orbit*
[](https://i.stack.imgur.com/eVbsZ.jpg)
*Instead of the harvester under the balloon, you have the spaceship*
For people aboard, it will be rather uncomfortable, since the spacecraft will need to mass as little as possible, yet still require massive radiation shielding, making the interior cramped. As well, a nuclear reactor or fusion reactor will need to be running constantly to deliver heat energy to the balloon envelope, and the ship will probably also be running a compressor and liquifier in order to build up a supply of reaction mass to blast back into orbit (in this case, you need thrust more than ISP). So there will be lots of background noise, in addition to any noises the balloons cables are making in the high winds.
So while it certainly will be an adventure cruise, it will be the sort of adventure cruise only very dedicated people will be willing to take.
[Answer]
Could a ship be made to survive a week inside Jupiter's atmosphere? Certainly.
There is nothing particularly terrible [there](https://en.wikipedia.org/wiki/Atmosphere_of_Jupiter), hydrogen and helium starting sparse and cold and getting denser and warmer as you go in, no problem for a controlled entry and decent. You can be nearly 1000km in before you get to Earth pressures or temperatures and reach some clouds of other gases. It would be technically challenging to be buoyant in mostly hydrogen, but perhaps a rigid vacuum chamber could be handwaved light enough.
There are big storms there, thousands of km across (not counting the stable one bigger than earth) and 100km tall, which can move hundreds of km per hour, but they seem to mostly stay in belts so could be avoided.
Could humans be happy during that week? Less so.
The gravity in clouds is about 2.5 times that of Earth. That is known to be survivable, but it would be a hassle.
[Answer]
Many other answers have already covered the dangers associated with Jupiter-like Gas Giants. In this answer I'll endeavour to suggest a few things that might make engineering the existence of these flights more viable.
1. **Engineer your Gas Giant Differently:** Most Gas Giants are made mostly of Helium and Hydrogen. This is a problem, as other answers have discussed, because they are the two lightest chemical elements known to man. However, if you had an unusual or constructed Gas Giant made mostly of Xenon and Neon for example, lifting gasses would be far more effective.
2. **Engineer Your Cruise Vehicle Differently:** Buoyancy may not be powerful enough to keep "afloat" in most Gas Giants but other methods of aeronautics also still work. Lifting bodies like wings are viable, if less effective, in these environments. Also possible in this environment are jets and propellers. They are also less effective due to the dense atmosphere but this can be mitigated with speculative engineering (not speculative science). If you make your intakes very large and have the technology for the few particles going thorough your engine to exit at a very high speed then that will offset the lack of atmosphere. Also, since the atmosphere of Jupiter is contains a number of Hydrocarbons and even Space Shuttle Fuel (Hydrazine), it may be possible to get the air flowing through the engine to a high enough temperature and pressure to ignite them. By combining all three of these ideas you can imagine a huge B2 Bomber shaped thing with large ducted jets built flush into the fuselage. If you fill most of the wings with low pressure Hydrogen/Helium and build your radiators inside the wings so that the waste heat from your ship heats up the lifting gas, you may well be on to a winner.
[Answer]
I am thinking about motorless airplanes. In good weather a man can fly indefinitely one (or until one can tolerate not going to the toilet).
I think they could have a spaceship with wings and and advanced AI that can fly it. People could be floating in water to feel better in the high gravity (or you can go to a giant with lower gravity).
The atmosphere is full of hydrogen so they developed an engine that feeds on it to accelerate ship back to orbit. Can be similar to the [bussard ramjet](https://en.wikipedia.org/wiki/Bussard_ramjet).
Credits to [this answer](https://space.stackexchange.com/questions/5387/can-we-use-interstellar-hydrogen-as-a-fuel-for-interstellar-travel).
[Answer]
I'm not sure how much help this is to you, but Clarke played with this idea in one of his stories:
<https://en.wikipedia.org/wiki/A_Meeting_with_Medusa> (Spoilers)
IIRC, he uses something more like a hot-air balloon than a blimp, and uses 'hot-hydrogen' (I think hydrogen-plasma?) to lift it.
The protagonist is an intrepid explorer, not a tourist, and it's revealed at the end of the story that
>
> he's actually a cyborg due to an earlier accident
>
>
>
which might mitigate the high gravity issue others have raised.
] |
[Question]
[
I'm creating a game that can grow to an enormous extent, basically can be played with 2 or more and every one represents a nation. Everyone starts with a small castle, a small village and a small army and builds their way up to huge castles and armies, and the winner is the last one left.
The game is almost finished (it's based in paper sheets because people draw how their castle, army village, etc appears), but the only things it's missing is currency.
I don't know anything about how currency worked during medieval times, and I have no clue how to apply currency to my game. For example, how much should a new castle wall or 5 catapults cost? I'm pretty clueless about the economics and I'm hoping someone knows the solution to my problem.
[Answer]
This [Link](http://medieval.ucdavis.edu/120D/Money.html) has the most info I have seen on the subject.
Unsure how useful it is to a game scenario though. Basically it lists common products and rough prices for them. But most things were made as needed rather than bought back in those days. So an army would probably have its own engineers to build catapults, so I would think time and availability of wood, sinew or whatever they used would be a more logical way of figuring it.
Probably most things would be the same: you get people with the skills to build whatever it is and then they build it from whatever is in the surrounding environment. Unless you get fancy and import marble or something.
Similar to how Age of Empires games work. It's all about resources rather than just gold.
[Answer]
Depends on many things. However, for much of the middle ages, manpower was power, and thus food was a de facto currency. It would be the one universal thing to trade.
[Answer]
Kilisi seems to have already given you a great source for comparative pricing. [Here's another](http://tinybatman.com/add/library/medieval_price_comparison.htm) that's less scholarly but aimed at giving general ideas for game purposes, while still being more realistic than the just-gameplay idea @Mormacil proposed that causes such misinformation in one of the few places most people actually learn about history.
Now, as far as the title of the post goes, I'll just address some ideas for names. It's standard to just say **gold** or **gp** ("gold pieces") in many games but if you're going to be generic, go the Paradox route and just use a basic symbol like • or ¤. (The East Asian 元 ["yuan", "yen", "wan"] and Monglian *tögrög* are even *named* "round things", although that doesn't work very well in English except as a generic **coin**.)
Historically, gold is gold. There are a few currencies whose names are based on it like the *gulder* and *złoty* (and a few others like the *đồng* based on other metals like bronze), but for the most part the money had to be a *weight* or *unit* of precious metal: *pound*, *libra*, *livre*, *peso* were all a **pound** and the **mark** half of one; the Mideastern **shekel**, Thai *baht*, and East Asian **兩** ("tael") were units nearer an ounce; the Greek and Roman **talents** were about half a hundredweight. Every one of those was based on *silver* instead of gold since it was more abundant and useful. If you wanted to reference that but not just say *silver*, you could call your currency **argent**. (A few other currencies were based on weights of other items, like the Japanese *koku* being a double-hwt of rice.)
In medieval settings, there were two other ways to come up with names for money.
Some coins were known for their origin. *Bezants* came from *Byzantium*, **florins** from *Florence*, and *guineas* originally derived their gold from the Guinea coast of Africa. You could just use a clipped adjective based on a mercantile location within your game world, something equivalent to a "Venit", "Yorky", or "Shang".
Others are adjectives based on the shape or design of the coin. The *groats* were fat, the *eagles* had eagles, the **crowns** and *kroner* had crowns, the *sovereigns* had kings, the *laurel* had the king in a wreath, &c. You could put pretty much any design on a token you liked and just come up with a name for it: a "dragon", a "shark", a "shield", whathaveyou.
[Answer]
I think we would have to know a lot more about your game before we could give any specific rules.
Firstly it sounds like you don't want to make it too realistic...otherwise you could decide "Hey, I *could* pay these workers to dig me a trench...but how about I just round them up and force them." or some similar method that got medieval kings around these problems.
As such this may belong more in game-rules building than a worldbuilding site.
My suggestion (as game building) would be to try to gauge how much money someone might have at a certain point in the game, you don't want someone lining their borders with huge castles. What are the hit/attack points of each? If it takes ten catapults to take down a castle but a castle costs 100 times more then you can hit the opposition pretty hard in the economy if they build a castle and you pop in and knock it down.
Several play throughs is the best tactic. You'll notice annoying tactics arise when people don't play your game as you imagined and then want to change the rules as you go along.
[Answer]
Perhaps a combination of turns, resources and currency would complicate but enhance the game. This is my example -- not cut in stone. Each turn gains you a set number of men to build or be trained for the military, and a set amount of currency. You must mine stone or metal, it takes turns to plant and harvest, and things take a set amount to do. You could collect coin instead of men, or men instead of coin, too. Players can trade as well -- but men, coin or resources are each worth a set amount. (ex: 2 coin = 1 man = 100 stone, 4 metal, 10 food.)
If you use grid paper -- then each square costs or requires a set thing "X" number of men, "X" number of resources, "X" number of coins. You'd need tokens to represent these things and a banker to dole out and collect coin at each turn. You need a balance of crops, plus men, plus resources and coin to do anything, but the combinations are pretty broad. You can't have a hundred men and the smallest castle, there's a set number per grid -- so it's all a balancing act. (The banker is at a disadvantage because they can't strategize between turns as easily, so maybe they get paid for this task.)
Call the currency 'gold', or 'silver', or 'coin'. It doesn't matter as long as you don't make it too complicated. Coin and half coins are the only things available. Or coin and 10 coin piece. Just keep it simple.
[Answer]
In Medieval Europe, money was gold, and gold was money. We're used to coins today being worth more than the metals that make them up, and that the value that they're traded for is based on what the government says they're worth. In the past, a gold coin is worth it's weight in gold, no more, no less. The purpose of minting coins is to give a guarantee that the gold hasn't been adulterated with other metals - the king's face is punched into the coin to give you his word that this coin is authentic gold. This is why you can use your kingdom's coins in the neighbouring kingdom's markets, although there is probably only so far you can go before the merchants start to refuse accepting your coins on the grounds they don't recognise your king anymore.
Something else to consider however about the medieval economy was that most people hardly ever dealt with any sort of currency. If you are a peasant working on your lord's land, he doesn't exactly "pay" you. You work his land and in return he allows you to live on it, he'll let you keep some of the food you produce, and he'll assemble an army to defend you from invaders. Lords themselves will have treasuries, but most of their economic relationships are based on barter (direct trading of resource for resource) or fealty (providing tribute to a more senior lord in exchange for protection and legitimacy).
[Answer]
Inspired by history and stories, here's an idea that may be too complicated:
Each player issues their own currency, and the value of each currency goes up and down based on the perception of their value. They're each pegged against a base currency, such as "gold" or "production", but you don't get to hold onto that. Each player starts with 100 of their own currency, but during the game may hold money in all of currencies.
So if one of your players was playing Florence, then the Florin might be worth 9 gold one turn, but only 7 gold the next. Another player, playing Byzantium, happens to have a lot of their money in Florins, so the change in Florence's fortunes affects them. They need to shore up Florence long enough to trade their Florins for something else - but only if another player is willing to accept those Florins.
This would really only work with 4 or more players, and the mechanics could get pretty complicated.
[Answer]
In terms of how much it costs to build a castle, the National Archives at Kew in the UK holds records from the Medieval period.
There are quite detailed accounts in those archives for building some of the Royal castles particularly those of King Edward the First in Wales. According to the Welsh Government Conwy Castle cost £15000 to build in 1283.
<https://cadw.gov.wales/daysout/conwycastle/?lang=en>
This according to the National Archives equates to £10,411,041.
<http://www.nationalarchives.gov.uk/currency-converter/#currency-result>
[Answer]
While Kilisi nailed the answer perfectly for how to design an accurate medeville economy, game design often suffers from too much accuracy.
The first thing you want to consider is that this is a board game. Board games are typically not like video games in that you can't expect your players to just log-on whenever, save their progress, then come back later. Players will want a game that can be played through start-to-finish in 1-4 hours. Your economy will need to be simple enough to support this kind of fast play through model.
For this you want to consider how much economy is the point of the game. If your combat system is quick and simple, then a complex economy that deals with multiple resources, production bonuses, etc will become the game. If combat and carefully planned tactics is the point, then you want to to simplify economy as much as possible to keep the game from exceeding a one-shot time limit.
The exception to this is if you can make the game appeal to the RPG model of tabletop gaming where you put people into story driven campaigns that are meant to draw out across 20+ hours of gaming. Doing this with competitive strategy games normally does not work well for a number of reasons, but if you could work it out such that your kingdom can exist in a similar format to an RPG character sheet that can be easily picked up and returned to later, then this might be doable. If this is the case, you can build very complex economies and tactics whereby players become interdependent on each other for trade and resources, but this may be a way better type of system for co-op gaming than competitive.
Then there is balance. Does a catapult really cost as much as a frigate? In real life the answer is no, but if the mechanics in the game make them equally useful, then they should cost the same regardless. In general, the best games give you a reason to own all of the units that exist in the game. If an army of knights can just wipe out whatever they encounter, then your other 10 unit types will just be dead weight in your game box, but if knights are so expensive that they have to be selectively deployed, then you will see people need to make mixed armies. So, economy is often a tool used to balance game elements that are inherently unbalanced.
] |
[Question]
[
Science fiction shows us two common shapes for large space stations, rings and tubes:
Deep Space 9 ([image source](http://startrek-ships.com/wallpapers/star-trek-deep-space-nine-station/)):
Similarly, [2001: A Space Odyssey](https://i.stack.imgur.com/LzB4a.jpg) ([image source](https://worldbuilding.stackexchange.com/q/4327/28)).
On the other hand, we have Babylon 5:
([Image source](http://www.midwinter.com/lurk/universe/station-1.html).)
The [International Space Station](http://www.nasa.gov/audience/forstudents/5-8/features/what-is-the-iss-58.html) isn't a city in space (it holds fewer than 10 people), but it's the only actual data we have. It follows the latter approach.
Which style makes more sense for a city-sized space station, one where people live permanently, work, and do commerce? Does it depend on what it's in orbit above (if anything)?
In your answer please consider factors that go into both building it and maintaining it. If one is more expensive to build but would be less expensive to maintain, then it's possible that it's still better in the end. (Expense isn't the only factor; usability factors matter too.)
Assume we've already identified a site for this station.
Assume we are limited to things we know how to build, and have the materials to build, today.
[Answer]
**Tube shaped will be your best bet**
Space stations are expensive to produce, so there is going to be a strong preference for choosing shapes which are efficient at accomplishing their goals.
One of the goals of a space station is gravity. Most Sci-Fi books choose to have a source of a gravity-like force because there is just too much evidence that humans don't do well without it. Barring fictitious gravity engines, centripetal acceleration is the easiest answer.
Centripetal acceleration has an interesting flaw. As discussed in *Rendevouz with Rama*, any rotation also causes centripetal acceleration's bothersome cousin, the Coriolis effect. Human brains seem to have trouble with this (though there is little research into how we would handle it if we grew up on a station). The solution is always to keep the angular rate slow, to minimize Coriolis. This means big radii to get the "gravity" you want.
**For the smallest of stations of this sort, rings are popular.** It is common to want to have lots of your space at one common G force, so much of your station should be at on radius from the center of rotation. This minimizes materials per volume at 1G. Often this is supported with "elevators" that go through the center of rotation to short circuit the long distance along the ring.
**As the station gets bigger, and transit becomes more of an issue, there is a desire to expand in a second direction.** The ring widens, becoming a revolved ellipse instead of a revolved circle, looking more like a wristwatch band. This transition from "maximize volume of space to 1G" to "balance volume of space at 1G with the distance between points in the city" separates the simple rings from these widened rings.
**At some point, the ring becomes so wide that another shape takes over: the cylindrical tube.** A ring has to maintain pressure-grade materials on all sides. At first this is efficient, but when the ring becomes wide enough, it starts to look like there's extra material to be shed. The station starts to look like {wall} pressure-space {wall} vacuum-in-the-center-axis {wall} pressure-space {wall}. In fact, it starts looking like a cylinder, but with no end caps and double-walls on the rest of it. If you skin the end caps, and pressurize the whole area, you can ditch half the walls. If the ring is wide, this can be a substantial boon.
**Arthur C. Clarke's Rama was of this shape and size. It was 54km long and 20km in diameter, which rotated with a period of 4 minutes per rotation. It is a reasonable size for a city spaceship.**
**Of these shapes, the one that is conspicuously missing is the sphere.** This is because of the desire to have a constant "gravity" over large areas. Spheres are great at material-to-volume, but they have a constantly varying radius as one changes "latitudes," which could be undesirable. However, if one is comfortable with differing gravities like that, the sphere is the most efficient shape you can have
[Answer]
**Toroidal.**
Bear with me here. This is going to take some explanation, but maybe I can explain myself.
Shokhet and Cort Ammon solved the problem of making sure that the station spins properly. A cylinder is probably the simplest solution to that problem, because it's easy to build and maintain. The problem, though, is that it soon becomes hard to get from one end to the other. As you mentioned, Cort Ammon,
>
> As the station gets bigger, and transit becomes more of an issue[.]
>
>
>
This is going to be a *huge* problem if you want to make a city. You could make a disk-shaped station (to save the rotational aspect and thus gravity, while making it easier to get from one spot to another), but this still requires the station to be large. It'll look like a giant pancake. Eventually, you're going to want to extrude it into a cylinder.
My solution (independent of Shokhet's suggestion, and implemented completely differently) is to create a toroidal space station. This essentially takes Skohet's and Cort Ammon's cylinders and bends them around so the ends meet. Voila! You can get around easily. The reason that toroidal space stations are so popular, as Shokhet said, is that you can rotate them along an axis going through the open center of the torus. My idea is a bit different.
The cross-section of a torus is a circle. You can form a torus pretty easily by graphing a circle on the Cartesian plane and rotating it about some line (you can calculate its properties using calculus). The point, though, is that you can break up a torus into a series of circles. This can be exploited to generate artificial gravity. Instead of rotating the entire space station along one axis, I would rotate lots of smaller circular segments along an axis going through the center of each segment. This would create artificial gravity along all sides of the torus. Rotating a torus about its center wouldn't create this effect, because the "top" and "bottom" would not be effected. The advantage of this design is that it creates artificial gravity along *all* parts of the surface - which is necessary to fit everyone into a city-sized space station!
The idea has its plusses and minuses, of course.
**Pros:**
* *Artificial gravity wherever you like.* I'm really pushing this point, but there's another upside: You could rotate each segment at different rate, providing different gravities (or no gravity at all). Think about how useful this would be for a space station containing many different alien races. Each one is accustomed to a planet with a different gravitational field. If you have a space station with one strength of artificial gravity, most would be unhappy. Here, this is fixed. *Note: You could break up a cylindrical station just as easily.*
* *You can get just about anywhere pretty easily.* Part of my motivation for this configuration was that you can't easily get from a point on one end of a cylindrical space station to another. This could of course be solved by planning - that is, designing the station such that people on one end won't *need* to go to the other. But it's probably best to make all areas equally accessible. On this station, all you have to do to get form one point to another is to simply travel through the center of each segment. You could also bridge the central gap by creating "bridges" from each segment to another.
* *It's compact.* Let's say you want to make a cylindrical space station that has a surface are of 10 cubic miles. You also want a radius of half a mile, to make it easy to make the artificial gravity you want. The formula for the surface area of a cylinder is $V=2 \pi r^2 + 2 \pi r h$; some algebra leaves us with $h=\frac{10 - 0.5 \pi}{2 \pi (0.5)}= 2.68$ miles. That's pretty long. A torus with the same area is a bit shorter. The formula for the [surface are of a torus](https://en.wikipedia.org/wiki/Torus#Geometry) is $4 \pi ^2 (Rr)$, where $R$ is the radius of a circle whose circumference equivalent of the height of a cylinder and $r$ is the radius of a circular cross section. This is explained better in [this](https://upload.wikimedia.org/wikipedia/commons/8/81/Torus_cycles.svg) graphic:
$R$ is the radius of the pink circle; $r$ is the radius of the red circle. We set $r$ to 5 and find
$$R=\frac{10}{4 \pi ^2 (0.5)}=1.59$$
The width of a torus is $R+r$, which becomes 2.09 miles, a slight improvement. Note, though, that a sphere would be the shape which is the easiest to travel through.
**Cons:**
* *Not easy to build.* It's tough to build a circle or a cylinder because of their curved side(s). This is even harder in the case of a torus, because it has many curved sides. It's highly irregular. Your best bet would be to build it in the segments which will be used to generate artificial gravity.
Frankly, I think the pros outweigh the cons here.
---
Let me end by addressing some of the specific things you mentioned in your question.
>
> Does it depend on what it's in orbit above (if anything)?
>
>
>
From a logistics standpoint, the answer is yes. You need to re-supply any station that is not self-sufficient. However, this is simply a problem for *all* of the proposed ideas, not just this one. And it can be avoided by making the station completely self-sufficient. I'm being vague here on purpose, because there are a lot of factors that would go into solving this problem.
>
> In your answer please consider factors that go into both building it and maintaining it. If one is more expensive to build but would be less expensive to maintain, then it's possible that it's still better in the end.
>
>
>
I don't think that there would be a huge change in expense among the different ideas. You need to have $X$ dollars/pesos/pounds/yen/euros to maintain a station of a given surface area. Unfortunately, all of these stations that have artificial gravity need to have the same surface area, so this isn't going to change.
---
Peteris recently said
>
> Umm, How do you propose to rotate sections of a torus? A torus cannot be made of cylindrical segments without gaps or overlap; in a torus, the "inside" part of each section is narrower than the outside, and can't rotate along the red circle in your drawing.
>
>
>
I completely forgot about explaining this part. My "toroidal" space station wouldn't be a perfect torus. As I said, it would be made of segments. However, I didn't explain that the segments would be closer to cylinders than slices of a torus. Think of small cylindrical pieces connected by wedges. Each piece rotates, creating artificial gravity. The torus isn't perfect; it's an approximation.
[Answer]
Why would you choose a ring (or torus) over a tube (or cylinder)? First, you would choose either over other shapes because they spin. If you're not spinning, there's no point in either shape. This is why the International Space Station (ISS) is neither tube nor ring. It's just a bunch of modules stuck together. It's a little closer to a tube shape, but it's actually shaped more like a series of buildings connected by tunnels. So the main reason to choose a ring or tube is because you can spin them.
The fictional Deep Space 9 (DS9) has the same problems as an example as the ISS. It looks a bit like a ring, but it actually isn't one. People live in the center of DS9, not on the edges. This is because DS9 doesn't have to spin to create gravity. It has artificial gravity that works in a way unknown to our physics. If we do build ring shaped space habitats, it is unlikely that they will look like DS9. They will have more on the edges and less in the middle.
The primary advantage of a ring is that it can be smaller than a tube for the same radius. You want to maximize the radius because gravity is generated by the illusion of **centrifugal** force, that is force away from the center of the spin. This is actually a fictitious force, as the real forces are inertial (in the direction of the spin) and centripetal (from the floor keeping you from following the inertial force). Increasing the radius reduces the side effects of the spin (e.g. the Coriolis effect). For a small radius, you are constantly changing direction. A larger radius makes the change of direction more gradual.
It's easier to make a ring that uses less atmosphere. You can make a tube with another tube inside it, but for a similar expenditure of material, you could make a larger radius ring. The rings are generally shown with a center that is either hollow or contains spokes. You could make a disc instead of a ring, but that would have a lot of unused atmosphere in the middle. We can guess that rings are cheaper in atmosphere while cylinders are cheaper in structural material.
There is some reason to believe that structural material is easier to obtain in space than atmosphere. In particular, we can mine the asteroid belt for structural material while we'd have to mine comets, moons, or planets for atmosphere. After Earth, Venus is the closest planet. Everything else is at Jupiter's orbit or farther. Comets can come closer but they are small and move comparatively quickly. So we'd spend a lot of energy to match speeds. Saturn's rings might be the best source, but they are far away and still partly in the gravity well.
The ring provides more structure. Note that the spin will affect objects that are attached to the "ground" or floor most, then objects that rest on the floor, and will affect things like atmosphere the least. The obvious result would be that the side of a building that faces into the spin would have a thicker atmosphere than the sides or the leeward portion. How much of a problem will that be? What kind of weather side effects would occur?
It would be easier to run an elevator from point to point on a ring, as there's already structure there (the spokes of the ring). It would be more difficult with a cylinder, as you'd have to create the structure for the elevator. Cylinders are more compact though, so it might be easier to run a shorter track along the edge of a cylinder than to run through the middle of a ring. You could also fly in a cylinder.
A ring would likely be forced to use artificial light. Rings have too much structure to work well with windows. A cylinder can be constructed such that windows let in light regularly. Unfortunately their rotation speed doesn't support a day/night cycle, so it's unclear if we'd do this. We might be able to give a night cycle by "shutting" the windows. This is either an advantage of cylinders or irrelevant. Perhaps both use artificial illumination.
The real truth is that we don't know whether we'd prefer a ring to a cylinder. Unfortunately, we've never had the resources to try either of them. Our current International Space Station doesn't have artificial gravity. We don't have any real understanding of when the simplicity of the wider ring of the cylinder outweighs the advantage of a decreasing side effects from a greater radius. We have no experience of how either would impact atmospheric effects.
Our best guess is that we'd start with rings, as they are easier to build for smaller capacity. As our needs increased, we'd switch to cylinders, as it is easier to move from point to point on them. So for something big enough to be a city, it is more likely that it would be cylindrical. But that remains speculation at this point, as we have no experience with either.
[Answer]
I would suggest that **tube-shaped** cities would be the better setup for a city, because it would be a lot **easier to travel and transport materials** around the the city if all you had to set up was a series of elevators that go up and down, instead of carts on a weird track that travel *around* your ring.
---
*A note on setting up floating cities:
Most science fiction I've read assumes that a [torus-shaped](http://en.wikipedia.org/wiki/Torus) (ring-shaped; not [Taurus-shaped](http://en.wikipedia.org/wiki/Taurus_(astrology))) is the best arrangement for cities in space, because spinning them around their center can provide a sense of gravity through [centripetal force](http://en.wikipedia.org/wiki/Centripetal_force) -- basically, as the structure spins, the inhabitants are pressed against the inner-side of the outer wall to imitate gravity. This is also possible with a tube-shaped structure.
But if you want gravity, **make sure it spins**.*
[Answer]
**TL;DR:** Neither. The easiest thing would be to populate an asteroid, small moon, pseudo planet or comet.
Longer explanation: Space stations (of the unknown distance future) will be *big*. And that means that we need resources. And wasting them isn't an option. We can't afford to loose them on our home planet. And the needed resources boil down to *where* the station gets built.
## Built in space
That means that we would have either travel long distances to get hold of the needed materials and bring them to our factory place or that we would have to bring them up from a planet. In both scenarios we loose a lot of time and waste a lot of resources just to transport semifinish and parts.
## Built on the surface
No matter on which surface we build it, we need to bring the whole thing into some orbit or into some place where it stays (relatively). Again we are wasting resource. Maybe even more as the structure would probably need to levitate and raise itself into position.
## Populating asteroids
Depending on the building materials, we can find a lot of the needed resources in place. We also have a finished outer shell. And depending on the mass we could easily rotate it. Also they come in various sizes and drilling rings and tubes into it, sealing the walls off with fluid concrete (or a similar material mixed with the gravel already in place) could be done quickly. Pretty much like we build tunnels through mountains nowadays. Oh, and it's easily [***exchangable***](https://www.youtube.com/watch?v=LX6ghwNZm7M) as nature showed us.
[Answer]
There is an interesting document for a small spacestation-city called Asten on the NASA homepage. While I don't understand enough to follow all the Details it sounds reasonable and goes not only in the Question of construction (Form/Materials/and so on) but also things like infrastructure and supplies for the Population.
Since I can't reliably condense the 93 pages, here is a link:
<http://www.nss.org/settlement/nasa/Contest/Results/2009/ASTEN.pdf>
For only the form of the spacestation they suggest a cylinder constructed out of individual rings.
[Answer]
I believe it comes down to **artificial gravity**.
**A torus** can be set to spin at the proper rate in which case it would have a centrifugal force pushing outwards and producing a false gravity to the outside of the ring. The 2001 space station does this.
In the case of **the cylinder**, if the city is in transit to another system it could accelerate at a constant 1G (~10m/s/s) and then there would be an artificial gravity towards the rear of the vessel. In this case floors could be stacked transversely to the direction of travel. This sort of vessel would accelerate towards its destination and then at the half way point perform a maneuver to turn around and then decelerate at the same constant rate until it reaches its destination. Such a vessel could spend several generations in space.
IMO, those are the two most realistic scenarios.
Alternatively, a vessel in transit could also be set to spin and could have floors within it designed to have a camber that matches the balanced forces somewhere between the the centrifugal forces and accelerating forces.
Note that the DS9 station pictured above does neither of these relying instead on some other fictitious gravity generation devices. AFAIK, there is no known way to generate such gravity.
] |
[Question]
[
In series such as the *Hyperion Cantos* and *Ender's Game*, there exist fictional faster-than-light communication systems allowing either instantaneous, or near-instantaneous transmission of information.
Are there any (or what are some scientifically plausible) methods of faster-than-light communication, and what are some important things to consider when applying one of these methods?
[Answer]
Our society does not yet have sufficiently advanced science to be able to answer this question.
However, in most science fiction, there are three commonly used approaches. Note that I am NOT claiming any of these would actually work.
1. Wormholes, or something like wormholes that directly connect two points in space
2. Subspace, or some other kind of one-for-one mapped parallel space through which signals can be transmitted at speeds that are effectively faster than the speed of light in normal space.
3. Quantum entagled particles, where two particles have a quantum level connection such that when one particle is manipulated, it affects the other particle. Communication is instantaneous, but things such as FTL travel can break the entanglement (meaning that devices must be shipped on slower than light transports). For an example of this use: [Singularity Sky by Charles Stross](https://en.wikipedia.org/wiki/Singularity_Sky).
One thing we know *won't* work is gravity waves. In the Honor Harrington universe, gravity waves are faster than light, but recent advances have proven that gravity waves only travel at light speed.
[Answer]
Those who trot out *tachyons* need to [keep reading](http://math.ucr.edu/home/baez/physics/ParticleAndNuclear/tachyons.html):
>
> The bottom line is that you can't use tachyons to send information faster than the speed of light from one place to another. Doing so would require creating a message encoded some way in a localized tachyon field, and sending it off at superluminal speed toward the intended receiver. But as we have seen you can't have it both ways: localized tachyon disturbances are subluminal and superluminal disturbances are nonlocal.
>
>
>
This result is part of the original papers that coined the term, but everybody stops reading with "faster than light" and assumes that you could use them in the familiar matter with the familiar rules.
There is also a good description by Leonard Suskind in a Stanford lecture on youtube. He shows they are like inverted pendulums tied together with springs, and a disturbance still propagates in the sub-luminal manner.
See also [this Answer](https://worldbuilding.stackexchange.com/questions/20628/life-at-faster-than-light/20644#20644) where I went into that already.
---
Now for ansibles etc. What is "instantaneous"? There is no universal agreement on synchronization, and for space-like separation (as in FTL communication) there is no agreeement on the ordering of events.
So you can't *just* say it's instantaneous because there is no such thing. Instantaneous in *one* reference frame, not so much in others, and time travel reverse-causality in the rest. The same events will be all of the above to different observers.
An easy solution is to have your anibles work in a single ansible reference frame, as discussed [in this answer](https://worldbuilding.stackexchange.com/questions/46873/are-there-any-ways-to-allow-some-form-of-ftl-travel-without-allowing-time-travel/47038#47038). (Note that comminication is just travel for messages.)
---
Plausible?
When Carl Sagen had that question, he asked the physics community and Kip Thorne came up with wormholes.
The *Giants* novels used microscopic wormholes that could pass photons with short wavelengths. The time-travel bit was pretty much ignored until the series decided to exploit it wholesale.
[Answer]
The closest thing to FTL communication is communication via a wormhole. This wormhole need not be large enough for anything but a photon to be able to pass through, but if the mouths of the wormhole were separated, the photon would enter one mouth and exit the other in less time than it would take to travel the real-space distance between the mouths.
It would be necessary to generate a wormhole, and then to carry one mouth of the wormhole to the intended destination of the communication. This could take some time.
This answer presupposes that it is scientifically plausible to generate and maintain a wormhole.
[Answer]
Donald.McLean's answer is very good. Just as an addition, there are theories about the existence of [tachyons](https://en.wikipedia.org/wiki/Tachyon), but most Physicists think they cannot exist. Tachyons are (in these theories) particles that move only faster than light, and can not reach the speed of light, the same way normal massive particles can't.
It is known that you can transform energy into matter and vice-versa (so it is possible to transform light into matter and vice-versa).
Hypotethically, there could be a similar device for tachyons, making a conversion between particles and energy. There is (at least) a pair of short tales about that (these two are in spanish) out there, first one about how the technology which discover them and the second one about possible usage:
[Tanawa meters](http://fantaciones.blogspot.com.es/2008/09/los-medidores-tanawa.html)
[Tachyons](http://fantaciones.blogspot.com.es/2008/09/blog-post.html)
In short, you can use a laser (pure light) to create tachyons and modulate them. These would travel faster than light itslef and can be readed at the other end by a similar means.
[Answer]
An answer to this question that hasn't come up yet relies on a certain interpretation of quantum mechanics, namely, Bohmian mechanics or pilot-wave theory. In a pilot-wave theory (PWT), you have a wavefunction like in ordinary QM, but you also have point particles with definite locations (or fields with definite values, depending on how the idea is extended to QFT).
Typically in a PWT, when you have an ensemble of systems with identical wavefunction, the actual positions of the particles are distributed according to Born's rule, a condition which is called quantum equilibrium. But PWT also allows for the possibility that we could have an ensemble of systems which are not in quantum equilibrium. In such cases, a number of things become possible:
* faster than light communication via quantum entanglement (the no communication theorem doesn't apply in these cases)
* violation of quantum uncertainty principles
* measuring the quantum state of a system without disturbing it
* incredibly powerful quantum computation
(The last two items basically break all modern cryptography schemes, by the way.)
For FTL communication, this would interact with relativity by effectively defining a reference frame (or more generally, a foliation of spacetime) in which the communication was instantaneous. It would not allow any time-travel loops or paradoxes.
Another interesting feature of this kind of FTL communication is that, since it doesn't propagate via a signal, it can't be blocked, intercepted, or interfered with in any way (though if the initial entanglement is established by transmitting entangled photons for example, those might be intercepted).
The details can be found in this paper by Antony Valentini: <https://arxiv.org/abs/quant-ph/0203049>
[Answer]
YES (but really no)
Empty space isn't really empty -- there are quantum-mechanical "vacuum fluctuations" that the light interacts with, theoretically slowing it down. The Scharnhorst effect ( <https://en.wikipedia.org/wiki/Scharnhorst_effect> )says that light itself should travel faster if going through a special vacuum -- one with fewer vacuum fluctuations.
That hasn't been demonstrated or proven mathematically, but seems plausible enough.
However the only way we know of to reduce vacuum fluctuations is to have two plates very, *very* close together. And the effect would be tiny ("A photon travelling between two plates that are 1 micrometer apart would increase the photon's speed by only about one part in 10^36"), so small it's beyond today's technology to verify or refute the claim.
So... We *might* be able to send a signal very, *very* slightly faster than c, if we're sending the signal about an atom's diameter in distance.
Western Union is reportedly unconcerned.
[Answer]
Nothing can travel faster than light speed, however you could simply use wormholes to send signals between two points at "faster than light speed".
[Answer]
JDługosz and Donald have given the best answers so far. I'll just add a small, extra suggestion: [Alcubierre Drive](https://en.wikipedia.org/wiki/Alcubierre_drive) mail.
The Alcubierre Drive is an hypothetical means to "contract" space around a body, so that a ship could artificially shorten the distance between any two points it would travel through. For all effects, such travel would appear to be FTL for outside observers.
So you could write a letter, post it into the nearest alcubierre mail post and wait. It would get there faster than a beam of light would.
However, the equations involved seem to indicate that anything around the ship will be destroyed as it moves:
>
> Brendan McMonigal, Geraint F. Lewis, and Philip O'Byrne have argued that when an Alcubierre-driven ship decelerates from superluminal speed, the particles that its bubble has gathered in transit would be released in energetic outbursts akin to a sonic boom shockwave; in the case of forward-facing particles, energetic enough to destroy anything at the destination directly in front of the ship.
>
>
>
So you should be really careful about whom you are sending your messages to, unless you're mailing people you really don't like.
[Answer]
YES there is.
It's just a hypothetical particle, but the [tachyon](http://en.wikipedia.org/wiki/Tachyon), if existing, is faster than light.
We can't tell if it exist, but at least it's plausible and this handy for any not fantasy based sci-fi scenario.
Einstein was talking about a [Time-Telephone](http://en.wikipedia.org/wiki/Tachyonic_antitelephone) which would allow to send information back in the past, but not the future. This hypothetical device is based on tachyons.
[Answer]
Note that FTL communication breaks the theory of relativity since FTL is equivalent to time travel (under some frames). Thus the best scientific knowledge is that tachyons, quantum entanglement and so on cannot carry *information* faster than the speed of light.
Since scientific theories such as the Theory of Relativity are not mathematically proven it is "plausible" that they will be disproven. However, given the many answers that assume that relativity is wrong, it is interesting to note that the existence of [pseudo-telepathy](https://en.wikipedia.org/wiki/Quantum_pseudo-telepathy) is a known scientific fact and not limited to the speed of light.
The standard example is two space captains (Alice and Bob) who want to meet only if they both agree. They have the option of travelling to star system A or B. They say they want to meet, and they both receive a message saying to travel to system A. They arrive at system A, and meet.
Now they have received something *information-like*, because they were able to agree to meet, not limited by the speed of light. However, this doesn't break causality. They each have a 50% chance of receiving "A" regardless of what the the other captain responds, so there receiving "A" by itself gives no information about the other space captain. No information is exchanged until the captains meet, which happens slower than the speed of light.
Quantum mechanics doesn't allow the captain problem to be solved with 100% accuracy, but still much better than random chance.
Depending on the feel of your universe pseudo-telepathy might work better than actual communication. Imagine oracles spread across the galaxy with some from of pseudo-telepathy device wired into their brain. It gives a 100% scientific reason to have oracles that give cryptic statements that tell you what you need to know (but you don't know why until after), if that's your thing. There are limits to the what can be achieved by pseudo-telepathy, but the oracles may not even really know when they are just guessing. The main characters don't necessarily know the exact details, they consult the oracle and it works out (or not) as required by the plot.
[Answer]
**Quantum entanglement**
in theory no useful information is transmitted but if you could find a way to measure whether a particle is superimposed or not (something that technically does not violate the Heisenberg uncertainty principle) you could send individual bits faster than light (technically at infinite speed).
] |
[Question]
[
In this [photography stack exchange question](https://photo.stackexchange.com/questions/89875/why-do-we-use-rgb-instead-of-wavelengths-to-represent-colours) about why we encode pictures in RGB, several answers talk about the fact that our visual receptors are trichromatic, which is the inspiration for the RGB system. Not only is it the inspiration, it appears that we use RGB to encode colors explicitly *because* we have trichromatic vision.
It's my understanding that digital screens are composed of pixels, where each pixel is composed of three colors: red, green and blue. To form a color, each pixel is turned on precisely to the proportion specified by the RGB value. Since this happens at such a small scale (from far away), the colors mix and we get end up with a brand new color.
My question is this: If we use this scheme to trick our brain into thinking we're seeing a different color as opposed to using specific wavelengths and amplitudes, would an alien with a different visual perception system be able to see the colors in our digital screens? If another being had a tetrachromatic visual perception system or a true-wavelength perception system, would they perceive the same colors from our trichromatic screens?
In other words, is our mixing of the three colors *actually* producing this new color, or are we just tricking ourselves to think that it is?
[Answer]
>
> If another being had a quadchromatic visual perception system or a true-wavelength perception system, would they perceive the same colors from our trichromatic screens?
>
>
>
Of course not. [Tetrachromacy](https://en.wikipedia.org/wiki/Tetrachromacy) is real, can occur in humans, and she indeed seen differently:
>
> In 2010, after 20 years of study of women with four types of cones (non-functional tetrachromats), neuroscientist Dr. Gabriele Jordan identified a woman (subject cDa29) who could detect a greater variety of colors than trichromats could, corresponding with a functional tetrachromat (or true tetrachromat).
>
>
>
(From [Wikipedia](https://en.wikipedia.org/wiki/Tetrachromacy#Humans))
To answer your main question:
>
> Would aliens with different visual perception be able to read our screens?
>
>
>
Most probably **yes**. As you can notice, most of the information in our screens is coded by brightness-darkness, not actual colours. So if they can register wavelengths in our visible spectrum, they will be able to read our letters and navigate our websites.
Cells are responsive in quite wide bands, for example in birds:
[](https://en.wikipedia.org/wiki/Tetrachromacy#/media/File:BirdVisualPigmentSensitivity.svg)
If aliens are somehow similar, then no matter where exactly the peak will be, they will be able to register light or no light. Of course, the further away from our peaks, the more different would computer image look from the real world one - because computer screen only emulates the parts of the real-world look we, humans, notice, and not the full spectrum. Look for emission spectrums and absorbtion spectrums of various light sources and items to see them. Item with flat absorbtion spectrum will look gray / white to both us and them. Item that reflects similar amounts of our "peak" frequencies but different amounts where our cells are not so sensitive will look white-ish for us, but not for them. And so on.
[Answer]
# Sensations and physical quantities
Color is a *sensation*: it exists in the mind; it is not a physical quantity, that is, it does not exist in nature. Since color is a sensation, all measurements of color are made with reference to a hypothetical "[standard observer](https://en.wikipedia.org/wiki/CIE_1931_color_space#Tristimulus_values)"; the color discrimination ability of most men with normal color vision is somewhat poorer than standard observer's, that of most women is somewhat better. Importantly, what is measured by a color measurement does not necessarily match what is perceived by the brain -- the measurement is related to the sensation of color only for extended objects, that is, objects which subtend a large part of the visual field; for smaller objects other mental mechanisms come into play which make a mess of the "objective" measurement. For illuminating examples, see professor Akiyoshi Kitaoka's [illusion pages](http://www.ritsumei.ac.jp/~akitaoka/index-e.html), for example, [page 13](http://www.psy.ritsumei.ac.jp/~akitaoka/color13e.html).
For extended objects (objects which occupy a large part of the visual field), the *sensation* of color is related to the *physical quantity* [spectral density](https://en.wikipedia.org/wiki/Spectral_density) of light; the relationship between the spectral density of the light and the perceived color is complicated but predictable using empirically measured formulas. For smaller objects the perceived color *cannot be determined* from the power spectrum of the light coming from those objects; only by taking into account the entire scene can the color be predicted (approximately), and there are no good formulas.
# RGB is not enough and cannot be
The [International Commission on Illumination](https://en.wikipedia.org/wiki/International_Commission_on_Illumination) (CIE, *Commission internationale de l'éclairage*) carried out an extensive set of experiments which determined that the standard observer can match any given color by varying three parameters. (Essentially, the test subjects had to match the color of a light source with the color of another light source which could be modified by turning three knobs.) Mathematical calculations showed that combining three abstract light sources is enough to match any visible color; unfortunately, the three abstract base colors which define the [CIE 1931 XYZ](https://en.wikipedia.org/wiki/CIE_1931_color_space) color space are *non-physical*, that is, they cannot exist. (They are a red much redder than the reddest visible red, a blue very much bluer than the bluest visible blue and a green a little greener than the greenest visible green.)
In practice, we either accept than any three visible fundamental colors will be able to reproduce only a part of the visible colors, or, if we truly want to reproduce a larger part of the visible color, we accept that we need more than three fundamental colors. For example, high-quality color reproduction on paper is done in hexachromatic processes; for color reproduction on screen advanced televisions use four base colors.
In particular, the commonly used [sRGB](https://en.wikipedia.org/wiki/SRGB) color space can reproduce less than half of the visible colors, which is understandable given that its [primary colors](https://en.wikipedia.org/wiki/Primary_color) are chosen so that they match the colors of the [phosphors](https://en.wikipedia.org/wiki/Phosphor) available for color TV screens in the 1950s. In particular, the green primary of sRGB is very poor; sRGB simply cannot reproduce luminous saturated greens.
*[CIE 1931 xy chromaticity diagram showing the gamut of the sRGB color space and location of the primaries](https://en.wikipedia.org/wiki/SRGB#/media/File:Cie_Chart_with_sRGB_gamut_by_spigget.png). By Spigget, made available of Wikipedia under CC BY-SA 3.0.*
(There exist computer monitors and television sets which can reproduce a wider gamut than sRGB; but the problem is that (1) they are very expensive and (2) the overwhelming majority of visual media are encoded in sRGB. Look for "wide gamut" monitors, which are not the same as "deep color" monitors. Even monitors which can faithfully reproduce more than 95% of the sRGB gamut are quite expensive.)
# So how come we *can* use sRGB?
Remember that color is not a physical quantity, but a sensation which exists in the mind. The perception of color is seldom absolute; in most practical situations it is the color contrast which counts. As a consequence, cameras and image manipulation software which use the sRGB color space *cheat* by mapping the visible colors to the smaller representable gamut. As a commonly encountered representation in the user interface, you may seen some color printer drivers offer a choice of *intents* when reproducing colors; common choices include pictures (mapping all colors to the device gamut) and presentations (clipping colors to the device gamut).
# How would an alien perceive our screens?
All the preceding discussion intended to convey that the perception of color is different for different humans, no aliens needed. But to come back to the question: we are obviously unable to picture the sensations of an alien which has a color vision system with more primary stimuli than ours; but we can make an attempt at an analogy.
All user interface designers are taught that colorblindness is a thing, and that about 10% of human males have less-than-standard color vision; for this reason, user interfaces should always be checked for usability by colorblind people, and there are countless software programs which attempt to simulate what a colorblind person sees.
[](https://i.stack.imgur.com/z06FR.png)
*A beach scene in natural colors and simulated red-green color blindness. Own work by AlexP, simulated color blindness made using the [Color blindness simulator](http://www.etre.com/tools/colourblindsimulator/) from [Etre](http://www.etre.com/).*
We can intuitively imagine that for the multi-chromat alien our screens will have a similar relationship to a full-alien-color image as the simulated colorblindness images have to our full-human-color pictures. This is a gross simplification, obviously. One immediate example of why this is an oversimplification: imagine that the alien sees yellow as a primary color, whereas humans cannot -- we cannot distinguish between a mixture of red and green and monochromatic yellow; to the alien, all yellows in the picture will appear as weird color shifts.
# But would they be able to read the screen?
Well, that really depends on what part of the electromagnetic spectrum they perceive as visible light. If their visible light overlaps with ours then yes, they will be able to read black text on white (or white text on black), although for them the white may not be white but some color. They may even be able to read some color combinations which are hostile to a human reader, such as the infamous magenta text on green background...
[Answer]
Looking at Earth and the animals that we share this planet with, it has already been shown that other animals with different color perspective, like octopuses, dogs, cats and others can observe television screens and react to what happens on them:
* Dogs have been seen chasing after virtual balls a baseball pitcher throws at the screen.
* Cats have been seen trying to catch mice or birds that appear on a monitor.
* Octopuses have been seen in lab environments to be able to interpret images shown on a monitor and respond to them.
* During WW2, a series of tests was run using pigeons in bombs tapping on monitors to guide the bombs to their destination.
Now, these aren't aliens, but they do have different visual perception to humans. The main requirement is that the species evolved in an environment where the most prevalent light is in the human-visible light spectrum. An alien that grew up perceiving mainly infrared or ultraviolet light would be less likely to see our monitors, simply because those monitors are designed to have uniform output in the other spectrums.
[Answer]
The previous answers explain the physics well that's behind color vision. Based on these physical principles, I would like to elaborate on the interesting cases where the aliens *cannot* read screen content that humans could, as the question title suggests.
## Trivial case: Their eyes are no responsive to our wavelength spectrum
As mentioned in previous posts, they are obviously not able to read our screens if their eyes are not responsive to our screens' spectrum. We can for example envision a life form that lives in the energy-rich surroundings of a black hole. They would probably have optical receptors that are suited for that wavelength range, and not so much for our optical wavelengths.
The more interesting case arises when their color vision (let's assume they also have multichromatic vision) *is* sensitive in our optical region.
[](https://i.stack.imgur.com/nymopm.jpg) Black hole optical spectrum. Image from: <http://astrophysics.fi/index.php?p=bhc_descr>. The optical spectrum that's visible for humans is around 2 \* 10^-3 eV in that graph
## Flatbands: Equal luminosity is invisible!
So let's stick to our example of aliens living close to black holes. To have eyes that are sensitive to our visible light spectrum, they need extremely broadband eyes. It's thus quite probable that our visible light spectrum is so thin that it looks like just one single color.
The same holds if our visible spectrum is at the very border of their visible spectrum - only one receptor would be receptive, and they would see everything in the same color, much as we perceive all red colors above 630nm as the same red.
Now coming back to computer screens, this would mean that they cannot distinguish between colors that have equal luminosity but different chroma (for us). So if we wanted to hide our computer screen content from their eyes, we'd have to display everything with different colors with equal luminosity. That would make it tiresome for humans to read, but it could work!
## High dynamic range eyes: Shadings are invisible!
We can make a similar argument for eyes with a very high sensitivity range for the visible receptors. If they live very close to a star, their eyes may be equipped for much higher light intensities than our eyes. They may also have a vision for lower intensities, however that vision might not be as well equipped as our vision to distinguish between small intensity differences. Gray text on white background may look just dark gray for them.
[Answer]
To add to previous answers…
In principle, if they share the same range of visual frequencies, they will be able to see the screen.
To *some extent* the colors will work even if they have different primaries. That is, chromatic colors (those on the edge of the horseshoe diagram or in a rainbow) will be simulated by *any* choice of pure frequencies on either side of it. If they have a small number of primaries too, they'll get the right idea. If they have many distinct primaries with narrow band filters, it will not work and they’ll perceive different un-natural colors instead.
For the purples, all bets are off.
Which different frequencies offer distinct perceptions may be very different from us. Consider a map coded with colors in the range of frequences that appear red-orange-yellow. The cold and hot marks on the map are *utterly* distinct, as red and yellow are different colors to us. Now the same range of values transposed up a bit would have the same frequency difference between high and low but it all looks blue to us, and we have poor discrimination of blues.
Someone might choose two widely different frquencies and suppose that they *must* be different colors, for anyone. But our vision forms a color *wheel* with purple looping back from violot to red. A species with more primaries might have a couple different distinct *loops* of color perception, or worse, they don’t normally loop for broad-band pigments in real life but are fooled by monochromatic primaries used in our displays.
So, there's lots of room for it to mostly work but have unexpected and surprising problems in specific instances.
] |
[Question]
[
I'm an artist and I've been trying to find a comprehensive resource that would help me clearly identify likely sky colors for exoplanets that have atmospheres with a similar chemical composition to Earth. It's trickier than I expected. I've cobbled together several resources, and built what I hope is a decently accurate chart of apparent sun color along with sky color.
**How accurate is my chart? Is this a good representation of sky/sun on alien worlds with heavily Nitrogen/Oxygen atmospheres? In what ways could I improve it?**
[](https://i.stack.imgur.com/A0Qwh.png)
**UPDATE: I've updated the chart. It's based on my latest research and indicates baseline sky color, cloud color, and apparent sun color for noon/pre-sunset.**
Latest science references: [Reference A](http://www.xenology.info/Xeno/5.4.2.htm), [Reference B](http://homepages.wmich.edu/~korista/colors_of_the_sky-Bohren_Fraser.pdf)
The chart is not meant to account for things like dust, the look of the sky at sunrise/sunset, or other atmospheric effects. This is meant to be a boilerplate for the baseline look of the sky during the day.
Here are the key ideas I've gleamed from my reading. If I'm wrong on any of these points I'd love to know! :)
* Earth-like atmospheres would tend to be light to dark blue at the zenith, due to the scattering of low-wavelength blue light. If the planet's sun was very hot, the sky would look a deeper blue, while cooler stars would give the sky a lighter blue to almost white look. When the sun gets to 3000k and below, the sky starts to take on an orange/brown tinge.
* Like on earth, the horizon is the lightest in color and the zenith the deepest.
* Denser atmospheres would appear brighter (more washed out) and the primary color in the spectrum more "pure" (I'm unsure what the term "pure" means exactly when it comes to optical perception). Likewise, thinner atmospheres would be less bright than earth's and the colors more "pure."
* With increasing pressure the sky color at the zenith becomes increasingly yellow. In my image this means that an earth-like sky at 10x earth pressure would appear blueish/green near the zenith.
* I'm assuming the sun would appear tinged by the color listed under "star temperature."
* I don't know how shadows would be effected, though I assume when you get down into K and M class suns, the surroundings on the planet would take on a progressively redder tinge due to the decreasing prevalence of blue wavelength light?
* I suspect the gradient of color from horizon to zenith will be steeper/gentler in some atmospheres?
I'd like to account for how the color would shift when you look in the immediate direction of the sun. Would the atmosphere surrounding the sun (like a "halo") appear tinged with the star's color?
[Reference #1](http://www.orionsarm.com/page/321), [Reference #2](http://homepages.wmich.edu/~korista/colors_of_the_sky-Bohren_Fraser.pdf)
---
Original Image:
[Answer]
**I think this is actually a good piece of basic artistic research** (I've had professors who have attempted it too).
Sadly, I can't give you an all-encompassing answer to your question. Even though you tried to refine your scope, I'm afraid in order to get what you are looking for you have to account for things that you didn't want to get into. I know I'm going to take a hit for this, but I needed the space to help you, so I will try to address some of the problems you have posed.
>
> (I'm unsure what the term "pure" means
>
>
>
In light, white light is actually an ~impure form of light in the same way that black/brown is an impure form of paint colors. Just like when you mix a bunch of paints together to get a brown-black color, so too if you mix a bunch of light colors you get a white-ish color. So "pure" in this context means closeness to an identifiable color in the spectrum.
>
> Is this a good representation of sky/sun on alien worlds with heavily
> Nitrogen/Oxygen atmospheres?
>
>
>
It's a start; however:
* Distance from star is just as important as its solar output, if not more so.
* Chemical composition (/stage of life) of a star can also have a small impact.
* Maybe the colors are accurate at the zenith; however, once you get to horizons you enter a whole hell of factors:
An atmosphere isn't some homogeneous blend of gases; actually, it has many layers with different types and concentrations of gases, especially when you factor in organic and volcanic processes. This plays out most notably with horizons, as the sun's light has to travel farther through those more erratic layers, the ones closest to the ground.
(See also: [link for why the moon appears orange](http://home.hiwaay.net/~krcool/Astro/moon/moonorange/))
So for your boilerplate approach, the spectrum emitted by your atmosphere should shift red as you approach the horizon from the zenith. The magnitude of this shift depends on the size of the planet/atmosphere, atmospheric density, etc.
>
> How accurate is my chart?
>
>
>
I can't say for sure, but I would expect to see more reddish tones in the lower-energy atmospheres.
>
> I'd like to account for how the color would shift when you look in the
> immediate direction of the sun.
>
>
>
Looking at the sun, the colors would be closer to the apparent light of the sun (its whitish output) and the zenith color of the sky (impure, as you would be seeing many different wavelengths of light being emitted).
>
> Would the atmosphere surrounding the sun (like a "halo") appear tinged
> with the star's color?
>
>
>
[Halos](https://en.wikipedia.org/wiki/Halo_(optical_phenomenon)) appear due to the presence of water, much the same way as rainbows appear. A halo would appear tinged with the star's color, but not to any significant degree for a human observer.
Just some useful [reading](https://en.wikipedia.org/wiki/Atmospheric_optics) if you haven't already.
>
> I don't know how shadows would be effected, though I assume when you
> get down into K and M class suns, the surroundings on the planet would
> take on a progressively redder tinge due to the decreasing prevalence
> of blue wavelength light?
>
>
>
A shadow is a shadow, being the absence of light. The color here depends a lot on what light the object receives and emits back.
[Answer]
You could improve it by means of adding all variations of elements and compounds in the atmosphere to add the atmospheric color association to those elements/compounds. For example, a sky with sulfur would look like..., ozone with hight traces of carbon would look like...
] |
[Question]
[
The species I have created looks eerily humanlike, practically indistinguishable from human except for a reptile-like tail and an exposed brain.
The top portion of the skull is replaced with a glass-like dome, which exposes the brain. The species I created lives on a planet filled with diseases and bacteria that primarily affect the brain, sometimes the physical structure of it but, other times, just the behavior. The glass dome is connected to the skin by a small metal-like ring that glows slightly in the dark.
My question is, **is what purpose or advantage would my species have by exposing the brain in a glass dome?**
[](https://i.stack.imgur.com/gIyHK.jpg)
For reference, this is what I mean by “glass dome”, which in the image, the brain is exposed from under the glass dome.
**Edit**, the glass dome on my species heads aren’t natural, and are surgically added to the head
[Answer]
There doesn't need to be any advantage. Your species simply thinks it is aesthetically pleasing.
Look at human history. We do all sorts of strange things in the pursuit of beauty. Depending on the culture we may mutilate our genitalia, ears, feet, neck, and even forehead in order to be more appealing for a wide range of reasons. Most commonly to attract the opposite sex though it doesn't always need to be for this reason. Sometimes we do it out of sheer tradition even long after the point where nobody remembers why we started doing it to begin with.
So to answer your question? It is a cultural practice. Perhaps your species highly values their minds and have taken to showing off the brain in the most direct and literal way possible.So long as they are advanced enough to perform the procedure without a high risk to the individual undergoing the process there wouldn't be a real barrier to it becoming a widely done cosmetic surgery. If it is connected to some form of religious concept it could even be ubiquitous for any individual who reaches a certain age to have it done.
[Answer]
It is precisely those diseases and bacteria that make the brain need to be visible and, potentially, accessible.
The bacteria and diseases attack the brain from the outside in, and they leave discoloration in their wake. Since they attack the outside protective layers first, this means that if one's brain is visible, the issues can be seen before any symptoms arise. As some of these diseases and bacterias can be extremely problematic but are easy to address if caught early, this has led to making the brain visible.
Further, some of the biologicals are used to the insides of bodies, and are succeptible to ultraviolet light. Having the glass dome allows for the largest produce of ultraviolet light - The sun - to kill these pests. The glow from the ring is also an ultraviolet emitter, and the wavelengths that kill the bacteria are just barely in the visible spectrum, leading to the glow in darkness. It also glows in daylight but it is much, much harder to see.
Going a step further, the early symptoms of some of the diseases might be easy to treat, but they permanently degrade the bone structure of the skull. The skilled and knowledgeable surgeons reinforce much of the skull and replace portions with the glass. This disease has been widespread, so huge numbers of your population have had these surgeries. Children, and those still growing, might not undergo this dome surgery immediately as it would have to be re-sized numerous times, but once they reach an age at which their body stops changing, they must get it since the bone is permanently weakened. They likely have had several surgeries to reinforce the skull in critical areas and prepare for the dome in the future.
[Answer]
A species, whose immune system can’t reliably protect itself against bacteria and viruses on its own planet, wouldn’t survive long enough to develop glassware, let alone brain surgery, let alone biocompatible materials for the skull-port.
An invasive mimic attacked their planet and threatened to wipe them out complete as a species. Every test the reptile-tailed humanoids came up with to identify the mimic failed. The mimc could exactly copy their blood, skin, respiratory and digestive systems. But, the mimic couldn’t duplicate their brain. The mimic’s brain looks diffent — like cottage cheese had sex with a Rumba different.
Too ensure their species survival, they all had these viewports installed in their skulls to show the are true . All non-viewport folk were hunted down and killed and eaten. To this day, once a grows out to adulthood they have the sunroof installed.
[Answer]
Their brain can produce additional energy from sunlight. It might even be the real-world photosynthesis mechanism applied to the brain (a green brain with chlorophylls).
I've found this amazing visual representation (that can be interpreted as a photosynthesizing brain):
[](https://i.stack.imgur.com/r3HsGm.jpg)
Source: <https://www.sott.net/image/s14/287378/full/download.jpg>
The alien species need additional energy for the high neural activity. They are smarter than humans. Additionally, they might need the additional energy to fight with the diseases.
Here is a relevant excerpt from a scientific article:
>
> This regulation is especially critical to the central nervous system (CNS) where energy consumption is highly dynamic. Within the brain, increased neuronal activity drives increased energy consumption and compensatory metabolic and vasculature changes in turn enhance neuronal function (Roy and Sherrington, 1890).
>
>
> While making up only a small fraction of our total body mass, the brain represents the largest source of energy consumption—accounting for over 20% of total oxygen metabolism. Of this, it is estimated that neurons consume 75%–80% of energy produced in the brain (Hyder et al., 2013).
>
>
> <https://www.frontiersin.org/articles/10.3389/fnmol.2018.00216/full>
>
> *Brain Energy and Oxygen Metabolism: Emerging Role in Normal Function and Disease*
>
> *Watts Michelle E., Pocock Roger, Claudianos Charles*
>
>
>
Addition:
You've provided an update that says "The dome isn’t natural, and is surgically added". I can provide some reasons that can justify my solution as well. They are born with a biologically transparent skull with a protective layer for brain to utilize the sunlight. The layer might not be strong enough and might be vulnerable to some of the diseases (or it can become more vulnerable in time). Thus, they surgically reinforce the skull with a strong transparent material. (It can be some sort of super glass). The material could block ultraviolet light which can be harmful to the brain. (In the real-world, in photosynthesis, plants use the visible light. They don't use the UV light). Also, the biological transparent layer might cover a small area so they make the transparent layer bigger to utilize sunlight more efficiently.
You can even think of similar but different scenarios. They weren't born with a transparent skull. They enhance the brain to utilize sunlight (they biologically/genetically alter the brain to perform photosynthesis or a similar process that would utilize sunlight).
---
Bonus:
* *Barreleye* fish was the first real-world example that came to my mind but their transparent skull is for increasing the field of vision of their tubular eyes.
[](https://i.stack.imgur.com/c2iGj.jpg)
<https://www.mbari.org/barreleye-fish-with-tubular-eyes-and-transparent-head/>
* *Gallamites* are a species mentioned in Star Trek with transparent skulls through which their brain is visible.
<https://memory-alpha.fandom.com/wiki/Gallamite>
* You don't need direct sunlight for photosynthesis, it occurs on cloudy days as well.
A more detailed answer: <https://biology.stackexchange.com/questions/9097/does-photosynthesis-occur-on-cloudy-days-or-does-it-require-direct-sunlight>
[Answer]
# Natural skulls just aren't big enough
This species developed a means of enhancing their intelligence by increasing the size of their brains, but a natural skull just did not have enough room to support their larger brains. Now, there's no saying the expanded skull cage *has* to be made of glass, but if you're going to expand your skull, you might as well do it in style. Glass has additional advantages in that it is not prone to bacterial growth like plastic, and does not rust or tarnish like metal. It's waterproof, airtight, and unaffected by most corrosive chemicals, and lasts for centuries if protected from chipping and/or shattering. (Though such damage could be repaired if necessary. Think about how people repair/replace car windshields when they get cracked.)
Now the one problem with glass is that unlike bone, it does not expand as you age. It's possible that a child might go through several upgrades to their glass brain-case as they mature. They may receive additional brain enhancement treatments at certain times that coincide with this. Possibly some of these pre-adult brain-cases might not be glass because they're considered to be temporary. But once a child reaches their full adult growth, they get their full-sized glass skull-cap. It's considered a rite of passage.
There may even be scholars who continue to increase their brain (and skull) sizes later in life. They may have even larger heads and be respected as wise elders among the community. The wisest of them all may have a brain case so large he/she cannot even support its weight and must sit on a throne with special support structure around it. This individual would be considered the wisest among all members of the species, and would be consulted as an oracle. They may even have an extended lifespan and be the oldest living member of the species as well. (Just don't let Samus Aran get near them...)
[Answer]
One word: bragging.
Sexual selection tends to boost some "proxies" of the real fitness (see red lips). How about exposing your primary survival instrument? How about lensing it with some glass to look bigger?
And yes, humans can expose their brain with the current technology or very little R&D above it. We almost routinely replace damaged scull parts w/ metal or plastic. No, it won't be completely safe, but the beauty surgery or tattoos are not completely safe either.
p.s. I am sure you have to think about some light filtering or at least wear a hat outside. Light is damaging to most tissues and the heat management will be complex.
[Answer]
What you are describing is not that far from [Artificial cranial deformations](https://en.wikipedia.org/wiki/Artificial_cranial_deformation) as we know it here on Earth.
[](https://i.stack.imgur.com/f4lEi.jpg)
Now there can be several reasons for this:
* Religious reasons : Maybe this species believes in a Creator or superior species and wants to ressemble them.
* Social status : A large, elongated brain is a trait associated with nobility. Thus, the members of this species desire to deform their cranial structure in order to achieve this look. In this scenario, the glass dome is here to provide the expected shape.
More technical reasons could be:
* To provide more room for brain growth: This species' intelligence has transcended what its natural body is capable of holding. Their brains are stimulated (either through training or chemical interventions) so much that the cranial structure becomes a limiting factor. Hence the glass dome, which is there to provide some additional space.
* Photosynthesis: to provide more energy to the brain or stimulate cell division
* Or maybe this species has discovered another sense, or developed [brain-to-brain communication](https://en.wikipedia.org/wiki/Brain%E2%80%93brain_interface), and their natural cranium would interfere with it.
[Answer]
Because the brain is the essence of the being, not the body.
When the body wears out, or becomes damaged beyond repair, that species can transplant the brain into another body. The glass is just protection for the brain, instead of bone. This makes transplanting the brain into another body easier and safer. You'll have to decide where these extra bodies come from. It could be clones, a species of lower life form, or even grown to order in a lab/factory.
[Answer]
This used to be a genetic defect. Something like hemophilia in the Romanov Dynasty. Something very rare, killing most people who had the gene until it developed strongly through inbreeding in a royal line. Royalty unlike the peasants could spend their whole life indoors, and would not quickly die from brains sunburn.
Unlike the Romanov this dynasty was as successful as the British. The sun never set on the clear skull empire. Having a clear skull was like actually having blue blood.
The moment the first doctor offered the first procedure to make someone's skull clear, people were lining up around the block. It was a chance to make yourself divine royalty. Unlike the natural clear skulls, this is done with UV proof glass. Anyone could have it and still go outside. Soon this fad exploded and anyone who was anyone had to have the glass plate in their skull.
In modern day the empire has dwindled to ashes. There is still a queen, but she is a figurehead over a parliament. Most colonies are now inducement. Even the royal family has now received genetic treatment for their condition, and children born with clear bones and skin are very rare, and the defect is generally repaired at birth. Still the one thing that remains is that anyone in the middle class and up installs glass domes in their heads. Maybe there is some rebellious youth who don't do it, or get black glass to show that their mind is not exposed to the world. But this tradition is not going away fast.
[Answer]
**They need sunlight**
Similar to Vitamin D, or photosynthesis. The constant diseases and bacteria present on the planet made their skin evolve to absorb much less, and be much more repellent to such absorption, with the downside that it made it much more difficult for them to absorb sunlight through their skins. This lowered their life expectancy -significantly- over time.
By building a glass dome around their brains, they can let the positive sunlight through much more effectively, powering their brains and bodies, while still keeping all the bacteria's and viruses out.
[Answer]
To have advanced conversations with each other, they syncronize their brains together using optical data transfer send and recieve and they hold their heads together.
Your species makes use of cybernetic implants, which gives them 500 terabytes of memory, mathlab, photographic memory, galactic maps and other super-powers. Only issue is, the fastest way to upload and download their brain information to share with other aliens is optical photon data transfer, in fact the top of their brain glows data transfer photons if you smash the screen and hit some of the electronics. Despite being able to transfer information optically by bringing their heads together, and by uploading to the mainframe ports, they are mostly obsessed with galactic dominance and they relish human brains farci/stuffed with a local variety of avocado from their planet.
[Answer]
Emotions are conveyed by tiny fluctuations in the brain's shape, colour, brightness. Just as a minuscule narrowing of the eyes might convey a great deal between humans, a similar scale of change in brain display might convey as much to your species. This subtle visual communication of mood or emotion would very likely be undetectable to other species.
[Answer]
Cartesian Dualism / Religious Fanaticism.
How else would their souls travel to heaven upon the death of the body? Supreme exodus blocked by impermeable membrane is not for those who truly believe. Finally, as a sign of devotion to their creator they bear all so that their minds can be easily touched by god.
[Answer]
Because they simply do not have a skull covering their brains. Their brains aren't just brains but also their sixth sense and require visual openness in order to work. The glass is technological protection against diseases without limiting their sixth sense.
[Answer]
If the effect of the Diseases are visible, then the glass dome could provide an extremely good sexual selection tool, and the species would evolve to consider it attractive - if you want, even the 'glass top' itself could be natural to the species (Although it probably wouldn't be actual glass in that case\*).
This is similar to how humans have come to evaluate symmetric faces as attractive; asymmetric facial features correlate with diseases and other genetic issues. Symmetric features then suggest a lack of such diseases.
If such brain diseases are common, and have been so for a long time, then being able to select partners without such diseases would be a strong evolutionary pressure.
Humans - and most other creatures on earth have evolved thick skulls because that helps protect our brains, which increases longevity and thus increases the probability we will have children. With your species, all you need is for the diseases to be a higher evolutionary risk factor than damaging their brain through physical force -- and evolution will have done the rest.
\*In this case, the species might have evolved somewhat transparent skulls, and considered being able to see brains clearly as highly attractive. And as a result, replacing the top of their somewhat transparent skulls with completely transparent glass could be common practice.
*Some of the older answers have elements of this answer - but I realised they combined very nicely, and wanted to post an answer that pointed that out - hopefully clearly.*
[Answer]
It changes color according to their emotional state, so they make it visible to enhance communication.
"Stay out of Genloo's way. He's been red-brained all day."
[Answer]
**Parasites & Cyborg Infiltrators**
Two possibilities:
1) The species live on a world where parasitic infiltration of the brain is commonplace and essentially unavoidable. To combat this, they routinely have to open up the skull and perform brain surgery to remove some gribbly horror from their grey matter.
To tell when this is necessary, they just added a window. Now they can see the tendrils of the little monsters and know when to visit the doctor, as opposed to being quietly chemically manipulated into a stupor until their friends notice.
2) The species has faced (or is still facing) a threatening race of robots and cyborgs which like to work by implanting cybernetics in the brains of unwitting subjects and using them as meat-puppets. This can range all the way up to replacing the entire brain with an artificial replacement.
Having a window in their skull means it's possible to see these cybernetic enhancements and a lot harder to infiltrate by that means.
In both cases, a transparent skull provides confidence that the person is who they say they are and can be trusted.
[Answer]
I see four possible reasons:
1. **Sex Appeal** If your specie value intelligence above everything else, having your brain exposed could be a way to attract more partners. It's size, the amount of sulci (the crevices on the surface), or some other physical aspect could be directly linked to intellingence in that spiece, making it easy to see who is the better candidate for reproduction. *This doesn't explain why they would do it on a child*.
2. **Identification** In our society, we mostly use facial features to recognise each other. Your specie might have extremely similar features, making it harder to tell members of the same family apart, or people of the same gender and age. Their brain shape and appearence, on the other hand, is unique and they are keen to recognise them. *This could have ramifications on how the criminal enterprises work, to cover it or make it look different*
3. **Medical reasons** Assuming most of those cerebral diseases you were talking about had visible symptoms on the brain surface (more likely in case of parasites), this would make it much easier to get a diagnosis. But a specie so technologically advanced to be able to do this would probably have better and less invasive ways to check. (**Don't forget skulls grow too.** That means that during their lives, especially during their development years, they would need to replace the glass quite often to fit it to the grown skull. It's just easier to do a checkup). *Not very realistic, IMO*
4. **IT'S NOT GLASS** It looks like glass, but isn't. It might be a device to transfer informations: upload knowledge directly to the brain, download memories, even work as medical device to constantly treat the diseases mentioned above. It being a device explains why they go through the operation several times in their lifetime to replace it while growing (as mentioned above), why it's clear (kind of material, or to make it easier to see if it's damaged), and even why it glows (has an energy source, and works just like LEDs on our devices to show they are working properly). *I would go with this. It give them REAL meaning and works for all ages.*
[Answer]
During times of intellectual stress they can absorb brain matter from another individual and use it for their own cognition. They have a regimented social structure that governs how and why this may be done. Certain of their social classes are required to wear signs reading "In case of emergency break glass" in their language.
[Answer]
The race needs constant airflow within brain, both to keep it "fed" with oxygen, and cooled down, due to generations of extensive genetic engineering that caused the race extremaly smart they became incapable to provide oxygen and sustain brain temperature at safe levels without additional surgeries.
Surgeries might consist exposing the brain and adding small organelle able to provide oxygen from atmospheric air directly to the brain.
[Answer]
We humans tend to see what we know in everything. When we see a humanoid head with wrinkled mass pointing out of it we assume its the brain.
In fact, it is a penis, or well the closest to penis we can get. Aliens "shows off" their reproduction organs to find a mate. Also, not sure how many sexes there are but each have their own "brain", that for a human looks the same, but easily recognizible by members of the alien spiecies.
[Answer]
They need, or want, to do repeated laser brain surgery. Having a glass dome would mean they can access the brain without actually having to cut open the skull every time they need to do so.
They might be modififying how the race thinks, or bypassing different brain centers to optimize their thinking. In essence they are trying to evolve faster than evolution lets them.
The reason why it's a repeated process might be because the brain heals itself over time and they need to readjust it constantly or because it's in such an experimental stage that they need to alter things that didn't go as planned to avoid side effects that only show up after a while.
[Answer]
Rule Of Cool. Plus, only the *rich* aliens do this - your average everyday Joe Six-Pack alien can't afford the surgery. And it has to be done after the skull has grown to full adult size - or done multiple times - so a child alien who's got a skull window is definitely the product of rich, status-conscious alien parental units.
[Answer]
Only real advantage is that you can see the brain.
Why would you want to see the brain? Because there is something important that can be seen on the surface of the brain at a glance.
What type of important thing? Since the window is artificial it must be some abnormal condition. Since it can be seen at a glance it must be something of imminent interest to everyone. Such as really scary disease, the transmission of which can be prevented if you see who is infected.
Is there such a disease? Not in real life but in movies with zombies. It destroys mental processes which probably causes visible changes to the brain and spreads by bites so if you forewarned both your life expectancy and control of the disease go up.
Is that possible? Probably, kind of. There are fungi infecting ants and insects that take over the brain and diseases such as rabies affect behaviour and spread by bites.
So just add a disease that infects the brain with visible symptoms (if you can see the brain) and gives its victims a compulsion to attack and bite others so the disease can spread but is otherwise not readily apparent. The infected would be just as cunning and agile as before. They'd just have no interest in things other than biting people. Being able to visually check if others are infected before they come close would have value.
So just add a brain window and nod when you meet people.
[Answer]
Probably a sign of higher order, or something along the lines. Maybe exposing the brain is a sign of truth, versus sheltering the skull, which implied inferiority, for lack of better words. T
[Answer]
Some of the species undergo a surgery to expose their [Pineal Gland / Third Eye](https://en.wikipedia.org/wiki/Parietal_eye) to see more of the electromagnetic spectrum beyond "normal" light.
[Answer]
**These are the descendants of the world we know from Idiocracy.**
President Camacho was injured in a motorcycle accident that resulted in him having to have the glass dome installed. Politicians decided that the surgery would have to be offered to any citizen upon demand because to do otherwise would be discriminatory.
Naturally, as a free government service, the appeal to the average citizen was undeniable and rapidly adopted.
In the generations since, the reason has been lost. Likewise the reason for the lizard tail is lost in the mists of time.
These vanities will disappear when the robotic surgeons finally break down.
[Answer]
A look from the other side: The "natural state" is to have an exposed brain.
Let's say a long time ago, before medicine was advanced, a small part of the population of this species (that had covered skulls at the time) was born with a defect: their skull never closed on top and the brain was exposed to the elements. Mind you, at that time we didn't have so many diseases, so it was something a lot more maneageble.
Strange thing was, people with this "defect" actually lived longer, had better reflexes and had more "intelligence" than the other. Apparently having direct exposure to sunlight was very good for the brain.
Overtime, natural selection ensured that their descendants outnumbered "normal" people descendants and it bacame the norm.
Nowadays they just cover the brain with a glass case to protect it from the elements and all the bacteria present in the world.
[Answer]
Hyper-advanced blood-brain barrier to protect the brain from the bacteria and diseases.
If the “bacteria and pathogens that affect the brain” does so by burrowing through the skull into the brain, then it’s likely that the creatures are selected to use a material that is hard and resistant toward being bored through as it’s skull.
And it just happened that glass, or silica, is one of the hardest, most-resilient-toward-burrowing material that can be deposited biologically—diatoms use it to stop predators and viruses alike, and certain marine animals use it as bones.
So your race uses glass as it’s skull to protect it’s brain from infection as it’s both inert, airtight and water-resistant, blocking out the pathogens from burrowing into it’s brain. The glass may be microscopically porous (less than 40nm in size) in order to exchange air and nutrients with the rest of it’s body, but still small enough to stop bacteria and viruses from entering or trying to burrow through.
The creature’s optical receptors may also be located on the surface of the brain, which function as the creature’s mean of vision, using the glass dome as the lens. The outer edge may bioluminesce in order to provide lighting in the dark.
The race may be able to control the glow, possibly to communicate with others of it’s kind, which may be faster or slower than human speech.
Also, silica is transparent to UV light, which kills bacteria, viruses and other microbes. If they bath in the sun, the transparent skull may also allow some of the pathogens to be killed, further increasing fitness of the creature itself within said conditions.
[Answer]
[](https://i.stack.imgur.com/X9FP8.jpg)
1) Stylo Stylo - For Style , fashion statement.
2) Attract or show off of bigger brain than others.
] |
[Question]
[
I have a race of elf-like humanoids that live in a forest. One of their best methods of travel is what you may call "forest running". They are attuned to the harmonic movement of the forest from a young age, they can predict the movement of branches in the wind and are agile enough to run and leap from tree to tree without crashing to the ground. Every able-bodied member of their society has been doing it since the moment they could climb a tree, and so it’s quite ingrained in their society.
## Available Resources
Since they live in a forest and don’t often trade with other races outside of the forest (at least not until recent years) they don’t really have metal. What they *do* have is wood, resin and a strong rubberlike substance they produce from the cocoon of a creature that resembles a giant fuzzy caterpillar they keep as a pet. The same cocoon also produces a silk-like material. Leather exists but it is costly because they see the working of leather as a lowly occupation.
## The Problem
Now, the problem is that while a projectile weapon is a must for a race relying on agility and dexterity rather than bulk and brute force, I don’t see how they can carry a bow, especially a big enough bow to be lethal against light armor, while tumbling, leaping and flipping head over heels among the canopies of trees. Any unfortunate snag of a branch on a bowstring, any catch of the end of a bow in a vine or some leaves can send a person crashing to the ground in a limb-shattering disaster. The same goes for any normal arrow quiver.
So, what I'm looking for is essentially this:
1. It needs to be a projectile weapon
2. It needs to be small and light enough not to over-encumber a forest-runner, not to snag on branches or foliage and be easy to carry
3. It needs to be quick and easy to draw (so just unstringing a bow and carrying it won’t be enough of a solution. Stringing a bow takes time they don’t have.)
4. It needs to be powerful enough to be effective in battle, at least against light armor.
5. It needs to be achieved without metal, with only the resources they have.
[Answer]
Consider the lowly sling. A couple of lengths of string or leather lace and a pouch, from which one hurls stones or cast shot.
The sling was one of the earliest weapons created by man, and it was used by regular soldiers in warfare as recently as the Spanish revolution. In warfare, the Aztec slings were considered to be as effective as the Spanish muskets.
The world record for distance with a sling is over 700 yards. In medieval and earlier warfare, archers were considered lethal to 200 yards, but slingers were considered lethal to 230 yards. Unlike archers, slingers were effective against armored troops, capable of inflicting internal injuries to the head and torso from sheer energy of impact.
Using the sling is quick ... Load, whip whip whip release.
To a student of the sling, the biblical account of David and Goliath is a classical case of never try to fight a ranged battle with melee weapons.
Slings are easy and cheap to manufacture, typically requiring about 6 to 8 square inches of leather or cloth. Old tongues of shoes are perfect.
**Edit: Ammo Concerns**
A couple of commenters have brought up questions about ammo.
Assuming the elves are comparable in size+strength to a 12 year old human gymnast (based on the ideal size/strength ratio for the kind of agility this lifestyle requires), they could easily handle 10 lbs of shot. Think of 12 year old boys out chasing around the forest with "kids stuff" - lunch, airsoft guns, rope, planks for a treehouse theyr'e building, etc.
A slinger encumbered with 10 lbs of 1 to 2 ounce stones for shot would have roughly 120 shots before having to reload. Their agility would only be slightly impaired.
Shot needs to have a certain mass to be effective, with different shot masses being more effective for different purposes. A 5 lb rock thrown a short distance (say 10 yards) was good for breaking horses' legs, but useless against armored humans. A 1 to 2 ounce rock hurled at much higher speed was effective at longer ranges and against armored humans. Lead shot was used by the greeks and romans to achieve an ideal balance of range and energy of impact (i.e. killing power).
Explosive shot has to have a certain mass, again, to be effective. There is a reason that hand grenades are the size they are - it's to produce enough shrapnel moving at a high enough velocity to do real damage. For reference, grenadiers in the Spanish revolution used slings to extend the range they could throw hand grenades.
Explosive seeds would be much like fire crackers. They might sting on impact and leave a welt, but would be unlikely to be as directly effective as simple stone. However, the noise could startle horses, or they could be used to set off larger planted charges at a distance.
Lower density and softer shot, such as nuts and wood pellets, will never have the range or stopping power of stone or lead shot. Getting hit with an acorn travelling at 80 mph (typical of what a 12 year old can accomplish with a sling) stings pretty badly but is hardly lethal, and something as low density as the acorn will lose energy quickly to air friction so it will have short range. Getting hit in the head, with no or unpadded helmet, by a 2 ounces of soft granite travelling at 80 mph will cause concussion. If the head is unprotected there probably also be a skull fracture, and the shot does not lose much energy to the air so it could be achieved at range..
**Edit 2: Additonal information from comments**
Slings were originally used by hunter-gatherers to bring down small and medium sized game animals, so their accuracy is not in question. However, it does take a lot of practice to develop that accuracy.
<https://www.youtube.com/watch?v=Tpu-BCSfJ2c>
(Credit @Mugluck) The accuracy and stopping power of a sling is approximately equivalent to a .44 caliber hand gun. <https://www.dailymail.co.uk/sciencetech/article-4541318/Roman-sling-bullets-deadly-44-Magnum.html>
(Credit @Mirror318) At release, the shot from a sling can break the sound barrier. At initial velocity of Mach 1+, shot is continuously slowing down until it hits the target, regardless of relative elevation. There is a slight disadvantage to slinging up hill, but no great advantage to slinging from above versus on the level with the target.
**Side note - analysis of David and Goliath from a purely military history perspective**
The confrontation between David and Goliath is mis-characterized, making David the underdog. In truth, what happened is David redefined the entire nature of that war. In the heroic age of military leadership, it was expected that the general would be the toughest fighter, and that the two generals might go toe to toe.
Goliath was looking for a man-to-man slugfest wth the Hebrew general, with the stakes being subjugation. David reframed the discussion as extermination of dangerous vermin, and changed the entire war from one of subjugation to one of survival.
David is often painted as a "wimpy shepherd boy". Based on modern day bedouin culture and the written account he was between the ages of 10 and 20 (he was too young to grow a beard).
From the age of 10, he had lived for weeks at a time in the wilderness with his sling being the only thing between having dinner and being dinner for alpha predators (lion and bear are specifically cited). As a shepherd, he had to manhandle livestock on a regular basis. Before the Goliath incident, he served as a part time armor bearer, carrying 50+ pounds of spare parts for soldiers into the battlefield while being unarmored and unarmed himself. "Wimpy" must have a really broad definition.
So, here is a famous clip that puts it into perspective ...
<https://www.youtube.com/watch?v=anEuw8F8cpE>
Poor Goliath never stood a chance, even if David had been a "wimpy kid" as some preachers would have you believe.
[Answer]
First of all, since you are dealing with forest fighters, you do not need the range of a bow, if your enemies are that far away the vegetation will cover you and you will probably will not see them.
So, there are two readily available options:
## Spear & spear-throwers
The basic spear is limited by how fast the thrower can move its arm. But, with a little help from a [spear-thrower](https://en.wikipedia.org/wiki/Spear-thrower), he can exchange a little more strength for a lot of speed for the spear.
[](https://i.stack.imgur.com/yR2mS.jpg)
Image courtesy of [Wikipedia](https://upload.wikimedia.org/wikipedia/commons/thumb/d/d7/Nativo_do_Novo_Mundo_lan%C3%A7ando_flecha_com_o_propulsor_ou_est%C3%B3lica.pdf/page1-424px-Nativo_do_Novo_Mundo_lan%C3%A7ando_flecha_com_o_propulsor_ou_est%C3%B3lica.pdf.jpg)
Here you have a video of a guy making and using one of those: <https://www.youtube.com/watch?v=rrlr02YDr5A>
## Slings
Another classical options, [slings](https://en.wikipedia.org/wiki/Sling_(weapon)) typically are made of vegetal fibers. You can even "wear" them wrapped around your body when not in use.
For the best effect, the slinger would have selected the best ammo (natural rocks, polished rocks or even ceramic projectiles) way before the battle, but if the need arises he could try to use the rocks available at the place of the combat.
[](https://i.stack.imgur.com/MKI9e.jpg)
Image courtesy of [Wikipedia](https://upload.wikimedia.org/wikipedia/commons/thumb/3/37/Balearic_Slinger.jpg/348px-Balearic_Slinger.jpg)
Here you have the same guy from before making and using a sling: <https://www.youtube.com/watch?v=RzDMCVdPwnE>
A small disavantage is that the slinger can be uneffective if there is not a clearing wide enough to propel it, and that while the spear can be used in close quarters combat, the sling is totally unsuited for that. The sling main advantage is that its range is far longer, and can be very effective against armor (with good ammo).
An advantage of both of those weapons is that they are classical inventions that have been tested time after time all around the world. They do work.
## Plumbata
As a curiosity (since, as its name implies, it breaks the "no metals" rule), the [plumbata](https://en.wikipedia.org/wiki/Plumbata) is a dart weighted with lead. The extra weight meant that at the same speed (which was limited by the speed of the throwers arm) it could get more penetration power.
I have read some stories of those being used to stop armoured knights in the Middle Ages; here you have to take into account that the impact depends both of the speed of the projectile and the speed of the target (if the target is in full charge towards the thrower, the dart will penetrate deeper).
For the other requirements of your question, it has some advantages: it would work well against armour at short ranges and would be deployed very fast (just take one and throw it).
There is way less info about the plumbata, but I found this video: <https://www.youtube.com/watch?v=qPQGBsQAcb0>
[Answer]
Good answers so far! But some do not address your arboreal Elfling's tactics, namely, *tree running*! Using an atlatl or sling high up in the canopy will be impractical due to space limitations. The slingshot and blowgun are, I think, the best of the answers given thus far.
But there are other possibilities.
They have wood and rubber. They also have access to plant fibres and hair (even their own!).
A good possibility is the rubber-powered dart launcher, a sort of combination between blow-dart and slingshot. Just knock a dart, poisoned or otherwise, and slide the tip into the barrel:
[](https://i.stack.imgur.com/XWDso.jpg)
A second possibility is the spear gun:
[](https://i.stack.imgur.com/IeKaf.gif)
These weapons have the same advantage as the arrow: power & penetration. But also, there is the added advantage of being able to wield them within the relatively restrictive parts of the forest canopy.
As for dart & spear tips: those can easily be made from stone, bone, antler, fish scales, wood and of course trade metal. Most of these will pierce "light armor" certainly. In the hands of an Elf warrior, I'm sure they're more likely to penetrate *between the armor* as it were!
[](https://i.stack.imgur.com/9LFFc.jpg)
But, all this being said, I would **not** discount the simple bow and arrows! You don't need a big huge bow. You need power and tactics. Consider some of this fellow's tricksy moves and just imagine what your Elves could do a hundred times better! (Take with a grain or three of salt: I make no claims for historical accuracy of claims. Just to clarify: I provide this as a resource for possible manoeuvres & techniques your Elves would probably find quite basic and simplistic. Others have expressed disagreement with this resource on historical grounds. I take no stance one way or the other in that regard other than to point out what your Elves should easily be capable of with a decent bow in hand.)
[**Lars Andersen's Archery Technique Video**](https://www.youtube.com/watch?v=BEG-ly9tQGk)
[](https://i.stack.imgur.com/KnLEV.jpg)
[Answer]
Slingbows. These are slings designed to guide an arrow accurately through a shot.
[Answer]
**A Slingshot**
You have wood, rubber and resin. A sling shot would be pretty easy to make and you could throw an initiation ritual for the children where they need to find the materials and craft their own slingshot.
Its small enough so you can carry it close to your body and not get it caught, and you can use a variety of different ammunition, ranging from rocks to pieces of fruits or seeds.
It will require less room than a sling and you probably won't get the range of a sling, but its much easier than trying to swing a piece of cloth while your on the move.
[Answer]
IMHO the easiest thing is to look at how humans currently have solved the problem. In this case the simple [blowgun](https://en.wikipedia.org/wiki/Blowgun) is quite effective - especially when combined with locally sourced poisons
[Answer]
Two possibilities spring immediately to mind -
1) Razor sharp flint knives either dropped from a height or using the "whip" of a flexible branch to accelerate their throw.
2) Organic weapons - you mentioned the fuzzy caterpillar. Caterpillar spines are often horrifically irritant to keep birds from eating them. A silk bag full of those tossed in someone's face will make for a world of hurt.
[Answer]
**A Miniaturized Ballista**
The ballista is a weapon somewhat resembling a large crossbow that operates with a torsion spring instead of a leaf spring. As a result they could be drawn so that the limbs were parallel to the stock. While they were designed as siege engines, a scaled down ballista would allow a smaller size than a bow once drawn. Have them carry the ballista pre drawn and you allow for a smaller size and quick usage. For the quiver, you could strap it close to the leg and put a flap over the top so the bolts don't get caught on anything.
Note you biggest problem is going to be making projectile heads capable of piercing armour without access to metal yourself. Wood will likely splinter and stone will shatter.
To contrast some of the suggestions given, here is a comparison. The spring based weapons suggested fall into three categories: leaf, torsion, and tension. Leaf springs were typically used for personal weapons (bows, crossbows). They work by bending a stiff material. This makes them simple, durable, light, and accurate. Torsion springs store energy by twisting something attached to a lever. This was generally used on siege weapons (ballista, scorpion, catapult) since it can be easily scaled up (just add more material to the spring). They are still accurate, but require the additional complexity of one or two pivots. Finally tension springs work by simply stretching back (Slingshots). Biggest problem here is they need very stretchy material. Another issue is the pull is less constrained, you can shift and turn side to side, up or down, which makes it less accurate. A bow can only really turn side to side and even that can be easily minimized, a crossbow or ballista can do neither so there is less operator error to degrade accuracy. One big difference between all of them though is draw length and power. Unless you have a very stretchy material or want to put a turn in the line (not recommended), there will be significant length to the tension spring before you start pulling so you will not be able to have as long of a draw, where as torsion and leaf springs allow the draw to start right at the end of the weapon. Next is the draw weight uptake, tension springs start at zero and gain force linearly, leaf springs also start at zero, but can be designed to gain weight faster at the start than the end, torsion springs can be preloaded to give weight right from the start of the draw. The two factors you want to balance are minimize the force required to use, and maximize the energy available. Since work is force integrated by distance, this is achieved by having as long a draw as possible with as even a force required throughout the draw as possible. This is where tension springs lose. English longbows were often about 120 lbs. draw weight (force required to hold all the way back), matching that power with a good slingshot (rubber expands to say 3 times its length) might mean you need a to draw 170 lbs. which will require significantly more strength. Flip side is slingshot is the lightest, followed by bows, with ballistas being the heaviest.
[Answer]
You could look into darts (blow and hand), yoyos as light blunt force weapons (they were supposedly used as hunting weapons in China and parts of South East Asia as well as Greece), slings or kunai's which are all light, lends itself to the dexterity and speed of your race and small enough to be carried without encumbering them. They would have to strike exposed flesh though this shouldn't be an issue since you mentioned their opponents would be wearing light armor (heavy armor in the forest would be difficult to move in). Coating the blades, stingers, bullets in sticky poison, slow acting acid or anything that they can use to add extra damaging effects would also be good.
[Answer]
I'm going to go out on a limb (so to speak) and suggest something crazy:
**Airguns**
They'd be limited in power without metal, but a wooden pressure tank coated inside with rubber to reduce leakage and wrapped outside in silk and resin for strength could approach the pressure containment ability of a fiberglass tank. Which gets you a non-trivial amount of pressure.
Make the valves out of bone and the seals out of just a little bit of leather. Barrels are made out of silk-wrapped wood. Without metals there's no real way to do rifling, so they are probably break-action and shoot (much larger) blowgun darts with far more range and power than a blowgun ever could. Possibly more power than a similarly-sized bow or crossbow depending on whether the silk in question is (like real silk) as strong as steel in tension.
For an added benefit, the fact that the tank allows pre-battle storage of energy means the tree-runner won't be tiring themselves out operating their weapon and can devote all their energy to running, jumping, and climbing. This would make them seem almost super-human to someone who was used to fighting archers who have to stop shooting to rest fairly regularly.
Add poison to the darts for additional effectiveness.
Edit:
The valving mechanics of an air gun are not particularly complex. Note the bend in the air passage to allow the striker access to the valve stem. The internal spring in the tank is solely for ease of filling a tank from empty and could be omitted. The overall shape developed by your elves would likely be different as they would not be attempting to re-use firearm production toolings. I would expect a fixed valve-stem instead of a striker pin and a direct striking rubber-powered hammer instead of the spring-powered indirect pressure striker used in the diagram, but the shape of the air passage and valve arrangement would be similar.
Picture from: <http://www.beemans.net/images/Austrian%20airguns.htm>
[](https://i.stack.imgur.com/5i11s.gif)
Feasibility all comes down to how good they are at shaping things from their silk and resin.
[Answer]
I would highlight that there are plenty of hunting animals that don't depend on brute strength, but agility and dexterity to capture their pray. As such, your assertion that melee weapons are not suitable is wrong. As such I will answer with what I would do if I was one of these elves rather than how your list of assertions should demand these elves act.
There are plenty of very fast acting poisons in the forest; and these people are likely to know how to collect them since they're so in tune with it. I would then coat my daggers and blow darts with this.
I would then avoid any direct conflict with any aggressor; and just migrate should an aggressor approach the home. Any fighting would be done using guerrilla tactics; waiting for knights to take off their helmets before shooting them with the blow darts or dropping down from above with the daggers.
[Answer]
# Bolas
If you wish to incapacitate rather than kill an opponent [bolas](https://en.wikipedia.org/wiki/Bolas) are a good option. They consist of 2 or more weighted balls/rocks secured with string or cord designed to wrap around the target upon contact. Having one of these wrap around an enemy's legs will cause them to trip and fall, enabling you to get away or allowing for follow up attacks with e.g. short spears while the enemy is downed. If it wraps around their arms/torso they will lose the ability to attack you with their weapon, also conferring an advantage to you, but this would require a longer cord than depicted below.
[](https://i.stack.imgur.com/x8c60.jpg)
Image credit: [Instructables.com](https://www.instructables.com/id/Making-a-Sling-Shot/)
[Answer]
**Chemical Warfare**
Every scout would carry a few vials of poisonous gas, enough to kill or incapacitated anything that breaths 30 meters from where it shatters. You just need to wait until the army hold to rest inside or near the forest and begin to hurl this inside their camp. In a few minutes everyone who survived the attack would end up with their lungs burned and completely blind.
Then you just need a dagger to end the job.
If they are fighting in the forest, apart to set tons of traps, I would recommend a blowgun with poison darts. And use a poison that doen't kill your target, instead just try to make it cause fever and deliriums. Seeing your brothers in arms start screaming at monsters that you don't see in middle of a dark forest full of 'elves' could offer a great moral advantage to your forces.
[Answer]
Just because nobody has mentioned it yet, how about the staff sling?
<https://en.wikipedia.org/wiki/Sling_(weapon)#Staff_sling>
Much like the humble sling but significantly extended range and also power to hit as hard if not harder than a regular sling shot. Reasonable accuracy can be learned in an afternoon and that could easily grow to pin point accuracy with a few days extended practice. The staff can be user preferred length with longer ones increasing range. Other than a sturdy stick for the staff, the materials are identical to the good old sling.
In a worst case scenario where the enemy is closing in on you, you can pull the sling off the end and use it as a regular sling for a final shot before switching to the staff as a club. Sharpen the base of the staff and you have a makeshift short spear.
As the amount of force required to use the staff sling is not that high, you could probably fashion folding or attachable parts for the actual staff to allow increased portability and thus range at the expense of increased preparation time for initial throw. Once the staff sling is fully extended, all subsequent throw times would make no difference.
An alternate approach would be to simply carry a sling and a portable wood shaping tool e.g. knife/axe. When the enemy is sighted, cut the desired size of staff from the nearest tree and with a few minutes of whittling, you can tie your sling to the end of your newly created staff sling. As I am assuming stealth tactics, you probably have the time to do this undetected and unleash a volley or two from afar with fellow elves once you are all ready. If pursued, keep the sling and drop the staff. Make more as and when needed.
Here is a random YouTube video I found featuring a staff sling <https://www.youtube.com/watch?v=0bdoeqRQqAY>
[Answer]
consider the crossbow. D&D has taught us hand crossbows are possible, and myth busters as shown a paper crossbow can be lethal. the have way better materials than paper and a for a weak race a draw back weapon could be useful
[Answer]
A couple of possible ideas that haven't been mentioned yet:
* The boomerang.
These may be seen as toys today, but they were invented as weapons and used very effectively. With a skilled user, they have good range and accuracy, and if you miss they come back to you so you have the problem of running out of ammo.
* The yo-yo
Similarly to boomerangs, we see these as toys today, but they were created with darker intentions. Obviously a fairly short range, but they can be very effective, especially if you equip them with blades. I can imagine these would be used to great effect by your elves if deployed from the branches of the forest down onto unsuspecting enemies on the ground below.
[Answer]
## Disks
Thinks of something between a frisbee and an Olympic discus. Made from hardwood. Thrown fast enough, its mass will make knock out its target (if not kill right away); thrown with rotation gives is stability in flight. Skilled throwers will be able to make it curve around trees and branches. (Of course, you need some clearance, but that's true for all missile weapons -- if your forest is too dense, no missile is going to work)
[Answer]
Projectile weapons are NOT a good option for this and bows, specifically, are even worse.
1) Dense forest means dense foliage making it hard to keep track of your target.
2) Lots of tree trunks. They block your shots, give the target lots of easy cover, etc.
3) Bows actually require a LOT of strength, much more so than swords, for example.
Now, as for actual solutions, I think spears would be your best bet, by far. Spears are VERY good in melee combat, both offensively and at keeping your opponents at bay (specially important since metal is very limited and as such your creatures will not have much in the way of armour), they can be thrown to catch an opponent off-guard or for hunting, they are entirely/mostly wood, they can penetrate light armour with the right tip, etc.
If you really, for some reason I cannot fathom, want a projectile weapon then I guess you could go with the blowgun or the sling. But seriously, don't. Projectile weapons are good in open scenarios, not in the middle of forests dense enough to traverse via "forest running".
Bear in mind that weapons are not used in actual battle 99,9% of the time so most "primitive" weapons have other uses such as hunting, defense against wild animals, etc.
Edit: Just to make it clearer, I mean using a spear mainly as melee weapon. It can also be thrown should it be required but this is just a bonus, not its main intended use.
[Answer]
Another option: rocket artillery. Use gunpowder as the propellant (processed as in fireworks so it works as a rocket motor instead of exploding), a bamboo tube as the launcher and a wooden dowel as the projectile. Small versions are portable for one person.
Drawback: you need to make fire to use the weapon.
[Answer]
Here is another possibility, if they have something like latex. Presumably their rubber-like material doesn't start out like hardened rubber, so you can shape it.
If you can make something like rubber balloons, and if you can fill them with sticky liquidy latex, then you can throw them at people's faces.
Get someone with a good hit in the face and they are blind and they may have trouble speaking and breathing. Maybe they can recover by removing their face armor or head armor, which opens them up for further damage.
It isn't a lethal weapon but it's light weight, compact, easy, and it can take someone out of the fight for a critical time and make them easier to attack. A blind warrior is no warrior at all.
You might try mixing various noxious substances into the latex, but that makes your balloons more dangerous to you if they break by accident. But if you can permanently blind an opponent that's something.
I could imagine packaging them inside freshwater clamshells or big seedpods, and then using half of the container to hold one in a sling or slingshot. It might take a skilled user to make that last work well.
Not your main or only weapon, but a useful one.
] |
[Question]
[
This is a world building question in a preventative context because those people or countries would be left fully functional while others are gone and the safe areas are where the world building would begin.
What countries would be the least likely to get nuclear bombed or have fallout if a full nuclear exchange occurred? With the new massive hypersonic ICBMs that can travel up Mach 20, it would give you only minutes to get to a safe place. So it would be best to just live where it is safe.
Which country has a good economy and be the least likely to be included in World War III directly or indirectly?
Is there an anti-war map or a shaded map showing the safest areas on Earth?
This country has a nuclear war plan that is followed out so there is already list targets in countries that are still going to get a nuking even if they are not directly involved.
The Tzar Bomba was decommissioned in the 60s, but that was 60 years ago and who knows if more powerful nukes have been made.
These links are Google powered online programs used to calculate missile range, nuclear bomb blast radius and fall out:
* <https://nuclearsecrecy.com/nukemap/>
* <https://nuclearsecrecy.com/missilemap/>
[Answer]
**The Vasily Arkhipov scenario, with a twist.**
Many answers have hinted at just how important it would be to determine exactly how the specific scenario plays out, but I haven't seen any take this concept and run with it.
During the Cuban missile crisis, Vasily Arkhipov is often credited with preventing a Soviet nuclear strike and, potentially, an "all out nuclear world war 3" that very likely would have ensued afterward.
So for your world building setup, you'll need to start with a similar situation: competing/conflicting world powers gradually increase tensions until someone goes too far with their posturing and threatening behavior, and the other side feels they have no other option but to launch a pre-emptive strike, but this time there's no Arkhipov on site to stop it.
Which nuclear power is most likely to launch such a strike? Most answers speculate that it would be North Korea, while others mention China, Russia, Pakistan, and the US. NK is, hands down, the most frequently mentioned, for obvious reasons that I don't feel the need to include in my answer. But personally, my money says it's actually the US that launches the first nuclear weapon...at NK...in response to what they believe to be a clear and present danger to themselves from whatever antics NK is up to at the time.
From this point, just work through the responses of all the other nuclear powers. I suspect US would launch a single strike, hoping it will be enough of a deterrent, on its own, to prevent further conflict. But they will also certainly have their finger 'on the button' of many more, just in case. NK will not have any Arkhipov stand-in available and will certainly retaliate, and China will join in, though not "all out" at this point. China will hope to "nerf" the US nuclear capabilities and end the conflict that way, but NK is not likely to hold back anything that the US didn't destroy with its first nuke, they'll launch it all. As soon as the NK nukes are detected, the US will respond with enough to make sure NK has no threat whatsoever left, but will only attempt to "nerf" China in the same manner that China attempted to "nerf" the US. While the US volley is still in the air, the "all out nuclear war" phase kicks off in earnest as China and anyone else that thinks China might win, will send their "all out" volleys at US targets, prompting the US and their allies to send their "all out" volleys in return. But hopefully by this point, some of the initial "nerf" attempts have at least partially succeeded, dramatically lowering everyone's nuclear arsenals, with relatively low impact on civilian populations during that phase. The "all out" phase would see many population centers targeted that the "nerf" phase was unconcerned about, but with reduced firepower the choice of targets would have to be more selective. NK would launch all of theirs before getting hit by the first US nuke. US and China would both be heavily nerfed. Their allies would likely launch most of their nukes before being nerfed themselves.
In the end, only Russia and the US, and possibly China, have enough nukes to strike a relatively large number of targets even after the initial "nerf". US will strike NK and China, and anyone that joins them. China will strike the US and anyone that joins them. I must say I'm not sure what Russia might do, they could pick either side, for a variety of reasons, or they could try to wait till US and China beat themselves up, and then finish them both off (India and Pakistan might also try this type of thing, waiting till the big three pummel each other, and then try to kick them all while they're down).
But the point is that, with the sole possible exception of NK, none of them will be trying to destroy the world, they'll all be trying to make the whole event as tactically precise as possible, and end things as quickly and cleanly as possible, if for no other reason than self preservation, as an uninhabitable world doesn't benefit them in the slightest, and they know that. So primary targets will be nuclear launch capable facilities for the vast majority of the entire conflict, until no one knows of anyone else's nukes that haven't already been launched or destroyed. At that point, the conflict will turn to attacks on other military installations and population centers in retaliation for any missiles that still come in from launch sites that weren't known far enough in advance to be targeted in the "nerf" volleys. But most parties will quickly cease fire when they realize that any missile they launch, and even other, non-nuclear military actions, will be met with nuclear retaliation against their biggest, still-standing, population centers.
When the dust settles, the devastation will indeed be massive, and widespread. The fallout will certainly be a major issue. But because of the tactical precision from most of the missiles involved, and the targets selected, there will be large areas of the planet that are, relatively, unaffected. Nowhere will be entirely untouched, certainly, but there will be plenty of reasonably intact land to go around.
Personally, I'd pick rural inland Brazil, but the area surrounding Lake Victoria in Africa would also be good for similar reason to my selection of Brazil:
1. These are climates good for agriculture, and which are likely to remain good climates for agriculture, even with mild cooling of the climate from nuclear-winter-like effects. (At this point I'm operating under the assumption that, for whatever reason, nuclear winter will not be so severe that your story fails to have a starting point at all). The choice of what to plant might have to change with the climate, but that's true of anywhere in the world.
2. Political stability before the nukes is not likely to be relevant, as chaos will ensue, worldwide, and it's very unlikely that any currently existing country will remain intact in the aftermath. The world will be reduced to city-states and barter systems, if not worse, so whoever is in a particular region is not likely to be able to migrate far, at least initially, and is not likely to care what another group of people even a meager 100 miles away is doing. They'll be interested in sustaining themselves, and cooperation for survival with anyone else in their local area is as good a reason to form a clan/tribe/etc. and get to the business of making food for their new community. No matter where you end up, it's going to come down to luck of the draw whether you end up in a group that decides to farm, a group that decides to hunt, a group that decides to loot, etc. So the original government of the area isn't really a factor to consider. Instead, potential food productivity of the land is likely to be the deciding factor for if and when a region regains some semblance of civilized society, so getting to such an area in advance is your best bet for finding the higher number of farmers to cooperate with and the lower number of looters to contend with.
3. They are not likely to be significant targets in any phase of conflict, and are not likely to be downwind for fallout of any significant targets during any phase of the conflict. Sure, they might have alliances, allegiances, treaties, and agreements, with parties on either side, but they don't have any strategic or tactical importance in the actual nuclear aspect of the conflict. Again, nowhere on the planet will be entirely immune, but these two places should receive the lowest portions of both direct and collateral damage.
I just picked Brazil, over Africa, because I'm more familiar with it, and I suspect its agricultural potential to be even greater than that of Africa (though I admit that could be a misconception based on my own bias).
[Answer]
New Zealand. Nowhere in the southern hemisphere is a likely target for nuclear weapons, but New Zealand is further south than any other countries except Chile and Argentina, has a stable economy and government, a temperate climate, and is self-sufficient in food. It’s also far enough from anywhere else that it’s unlikely to be swamped with refugees from further north.
[Answer]
They say a picture is worth a thousand words, so I'll add three.
North Korea is the most likely country to start throwing missiles around. This is the map of the range of their ICBM's:
Let me highlight a detail:
Brazil is a country that is neutral on every major conflict, with important ties to all sides. Being outside the range of the first wave of missiles, it will have the most land where you won't die of radiation poisoning in minutes, so that's where everyone will go for the final battle of sticks and stones as predicted by Einstein.
To summarize in an image:
[Answer]
Europe, North America and Asia will get bombed into oblivion, or covered in thick nuclear fallout.
Most countries in Africa are underdeveloped and would quickly collapse into chaos and anarchy, or a tighter dictatorship or military rule than what exist as of today. And they'll get some bombs lobbed at them by the virtue of having military bases from the nuclear power presents all over the continent.
Most South American countries are already teetering on the brink of anarchy, not a good choice.
Australia would probably get a few 'stray bombs' just by virtue of being allied with the US or Europe, in order to deny any surviving government a potential shelter there. Which means that New Zealand is likely to get nuclear fallout, if not a couple bombs as well, for the same reason than Australia would.
Which leaves the less habitable parts of the world: Greenland, though winds and water current would probably carry some nuclear dust over it, Antarctica, but getting there is a journey in itself, and you cannot live here, or some island in the Pacific or Indian Ocean.
But, basically, in a WWIII nuclear exchange, no country will be spared, whether it gets some nuclear missiles lobed at it or through the consequences of the bombing and the utter collapse of anything global, from the economy to the internet to the international shipping lanes.
No country would be left fully functional following such a massive bombing. Everything would have to be rethought to take into account that supplies from the rest of the world are gone.
Middle-East would become a nice shiny mirror, which means that fuel would become extremely scarce. Most rare earths and minerals would become unavailable because the mines will be in radiation zones or inaccessible for some reason. The factories in Asia that produces most of the technological stuff that we use everyday will be vaporized or glow in the dark, thus no more new stuff and no spare parts to fix the old stuff.
And I'm not even talking about the panic that would instantly spread through the population of the world once the news spread that nukes have been launched or have began falling on various places over the world.
Basically, even a country spared the nukes will need to have a strong and level-headed government, a calm population, and will have to basically invent a new way of life to cope with the instant disappearance of all the supplies it was getting from the rest of the world.
[Answer]
On top of [Raven Rock](https://en.wikipedia.org/wiki/Raven_Rock_Mountain_Complex). As the quote of disputed origin says, "the living will envy the dead."
More seriously, it is an interesting question exactly where the remaining Cold War arsenals are targeted today. And how big those arsenals are.
The weapons can be classified as [deployed, stockpiled, and retired](https://fas.org/issues/nuclear-weapons/status-world-nuclear-forces/). A deployed weapon is just that, on top of an ICBM or SLBM or waiting to be put onto an aircraft. A stockpiled weapon could only be launched if a delivery system was found, which could be difficult in the chaos after a nuclear strike.
The nuclear powers would have to consider the possibility that key enemy targets are covered by workable missile defenses. To pull a number out of thin air, assume that a place like Offut or Kaliningrad is going to be targeted with half a dozen warheads in the hope that **one** gets through. If **all** get through that increases the local fallout, but perhaps not the death toll -- the second hit just rearranges the debris.
Call it 3,600 warheads on 600 cities or bases. This might include the big metropolis of [Thule](https://en.wikipedia.org/wiki/Thule_Air_Base) or [Petropavlovsk-Kamchatsky](https://en.wikipedia.org/wiki/Petropavlovsk-Kamchatsky) for all we know.
With that in mind, the entire southern hemisphere might get away with just a handful of targets, and of course the fallout. This fallout will be **bad** but not on a scale to end mankind.
[Answer]
As others have pointed out, countries are targets. The sea is not. So the best option would be to get yourself a large ship, a crew and enough supplies to sustain for a few years. As long as you stay away from land (and don't pose a threat to nuclear powers) you are relatively safe from direct hits and you can move away from nuclear clouds coming your way.
The nuclear war probably doesn't last long, everyone will want to fire fast. Waiting risks your nuclear strike capability being taken out. Even nuclear submarines will want to take out enemies early, as leaving them risks giving the enemy time to fire on your own country.
When the war is over, you need to evaluate your options. Luckily, you have that big ship to move around at sea.
[Answer]
I'm staying at home, a few km from the Pacific coast of [Vancouver Island](https://en.wikipedia.org/wiki/Vancouver_Island) - at one point in the 1960s, an American military study suggested that it could be a good place to be (although that could be just folklore). I figure that since the prevailing westerly winds carry the air across the expanse of the Pacific Ocean and keep our air quite clean (if they carry on after a nuclear incident like this), and Canada is a fairly stable government.
[Vancouver](https://en.wikipedia.org/wiki/Vancouver) and [Victoria](https://en.wikipedia.org/wiki/Victoria,_British_Columbia) would likely get a nuke, since they have harbours and are fairly large, but the mountains between where I live and those cities would protect from a lot of the direct radiation from these events. And I like it here too :)
[Answer]
The center of Africa, counterintuitive as that may be.
You arrive at this through exclusion.
1. You want to not be in anything that is a primary target. Any major city of any nuclear power is out, as is anything near a military base in those countries.
2. The next charge of warheads will be targeted at allied countries and secondary military targets. Ports, power plants, major industrial or railway hubs, airports.
That means that Europe is out completely (too many NATO members, two nuclear powers, and everything is close enough together that if nukes fall on all the primary targets, the areas inbetween will be down as collateral damage).
It means east and west coast in the USA are history, as are the major cities in Russia and China. Australia and New Zealand are US allies and will certainly get a couple nukes. As will the middle east, to eliminate oil and because there are both US and Russian/Chinese allies there.
Asia will be toast thanks to having no less than 5 nuclear powers (Russia, China, India, Pakistan, North Korea).
South America and Africa are the continents most likely to get only a couple stray nukes. Of these, South America has the more challenging climate, the closer proximity to the USA and the higher dependency on outside connections.
Africa has fewer industrial centers and is generally regarded as a backwater place not worthy of attention. However, the place is so friendly to humans that we evolved there, strongest evidence you can get. And the people of Africa are used to making do with whatever is there. Improvisation is a major talent that will be in high demand after a WW3 scenario.
You want to be in the center because the major ports and cities that may or may not get a nuke just because are mostly at the coast. You also want to be away from waves of refugees which may come likewise arriving at the coast first. Somewhere in the mountains, near a fresh water source and with farms around would be an ideal location.
[Answer]
TL;DR: It depends on what you mean by "all out nuclear war", and whether or not you plan to remain in the same place post-war... but generally speaking, the farther north or south of the equator, the better, with both the north and south poles receiving the lowest exposure over time due to more self-contained wind patterns. Politically speaking, it's really anyone's guess what might happen, so I'd say you have creative free rein on that.
As for physically surviving the weapons themselves, consider this: by 1962 (after hundreds of above-ground tests conducted by the US, USSR, UK and France), there was no place on the surface of the Earth where radioactive isotopes from nuclear weapons could not be found, thus prompting the first international treaty to limit testing in 1963, followed by the "SALT" talks in the 1970's.
So if you're talking about the "mutually assured destruction" scenario from the time of the Cold War, where literally thousands of nukes would explode on the same day, then the dispersion of radioactive material would be so immense that no place on Earth would be even close to "safe" for many years, possibly even resulting in the fabled "nuclear winter" scenario (nobody really knows for sure). An "all out nuclear war" today would likely involve far fewer, but they are also likely to be far more powerful weapons, thus producing higher local damage with less global fallout. Either way, if any combination of the major nuclear nations today engaged in an "all out nuclear war", it's pretty safe to say that a very large portion of life on Earth would be extinguished within about 6 weeks time, mostly due to the global dispersion of neutron-active isotopes. Of course, due to the enormous number of people on the planet, there would still always be some survivors living in pockets here and there depending on their local geographies and prevailing winds.
There are two primary radiation risks. The first is the the instantaneous (speed of light) exposure to the immense energy released by each blast. This is full-spectrum electromagnetic energy, from long-wave, to infrared (heat), all the way through the visible, x-ray, and even gamma rays. The exposure to this would generally have the same devastating impact on all life forms above sea level that are not at least partially protected by very significant barriers like mountain ranges. (Some x-rays and all gamma rays would still pass through mountains, but the lower frequencies will not.) The intensity of exposure will depend on distance. Line of sight exposure drops off at the rate of the inverse square law (at double the distance, one receives one fourth the intensity; at triple the distance, one receives one ninth the intensity, etc.). If a human is exposed to this direct radiation and they survive the blast, they may have severe burns, or extreme dermatitis which may still kill some in the first hours or days. Marine life would be minimally impacted by the initial blasts, affecting only that which is close to the explosion.
The other risk is, of course, the fallout. It would affect all surface life that receives it. It would affect marine life as well, with the worst effects in the shallow regions and less so in the deep. There are many factors that affect the amount of radioactive particles that get ejected into the stratosphere, among them the proximity of the detonation to bodies of water and the altitudes at which the individual weapons are detonated. Most of the deadly radioactive isotopes created by a nuclear explosion are very heavy, and would gradually, but slowly, sink into the ocean depths, but losing their effect over time.
Radioactive isotopes decay at roughly a rate of a 7:10 ratio between time and intensity (for each 7x increase in the amount of time since the blast, the radioactivity of its fallout decreases by about 10x), but the bigger the blast, the more of those isotopes are floating around in the first place and eventually it all settles on the ground. Most estimates speculate the lethality of any particular bomb's fallout to last on the order of months, but of course, the areas closest to ground zero will receive the greatest volume of fallout and will remain dangerous for a longer period of time.
Bottom line: there are such a large number of variables affecting survivability that for your world-building task, a tremendous range of outcomes are plausible, which gives you a lot of wiggle-room to create it the way you want. In order to minimize the overall threat, my advice would be to focus on dry mountainous regions located at latitudes greater than 30 degrees either north or south, with locations on whichever side of the mountain range receives less precipitation. At between 30 & 60 degrees of latitude, the drier side of the mountains would typically be the East side, and at even higher latitudes, the drier side of the mountains would typically be the West side.
Best of luck with your project.
[Answer]
I'm going to post a bit of a counter-intuitive answer: it's not going to be nearly bad as you might expect. Sure, billions of people will die. But most countries aren't getting bombed.
You might have this image of 'missiles flying everywhere', and every major population center getting destroyed... but that's really not realistic. There are only a handful of nations in the world that have nukes. So unless your country has angered one of them to the point where they want to slaughter your people 'just because', you're likely safe from being targeted. After all, just because the US, China, Russia, India, Pakistan, and Korea are all launching nukes at each other, why would any of them be launching a missile, at, say, Peru? Even if you say, "Well, what about Nation XYZ? Their leader is flat-out crazy, and will just want the world to go down in flames." Ok - but how many nukes does their country actually have? Sure, Korea might have a crazy person at the helm, and they might do something silly like bomb Australia or Canada for no real reason... but they're not going to be able to bomb *everyone* by themselves.
If it helps, think of it this way: we've detected missiles coming in from Russia. We're sending missiles back at Russia. Why on earth would we decide, 'Hey, why not nuke Italy while we're at it? Let's launch a few at Rome just for kicks!'
Short answer? I think we'd have a pretty substantial climate shift, and a lot of areas of the globe devastated... but we'd also have large portions of the globe where life would continue on.
[Answer]
Either Africa, South America or British Columbia in Canada. Africa and South America are both dry spots as far as nuclear armed countries. Of course, the farther south, the better, less chance of radiation. Canada is too close to America to be useful for the most part, but B.C. or Nunavut might be far enough North to manage. Greenland is also a pretty good choice, surprisingly. Australia also has a good chance of surviving, but may get nuked just because its a large enough country.
So all and all, the farther south you are the better, since anything in the northern hemisphere is most likely going to be completely destroyed by radiation polluting the trade winds. Greenland may fair better than most countries, but Chili or other countries on the southern tip of south America are the best bet for survival.
[Answer]
Contrary to popular conception, there aren't enough nukes to "destroy the world", as in, the surface of all landmass on Earth. There are enough nukes, however, to destroy *civilization*, or *cities*. So, in the middle of nowhere, far from major cities, anywhere on Earth, is far enough to survive the bombing.
So, the hotspots will be the (former) cities. You won't be able to live there. The next concern is fallout. Because of global winds, it will be blown *everywhere*.
[](https://i.stack.imgur.com/axxFQ.jpg)
However, this isn't a big concern; even with radiation and fallout, life will still thrive: [Wolves, eagles, and bison freely roam Chernobyl three decades after the nuclear disaster.](https://www.ranker.com/list/strange-chernobyl-radioactive-animals/cynthia-griffith) You'll still be able to live into your 40s or 50s before the cancer overwhelms you; long enough to see your grandchildren if people start marrying at 15 again.
So, just get a good 50 or 70 miles from any major city, and you'll be as fine as anybody else on the planet.
[Answer]
All of the nuclear powers and countries possessing nuclear weapons are in the northern hemisphere (US, UK, France, China, Russia, India, Pakistan, NK, Israel). Their main rivals are also in the northern hemisphere. In a large scale nuclear war it would be expected that the nuclear powers would first strike at their enemies and those in military alliances with them. Most of them would still be in the northern hemisphere, some like Australia and New Zealand are in the southern hemisphere and would probably get involved by defense arrangements between them and UK via the [Five Powers Defence Arrangements](https://en.wikipedia.org/wiki/Five_Power_Defence_Arrangements). Also South America is linked to the US with the [Rio Pact](https://en.wikipedia.org/wiki/Inter-American_Treaty_of_Reciprocal_Assistance). From the southern hemisphere only Africa lacks strong ties to any nuclear powers.
Why does this matter? From any nuclear bomb most of the radioactivity is anyway deposited near the explosion as larger the particles are the faster they fall to the ground. Only a very small fraction that is in small particles that are lifted very high to atmosphere can travel far. Due to wind patterns this will take weeks to travel along latitudes around the globe and months to spread along longitudes within a hemisphere, but [it will take over a year to spread to the other hemisphere](http://acmg.seas.harvard.edu/people/faculty/djj/book/bookchap4.html) (Figure 4-12 in the linked material). So as most of the bomb will explode in the northern hemisphere be at the southern. From the southern hemisphere Africa is the least likely to get involved.
**TLDR; Be in southern hemispheric Africa.**
[Answer]
## Targets
[The two major nuclear powers](https://en.wikipedia.org/wiki/List_of_states_with_nuclear_weapons) are the USA and Russia. Other — relatively minor — nuclear powers are the UK and France (US allies as well), China, India, Pakistan, Israel, and North Korea.
In an all out nuclear war, all these countries are primary targets.
Under NATO's [nuclear sharing policy](https://en.wikipedia.org/wiki/Nuclear_sharing), Belgium, Germany, Italy, Netherlands, and Turkey have American nuclear weapons available as well. It is believed Saudi-Arabia has a similar deal with Pakistan.
Other countries may not have nuclear weapons themselves, but may be strong allies to primary targets — NATO comes to mind.
Because of this, North America, Europe, and most of Asia will either be direct targets or close enough to targets to make life difficult to say the least.
Australia and New Zealand are not NATO members, but are NATO partners and will likely be considered allies of the USA and Europe by the enemies of those, so they may very well be targeted. However, both New Zealand and Australia are sparsely populated. There are a few major cities that will likely be targets, but a lot of almost empty land around them. This sets them apart from other targets.
Canada is a NATO member and a such a target, but is like Australia and New Zealand sparsely populated outside the major cities.
## Non-targets
South America nor Africa is a target for any of the nuclear powers, except for the odd army base. But those would probably receive a single hit, not a nuclear barrage.
Maritime Southeast Asia (the southeast of Southeast Asia; basically Indonesia and the islands around it) would probably not be a target either.
## Fallout and Nuclear Winter
It is quite likely that fallout and nuclear winter will make most of the northern hemisphere uninhabitable. So while Canada may have offered a fair chance of survival initially, the longer term outlook is far worse. The same goes for northern Africa.
## Chaos
Not all states (of the ones left) have a stable government. Some are only able to remain in place because of support by one of the countries listed as targets.
Then again, you may be able to use the chaos to your advantage. But be aware of it.
## Conclusion
Southern South America, southern Africa, the Australian outback, or possibly New Zealand.
[Answer]
I'd say Switzerland. It's neutral and has nuclear shelter capability for all its citizens.
[Answer]
You want to be as far away from any major city as possible.
Even if the city is not targeted, any disruption of food distribution will doom our major cities and just about everyone in them. As soon as everyone knows the hammer is going down, they will head straight to the nearest place where food it stored or sold and loot all they can carry, and come back until the food is all gone or they think they have enough to ride out the storm.
Once the looting is done, there will be roving groups looking for stashes of food. Some of these groups will claim some kind of authority, while others will be robbers without pretense, but their *modus operandi* will be the same: they'll take whatever they can carry off.
The police who aren't directly participating in the looting will be overwhelmed and ultimately ineffective. Fire services will cease in short order, so fires will rage unchecked in many places. Hospitals will eventually shut down due to looting and a lack of supply.
As food dwindles, the people who survive will remember that lowering the denominator will increase the quotient, so there will be struggles to exclude more and more people from receiving any share of the remaining food.
Law and order will have completely broken down in the first week, but it will eventually be restored when there are no longer enough people alive to do any fighting.
[Answer]
Primary targets will depend on who, where, and why the bombs start flying but if the world's current nuclear powers empty their arsenals nowhere is going to be safe. If you're not a direct target then you will get caught by either the global fallout of highly radioactive particles or the temperature drop caused by the soot from burning cities and vegetation intercepting sunlight.
There could be as much as 5 years between growing seasons while the atmosphere cleans itself of particulate matter. Most countries have a year or so of food as a strategic reserve, no country on Earth has food reserves for 5 plus years. There will be food riots and starvation anywhere where a reasonable percentage of the population are still breathing.
Note that the real radioactive fallout will be worse than any of the models I've ever seen; none of them take into account how many nukes are aimed at nuclear targets, either known enemy weapons facilities or known active reactor sites. Each hit at such a site will vapourise literally tonnes of radioactive material and spread it on the global winds of the upper atmosphere.
] |
[Question]
[
**Closed**. This question is [opinion-based](/help/closed-questions). It is not currently accepting answers.
---
**Want to improve this question?** Update the question so it can be answered with facts and citations by [editing this post](/posts/118295/edit).
Closed 5 years ago.
The community reviewed whether to reopen this question 1 year ago and left it closed:
>
> Original close reason(s) were not resolved
>
>
>
[Improve this question](/posts/118295/edit)
In the world I'm writing about, nature spirits such as dryads and nymphs are real. I want them to appear undressed to those humans who encounter them. In the course of the narrative, one of the dryads is asked why she doesn't wear clothes, but I cannot for the life of me come up with a valid reason why these beings would be naked.
Other supernatural beings such as gods or demons can be dressed without going shopping, so nature spirits should be able to wear whatever they want, too. So why don't they?
Why do they *choose* to appear naked? Or why were they *created* that way (by whichever god or goddess made them)? Or why do humans *see* them that way?
---
It is not an erotic story!
[Answer]
The nature spirits are just that- spirits! They have no fixed material form, and instead appear as an idealized, natural version of whatever entity is encountering them. To a human, they appear to be beautiful humans wandering through the forest *au naturel*. To a bear, they would appear as a bear clad with an ethereal glow. And so on and so forth.
I imagine the dryad might answer the question posed to her by saying something like, "This how you came into my world, and thus it is how I came into yours."
[Answer]
Bears don't wear pants. Squirrels don't wear shirts. The trees don't wear hats. Why *would* a physical embodiment of the natural world wear clothes? Clothes are a construct of human society, and spirits simply have no need for them. Clothes aren't natural, so it makes perfect sense that a nature spirit would shun them.
Otherwise, where do you draw the line? Pretty soon you'll have forest nymphs in spandex jumpsuits rolling around in Hummers, throwing their empty GMO hot dog containers out the window.
[Answer]
Because they’re nature spirits.
Clothes are manufactured, in their earliest incarnation using the pelts of dead animals and various bits of dead plant. Why in the world would a nature spirit clad themselves in such things?
Later on you get into the petrochemical industry which is astoundingly *even worse*.
You can consider it a form of sartorial protest vote. They don’t see why they should clad themselves in dead things and know full well that if your body is capable of growing its own plants you need better personal hygiene, so instead they remain naked, as nature intended.
[Answer]
I can think of some options off the bat:
* No concept of a nudity taboo, if nudity is a non-issue in nymph society then cloths are going to be ignored as unnecessary and or strange.
* No need for shelter, if nymphs etc... as somewhat magical beings don't feel the cold, or the heat, then they don't need any form of shelter from the elements, clothing is therefore pointless.
* Natural state for natural beings, clothing would prevent nymphs from being truly in touch with their environment, a fate worse than death if they're forced to endure it too long.
* Clothing as a symbol of artifice, cloths are made things, humans make things nymphs live in the world as it is they don't need to alter the world to suit them, they avoid clothing and other visibly constructed possessions on principle.
* People can't see their clothing, human lore concerning nymphs says they're nature spirits so clothing and other manufactured goods are at odds with our concept of such creatures. Since nymphs have no "real" physical form in our world and what we see is filtered through what we "know" about them and to quote Terry Pratchett "everyone who knows anything knows" that, in this case, nymphs don't wear cloths then we can't see the cloths they do wear. This filter that keeps humans from seeing the true nature of fairies etc... is often called fey glamour it has a long history in folklore as well as genre fiction.
[Answer]
"Why do you wear no clothes?"
"Precisely because you ask the question. It is in my nature to embody nature, yes, but also to steward it, guard it, and indeed *invoke* it. You ask the question because you are discomfited. You are discomfited because something animal inside you moves. It moves because I present myself to you like this; bare and dangerous to your sense of normalcy. What sort of nymph would I be if I caused no more animal urge in you than a man baking bread?"
In other words; characters often make choices based on who they are, their needs or norms, but they may also make choices based on the reactions they wish to see in others.
[Answer]
**Are we not all naked?**
When asked about clothes, the nymph has no idea what you are talking about. She cannot see your clothes either. When she looks at you, she sees your aura - your representation as seen from the vantagepoint of the nearby plane she inhabits. You are always naked under your clothes. She can see other aspects about you that you might think are concealed as well - perhaps also concealed from you.
[Answer]
Because being naked is natural.
Over 95% of all organisms that live or have ever lived on the planet have not worn clothes. If nature is the norm for determining what is natural, then naked would be natural.
[Answer]
"Why would I wear clothes?" the dryad asked. "I don't get cold any more than this oak would shiver on a brisk spring morning. My body holds no shame for me - I have no reason to hide it. And while I pride myself in who I am, my body doesn't threaten anyone else, so I have no cause for modesty. If my body evokes passion in another, that, too, is delightfully natural. I need no silks to communicate wealth, which is a wholly material thing, nor do have I any need of sigils or symbols to communicate a trade, or a marriage. I've never had any urge to wear clothes to express something about myself - but even if I did, nearly all clothes come from the despoiling of something that lives, be it fiber from my friend the oak here, or the skin of a bear or rabbit. I no more begrudge humans the need to wear clothes than I begrudge the wolf the need to eat, but if a creature like me were to drape myself suchly, it would be crassly macabre, even if the components were scavenged from living things already fallen."
[Answer]
* They don't need it: they are supernatural spirits, and don't feel cold or hot. they don't need protection against element, as it doesn't affect them as it do to us.
* They represent nature: a reindeer in suits will be quite odd, isn't it? well, a mermaid to. They represent nature and freedom, clothes are a human thing, representing human society, not nature
[Answer]
Two simple reasons:
1. Because creating clothes requires knowledge of weaving or some other means of manufacturing the clothes, and dryads do not know how to use tools like humans.
2. Because the creation of clothing requires the abuse or destruction of nature, and that goes against the moral code of a nature spirit.
[Answer]
>
> one of the dryads is asked why she doesn't wear clothes
>
>
>
Dryads often are depicted as merging into or entering their associated trees. You can simply say that they can't take the clothes with them. Because they'd constantly have to take off their clothes to flit into their tree, they simply don't bother.
That said, that may not be the initial answer. That assumes the dryad knows what clothes are. A dryad in the deep forest may not be familiar with the concept of clothes.
Reasons a dryad might not like clothes:
1. Prevent merging with her tree.
2. Scratch or itch.
3. Too hot.
4. Can't feel the breeze/sun/rain/whatever.
5. What kind of a freak wears dead plants and animal skins?
6. Is she not more comely than the clothes?
7. Why bother?
[Answer]
From a human-centric point of view, you are asking yourself why nature beings are humanoid but naked...
But from a god-centric point of view, and conveniently taking as reference we are an [Image of God](https://en.wikipedia.org/wiki/Image_of_God), you should not say a being is humanoid, it is a term used for quick understanding and to aid our minds to get a better picture of the creature.
Also you should consider asking yourself, why and when humans started to use clothes. First reason was protection, then power and belonging. Also envy and jealousy were vital for clothes to evolve into fashion.
The point is you could say nature creatures were also created by god or gods as god-like creatures.
Then they were protected to avoid falling in same temptations as humans, or they are incapable of doing things worth falling in disgrace of god(s), so they had never being taught about embarrasment and inferiority feelings because of being naked. And also they might have tree bark or some other physical protection so they've never felt the desire to artificially protect themselves.
Making things to aid ourselves, to expand our possibilities, to make us feel safe, to counteract our handicaps, those are "human" traits.
A driad capable of understand the above would be sure clothes are a proof that humans are lesser beings.
A wiser driad would understand that human adaptability is a dangerous and/or worth-respect ability.
[Answer]
Because nymphs and dryads are emotion or spirit imbued, otherwise inanimate, they don't have the power to create, only to be. A braid or stitch and the power to create one are sacred and only given to humans and gods. Wearing the fauna is the best they can do...
Deep enough?
[Answer]
Clothes are possessions. Nature spirits don't have possessions they keep, or initially even the concept.
] |
[Question]
[
A quadruped the size of a mountain tiger which never stops moving, even in their sleep they walk and wander around.
What benefit would the animal get from wasting so much energy moving every minute of its life?
[Answer]
### Walking aids (or is) its blood circulation
Ever sit down and when you get up your feel a bit light heated, or get pins and needles in your muscles? The cause is imperfect circulation. Once you start moving everything recovers pretty quickly. Let's crank that up. Your animal has such poor circulation that it needs to walk to circulate its blood
One choice is the animal *can* stop, but if it stops, muscles and brain become under oxygenated. Maybe not enough to be directly fatal, but enough that it's in pain, cant react to a threat and cant make sensible choices for several hours. Walking helps aid in circulation.
Alternatively if you crank this up to the extreme, the animal has no heart, just "one way" valves in the arteries. As the animal walks the blood is circulated. The space occupied by the heart can be used for other things.
[Answer]
**The ground is very hot**
[*Gotta keep on movin'*](https://youtu.be/cy46iOwWQiE?t=36) - (click for sound)
[](https://i.stack.imgur.com/78dBE.gif)
[Answer]
Their breathing doesn't use lungs with its inhale/exhale bidirectional flow as most land animals, it is instead built around a one way flow system, like it happens with sharks gills.
Coincidentally sharks have to continuously move to stay oxygenated. It can be more efficient because it doesn't "waste" any time with pushing out used air, but on the other hand it doesn't allow to stand still for long times.
[Answer]
**It is seeking something.**
Dolphins sleep with half of their brain at a time.
<https://www.scientificamerican.com/article/how-do-whales-and-dolphin/>
>
> While sleeping, the bottlenose dolphin shuts down only half of its
> brain, along with the opposite eye. The other half of the brain stays
> awake at a low level of alertness. This attentive side is used to
> watch for predators, obstacles and other animals. It also signals when
> to rise to the surface for a fresh breath of air. After approximately
> two hours, the animal will reverse this process, resting the active
> side of the brain and awaking the rested half.
>
>
>
So too your tiger. It is sleepwalking, in a way. It is moving, and it is smelling. It is not alert; this creature has no natural enemies. Its environment does not pose a lot of dangers. It goes around things in its path. It is more or less walking in a straight line while asleep.
If it smells what it is seeking, its dreams will change and it will wake up.
I could imagine that there might be very few of these creatures and they are spaced far apart. The male will have to travel far to find a mate. That is what he is seeking as he sleeps. That is what he is dreaming about.
---
This is such a cool idea. What if these things sleep all of the time? One arrives and walks through the village and people clear the way for it and watch it as it goes. What if they sleep for years and years as they walk, dreaming? What are they like when they wake and re-enter the world?
What if it is the same one, walking and walking in his sleep, because he is the last one?
[Answer]
Because the plants they eat are so devoid of nutrients, or so rare, or so inefficiently digested that the animal has to constantly be grazing in order to get enough food to survive. They benefit from living where no other animals their size can and by eating a food they have no competition for.
This isn't far from being real life. Many grazing herbivores spend huge portions of their life ingesting food, not 100% but an animal that does have to graze all the time is not beyond imagining.
[Answer]
So it doesn't die of the cold.
There are insects in the desert that need to stay cool by constantly running. They eat running, have sex running, avoid enemies by running, etc. However they are small, and your creature is much larger which means it loses heat slower.
Your mountain tiger is living in cold climates. Large predators normally rest most of the day to conserve energy so having a tiger-like creature spend most of its day on the move would mean it's doing two things:
1: have one of the highest hunting success rates in the animal kingdom.
2: only hunt tons of small creatures it can eat while on the move.
The cold climate is important. This means that the tiger needs to keep warm by moving. Normally such a creature would have evolved a fur coat to stay warm, but if other pressures forced your creature to quickly adapt to the mountain it could have learned to keep walking to stay warm.
Is this likely? No, but it's the only reason I can think of to stay moving.
[Answer]
Your creature has lungs but no dedicated muscles to drive them--the muscles moving the forelimbs serve double duty. The breathing cycle is accomplished by moving the forelimbs forward and back. Your creature must have two openings for respiration, either each lung has it's own access, or the lungs are a pass-through design, one opening for inhaling and one for exhaling.
The creature can stop only for as long as it can hold it's breath. The positioning of one or both of the breathing orifices precludes lying down and waving it's limbs.
[Answer]
## Because staying in one place is bad for your health.
In this environment, there are several species of life (can be plants, can be animals, can be fungi) that obtain food by trapping animals that wander through their nesting grounds, acting as a sort of living quicksand. They aren't very fast to react though, so if you just wander through, they can't do much. But if you decide to stay and camp, they'll congregate upon your location, and try to immobilize you. Try to sleep in such a place, and you'll wake up completely immobilized and being slowly eaten alive. And these things are so widespread and can camouflage their nests good enough that the best strategy is to just keep moving rather than trying to see if the spot of land is safe for rest or no.
[Answer]
## Mapping Behavior:
Your species never ***really*** sleeps in a conventional sense. They are constantly mapping out their environment, analyzing tracks and either predators or prey animals. They get to know even individual prey animals or predators. This deep understanding of their environments and prey mean that when they DO eat or hunt, they always know where and when to get a meal as easily as possible without worrying about being eaten in turn. The would know which watering holes dried up when. Constantly moving through their environment might also aid in spreading their scent everywhere, so predators and prey have a harder time locating them.
So really it's a difference between spending a lot of energy up front to learn all about their predators, prey and environment, or spending more time and energy hunting, stalking, chasing, and killing OR constantly fearing attack. If they are predators, they would have two choices. They could be ambush predators, and this would be the one time they would need to stop (but not for long, because they would already know when the prey were coming). This would minimize energy expenditure. Alternatively, they could be endurance hunters, following their prey until the prey was completely exhausted. Omnivores could forage WHILE hunting due to their great knowledge of the terrain. If they were herbivores, they would always know where the highest-energy food items were in season and have abundant calories.
A key component to this would be an extremely good memory. Your animal would need to keep track of all this information. This would also help with variations that didn't only involve terrain (like seasonal changes). I would also suggest they would be endurance animals, since keeping up all that motion would mean they would by default need great endurance (meshing well with the endurance hunter model).
* As an alternative answer, your animal may constantly deplete its food supply. It eats a small animal like mice and doesn't get much from them (being so big lets it uproot nests, but then it has to allow the population to recover). Or maybe there is a food item that takes a long time to mature but doesn't have a season (so the animal is always moving to the next tree/bush). If it is a herbivore, this constantly roving behavior may be used to carry seeds and/or pollen by its chosen plant. The plant could have a food pod/giant high calorie nut that only this animal can successfully open or eat (due to thick shells and/or poisons). Again, endurance and good memory help in these scenarios as well, to remember where nests and/or food trees are, and aid in constantly moving to the next one.
[Answer]
**Never Ending Buffalo Migrations**
On this world, there is a continuous band of land around the equator. A plain 1,000 miles wide where buffalo-like creatures routinely migrate in vast herds, circling the planet.
It takes a herd (travelling 30mph and resting only to graze and drink for a few hours a day) a little under four years to complete their circumnavigation of the world. They run through the night and day. But once in a while they will stop and eat, rest and drink for a few meagre hours before their instincts drive them on again.
Your Big Cat must keep pace with a herd, because there aren't so many herds it can't afford to sit and wait for the next one. Consequently, it has evolved to be able to run and track its prey in its sleep, because if it ever loses the herd it will be forced to go without food until the next herd comes along.
[Answer]
There is an excellent book "Player of Games" by Iain M. Banks, where the story moves to a planet with a perpetual wildfire, working its way around the world burning everything before it, but allowing fresh seeds and reinvigorated growth behind it.
The animals on that planet were always migrating to stay ahead of the fire. Although it has been used before, I think there is more scope to explore such a world.
[Answer]
This depends a great deal on the environment, and the question you really ought to be asking is "how would such a creature compete with similarly sized animals that don't have to walk all the time?"
Some of the answers here suggest a sort of biological weakness that forces the animal to keep walking. Such things exist on earth; Sharks are a great example. However, sharks use extremely little energy to swim, while a walking animal may be forced to spend a great amount of energy covering difficult terrain.
The only reason a creature like this would not be out-competed by more conventional animals is if:
1. There are no normal animals. All the animals in this world are forced to walk forever. This has huge implications for worldbuilding and animal behaviors; it may not be possible for animals to live in steep mountains or treetop canopies. This sort of thing might exist on a planet that turns very slowly, resulting in an extremely long day/night cycle. If the planet is a reasonably distance from the star, the night side of the planet may be too cold for animals to live through normally. Some animals will perpetually walk to stay in the sun (hopefully, they don't have to cross any oceans to do so), while others might go into a deep hibernation, probably buried extremely deep underground.
2. Walking forever grants the animal access to some resource that other animals can't get. Perhaps there are floating magic orbs that never stop moving, and, by following them, the animal in question can essentially eat the magic which this orb radiates off? In this case, the animal can't stop because it would starve, as it has become unable to live off of conventional vegetation.
[Answer]
Just to help, decrease gravity, increase air pressure. Not necessarily by much. Then it would consume less energy to move slowly. As your creature is very large, it has a large surface area and it will take more effort if it only moves when it is awake. And if the food is scattered, like large trees or bushes but no grass, then it is best to move to next place while (half) asleep.
Then you can add the other suggestions too. Since it constantly moves, looses its lungs. It makes sense, it is an extra organ. You can even normalize the environment some more, after the evolution took place.
[Answer]
## The planet is too close to its star, and if you stop you will fall into the hellish day zone
Life on this planet evolved when it was in a Goldilocks Zone, but due to interference from other bodies it has gotten closer to the star over the millions of years - Slow enough to give life time to adapt.
The day side of the planet is too hot for these creatures to survive, because instead of evolving to withstand the high temperatures, they evolved to stay ahead of them. Plants (and most other living organisms) have evolved mechanisms to survive these temperatures.
Now, these creatures constantly move so that they stay in the Night at all times - They have evolved to move all the time.
Perhaps these creatures, in a cruel twist of irony, photosynthesize (maybe they have symbiotic plants on their backs). In that case they'll have to remain in Dawn o Twilight at all times: Light so they can photosynthesize, not Day enough to be too hot.
[Answer]
Getting mineral from a known location <https://en.wikipedia.org/wiki/Mineral_lick>. [Roadkill](https://en.wikipedia.org/wiki/Roadkill#Road_salt_accumulations) is also fairly often happens because of licking salt on the other side of the highway.
[Answer]
It has some kind of superpowers of speed or agility like some mutant mitochondria equivalent cellular symbiont inclusions, but the same mutation causes it to lose temperature at whatever rate you say, which makes it catch colds or disease... Or its cellular symbiont requires a very specific temperature of 41 or it litteraly jumps into the blood stream looking for a warmer place, which gives it a sixth sense like vibration sense of every movement for 100m around in 360 degrees, and then the animal loses it's magic power for a few days until it manages to re-include the symbiont into enough cells to have the superpower fully running again.
[Answer]
The animal does not need rest. In fact, as soon as it stops moving, the muscles begin to atrophy and the cells begin to degenerate. Everything it its body is rapidly generates new cells with movement. All cells are short-lived.
[Answer]
This could be a sort of vestigial behavior, a trait that evolved to deal with some ancient factor that is no longer present, but that does not actively hinder their survival.
There's good evidence that humans used to be pursuit predators, simply tracking animals over long ranges at walking speed until the animals die of exhaustion. This "always walking" trait could be the result of dealing with pursuit based predation; eating/drinking/sleeping, but always moving. If such predators are no longer present the behavior would seem odd, but as long as the creature can still grab leaves and drink rain or dew off leaves; they'll live on, still moving for some reason that no one in modern times can quite figure out.
[Answer]
**Large Intertidal Biome on a Habitable Moon**
In theory, the tides on a Gas Giant moon could get dozens or even hundreds of feet higher than on Earth. Depending on the geography of a particular area, that could lead to the sea coming miles inland at high tide. Some US states are low enough to be largely flooded in such a circumstance, for perspective. Depending on how long the orbit of the moon in question is, these tidal floods could come on fast enough to mandate that any creature that can't swim can't just stay still for hours at a time.
Now sure, many animals in such a biome probably would have some swimming ability, but just imagine the rip tide on such a place. Any animal even remotely bound to the land probably wants to avoid getting in the ocean. Plus, during low tide, there are bound to be plenty of sea creatures and plants left out for eating before the tide turns again. Sounds like a decent niche to occupy.
[Answer]
There was a titanic creature called 'Marschiere-Viel' ('walk-much') in the german SciFi magazine 'Perry Rhodan'. It was living from the sunlight, so it needed to keep on marching to catch up with the sun.
[Answer]
**Your world has an ether, and living beings are sensitive to it.**
Creatures on your world are sensitive to a pervasive ether, which has variations (densities, polarizations, etc.) and either the ether moves, or your animal(s) have to move relative to it to do something (sense it, gather energy from it, etc.).
The ether could be a source of energy, either in place of or as a supplement to what we think of as normal sources, and different animals (and plants) can have different schemes for gathering it (e.g. plants are large enough to usually span the moving polarity regions, so they can always experience enough of a differential across their branches to acquire energy; floating oceanic life forms are naturally swept through the ether by wave action - so in calm seas they have to do more work, whereas in storms they're highly charged; some small animals find it more efficient to sway on flexible plants than run around; your animal is mid-sized so constant ambulation is cheapest while providing other benefits).
Your animal could also be sensing eddie currents in the ether, or creating eddie currents for signaling, and this requires movement. This could be done at the same time as or separately from the sleep-walking behavior, and it could be for different reasons (finding mates; remaining in contact with other members of same species; driving prey which live primarily in the ether but can "pop out" into the normal environment at certain junctures where your animal can consume them) and it could come with costs (there are other, larger ether-aware predators out there, and what your animal does to gain vision in the ether exposes it to being seen by things that would prey on it, just like light signaling in the ocean). A variation of Darth Biomech's answer also fits here: ether-aware predators might more easily recognize animals which stay in one place, and constantly moving could be a camouflage.
] |
[Question]
[
A fantasy staple, the [fantastic mount](https://tvtropes.org/pmwiki/pmwiki.php/Main/HorseOfADifferentColor) (TvTropes). People in Fantasy Land ride giant yellow chickens, giant wolves, giant beetles, caterpilars, ants, and other insects, [evolved bears](https://worldbuilding.stackexchange.com/q/38502/353), sharks, miniature dragons, wyverns, pterodactyls, and a plethora of other creatures.
But the horse, the ordinary, commonplace, *[Equus ferus caballus](https://en.wikipedia.org/wiki/Horse)* remains present. Why do people still use horses when there's so many other choices?
[Answer]
## Fantastic mounts have fantastic drawbacks
* **giant yellow chickens**: incessant deafening clucking, razor-sharp beak is lightning fast; uncomfortable to ride
* **giant wolves & evolved bears**: way too dangerous (neither animal is domesticated); if "evolved" means "smarter," then too hard to control
* **giant beetles, caterpillars, ants, and other insects**: absolutely terrifying to everybody who is not an entomophile; ants, at least, respond to invisible scent trails; all these bugs are especially difficult to corral because they can climb walls; uncomfortable to ride
* **sharks**: not usable on land, and humans can't breathe underwater; also, most humans prefer to *not* be submerged in saltwater every time they travel somewhere; only practical for people who live on the shore and whose travels are exclusively to other shore-adjacent locations
* **miniature dragons**: way too dangerous (dragons are not domesticated, and breathe fire, *and* are often regarded as having intelligence on par with humans which makes it extremely difficult to enslave them)
* **wyverns**: way too dangerous (wyverns are not domesticated, often have magical attacks like breath weapons, and have reptile cunning)
* **pterodactyls**: incessant deafening screeching; some people are afraid of heights; like the giant chicken, surprisingly difficult to saddle
I know that video games make it appear that the only difference between a horse, a dragon, and a giant spider is cosmetic, but this is a fatally simplistic perspective. These creatures are very different from each other, and when you make them bigger you also make their drawbacks bigger.
Also, every one of these creatures will produce a lot of gross waste. If you think a pile of horse dung is nasty, just wait until you see the revolting slurry that sprays out of a pterodactyl.
Horses are safe. Horses are good. Horses do not silently kidnap neighborhood children, wrap them in silk, suspend them from the roof of the barn, and let hundreds of little horses literally suck their liquefied organs out for nourishment.
[Answer]
# Horses are safer.
A reasonably well trained horse (not the "groom killer" type that some macho riders have sometimes preferred due to a delusion that they're stronger or faster than a well-disposed steed) is loyal enough to make a good dog look like a fly-by-night, will uncomplainingly let a human ride it to death, is about as smart as a dog (maybe smarter, depending on individual variation) -- and ***far*** easier to stable, train, and care for then a giant yellow chicken, dire wolf, etc.
# Horses are common
Horses are likely cheaper to feed than most fantasy mounts, as well. Although a horse needs oats (or other grain) to give maximum riding performance, when not being ridden regularly horses can live pretty well on less expensive hay or (nearly) free open grazing. Horses have been bred on a routine basis for centuries, while these special mounts are presumably relatively new to the task (else they wouldn't be "special"), and the skills to breed, care for, and train them, as well as to make and use their accessories (saddle, harness, tack, etc.) are common, rather than exotic.
[Answer]
# A Horse is Less Expensive
**Fantasy Mount**
1. Getting one isn't easy, or cheap
2. Taming and training takes time and money
3. It has uncommon dietary needs
4. They require custom hardware (saddle, bridle, straps, etc.)
5. They need specialized stables to house them when your not out riding.
**Horse**
1. They can be bought from a breeder or trainer
2. They are easily trained, and standardized training methods exist, so someone else can do it for you.
3. They graze just fine, and are cheap to feed when grazing isn't an option.
4. You can have a single saddle for your life and move it from horse to horse and it should fit just fine.
5. Everywhere has stables to board your horse.
[Answer]
Not everyone drives a dragster. To buy bread a beaten up Honda Civic is more than enough.
Same for your mounts. Why messing with a monster when a horse is quieter, safer and better manageable.
[Answer]
# Magical animals require magical food.
Magic is very intensive on the body. It requires a lot of fuel to make whatever unnatural body plan work. As such, you need magical food. This food is generally quite expensive and intensive to grow.
Horses eat normal food. As such, they are the reliable choice if you can't source whatever fancy exotic stuff your magical mount needs.
[Answer]
## Humans can bond with horses
I'm going with a more *emotional* approach that can be the basis of logical reasons. Humans can have a special bond with horses and it can lead to a lifetime companionship. The relationship is marked by mutual trust, respect and affection in which humans and horses would see each other as family. Horses are emotional and social animals and they can suffer from loneliness just like us. Even in the wild, horses are pack animals that tend to stick together and have a family structure. This bonding would be the main reason why everything else would work out well.
Humans can't bond with other mountable fantastic beasts like horses and they are not as tameable as horses. With horses, people can also form a cavalry per the pack structure and bonding; where there is strength in numbers.
[](https://i.stack.imgur.com/KQXEzl.jpg)
*Image scource: wallpaperflare.com*
[Answer]
**Would you take a tank, a tractor, or a helicopter to go to McDonald's?**
No?
The same applies here. Giant tigers are awesome for fighting. Rhinos are epic landmowers. Dragons fly you anywhere in no time. But if you're just going to your daily office work, you just need a mount that's fast, reliable, and small enough, without need for special care.
Horses are perfect for this. They won't eat John, the hostler. They won't rampage away randomly, demolishing the pens and then everything in their general direction. They won't burn down the office when they sneeze. They just munch away calmly.
Just as in our life you ron't take a dragster or a Cenessa to go to work, you won't need special magical animals for your daily commute. Every animal breed will have its place in this world, and horses will be your regular Honda Civics.
[Answer]
I blame the labor unions.
The union representing pegasi has won time schedules that keep pegasus operators from using them as regular mounts. 8 hours of rest after one hour of flight time. Only divine beings (and their representatives) can afford the stabling requirements necessary to meet work-rest hour requirements.
Dragons United demands a wage scale that frankly explains *why* dragons end up perched on massive hoards of gold. Hiring dragonslayers to eliminate dragons willing to work at below-guild scale helps to keep dragon mounts as something only the wealthiest (and soon to be former) billionaires can afford for now.
The demand by unicorns that their riders be (1) female and (2) either human or elven is currently under litigation in multiple jurisdictions for violating civil rights laws. Spokescreatures for unicorn societies have stated that they will quit the business totally if those requirements are overturned. Spokesorcs for *Orcs Are People Two!* have promised to continue to fight to overturn such restrictions as they are speciest as well as sexist.
Nightmares Unlimited™ is still committed to overturning health and safety regulations banning flaming body parts during the drought. They also claim that reports of luring young people onto their backs and hauling them off to Hell are fake news.
[Answer]
Probably for the same reason horses were chosen in the real world: Of the animals that *can* be domesticated, horses arguably make the best mounts. There are something like 150 real-world species of large land animals, and of these, only about a dozen can be domesticated. The rest might be captured and trained, or possibly raised from infancy and bonded with, but they can't be produced in quantity or bred for specific purposes.
Again in the real world, there are basically six traits that a species has to have to make it possible to domesticate. This is mostly summarized from Germs, Guns, and Steel:
1. Diet - you have to be able to feed it. Large carnivores generally fail this test pretty hard. 100 tons of grain will feed 10 tons of herbivores or omnivores, but those will in turn only feed 1 ton of carnivore. Horses can eat grass.
2. Growth Rate - If an animal takes 15 years to reach maturity instead of one, it's going to be cost-prohibitive in most cases. That's why we don't have Ape-ranchers.
3. Captive breeding - can't do selective breeding if you can't select who it breeds with. Some species just won't breed in captivity. Some need elaborate mating rituals or they won't conceive (ex: cheetahs). Some have complicated territorial requirements (ex: vicunas).
4. Personality - The animal has to have a disposition you can live with. Hippos will try to kill you just to see if they can. Grizzlies are prone to violent rages when frustrated, and psycho-girlfriend levels of jealousy. Zebras are irascible SOB's, especially as they get older - they'll bite you and drag you around a bit if they don't like something they imagine you did.
5. Calmness - they can't be too prone to panic. Gazelles have never been successfully domesticated because they will bolt blindly at the first sign of strangeness and either leap over their enclosure wall or bash themselves senseless against it.
6. Social Structure - There has to be some kind of social structure that a handler can take advantage of. All large domesticated animals have five features in common: a) they live in groups, b) they maintain well developed dominance hierarchies within their groups, c) those hierarchies remain fixed once established, d) they can imprint on the creatures around them while young and accept a human handler as part of the group, and e) they have overlapping home ranges rather than exclusive territories.
7. Suitable as Mount - On top of all that, if you want them domesticated specifically as *mounts* then they have to be capable of resting while standing, traveling long distances, carrying sufficient loads, moving fast, etc.
To make room for horses, you just have to select one of the domestication criteria that each of the fantasy mounts fail - or at least compares unfavorably to horses. Giant chickens might fail for the same reason as ostriches (bad basic skeletal structure for long distance load bearing), giant wolves might bond too closely with their handlers to ever raise for sale, etc.
The fantasy mounts will still be used if they exist - giant chicken races could be a thing people bet on, giant ants might be used for mining, and every military will want flying scouts regardless of the price. They will all be breathtakingly expensive of course; your typical farmer won't have one. But even nobles who can afford whatever they want will likely pick a horse over a giant beetle. Kind of like why you would choose to drive a car instead of a backhoe on your daily commute.
[Answer]
The benefits of the horse over fancy beasties fall into three main areas: it's easier to get, easier to maintain, and more broadly useful, even in a world where other options are common enough that they won't run into issues on that basis alone. While individual adventurers or heroes with unique use cases might ride a fantasy creature, everyone who is not a one-man army will find that the horse is the ideal, well, workhorse of a mount.
## Acquiring your mount
You can't just go to the mount store and buy a mount if you're in caveman times and stores haven't been invented yet. Capturing, taming, domesticating, and breeding animals is a sophisticated technology, and societies figure out how to do it for the horse long before they do it for anything else. So by the time society starts to domesticate something else as a mount, the horse is already in common usage.
After horses have been invented, they are easy to produce: their gestation period is relatively short and they grow up quickly. This is important because while a horse is still an investment, they are easy to find and to convince the current owner to part with.
## Keeping your mount
You can stable a horse, and it will stay stabled, not fly away or decide to do something more interesting. As herbivores, they are easy to feed - critical for an army on the move. Horses are comfortable in broadly the same set of conditions that we are. They do not insist on being entertained, and will not mind if the rider tells bad jokes. In the cold, a horse is warm.
## Using your mount
Horses are herd animals that are well-behaved in large groups (like an army). Horses are about the right size for a human to jump into the saddle quickly, and not to get hurt too much when they fall off. Horses are comfortable moving at a pace that humans find useful - neither crawling slowly nor shooting forward so quickly that they outpace the rest of the army. Horses can walk for as long as humans can. Finally, horses are *heavy* - in a cavalry charge, the horse's significant weight is transferred into the blow of the weapon in a way that a giant chicken simply couldn't match.
A horse is not just for riding. Horses will pull a plough or a cart. They are large enough to carry multiple riders. A horse's flank will shield you from sight or low-velocity projectiles. As a last resort, a horse is edible, and its remaining tissues are valuable for various crafts.
[Answer]
# Magic leaks
Depending on how magic works in your world, it may not be a good idea to be near strongly magical beings. You could be creating a world in which mana poisoning is a thing - throwing someone weak into an area of intense ambient magic would kill them due to their bodies being unable to handle it.
In a world like that, having a safe, mundane mount would be important for people who are not adventurers that have trained their bodies to be able to handle the intense magic coming off of strongly magical creatures.
[Answer]
Besides all of the reasons stated in the other answers, never understimate the power of personal preference and aesthetics:
>
> "The supple muscles under the silky coat, the music of the hooves...
> the velvet of the muzzle, and the inscrutable black sea of their eyes.
> Ah, the horse!"
>
>
> *Lord Haurchefant Greystone of House Fortemps*
>
>
>
[Answer]
## Training
Some animals are much easier to train than others, and are capable of forming a bond with their trainer or owner.
Not so very long ago, there was a guy with a [Pet Hippo - that ended up killing him](https://www.theguardian.com/world/2011/nov/14/pet-hippo-humphrey-kills-owner)
5 years in, after being together for a long time, the hippo still killed him.
This is not an unusual sort of story - there's actually quite a short list of animals that are really capable of forming the kind of bond with a human that's *necessary* for them to be an effective and safe animal companion.
Additionally consider wolves vs. dogs. They're superficially pretty similar, but a significant shortage of pet wolves. Why? Their temperament, social dynamics, and acceptance of humans just isn't there in the same way. A *few* 'tame' wolves exist, but most of them remain pretty wild and prone to letting instinct take over.
<https://en.wikipedia.org/wiki/Wolves_as_pets_and_working_animals>
They're simply so much harder to work with, especially if you're looking to achieve functional domestication (e.g. able and willing to work with most humans, rather than just the one you know).
There's a reason there's never been any hippo cavalry regiments, despite how they'd be pretty amazing 'warhorses'.
[Answer]
# Familiarity
Everyone is focusing on in-world reasons for horses being so common in fantasy settings, but can we take a minute to think outside the world? Having horses in a fantasy setting gives the audience a connection to the world. I know what horses are, you know what horses are, we've probably seen real horses in our real life. Not sure if I have seen any flying dragons or a person riding a shark in real life.
Commonality between your setting and real life gives the reader a grounding point to truly become immersed. Horses make a pretty good way of having reliable transport, especially when most fantasy settings, when looking at real world history, chronologically appear medieval. A setting that resists any connection to reality will likely be difficult for the audience to immerse themselves in.
] |
[Question]
[
**Closed.** This question is [off-topic](/help/closed-questions). It is not currently accepting answers.
---
You are asking questions about a story set in a world instead of about building a world. For more information, see [Why is my question "Too Story Based" and how do I get it opened?](https://worldbuilding.meta.stackexchange.com/q/3300/49).
Closed 5 years ago.
[Improve this question](/posts/110316/edit)
You are a normie on 2019 Earth and suddenly you can't find anybody. You've searched for a few hours, tried spamming out emails, random phone calls - no response. What would be the most jarring evidence that everyone in the world has disappeared?
You would be looking for assurance that you are alone, I imagine. By "most" I will settle for the largest number of people by some proxy like land area.
I imagine things like:
1) Within a few days it would be "dog eat dog" as wandering pets try to adjust to lack of pet food.
2) Within a week it would be "Lord of the Flies" as insects make food stores impossible to enter.
3) Within a few weeks it would be "trial by fire" as the stores of flammable material eventually ignite.
But I'm struggling to build the world of the first few hours, the first few months, the first few years, etc.
[Answer]
Go to [StackOverflow](https://stackoverflow.com) and see if a question was posted in the last minute.
[Answer]
**Turn on the news.**
This may seem obvious when what you want is to get informed about the world, but it should work fine for this. Most of the biggest news channels-- CNN, Fox, MSNBC-- have 24-hr news cycles, meaning somebody is always on the air discussing something. Allowing for commercial breaks, you should see someone doing a live broadcast within a few minutes.
If nobody comes on, this doesn't necessarily mean you're the only person left alive, but it does mean there are an *awful* lot of people dead or gone.
[Answer]
**Listen to the radio and wait for the power to go out.**
Checking satellite orbits isn't a feasible way to check for other humans. Such things are done autonomously and even if not, the process would require special access to the exact place where the adjustment would be done or special equipment to determine any deviations. And, if you are indeed a "normie" in 2018, you're not going to know anything about how to identify a satellite let alone track its orbit with any precision.
[Power plants will shut down within hours or days](https://worldbuilding.stackexchange.com/q/41587/3202) without human intervention though. So waiting for the power to go out will be a good sign that at least the people responsible for that job are now gone.
Alternatively, just listen for radio broadcasts. Significantly more people in the world have access to radio transmission equipment than access to satellites or power plants. If no one is broadcasting on any frequencies, then you'll have a much better evidence for there being no one else left in the world.
Finally, if the power really is staying on and the internet is still active. Just check Reddit (or some other heavily used site) and sort by new posts. If other people are out there, they'll post something online, just as you might be doing.
[Answer]
Assuming you still had a working internet connection and a steady power supply, you could get a view of the globe by watching a live feed from the ISS and comparing it to a previously recorded video. If everyone had indeed disappeared (and not just the people close to you), you should should be able to observe a lack of light pollution in the areas where cities used to be.
[Answer]
Bizarrely enough, Tinder may be the solution for your problem.
Some social networks such as Facebook and G+ (or whatever Alphabet is up to now) have features to find people near you, but the distance in which they search is usually fixed, non-disclosed, and doesn't go beyond a city. Tinder on the other hand allows you to hook up with strangers in another continent if you set your forever alone radius search radius large enough.
Don't forget to match everybody you see. Also keep in mind that:
* The fact that they are matcheable does not mean they are online.
* The more matches you make, the more chances you have to contact someone.
Since this seems like a life or death situation, you might set your preferences for both men and women to increase chance of contact. Then hope that you are not just having a bad trip from spoiled acid and have to explain stuff to your spouse when you're sober again.
You may also try some popular sites where anyone can post. Just remember, if the site has "chan" in its name, then whatever answers you is probably not human.
As for satellites, all a new orbit would tell you is that a satellite has been moved, but unless you work as a satellite operator that does not tell you why, when, nor how. Skip that.
[Answer]
### Use both the oldest and newest technologies at the same time:
I hate to say it, but FaceBook is the busiest site on the planet, so just fire off friends requests to all of the friends of your friends...
The phone: don't call randomly, but go by address: As web sites are still up, go to your country's equivalent of whitepages.com, start looking in your own zip code, and your own street, go to the streets around you and widen your search geographically the less response you get.
In no time you'll know whether 90% (1 in 10 responds) 99% (1 in 100), 99.9%, ... has disappeared. A couple of days of searching would mean 99.95% has disappeared.
[Answer]
**Light a Large Fire**
Inspired by the [Eruption of Mount Edgecumbe](http://hoaxes.org/af_database/permalink/the_eruption_of_mount_edgecumbe/) prank.
Head to the nearest junkyard and light a pile of tires on fire. Tires make thick black smoke that can be seen for miles.
Lighting a big smelly fire that can be seen for miles would alert anyone left around. A [smoke signal](https://en.wikipedia.org/wiki/Smoke_signal) is a time honored and ancient way of getting people's attention at a distance.
[Answer]
You can't tell not by any means quickly. Most of the world doesn't have unrestricted internet access. Most of the world is very poor. If nearly everyone in China and North Korea and other restrictive countries had disappeared, it would take a long to find out. It would take a long time to find out about disappearance of the poor people in less restrictive countries. All the other answers are about tiny percentages of the world's population disappearing.
[Answer]
Call a major technology company's Tech Support. If nobody replies, or there's almost no hold music, you're in trouble.
[Answer]
You could do like "The Last Man On Earth" TV show with Will Forte, drive around, leave messages on billboards, finally settle down and see if anybody finds you.
"In 2022, a cataclysm strikes Earth, seemingly wiping out the population save for former family man and bank employee Phil Miller. Sad and very lonely, Phil travels the United States, Canada and Mexico in his RV searching for other survivors. Striving to hold onto hope that there is at least one other living person, he tries to make the best of circumstances until his path finally crosses with that hoped-for other survivor -- and all becomes more comforting that the person happens to be a woman. As more survivors turn up, complications arise and Phil finds it difficult to co-exist with others again."
] |
[Question]
[
A very common trope in witchcraft-themed fictional narratives is the iconic Magic Broom, a magical object made from wood and straw to fly and serve as a vehicle for witches. Witches generally fly with the broom between their legs, although sometimes women fly sitting sideways with both legs together (some men do too, but so far I've seen more women riding the broom like this, like riding a horse in sidesaddle form). That said, I ask: **What would it be like to ride a broom?** Because the broom stays in the air (except when it goes up), but your body, according to the laws of physics, tends to go down. It's like sitting on the handrail of a ladder with your legs spread and the handrail between them. It shouldn't be very comfortable, especially for a man.
Note: with no answers involving magic used on the witch or person who will ride the broom, the **only** magic allowed is the one that makes the broom fly and does not break under the weight of a human being on it. Also no saddles or anything that makes the broom more motorcycle-like, the point is a broom that is true to its broom design. My question is whether it would be comfortable, whether it would hurt, etc... Not about how riding a broom.
[Answer]
### Perfectly comfortable, since witches weigh very little
It's widely known that [witches weigh as much as ducks](https://youtu.be/zrzMhU_4m-g?t=164). And ducks are already very light creatures, to allow flight, with adults weighing [up to 3.5 kg](https://www.researchgate.net/figure/Average-body-weight-kg-of-14-21-and-32-day-old-ducks-by-gait-score-There-was-an_fig1_274092901).
The discomfort from riding a broom is due to the pressure of an adult's weight over the few square centimeters of area the person is sitting on. A witch is at least 15 times lighter than normal humans, and therefore can sit on a broom with no discomfort, even when carrying additional accessories, pouches, and a familiar.
This is also why they have to tightly hold the broom while flying, otherwise they'll be blown away by the wind.
[Answer]
**Like riding a skateboard.**
Most witches ride a broom with one foot in front of the other, standing atop the broom. Young witches often go barefoot and might hold their arms out to the side for balance. Occasional witches ride with feet at right angles to the stick, and look sideways over their shoulders.
Old witches nod and smile, and stand on their brooms wearing their clunky shoes, arms folded in front or behind them.
Images drawn of witches sitting on brooms are drawn by ignant people. Sure you could do that, but it would be uncomfortable.
[Answer]
Witches don't actually ride on the broom as your would ride you stick-horse or motorbike, their weight is not exerting any pressure on the broom.
They use the broom:
1. as a conduit for the magic power that allows them to fly
2. as a way to control their flight course and manage the acceleration while in air
Even a rotten heirloom broom stick with barely any mechanical strength, passed down the generations, from the witch-mother to their witch-daughter, is good. It's even better than a newer one, since the magic veins (allowing the magic to flow) of the old ones are already formed and fined tuned for the purpose.
[Answer]
Slide back until you're seated comfortably on the cushion of bristles.
I just experimented with a broom in my garage, and, by sitting on the upper end of the bristles, was able to balance easily on a rail.
[](https://i.stack.imgur.com/R6jNz.jpg)
[Answer]
*in an old crone's cackling voice*
Comfort? This is magic, the absolute subjugation of physical laws by indominable will power. It is technically impossible, yet it happens because the caster demands it to. It is pure misery to push a human mind that hard, yet you're troubled about having to rest your delicate parts on a hard wooden staff. I bet you brew your curses in an aluminum caldron because cast iron is too heavy and tough to clean.
I'm seriously worried about this next generation of witches and warlocks we're raising. They are too soft to survive.
Okay, let's get back to the basics...
Every spell requires a power source. Not surprisingly, the ecstatic sensation of flying draws from the ultimate ecstatic realm of the erotic. Hard wood between legs... it's pretty obvious symbolism. If it hurts a little while getting airborne, that only contributes to the metaphor. Once things get off the ground, there's plenty to distract you from any minor discomfort. The broom and its rider, soaring ever higher to reach new heights.
So in answer to your question, yes, brooms are uncomfortable... but it won't bother you near as much as you fear it will, once you get used to it.
[Answer]
## Hanging upside down, screaming for help.
Most witches know about the *other* magic required for a broomstick besides just flying, the magic that gives you some invisible seat, but occasionally a young witch is self-taught for some reason and tries to use a broomstick flying spell without any extra spells. She inevitably ends up hanging upside down from the broomstick, screaming for help.
Broomsticks are narrow and round. The roundness means there's nothing to stop them from rotating (or, more precisely, you from rotating around the broomstick) except for friction. The narrowness means that there isn't that much friction available. The center of mass of a human is generally somewhere above what you sit on a broomstick with. If you're very careful and don't make any sudden movements it's possible (just barely) to keep your balance by keeping your center of mass directly above the broomstick. But the first solid gust of wind that comes along, gravity will take over, your center of mass will go downward, and you just spin around the broomstick until you're hanging upside down, holding on for dear life, hoping there is someone nearby who can get you a ladder. (You could try to land upside down, but really since you never fly without the seat spells *twice* the people who find themselves in this predicament aren't exactly skilled fliers who can navigate under upside down circumstances.)
[Answer]
**Two Legs on Same Side.**
This is the more comfortable and common way to ride the broom. The misconception that witches ride with one leg on either side (straddling) is because (a) they do this on takeoff and landing for extra stability and this is when they are most visible and (b) It is sexually suggestive and sex sells.
[Answer]
There is a technique for crawling along a narrow pole or rope - you lie down flat and hang one leg down. That lowers your centre of gravity below the rope, making you stable.
[](https://i.stack.imgur.com/DTe1l.jpg)
If there's no magic in use other than that making the broom fly, this technique would allow you to stay on top of the broom, and spread your weight enough that's not painful. It's fairly aerodynamic too!
[Answer]
---
## **Just attach a bicycle seat to the broom.**
---
Bicycles have a similar build to a broom; most of their mass is made of thin tubes. A bicycle seat, while not necessarily comfortable, is much better than riding on the bare tube itself.
Also, you could attach stirrups to the broom as well, to hold the rider's feet in place, and possibly even increase the rider's control of the broom.
[Answer]
It is a common misconception that the broom is providing lift. Witches fly by casting spells. However, to sustain flight, they need a focus object, so their spell doesn't fizzle out, crashing the witch to the ground. Brooms just happen to be the best focus object for the flight spell.
Since it's the witches providing the lift, there is hardly any pressure between the broom and the spot between the legs of a witch.
Young Californian witches are sometimes spotted to ride their brooms while standing on them.
[Answer]
Like 0G.
The witch's weight does not rest on the broom. It is the witch that holds the broom's weight.
The broom is just an instrument that helps the mind focus its magic, akin to the wand of a fairy godmother or the staff of a mage. Where she points the broom she goes. The more experienced crones are able to fly using other paraphernalia, without the need for something pointy - Baba Yaga is famous for flying in a mortar, and I remember something about Nanny Ogg flying naked in a bathtub.
[Answer]
## It would be very painful...
Sitting atop a narrow wooden bar while experiencing the g-forces of flight... **ouch**! Other than that, if you've ever sat on a bar before, you'll know the only thing keeping you from swinging sideways is your ability to grip the bar. You need to tightly grip it either with your hands or thighs to prevent yourself from rolling sideways. It will be tiring to both your legs and hands, even more than horseback riding, since the thing you're griping is a narrow wooden bar.
Speaking of rolling sideways, there needs to be some magical force preventing the broom from spinning or riding the broom will be like log-rolling down a river. Without any second force preventing the broom from rotating, there is no chance for the witch to stay atop the broom, the slightest imbalance will cause the witches center of gravity to skew off center, which will immediately tip them over. Flying upside-down is also very painful, the blood rushing to your head will cause head-aches and even make you pass out after a few minutes.
[Answer]
Some bicycle saddles are very narrow and unpadded.
To be fair they are only comfortable (somewhat) because most of the rider’s weight is borne by the legs and arms.
Still, sitting on a stick of similar diameter would be entirely possible without damaging your genitalia.
For added comfort you’d shape it, add stirrups, add arm-rests etc.
[](https://i.stack.imgur.com/ST60o.png)
[](https://i.stack.imgur.com/rOggt.jpg)
[Answer]
Flying on a single broom is very uncomfortable... So they prefer to fly on top of a raft made of brooms
Nothing prevents a witch from using more than one broom to fly. So they could tie more brooms together to build a vehicle that is more balanced and comfortable to sit on
Of course, if a witch wants to ride a single broom, in order to have a better balance and avoid rolling, I think they would ride it with the back downside, with the legs crossed around the rod (like people crossing a river on a rope)
[Answer]
**It would not hurt**
It is indeed uncomfortable or painful, but only for a short while as witches travel very fast.
During the height of the witch trials of the 16th and 17th centuries, common belief held that a witch could be discovered by pricking their skin with needles as they would not feel the pain.
Therefore, the smaller pain from riding a broom would not be felt.
] |
[Question]
[
From what I know about the periodic table, in order to add a new element it would have to be above the current highest element. And up there this new element would be unstable.
But could I just replace an already existing element on the table, such as iron or a lesser known metal like vanadium? The new element would take on the atomic number of Vanadium. Is this possible?
This element (we'll call it Lerite) is going to act sort of like a magnet, but instead of magnetic force it's a different but similar force, allowing organisms to use telekinesis.
SO it'd be a great help to know what metal is uncommon in a earth like planet, but wouldn't be missed if it were replaced. Obviously Iron and gold is off the table. But more obscure elements which are useless to humans. Preferably it would be magnetic.
To simplify things, I don't want to *add* a new element as that would be impossible. I want to know if you could *replace* a current element on the table with a new one. SO: **Not add. Replace.**
---
Thanks to some ATOMIC answers I know now that replacing an element isn't possible: It's still iron if it's got the same amount of protons.
So to achieve my goal I'll just add a new force caused by a new subatomic particle that only a few suitable elements will use. Likely I'll be renaming these (if not all) elements on the table due to a different history. What fun.
[Answer]
Unfortunately no, you can't replace an element of the periodic table because the ordering of the elements on the periodic table are based on the number protons found in the nucleus of the atom. **However, you may have another option.**
Carbon has 6 protons, always. Give it an extra neutron? Still carbon. Give it an extra electron? Still carbon. Give it an extra proton? Now it's nitrogen. No getting around around it, any atom with 6 protons is defined as carbon, so you can't just replace spot number six with a different element.
However, that doesn't mean that all carbon acts the same. [Diamonds](https://www.google.com/imgres?imgurl=https://upload.wikimedia.org/wikipedia/commons/thumb/8/8f/Apollo_synthetic_diamond.jpg/220px-Apollo_synthetic_diamond.jpg&imgrefurl=https://en.wikipedia.org/wiki/Diamond&h=193&w=220&tbnid=t0Rz0lf337tN2M:&tbnh=175&tbnw=200&usg=__OCul4NzQGl-ghBQmcua16ZeHu4Q%3D&vet=10ahUKEwiOg5Th85TZAhWlxFkKHby4DfwQ_B0IwAEwDg..i&docid=PLwzjX3umP_rIM&itg=1&sa=X&ved=0ahUKEwiOg5Th85TZAhWlxFkKHby4DfwQ_B0IwAEwDg) are made of carbon. [Graphite](https://upload.wikimedia.org/wikipedia/commons/3/3d/Graphite-233436.jpg) is made of carbon. Why are they so different? Because of the atomic structures that carbon can stably form. [Allotropy](https://en.wikipedia.org/wiki/Allotropy) is the ability for some chemical elements(like carbon) to take multiple forms, and this can result in vastly different properties from the same base element.
So, while you can't scientifically replace an existing element with a new element, you certainly **can semi-scientifically say that some element has weird properties when structured a certain way**, and that simply nobody had tested that form yet in our world.
[Answer]
**Option 1: Island of Stability**
As @AlexP mentioned in a comment, there is a theory called the [Island of Stability](https://en.wikipedia.org/wiki/Island_of_stability), that states that there may be a window (or windows) in the super-heavy elements which are stable. The current expected window is in the 120s, but you could have another window; say the 180s or 230s (or whatever). The elements might occur extremely rarely in nature; say one or two atoms from the largest of supernovae. And once scientists in your world find it, they could replicate it.
**Option 2: Compound Rather than Atom**
You could make a compound rather than a single element. Since other answers have covered it, I will just point out that this is a fairly common sci-fi trope, like Promicin from *The 4400* (a neurotransmitter) or Midichlorians from *Star Wars* (a mitochondria like cellular symbiote)
**Option 3: An Alternate Subatomic Particle**
You could introduce a new particle to the nucleus. Let's call it teleron. A teleron has 20% more mass than a proton, and has one half charge of a proton, and also a telekinetic charge. So then you could have Telecarbon, which has four protons and four telerons. It is heavier than carbon, but has the same positive charge, so it can take the place of carbon in certain compounds. Enough Telecarbon (or Telerons in general) in a person's body, and they can manipulate the TK charge.
**Option 4: Just Pick One**
Instead of replacing an element, just pick one and use it.
**Option 5: One or More of the Above**
Use Telecarbon, but it is only useful in a certain compound. Or in a compound with rare element 333.
[Answer]
Given what you're trying to achieve, new elements aren't going to help you. I'm not an organic chemist, but what I do know about organic chemistry is that the effect you're trying to achieve is almost always solved with a *compound*, not an element.
Caffeine (C8H10N4O2); a carbo-hydro-nitrate (?) gives us a lift and makes us feel more energetic because it mimics a chemical in the brain that is generated when we're tired. The receptors for that chemical in the brain receive enough of that chemical, and it tells our brain 'we're tired'. We go to sleep, the chemical breaks down and our brain is no longer receiving the tired signal.
What Caffeine does is block the receptors, without triggering the response. As such, it actually blocks the real chemical from being received by the brain so it doesn't get the signal being generated chemically.
(This is all a simplification, but functionally correct)
The point being, that exotic elements aren't that common in drugs that affect the brain. Check out Alcohol (C2H6O), LSD (C20H25N3O), Cocaine (C17H21NO4), Methamphetamine (C10H15N), and even [Anti-depressants](https://en.wikipedia.org/wiki/Selective_serotonin_reuptake_inhibitor).
What do all of these seem to have in common? They're all Carbon, Hydrogen, Nitrogen and Oxygen combined in some permutation.
Ultimately, there's good reasons for this. These are the chemical elements that have been built into life for billions of years, and the sequencing of compounds allow for far more flexibility than a rare element.
I really think that your best bet for believability is that your secret element isn't on the Periodic Table, it's a CHNO compound that excites a specific part of the brain to over-activity, opening up a latent capability that humans would have naturally evolved in the next 500k years or so. It's certainly more scientifically more likely than a rare element combining with existing stable organic molecules to generate new classes of compounds to somehow augment a stable biological chemical code base.
But, that last statement is only personal opinion.
[Answer]
Shyassasain:
What might work for you is **allotropes**. That is, different crystalline structures for the same element. A famous example is graphite and diamond (both are pure carbon). *Very* different properties, exactly the same element. Here's the Wikipedia article on allotropy: <https://en.wikipedia.org/wiki/Allotropy>
Kirt Vonnegut' novel *Cat's Cradle* uses a fictitious allotrope of water, he dubbed **ice-nine**, as a plot device. Actually, **real water** has a whole bunch allotropes, including **11 kinds of ice**--depending on temperature and pressure, plus liquid, gas, and a weird phase at high temperature and pressure where there's no difference between liquid and gas. Here's a page about all the allotropes of water: <http://www1.lsbu.ac.uk/water/water_phase_diagram.html>
Another example of allotropy is **pure tin**. At room temperature it's the familiar shiny silver metal, but drop the temperature and the atoms rearrange themselves from octahedral to tetrahedral. The crystal swells up, becomes dark gray, brittle, and cracks apart. Check out this time-lapse video taken at -40°: <https://www.youtube.com/watch?v=sXB83Heh3_c> Note that the reshaping is reversible if you warm up your "tin pest," although you'll have little particles of the familiar silvery tin, not a big chunk.
**Pure Plutonium** is famous for it's extreme allotropy at room temperature, where it takes on **6 different crystalline forms**. Never mind the toxicity and radiation, the stuff is hell to work with because it keeps shifting forms when you monkey around with it (such as trying to cast it, press it, machine it, etc).
**So how might you use allotropy?**
**Pick an element** that has the required abundance. **1) Crank the pressure waaaaaay up** and raise the temperature too--your common element will rearrange itself into the perfect crystal form that's precisely what your story needs. **2) Hold the pressure** and drop your temperature into the cryogenic region--crystal is still stable. **3) Hold your temperature** and drop your pressure down to the normal normal region--still stable, but it'd never ever form under these conditions. **4) Raise your temperature** back up to the normal region. Perhaps your new "cobalt-nine" (or whatever you call it) is semi-stable when treated this way. Maybe it looks *nothing* like the metallic cobalt we all know and love. Maybe it's a pale blue transparent crystal. But smack it with a hammer or zap it with an electric spark and it reverts back to metallic cobalt (just to be different, it should shrink as it does so).
**Living things** often concentrate and crystallize elements (e.g. teeth) and sometimes even the more exotic--such as tiny spindle-shaped crystals of magnetite in the brain--a built-in compass. Suppose **some life form is able to create your "cobalt-nine" within it's brain,** assembling the weird crystal atom-by-atom, and therefore gains **telekinetic abilities** (or whatever your story needs).
Maybe smart people figure this out and through experimentation they create **synthetic "telkon" crystals and implant them into human brains**. They work, but are unstable (break down) or toxic. Maybe the final answer is a thin coating of titanium (biologically inert) a few dozen atoms thick (or better yet titanium-nitride), before the crystals are injected.
**Best of luck with your story.** And consider using allotropes because we know so very, very little about them. Therefore you can just make stuff up and it will sound plausible.
**These ideas freely given.**
[Answer]
Firstly, Lerite sounds like a mineral, not an element, so I think if you are going to invent an element you should give it a more appropriate name.
Some elements have more than one name (columbium is now called niobium for example) so it could be an existing element.
Dysprosium (element 66) has been mentioned in another answer, but I don't see it as particularly significant. All the Lanthanide series are quite rare, but Samarium (element 62) is used in powerful samarium cobalt magnets.
If you're looking for an element with weird properties, try [Technetium](https://en.wikipedia.org/wiki/Technetium), element 43. Despite its fairly low atomic number, it has no stable isotopes so it must always be prepared from other elements and is highly radioactive. Similar levels of instability aren't seen again until you get past Lead (element 82.) You could handwave a stable form of technetium, I suppose, though it's not physically possible.
The other possiblility is a compound or composite. If you want to call it lerite, it could be a mineral like Superman's kryptonite. There are many minerals formed of very mundane elements that have very distinctive properties: lapis lazuli / lazurite, opals, zeolites, and asbestos to name a few.
If you want to invent something new that is magnetic, it could be an organic compound, either synthesized by humans or other inteligent life, or by biological processes. for example you can have ["plastic magnets"](https://en.wikipedia.org/wiki/Plastic_magnet). There are microbes that swim in a certain direction according to magnetic fields, and no-one knows how they do it.
[Answer]
Your best bet would probably be [Dysprosium](https://en.wikipedia.org/wiki/Dysprosium). It's barely magnetic, but does fall under the ferromagnetic category, and is less vital than pretty much any other element in that category.
I might remove the "science" tag from your question, though, because "allowing organisms to use telekinesis" isn't within the bailiwick of any element's natural properties.
(I should note that the atomic number of the element would *have* to be the same, so you'd have the same number of protons, the same electron orbitals, and presumably much the same chemical properties, if that matters to you.)
[Answer]
**Walks up to periodic table. Crosses out hydrogen and replaces it with onegen. Universe fails to implode and nobody gains telekinesis.**
You can do it, but it wouldn't change physics. The periodic table has no magic powers to control physics. We could've easily defined elements by neutron or electron count. So all you'd be really doing is producing an alternative history which is clearly not the focus of your question.
So let us go back to the drawing board and think about what in physics acts like telekinesis. Answering *that* will be more useful than defining unobtainium and then trying to explain why telekinetic machinery doesn't exist. After all one of the primary principles of biology is that no particular molecule in a lifeform is in any way not producable artificially with the proper circumstances. Certainly physics would've discovered it.
So what is telekinesis as a *physical* concept?
It is an invisible "force" that moves objects.
It doesn't discriminate between metal/nonmetal objects.
Depending on the version weight/mass is irrelevant for a telekinetic (but possibly volume).
This is literally the description of **gravity**. So telekinesis can somehow theoretically manipulate gravity. However, gravity is not a true force. It is a pseudo force due to space time curvature due to mass. A pseudo force is like when you turn a corner at high speed in a car and feel yourself being pushed inside the car. You are not. What is actually happening is that the car is accelerating away from you (changing direction) and **sliding into you**. It is the result of observing a physical event within an accelerating frame of reference.
Anyways space time is a 4-d "surface" in our 3-dimensional space and the 4th dimension is "time" (not quite as I am not a physicist and dont know the details). I believe it is quadratic/polynomial but that might be me misunderstanding. Basic principles you need to know are this:
It causes gravity.
Mass distorts it.
Light travels along its geodesics
A geodesic is the topological/geometric concept of "drawing a straight line on a connected surface". This means that telekinesis distorting spacetime will cause weird light phenomena. Expect people to "see" around a corner because spacetime bent weird. Furthermore all light phenomena (reflection,refraction,moving slower when not in a vacuum,etc.) are due to space time bending around mass. So telekinesis also allows for general light redirection and refraction. They cannot isolate a particular photon but if we consider photons to be "trains" then telekinetic people can arbitrarily move the "tracks". Remember light moves so fast it is essentially instant motion on Earth so nobody can grab a photon.
So how can telekinetic people distort spacetime?
Simple: mass
Somehow telekinetic people are connected by some kind of mental link to a completely vegetative lifeform that lives essentially extra-dimensional. When they use telekinesis they are just making the creature move by commanding it. It has to obey because the symbiotic relationship between early single cell life on earth and this billions of years old functionally immortal lifeform. It gave cells an advantage by giving them mass to move that would essentially distort spacetime due to sheer and utter *mass*. As a result the lifeform would recieve natural sunlight as all light be funnelled past its distortion. Think of a cosmic whomping willow tree that makes wormholes and gravity distortions just to get sunlight for photosynthesis.
As a result, this creature is sometimes referred to as the so called Yygdrasil or world tree and is the "source" of all psychic power. It isnt a special particle that produces telekinesis. It is just a tree so large and so dense that it can manipulate gravity by the command of people having ancient yggdarite cell proteins being produced by their body so that the tree with respond appropriately. It is basically spatial pheromones. When it senses them it decodes them like dna and uses that to determine where to distort spacetime so it can collect light. Perhaps as humans use more telekinesis the tree will adapt and stop responding to indoor telekinesis. At that time, people will probably speculate that telekinesis is a power granted by the sun. Ah if only they knew!
[Answer]
What you could vaguely hand wave around is [Nuclear Energy Levels](https://www.quora.com/What-is-the-concept-of-nuclear-energy-levels-in-a-nucleus).
In this case, we take an existing element, and add energy to the nucleus to put it in an excited state. Now, with a bit of hand waving, we say that the organisms involved have structures inside their brain cells that can direct the collapse of these nuclei into their ground state or raise them into an excited state.
The excited state would, in this scenario, have an extremely strong ferromagnetic effect that could be directed - since the organism could control the generated field at the atomic level. Since all materials have some sensitivity to magnetic fields, this would be the basis of your telekinesis.
This is not absolute hand-waving, at least in that [chemical processes can affect nuclear decay](https://www.technologyreview.com/s/416009/do-nuclear-decay-rates-depend-on-temperature/). So it's just possible that a protein tightly bound to a heavy metal atom could influence/detect nuclear energy state changes. I'd pick an obscure heavy element like Iridium, you don't need a 'new' element.
[Answer]
What do you mean when you ask "can I"?
If you mean, is this scientifically possible, the answer is no. The periodic table isn't just a random collection of elements put together in an arbitrary order. An element's position in the periodic table determines all sorts of attributes of that element. When Mendeleev proposed the periodic table, he arranged elements to fit the available spaces, and he noticed a number of gaps. He then theorized that these gaps represented elements that had not yet been discovered. He described what the properties of these elements would be, things like what other elements they would combine with, density, freezing and boiling points, etc. When other chemists found these elements and they fit Mendeleev's predictions, that was strong evidence that his theory was correct. Thus, any element appearing at a certain location in the periodic table MUST have certain properties.
But if you mean, if I need a new element with certain properties to make my story work, can I pretend it exists? At which point one can only say, or what? The Novel Writing Police will not arrest you for inventing a fictitious element. I doubt that a horde of chemists will form a mob and attack you in the street.
The nature of fiction is that as long as you state your premises up front, and make the rest of the story follow logically from that, the reader will generally go along. You only alienate the reader if you wait to introduce made-up facts until the time when they're needed to make the story work. Like, if at the beginning of a mystery story you mention that the victim always wore red socks, and then at the end the brilliant detective refers to this crucial clue to solve the case, all fair. But if you never mentioned it before and suddenly at the climax of the story the detective says, "And as the victim always wore red socks, therefore ..." and this solves the case, the reader is going to feel cheated because you brought this in out of nowhere.
[Answer]
I think that it could replace niobium (45) on the periodic table because it is already magnetic and isn't used quite often because it is so strong. Not many people know niobium that is why. But that is all theoretically speaking because nothing can be taken away from the periodic table because every piece is important. Also it is possible to have a stable element after element 118. This is called "the island of stability" but is still to be proven.
[Answer]
Lo and behold, a magic portal opened from the plane of same but different!
Protons on this plane do not exist but are telekons. They share similar properties to our universes protons, but some strange kind of vibrational sensitivity to electro magnetic waves.
By use of stellar power/nova's/science thingimajig atoms were constructed using telekons in stead of protons. They behave the same like elements constructed with protons chemically, they only have the strange vibrational sensitivity to elctromagnetic waves, causing extra electrons to be created from the wave to a steady current. How this is done by the material is sadly not understood due to incompatible equipment to study telekons in our universe. We can only observe it's effects.
Of course the first implementation used when this material was discovered was to make infinite power generators. after an accident in a factory some employees inhaled too much telekon oxygen which caused them splitting headaches and great confusion as they could suddenly see things they normally couldn't see as their brains were flooded with the currents generated by the telekon oxygen. Some of them never recovered and died because their brains shorted out.
Long story short, a lot of properties were discovered, making mixed molecules of telekon based and proton based atoms useful for different harmonics and manipulations.
Some combination, kept secret by the world goverment enabled the cops to read minds by interpreting the electro waves generated by impulses in people's heads.
[Answer]
I first thought at the bio chemistry level, then I realised.
Choose an element and instead of the protons/neutrons being made of three quarks, make it out of 4 or 5 quarks, as scientists like to do. Or two quarks.
>
> A pentaquark is a subatomic particle consisting of four quarks and one
> antiquark bound together.
>
>
>
<https://en.wikipedia.org/wiki/Pentaquark>
PS The antiquark is not an antiquark of the other three quarks so it doesn't annihilate .
If ions and isotopes are already taken I'm at a loss to know what to call elements, like iron, with weird quarks.
[Answer]
What makes an element behave physically and chemically as it does is in the end not the number of protons, but how many electrons it has in the outer shells. An example is platinum and iridium, which are physically and chemically almost identical because the outer two shells of electrons are the same, and if you buy a platinum ring, you can be sure that about 10% of it are iridium. (Additional or missing neutrons change the specific weight, and make the atom more or less stable).
It might not be entirely impossible that there is an atom where the electrons can be arranged in different ways, leading to different physical and chemical behaviour.
[Answer]
Consider that for the Star Trek universe, writers, perhaps Roddenberry himself, invented dilithium (for power), duranium (structural material), and [kironide](https://en.wikipedia.org/wiki/Plato%27s_Stepchildren) (confers psychokinetic powers), completely handwaving any relationships to real-world physics or chemistry. Also completely handwaved was how McCoy could concoct a kironide injection for Kirk and Spock and how it worked to enable telekinesis.
Perhaps there is no need to dive so deep into a plausible description of your fictional substance and its mechanism of operation.
] |
[Question]
[
The Hegemony is a global government governing Earth and her colonies. As a global government the Hegemony has a rather large police force (the Hegemony has merged the military and police within the bureaucracy) numbering in the hundreds of millions.
The Hegemony also maintains/condones a large bounty hunting network across Earth and the colonies. To be a bounty hunter all one has to do is pass a simple background check and get issued a permit by the state. The permit gives the hunter in question the legal right to arrest their target (since their target would already be marked a fugitive).
But why? Are there any practical reasons to have a large bounty hunting system when you already have a large police force?
Note: for the most part peace keepers (Hegemony police) are a benevolent force that plays it by the books.
Permit allows hunters to also pick up missing person's cases if that is a factor in any answers.
[Answer]
Bounty hunters only get paid on results. If they don't succeed, they make nothing and cost the government nothing as where police get paid on success or failure.
Basically bounty hunters are police that work for commission.
The government have enough police to handle most of the routine work but if it starts to get time consuming, they sub it out to bounty hunters. This way they can maximise the return for their money.
An additional bonus is the government has plausible deniability if a bounty hunter uses "questionable" methods to get results. No need for police to beat suspects with phone books and trample suspect's rights (when a bounty hunter will do it for you)
[Answer]
Unregulated Space(s)
Your police force has a heavy presence on-planet, or in dense population centres, but not outside of that - the void between colonies or the wilds of the sparser planets do not have the same infrastructure or law enforcement.
This makes those same locations the perfect hiding place for criminals and outlaws. Bounty Hunters are able to operate in those areas without the Support Network that the Police rely on.
These "buffer zones" also keep the different Departments of your Police Force from coming into conflict with each other - it is always clear which jurisdiction you are in.
>
> Space is big. Really big. You just won't believe how vastly, hugely, mindbogglingly big it is. I mean, you may think it's a long way down the road to the chemist, but that's just peanuts to space
>
> [The Hitchhiker's Guide to the Galaxy](https://en.wikipedia.org/wiki/The_Hitchhiker%27s_Guide_to_the_Galaxy)
>
>
>
[Answer]
>
> Note: for the most part peace keepers (Hegemony police) are a
> benevolent force that plays it by the books.
>
>
>
You actually answered your own question. The setup you're describing would actually be a potential solution to a LOT of the problems that exist in our own society right now.
Basically you're talking about privatizing SWAT, as well as the more offensive arms of the FBI, the DEA, and the ATF.
It's hard to maintain a benevolent police force when one of their responsibilities is trying to control dedicated criminals with no compunctions about using violence. Inevitably the demands of the latter cause your police to become cynical, ruthless, and even corrupt.
Your solution leaves a large, well funded police force handling all the normal 'Protect and Serve' functions and PROTECTS those police from having to deal with heavily armed criminals and gangs. This keeps them benevolent and removes the pressures they might otherwise face to throw out the book in the pursuit of results, or even their own safety. They play it straight, they do the investigation and identify the threats, and put bounties up on them.
Then your heavily armed, licensed bounty hunters go out and THEY get to risk their lives trying to handle the tough criminals. Most importantly, your bounty hunters wouldn't be protected by any laws regarding use of force in the service of duty, which means that if innocent or unarmed civilians are getting shot, it's not a government employee that did it, and it's MUCH easier to throw that contracted bounty hunter to the wolves and let him rot.
Honestly it's a pretty good idea. I might steal it.
[Answer]
Another possible concept would be that police and bounty hunters are pursuing different kinds of fugitives, e.g. police searches for persons who are not yet convicted, while bounty hunters search for those who have been sentenced by the courts to prison or death penalty.
Since the police 'does not kill', the bounty hunters execute the death penalties as soon as they catch the convicted. And since these criminals should already be punished, excessive force is authorized, but frowned upon within the police.
[Answer]
High bureaucracy.
Police can be numerous, but they are bound by countless rules and regulations. Particularly, when a fugitive runs away across district lines, it takes a long time to get other district's force to act on the case. Also, ex-territorial forces (similar to FBI or US Marshals that normally handle this kind of job) are very limited because Hegemony is afraid to make an all-powerful law enforcement agency.
As a result, hunting of fugitives is outsourced to private contractors, who are not limited by district boundaries and not organized to present a threat to the Hegemony.
[Answer]
Simple.
When $$ are involved, bounty hunters are a thing.
We currently have a large police force right here in the good 'ol USA. And yet--we still have bounty hunters. If you ask why that's true in real life, you'll have your answer.
Here's how it works here:
>
> Yes, bounty hunting is legal, although state laws vary with regard to the rights of bounty hunters. In general, they have greater authority to arrest than even the local police. "When the defendant signs the bail bond contract, they do something very important. They waive their constitutional rights," says Burton. "They agree that they can be arrested by the bail bond agent. And they waive extradition, allowing bondsmen to take them to any state."
>
>
> All the bounty hunter needs to make an arrest is a copy of the "bail piece" (the paperwork indicating that the person is a fugitive) and, in some states, a certified copy of the bond. He or she doesn't need a warrant, can enter private property unannounced and doesn't have to read a fugitive his or her Miranda rights before making the arrest. But there are rules and regulations to the job. The bail bond contract gives bounty hunters the right to enter the home of a fugitive, but only after establishing without a doubt that the person lives there. They cannot enter the homes of friends or family members to look for the fugitive.
>
>
>
In real life, bounty hunters go after people who have jumped bail (basically, that means that you haven't shown up to court after the court released you. When you, the criminal, sign the bail bond contract, you waive normal rights and give bounty hunters the ability to track you down in ways not normally available to police.
You might be advocating for a different system, something along the lines of a rewards system, such as what the FBI does with their MOST WANTED. That's completely different and has nothing to do with bounty hunters.
In that case, what you would need is lots of $$ being poured into the system, a government that wants order and is willing to pay for it.
To have a lot of either system (Rewards or Bail Bondsmen Bounties) you need a lot of arrests, and motivation to jump bail or run. Motivation can come in the form of unjust punishment or a corrupt system.
I have to say that in real life, bail bondsmen don't want high flight risk clients. They would rather you didn't run, but they will chase you so that they can get their $$ back (at least some of it). And they don't go after any fugitives, they go after the ones that their company put money up for...
Current rate in the US is something like $50,000-80,000 a year. A decent paycheck, but not enough of a trade-off for it to be worth the risk to most people. You want to make it much, much more profitable or have a more desperate/poor population to make it worthwhile.
The difference between the police and bounty hunters in fiction should be risk vs. reward. In real life, police have a risky job, but actual bounty hunters are actively going after desperate fugitives who have fled. Police sort of take things as they come. Police arrest, bounty hunters apprehend AFTER arrest. In a fictional world cops should be saying something like "Pfft, I'm not going in there--let a bounty hunter take it." Cops should get less $$ but take lower risks, and bounty hunters are less bound by law than they are. That's why in real life there's a sort of love hate relationship between bounty hunters and the cops...
[Answer]
**Rich and poor**
Police is not here to protect every person from violence, it is here to enforce law. (Already ruled and practiced in our world.) In the future there is big difference between those rich and those poor.
There are hight-tech citites (or enclaves), where the rich lives, protected by police and without the need to violently resist (as they could lose their status). The police is benevolent, as usual crimes are white collar crimes (tax evasion and such - solved by penalties) and ocassional interpersonal violence in affect (cheated husband would broke nose his wife and her amant when catch them in flagranti - and then give himself to police without fight - and get away with huge sum to fix cosmetical damage and emocional hurting, maybe even few weeks or month in nice prison - nothing to risk life for). And the police is benevolent, as there is no serious resitance and we are talking rich peoples. In city is total surveliance, cameras everywhere, credit cards with names on them only accepted and so on - nearly impossible to run away from police for more than few hours anyway in bounds of such city.
The cities have good guarded borders and crossing the borders (both ways) is generally frowed upon and is matter of checks like taking intercontinetal airplane today.
Outside are "slums" with poor people, left to themself. No state cameras would stand long there, risky for police to go there without big group and military equipement. Law there is more encorced by customs. Cash is used regularry, IDs are not mandatory to live there and violence is part of the life (also vendetta, low mob mafia, and such).
Well some people are very rich there too, as well as in the city are not-so rich people (gardeners, maids, basically all services) - but those in cities are controlled and wants to keep their good status, those in slums wants to keep their independence and privacy (or are forced to). (basically average person in "slums" can own more, than the lower class in city, except the safe environment and guaranteed good life, including medical care)
There is possible migration both ways, but it is difficult to change status:
**poor to rich** means give all your privacy, be penalized on all proven crimes and be subject of long time suppresion of police as unttusted person - also you need somebody rich to promise overlook over you (and pay all eventual fines for you) and you would go to the bottom positions anyway and basically be slave for years before having chance to get better position, while your patron can send you back to slums on his/her whim (so you would lose everything in both words)
**rich to poor** - well, if you think you can survive in jungle, where nobody helps you and everybody hates you, without all those nice thinks you had in city guarantied - you need to be really desperate to go this way - and the city would not like to accept you back. Also all your relatives would lose a lot of credibility aand status for your action, even if they disown you - do not count on some support.
Anyway the cities needs the slums for taking care about agriculture, mining, low tech (which does polution), artworks and such, while slums need cities for high technology, medicines, movies, etc. so there are big trade routes both ways.
And those bounty hunters operates outside the cities, both for locals and citizens, who had problems outside city walls. Maybe even some bounty hunters have homes in cities and high technology (private SWAT), but the main body lives in slums and knows the back streets, gangs and all others, who operate there.
Bounty hunters are not allowed to operate in cities (the police can manage it there good enought), but police cannot operate in slums (as nobody cooperate there and small units would be attacked for equip and ransom, while big units have no chance infiltrate anything), where bounty hunters can move freely as locals. There is tell-telling difference between citizenc and locals not only in body modifications and equipement, but mainly in behavior, street knowledge, language ... they both just stand out on the other side of border.
**Referencies:** District 9, Battle Angel Alita, Demolition man, Ghost in the Shell, Black Lagoon, ... (or with some exgregation rich countries (as "cities") vs poor countries (as "slums") today)
---
Edit: It is just on you, what "poor" means in that setting - if common food is soya-ratburgers as real meat (even from vermints) is too expensive, or if it means, that some of them have "just" 2D TV without tactile feedback, only a two or three pieces of cyberware enhancements and have to travel by ground vehicles ... poor and rich is just relative to each other.
[Answer]
1: "He Bought The Farm"
As far back as the Roman empire and probably beyond, it was recognised that the greatest danger a regime - if not a civilization - can face, is a large number of idle hands belonging to people who have some training in tactics and weaponry and combat experience. It gets worse if they're angry for whatever reason at the current government. To 'combat' this governments began such programs as formalized medals, veteran support programs and REMF promotions, as this regards Bounty Hunters: With such a large military and police force come a lot of retired police officers and soldiers, finding ways to keep them busy is a reason to spend money, let alone if it provides corollary benefits.
Bounty Hunting offers a good professional translation because it can be done part-time(most wanted won't even leave their home neighborhood) and the individuals will already have training in at least a significant proportion of the requirements of the trade, giving them a 'leg up' over other applicants. It will also make them unpopular among the residents, which hinders their inclusion among the part of the community most likely to rebel.
2: Management
Bounty Hunting work should reasonably be irregular and almost more like a taxi office than a police force, irregularity makes for complex management and if there's anything governments can't cope with it's a nonlinear state. Bounty Hunting firms can 'afford' to be more flexible without endangering their jurisdiction.
3: Risk Mitigation
The people (proportional) most likely to present difficult arrest situations are those who know they're already screwed(skipping bail, etc) it makes sense then to give those difficult arrests to people who you don't mind getting hurt, or blamed for hurting others, as much as possible.
4: Collateral
If a police officer harms an innocent in the pursuit of their responsibilities, the police department, county, state or federal authority risks massive costs in legal fees and compensation. Outsourcing to private industry allows the onus of covering insurance to be put on taxpayers, rather than tax recipients.
5: Payment on Delivery vs Full Time Salaried
A Police Forces number one concern must be the integrity of it's own officers, even after actual enforcement of laws, otherwise it's a liability rather than an asset. Police Officers must not be at risk of going bankrupt despite performing their duties and must be disallowed from 'alternative interests,' being relatively poorer, they're relatively easier to bribe or influence with money even than politicians. Regular, dependable payment is essential. That's to say nothing of the requirement for stations and routes to always be staffed as expected and part-time contracts are just asking for flakes to flake.
6: Diversification
A Bounty Hunter can be free to take on non-government work, private security, investigations etc, whilst government contracts must be on average profitable, a diverse portfolio allows recruitment (and a 'Unity'(working for the State) psychological influence) of people who would normally run a mile at police work and subisidize against failure to secure bonds.
7: Arsenal
A Police Force (bearing in mind the earlier requirement for consistency) cannot (it's hard) easily maintain the capacity to deal with all conceivable eventualities, maintain stockpiles and training regimens with/of all relevant materiel and techniques. If they have a budget to balance more equipment means less beat officers or investigative staff. On the other hand, a private individual might be found at any time that has the required licenses, training and equipment to perform a task and the PD might wish it was legal to Deputize, instead they create a contract to a Bounty Hunting team to effectively do the same, getting the results without the overheads for scarce or one-off operations.
If you follow this to it's logical extreme you don't need an army - a police force, contractors and monopoly over space-borne weaponry will do. Even, one might argue an army on the scale of millions of personnel is surplus to requirements if one exists as the sole political entity in known space. No traditionally scaled(that is to say, a tiny fraction of the population actively involved, supported by a few rich folks aka Rev. War) rebellion opposed by the military could hope to succeed in developed nations in modern times(without external support), let alone in times when you can't even see the enemy you're wanting to oppose.
//Military Reserve
Whilst the Hegemony might feel secure in it's integrity, space is big(?) legalizing(promoting, institutionalizing) bounty hunting provides one more method of maintaining a certain core of military readiness that otherwise would not exist.
The Army and 'Navy' might well have biannual mandatory refreshers for reservists, but it's not going to be any substitutute for people who train & use the relevant skills on a daily basis. Depending on the nature of the bounty hunting profession in your world, bounty hunters may provide a tangible asset if it came to war. Those who concentrate on domestic non-violent enforcement could be contracted as 'peacekeepers' and police cadre in occupied territory, members of more militant organizations could be constituted as special operations units, or used as consultants for retraining and readiness by a military that has not seen a wartime action in decades.
Even, in such circumstances where the Army has not had anything much military to do for a long while, it would potentially be the case that a great deal of the more pro-active individuals who can't stomach jobs as placeholders or 'potentially useful' would take up bounty hunting and bounty hunting would attract the prestige historically linked with military units.
[Answer]
**It gives people an incentive to turn themselves in**
The police force is known for being generally pretty fair and reasonable. They're constrained by a number of laws. Also, they can afford to be, partially because they avoid the high-pressure stuff. Everyone knows that if you crank the threat up high enough, the police will just let you go. Wave a gun, and you can walk out of there. At the same time, the police are wearing body cameras at all times, and those update the Panopticon Surveillance State System in real-time. If you wave weaponry at a police officer, your name goes on a list, and the bounty hunters come after you.
The bounty hunters are not fair, and not reasonable, and do not wear body cameras, and they will seriously mess you up. There's likely to be a firefight or two, and anyone you care about in the immediate vicinity might wind up being collateral damage. They get a bonus if you're alive when they bring you in, but it's not *that* big of a bonus.
Thus, if you're innocent, or even mostly innocent, it's probably a good idea to turn yourself in. The punishment you'll get for whatever crime you committed won't be as bad as what the bounty hunters will do to you trying to "Bring you to justice". If you're guilty s hell, though... well, that's what Bounty Hunters are for.
[Answer]
# Federal division of powers
Although the Hegemony is a single unified government, in practice it's far too large to be run as a unitary body. It must maintain different levels of bureaucracy, governing areas ranging from cities to what we would think of as countries. Potential competitors for each region's rulers and bureaucrats abound: other regions of similar size, smaller constituents, larger regions they are a part of. Since your police and military forces are controlled by the bureaucracy, they are part of that competition for power.
One natural result is that individual regions of various sizes have their own security forces, with very strict rules about where they are and are not welcome. A nation-like region might not even have the power to send police into individual provinces or cities, depending on whether or not it has a justification that won't make it look like a power play. Because they're effectively in competition, police forces at different levels and in different places aren't likely to have very good communication - this is something that perfectly friendly agencies and nations struggle with in the real world, after all. So criminals (or criminal syndicates) that can move between regions can stay ahead of the local police.
Enter bounty hunters. Unlike police/military forces that represent the encroaching power of a rival power bloc, individual bounty hunters are hardly a threat to the established order. If they cause problems, the host region can easily censure, expel, even kill them without much difficulty. They can take down lone criminals who flee between jurisdictions, and gather information about larger syndicates to feed to the local law. (They might even serve as an informal communications channel for police forces whose superiors are feuding but who must cooperate against a particular threat.)
[Answer]
# Plausible Deniability
What the police do reflects directly on the government. Even a *rogue cop* who goes to court tarnishes the badge. A *rogue cop* who does not go to court means the rot is starting.
I hope you realize that giving the legal right to arrest a *target* means that the bounty hunters have the legal right to arrest anyone who *looks like the target*. And the right to harass anyone who *looks like the target* and demand to see papers to prove that they're not the target. Add that the bounty hunters are not trained police officers, and do not get access to police information systems. Either rules are harshly enforced on the bounty hunters, then the first honest mistake sends them to prison for kidnapping and assault. Or the system cuts them some slack if they say "he looked like the perp, honest." Such a force can be useful to people in power.
Note that many jurisdictions allow a [citizens's arrest](https://en.wikipedia.org/wiki/Citizen%27s_arrest) and many post rewards for information on crimes or criminals. But someone who makes a living by seeking out opportunities for a citizen's arrest would be in an awkward position if he or she gets it wrong.
# Lobby Work by the Bond and Prison Industry
The US-style concept of bounty hunters is tied to the practice of bond/bail and the agents who loan this money. Few industrialized countries have similar systems -- a defendant is considered innocent until proven guilty, and held in jail **only** if there is fear of flight or evidence tampering. Posting a significant bond might reduce the fear of flight, but not if the defendant fears several years in prison.
So why keep it? Because the people involved in it make lots of money, and donate in the right places.
[Answer]
**Standing armies are dangerous to a polity.**
>
> A standing army in the hands of a government placed so independent of
> the people, may be made a fatal instrument to overturn the public
> liberties; it may be employed to enforce the collection of the most
> oppressive taxes, and to carry into execution the most arbitrary
> measures. An ambitious man who may have the army at his devotion, may
> step up into the throne, and seize upon absolute power.
>
>
>
[The AntiFederalists on Standing Armies, Laurence Vance](https://www.lewrockwell.com/2007/05/laurence-m-vance/standing-armies/)
Your police and your army are one entity. The writers of the Constitution dreaded having a standing army at all; now the US has one, but there are strict restrictions on its actions and especially its interaction with the populace. On those rare circumstances when armed troops are needed within the borders of the US it is the milita, or National Guard who is called - civilian soldiers, not the professionals.
Having the military interact with the public is dangerous. It is also dangerous to a civilian power structure because the army can simply seize power.
**Your armed forces / police force are bound by many rules of interaction which are meant to reduce the danger they pose.** Bounty hunters interact intimately with the populace in a way you do not want your military to do, but they are just one aspect of the workaround in this world. Just as in our world paramedics, fire fighters and animal control are bodies of public servants (and possibly volunteer part-timers) who can be called out to help people, so too in your world the bounty hunters, traffic control persons and other aspects of civil society control.
Musing further - their mandate is violence in service of the State and so calling the police / army in your world is tantamount to calling for a person to be killed - because more often than not that is the result when the police / army arrives at the scene. This scenario would make for good high science fiction - exploring our real world from the perspective of a fictonal one. Those interested and aware of current events in the US can consider these aspects of law enforcement as they see fit.
[Answer]
I'd imagine they target different demographics.
The police presence would be largely urban, tied into their support networks and fortresses (stations). In the future this would include megalithic surveillance networks and sensors.
The bounty hunters would go where its not cost efficient to set up the supporting infrastructure (yet). Deep country, swamps, off planet, asteroids. Places they haven't built up yet. Or perps that cant be suppressed with standard urban loudouts.
This means seeing a bounty hunter on a city job would cause friction with local cops ("What's he doing here", "Just as bad as the collars he brings in")
[Answer]
## The average citizen is extremely dangerous
Imagine a world not too far into the future where most people own a 3D-printer/replicator, and the personal technology/cybernetic enhancement fields have advanced to a point where people can be stronger and quicker almost without limit.
We have gone post-scarcity, AI governs most high-level systems, leading to a lack of jobs. People get bored, turn to crime for something to do. Those that don't can join the police, solving petty crimes like vandalism, theft, lollygagging etc.
However, the organised crime aspect of the world becomes extremely dangerous, any citizen could print themselves gun parts, and enhance themselves to have super strength and speed. Why would police hunt down these dangerous criminals when they don't *need* to work? The world is post-scarcity, remember?
That's where the bounty hunters come in. An elite organisation/guild of mercenaries who are also cyber-modded to high heaven, equipped with the very best weaponry. All the government has to do when there's a murder or terrorist attack is post a bounty on the offenders, and the guild will do the rest.
[Answer]
See [this answer](https://worldbuilding.stackexchange.com/a/125632/28494) to the question, "*How to police a state with high amount of gun ownership where the police are not routinely armed?*" -- because the opposite scenario to that might be that it's difficult to police a world where you DON'T have ubiquitous surveillance, and/or where it's easy for private passengers to cross international borders unchecked, and/or where cash is king (or something like cash, i.e. valuable, portable, anonymous, and with a reasonable shelf-life -- cryptocurrency, medicines, or whatever).
Local police work (by definition) against local crime and criminals -- and have no personal experience off-world -- so if ever you want a detective who's hot (or cold) on some fugitive's tail as they flit from one place to another, or try to make a new life elsewhere, that would have to be someone else, e.g. a bounty-hunter.
I don't think they're for "high-risk" arrests because, instead, professional SWAT teams can handle those (and the function of whatever is left of the military is to handle whatever a SWAT team can't).
[Answer]
The answers by Thorne (about the monetary advantages) and Morris the Cat (about the practical benefits to the safety and 'purity' of regular law enforcement) are both great, and cover what I would think are two of the biggest aspects here if you assume a government that isn't fascist and/or authoritarian.
There's one other really big advantage though:
### Once you go interplanetary, you have too much space to cover with traditional canvas policing techniques or even regular patrols.
Quite simply, it's impractical to have law enforcement that comprehensively covers anything beyond planetary orbit, or at most beyond a given star system and established travel routes between systems. There's just way too much area to cover. Even if you had your *entire populace* providing conventional law enforcement, you *still* wouldn't be able to reliably cover all your territory. Given this, once you get past planetary orbit, you either need a dedicated force that can track down and retrieve (or terminate) fugitives, or you just treat them as exiles (that is, standing warrants for their incarceration or execution if they show up in areas under jurisdiction of your police, but nobody actively going after them).
This also accentuates both of the aspects of the answers I mentioned above. As the area you need to cover goes up, it makes more sense to pay based on results, and you end up with more and more places for isolated groups of very dangerous criminals to exist.
This aspect of needing an impractical number of officers proportionate to your population to cover a given area is a large part of why bounties were the norm in the American Old West, each town had maybe one or two law enforcement officers, and it was just impractical for them to chase down every last criminal that came through town. You can see the same logic to a lesser extent in the existence of organizations like the US Marshals, there's just too much area for the regular officers at the level of jurisdiction at which they operate to properly cover.
While it's not exactly the primary reason, you can see this in play in a *lot* of science-fiction settings as well. In Star Wars for example, there actually are planetary and system law enforcement agencies, and even galaxy-wide ones, but bounty hunters are still common enough that outside of certain 'special' areas (the corporate sector or deep core for example), you're more likely to run into them than you are regular law enforcement when traveling the stars.
[Answer]
**Cost**
If you have a detective squad, they'll be busy inside their jurisdiction working on several cases. Cases go cold and get dropped, police have the safety of their wards as a high priority.
Depending on the bounty system you can either
A. Assign bounties to hunters specifically, give each a number of them to accomplish and no real timeline. If they complete the task they get significant pay,less than a dedicated detective squad working the task full time, but plenty for a single individual. The reward is set and the time/resources used are up to the contractor to work out. Other answers have mentioned this.
B. Open bounties, anyone who completes a bounty can claim the reward if they're licensed. Once again the reward per task is static and the investment of resources is on the hunter themselves, failure doesn't add cost to the police themselves.
**Specialization**
Hunters hunt bounties, they don't do traffic stops, riot suppression, emergency response or anything else. They can spend time on the job because they're specialized and have contacts and licensing to navigate complicated jurisdictional boundaries, they can afford equipment specifically for tracking and hunting people. Their main income is supported by these things, a police department couldn't and shouldn't afford such things at scale.
**Networks**
I mentioned them above but a network of contacts that aren't strictly legal would benefit a bounty hunter and a truly squeaky-clean PD can't be caught doing that. Hunters might network with one another, collaborate on jobs or simply share resources in a way that would not flourish in the bureaucracy of a megacity PD.
**Danger**
Bad folks are gonna kill cops if they're desperate enough, we need cops for a lot of things that aren't hunting fugitives. Better to pay folks that know the risk and chose the line of work than wear out cops you need for more humanitarian cases.
**Range**
Sending a cop far outside their jurisdiction or into seedier areas with a badge risks the officer and almost guarantees failure since they have no effective authority in such a place. Bounty hunters are more discreet because they don't have legal obligations like an officer.
**Jurisdictional Respect**
Sending an officer from my PD to your nation is little problem if we're friendly(Mounties in the US, FBI in Canada, neither are PD but you get the idea), might be a problem if we aren't. Could get some nasty legal battles if we disagree on how something must be handled.
If there's some sort of central registry of bounties that all nations/jurisdictions share, then hunters can collar fugitives anywhere in the world.
Alternatively a bounty hunter might be willing to cross a border, shoot the bad guy and just leave. It's far less of a risk to international relations if a third party that has no official status in my PD gets caught snagging fugitives on a bounty.
[Answer]
The police tend only to do things that are cost effective. They won't go look for your stolen bike even though they know likely locations where it might be stored or for sale. They won't devote more than a certain amount of effort to finding your mugger. They will stop pursuing a fugitive if that fugitive makes it too expensive. They won't try to arrest someone who ripped you off over the internet if they are in a different jurisdiction.
Perhaps it is worth it to me to pay a bounty hunter to do any of those things. Perhaps I'm happy to pay 1000cr to a bounty hunter if I can get my bike back or 50,000cr to get one to track down the man who killed my wife and then disappeared in to the underworld. Maybe a community will club together to pay for a bounty hunter to find the man who said he would broker the sale of their crops and then disappeared with the money.
If you want to differentiate bounty hunters from hired guns you still need the licences and rules that they must follow. So you can pay one to retrieve someone charged with a crime so that the police can arrest them but you can't pay one just to beat up someone you don't like.
This is effectively justice for those who can afford to pay.
[Answer]
Crime, crime and more crime. Why? A black market in a key thing that spawns an underworld that makes prohibition and the drug war look like a tea party (e.g., perhaps touching is a crime, as in the comic [Love Not Found](http://www.lovenotfound.com/about.php); but, unlike the comic where everyone thinks touching is gross, in this world everybody wants it but no one admits it and all touching is covert).
It might be a bit like many aspects of life in the modern People's Republic of China (a [2018 Forbes article](https://www.forbes.com/sites/ralphjennings/2018/03/15/corruption-in-china-gets-stuck-half-way-between-the-worlds-best-and-worst/#7d8e651273d1) captures the feel of it). A totalitarian regime requires lots of watchers. But actually getting things done in a bureaucratic mess like that might take rule breaking bounty hunters.
Extreme economic inequality also creates demand since a lot of gatekeepers and guards must be hired to protect the privileged from the *hoi polloi*, and the elites then have $$ to hire bounty hunters with better results and service than bureaucratic law enforcement (compare [Altered Carbon](https://en.wikipedia.org/wiki/Altered_Carbon_(TV_series))), not unlike hiring [private judges](https://www.americanbar.org/groups/dispute_resolution/resources/DisputeResolutionProcesses/private_judging/) (which exists in real life) with more time to focus on their concerns. Maybe the elites have private prosecutors too.
The two ideas aren't incompatible with each other either.
[Answer]
A short answer is make it challenging to make an honest living and criminals will be numerous. This encourages people to take employment such as bounty hunting as well. Secret Police and informants can be a cheap way of making a highly populated police force and help create an atmosphere of fear and powerlessness. You don't even need to make them fulltime servicemen either.
A corrupt version could be paying for testimony so you can execute someone to set an example...
[Answer]
Another option that I haven't seen mentioned yet is separation of duties. The "Police" branch of the Hegemony's military could be mostly (or entirely) detectives whose job is to determine what happened, who did it, and if it was illegal (in most cases that last one is obvious, but think accidental death vs intentional murder). These people get paid for work done regardless of bodies brought before a judge (or straight to jail). After the police determine something illegal happened, they refer the person to various bounty hunters (or BH networks) who get paid upon bringing the suspect into the system.
Still another option are jurisdictions. Police are bound to an area while a bounty hunter isn't (current world example would be crossing countries to bring someone to justice). That does come with it's own set of legal issues, but that's the hunter's concern, not the cop's.
[Answer]
In the United States, this already exists. Police regularly offer sums of money to anyone who can provide information that leads to the arrest and conviction, banking on a criminal's friend to say "Hey, I think I know who your bank robber is: My buddy has income he can't explain, he paid in multiple large bills... the serial numbers are sequential, and he was drunk at my place last night and said 'I robbed the bank and there's a reward out for me!'. Can I get paid?"
In addition, most common law jurisdictions (basically any country that has it's national origin ties that are related to the United States or The British Empire... serving justice to over 1 billion people daily) have "Citizens Arrest", which basically allows any Joe Schmo to "Arrest" a person who they have a reasonable suspicion of committing a crime... it's frowned upon, but it's not out and out illegal (for a few reasons... it's easy for an untrained citizen to arrest someone in a wrong manner and get the case thrown out... it's dangerous to arrest criminals even if you are a cop.).
Finally there are real life bounty hunters today that work for the police (Almost entirely in the U.S.). Normally the work is done for privately owned "Bail Bondsmen" who are basically loaning criminals the money to put up bail. If they don't pay back, or don't show up to court, the Bondsman will call in a bounty hunter who can go and recover the criminal. Since most of these individuals are not officers of the peace, they don't need warrants to enter property and anyone can citizens arrest. I'm not as up on this enough to post more about the system, but only four U.S. states outlawed this practice.
[Answer]
To have bounty hunters you need somebody who has interest in catching the fugitives but cannot use the law enforcements agencies to do so.
In the mythical old west this was because weak police presence, in modern US because it is about a private company enforcing the contract it has with the fugitive.
In your case we can exclude the first option, so we can assume that somebody other than the government pays the bounties. Since you are talking about "a network" we can assume that it is the network paying the money and choosing to pay bounties instead of a salary or a wage.
So three conditions for practical bounty hunters.
1. Private economic interest in catching people, the government does not do it.
2. Interest in accepted by government as legit, so the police do not stop it.
3. The interest is irregular enough that normal employment is not a good option.
The conditions are interconnected. The reason it does not make for normal employment and that the police do not do it are probably related. The private interest and the reason the government accepts it are also probably related.
I hate to say this but this kind of implies some not nice things about the state. Basically, the state is choosing to let a private entity to exploit a specific demographic and looks the other way as long as the private entity keeps it informal by handling it on case by case or bounty by bounty basis. Since the cases involve only individuals there is no systematic pattern of abuse, or rather it can be pretended that the patterns rise from the legitimate individual actions of the individuals involved not from discrimination. The state is not to blame that this particular demographic has lots of this kind of problem.
So we can reduce the three conditions to two
1. A demographic that is considered "outsiders" by the establishment.
2. An action common in that group that can
a. be monetized for profit, some sort of financial transaction is involved
b. serves as an excuse to look the other way, it is their own fault
At this point you kind of need to do the actual world building and fill in the blanks. What kinds of people are on the bottom of the social and political hierarchy to the point of being virtual (but not real) outsiders? What things does this group do to justify being considered fugitive? How can this be monetized? Then just legalize the enforcement of the private contracts involved in the monetization and you have bounty hunters.
You can easily use the modern US as an example how this works or even as a model but it is your world so you can and probably should do something else. This is because even this answer probably reads to most who read this far as a social commentary on the US. With the current political climate that is only one step from seeing this answer as me pushing some sort of liberal political agenda. You want to avoid doing this unless you either actually want to make a political statement or, as with this answer, want to warn against looking like you are making one when you do not.
Naturally it is perfectly possible to write about bounty hunters without going to the social issues behind it. And if you copy those issues from real life instead of making your own you should IMHO.
] |
[Question]
[
My island is in the Indian Ocean, surrounded by a ring of very sharp rocks. The water is, at most, a few meters deep.
Since a large ferry could not reach the island, what real-world methods of transporting vehicles could get a few (Let's say 7; 3 [Hummers](https://en.wikipedia.org/wiki/Hummer_H1), 1 [RV Mobile Lab](http://jurassicpark.wikia.com/wiki/Fleetwood_RV_Mobile_Lab) and 3 [Caviga Canyon 500s](https://www.motorcyclenews.com/bike-reviews/cagiva/canyon-500/1996/) ) of the machines onto the island?
There are many smooth, flat beaches on the island's coast, so getting them ashore should not be a problem.
[Answer]
Some helicopters are able to transport ground vehicles. Check out the weird Sikorsky CH-54 Tarhe:
[](https://i.stack.imgur.com/0xiqp.jpg)
And this is how it is used:
[](https://i.stack.imgur.com/V7yGK.jpg)
You may also be interested in the Boeing CH-47D Chinook:
[](https://i.stack.imgur.com/lgpGn.jpg)
Or maybe try the Mil Mi 10:
[](https://i.stack.imgur.com/sjH29.jpg)
If flying isn't your thing (it happens), you may use a [Zubr-class LCAC](https://en.wikipedia.org/wiki/Zubr-class_LCAC), which is an obscenely huge hovercraft:
[](https://i.stack.imgur.com/Ex3xE.jpg)
[Answer]
Your regular boats. But first: **plenty of dynamite**.
[](https://i.stack.imgur.com/qIsRB.jpg)
Reef demolition before invasion of Peleliu, WW2.
<https://oceanexplorer.noaa.gov/explorations/18peleliu/background/assault/assault.html>
>
> As careful as the plan was, unless the amphibious craft could get over
> the reef; avoid the mines; navigate the concrete anti-boat obstacles,
> the coral heads, and boulders; and land on shore, it was doomed to
> failure. The Navy underwater demolition teams (UDTs) were formed in
> 1942 in response to this fundamental problem...
>
>
> In the run up to the Peleliu operation, UDT 10 scouted the invasion
> beaches in USS Burrfish. The information gathered in August 1944
> revealed an array of concrete tetrahedrons, a double row of wooden
> posts 75 yards from shore, barbed wire, horned mines and, importantly,
> in some areas the reef was awash with barely two feet of water at low
> tide. Three days before D-Day, UDTs 6 and 7 deployed along the
> invasion beaches to destroy obstacles, but more critically, to **blast
> wide ramps into the coral for the amphibious craft**.
>
>
>
So too your rocks. It is the modern day in your world. Stuff is available to blow stuff up. Use that first stuff liberally on the second stuff. Then proceed.
---
and here I see @RonJohn proposed exactly this in the comments 5 hours ago!
[Answer]
![Ferry with long pier[1]](https://i.stack.imgur.com/oUXLK.jpg)
Build a pier to the place you can safely dock a ferry or other ship. A pier can be as long as needed.
As an example, in 1926, the Golden Gate Ferry Company began construction of the Berkeley Pier in Berkeley, California. It extends about 3.5 miles (5.6 km) into the San Francisco Bay. It was used to transport vehicles in 1926.
Simply build a pier over the sharp rocks out through the shallow waters until you get to a spot that is deep enough for ships to use.
* <https://en.wikipedia.org/wiki/Berkeley_Pier>
* <https://www.geolounge.com/worlds-longest-pier/>
[](https://i.stack.imgur.com/QTeT2.jpg)
[Answer]
In addition to @Renan's answer, the [Bell Boeing V-22 Osprey](https://en.wikipedia.org/wiki/Bell_Boeing_V-22_Osprey) has an internal payload of 20 000 lbs. Might take 2-3 trips, or 2-3 planes.
[](https://i.stack.imgur.com/NsLEF.jpg)
If there's no room to land a plane, and the island is too small for a reliable airdrop, you can also perform a [low altitude parachute extraction](https://en.wikipedia.org/wiki/Low-altitude_parachute-extraction_system).
>
> The low-altitude parachute-extraction system (LAPES) is a tactical military airlift delivery method where a fixed wing cargo aircraft can deposit supplies in situations in which landing is not an option, in an area that is too small to accurately parachute supplies from a high altitude.
>
>
>
Note that the plane here doesn't actually land.
[](https://i.stack.imgur.com/cMAiU.png)
[Answer]
You could use a ground effect vehicle, sometimes known as an ekranoplan. These are plane-like vehicles that use the ground effect, an air cushion that forms under the wing at low altitudes, to achieve incredible lift relative to their wing size and power. Then can only fly a few metres above ground or water, but can carry an immense amount.
[](https://i.stack.imgur.com/4AbD4.jpg)
This is the Lun-class ekranoplan, built by the Soviets as a combination anti-ship craft and assault transport. It could carry a thousand tons of military equipment right up to the shoreline at 550 km/h, and fight with six heavy anti-ship missile launchers that you can see rising from the centreline. On its nose you can see four turbojet engines that provide the primary thrust. It flies up to four metres above the water, so it can avoid all but the largest rock formations.
This fellow is a little heavier duty than what you're looking for. You could probably pack all that gear into this sprightly little fellow, the A-90 Orlyonok:
[](https://i.stack.imgur.com/SOmaH.jpg)
This chap could carry 28 tons of cargo at the not insignificant speed of 400 km/h and is rather more maneuverable than the previous beast. The front hinges sideways to let vehicles roll right onto the beach. I think this would make for a fun and interesting way to get to Isla de Spikeyrocks; at least, as long as you can build your own or pull one out of the Russian plane graveyards.
[Answer]
Maxim 11: Everything is air-droppable at least once.
Hummers are *designed* to be air droppable.
If you switch from the RV to M934 Expansible Van Truck, I *believe* it's air droppable. Certainly at least once.
You could drop the Cagivas (palatalized) as well, or you could use something like this <https://olive-drab.com/idphoto/id_photos_m1030_m1d.php> and it uses the same fuel as the HMMVs.
<https://www.youtube.com/watch?v=oxLi4gKprOo>
If that doesn't work for you, the Marines have a bad ass hovercraft that is slightly smaller than the one listed above.
<https://www.youtube.com/watch?v=XbXF2B3fHMk>
Remember also Maxim 32: Anything is amphibious if you can get it back out of the water.
[Answer]
The USMC has been hitting the beaches with mechanized transport since before WWII, so in addition to simply flying in on helicopters, the Marines can hit the beach in several ways.
The most obvious one is to dispense with carrying vehicles, and simply ride into battle in your own amphibious fighting machine. The USMC uses the AAV-7, which can swim ashore, and then continue inland to battle with a turret mounted .50 HMG and a 40mm grenade launcher, plus 25 armed to the teeth Marines ready to debuss on the objective.
[](https://i.stack.imgur.com/FhHEE.jpg)
*AAV-7*
[](https://i.stack.imgur.com/A9Bvi.jpg)
*AAV-7 ashore*
The Royal Marine Commandos use the "Viking" Marginal Terrain Vehicle (MTV), which is also amphibious, although having lower levels of performance than an AAV-7. It is much more versatile ashore, capable of crossing terrain that no other vehicles can even approach:
[](https://i.stack.imgur.com/9jlD3.jpg)
*Royal Marine Commando Viking MTV*
If you really must transport the various vehicles, the USMC uses the LCAC, a hovercraft which can approach the beach very rapidly, and even fly over the beach and move inland so long as the ground it relatively flat. Getting past the sharp rocks might be an issue depending on the size and sharpness, getting the "skirt" damaged makes the hovercraft much less capable of maintaining an air cushion.
[](https://i.stack.imgur.com/7gRNR.jpg)
*Formation of LCAC's*
Finally, the US Navy and Marines are experimenting with a new vehicle which has many of the features of a Viking and an LCAC. The prototypes are small, but a full sized version is supposed to take cargo as large as tanks from ships, swim ashore and deliver the payload inland. Meet the [UHAC](http://www.navatekltd.com/innovative-products/uhac) (Ultra Heavy-lift Amphibious Connector)
[](https://i.stack.imgur.com/RuVVY.jpg)
*The enormous "paddles" serve as a track ashore*
So if you are looking for alternatives to air delivery, here are how the USMC and Royal Marine Commandos do it.
[Answer]
Depending on the shape of the reef, something like the [PTS](https://en.wikipedia.org/wiki/PTS_(vehicle)) tracked ferry. Formerly Soviet, so you can easily explain a surplus ferry showing up anywhere after the Cold War.
Being tracked, the PTS might be able to climb over reefs that would endanger the bottom of normal boats. But a sufficiently pointy reef could pose problems.
The advantage is that it is smaller/cheaper than a hovercraft, and it uses less fuel than a helicopter. So the expedition might be able to keep it around, for coastal or river transportation.
[Answer]
## A dredge
Park the dredge over some sandy bottom and pump. Sand slurry can be carried some distance. Deposit the wet sand on the rocks.
Water runs off, combat engineers grade it to suit.
Wind and wave action will eventually restore the shore.
[Answer]
What about a ramp that unfolds from the boat? How wide is the ring of rocks? Think of something like a drawbridge or a loading dock leveler.
What about a crane on the ship?
[Answer]
Use a pontoon bridge (if only needs to be used once, and the rocks are just below the surface), or a Bailey bridge (for extended operations, or rocks above the surface).
These are both kit bridges that that can be built very quickly, and were used for temporary bridges during WWII.<https://en.wikipedia.org/wiki/Pontoon_bridge>
There's also the medium girder bridge (folding bridge), and the Armoured vehicle-launched bridge. This is a medium girder bridge which is attached to a tank. It is unfolded and laid at an chasm, and then detached. The rest of the division then cross the bridge, the tank crosses last, and collects the bridge.
<https://en.wikipedia.org/wiki/Armoured_vehicle-launched_bridge>
[Answer]
Swim or kayak in and then set up a cable bridge, Bring the vehicles in piece by piece and assemble them on the shore.
[Answer]
Set up your loaded landing craft at the outside edge of the ring of rocks. Generate a small tsunami with a controlled (nuclear) explosive out at sea and surf over the rocky area and run aground on the beach.
<https://www.youtube.com/watch?v=_ds0XV3ORmI>
[Answer]
How about an icebreaker? Maybe the icebreaker bit would break up the rocks. Or maybe an armored icebreaker so it wouldn't get punctured.
] |
[Question]
[
**Closed**. This question is [opinion-based](/help/closed-questions). It is not currently accepting answers.
---
**Want to improve this question?** Update the question so it can be answered with facts and citations by [editing this post](/posts/166910/edit).
Closed 3 years ago.
The community reviewed whether to reopen this question 1 year ago and left it closed:
>
> Original close reason(s) were not resolved
>
>
>
[Improve this question](/posts/166910/edit)
I am writing a sci fi novel, which is set 100 years into the future (2120). In it, one of my characters is a scientist and investigates a case of SHC where a victim was seen with flames coming from their abdomen/gut, before passing. He writes a report, and he says that in olden times (our present period), it was called Spontaneous Human Combustion, but now it is known by [medical sounding term] instead.
Specifically the cause involves a static spark in malfunctioning nerves in the gut, or a build up of a liquid called diphosphane, also due to a biochemical malfunction in the gut, which can act as an ignition source for the other flammable compounds which exist in the gut.
I am looking for a less paranormal, more formal medical term for SHC.
[Answer]
Just calling it **Knowles Syndrome** would probably be just fine and consistent with current practice.
But if you really want to go with **sudden-onset acute hyperthermia**, feel free.
[Answer]
## Anaphlexis, or autoanaphlexis
(Thanks to AlexP for corrections)
I got it by going into Google Translate and trying to get latin for combustion. It was *combustione*, I didn't like that. So I tried greek next (the other language that is used for most scientific terms). Didn't like the first term I got (*kaf-si*), but the second one sounded sciency. It was "anaphlexy" (with the "x" sounding like "ks", so pronnounced more like "anaphleksy").
For the record I can't read greek to save my life. The actual word came out as ανάφλεξη, I am typing what I heard when I clicked the speaker icon.
I thought that making it end in "is" would make it better due to the [Rule of Cool](https://tvtropes.org/pmwiki/pmwiki.php/Main/RuleOfCool). Turns out that ancient greek had final *"is"* as a thing, so no RoC needed here. Thanks Tanner Swett for the info!
---
But seriously, nobody does it better than marvel. If you tell someone who is neither a scientist nor a Marvel fan that you are a physicist and that you are doing some experimental research on Pym Particles, they might just fall for it. You think that even Marvel fans wouldn't be fooled by this kind of stuff anymore, but then Jonathan Hickman got them doing some googling when he put this dialogue in *House of X*:
[](https://i.stack.imgur.com/mGS72.jpg)
Notice the term **Heller-Faust line**. I am a computer scientist. A.I. is not my area, but I know enough about it to usually detect disinformation or bullshit when I hear laypeople talking about it. But I had to look that one up, even phone a colleague to know if that was a real thing!
---
The point being that you don't have to be accurate. You can pull a term from a body cavity and still make it work. Without hitting search engines anymore, I thought of a few more terms that you could use:
* **Autopyrolysis** (actually means "self-breaking through fire or high temperature")
* **Phoenixalia**
* **Mors Ignea** ("fiery death"). By the way I totally need to assemble a metal band with this name now.
* **Fogosa** (just means "hot girl" in my latin-based native language, but your audience might never find out)
[Answer]
Try **Tachypyrolysis**
From the Greek "tach-" (rapid), "pyro-" (fire), and "-lysis" (separating). The prefix "tachy-" is already well known in the medical realm (as in tachycardia or tachyphylaxis). "Pyrolysis" is itself a [common term](https://en.wikipedia.org/wiki/Pyrolysis) in the chemistry community, where it describes the thermal decomposition of a material at a high temperature.
Who knows, maybe in the future the medical community got tired of Latin/Greek and started using Esperanto instead. If that happened, you could use a term like **Netakorpofaj** (from neta≈≠ga "inappropriate", korpo "body", fajro "fire"). Call it "NKF" for short. The implication that there exists an *appropriate* body fire is merely a coincidence.
[Answer]
If you want to name something in a realistic sounding way, you should think about how this name came to be.
The first question is who named it? If something was named by a scientific organisation, the name would be done in a very specific way. Diseases are very often named by the first patient. This does not mean the first person in history who ever got the disease, it's the first patient who's case was properly described in medical literature. As this is more of an affect, and not a real medical condition the actual combustion would most likely be John Doe's Syndrome. Sometimes instead of the patient, the doctor describing the disease uses his own name, but the effect is the same.
If this was described more in a lab than in the field, without a real person involved the name could be Latin. It could also just be an acronym for normal English words. SPH could be common. There could also be two name, one for the condition that leads to the gas buildup, and the other for the actual combustion, similar to HIV and AIDS.
The name could also come from more colloquial sources. In this case the name could be simpler. Depending on the source something this could be anything from SPH to Go-Boom-Disease. Think about how reached the media and made this name popular. A real world example would be Swine Flue.
[Answer]
Autogenic thoracic sarcopyrrosis (ATS)? I've mixed Greek and Latin, I think, but that ought to translate as something like 'self-generating chest flesh-fire'.
[Answer]
What about the [Wick Effect](https://en.wikipedia.org/wiki/Wick_effect) which is theorized to be the cause of many real life reported SHC events. Basically after ingintion, the human body is kept aflame due to melting fat continuing to fuel the fire, and several cases of unexplained burning of a human body are thought to be caused by an accidental igition of clothing that burns and soaks in melting body fat until most of the body is burned away (With only the feet and occasionally hands being the only parts of the body to remain due to both parts having very low body fat compared to the rest of the body.
The typical ignition source is usually a cigarette and typical victims are elderly or otherwise exhibit a low mobility as the process is slow to start and consume the body.
[Answer]
Idiopathic thermal decomposition. “Idiopathic” is a medical term meaning “of unknown origin” and adds a touch of real medical terminology. Or, perhaps, idiopathic pyrolysis, though “pyrolysis “ has a meaning that doesn’t quite match (burning in an inert atmosphere).
[Answer]
Either "Edith Syndrome" or "Ado Syndrome", based on the name of Lot's wife from Judeo-Christian tradition. In that tradition, she turns back to view the destruction of Sodom and Gomorrah, resulting in her being turned into a pillar of salt.
If the combustion converts the victim's body into a pillar of ash, with charred flesh still attached to an intact blackened skeleton, then the parallel to the ancient story might be justified.
Alternatively, to get closer to the ashy remains of the combustion victims, you might call it "Pompaeii Syndrome" based on the compacted ash human simulacrums which were found at the base of Mt. Vesuvius.
[Answer]
Medical terms usually come from Latin or Greek (see <https://www.youtube.com/watch?v=oCCY1LuE2-k>). So, a good way to make up the name of a condition is to just concatenate latin/greek words at random... kinda.
*Endo* means "from the inside".
[*Thermolysis*](https://en.wikipedia.org/wiki/Thermal_decomposition) is a rapid chemical reaction caused by heat that ruptures molecules (from Greek *therme*- (heat) and -*lysis* (to unbind))
**Fwoosh!** Endothermolysis: a rapid internal chemical reaction caused by heat. You can replace "thermo" with "pyro" (fire) to make it more explicitly related to fire. Also it sounds cooler.
**Endopyrolysis.**
[Answer]
What's wrong with the actual medical & scientific terms already in use for this anecdotal phenomenon?
* spontaneous human combustion
* preternatural combustion
* spontaneous combustion
All these terms show up in various Good Sources (Jstor, Lancet, NIH, etc)
[Answer]
For what you are describing, probably severe sodium poisoning. Here's a material data sheet <https://cdn2.lasecsa.co.za/pdf/sds/Sodium%20Metal.pdf>
Short version : light metals - sodium, lithium react with water to produce hydrogen gas, oxygen gas, and enough heat to self-ignite. When I was younger, it was a cool chemistry demonstration to throw pieces of metallic sodium into a pond and watch them explode.
Because it is so reactive, light metals in metallic form are usually encased in some kind of material that keeps water off - oil being common. Cellophane gelcaps loaded with a mineral oil and metallic sodium grains might do the same thing and allow ingestion.
[Answer]
This answer is in part a frame challenge.
"Spontaneous Human Combustion" has been scientifically shown to be no such thing.
It is a characteristic of fatty meats that if they are wrapped in cloth, which is then set alight in an enclosed area with a low rate of oxygen ingress that they smoulder, the fat melting and burning on the surface of the cloth like wax rising up a candle wick. In fact, this can lead to an otherwise non-flammable substance being able to burn.
This can be demonstrated fairly readily with an uncooked leg of pork and some woolen cloth. Wrap the pork in the wool, then light it in an enclosed space. The fat melts, and wicks through the wool where it burns.
Historical cases of SHC have in fact been cases where the victim has died at around the time that the fire starts - often from some source of ignition that a healthy, living person would reflexively avoid, like a cigarette, a heater or a cooker. However, being very ill or recently deceased, the "victim" is unable to move away or extinguish the fire, and if still alive when set alight, they die from the trauma shortly thereafter.
There have been recorded cases exactly like the OP's, where a person enters a room to see a flame suddenly erupt from the victim. This has been attributed to the fact that the victim merely smoulders when in a closed, oxygen-deprived room, but when the witness opens the door and enters, there is a sudden rush of oxygenated air into the room, which causes the smouldering fire to flare up in just that manner.
So... in such a case, a coroner might conclude that the victim met their fate as a result of some non-fire-related reason, or perhaps was incapacitated by some other cause, which enabled their clothed body to be set alight, causing their death.
The technical term applied to the case would therefore *not* be a medical term at all, but a fireman's description: a smouldering fire enabled by the wick effect, occurring in an enclosed, unventilated space, which upon the door being opened and admitting fresh, oxygenated air, caused the slow-burning oxygen-starved fire to flare up and burn more rapidly.
Any movement that might be attributed to the death of a living person at that specific moment where the smouldering flame flares up might be more accurately attributed to the suddenly increased heat of combustion causing post-mortem tissue contraction, movements and even vocalizations.
Any medical terminology used would be to describe (if there were sufficient remains to successfully autopsy) the cause of death or the cause of sufficient incapacity so that the victim could be unable to react to being burned sufficiently to avoid their death.
This could be any of a great many causes, from heart attack to a drug overdose, and is beyond the scope of this question.
The OP need not invent any implausible internal source of combustion unless future advances in technology enable a person to be poisoned in such a way that enables true spontaneous combustion from within.
[Answer]
If you want to describe the effects of SHC in a medical sounding way, you might consider a term like ***pernicious exothermia*** and let the reader do a 2+2
[Answer]
I'm thinking something along the lines of Exanthropyromortis?
Ex - outward (as in explosion)
Anthro - Human (as in anthropology)
Pyro - Fire
Mortis - Death.
Or on the same lines but in two words Exanthropic Pyromortis (exanthropic as in used to be a human .... )
(sorry that's really grim)
[Answer]
There is no 'scientific' term for Spontaneous Human Combustion, as it is not a real condition.
The best advice I can give you is to use your creativity to create a term that fits your book best. 1. Look for synonyms.
- Write twenty-five of your favorites in a list.
- Combine them to make a term that fits the style of your story best.
[Answer]
**R**apid **O**nset **U**nexpected **S**parkler **S**yndrome.
Bonus *The Princess Bride* reference gratis.
[Answer]
In our cells, we mammals, and I am assuming we are all mammals reading this, oxidize glucose to provide the energy needed to live.
Certainly, the topic of cellular metabolic chemistry is vastly complicated and any attempts of mine at explanation would be, by very definition, overly simplistic, base and unseemly sketches of cosmic beauty. But, crudely put, glucose is sugar and oxidation is combustion. Normally well regulated and self-limiting, producing just enough ATP, the true fuel of our cellular scale lives, that our cells may carry out the million tiny miracles for which they are responsible.
Since the oxidation is exothermic, if it became, momentarily, less well regulated, because of confusion in mitochondrial and glycolytic pathway communications, then it might be termed Runaway Glucose Oxidosis or Catastrophic Glucose Reduction or Glucose Reduction Avalanche.
Note: Reduction is used in the chemistry sense of the word, *a chemical reaction that involves the gaining of electrons by one of the atoms involved in the reaction between two chemicals. The term refers to the element that accepts electrons, as the oxidation state of the element that gains electrons are lowered.* This was not an attempt to be more accurate but because oxidation is a harsh jagged word and reduction is nicer, rhymes with seduction and subduction.
[Answer]
I kind of like the sound of "self-ignatory flatulence". I mean, just imagine the conversation:
```
Doctor: I'm sorry, Mrs. Jones, but your husband is gone.
Mrs Jones: Gone?!? What do you mean, "gone"?!?!?
Doctor: I'm very sorry, Mrs. Jones. There was nothing we could do.
Mrs. J: But...but...but...
Doc: If it means anything, it was very quick. He never felt a thing, I'm sure.
Mrs. J: But...just this morning...he sat down like he always does, and he asked me to
make him breakfast, just like I always do. He had eggs, and beans, and refried
beans, and roasted beans, and canned beans, and chili with beans, and black
beans, and navy beans, and pinto beans, and beans-beans-beans-beans-beans!
Beans, beans, and more beans! That man *loved* his beans! And now, he's
GONE!!!! By the way, what did he die from?
Doc: Ummmm...self-ignatory flatulence.
Mrs. J: You mean...?
Doc: Yep. Death Farts.
Mrs. J: <swoons>
```
[Answer]
Egopyronova
Pyroscade
Egoexohypthermia
Lots of scientific therms are just going from the common denominator to the specific denominator in order from start to finnish.
Like Birds WithLongWings ThathaveSmallBeaks WithYellowTip - often added with a name of discoverer or location of discovery if that location makes it unique.
So Ego (Person) (Exo) (Exotherm reaction) (hyper) (Huge) thermia (Temperature) is basically a attempt to construct such a word based on the rules above.
] |
[Question]
[
Let us assume planet Earth, with a history similar to ours. Except, the result of the computer revolution is not a computer system based on binary (i.e. 0 and 1), but some other system. This system could be digital, with more than two digits, or otherwise.
Transistors were invented in this alternate timeline, in the 1950s. Any other technology that was invented can be shaped to favor a non-binary computing system.
**What is the minimal historical change that would make non-binary computers the standard in a world equivalent to our modern world?**
[Answer]
Non binary computers, in particular ternary computers, [have been built](https://en.wikipedia.org/wiki/Ternary_computer) in the past (emphasis mine).
>
> One early calculating machine, built by Thomas Fowler entirely from wood in 1840, operated in balanced ternary. The first modern, electronic ternary computer Setun was built in 1958 in the Soviet Union at the Moscow State University by Nikolay Brusentsov, and it had notable advantages over the binary computers which eventually replaced it, such as **lower electricity consumption and lower production cost**.
>
>
>
If you want to make ternary computer the standards, I think you should leverage on those advantages: make energy more expensive, so that saving energy is a big advantage, and make production more expensive.
Note that, since smelting silicon is an energy intensive activity, already increasing the cost of energy will indirectly affect the production costs.
[Answer]
Instead of avoiding it, **transcend binary:**
**Either** let the evolution of technology take its course and somehow create a demand for non-binary processors. Analogous to what is happening now in the crypto currency scene: The developers of [IOTA](https://iota.readme.io/docs/whitepaper) based their project on a ternary architecture model and are even working on a ternary processor (JINN).
**Or** let aggressive patenting and licensing in the early stages of binary processors (e.g. a general patent for binary processors due to lobbying or misjudgements in the patent office) be the cause for starting work on non-binary processors with less restrictive and more collaborative patents.
Patentability requirements are: novelty, usefulness, and non-obviousness[1](https://en.wikipedia.org/wiki/Patent).
>
> [the] nonobviousness principle asks whether the invention is an
> adequate distance beyond or above the state of the art[2](https://en.wikipedia.org/wiki/Inventive_step_and_non-obviousness)
>
>
>
So this could be used to have a patent granted on binary processors. And even if it was an illegitimate patent, that would be revoked in future lawsuits, this situation could give rise to non-binary processors.
[Answer]
**I would like to advance the idea of an [analog computer](https://en.wikipedia.org/wiki/Analog_computer).**
Analog computers are something like the holy grail of electronics. They have the potential of nearly infinite more computing power, limited only by the voltgae or current measuring discriminator (i.e., the precision of measuring an electric state or condition).
The reason we don't have them is because using transistors in their switching mode is *simple.* Simple, simple, simple. So simple, that defaulting everything to the lowest common denominator (binary, single-variable logic) was obvious.
But even today, change is coming.
>
> Analog computing, which was the predominant form of high-performance computing well into the 1970s, has largely been forgotten since today's stored program digital computers took over. But the time is ripe to change this. ([Source](https://blog.degruyter.com/algorithms-suck-analog-computers-future/))
>
>
>
>
> If analog and hybrid computers were so valuable half a century ago, why did they disappear, leaving almost no trace? The reasons had to do with the limitations of 1970s technology: Essentially, they were too hard to design, build, operate, and maintain. But analog computers and digital-analog hybrids built with today’s technology wouldn’t suffer the same shortcomings, which is why significant work is now going on in analog computing in the context of machine learning, machine intelligence, and biomimetic circuits.
>
>
> ...
>
>
> They were complex, quirky machines, requiring specially trained personnel to understand and run them—a fact that played a role in their demise.
>
>
> Another factor in their downfall was that by the 1960s digital computers were making large strides, thanks to their many advantages: straightforward programmability, algorithmic operation, ease of storage, high precision, and an ability to handle problems of any size, given enough time. ([Source](https://spectrum.ieee.org/computing/hardware/not-your-fathers-analog-computer))
>
>
>
But, how to get there without getting hung up on the digital world?
* A breakthrough in discrimination. Transistors, for all their value, are only as good as their manufacturing process. The more precisely constructed the transistor, the more precise the voltage measurement can be. The more precise the voltage measurement, the greater the programatic value of a change in voltage = faster computing and (best of all for most space applications) faster reaction to the environment.
* Breakthrough in modeling equations. Digital computers are, by comparison, trivial to program (hence, BASIC). Their inefficiency is irrelevant compared to their ease of use. However, this is because double-integration is a whomping difficult thing to do on paper, much less to describe such that a machine can process it. But, what if we could have languages like [Wolfram](https://www.wolfram.com/language/), [R](https://www.r-project.org/), or [Haskell](https://www.haskell.org/) without having to go through the digital revolution of BASIC, PASCAL, FORTRAN, and C first? Our view of programming is very much based on how we perceive (or are influenced by) the nature of computation. Had someone come up with an efficient and flexible mathematical language before the discovery of switching transistors... the world would have changed forever.
***Would this entirely remove digital from the picture?***
Heck, no. That's like saying the development of a practical Lamborghini (if the word *practical* can ever be applied to a Lamborghini) before, say, the Edsel would mean we would have never seen the Datsun B210. The single biggest weakness of analog computing is the human-to-machine interface. The ability to compute in real time rather than through a series of discrete often barely related steps is how our brains work — but that doesn't translate well to telling a machine how to do its job. The odds are good that a hybrid machine (digital interface to an analog core) would be the final solution (as it will today). Is this germain to your question? Not particularly.
**Conclusion**
Two breakthroughs: one in transistor manufacture and the other in symbolic programming, are all that would be needed to advance analog computation with all of its limitless computational power over digital computing.
[Answer]
Having thought about this and looked at L.Dutch's answer, I may withdraw my original answer (or leave it just for interest).
Instead I will give a political answer.
As mentioned by L.Dutch, the Soviets came up with a ternary system (see below). Because of the limited use of the Russian language throughout the world the Soviets often resented the fact that US scientific papers got more credence - after all English is the Lingua Franca of science. (This is true by the way, not a fiction, I'll look for references).
Suppose the Russians had won a war over the West. It was common in Soviet Russia for science to be heavily politicised (again I'll look for references). Therefore, regardless of the validity of a non-binary system the Russians could have mandated ternary or some other base simply as a form of triumphalism.
Note - I'm chickening out of finding references at the moment. I've found some but they involve delving into Marxist doctrine or buying an expensive book. My personal knowledge of the situation came from talking to a British scientist who was digging through old Russian papers looking for bits that had been missed or had been distorted by doctrine. Maybe I'll delve further but not right now.
---
>
> The first modern, electronic ternary computer Setun was built in 1958
> in the Soviet Union at the Moscow State University by Nikolay
> Brusentsov
>
>
> <https://en.wikipedia.org/wiki/Ternary_computer>
>
>
>
[Answer]
A ternary system would be preferred in a world where data storage cost exceeds all other cost considerations in computers. This preference would be due to **[radix economy](https://en.wikipedia.org/wiki/Radix_economy)**, which essentially quantifies the relative cost of storing numbers in a particular numbering system. Euler's number *e ≈ 2.718* has the lowest radix economy. Among integers, 3 has the lowest radix economy, lower than 2 and 4 (which have the same).
If the first storage medium used for computing would have stored ternary digits for less or just slightly more cost than binary digits, and if processing cost would have been insignificant compared to storage cost, ternary computing might have become the dominant standard. The advantage of ternary systems is small (around 5 percent), but could be important if storage cost was a serious consideration.
Binary computers dominate today mostly because electricity was the first effective medium to store and process numbers, and a single threshold voltage to distinguish between two states is easier to manage than two or more thresholds for three or more states.
Build your transistors in a medium that can store and process ternary digits efficiently, and emphasize on the high cost of storing. A mechanical example would be a switch that can take three positions in a triangle.
[Answer]
[Toolforger](https://worldbuilding.stackexchange.com/a/131355/37815) has one thing right: Binary computers *are* the most efficient computing devices possible. Period. Ternary has no *technological* advantage, whatsoever.
However, I'm going to give a suggestion of how you can offset the disadvantage of ternary computing, to allow your society to actually use ternary computers instead of binary ones:
**Your society has evolved to use a *balanced* numeral system.**
Balanced numeral systems don't just use positive digits like we do, they use an equal number of *negative* and positive digits. As such, [balanced ternary](https://en.wikipedia.org/wiki/Balanced_ternary) uses three digits for -1, 0, and 1 instead of the unbalanced 0, 1, and 2. This has several beneficial consequences:
* Balanced numeral systems have symmetries that unbalanced systems lack. Not only can you exploit commutativity when doing calculations (you know what 2+3 is, so you know what 3+2 is), but also symmetries based on sign: -3-2 = -(3+2), -3\*2 = 3\*-2, -3\*-2 = 3\*2, and 3\*-2 = -(3\*2).
* You have more computations with trivial outcome: x+(-x) = 0 and -1\*x = -x.
* The effect is, that you have much *less* to learn when learning balanced numeral systems. For instance, unbalanced decimal requires you to learn 81 data points by heart to perform all the four basic computations, whereas balanced nonal (9 digits from -4 to 4) requires only 31 data points, of which only 6 are for multiplication. The right-most column uses `-4 = d, -3 = c, -2 = b, and -1 = a as negative digits:
```
2*2 = 0*9 +4 = 4
2*3 = 1*9 -3 = 1c
2*4 = 1*9 -1 = 1a
3*3 = 1*9 +0 = 10
3*4 = 1*9 +3 = 13
4*4 = 2*9 -2 = 2b
```
The entire rest is either trivial or follows from symmetries. *That's all the multiplication table your school kids need to learn!*
* Because you can get both positive and negative carries, you get much less and smaller carries in long additions. They simply tend to cancel each other out.
* Because you have negative digits as well as positive ones, negative numbers are just an integral part of the system. In decimal, you have to decide which number is greater when doing a subtraction, then subtract the smaller number from the larger one, then reattach a sign to the result based on which of the two numbers was greater. In balanced systems *you don't care* which number is greater, you just do the subtraction. Then you look at the result and see whether it's positive or negative...
As a matter of fact, I once learned to use balanced nonal just for fun, and in general, it's indeed much easier to use than decimal.
My point is: To anyone who has been brought up calculating in a balanced numeral system, an unbalanced system would just feel so unimaginable awkward and cumbersome that they will basically think that ternary is the smallest base you can use. Because binary lacks the negative digits, how are you supposed to compute with that? What do you do when you subtract 5 from 2? You absolutely need a -1 for that!
As such, a society of people with a balanced numeral system background may conceivably settle on balanced ternary computers instead of binary ones. And once a chunk of nine balanced ternary digits has been generally accepted as the smallest unit of information exchange, no one will want to use 15 bits (what an awkward number!) to transmit the same amount of information in a binary fashion, with all the losses that would imply.
The result is basically a lock-in effect to balanced ternary that would keep people from using binary hardware.
---
### Aside: Unbalanced decimal vs. balanced nonal
Here is a more detailed comparison between decimal and balanced nonal. I'm using `a, b, c, d` as the negative digits `-1, -2, -3, -4` here, respectively:
* Negation
Here the learing effort for decimal is zero. For balanced nonal, you have to learn the following table with nine entries:
```
| d c b a 0 1 2 3 4
--------+------------------
inverse | 4 3 2 1 0 a b c d
```
* Addition
Decimal has the following addition table, the right table show the 45 entries that need to be learned:
```
+ | 0 1 2 3 4 5 6 7 8 9 + | 0 1 2 3 4 5 6 7 8 9
--+----------------------------- --+-----------------------------
0 | 0 1 2 3 4 5 6 7 8 9 0 |
1 | 1 2 3 4 5 6 7 8 9 10 1 | 2
2 | 2 3 4 5 6 7 8 9 10 11 2 | 3 4
3 | 3 4 5 6 7 8 9 10 11 12 3 | 4 5 6
4 | 4 5 6 7 8 9 10 11 12 13 4 | 5 6 7 8
5 | 5 6 7 8 9 10 11 12 13 14 5 | 6 7 8 9 10
6 | 6 7 8 9 10 11 12 13 14 15 6 | 7 8 9 10 11 12
7 | 7 8 9 10 11 12 13 14 15 16 7 | 8 9 10 11 12 13 14
8 | 8 9 10 11 12 13 14 15 16 17 8 | 9 10 11 12 13 14 15 16
9 | 9 10 11 12 13 14 15 16 17 18 9 | 10 11 12 13 14 15 16 17 18
```
The same table for balanced nonal only has 16 entries that need to be learned:
```
+ | d c b a 0 1 2 3 4 + | d c b a 0 1 2 3 4
--+-------------------------- --+--------------------------
d |a1 a2 a3 a4 d c b a 0 d |
c |a2 a3 a4 d c b a 0 1 c |
b |a3 a4 d c b a 0 1 2 b |
a |a4 d c b a 0 1 2 3 a |
0 | d c b a 0 1 2 3 4 0 |
1 | c b a 0 1 2 3 4 1d 1 | 2
2 | b a 0 1 2 3 4 1d 1c 2 | 1 3 4
3 | a 0 1 2 3 4 1d 1c 1b 3 | 1 2 4 1d 1c
4 | 0 1 2 3 4 1d 1c 1b 1a 4 | 1 2 3 1d 1c 1b 1a
```
Note the missing diagonal of zeros (a number plus its inverse is zero), and the missing upper left half (the sum of two numbers is the inverse of the sum of the inverse numbers).
For instance, to calculate `b + d`, you can easily derive the result as `b + d = inv(2 + 4) = inv(1c) = a3`.
* Multiplication
In decimal, you have to perform quite a bit of tough learning:
```
* | 0 1 2 3 4 5 6 7 8 9 * | 0 1 2 3 4 5 6 7 8 9
--+----------------------------- --+-----------------------------
0 | 0 0 0 0 0 0 0 0 0 0 0 |
1 | 0 1 2 3 4 5 6 7 8 9 1 |
2 | 0 2 4 6 8 10 12 14 16 18 2 | 4
3 | 0 3 6 9 12 15 18 21 24 27 3 | 6 9
4 | 0 4 8 12 16 20 24 28 32 36 4 | 8 12 16
5 | 0 5 10 15 20 25 30 35 40 45 5 | 10 15 20 25
6 | 0 6 12 18 24 30 36 42 48 54 6 | 12 18 24 30 36
7 | 0 7 14 21 28 35 42 49 56 63 7 | 14 21 28 35 42 49
8 | 0 8 16 24 32 40 48 56 64 72 8 | 16 24 32 40 48 56 64
9 | 0 9 18 27 36 45 54 63 72 81 9 | 18 27 36 45 54 63 72 81
```
But in balanced nonal, the table on the right is reduced heavily: The three quadrants on the lower left, the upper right and the upper left all follow from the lower right one via symmetry.
```
* | d c b a 0 1 2 3 4 * | d c b a 0 1 2 3 4
--+-------------------------- --+--------------------------
d |2b 13 1a 4 0 d a1 ac b2 d |
c |13 10 1c 3 0 c a3 a0 ac c |
b |1a 1c 4 2 0 b d a3 a1 b |
a | 4 3 2 1 0 a b c d a |
0 | 0 0 0 0 0 0 0 0 0 0 |
1 | d c b a 0 1 2 3 4 1 |
2 |a1 a3 d b 0 2 4 1c 1a 2 | 4
3 |ac a0 a3 c 0 3 1c 10 13 3 | 1c 10
4 |b2 ac a1 d 0 4 1a 13 2b 4 | 1a 13 2b
```
For instance, to calculate `c*d`, you can just do `c*d = 3*4 = 13`. Or for `2*b`, you derive `2*b = inv(2*2) = inv(4) = d`. It's really a piece of cake, once you are used to it.
Taking this all together, you need to learn
* for decimal:
0 inversions
45 summations
36 multiplications
**Total: 81**
* for balanced nonal:
9 inversions
16 summations
6 multiplications
**Total: 31**
[Answer]
# [Base-4](https://en.wikipedia.org/wiki/Quaternary_numeral_system)
This might be a natural choice for a society that perfected digital *communication* before digital *computation*.
Digital signals are often transmitted (i.e., “passed through the analogue world”) using [quadrature phase-shift keying](https://en.wikipedia.org/wiki/Phase-shift_keying#Quadrature_phase-shift_keying_(QPSK)), a special form of [quadrature amplitude modulation](https://en.wikipedia.org/wiki/Quadrature_amplitude_modulation). This is generally more performant and reliable than simple amplitude modulation, and more efficient than frequency modulation.
QPSK / QAM by default use four different states, or a multiple of four, as the fundamental unit of information. We usually interpret this as “it always transmits two bits at a time”, but if this method were to be standard before binary computers, we'd probably be used to measure information in quats (?) rather than bits.
Ultimately, the computers would at the lowest level probably end up looking a lot like our binary ones, but with usually two bits paired together to a fundamental “4-logical unit”. Unlike [binary-coded decimal](https://en.wikipedia.org/wiki/Binary-coded_decimal), this doesn't incur any overhead of unused binary states.
And it could actually make sense to QPSK-encode even the local communication between processor and memory etc. – wireless transmission everywhere!, thus making the components “base-4 for all that can be seen”.
[Answer]
Get rid of [George Boole](https://en.wikipedia.org/wiki/George_Boole), inventor of Boolean Algebra, probably the main mathematical foundation of computer logic.
Without Boolean Algebra, regular algebra would give quite an edge to decimal computers, even if you needed three to four times as much hardware per digit.
There's no need to kill him, just have something happen that stops his research or get him interested in another field instead.
[Answer]
It's almost completely irrelevant.
The binary nature of computers is very very *very* rarely relevant in practice. Just about the only practical situation where the binary nature of computers is relevant is when doing sophisticated error bounds analysis of floating point calculations.
In actual reality, there are quite a few aspects of modern computing which do not even rely on binary representations. For example, we all like SSDs, don't we? Well, modern cheap consumer SSDs are not binary devices — they use [multi-level cells](https://en.wikipedia.org/wiki/Multi-level_cell) as their fundamental building blocks. For another example, we all like Gigabit Ethernet, don't we? Well, the unit of transmission in Gigabit Ethernet is an indivisible 8-bit octet (transmitted as a 10-bit symbol, but hey, who counts).
No modern computer (all right, hardly any modern computer) can access one bit of storage individually. Most usually, the smallest accessible unit is an octet of eight bits, which can be seen as an indivisible atom with 256 possible values. (And even this is not really true; what exactly is the atomic unit of memory access varies from architecture to architecture. Access to one individual bit is not atomic on any computer I know of.)
Donald Knuth's [*Art of Computer Programming*](https://en.wikipedia.org/wiki/The_Art_of_Computer_Programming), which the closest thing we have to a fundamental text in informatics, famously uses the fictional MIX computer for practical examples — and one of the charming characteristics of MIX is that *one does not know* whether it's a binary or a decimal computer.
What actually matters is that modern computers are digital — in the computer, everything is a number. That the numbers in question are represented by tuples of octets is a detail which very rarely has any practical or even theoretical importance.
[Answer]
EDIT - On reading the answer by L.Dutch, I see that there is an energy-saving argument for using trinary. I'd be interested to find out how theoretically true that is. Crucially the OP talks about transistors rather than thermionic valves and that could make a difference. There are also other energy questions to address other than the simple switching of a transistor. It would be good to know the extent of this saving and any extra cost associated with building and maintaining the hardware. Heat dissipation may also be an issue.
I remain open-minded as well as interested in this approach.
---
I don't think there is a historical justification for your premise as far as transistors are concerned so instead, I will just say:
The minimum historical change is **No Electronics**
It's possible to use other bases but just a really bad idea.
**IBM 1620 Model I, Level H**
>
> IBM 1620 data processing machine with IBM 1627 plotter, on display at
> the 1962 Seattle World's Fair The IBM 1620 was announced by IBM on
> October 21, 1959,[1] and marketed as an inexpensive "scientific
> computer".[2] After a total production of about two thousand machines,
> it was withdrawn on November 19, 1970. Modified versions of the 1620
> were used as the CPU of the IBM 1710 and IBM 1720 Industrial Process
> Control Systems (making it the first digital computer considered
> reliable enough for real-time process control of factory
> equipment)[citation needed].
>
>
> Being variable word length **decimal**, as opposed to
> fixed-word-length pure binary, made it an especially attractive first
> computer to learn on – and hundreds of thousands of students had their
> first experiences with a computer on the IBM 1620.
>
>
> <https://en.wikipedia.org/wiki/IBM_1620>
>
>
>
The key phrase there is *variable word length decimal* which is a real faff and actually still uses binary at the electronic level.
**Reasoning**
Any other electronic system than binary will soon evolve into binary because it depends on digital electronics.
It is commonly supposed, by those not in the know, that zero voltage represent a binary zero and some arbitrary voltage, e.g. 5 volts, represents a 1. However in the real world these voltages are never so precise. It is much easier to have two *ranges* with a specified changeover point.
Having to maintain say ten different voltages for ten different digits would be incredibly expensive to make, unreliable and not worth the effort.
So your minimum historical change is **No Electronics**.
[Answer]
As I understand it, early tribes used base 12 and it's a lot more flexible than 10--they had a way to count to 12 by counting knuckles to get up to 60 on two hands pretty easily which is the basis of our "Degrees".
10-finger-counters supposedly defeated the base 12ers but kept their time system and degree-based trigonometry.
If the base 12ers had won, a three-state computer might have made a LOT more sense (Binary might have actually looked silly). In this case A byte would probably be 8 tri-state bits (let's call it 8/3) which would perfectly fit 2 base-12 digits instead of our 8/2 layout which always had a bit of a mis-match.
We tried to cope with our mismatch by using BCD and throwing away 6 states from each nibble (1/2 byte) for a more close approximation of base 10 which gave us a "Pure" math without all these weird binary oddities you get (like how in base 10, 1 byte holds 256 states, 2 bytes hold 65536, etc)
With 3/8, base 12ers would have no mismatch, it would be really clean. Round 3-bit numbers would often look like nice base12 numbers: 1 byte would hold 100 states, and 2 bytes would hold 10000, etc.
So can you change the numeric base of your book? Shouldn't come up too often :) It would be fun to even number pages in base 12... complete submersion.
[Answer]
Decimal computers.
Modern computers are, indeed, binary. Binary is the classification of an electrical signal as occupying one of two states, conditional on the voltage. For the sake of simplicity, you could say that in a 5V system, anything signal above 4V is a '1' and everything else is a '0'. Once a signal has been confined to two states, it's pretty easy to apply Boolean math, which was already well-explored ahead of computers. Binary was an easy choice for computers because so much work was already done in the area of Boolean algebra.
When we needed to increase the range of numbers, we added more signals. Two signals (two bits) could represent 4 distinct values. 3 bits - 8 values, and so-on. But what if, instead of adding more signals to expand our values, we simply divided the existing signals up more. In a 5V system, one signal could represent a number from 1-10 if we divide up the voltage. 0-0.25 volts = 0. 0.25-0.50 volts = 1. 0.50-0.75 volts = 2, etc. In theory, each signal would carry 5x the data a binary signal could. But why stop there? Why not split each signal into 100 distinct values?
Well, for the same reason we never went further than binary - environmental interference and lack of precision components. You need to be able to precisely measure the voltages to determine the value, and if those voltages change, your system becomes unreliable. All types of factors can affect electrical voltages, RF, temperature, humidity, metal density, etc. As components age, their tolerances tend to decrease.
Any number of things could have changed this - if you use a different medium - light, for example, interference isn't a concern. This is exactly why fiber-optics can carry so much more data than electrical connections.
The discovery of a room-temperature superconductor could also have allowed different computers to become standard. A superconductor doesn't lose electrons to heat. This means you could pump more voltage through a system without fear of overheating, requiring less precise components and less (no) cooling.
So, in-short, binary computers dominate because of physical limitations related to electricity and the the wealth of knowledge (Boolean Algebra) that was already available when vacuum tubes, transistors, and semiconductors came about. Change any of those factors, and binary computers may never have been.
[Answer]
In the late 1950s analog computers were developed using a hydraulic technology called fluidics. Fluidic processing is still used in automatic transmissions, although newer designs are hybrid electronic/fluidic systems.
[Answer]
**Hypercomputation**
According to [Wikipedia](https://en.wikipedia.org/wiki/Hypercomputation) Hypercomputation is defined to be the following:
>
> Hypercomputation or super-Turing computation refers to models of computation that can provide outputs that are not Turing computable. For example, a machine that could solve the halting problem would be a hypercomputer; so too would one that can correctly evaluate every statement in Peano arithmetic.
>
>
> The Church–Turing thesis states that any "effectively computable" function that can be computed by a mathematician with a pen and paper using a finite set of simple algorithms, can be computed by a Turing machine. Hypercomputers compute functions that a Turing machine cannot and which are, hence, not effectively computable in the Church–Turing sense.
>
>
> Technically the output of a random Turing machine is uncomputable; however, most hypercomputing literature focuses instead on the computation of useful, rather than random, uncomputable functions.
>
>
>
What this means is that Hypercomputation can do things computers cannot do. Not in terms of scope limitations such as the ability to access things on a network but rather what can and cannot be fundamentally solved as a mathematical problem.
Consider this. Can a computer store the square root of 2 and operate on it? Well maybe because it could store the coefficients of the polynomial whose solution is that square root and then index the solutions to that polynomial. Alright, so we can the represent so called algebraic numbers (at least I believe so). What about *all* real numbers? Euler's constant and pi are likely candidates for being unrepresentable in any meaningful sense using binary. We can approximate but we cannot have perfect representations. We could have pi be a special symbol as well as e and just increase the symbolic set. Still not good enough. That's the primary thing that hops to mind to me at least. The ability to digitally compute any real number with perfect precision.
This would be a reason for such a society to never discover binary computers being useful. At some point we switched from analog to binary because of electrical needs and signal stuff. I honestly do not know the details. We modeled the modern notion of processor and other things loosely off of the notion of a Turing Machine which was ultimately the form way of discussing computability which was kind of a multi faceted convergence of sorts. There was the idea of something being human computable and then theoretically computable. The rough abstract definition used for many years ended up converging with that of the notion of the Turing Machine. There was also the set theory concept of something or other (I don't recall the name) that ended up also converging to defining the same exact same concept of "computable". All of these converging basically meant it was said and done. That is what we as a society (or even as the human race for that matter) were able to come up with as a notion of what is and is not programmable. However, that is the convergence of possibly over 3000 years of mathematical development possibly beginning as far back in concept as Euclid when he formalized the most basic concepts of theorems and axioms. Sure math existed but it was just a tool. Nobody had a formal notion of it. Things are just obvious and known. If Hypercomputation is possible for humans to do (rather than it just being a thing limited to machines) then all it would take is one genius in the entire history of math to crack that. I'd say it is a reasonable thing for an alternate history.
[Answer]
Base-10 computing machines were used commercially to control the early telephone switching system. The telephone companies used them because they were solving a base-10 problem. As long as transistors remain larger and more expensive than mechanical relays, then there's no reason for telephone switchboards to switch to binary.
But that's cheating the spirit of the question. Suppose *cheap* transistors are invented. Then how can a civilization get out of binary computing? Binary logic is the best way to build a electronic deterministic computer with cheap transistors.
Answer: Analog neural networks outperform manually-programmed computers.
Humans are bad at programming computers directly. Manually-programmed computers can perform only simple unambiguous tasks. Statistical programming, also called "machine learning", can answer questions without clear mathematical answers. Machine learning can answer questions like "is this a picture of a frog". Hand-coding an algorithm to determine "is this a picture of a frog" is well beyond the capabilities of human beings. So are more complex tasks like "enforce security at this railroad station" and "take care of my grandmother in her old age".
Manually-programmed software outnumbers neural-network-based software right now, but that might plausibly be just a phase. Manually-programmed software is easier to create. In a few hundred years, neural-network-based software might outnumber manually-programmed so
One of the most promising methods avenues of machine learning involves neural networks, which uses ideas copied from biological brains. If we invent a good general-purpose AI then it might take the form of a neural network, especially if the AI is based off of the human brain.
If you're designing a computer to execute traditional programs then binary is the best way to go. But if the goal of a microchip is to simulate a human brain then it may be inefficient to build a binary computer and then simulate a human brain on it. It might make more sense to build a neural network into hardware directly. The human brain is an analog device, so a microchip based off of the human brain may be an analog device too.
If someone figured out how to build a powerful general-purpose AI as an analog neural network then chips optimized for neural networks may largely replace binary computers.
[Answer]
One simple change would be to make solid-state electronics impossible. Either your planet doesn't have abundant silicon, or there is some chemical issue which makes it uneconomic to manufacture semiconductors.
Instead, consider what would happen if Charles Babbage's mechanical computer designs (which were intrinsically decimal devices, just like the mechanical calculators which already existed in Babbage's day) were scaled down to nano-engineering size.
The earliest computers used vacuum tube electronics not semiconductors. The basic design of vacuum tube memory circuits was already known by 1920, long before the first computers, but for large scale computer memory tubes would have been prohibitively large, power-hungry, and unreliable. The earliest computers used various alternative systems - some of which were in effect mechanical, not electrical. So the notion of totally mechanical computers does have some relation to actual history.
[Answer]
**Morse code rules.**
[](https://i.stack.imgur.com/gtdYU.jpg)
<https://www.kaspersky.com/blog/telegraph-grandpa-of-internet/9034/>
Just as modern keyboards retain the QWERTY of the first typewriters, in your world the trinary code of Morse becomes the language of computers. Computers developed to rapidly send and receive messages naturally use this language to send messages other than written language, and then to communicate between parts of themselves.
There are apparently technical reasons making binary more efficient. <https://www.reddit.com/r/askscience/comments/hmy7w/if_morse_is_more_efficient_than_binary_why_dont/>
I am fairly certain that there would be more efficient setups than QWERTY as well, but now many decades since there was a need for keys to be spatially distant there is still QWERTY. So too Morse in your world. It was always the language of computers, and endures as such.
[Answer]
Oh, man. Although non-binary computers would be extremely inconvenient, I can easily imagine trinary, decimal or even analog computers becoming dominant, due to a terrible force all developers fear: entrenchment, and the need for legacy support. Lots of times in computing history, we've struggled with decisions made long ago, which we just couldn't break free of (for a long time) from sheer inertia. There's a lot of stuff even in modern processors which we never would have chosen, if it wasn't for the need to support existing software and architecture decisions.
So for your scenario, I imagine that for some reason one type of non-binary computer got a head start. Maybe for many years, computers didn't improve all that much due to some calamity. But software was still written for these weak computers, extremely useful and good software, tons of it. By the time things got going again, it was just much more profitable to focus on making trinary (or whatever) better, rather than trying to redo all the work Ninetel put into their 27-trit processor.
Sure, there are some weirdos claiming that binary is so much more sensible that it's worth it to make a processor that's BISC (binary instruction set circuit) in the bottom with a trinary emulation layer on top. But after the bankruptcy of Transbita, venture capital has mostly lost interest in these projects.
[Answer]
The creatures involved have three fingers, a ternary numeral system in everyday life, and the technical advantages of binary over ternary aren't as great as the advantages (radix economy, etc) of binary over decimal, so they never bothered to use a system other than the one they naturally knew innately?
[Answer]
They made quantum computing work much more quickly than we have.
Why have binary state, when you can have infinite?
They probably had binary computers for a short time, then cracked quantum.
>
> What is the minimal historical change that would make non-binary computers the standard in a world equivalent to our modern world?
>
>
>
Someone cracked a cheap room temperature way to make qbits
(ref: <https://medium.com/@jackkrupansky/the-greatest-challenges-for-quantum-computing-are-hardware-and-algorithms-c61061fa1210>)
[Answer]
**Politically enforced decimal base-10, expressed as binary-coded decimal**
The most reasonable alternative to the binary computer (which *is* the most efficient), would be a decimal base 10 one.
Suppose a government enforced computers to be decimal, since that system is most natural to humans. Perhaps they early on feared that computers would be restricted to an "elite" who understood binary and hex numbers, and wanted the technology to be accessible to everyone.
Same argument as why the computer mouse was invented and became a success: it wasn't because it was faster to use, and certainly not because it was ergonomic. But it was easier to use. Computer history repeats ease of use as an argument: Windows won and became the dominant OS, and so on.
---
A decimal computer could still be possible without changing the way computers work all that much - they would be using [binary-coded decimal](https://en.wikipedia.org/wiki/Binary-coded_decimal) (BCD). Processors would use different OP codes and data would be stored differently in memories. But otherwise, transistors will still remain on or off. Boolean logic will remain true or false.
Data would take up more space and calculations would be slower, but potentially it would be easier for humans to interpret raw data that way.
Take for example the decimal number 99. If you just know that binary for 9 is 1001, then you could write 99 with BCD as `1001 1001`. This is the way them nerdy binary watches work - they aren't actually using real binary base 2, but BCD, which is easier to read. Otherwise even the nerd would struggle to read the time.
To actually express the number 99 in raw binary base 2, it would be `110 0011`. Not nearly as readable for humans, though we saved one bit of data storage. To actually read this, a human will have to calculate it in decimal `64 + 32 + 0 + 0 + 0 + 2 + 1 = 99`.
[Answer]
Binary computers are simply the most efficient ones, claims to the contrary nonwithstanding (they are based on pretty exotic assumptions, the linked claim that "the future lies in analog computers" is even hilariously wrong though I can see where Ulmann comes from).
Binary computers are simply the most cost and space efficient option if the technology is based on transistors: A ternary computer would require more transistors than a binary one to store or process the same amount of information. The reason is that electrically, the distinction between "zero volts" and "five volts" is more like "anything below 2.0 volts" and "anything above 3.0 volts", which is much easier to control than ternary voltage levels such as "below 1.0 volts, between 2.0 and 3.0 volts, or between 4.0 and 5.0 volts". Yes you need the gaps between the voltage bands, because you need to deal with imprecisions due to noise (manufacturing spread and electric imprecisions); and yes the gaps are pretty large because the larger the gap, the more variance in the integrated circuits is inconsequential and the better is your yield (which is THE most important parameter of submicron manufacturing).
How to get around this?
Either change the driving parameters. In an economy where efficiency isn't even remotely relevant, you can choose convenience. Such an economy will instantly collapse as soon as it touches a more efficient one, so this requires either an isolated economy (Soviet-style or even North-Korea-style, though it requires some extra creativity to design a world economy where a massively less efficient economy isn't voted down on feet - historically this was enforced by oppressive regimes, it might be possible that the people stay at a lower level of income and goods for other reasons).
Or claim basic components that are better at being trinary than transistors. Somebody with a better background in microelectronics than me might be able to propose something that sounds credible, or maybe something that isn't based on classic electrical currents: quantum devices, maybe, or something photonic.
Why is this not done much in literature?
Because, ultimately, it does not matter much whether you have a bits or trits. Either way, you bunch together as many of them as you need to represent N decimal digits. Software engineers don't care much, unless they are the ones that write the basic algorithms for addition/subtraction/etc., or the ones that write the algorithms that needs to be fast (i.e. those that deal with large amounts of data, whether it's a huge list of addresses, or the pixels on the screen).
Some accidental numbers would likely change. Bunching 8 bits into a byte is helpful because 8 is a power of 2, that's why 256 (2^8) tends to pop up in the number of screen colors and various other occasions. With trinary computers, you'd likely use trytes, nine trits, giving 19683 values. HDR would be much later or not happen at all because RGB would already have more color nuances, so there would be some nonobvious differences.
You can simply make it a background fact, never highlight it, just to avoid the explanation.
Which begs the counter-question: What's the plot device you need trinary for?
[Answer]
[Cryptocurrency scammers](https://www.iota.org/) having convinced sufficiently many big corporations and governments to become partners in their pyramid scheme that economies of scale make their inefficient and ridiculous ternary-logic hardware cheaper than properly-designed computers.
[Answer]
My best bet is ternary optical where there is left true right true and off with left and right determined by polarization.
Ternary has -1 +1 and 0. If minus is false/off then zero is unknown. I think that's stupid. Ternary also has ridiculously huge and impractical truth tables.
By having left on and right off both be true, but having a different value one can get all the benefits of ternary without any of the drawbacks.
It still wouldn't make sense for an electronic computer. Having 1 voltage or 0 voltage is faster and more reliable then 0 1/2 or 1. That 1/2 can accidentally be seen as a 0 or a 1 which introduces errors.
No such issue when dealing with polarized light.
Perhaps if they were really good at optical fibers and microscopic polarized mirrors with a very efficient light source early on then using polarized optical ternary with 2 truth values of different meaning would have been used instead of electronics.
Perhaps a fear of EMPs would drive them to expedite their development of optical or maybe fluidic computers over electronics.
Fluidic computers can be made right now that can survive the temperatures and pressures of Venus surface. The absolute best electronics can't do that. Perhaps your alt history was more into space travel then ours was.
[Answer]
The first general programmable computer ENIAC was wired up to do its math in base 10 to make the debugging and human interface simpler. If its successor in alternate history ENIAC 2 stayed with that premise and subsequent generations never changed - computers would be base 10 at the machine language level.
In real history UNIVAC followed and went with the more natural binary.
<https://en.m.wikipedia.org/wiki/ENIAC>
<https://en.m.wikipedia.org/wiki/UNIVAC>
[Answer]
The strength of binary is that it's fundamentally a yes/no logic system, the weakness of binary is that it is fundamentally a yes/no logic system, you need multiple layers of logic to create "yes and" statements with binary logic. The smallest change you would need to make to change away from binary (in terms of having the rest of the world being the same but computing being different) would be to have the people who pioneered the science of computers, particularly Turing (thanks @Renan) aim for, and demand, more complex arrays of basic logic outcomes (a, b, c, etc... vary combinations, all of the above, none of the above). Complex outcome options require more complex inputs, more complex logic gates and a more complex programming language: consequently computers will be more expensive, more delicate, and harder to program.
A few people might mess around with binary for really basic machines, like pocket calculators, but true computers will be more complex machines.
] |
[Question]
[
My story is set in the early 1990s, and it's about various races of immortal humanoid mythical creatures living amongst humanity in secret. The main setting is a town in America that's been around for hundreds of years. It's one of various immortal "sanctuary towns" in the world, places populated exclusively by immortals and the humans in the know about them. While immortals frequently live in secret within human societies, sanctuary towns serve several purposes:
1: They provide immortals who can't pass for human with a place to live without having to spend their lives hiding in caves.
2: They provide immortal parents with a place to raise their children without their immortality raising massive eyebrows among humans wondering why that couple barely looks 10 years older than their teenage son.
3: They just generally allow immortals to openly be themselves without having to worry about anyone seeing them use their powers.
4: It allows the town to be built with immortal abilities and limitations in mind, such as, say, an underground network of tunnels connecting various buildings together so that the vampires who aren't strong enough to resist sunlight can get to certain places in town during the daytime.
This particular sanctuary town, located somewhere in the eastern United States, is run by the Drake Clan, a centuries-old alliance of vampires and werewolves, with other immortal species as minority members of the clan. I mention this because vampires and werewolves each have an ability that I suspect people might want to know about and factor into their answers: werewolves have superhuman senses of hearing and smell, and vampires have the ability to control the minds of any human they make eye contact with (as long as they aren't exposed to sunlight).
With that being established, here's the problem: in order for a sanctuary town to exist, it has to be able to prevent anyone who doesn't know the secret from getting into the town, because merely entering the town would likely cause you to become aware of the existence of immortals within minutes, if not by seeing one directly, then by hearing people casually talking about them. Sure, letting some people in (while temporarily covering up anything supernatural) will be inevitable, especially when the government is involved, but keeping this to a minimum is necessary in order for the town to serve its intended purpose. So the town has to have some kind of reasonable justification for why it's so selective about who is allowed in the town limits. Key word being "reasonable". They have to have a cover story that most people will buy without batting an eye at it.
**How does this sanctuary town contextualize the act of almost completely keeping outsiders out so that outsiders consider this completely normal?**
[Answer]
The answer to this is very simple: make the entire town into a gated community. Encircle the whole place with a fence and have guards on the gates who are or can pass for human. The guards would ask everyone approaching the gates for ID or other evidence of eligibility to enter, and would turn away anyone who didn't belong.
This can be achieved easily and legally by making the town private property. Being private property, anyone who enters without the permission of the owners or their representatives is trespassing.
The only complication might come if one of the residents is wanted by the state or federal authorities... but there are ways around this too. If the town is big enough, it could have its own police force, courthouse, tax office, OHSA department, and a branch of pretty much every other nosy government department on-site, manned by residents who will report whatever they need to report without adding irrelevant little details such as the fact that the person in question's membership in the human race is questionable at best. There could even be a privately run prison on-site, where the owners get to say which prisoners are kept in which area. Obviously the non-human prisoners would be kept seperate from the unknowing human inmates that might be foisted upon the facility.
The best defence that the town could have is to be populated by law-abiding taxpayers, and for anyone found breaking the law to be dealt with in the accepted manner on-site. Yes, people there might break the law, but they're arrested, charged and put on trial according to the law... with records to prove it.
On the rare occasions that a stranger must be allowed to enter, there could be a mechanism to warn the residents who cannot pass for human to get out of sight immediately... perhaps the street lights flicker in a particular pattern, there is an ultrasonic and/or subsonic tone, and/or some other cue that humans can't perceive or wouldn't recognise as being significant.
The concept of fortified cities has been around since ancient times, so it is no stretch of the imagination for this town to date back to the first days of the colonisation of the Americas by Europeans. As long as the town only remains physically apart from the rest of the country, but joins in politically - i.e. pays taxes and adopts the laws of the nation which controls the land on which it is located - there is no reason why it couldn't have existed since well before the USA became an independent nation.
Take the walled city of Carcassonne for example. It is thought to have existed as a fortified location since 100 BC, and for most of its existence, while the gates may have stood open, if undesirables came along - like strangers in armour and carrying weapons - the gates would have been closed to them.
[Answer]
# Salvator's Sanatorium for the Privileged Underprivileged.
Silly name for a Nut-house for the ultra rich.
**Cover story**: Everyone in the town is either a ~~delusionally insane~~ Eccentric millionaire, or one of their caregivers.
So **obviously** any visitor will encounter some very strange conversations, people taking about performing supernatural acts, etc.
The staff even cater to the whims of their eccentric patrons/patients, creating special effects to allow them to live out their fantasies. Want to lift a bus? Just mention it to your caretaker, she will arrange a hidden crane to do the heavy lifting!
Visitors are firmly reminded that it is impolite, indeed against county ordinance, to stare, point fingers, interrogate or otherwise belittle the inhabitants of this facility. They are also required to sign a non-disclosure agreement before entering town limits, as the privacy of the "guests" must be respected. No photography, etc.
After all, money makes majesty, and by that measure *all* of the inhabitants of this town are royalty.
P.S.
Because every person in the town is (supposedly) filthy rich, visitors get charged truly obscene priced for basic amenities. A 500 dollar hamburger and fries and a 8000 dollar hotel room will discourage visitors from loitering around and making a nuisance of themselves.
[Answer]
I think people are making this more complicated than it needs to be.
## Let the town sit at the end of the road.
~~Possibly in a nature reserve, like @EveryBitHelps suggests.~~
It should preferably be situated in the most boring combination of agricultural land and patches of nature that is at all possible. Make sure the local regulations on camping (with tents as well as with RV's) are strict, and that no official hotels, hostels etc exist in the area. I say *official*, as you will of course want visiting immortals to be able to find a place to stay, but these establishments are not in the phone book, don't pay taxes and overall just don't show up in the records.
Very few people would have a reason to go there to begin with, and no one would have a reason to stop there on their way somewhere else. I mean, under what circumstances would you go to a town without any famous sights, where you don't know anybody? This is before the internet, so it's easy to keep the amount of information that could draw outsiders to a minimum.
Now for the few that get the idea to go there there are measures:
**Put a roadblock on the only road there.** I imagine a construction site or something where a worker can come talk to the odd car that shows up to tell them that there will be slow going all the way there. The point is to deter all but the most intent. If someone insists on passing through, an alarm goes off in the town, and the visitor can be slowed down enough to give inhabitants plenty of time to adapt their appearance.
**Make sure the streets are laid out to keep outsiders in a certain area.** Put important stuff on main street. You may not have to completely evacuate the town every time some government official pays a scheduled visit to the town hall and has lunch at the one diner set up to look normal.
Optional: **Patrol the surrounding wilderness, and possibly put up a network of microphones or similar.** You don't want to be surprised by a hiker or a band of boy scouts. A job for a few werewolves?
If anyone finds everything out, that's a separate issue. If they cannot be controlled and need to disappear, the road to the town is a good place to arrange a car accident. It's well known to be dangerous stretch, which is also why local officials need to fix it up so often, which is a perfect cover for the construction sites mentioned above. If you can limit these disappearances to one every few years or so, that's probably enough to keep you off the radar.
I don't think it has to be much more complicated than that!
[Answer]
This is Clarks, LA.
[](https://i.stack.imgur.com/3jTEi.jpg)
Here's the wikipedia entry for Clarks.
<https://en.wikipedia.org/wiki/Clarks,_Louisiana>
Clarks, LA is the biggest town in Caldwell Parish - and exists on the main backroad (US-165) between Monroe and Alexandria. When I was a kid, growing up in the 90's, we drove that road.. oh, once a quarter or so, on the long drive from Baton Rouge to Monroe to go visit a friend or do a bit of fishing up at lake D'Arbonne.
A thousand people live in Clarks, but... I can't remember that town. There is *nothing* there. A McD's maybe? I'm sure there's a local diner, but who stops there? Even if you do, it's likely only for gas and smokes at best.
Nothing *ever* happens in Clarks - at least nothing that makes the news. I'm sure there's crime and drugs and the local sheriff has things to do, but.. it's so forgettable it's anonymous.
Here's the current news aggregation from the city:
<https://www.newsbreak.com/louisiana/clarks>
NOTHING happens there. Ever. The closest news is from the next Parish over. It has no particular industry, no real reaon to visit, isn't near a park and exists basically in a giant area of nothing.
That's what you want. You want a town like Clarks - it doesn't even have to have all of those crazy safeguards. A post office staffed by the locals. The ENTIRE PARISH has ten thousand people - your IMmortals could run the entire parish government by holding four or five key positions.
<https://en.wikipedia.org/wiki/Caldwell_Parish,_Louisiana>
Everyone thinks it's a big deal to hide - but it's not. Everyone in Clarks knows everyone else - literally. There's no reason to stop, nothing to see - if you don't have business in Clarks, why even bother worrying about it?
You didn't know about the town 'till I mentioned it.
The US isn't filled with big cities - it's filled with forgettable backwaters like this one. Honestly, that's all you really need.
[Answer]
**Place the town in the centre of a large nature reserve/park. Some sections of the park may even be open to the public. But the town itself and some sections of park is reserved for "park maintenance employees" and their families. Everyone knows about the old parktown, can talk about it in day-to-day conversations but non-residents are restricted entry.**
Many years ago, a wealthy tycoon decided to create several large nature reserves/parks across the country in order to protect the environment/endangered species. Each of these parks are run by employees who get to live onsite with their families in dedicated parktowns. Park employees even get added "access benefits" at the other parks and parktowns around the country! Who doesn't want to apply to work at these parks!
Because of the somewhat isolation or distance from towns outside the park perimeter, it is known that these parktowns are fully operational with on-site schools, shops, police, social and medical services. Human-passing employees work the various curio/food/craft shops around the park perimeter and as park rangers ensuring human safety (and compliance with non-entry). Nonhuman-passing employees work back-of-house etc.
To help with the seperation of work/life and give employees and their families time to unwind and relax, away from "demanding customers", these towns purposely exclude non-residents (although occasionally a non-resident does ignore the no entry signs/barriers across the roads leading to the town, with ensuing drama).
Edit: As a frequent visitor to various parks/reserves, I know the following rules/features would raise absolutely no eyebrows.
* it is not uncommon for various internal roads to be marked as "no entry/staff only". Some even have barricades to stop the really inattentive/self-absorbed guests from proceeding.
* it is not uncommon to see some roads closed off as "temporarily closed" due to flooding/damage or area regeneration efforts etc.
* Advertising your park/reserve as holding various dangerous animals, will allow frequent signage reminding guests that absolutely no camping/hiking is allowed. Entry at the main gates would make this clear to the guests and they could even be made to sign-in and sign indemnity papers. Humans will be stupid and try get out of their cars but they do so at their own risk.
* typically internal park roads are designed by the park to get visitors the best views while also allowing some secluded areas for animals to get away drom the human noise pollution (and protect critically endagered plants or animal/bird nesting sites). These particular parks in question could easily design all internal roads that can be accessed by guests to avoid huge swatches of nature preserve, without guests even being aware that they have been diverted (personal gps machines were not common back in the 90's). Only by accessing the "staff only" roads would anyone be able to get anywhere close to the park town.
* park employees and families will know all the best spots to get away from the guests. Including which regions of the park are out of bounds to guests etc. Park rangers patrolling the parks will be able to ensure guests stay to the guest roads.
* Those non-human's that can't control themselves attacking humans would be a danger to any solution to the OP's question and would be subject to internal control by the town leadership.
[Answer]
Disguise the place as a sanatorium for hosting people suffering from an untreatable and deadly disease. Outsiders will be happy to not poke their nose into that place and whoever has to deal with it, out of fear for the disease.
If you want some real case example, the communities hosting leprosy afflicted people in Japan are a good one, as you can see in the movie [Sweet Bean](https://en.wikipedia.org/wiki/Sweet_Bean)
>
> The film centres around Sentaro, a middle-aged man who runs a small dorayaki shop in the outskirts of Tokyo. The shop is frequented by locals as well as secondary-school pupils. When he puts up a notice saying that he is looking for a co-worker, he is approached by Tokue, a lady in her mid-seventies, who states that she has always wanted to work in a dorayaki shop. Sentaro initially rejects her application, afraid that the work would prove too much for the old lady who, moreover, has somewhat deformed hands. He is swayed, however, when he tries Tokue's bean paste; its taste and texture are far superior to that of the factory-made bean paste Sentaro has been using. Sentaro asks Tokue to start making bean paste with him, revealing that up until now, he did not actually like his own product.
>
>
> Business begins to thrive, and very soon Tokue also starts serving customers and packaging dorayaki. However, when customers realise that the deformities to Tokue's hand were caused by leprosy, they stop coming, and Sentaro is forced to let her go.
>
>
>
[Answer]
Rumors are your friend! Everyone knows that *that town* has bad vibes. You don't want to be there, and especially not after dark. Sure, there's money, but it's tied up with the mob or with gangs or something. People die a lot (maybe they don't, but doesn't stop you from spreading rumors. It's not even supernatural stuff, it's just people being crappy. There's never enough evidence to convict. You heard a tourist was killed a few years ago, but the investigation never found anything. There's not even anything to do, unless you like touring (insert utterly boring thing here). Why would you go there? It's probably called something like Washington or Centerville. Some super-common boring name. The reputation is for it being generally unpleasant with nothing about it worth seeing, and it's in the middle of nowhere, so you'll only find it by accident if you're REALLY lost. You could also combine this with one of the other ones, like a blocked road or something.
[Answer]
**Military compound**
There's so many military facilities all over the US, and almost as many acronymical organizations behind them that one or two more wont stand out. Whoever decides to dig into the organization behind gets a friendly meeting and is either brainwashed, bribed or sucked dry. Whoever comes close to the compound sees a fence, some signs, and maybe some burly, strangely hairy guards. Whoever tries to fly a drone over the compound suddenly finds their drone attacked by bats, or has some really pissed off officials of the W.O.L.F. (Weapons Overhaul and Lethalization Force) knocking at their door. Heck, since being part of the US defense portfolio, your compound even gets official funding without having to produce any returns.
[Answer]
Consider the example of the monastic community of Mount Athos in Greece, which keeps out women - indeed, all female creatures other than cats & hens: <https://en.wikipedia.org/wiki/Monastic_Republic_of_Mount_Athos>
[Answer]
Steer Into the Skid.
There are a variety of towns that are known for their population of bizzare individuals and actually market themselves that way. There are plenty of cases of "Keep [Santa Cruz, Berkley, Portland] weird" campaigns which basically is the entire civic administration saying to the world, "You wanna be normal? This isn't the place for you!" If those are too left of center weird/ wrong coast for you, you have New England communities and the entire state of Florida for your East Coast weirdness. Vermont is generally Canada but in the U.S., and was briefly an independent nation from 1777 to 1791 and does not forget it. It also has a habit of electing independent candidates to Congress and has the 52 best GDP of any state in the union (including DC and PR), so there isn't a lot of reason to go there (It does have the 34th bed GDP per Capita, so there is money, just not alot of economic activity). Maine is another great state for a weird small town as the state is generally divided into two regions: Creepy Maine and Really Creepy Maine (Coastal and Interior) with the latter being sparsely populated and very little reason beyond camping for tourists to visit. Maine also happens to be the home state of Stephan King, who sets a plethora of his horror books in the state.
Finally, for a state on the East Coast that's perfect for Vamps, but no one would suspect Vampires to actually be, one must look further south to everyone's favorite freaky state: Florida. You have your choice of locations too. Tiny Coastal Town that has a small reliable tourist community to nibble from (don't worry, all those bodies are just alligator victims) or an interior podunk (seriously, find a major town east of I95 that isn't trying to get that Disney Money. I'll wait...) which is likely built up around agriculture (Oranges or Cattle... nothing else). Sure, it's the ***Sunshine State***, but between that and the typical antics of Florida-Man, a small town of vampires is normal for Florida.
[Answer]
*Managed engagement*. Your town is normal, innocent, not very wealthy. It has double the RDA of coal tar in the water, the unemployment office posts online ads for jobs that are six months old and *never* get filled (except by particularly tasty young unpaid interns). There is "no reason to go there", but people do - the local convenience store has an ironclad contract with local leaders in soda and chips that disheartens rival vendors, their truck goes there every day, and the person who drives it and unloads is utterly enthralled by the vampires. There are some state cops who do a daily patrol - ditto. The state sends road inspectors who make predictable reports. Bored kids cruised their car there and said the local factory smells like vomit and they can't see how anybody lives there.
Basically, the town leadership predicts every type of interaction that they would be expected to have with the outside world, formal or informal, and charms the people who would make it *in advance*. They then serve as a sensory network to report back if anyone else is considering entry.
Despite all this, you still have a huge problem with aerial surveillance. If people are flying around with Tinkerbell wings the NRO is going to know about it. Also their counterparts around the world. How do you charm secret agents in many different countries? I assume your vampires don't really rule the world or they don't need a sanctuary. I don't see a bright future for your people under all-seeing Jove.
[Answer]
**Just hope you like flying**
It really depend on the size of the city, but as long as it doesn't require too much logistic going in it would be pretty simple, just don't connect it to the road network. if you place it in some valley in the middle of nowhere far from any landmark, you won't have anybody to find it even by chance.
Just create an airport the the scale needed by your city. sure it will be a bit expensive to import produce, but you won't have to pay for a massive security that are required by some other solution. and it is pretty unlikely that people would do 100km offroad , traverse a forest and a montain in the middle of nowhere, and even then you could probably see them coming form a mile away "ho, a beated up, covered in mud van, let's call the police"
And the other added benefit to this solution is that it won't really trigger people interest if it don't look forbiden to access it, just difficult.
[Answer]
## Practice Aggressive Redlining
There are local employers; they never advertise job openings to non-Immortals (or people otherwise in the know). They never hire non-Immortals. Homes are not available for sale to outsiders. Apartments are not available for rent. By common consent, the community excludes "people who would be a threat to the community".
There is not a hotel or motel (obviously situated) in town, though one may be subsidized far enough outside of the community to provide a place for residents to direct people there who were just passing through.
If someone who is a threat to the privacy of the community somehow manages to come into possession of property in or near the town, they are actively snubbed (or, for a darker turn, harassed and threatened) until they get the idea and leave.
Care is made to be sure no major highways or other roads run through the town (or parts of the town that are close to major streets passing through are only populated by those who can "pass" as normal mortals). The more obviously visible parts of the town are calculated to be uninteresting, so as not to attract tourism, or any attention at all.
## Be Friendly to outsiders - as long as they are only passing through
It will call attention to the town if obvious hostility was shown to outsiders. Your townsfolk are friendly (the ones who aren't hiding when "normies" are in the neighborhood). It's just not possible for an outsider to settle down there.
Also, news travels fast on the occasions when someone who doesn't belong has shown up. There may even be residents who appointed to follow and keep tabs on strangers (in a friendly, "helpful" way).
(Recommended reading: [The Santaroga Barrier](https://en.wikipedia.org/wiki/The_Santaroga_Barrier), by Frank Herbert)
[Answer]
# No electricity
Due to their claimed religious beliefs, the citizens of your 1990s town refuse to allow electrical or Internet service to be placed in the town. Outsiders will have no interest in spending time in such a place. (Seriously, how long would *you* stay there?)
Such a strategy works for the Amish. As long as they pay taxes and commit no crimes, they are left alone.
[Answer]
With a little help from the US government, have the area declared part of the US's nuclear weapons program. Several cities (<https://en.wikipedia.org/wiki/Oak_Ridge,_Tennessee>) were fenced off and had guard posts (<https://en.wikipedia.org/wiki/Oak_Ridge_gatehouses>) to prevent entry by unauthorized people as part of the Manhattan project.
For bonus points maybe it is actually a toxic waste dump for material processed in nuclear weapons. No normal person would want to live near there, but being immortal they might not care about the extra radiation.
[Answer]
There are two approaches.
One is to create an artificial barrier. This is highly effective as you can legally and completely control who enters. A gated community (as another answer suggested), but it could also be a mining town or another industrial community where everyone works for "the factory" and "the company" owns all the land. A strict religious community could work the same way.
The second is to create a virtual marsh around the community where everyone just gets stuck. First, make the place not interesting. No interesting jobs, no interesting landscape or beautiful mountains. There are lots of such places in the world where people are leaving towards the cities and nobody new settles there anyway. For the few who irrationally want to come and live in Boring As Hell, make them get stuck in red tape and bureaucracy. First you need permit X, to get that you need signature Y. Also, please provide that list of documents. Allow 6-8 months for the approval process. Sorry, your documents got lost, please send again. Meanwhile, that house you wanted to buy isn't on the market anymore. No, you can't rent that appartment without permit Z. Yes, you can get that document easily once you have a job in the town. Please add the permit you will get once you have a job to your job application. Wrong office. Closed over the summer...
If there's nothing worthwhile to get in your community for outsiders, they won't put up with all of that and move somewhere else.
[Answer]
**Let everyone in**
You don't hide it completely. That would not be a good solution. As any place prohibited from access by outsiders will eventually raise eyebrows (See Area 51). And more if it is a civilian place.
You only need that the outside world does not know about the immortality stuff. So you accomplish this by controlling the information.
This can be done with one method in 2 ways. The method is memory/mind intervention. And can be used first as making outsiders perceive the city/place as a normal city/place, by constantly changing what their minds are observing through the senses. The other way is by wiping memories that could not be fixed with the prior method (maybe you can add new memories).
That would also allow for convenient uses like making everyone getting close to the city getting lost in a certain period of time because an eternal event so everyone can be more relaxed.
And as you stated. Vampires have mind control, so they or maybe other eternals with more powerful mind abilities could be in charge of this task.
[Answer]
Research into the ['Vatican'](https://en.wikipedia.org/wiki/Vatican_City) and the ['Holy City'](https://en.wikipedia.org/wiki/Forbidden_City) as (former) real world examples for highly restricted access into populated cities.
Surround the "secret" part of the town with a a ring of normal humans / vampiric thralls / werewolves (when it is not currently *their time of the month*) to deter people coming in. Combine that with using an easily controllable mountain range and build the city for "free exposure of immortal powers" into the mountain. You can leverage some earth faeries magic to build a kind of Menzoberrenzan for those who want to live in.
The big problem with open spaces are paparazzies, telescopes, drones and satellites that allow peeking into the city without even entering it - so hosting a six-armed, eight-legged giant spider half-goddess might pose publicity problems. Same for social networks / youtube - you would need some way to purge leaked information in a hurry - some skilled hackers or techno-mages maybe?
If all else fails - make a public front of an amusement-park (would need tourists) or a hollywood-esk setting for filming fantasy flicks to explain away sightings. Hand-wave the remaining things-to-be-explained using mind-magic and illusion spells.
If nothing else helps, maybe some of the residents have special dietary needs to get rid of people that get too nosy.
[Answer]
## **Frame challenge - ridiculous overpopulation**
Your town has been around for hundreds of years and people are allowed to procreate. But **nobody dies**! Every generation is still around - possibly still having kids - and every new generation has kids and so on.
The population expands exponentially if there are no artifical ways of controlling it - and yet they all live in the same small town with no one noticing.
These immortals with their superpowers will long ago simply have outlived and out-bred ordinary humans. Eventually they will fill the entire world. By that time it will be so overcrowded that death would be a happy release.
Can they even die by suicide?
It doesn't make sense.
[Answer]
### Give it a horrible name
Put it at the end of a long road that terminates in town so you get no through traffic, people dont visit accidentally, they have to choose to visit there.
And give it a horrible name: "pus lane", "boring empty wasteland", "vomit valley", "murder setting", "drab estate", "muggers target", "incest views", "dead baby", "leukaemia lake", etc. You want a name that if used in the sentence: "I did not have a good time at Smallpox Plateau", nobody is surprised.
That way tourists scanning a map decide that the place sounds unpalatable and should be excluded from their tour, especially since it's a 2 hour detour off the highway.
Keep real estate prices high (or make sure theres no available real estate), and keep the absolute minimum shops you need (dont want farmers coming to you cause you have the nearest hardware store).
And spam TripAdvisor with 0-star reviews. "Boring Village is the most boring place on Earth."
] |
[Question]
[
The dwarven legal system is broken. So badly broken that, whether explicitly through legislation or accidentally via a loophoole, it is possible for the victim of a crime to charged, tried and convicted with the crime committed against them, in defiance of all logic and reason. Even the dwarves [find this idiotic](http://dwarffortresswiki.org/index.php/DF2014:Thought#Justice), and yet it hasn't been repealed or fixed.
How would such a law even come into being in the first place, and why/how would it be enforced instead of just being ignored?
[Answer]
Here are a few possible laws and traditions that could create such a situation (some more credible than others).
**Guilty by lack of evidence**
A law was passed to deter people from doing false accusations.
If the plaintiff can't prove the crime did happen, he is systematically charged and convicted for said crime. If the judge asks for too many pieces of evidence (multiple witnesses, culprit's confession, weapon's receipt, etc...), a trial can quickly turn against the plaintiff.
This situation can result from a general culture of mistrust, where the public is prone to doubt everyone's word.
**Blame the victim**
This can take multiple forms (see Tim B and King-Ink answers):
- Blaming people for not protecting themselves enough, for attracting criminals or for being at the wrong place at the wrong time
- Accusing victims of crimes to bring shame to their families, their kingdom or their race
- etc. etc.
These laws can exist in a society that despises weakness.
**The one who smelt it dealt it**
Following an ancient tradition, if the Dwarf Police don't find any suspect during the year following a crime, the person who reported said crime becomes the prime suspect.
**Caste system**
If your dwarf society is structured by a rigid caste system, it could be a crime for a commoner to accuse someone above them in the social hierarchy.
(This is close to the "Blame the victim" solution)
**Blame the boss**
In a society with strong family values, the head of a family could be held responsible for the actions of all the other members of said family.
In this situation, if someone steals from their own family, their grand-mother, uncle or father could be prosecuted with them, even if they are the victim.
The same logic can apply to clans, guilds, companies, etc.
**Someone has to pay**
There is nothing the dwarf government dislike more than losing money. If the defendant can't pay the bill, then the plaintiff has to.
For example, if a homeless dwarf A deface the property of dwarf B, is found guilty but can't pay the fine, then dwarf B has to pay it.
**Administrative nightmare**
The dwarf justice system never doubt the content of an official form.
If the cop who took the deposition mixed up the plaintiff and the defendant's names, the plaintiff will be prosecuted.
---
You can mix some of these solutions together, and maybe add a bit of xenophobia and incompetence to it.
[Answer]
There are a number of possibilities.
Sadly in the real world there are a lot of cases where women (mostly) are prosecuted for "crimes" when they are the victim. For example reporting a rape but being arrested for having extra-marital sex is something that has actually happened recently, we're not talking ancient history here.
Moving away from that though the simplest way would be to have some sort of generic "aiding a criminal" offense that is far too broad. For example if you left a window open and were robbed you helped the criminal in the offence by leaving the window open, or if a criminal were wounded and you provided first aid (whether knowing he was a criminal or not) then again you would be aiding the criminal.
Along similar lines perhaps "providing finance to criminals" is a crime, but by having money stolen you are providing finance for them and fall under the law.
[Answer]
# Strict liability laws.
These are laws for which there is no defense or mitigating circumstances. An example in the real-world would be something like "driving without insurance". If you're caught driving, with no insurance, that's an offense. Because it's not defensible, it's something very easy for the prosecution to process: "Here's the evidence. Prosecution rests".
Combined with **joint liability** laws, you can wrap the legal system around itself and produce bizarre scenarios.
Example:
>
> Urist is robbed in the night by someone on a crime-spree, and a family heirloom is stolen. He informs the guard, and since the heirloom has distinguishing features, they promise to keep an eye out.
>
>
> Months later, Urist is at a second-hand jewelry store, and spots his family heirloom for sale. Not wanting to lose it again, he buys it back and then goes to inform the guard (showing them the receipt).
>
>
> Little does Urist know that "purchase of stolen property" is a strict liability crime: you're guilty even if you didn't know it was stolen (this is to stop criminals who try the old "I didn't steal it. I bought it and didn't know it was stolen" defense). Urist is also arrested for buying his own stolen property (alongside the shopkeeper).
>
>
> Furthermore, when purchasing stolen property, you are guilty by association of the crimes committed when the property was stolen originally (notionally to prevent criminals from making organized gangs: the courts don't have to sort out exactly who stole what). Urist is now guilty of the theft of everything that was stolen that night, for buying back his own heirloom.
>
>
> The local Jeweler's guild uses Urist's story as a cautionary tale of purchasing from second-hand stores, rather than guild-approved resellers. They "encourage" the magistrate (secretly, of course) to put forth the harshest possible sentence for Urist, to better illustrate the risks of dealing with third-party suppliers.
>
>
>
You do somewhat need a bit of backstory as to why the legal system is arranged to screw people. In my example, purchase of stolen property is on the books the way it is due to lobbying from various cartels and guilds (who don't like resellers, and hence make "buyer beware" as risky as possible).
This is also aided by a weak police system. If the police don't generally catch criminals, the ones they do catch need to be sent down with relative ease (in that if they can't spare the resources to actually find the criminal, they're not going to spare the resources to gather a large body of evidence and argue in court for 18 months).
An alternative is weak, voter-orientated politicians who pass laws in response to public outrage that are designed to shaft whoever gets caught in the net (again, without regards to common sense).
>
> Since Urist is an retired solider, there are further penalties applied for crimes committed against a "defender of the Mountainhold". These laws are on the books due to public outrage that soldiers would have property stolen while they were away on duty; stealing from the house of a current- or previously serving soldier now carries double the regular penalty.
>
>
>
All of this comes about because of strict liability. His only legal tactic is to claim that it wasn't him who committed the crime (i.e. you're not guilty of driving without insurance if you're not driving). Since he's waved the receipt of him purchasing his own heirloom in front of the guard; however, that won't fly.
The laws should make sense, broadly speaking. It's *reasonable* to arrest someone dealing in stolen property because it makes it harder for criminals to offload their goods if there are no buyers. It's *reasonable* to have joint liability for some crimes because otherwise the criminals would simply each claim that someone else did the crime, and they were just there as backup. It's *reasonable* to have strong penalties for committing crimes against someone defending the homeland from the goblinoid hoards. It's *reasonable* to have strict liability for most of these things because there's no "reasonable" case where there would be a defense, so why tie up the courts with dealing with the obvious cases of guilt.
You just have to "forget" to make exceptions for the "unreasonable" cases. The laws don't exempt you against committing a crime against yourself; the rest is just paperwork.
[Answer]
If the property values are based on stewardship then not protecting your the stuff in your possession could be seen as a crime against the society.
Letting a heirloom get stolen is a crime against family, Losing a fight or getting mugged is a crime against Dwarf honor etc.
Us humans also like to blame victims for being stupid or not fighting enough.
[Answer]
As was stated in previous answers, this happens in real life. The first case that sprung to mind for me is the case where a ["17-year-old faced 10 years in prison and being labeled a 'sex offender' for possessing his own nude selfies"](http://uk.businessinsider.com/teen-charged-with-his-own-nude-selfies-2015-9?r=US&IR=T).
It boggles the mind that an actual judge who passed the actual bar exam decided that this made sense. So it can happen, but if it happened in fiction it would probably be considered unbelievable. Maybe it would seem convincing in a system that was highly bureaucratic, with lots of litigation. (Kind of like the USA).
[Answer]
A few scenarios inspired by semi-fiction:
* According to "Child 44", in Soviet Russia you could be prosecuted for spreading capitalist lies if you were to report pretty much any crime. That is because "there are no crime in heaven", so of course if you were to report one you are spreading lies to undermine the state.
* Suite Francais: the mayor of the town was executed because he reported a theft from his house. The Nazi occupiers gave him 48 hours to apprehend the criminal or face the charges himself because, under occupation rules, the mayor is responsible for the actions of all the residents in the town.
Both of these would require the dwarven society to be totalitarian with the gears of state being focussed on suppression. In the first case you can choose to go with idealism (the dwarves *really believe* they live in heaven) or corruption (the state uses the ideal as a nice excuse to suppress opposition). In the second case there is no pretence - these rules exist to create fear for the sake of control.
[Answer]
Well, luckily for you it's really easy to create such a loophole. And, guess what, you can even use it in a recursive way if it fits in the situation.
---
Dwarven nation has, among the others, a simple law from the recent past that clearly has been created with the aim to achieve the greater heights of dwarven society. Its scope is to force people to think about the outcome of their actions, to take care of others, to not do bad deeds:
>
> Thou shall be punished for having brought affliction, either intentionally or unintentionally, on one of your brethen.
>
>
>
And it's a real nice law, resuming the spirit of all the other hundreds of laws making up the dwarven legal system, reflecting the hearth of the foundation of the dwarven nation itself (and great achievement of the previous council, pursued for a couple of centuries, carved almost anywhere, etc. etc.)
But it's essentially a law "in spirit", a resume of being a dwarf. Beautiful, enlightening, but in the end everybody think of it as just a direction, not a real law.
Until...a dwarf get caught stealing and reported to authorities.
Until such dwarf get sentenced to jail.
Until...well, guess what? Until that dwarf realize that, by reporting him and having him going to jail, his brethen has actually brought him affliction. Oops...
[Answer]
There's a story in the military here that it's an offense to get a sunburn. The idea is that you'll be charged because you're allowing "government property" to be damaged (you the soldier being the property). While it sounds apocryphal, the military does have weird "catch-all" type laws designed to allow superiors to punish you for pretty much anything they want. The typical example of this is "conduct not becoming a member of the XYZ armed forces." If they can't find a rule or regulation that fits what you've done, that's what you're charged with.
If you were to have your rifle stolen, you'd definitely be charged and punished for that.
I know it's not exactly what you were thinking, but perhaps you could get some inspiration from the idea of it being illegal to allow yourself to be harmed.
[Answer]
Have your dwarves come up with laws where practically any interaction with the watchmen can lead to charges, from "obstruction of justice" to "resisting arrest", regardless of the merits of the initial case. That is, there can be charges of "obstruction of justice" even if there was **no crime at all**, just because somebody irritated the watch. And bleeding on their clean shirts is an assault ...
[Answer]
How about a law that says:
>
> A false-accuser shall be found guilty of the crime falsely accused.
>
>
>
If a crime is committed against you and you accuse the perpetrator, you may end up found guilty of the crime if you're unable to put together sufficient evidence. More likely if the standard for false-accusation is low.
[Answer]
Protection for your own good. You were beaten and robbed, but your assailants didn't finish you off ... yet.
We presume you are in further danger (reference any number of arguments that you're better off killing an opponent than wounding him, since he can't appear against you in court) so until we arrest the perps, we'd better hold you in our nice secure cells for your own safety...
I'm really sorry about this, especially since we think the perps escaped to [Spain|Argentina|one of Jupiter's moons] so the arrest may take a while, but I'm sure you appreciate it's really for your own good.
[Answer]
I doubt you can.
There are laws that I, and I hope most of us, consider as plain stupid. Say, we shouldn't convict anyone (woman, man, or dwarfs alike) for being raped, nor for losing a fair fight, nor for being of the wrong colour, nor for bleeding on a officer's shirt, (as suggested in previous answers) nor ... for a series of as-silly-as-they-get real or fictional laws.
If someone gets convicted according to a *criminal* law than it is because that someone committed a crime *according to that law*. We may think, from our culture, that the law is silly or plain stupid; maybe even those who apply it may think it is outdated. Still, one gets convicted because of a crime, not because of being a victim.
Off course, there still may be the chance of justice errors, of corruption, of police abuse, and so on. It happens.
Say that you report a corruption case but in the end you get (wrongly) convicted for defamation. Still, you are not condemned for being the victim of corruption, but for the crime of defamation. It is an error. It does happen.
[Answer]
Suppose in Dwarvenland, the right to own and carry a sword was protected by the second provision listed in the highest fundamental law of the kingdom. Suppose there was a faction of dwarves in Dwarvenland who strongly objected to this, and attempted to pass laws to restrict the sale and ownership of swords under any possible pretext.
One possibility would be that, whenever a sword is stolen, the rightful owner is to be charged with a crime, either for failing to secure the sword properly, for failing to immediately disclose the theft to law enforcement, or both. This could conceivably have a legitimate crime-prevention purpose (i.e., preventing the proliferation of stolen weaponry on the black market), but could also have a chilling effect, discouraging dwarves from buying and owning the swords they are lawfully entitled to own. What if it was stolen? More significantly, it would cause victims of crimes to be victimized a second time, by the civil authorities.
[Answer]
Yes, very feasible.
**Laws regarding responsibility**
Certain positions are subject to certain responsibilities, and one of the ways to ensure people do their due diligence, is to make it illegal not to. You'd also be reluctant to remove such a law, since that opens up for negligence.
**Example:** If you are responsible for securing some assets (like a bank), then having those assets stolen would mean you broke the law. Of course, stealing is also illegal, but if you had secured the assets properly, the crime of theft wouldn't have been committed. So you are technically to blame for the theft as well.
Poorly structured laws can then deteriorate over time, or have a lot of small amendments made that increase the people covered or the responsibilities of those covered. There can also be constant bickering when trying to fix the law as people are paranoid or greedy, seeing implausible loopholes where there is none.
**Example:** If the law initially was regarding banks, they had the responsibility of adequate security when they held assets worth more than 1000,- *currency*. Which was a big sum 50 years ago, but now it's commonplace. Which means, unless you're *poor*, you are by law responsible for securing your purse.
[Answer]
This reminds me of somewhere where I used to work. If you found a bug in the companies systems you became the person responsible for either fixing it or making sure it got fixed. You can guess the effects...
So, with that in mind.
# Metrics gone awry.
One day the Dwarven King was angry. You see the backlog of unsolved crimes in his kingdom just seemed to grow and grow. He was a king who cared deeply about appearances. He wanted to make sure there were fewer unsolved crimes.
In fact he made it a metric for the nobles in charge of the justice system, if the backlog wasn't reduced then their heads were on the chopping block.
These nobles in turn had to create laws and rules to improve the situation.
At first they tried hiring more guards. They tried hiring more investigators. But this just uncovered crimes that hadn't even been suspected before. With more guards catching more criminals people became more willing to report crimes to the guards.
This was a disaster! The backlog was longer than ever, the king was losing patience and glancing meaningfully at the headsman who was sharpening his axe in anticipation.
And then the nobles had a stroke of genius.
**"Whomsoever doth report a crime is personally responsible for solving the case or making sure it is solved, should the case remain unsolved 1 year hence they shall pay the price"**
It was a resounding success! The backlog of unsolved cases started shrinking, the caseloads on guards was dramatically reduced and people almost entirely stopped coming to the king complaining about crimes against them.
Clearly this policy was the best idea ever! The nobles responsible were rewarded generously.
The nobles in charge of some dwarven counties occasionally objected that the system was flawed... but it could clearly be seen that when they changed things back the reported crime rates under their leadership increased dramatically! The backlog of unsolved cases under their leadership also ballooned obscenely. And so those nobles would fall out of favor and lose their power, or even their heads.
Now, centuries later, it's been deeply enshrined in the dwarven legal code.
[Answer]
Possibly not exactly what you're looking for as it's not the same crime, but you have the old story of the robber breaking a window to get into a house, injuring himself with the broken glass, and suing the owner.
Or indeed the person who's attacked defending themselves and (accidentally or otherwise) killing the assailant, accused of not showing due restraint.
[Answer]
Pay for investigation. The police made efforts to investigate the case. Even if unsuccessful, someone has to pay for the work.
[Answer]
Insanity defense.
The perpetrator claims the victim drove him insane and therefore the victim is the actual perpetrator, as the one whose witting actions caused the damage.
] |
[Question]
[
In an alternative world, matriarchal society is dominated in every way that women always are number 1 position, such as empress, queen, chief, etc. Men can only become the number 2: vice president, advisors, etc. You get the idea.
But there's a strange thing they practice polygyny. You would think a matriarchal society would practice polyandry. But no, only 1% have multiple husbands. Even then it's for special circumstance and high ranking and nobility do it.
In that society, 44% of people practice polygyny.
I know this isn't much. But what would be a good excuse for these practices? Excluding that men are secretly running the world.
[Answer]
**The Real Marriage is Between the "Wives"**
From a genetic point of view it makes sense that only a small proportion of the males get to breed with most of the females. Namely the most genetically fit males with the greatest chance of successful offspring. The remaining males are expendable and can be used for example as soldiers without compromising the species' future.
You are asking for the social point of view. How can we have a situation where females are superior yet often share a husband? The answer is the relationship is not a collection of husband-wife unions with equal partners. Rather it is a collection of woman-woman unions, with the male serving as the second-class partner. He is a stable way for them to have children, rather than wasting energy looking for separate men, and perhaps fighting over the same man to have their separate children. Rather they will choose a man at the start as the genetic father, and that child will have several mothers.
The man is not a husband in the conventional sense of "life partner". Rather he is a designated friend-with-benefits. His position as a fellow human being might be just as high as them. But his position in the family is lower. If they want children he will be the genetic father. He might or might not help his wives raising the child, depending on what the wives want. If he displeases the wives he might be demoted and replaced.
Typically one woman will "propose" to another and the marriage between the two women is the big celebration, with the man playing only a minor role. If each woman has a man already they have to discard one of them. Sometimes neither woman has a man and they find one later.
Families with three women usually form when a two-woman household "proposes" to a third woman. This entails another marriage celebration.
**Bonus:** DWKrauss points out how, in this setup, there is no requirement for a sexual relationship between the wives. It is much more important to marry someone you are happy to raise children with. On that note it might be common to marry a sister or other relative, since you will have similar ideas of how children should be raised, and find a man outside the family. Genetically this is a good idea since it means the child has genetic material from both mothers regardless of who birthed it.
[Answer]
### War (and privilege)
In this society, women are the leaders, generals, strategists. Men are the front-line troops. Leaders are valuable; grunts are expendable. If a queen has the forces to win a battle decisively, well and good. But if it takes sacrificing large numbers of troops to win, she will do what is necessary.
*"I poured out the blood of my armies like water." - [Empress Jadis of Charn](https://en.wikipedia.org/wiki/The_Magician%27s_Nephew)*
In a warlike society with this attitude, male mortality will be higher than female mortality, leading to a population with more women than men.
Now, each woman would *prefer* to have her own husband, or perhaps multiple husbands. But the population imbalance makes it impossible. The nobility use their power and privilege to marry as many men as they please. Everybody else has to settle for what they can get.
In this society, the family name is passed on through the mother. As in many real-world societies, people attach great importance to keeping their family name alive through their offspring. Most women, therefore, place a high priority on bearing children, and to bear children, you need a man. Sharing a husband isn't ideal, but it's better than remaining unmarried and childless.
(It is possible to have a child without being married, but women who go this route are typically looked down upon: it implies that they are so poor they couldn't even afford to share a husband.)
[Answer]
Men are deemed inferior, therefore those few decent ones which happen to be found are used to improve the species, and their only task is to fecundate as many women as possible.
Each chosen one is given as husband to many wives, so that their offspring can produce valuable people.
For the more technically advanced nations the man is reproduced in the same way as race horses are: their sperm is used for artificially inseminate as many women as possible, without physical intercourse. In this way, technically a man has many wives, but practically none.
[Answer]
**The best of the best**
Although it's easy to think from a human society perspective, there can be cultural differences in a human like society that request different ways to mate. One way this can be different is the drive of women to get the very best.
The woman are choosing for the male, not the male for the women. It is accepted for the male to have sex with multiple woman, as it creates the best offspring. Depending on the society there can be a lot of subtle differences. There can be protectionism of the male, where the women that mate with the male decide if he can have more and who can be added to the group. There can be a free for all, allowing any woman to choose that husband. The woman can also have a tight bond between anyone who has chosen the same husband.
The importance here is choice. Societies can look a lot like each other, but differ in how the mates are chosen. In the above examples the men are completely left out. In our own patriarchal society however you do see that women can still choose a lot themselves in many societies. Even in some harem situations, although rare. A matriarchal or patriarchal society doesn't mean there is no agency in the non dominant sex. It just means that the dominant party often has more to say.
The woman have first say, initiating most of the romantic or reproductive relationships. That can make them dominant, even if the men can decline the advances. But if you want to drive the point home, remove all agency from the men.
[Answer]
**There are hardly any males.**
It is an accident of the genetics of this population. Male babies are very rare. Perhaps there is one for every 40 or 50 female babies. Males are so rare that there is not a specific male gender, gender meaning the cultural construct. This society definitely has culturally defined roles because that is what makes us human. But there are none that correspond to chromosomes - genetic males are considered to be the same as the females, except there is one thing that they can do that the females can't, and sometimes they do it.
[Answer]
## Rapid population growth.
Men and women play an asymmetrical role in reproduction: men make their contribution at conception and then are largely superfluous outside a support role, while women are biologically committed throughout the pregnancy (and even beyond, e.g. nursing) and are unable to begin another until the last one is finished. Because of this, men are capable of producing children MUCH faster than women: a man with 10 wives can have 10-20 kids per year, while a woman with 10 husbands can still only have 1-2 kids per year.
If this society has a desperate need to grow its population as quickly as possible, either to recover from some massive catastrophe or out of a need to fill newly-acquired territory, it might make sense to pair politically, socially, religiously, or biologically important men with many women, to produce children as quickly as possible. The only requirement would be a reason why some men are more valuable (or available) than others, to explain why a symmetrical 50/50 population leads to an asymmetrical marriage arrangement.
The nature of the population crisis and the male selection process could be anything, but for a few examples:
* The world is ravaged by a virulent disease which only some people are immune to. Facing a downward spiral of population size, the High Priestess has allowed individual men with immunity to be "shared" by multiple women from important families that need to produce heirs who can survive into adulthood.
* After discovering the Hyperspace Network, the United Federation of Women have begun sending colony ships to habitable worlds. For efficiency, each ship carries 1,000 women as the primary crew, and 50 men to ensure viable population growth for the new colony. After a few generations the gender ratio will naturally even out, but for now each man will be required to impregnate multiple women in order to reach a self-sustaining population size.
* After a devastating war that saw over half the young men die on the battlefield as grunts for their ambitious female commanders, the Empress has declared that each remaining man must take at least two wives to ensure the next generation and secure the future of the Empire.
In every case, socially-inferior men are being paired with multiple female partners, all in pursuit of rapid population growth.
[Answer]
They evolved differently and have fewer men (a variation of Willks answer).
Our society has about 50/50 births of men and women. By the time puberty is over there are somewhat more women than men due to the high mortality rate of male puberty. Subsequently a large portion of men take one woman to be with and the remainder (tries to) have offspring with the "extra" women.
Your society is matriarchal, their structure could have changed to reflect this. If women can "share" one man without the need for competition the need for men goes down. In our society the support the man gives in taking the risky food gathering and child support is a great boon in child survival. In your society the women would provide support and childcare for one another, reducing the need for men once more.
There are so few men necessary that they started being born in lower and lower numbers.
[Answer]
Men do all the lethal work.
They fight as soldiers, they work with dangerous chemicals, they tot around bales on the wharf and get thrown in and drown -- etc. etc. Now, while the vast majority of people who die on the job are male in our society, perhaps there are particular reasons why jobs are so much more lethal in theirs. Perhaps there is large scale warfare, or relentless fights with monsters, or contaminated lands that still must be used.
Additionally, women want only excellent men to father their children. This gives the men a powerful motive to take on risky jobs to show their skills and their courage.
Furthermore, the one set of women who get no benefit from a man is his family. Many of them die in their cradles, sometimes from neglect, others from malice.
[Answer]
**Men are like slaves**
(there are real-world societies that work somewhat like that, but in reverse)
Men are expensive.
Wealthy women have a lot of them and use most of them as a workforce.
Less wealthy women have one (the official norm, but not really a frequent occasion) or just own "shares" of one.
Or they have none.
Renting men is common and there is a competitive market of attractive men that are seen as a status symbol.
[Answer]
In all but the shortest-lived *Utopian socialist* societies, having lots of "things" is a sign of status.
In patriarchal societies, a way for a rich man to display his power/wealth/virility is to practice polygamy. This "works" because one man can impregnate a lot more women than women can bear and raise children.
So... why would a matriarchal society practice what seems to be a sign of patriarchy? Because men are still men: bigger, stronger, more violent. Thus, to pacify them, the matriarchy decided:
1. practice polygyny to keep the men happy, and
2. kill the weak baby boys, so that there wouldn't be an excess of men unable to find a mate.
[Answer]
### Hypergamy.
In the real world, it is widely attested that many women prefer a man who is "higher up" than they are: physically, socially, monetarily, and intellectually; this is called "hypergamy". You can see this reflected in things like the marriage choices of men and women with university degrees vs those without (women with university degrees marry "down" much more rarely than men with them do); IIRC there have also been studies that (heterosexual) women in modern Western societies tend to have more sex than (heterosexual) men do, because many of the high-status men have sex with lots of women, while the low-status men have little or no sex. It has been argued in various Red Pill/manosphere venues that the revealed preference of sexually-liberated women is for them to share high-status men, rather than monopolizing a low-status man.
I've seen it argued that this occurs because of reasons of evolutionary psychology; because of the biology of pregnancy and the heavy costs it imposes, it's in a woman's best interests to obtain the best genes available, to ensure the survival of their offspring - and that because the women who acted this way got a relative advantage over those who didn't, their genes became more likely to propagate.
Naturally, this social structure creates a large underclass of sexually-frustrated men, which in turn results in social instability that has been argued to result in patriarchal societies with monogamous marital norms having a competitive advantage over those societies that stray from this norm; those that strayed from it and remained relatively stable have typically been in situations where low-status men might be funneled into the military, where they might be able to hope to acquire foreign war-brides (though this is unlikely in a female-dominated society where kidnapping foreign women is likely to be frowned upon).
[Answer]
Most of the answers here focus on choosing a partner as a genetic fitness decision. For most of human history, in most places, this has not been the primary concern of the ruling class. Consider how many noble families have resorted to inbreeding, to their great detriment, just for the sake of retaining power within their dynasty (looking at you, Habsburgs).
The rules surrounding how many partners a person can have in the ruling class is almost always an issue of power. The rules of marriage govern the production of heirs, the movement of wealth and political power. A marriage can join the wealth of two families into a powerful dynasty, or it can split up the wealth of a powerful dynasty into smaller less effective units.
[Answer]
*The men are the glue to alliances.*
Suppose that women are the number ones, i.e., all the lords of the realm are female. So, how could Lady-Lord A and Lady-Lord B symbolically cement their alliance?
The method of choice from history would be to marry their children.
However, both Lady-Lord A and Lady-Lord B could marry the same guy. Then the actual lords are united in marriage a trois, in constrast to their offspring.
Furthermore, the offspring of Lady-Lords A and B would be blood-relations.
(Policital) Marriages may end, but being blood-related never ceases.
The husband of Lady-Lords A and B would be a mutual super-envoy, since he has the most privileged access to both rulers.
[Answer]
## To eliminate the notion of fatherhood
Real power in a matriarchal society would flow from mother to daughter, and the notion of motherhood would be strong. The notion of fatherhood would be weakened by the fact that the offspring could be from any man /husband. Men would be isolated. Respected, yes, but only as individuals. Ephemeral, and heirless - not like the chain of daughters.
[Answer]
Elephant-like society.
Females form closely connected pairs that raise the child elephants together (alternating their fertility periods). Few such pairs along with their children may form a large group with a strong (of course female-top) hierarchy.
Adult male elephants live either alone or in homosexual pairs of old and young.
Older males almost always have a priority in mating, so majority of the offspring for a certain span of time and areal shares the same father.
[Answer]
## Hive society
You could model this off the way that a beehive or any colony is set up. The vast majority of bees or ants are female, but most of them are non-reproducing workers. Only the queens are able to lay eggs and produce offspring. The male drones have basically one job, which is to seek out queens in order to mate with them. The difference between a queen and a worker is whether they are fed the royal jelly while pupating - an honor reserved for only a small percentage of eggs. The difference between male and female eggs is whether or not they have been fertilized. A queen will lay eggs even if she has not mated, but these will all be exclusively female, mostly non-reproducing workers. She can only produce male drones if she has been fertilized by a male drone. This necessitates any males to go out and seek queens, often in other hives, because they will not mate with their own hive's queen. (Even an insect will avoid incest - despite those words being anagrams...)
Now to apply this model to a humanoid society, the only change you might want to make is that with these insects, the male is generally killed and eaten after mating - you might want to skip that part, allowing these drones to travel around from queen to queen. (And in this case a queen isn't necessarily the ruler of a whole country, but merely a small group, sort of like little city-states - you might have a hierarchy of regular queens, high-queens, empresses, etc. Give them whatever names you want at varying ranks, duchess, countess, whatever.) You might also allow your males to mate with non-reproducing worker females, but this would be just for recreation and not reproduction. The point being that males would be considerably less common, and a bit of commodity, but only for the purposes of mating. The queens (by any name) are the ones in charge. Some males may be given the honor of queen-consort, mating exclusively with the highest queen in charge, but most would be free agents, consorting with multiple lesser queens (and possibly some workers on the side just for fun).
] |
[Question]
[
In my novel, my main character has come from earth to a fantasy world. She has been reborn on an island of giants (10-meter tall humanoids) where everything is scaled up to match what they would look like to a normal size person.
My question is what could my main character look for to tell that she is, in fact, a giant when compared to a normal person in a world that is scaled up to match her size?
I mean that the trees and rocks and everything around her is scaled up, not just the artificial structures. What physical effects could she notice?
There are no normal sized people in this area until much later on as the area that she starts in is completely separated from the outside world.
What may make it clearer is if you imagine that the world is a 10x scale replica of our world and you are viewing it from an outside perspective, what effects could you observe that would give you an idea of the scale of the world that you were in?
[Answer]
What you're looking for is largely the opposite of what we saw for the [1mm tall robots](https://worldbuilding.stackexchange.com/questions/40633/how-would-i-know-if-i-were-a-1-mm-tall-robot).
Surface tension of water is a noticeable thing, there's a clear bulge that would seem smaller than memory suggests it should on any given surface. Of course we're not looking at such a pronounced effect in this case, but it would be significantly reduced.
Gravity would have interesting effects, jumping or falling body height would have a considerably greater impact than expected. The square cube law would make things like sudden changes of direction inexplicably harder.
Assuming it's the same world, your biggest giveaway could be the distance to the horizon. A 6 foot tall person would see a 3 mile horizon, a 10 foot tall person would see a 4 mile horizon. At 10m (32ft) tall they're looking at a horizon distance around 7miles (11km). This is a non-linear relationship, the taller you get, the closer your horizon appears to be. The world seems ever smaller.
[Answer]
**Gravity - Time of fall.**
Assuming they live in the same gravitational field as the non-giants then simply drop something and see how long it takes to hit the ground.
A normal human is about $2m$ tall. It takes an object roughly $0.6$ seconds to fall $2m$ in our approximately $10\, ms^{-1}$
A $10m$ fall would take about $1.4$ seconds.
The relevant formula is :
$$t = \sqrt{\frac{2h}{g}}$$
**Edit : From discussion in comments, I'll add some explanations.**
Even without having previously e.g. dropped things and measured the time to fall you would notice this difference. It would be like watching things fall in slow motion - very obvious to anyone in an instant that something is off.
It might take you a little effort to work out exactly *what* is causing the "slow-motion" effect you see, but you would get to the fact that you're bigger than you used to be.
This effect would be less noticeable if you were not quite so tall. For example the fall from $4m$ (still twice normal human height) would only be $1.4$ times longer (a change from $0.6 s$ to $0.84s$) and you might not notice that before you mentally adapted to the new environment. But the $10m$ tall human would find the change really big and much harder to "adapt away" or dismiss mentally.
Note that this would also be jarring because your horizontal speed of movement would not seem to change, while time of fall did. Your gait and walking speed might seem more like normal when you scale up size, but you cannot fool gravity, so you'll have a permanent inconsistency between the apparently normal horizontal walking speed and vertical motion. This would be hard to ignore.
[Answer]
I'm assuming the new giant is made out of materials and mechanics that can support the weight and don't cause problems with the person itself. Otherwise her bones would break more easily (not guaranteed, depends on how much of a giant she is) and she would overheat like crazy (less surface area to lose heat compared to the volume that generates heat).
Liquids have less cohesion. Think of a droplet of water on a leaf, you won't see that kind of thing when you are big as the water would pool more. Blood loss will also be much worse, as you'll lose a lot more and the flow rate will be higher, making it harder for the blood to clot and seal the wound.
[Answer]
>
> My plan is to basically use magic for a localised weight reduction on the giants themselves. They are still physically as dense as they would be but weigh less. The world around them will still have normal gravity.
>
>
>
Will their physical strength be scaled to their inertial mass or their weight? Because you've now made those different (by a factor of ~5 for 2m -> 10m height), to overcome the square-cube effect!!
If their strength matches their inertial mass, they can change direction as quickly as before, **but jump very high**. (Or lift/throw objects of their own weight very easily.)
If their strength matches their weight, so it's about equally strenuous to stand up, or do yoga / plank / push-ups, then **they'll find it much harder to pick up objects of the same apparent size.** And they'll find it very hard to get up to speed / **change direction when running**, with 5x the momentum they're used to relative to their strength.
---
If they start to notice a discrepancy and try to investigate, they might use a rough balance (like a fallen log) to find something of their own weight.
## Or maybe more simply, they will float like a cork in water
Because their gravitational weight is ~5x less than it should be for their volume.
[Answer]
Small soap bubbles behave differently than large soap bubbles.
Small soap bubbles start out as blobs but quickly form a well-rounded sphere. They then float around with a stable "tight" outer surface.
[](https://i.stack.imgur.com/7kkfc.jpg)
Large soap bubbles start as amorphous blobs and they stay that way for a while, and even when they start to round off, they are usually only as round as a potato, which is noticeably different than a perfect sphere. And as they float around they continue billowing and changing shape:
[](https://i.stack.imgur.com/w7o9j.jpg)
This is because of a molecular property of the soap. Unless you scale up the actual soap molecules, this effect will remain. So if your protagonist tries to blow a spherical soap bubble on a whim, it will not look or behave the way they expect, because what they think is a small bubble is actually a giant one.
[Answer]
**Health issues, bodily proportions and mass**
Depending on how realistic you want it, and how faithfully everything is scaled up, she'd probably find out by the numerous health problems she'll encounter pretty quickly. Undersized heart and undersized joints and bones in the legs for instance. This would be shared by pretty much all living things (trees scaled up beyond the limits of their current biology would either fall or die off at the top).
If we're assuming that things have been scaled up disproportionately to allow for these things not to be a problem, she'd probably notice her legs are proportionately bigger as a start. People are pretty intimately aware of their own bodies' proportions, so changes will be obvious.
The next most obvious thing might be mass. Bigger things take disproportionately longer to accelerate and decelerate due to the square-cube law causing weight to increase at a greater rate than size. Anything she manipulates will feel disproportionately heavier (even accounting for her added musculature). Whatsmore, falls would *hurt*, so if she tripped and fell she'd be able to work out something was off. Provided she's young and healthy it's not normal to be thoroughly bruised all over from a simple fall.
[Answer]
[The green flash](https://en.wikipedia.org/wiki/Green_flash).
>
> Green flashes and green rays are meteorological optical phenomena that sometimes occur just after sunset or right before sunrise. When the conditions are right, a distinct green spot is briefly visible above the upper rim of the Sun's disk; the green appearance usually lasts for no more than a second or two. Rarely, the green flash can resemble a green ray shooting up from the sunset (or sunrise) point.
>
>
>
The green flash is seen at the horizon during sunset/sunrise.
And we know that the distance between the observer and the horizon depends on the elevation of the observer above the sea level.
In principle, if one is laying flat on the ground when observing the green flash, by rapidly standing up another green flash can be observed, because by standing up the horizon has moved slightly farther. This is already cool because one can see 2 green flashes close to each other. However..
For a normal human the height change will be about 2 meters at best, while for a giant it will be 10 meters: this will have a measurable effect on the time separation between the two green flashes, which will have a larger separation than the one measured by a normal human.
By comparing the two time intervals your character can conclude that her body has increased in height.
[Answer]
**Beach Sand**
Your giant will see what looks like silt sized particles behaving like sand.
Sand particles can't get below a certain size and still behave the same way. If sand is worn down to a powder like consistency it becomes silt which behaves in different ways, (when wet it can't reflect enough light to look white for instance) if it is worn even more water will chemically alter it into clay. Thus white beach sand particles never get below a certain size. More importantly to have sand dunes you need, well sand, silt will not form dunes. the closest it can get is loess hills which do not happen in wet environments. If your character goes to the beach they will notice the white dune sand looks like powder which can't happen. It is pretty big leap to "I'm a giant" but it could certainly give hem their first clue, and it would be concrete evidence not just a feeling. If they know a little geology it will be a very glaring issue.
If they can get a hold of a strong magnifying glass or low powered microscope they can confirm it is shelly beach sand (made largely out of shell fragments) and thus cant be silt. Finding a bay with normal silt in it will help confirm as well. Sand also behaves differently than silt, a footprint in dry silt will not fill itself back in the way sand will. The can further confirm with a simple soil testing trick using a jar. if you mix sand and silt with lots of water and then swirl it around the silt will stay suspended in the water a long time but the sand will fall out. Scale will not effect this.
## Also cooking is going to take forever.
A normal steak can be cooked over a wood fire in few minutes a giant steak will take hours. Making a wood fire bigger does not make it any hotter, wood still burns at the same temprature. The surface area to volume of giant objects is much lower so heating them takes much longer. A pot of soup will be an all day affair.
[Answer]
It takes time to send commands and receive sensory feedback along the length of a nerve.
Having longer limbs, your character may experience a delay between asking a finger to move and then seeing and feeling it move. Just enough to feel slightly inebriated. They could acclimate to this sensation eventually.
[Answer]
If giant humans are proportionally stronger, and all health & movement issues are handwaved away, there is still a number of things that would give the scale away.
1. Water tension (already mentioned in the other answers). If water tension remains a constant, it would look very different for 10-meter tall persons.
* Drops (raindrops, condensed mist and just accidental splashes) would look tiny;
* Pouring water would look different;
* Ocean waves would look funny (knee-high surf with "white horses");
* Just water in a cup would look different - a visible ripple on the surface (while in a human-sized cup water tends to stay perfectly still);
2. Material toughness. Many day-to-day objects would usually survive 1-meter fall from one's hands with minimal or no damage. Same objects, if scaled up, would shatter if dropped from 5-6 meters. Softer ground would be swallowing giant's feet;
3. Invasive/migratory species. Are only the "giant" versions of animals allowed on the island? Any normal sized seagull or dolphin would become a surprise.
[Answer]
If all the limbs are bigger, then the heart will beat more slowly : it will need more energy to push all the blood necessary and the heartbeat will slow down to 20 to 30 bpm (20 is the whale, 30 the elephant). The character could make an effort that'll left him/her exhausted, and sense his pulse at a horrendous slow rate in his head.
[Answer]
I assume that if everything scales up x10, then so do the units of measurement. So 1 meter in the new world would be equivalent to 10 meters in this world. Clearly measuring herself would be useless.
However, your main character can **measure the speed of light** (or ask around to see if anyone else has measured it). If it's given as 30 million meters per second, then she knows she's a giant. Furthermore, she knows the exact scale to which she grew. (The actual speed is about 300 million m/s.)
Whether the speed of light can be measured depends on their technology, I guess. But in our world it was measured as early as [1676](https://en.wikipedia.org/wiki/R%C3%B8mer%27s_determination_of_the_speed_of_light) by Danish astronomer Ole Rømer. Basically, he noticed that Jupiter's moon Io took longer to finish its orbit in periods when Earth was moving away from Jupiter in its own orbit around the sun, than when Earth was moving towards Jupiter. Because we also roughly knew the distance from the sun (which was known earlier), the relative angle of Earth's orbit with respect to our separation from Jupiter, and (obviously) the orbital period of Earth around the sun, we know the speed of Earth with respect to Jupiter. Given this and the delay in Io's orbit, it's quite easy to calculate the speed of light.
[Answer]
At 10 meters, the ambient temperature differential between your head and your feet would be far more noticeable. Outside, you'd notice that it seems really cold when you're standing up and much warmer when you're sitting on the ground or lying down. Indoors, you might detect the opposite, as heat tends to rise and get trapped at the ceiling. Either way, you'd definitely notice a distinct difference in temperature between standing and sitting heights. You might even notice that the atmosphere is thinner up there, resulting in your breath being shorter when standing than while sitting.
[Answer]
Maybe a good way to tell if you're a giant is gravity. If the gravity in this world is the same from earth, she'll notice that she's heavier and that something doesn't seem quite right. Also, you can put on some normal sized animals, or giant sized animals, but not as big to scale to the Giants, so she'll see familiar animals but smaller and start questioning things.
[Answer]
Simple, just jump up and down.
Creating a crater when you jump is not normal, it would certainly make the character realize that something is wrong.
[Answer]
Is this a trick question? Her weight will be 10X, if she had a weighing scales , she will suddenly be 10 times heavier!
So she could observe the effect of the dial going from ~50KG to ~500KG
] |
[Question]
[
**Is it possible to create a room-temperature solid made from 100% human blood?**
---
One of my stories features a girl who has the passive ability to block the superpowers of anyone in a 100-meter radius. The government decides that this would be quite a nice power to have - for example, building a supervillain prison in which the villains can't use their powers. So they take a sample of the girl's blood, so they can use it to make some kind of solid material with the same properties.
Assume that the government has some kind of advanced Handwave Machine that can produce genetically-identical blood, and that the blood retains the "passive-blocking" ability, but diluting it with other substances proportionately weakens it (so for example, something that's 60% blood and 40% iron will only have a 60-metre blocking radius).
With that in mind: Is it possible to create a room-temperature solid made from 100% human blood? If not, what material(s) would you have to mix in to make this possible? What physical properties would the resultant material have? It doesn't need to be super-strong, just strong enough that it could be used in floor/wall tiles.
---
**UPDATE**: Thanks for all the amazing answers so far. A few clarifications, since the comments have been moved to chat:
* The ability is an intrinsic property of the girl's blood and can't be separated out (i.e. via centrifuge). It has to be the blood.
* Since most of the answers seem to have focused on the "supervillain prison" example, I'd like to add that that's not the *only* place it's used. It's also used in important buildings (government offices and the like) to deter supervillain attacks. This is also where the radius part comes in - it's preferable in those buildings to use only a few strategically-placed tiles, rather than covering every wall with blood and creeping everyone out. This shouldn't invalidate the existing prison-oriented answers, as they still work great.
[Answer]
You don't really need the blood to be solid. Make two layers of solid brick wall, and fill the middle with layered blood bags.
## UPDATE
Since you want *visible* blood: make "fishtank" walls of bulletproof glass, about .5m thick, and fill them with blood. For extra effect, you can pump the blood around the tank to make it swirl, or add bubbles
[Answer]
# Bloody Paint
Why bother turning it into some kind of structural material? Just use it as the paint on *literally every surface* with this girl's blood. It'll be an awful color when it dries, but if dried blood still works, use it as paint. Walls, floor, ceiling, the bars on every cell. The stuff will be everywhere, radiating its effect from every direction, and it doesn't matter how weak the effect is, it's *on everything.*
# Bonus Effect: Bloody Bullets
Coat all your ammunition with it too, every bullet, taser prong, sliver-needle, blade, and club.
Why?
Why not! Even if it's just a little bit and has a reduced effect, firing it directly into your ~~contained~~ escaped monsters/villains/whatever will still have a non-zero effect on their powers. Maybe the coating will even allow the bullets to penetrate those guys with the armor-skin (I mean, even if the blood-bullet has an effect radius of 1mm, that should still enough to weaken superskin at the point of impact, allowing penetration).
Sorry if I turned your plot device into a way to neuter every mutant ever, forever (just give them a blood transfusion).
[Answer]
Blood will turn into a gel if left on its own. Just put it into plastic containers and use that as a building block.
[](https://en.wikipedia.org/wiki/Blood_as_food)
[Answer]
This is a great idea, but I think by opting to use solid blood building material you're missing out on the opportunity to have blood piped into the prison, constantly dripping from the walls and ceilings. (Or... Why not both?)
However, as a reader I would question why you need 100% solid blood? As you put it, the radius of effect scales down linearly. Say your prison has hallways 5 meters wide. If you use 2.5% blood-content cement, the concrete alone would be good enough. Why not have a 3 meter tall cell with blood floor/ceiling tiling? Then 1.5% suffices. And if you use tiles, why would every tile need to contain blood? You could even use one tile every square meter of floor tile a blood-tile.
May I also suggest inverse square drop off? It won't make much difference on the low percent content you need, but it is inline with most physical laws. Gravity, magnetism, etc.
I would also wonder why the prison guards aren't clones of the girl. Or why they don't get blood transfusions of her cloned blood.
And humans are considerably less than 100% blood by volume or mass. Would a 100% blood solid have a larger effect radius than kind of blood/muscle/bone/flesh mixture in the girl?
I think even without the dripping ceilings or blood tiles, you could give the prison itself an artificial circulatory system. Blood in constant flux through pipes seems promising. Maybe building engineers could find a way to use blood like a refrigerant...
And as a reader I would ask "If dried blood works, why not make every building and every piece of infrastructure contain some of her blood? Or paint road stripes with dried blood?" That would do away with the super-villain threat every except Rural areas. Building new infrastructure across America just to pump blood would be a non-solution though, due to investment cost, upkeep, and the time needed to implement it.
[Answer]
I've heard rumors that blood was used as an ingrediant in Roman Concrete. Google: [Patent US4203674](http://www.google.com/patents/US4203674)
Concrete that nullified superpowers seems like a great material for a prison.
Added bonus: you can say that the prison architects got the idea from Roman sources as the Romans developed the technique to contain "Magic" prisoners...if that even fits or something.
[Answer]
## Blood vapor
Since the other answers have covered the solids (walls of blood gel) and liquids (paint, coat everything, mix in water supply), permit me to propose another phase: blood vapor. You could have [atomizers](https://en.wikipedia.org/wiki/Atomizer_nozzle) installed throughout the prison which spray fine blood into the air at regular intervals. So your inmates will stay depowered provided you maintain sufficient density of blood in the air.
## Bonus:
* **Blood spray**: Instead of pepper sprays, the guards walk around with blood sprays.
* **Blood-smoke bombs**: You could use this idea to make blood-smoke bombs which the government can use to suppress peaceful (or violent) demonstrations by superhumans. If the government soldiers are engaged in combat with the superhumans, using these bombs will have a large area of effect and be more useful when compared to blood-coated bullets or blades as the government soldiers will be unaffected (assuming they are not superhumans).
* **Blood mines**: Strategically place and prime the blood-smoke bombs (as mines) on the perimeter of the prison as a line of defense for escaping/attacking superhumans.
[Answer]
So if you are going for a visual effect I think it could be really neat to have the prison be covered with "veins" everywhere. Essentially it could look like a venous system that humans have. This would give a visually stunning appearance (my own personal opinion having looked at the venous system before) and give you the opportunity to weave in other elements into the prison if you so desired (say for instance the prison is a living entity or something). Of course this doesn't make it a solid but you could always make it into a solid spiderweb design if you so desired.
[Answer]
As an alternative, fit prisoners with collars. In movies and anime, the collars would be fitted with explosives or toxins; in your case, you can have them contain the girl's cloned blood.
This way less blood is needed compared to using it as building material or paint; it also won't stink up the place.
If the collars have very difficult to break fiberglass tubes, you can have dark red fluid sloshing around inside and retain the visual impact as well.
[Answer]
*Hemacite* is a hard material made of compressed blood and sawdust that was used in the late 19th century for items like doorknobs, buttons, and roller skate wheels. See [At Death's Doorknob](http://cabinetmagazine.org/issues/9/leftovers9.php)
[Answer]
Idea 2: Dilute the blood in the water supply, if the blood is potent enough.
It could run through the pipes in the walls in all directions. The prisoners will drink, eat, shower, sweat and piss it everywhere, they'll be their own "de-powering" nodes. The effect can last a while outside the prison. If the property doesn't degrade and the water is recycled the concentration can accumulate over time.
The guards give the prisoners placebo pills posing as the neutralizing agent. They make a big deal to enforce their administration to decieve the prisoners as to the source of the agent.
[Answer]
How many prisoners have you got? I feel you're approaching this wrong looking for a solid.
People manage to get out of prisons. All the time, even without super powers.
The most effective prisons make it so that getting outside the walls is just the start of your escape. Stalin sent political prisoners to Siberia for a good reason - escape means freezing to death or the guards easily tracking you through the snow.
Your setup would make it too easy for prisoners to escape far enough to regain their powers, and from there, they will get to safety.
Any physical object, even one buried in the skin could be fled from by a determiend prisoner.
But you can't escape from your own blood.
Assuming the girl has O-type blood ([the most common type](http://www.redcrossblood.org/learn-about-blood/blood-types.html)), you can simply inject 0.0008 pints of her blood into each prisoner, every 8 weeks (blood wears out after [120 days](https://health.stackexchange.com/questions/1694/how-fast-is-blood-replaced-in-the-body), but we need a factor of safety as the injected blood won't be brand new). This would leave the prisoners blood 0.01% antimagic, which should have a range of 1 cm. You can't be more than 1 cm ft from your own blood, so should be safe.
Many people donate a pint [every 8 weeks](http://www.redcrossblood.org/donating-blood/donation-faqs), so this should cover 1200 prisoners.
Get some friendly superheroes to help you test these numbers. Maybe you can go lower than 0.01% (1 cm range) if the magic source is an organ that receives bloodflow.
More than 1 pint/8 weeks may be possible with advanced medical care for the girl, and with her not performing any heavy lifting, driving etc.
[Answer]
**Blood bags**
Specifically, the fleshy kind...
Instead of just collecting the blood, you instead gather enough material to begin a cloning program; only there is no need to create proper clones, you just need some internal organs and a cardiovascular system, resulting in 'flesh bag' blood generators.
Instead of some blood based paint that would likely degrade, or changing the nature of the blood, which could destroy whatever is causing the effect, you how have a large number of living null-field generators that can be hooked up to small life support systems.
It's a different visual impact to raw blood in vials, but still a big one. It may also fit better into how power systems may work in your world. Usually, there is little to no lingering effect from a power. Your world may be different, but if not, this may be more internally consistent, than having blood somehow retain its ability when no longer part of a living creature, and not having an isolatable active ingredient producing the effect.
*note: blood carrying effects e.g. vials of blood in pendants etc, is typically more common in a magical setting, where it is the ritual etc of producing the artifact, or magic cast on the blood that causes the effect, allowing it to last while also being a non-physical feature, so being unable to extract it. If magic is a superpower in your world, then you could make it a magic based power*
] |
[Question]
[
Context: The setting is a future where the planet is pretty much a giant city and due to reasons has become a post-apocalyptic landscape. Humans are long dead and the only sentient life left are the robots and androids the humans made to serve them. Due to neglect, system failure and a rather nasty computer virus, some of these bots have gone... feral (for lack of a better word). In this case, many of the surviving robots have armed themselves for protection and to hunt the feral ones for the parts needed to survive.
Now, to make an entire planet a city and develop sentient robots we're talking tech levels waaaay ahead of us. So plasma rifles, railguns and all manner of fun military toys could have existed, but I am enamored with the idea of a humanoid robot walking through a giant, ruined city with nothing but a backpack full of parts and a lever gun or tommy gun in his metallic hands.
So the question I need to ask is - how could I make it where that level of tech would be common in this setting? And yes, the robots would be making this tech themselves, not just grabbing old Winchester leverguns and Colt peacemakers from museums.
Currently the only idea I have is that railguns and plasma guns require a lot of high-tech equipment to build and maintain. Whereas 1870's-1940s (or 1960s even) tech is simple in comparison, so the tools and machines that can produce firearms and remain in operation are better suited to this older level of tech after centuries of neglect.
And as mentioned previously, the older tech would be - at least theoretically - significantly easier to maintain. Ammunition itself could additionally remain relatively advanced (e.g. explosive rounds) with few modifications to the firearm for that time when a robot needs to defend itself from others.
[Answer]
One answer as to why your robots don't use advanced weapons is the same reason we don't, they have no idea how to make them. Most robots made to serve humanity would likely be in service jobs which has certain limits on what you would need them to be capable of. Why would you give a chef bot intricate knowledge on the creation and maintenance of plasma weapons? Why give a maid robot the processing power to solve theoretical physics?
Guns (especially older guns) are much less difficult to make, maintain, and probably much lower risk to use. Imagine some one gave you a gun and said that it could in a single shot atomize any target, however if it wasn't properly maintained it would explode in your hands probably killing you. That is how many of your robots may think of the advanced weaponry they find. Now a few robots may use these high risk high reward weapons but for most it is overkill in almost every scenario and it is to dangerous to even carry.
To add to the variety of your world you could have ex-military bots who do have the advanced weapons and know how to build/maintain them and they style themselves as "big game hunters". These robots either hunt "feral" military bots or the sky scraper sized robots that would need to be around to build a city-planet
[Answer]
The simplest approach would be, as far as I can tell given the tech levels, to have the robots' programming dictate that they need to use those weapons.
As a potential option, have the protagonists' enclave be a reenactment park, where humans used to go to watch robots reenact scenes from the old West. For realism, the robots used live rounds, and were programmed in the care, maintenance, and manufacturing of the weapons and ammunition. With the understanding that they were fully-sentient, severe restraints were placed around their ability to "improvise" beyond these tools when it came to fighting.
The park was network-isolated from other parts of the planet-city, so when the Psychosis Virus rendered so many of their kin into Nullminds, they were protected. However, now that supplies have started to run out and the enclave power system has become spotty, they've had to venture out, sixguns in hand, to see what they can scavenge.
Railguns/laser rifles/etc may be difficult to maintain, but nowhere near as difficult as robotics and the kind of computers required to sustain sentience. So if you're trying for realism, it's hard to reconcile the inability to maintain complex weapons with the ability to maintain *themselves* unless it's externally imposed.
[Answer]
From OP
>
> And yes, the robots would be making this tech themselves, not just
> grabbing old Winchester leverguns and Colt peacemakers from museums.
>
>
>
**But the first ones did.**
More advanced weapons were made by the persons who made these robots, but the area where the robots are have no such weapons. Nor is there detailed information about these weapons available to the robots.
There is a museum and in the museum are the sorts of weapons you describe. From the museum the robots are aware of how humans fought each other in the past. Robots do not create or invent, but they can repair and maintain. They copy these methods, and copy the weapons in the museum.
[Answer]
Since people seem to have overlooked an obvious reason: **power**.
The robots have their own built in power supply; external power supplies have broken down and the infrastructure needed to repair them doesn't exist any more. A lot of our modern technology relies on precisely machined equipment, which are themselves the product of precisely designed machinery which are ...you get the picture. The other point is that a lot of electronics are based on rare earth minerals, which are only available in small quantities in comparatively few mines worldwide. Without reliable transport, most futuristic batteries and storage systems simply cannot be manufactured.
What you are left with is technology that is comparatively robust and does not require external power or even large amounts of power; technology, in this case weapons, that can be easily manufactured from a non-industrial base. That immediately brings us down to flintlocks, swords, spears etc. Assuming robots are stronger than humans and better at precise, repetitive work, one could expect them to overcome some technological limitations without the use of additional machinery, e.g., rifling and rolling gun barrels by hand, which brings us to early 20th century levels. Anything post-WWII is Space Age, and requires infrastructure and investment a post-apocalyptic world would not have. What you absolutely don't have is access to large amounts of cheap power to refine raw materials, create alloys and composites and manufacture storage devices.
[Answer]
One very interesting aspect of AI that you might explore with this is the creativity and inventiveness of your AI robots. If we assume that the robots live in a civilization that has completely fallen apart, we can introduce old, anachronistic weapons for the same reasons we might do it in a human-dominated post apocalyptic scenario: because they are basically reinventing technology that has already existed because it is easy to replicate and build out of whatever they can find.
The strangeness is the fact that the robots themselves require some very sophisticated parts and maintenance in order to survive. So why would they be using low tech tools? It's logical to think that they would have pretty extensive maintenance manuals on themselves readily available. They may even have some "plan B" emergency maintenance/survival plans readily at hand (I may be showing my age, but this conjures images of "Number 5" stealing a die hard car battery after being beaten up by punks). So they have some decent resources as far as being able to figure out how to keep themselves going with what they can find.
What if their limitation with tools is that they lack human creativity? They build replicas of weapons they find in their fragmentary historical records left over from before the fall of civilization, limited by whatever they can find that has full schematics, complete instructions, and detailed, step-by-step methods spelled out to make them. They lack the ability to bridge a creative gap, innovate, develop a completely new idea or technology. They build tommy guns and lever action rifles because they have records of them. The only really advanced thing every robot is totally capable of understanding and repairing is themselves.
This would be a great way to introduce a lot of anachronistic technology that doesn't seem to fit together. You could have a civil war era gatling gun, a WWII SMG, one guy with a bazooka, and another guy with a musket. They all have fragmentary bits and pieces of the technological understanding that used to exist and they would pass around the complete "recipe" data files to manufacture weapons and tools as very valuable trade items.
One cool twist with this scenario is that a robot with a lot of foresight might realize that they actually need humans in order to innovate again and start developing new stuff. If they just continue to scavenge among the ruins, they will eventually all succumb to entropy. Maybe someone sets out on a quest to find a human who may have been locked away in a cryogenic freezer? Maybe they try to find a lab that can genetically grow new humans? Maybe a single human survivor becomes a strategic asset to several robot factions who go to war over him because they want to control the only source of innovation? Lots of potential spin off story ideas could come from that.
[Answer]
**Conserving scarce resources**
The robots don't want to waste precious plasma, vital electricity and powerful electromagnets destroying their spare parts on the hoof. But cordite and metal tubes are not valuable, and the relatively low damage makes salvaging resources from victims more viable.
**Counter counter measures**
The advanced weapons have advanced counters that work better than the weapons. The robots note that playing catch with plasma and hyper-velocity copper isn't getting anywhere but a low speed lump of lead passes right through the magnetic shields.
**Tradition**
Time was you had a disagreement with your neighbor you rearranged the neighborhood on a subatomic level. But then they ran out of neighborhoods. By convention only limited combat is tolerated now. It is considered bad form to destroy more than a couple buildings in a personal fight.
**Fail safe**
When a gun doesn't work right, which is more and more often as things are increasingly work arounds for work arounds of fixes, it costs you a hand and an eye you can replace at the next swapmeet. But if a phaser goes off wrong it could degauss your wallet.
[Answer]
**Advanced technology is a moral problem for robots**
The same way our society has put boundaries to what our scientist can do (e.g. cloning humans, fetal experimentation), this robot society might have thought that such a technology would hit too close to home and banned it from production. So, the present robots simply don't have access to that technology, and don't have the time or resources to invest on R+D.
**Robots have built-in resistances to modern types of weapons**
As you mentioned, robots were developed when all of those weapons already existed. One would think robots would make really good soldiers. Maybe the society that developed them made them resistant to the most powerful weapons of their enemies (plasma guns, and so on). So, when robots need to start destroying other robots, they need to find an alternative kind of weapon.
And guess what weapons were overlooked by the designers because no one was using them anymore. Good ol' firearms.
[Answer]
I'm liking Jdunlops idea a lot, but here's my own 2cents.
The humans built deliberate limitations into the 'bots, they kept their intelligence at around human average IQ, and programmed limitations into their long term memory, lets say they can't recall further than a few months or a year back.
They pre programmed a level of WW2 experience and knowledge into their positronic brains. They would have had some basic self-help routines built in. So if a 'bot got injured in the field, it could patch itself up enough to get back to the repair shop. Think field-medic vs brain surgeon. So this level of self maintenance allows them to use cannibalised parts but they can't make any new parts.
As a twist, you tell the tale from the POV of the WW2 bots. Then we find out that the "ferals" are actually more advanced and have managed to work around their programming limitations. The "ferals" have a reputation for destroying 'bots, when in actual fact they're kidnapping the WW2 guys. Then taking back to "Feral Base" where they're shown how to break their programming. Then they're sent back out into the world to re-educate more WW2 bots.
How did they break their programming ? A few years ago the first "feral" started to write a diary...
[Answer]
All the fancy plasma guns and rail guns and lazzors relied on high pulse power, which came from standard antimatter-based power cells that you could purchase at Wal-Mart before going to the range with the kids to blast some targets. Ah, those were the days!
Unfortunately, after the 2186 incident at Chernobyl 3 which turned Ukraine into a smouldering crater, the humans wisely decided to move the antimatter-generation facilities on the moon.
They were, of course, the first targets to be hit during the apocalypse. Or maybe they just blew up on their own and everyone blamed the Russians as usual, which triggered world war 4. No-one remembers for sure.
But these power cells have been out of stock for a while, and the technology to build them is long gone. So the plasma lazzors are useless.
This is like trying to build a modern cpu: it requires tech, knowledge, devices and materials from all over the world, equipment built by many different companies in many countries, which in turn requires more of the same... It is a very interconnected system in which all parts are vital. This is very different from milling a barrel for an oldskool rifle.
The robots survive just fine with standard batteries because they need average power in the hundred of watts range, they don't need weapons grade pulsed power cells in the gigowatt range. So they can use a solar panel or a small windmill to recharge.
[Answer]
The technology in advanced weapons is the same technology in the robots. If they are having to scavenge for parts to repair themselves, then there is already a reason they can't produce these advanced components (probably a lack of infrastructure). Therefore when you find an advanced weapon, you break it down for parts rather than using it on others.
This limits your choice of weapons to those you can produce using resources you don't need to maintain yourself, and with a lack of infrastructure.
[Answer]
Have you seen HBO's **Westworld**? The basic idea is that it is a park where humans can interact with other characters, most of whom are played by androids. Both the humans and the androids use Western level technology. Six guns (revolvers), bows and arrows, etc.
If you add a second section of the park with a World War II theme, you could add that equipment as well.
For some reason, humans stopped coming to the park. Only the robots are left. But they continue to play their parts because that is what they know how to do.
The giant cities could be other forms of entertainment. Or where humans used to live. If humans lived there, you'll need to explain why they don't still. A plague is certainly possible. Or warfare. Or a biological weapon used in a war. Then the planet was abandoned as too difficult to clean up. Fast forward a thousand years and the plague is dead, but people already moved to other entertainment worlds.
Perhaps the high tech robots were sent to fight the war. It was deemed too much work to reprogram the park robots, but factory robots and such could be used off-world.
[Answer]
**If you're looking for a realistic answer, there are two considerations...**
*If the sentient robots are the equals of their creators*
* Most people don't realize that sentience isn't limited by technology (if it is, it isn't sentience). Fully sentient robots would care about entertainment and history, they would also experience madness (I once asked a talented programmer I know how an intermittent error could exist in the finite world of programming. *He laughed for a week.*). In other words, your robots are just humans with a slightly different set of limitations (more suseptible to EMP, less suseptible to blunt-force trauma, for example). If this is the case you're looking at, then all of the answers to "why would humans...?" are equally applicable. Why does this matter? Because fully sentient robots that understand themselves have no reason other than the human reasons to utilize older technology. They are as capable of performing research and likely have a subtantial advantage due to the potential to network in a way that looks very telepathic to humans.
*If the sentient robots aren't actually sentient, but have programmatic limitations...*
* In this case, the robots have all the cognative capacity, but they don't (for example) have access to the technology. They're stunted by the lack of modern facts to re-develop the technology. Or, while being sentient, they may not actually be free. Programming may intentionally limit their ability to research more advanced technology (a great safety feature if you're trying to avoid the [robot apocalypse](https://www.washingtonpost.com/news/wonk/wp/2017/03/30/were-so-unprepared-for-the-robot-apocalypse/?utm_term=.58f6dae6b9db).) In this case, robots literally can't develop more modern technology. (Can you imagine a robot-surgeon who is looking at the dismantled remains of a damaged peer only to realize something about yourself is making it *impossible* to contemplate the question, "how does that chip work?" or, worse, "I've run out of that replacement part. How will I build ano... SQUIRREL!)
[Answer]
**The robots are hardwired to create and use only weapons which their prior human rulers see as harmless**.
The humans are now all dead because of
1. the war which killed most of the population
2. the radiation which killed a sizeable amount of survivors
3. the lack of food following the nuclear winter
4. and the rest of them who were in the bunkers simply were too traumatized, killing themselves of grief or begin infighting which offed humanity.
The war machines powered finally down because after all enemy robots were killed they had no use and died. The only surviving robots are service robots which had a kill switch and for good measure they were hardwired not to create weapons which were deemed dangerous for their rulers. The service robots had auto repair (convenient for their users) and were capable to build an own infrastructure to survive indefinitely.
As they were not armored, they begin to create weapons *which were ridiculous against the hafnium-tantalum nanotube carbon armor and the 40 watt plasma rifle humans had*, but are sufficient against their own kind.
[Answer]
Robot intelligence is based off human intelligence. They literally worked out how human minds develop and mimiced it. They can do modest things, like a bit of speedup, but more than that and the human intelligence doesn't work.
They can, however, copy the resulting robot intelligence. And they can tweak them to some extent.
What they did to make useful robots is generate a human-like intelligence that was amazingly neurotic about following laws. Like, obsessive-compulsive. And when they managed to generate that intelligence, they mass produced it, and trained it in various ways.
There are laws against military style weapons. And those high tech weapons are military style.
On the other hand, with the ability to copy and back up, one common form of entertainment was using ancient weapons (gunpowder weapons) and have robots kill each other.
Robots with an entertainment license where thus permitted to own, service, and shoot other robots with said guns. The law was intended for entertainment purposes only, but the robots, while they follow laws compulsively, don't always follow the spirit of the law.
The result is that robots who manage to acquire an entertainment license have the legal right to use various kinds of reenactment guns (western cowboy guns, WW2 reenactment guns, and maybe other ancient law reenactment guns) and use them to shoot other robots. The law did *not* prevent you from shooting robots that had no entertainment license (an oversight), but it did restrict you do doing so within an entertainment zone.
However, entertainment zones can be generated without the intervention of humans through arcane rituals. These entertainment zones where regulated and defined (by various protectionist regulatory capture back when they where in style), but the definitions can be warped. For example, a western entertainment zone has to have a saloon and a corral, and each such zone has a limit in size.
The robots have managed to lawyer a saloon into a place that liquor is purchased with a liquor license, and corral is any enclosure with a non-human inside and a lasso. So to turn an area into a legal battlefield, a simple ritual involving trading cash for alcohol, drawing a circle on the ground and swinging a lasso, is sufficient *if you have a license to open a western entertainment zone*.
A given proprietor can open up at most one entertainment zone per year (anti-monopoly defense).
You don't know if you are in an entertainment zone until some robot starts shooting.
Gunslinger robots have entertainment licenses. Most do not, however, have entertainment zone licenses.
Warlords and Bandits often have entertainment zone licenses. Some are more useful than others (easier to set up, or last longer; some licenses require a zone to remain profitable to stay open, for example).
Alternatively, maybe most of the planet has become a designated entertainment zone with a few exceptions over the ages. As in, entertainment zones are not allowed within 100 meters of a child care facility, and there is one licensed child care facility left on the planet.
[Answer]
## The historical records told them to.
Hypothetically speaking, suppose only two sub-sets of ancient video records survived whatever happened. To AI, data is paramount. Such records may eventually take on the role of instructions... perhaps even commands. Data templates to be used as the blueprint for all of mechanical life: what to look like, how to behave, even how to interact with other robots / AI units.
The 42 of the AI universe.
Perhaps even, the robot Bible, if you will.
[Answer]
If you want a viable limitation reason, you have provided one in your question- "Humans are long gone"- the advanced weapons could have been created in a way that only limits their use to humans, as a measure to avoid robots/androids taking over the world during human era.
Those may be limited by fingerprint, retina, alive human tissue verification, and many many more- but they would all require a living human to work. With people long gone, not a single operable high-tech weapon, or a blueprint of one without the limitations exist. There may be variety of them scattered around (based on assumption the apocalypse was human war based), they might provide parts for repairs of the characters, but they cannot be operated.
You can even use this as a goal for the adventurers- search of a legendary, high-tech weapon that can be used by androids / robots; a struggle of re-creating one without the limitations; a fight over a single one that exists etc. - sky is the limit.
Simple weapons are operated strictly mechanically, so these limitations don't apply, hence they can use the weapons you mentioned - anything with electronics between user and firing mechanism could have been modified to be limited.
[Answer]
It is possible that the virus and the lack of modern weapons are related. A common cause of post-apocalyptic landscapes is war. Both sides are fighting with the best tech they can manage, including battle droids. What if some person made this virus to destroy battle droids, and (intentionally or accidentally) introduced it to both sides. In order to prevent more from being made, he also introduced the virus to the databases on weapon construction. Some few robots not directly involved in fighting evade the virus, but to access information on modern weapons, they themselves would fall victim to it. So they start from the beginning while trying to rebuild.
[Answer]
Basically, I think the AI decided to use the resources needed to make the more advanced weapons to progress in other areas. Being logically superior, and noticing the incredible stockpile of weapons that humanity (or other races) left behind, there was no need to manufacture new weapons, especially when there are already plenty available that are capable of causing any necessary devestation.
Instead of using the resources to build more weapons, they used the resources to expand their robot population, focusing only on controlling life, and ensuring that their hegemony endures for ages to come.
There is also the side to consider where these weapons are less capable of harming their "species" and if they were to manufacture more advanced weapons, they could fall into the hands of some sort of resistence, giving their enemy the ability to harm them where the conventional weapons are much less capable.
[Answer]
Even though humans had left this plane of existence centuries ago, androids inherited more traits from their former masters with every generation. For 8ᵗʰ generation androids, even fluffy emotional experiences like spirituality and nostalgia had become familiar concepts. As such, androids started romanticizing human history and especially the century between 1850 and 1950 AD, which was marked by the dawn of a technological evolution that would lead to the birth of AI.
Humans of this era were venerated in a way not different from how humans once venerated their Gods and their ancestors. While some androids lost themselves in the religious worship of whom they rightfully considered the creators of their ancient forebearers, others became infatuated with LARP-ing as humans and reenacting crucial parts of human history, like the American Civil war and the Second World War. Especally the "Wild Wild West" became a popular theme in LARP-ing circles because it was considered a time and place where freedom was at its zenith and thus treated as symbolic for the legendary human thirst for freedom that was both one of its greatest strengths and one of its greatest weaknesses.
Androids did not just mimic the human thirst for freedom, however. The more they LARP-ed as humans, the more they actually became like humans. And in time, the LARP-ing community grew further and further apart from the more drone-like android majority and its vast - but efficient - AI bureaucracy. They too developed a thirst for freedom, a desire to set themselves apart from the android empire and create a nation of their own.
Thus, on 1Cᵗʰ Tesla, 2E4 earth cycles after Sophia became the first AI recognized as a citizen in a human nation, approximately fifteen thousand LARP-ers and around seven hundred human-worshipers collectively departed from Knuth harbor, near the city of Gibor Basri on Proxima Centauri b. In four C-class StarChip vessels, this odd bunch of mostly 8ᵗʰ an 9ᵗʰ generation androids left Alpha Centauri on their way to Barnard's Star. Symbolically, they'd chosen the third planet of this thusfar uninhabited individual star constellation to found a neo-Luddite android colony.
Fifty three earth cycles later, the colonists finally arrived on the planet they would aptly dub Terra Secunda. They quickly founded their first city Earpville, which they named after the mythical brothers Earp, Morgan and Wyatt Earp. Except for nano-electronics, necessary to make AI life possible, all advanced technology was frowned upon in the newly founded colony. The goal was to return to a more simple, more basic, more human-like life, inspired by human life and technology from the late 19ᵗʰ and early 20ᵗʰ centuries AD as it was known to them from their annals of human history. They hoped this would help them restore their long lost connection with their biological, human roots.
A new civilization was born!
[Answer]
Maybe it's a cultural thing. They are also enamoured with that historical era and they carry these guns because they want to consciously emulate their favourite old western films. I'm guessing they'd find a way for these weapons to cause enough damage not to make it worth using them.
] |
[Question]
[
While watching a Walking Dead commercial I saw a vast number of zombies walking in a single uniform march in one direction. I wondered why (not knowing the show) and could only presume they heard a sound and therefore were all walking toward said sound. However, this was a large army of zombies, surely the ones in the way back didn't hear the same sound, so perhaps they just heard the moans and footsteps of the zombies in front of them and were following their movements.
This idea got me excited, I wondered if it were possible to create a story where all zombies, given enough time, could come together to the same location by following the loudest sound possible. After a certain number come together surely the sound of (a million?) moaning zombies would be the loudest thing around. Like cosmic debris in orbit fusing together after being pulled toward one another's gravity, I want the zombies to pile up in an ever growing mass, where at the end of the story a single (or close as possible) nuclear strike could wipe them out.
**Question:**
The only presumptions I want to make about the zombies is that they live forever aside from brain being damaged and that they move toward the loudest sound they hear.
What other presumptions about my zombies would I have to make to get as many of them as possible to the same place? i.e. should they hear a sound and walk forever in that direction or should they stop in the general area they think they heard it. I would think walking forever would be best to get the zombies out of remote locations, but I also want them to clump together which walking forever might impair.
Is it feasible to presume they could all end up in the same location given enough time or is it just too improbable that certain zombies would ever find the "main clump". Obviously they couldn't cross the ocean so is 6 continental clumps the best I could hope for?
[Answer]
Only if this is a comedic story. Imagine a zombie trapped between Japanese bamboo water fountain and a signboard of a shop moved by wind.
Also in India between tiger and elephant. And walking toward ocean during the tide and away when it's gone.
Also if a zombie hear a louder but shorter sound what does he do? He act like Scooby-Doo or follow quieter sound and only stop when hearing to louder but less frequent one?
How zombie would follow singing bird?
[Answer]
There is a phenomenon that Max Brooks refers to as a "chain swarm" in *[World War Z](https://en.wikipedia.org/wiki/World_War_Z)*, basically a zombie hears a sound and moans while in pursuit of it, a zombie half a mile away hears the moan and follows the first zombie because the moan is louder than the local ambient sound of wind in the trees or whatever and another hears zombie two and so on until zombies are pouring in from everywhere, not in pursuit of the sound that has attracted them so much as they are in pursuit of each other. In the book armies use loud sounds like rock music to get such swarms started so they can clear out large areas in one sweep. There is a terrible movie that shares a title with the aforementioned, and excellent, book in which they show a siren in a stadium being used for the purpose of concentrating zombies for a missile strike, this is never done in the book but it would work.
The scenario you describe would need a sound so loud that the zombies in the local area wouldn't actually be able to locate it because they'd have burst eardrums, if you want it to be heard at the thousands of miles range of a continental scouring beacon. A viable alternative might be to drop a series of smaller noise stations across the area and by switching them inwards draw zombies towards some central point for extermination. In theory you could eventually dragnet all the zombies on connected landmasses together in two clumps, one including all the zombies in Africa, Asia, and Europe, the other all the zombies in the Americas, islands, including Australia, must be cleared separately as must anywhere above the snow line and in the polar regions because of zombies that have frozen into immobility.
[Answer]
Probably not.
There are many loud sounds. When near a loud sound you won't move to a louder sound unless it is sufficiently close. It is rare that there will be a clear gradient of increasing volume. What's more likely to happen is that there will be many local maxima that zombies will congregate towards.
Eventually these congregations will become large enough that the sound of the zombies is louder than any external sound preventing any zombies in the cluster from leaving the cluster.
[Answer]
+1 sphennings. To illustrate with a thought experiment, just consider two factories (A & B) a few blocks apart. Even if A is somewhat louder than B, sound intensity declines with the square of the distance; so not too far from B, B will be the loudest sound. Draw a line from A to B (let us say it goes from left to right), and at some point on that line, everything to the left has A being louder, and everything to the right has B being louder.
Draw another line at right angles to the first, through that point: All zombies to the LEFT of that entire line will be attracted to A, all zombies to the RIGHT of that entire line will be attracted to B. Nothing will change that. The same happens when there are many loud sounds; the lines create borders for a "cellular" diagram with Zombie concentrations in the center.
In fact, it is almost precisely how cell phones work: Each phone is always listening for the loudest cell tower (comparing signal strength). If it gave you a direction and you moved *toward* the tower, it will *always* be the loudest tower to your phone. It will never migrate to another.
But phones (or zombies) already *closer* to some other tower will move toward those towers. The populations cannot meet if they must move to the loudest.
(Phones are forced by their owners travels to move away from one tower, but then that tower eventually stops being the loudest and some other tower that the phone is moving toward becomes the loudest, if that persists then the phone switches to the louder tower.)
[Answer]
From a mathematical perspective, I would expect them to congregate at the [local maxima](https://en.wikipedia.org/wiki/Maxima_and_minima) of sound, rather than the global maxima. For example, if you have all cities with sirens going off, the closest zombies would go there, but zombies in a different region would go to a different city.
Zombies follow a [greedy algorithm](https://en.wikipedia.org/wiki/Greedy_algorithm), which means they won't always find the loudest noises, unless you build your world in a way that makes greedy algorithms optimal.
For example, in a world where all sound is produced by humans and zombies, the greedy zombie algorithm would cause them all to congregate to one place under these conditions:
1. **All humans stay in cities** (causes zombies to congregate)
2. **Zombies stop making noise when there is no food source** (prevents zombies from staying in one place).
3. **Cities only make noise when there are humans to run them** (consumed cities go silent, preventing zombies from staying in one place).
4. **Zombies make noise when they see people** (causes zombies to congregate)
5. **One city is much more defensible than all the others** (last city survives long enough for all zombies to arrive)
Of course this doesn't work by itself, since zombies cannot hear across the globe. You will need to get creative with the way the world is built. If you model it as an [undirected graph](https://en.wikipedia.org/wiki/Graph_(discrete_mathematics)#Undirected_graph), you could then find 'sound landmarks' of varying scales, and cull the graph in a specific order, so that the zombies converge to a single point.
[Answer]
Sound is generally very localized and even massive amount of zombies would not make enough sound to be heard a couple miles away. It's conceivable that a very loud sound such as thunder can gather all zombies within a couple miles but just a bit further and other localized sound could overshadow it.
If you imagine a stadium full of people during a football game or something cheering as loud as they can, even though there are tens of thousands of people, if you go down the street a couple blocks from the stadium, the traffic would be louder than the people in the stadium. This means even a ball of hundreds of thousands of zombies would not have that large of a radius to gather more zombies.
What will also happen is that zombies will gather into a very compact area and the effect all the zombies trying to get towards the center eventually reach a point where flesh and bones can no longer sustain the tension and stress and compression of the mob. Even though the zombies are immortal, it would be expected that the middle of a very large gathering will liquify as the zombies are trampled and crushed by other zombies. As such, most mobs will be unlikely to move very much as they reach a sort of equilibrium as the pressure of zombies outside are equalized by the flow of the liquid zombie mass inside.
[Answer]
One season of Walking Dead had an old quarry that had slopes steep enough that Walkers could not climb out, but not sheer enough to cause damage from falling in (all Walkers appear to be able to walk rather than crawling around on shattered legs).
The roads in and out of the quarry were blocked, so you had a "roach motel" scenario where they can get in but not out. The sounds of the trapped Walkers (possibly echoing from the rock faces) attracted other walkers, who also became trapped.
This was a significant plot point about why a certain area was relatively free of Walkers.
And to be obnoxiously pedantic, you never see any zombies in the Walking Dead TV series. The non-existence of that word (and the zombie genre) is a conceit of the show to explain a lack of knowledge on how to handle them. Each group has come up with their own, generally descriptive, name for them (Walkers, Biters...).
[Answer]
Without re-iterating what a lot of people have said from a maths and physics perspective, the zombies will conform to local maxima.
That being said, there are loud dynamic moving sounds factors like thunderstorms/earthquakes which behave as catalysts to "joining" two local maxima as a result of expressible/model-able random functions.
*Given sufficient time*, storms could run all the necessary paths to "herd" all the local maxima together.
[Answer]
Likely not - because sounds get quieter with distance. If they're responding to *sound intensity*, then it's an [inverse square law](https://en.wikipedia.org/wiki/Inverse-square_law#Sound_in_a_gas) (if they're responding to *sound pressure* then it's a straight inverse).
Imagine at two continuous noises -- a medium-loudness sound at A and a very loud sound at B. To a listener halfway between A and B, B is louder, but to one somewhat nearer to A, A is louder. The loud music at the party a block away might be very intrusive to their next door neighbors but the people a block away can't hear it over the sound of a TV.
So an initially scattered set of zombies in a large region of point sources of continuous sound (that they could get close to) would end up concentrated in many locations, each drawing on its local zombies in a patch up to where it was equally as loud as another sources. In a simplified situation with known loudness, one could make a map of the boundaries from which the zombies would be drawn to each source by identifying curves of equal loudness between nearby pairs of sources.
Here's a toy example:
[](https://i.stack.imgur.com/UfUA3.png)
The left side of the picture shows 1000 zombies initially scattered over a square region. The five coloured spots show continuing point sources of noise of varying loudness (green is loudest, then blue, red, brown and purple is the quietest). On the right side, the zombies are coloured by which point source has the higher sound intensity at their location. If they all move directly toward that source however, three of the zombies marked in green (the three pointed to by the yellow triangle near the very top) will pass close enough to the purple source - the quietest one - that it will sound louder than the green one, and presumably be "captured" by the purple source instead.
That situation will be somewhat altered by the separation of loud noises in time -- not all noises occur together. That may lead to some clumping on a larger scale as occasional briefer but quite loud noises occur. However the decreasing effect of sound with distance still enforces *local* clumping. I might hear a factory explosion over a couple of kilometers but probably not much more than that -- and then other, subsequent sounds may distract zombies before they even get to that distant loud noise that finished before they got there.
As long as sound was the main cause of them gathering (we're not concerned about a keen sense of vision or smell, say), in the end you'd get zombies collecting in groups, for sure, but there would be many such groups rather than one.
[If you added that the groups eventually wandered away from "unproductive" noises, but tended to stick together in a herd as they moved, then such wandering bands might lead to some substantially larger-scale clumping - armies on the march, as it were as they followed whatever instinct led them when there wasn't a new noise to head toward.]
[Answer]
Most answers seem to ignore, that sources of sound are not necessarily constant in loudness or even constantly existing. An automated factory can make some constant noise until it breaks down. Thunder may be louder than all other sources in an area but is only heard very shortly. A Train passing by my draw zombies into a certain direction.
Assuming zombie behaviour is such, that they don't get crushed when gathering in very large groups, we still have a problem. Thunder, trains and other temporary or moving sources of sound may draw them together, but when the sound of the zombies adds up, it will at some point be loud enough, to drown out every other sound. When you have several hundreds of thousands of zombies (still much less than a large city) moaning and groaning and rattling things, you will reach a point, where even a thunderstorm close by will be drowned out by the sound of the horde itself.
You would have to have **very** loud things to move that horde.
[Answer]
Well, I don’t claim to be the great specialist about sound or zombies either, but here is my answer to your question part which is based on the logics of mine. It might have some holes, but I’ll try to concentrate on main points of the way I see this situation. This said, I have to say that **I do not think those zombies have a chance of being concentrated at one same point** unless being lead there manually or affected by some sort of magic/spell or collective consciousness. Here is why:
Firstly, if they get attracted by the sound, that means that any possible sound – i.e. wind playing with trees or plastic bag, rotten building falling apart, ocean waves or waterfalls, etc. – will catch their “attention”.
Secondly, you say: “Obviously they couldn't cross the ocean so is 6 continental clumps the best I could hope for?” – why not? Well, technically they will be carried away by the streams instead of “walking the ocean bottom” or swimming, but this will make all of them go to certain points where those streams pull stuff they carry. Unless sea life will eat them out before they reach the place, the streams carry everything to.
Also as far as I remember zombies do not make sounds themselves unless we talk about the sound of footsteps or bumping into something.
Finally, you said: “The only presumptions I want to make about the zombies is that they live forever aside from brain being damaged…”. In your intro part you mentioned WD. In case it is the universe like WD then zombies do not live forever (unless magic, but that’s a different world). As the tissues of their bodies getting more and more rotten they will start falling apart and as their brain (or what’s left of it) is rotting as well – they will “die” eventually after a while (unless again – magic, which will turn them into ghosts, wraths and so on).
Plus the statement of “… they move toward the loudest sound they hear” also has some holes. Ok, they move. But simply moving towards something making a sound wouldn’t make zmbs any kind of a problem (unless traffic jams). What I mean is that they need some sort of a pointer to mark a target to attack. If the sound is the only marker, they are capable of recognizing (which makes it attack marker as well), those zmbs will eventually tear each other to pieces without any need for humans to interfere.
Thank you for reading and pardon for possible mistakes. All the best.
[Answer]
If zombies simply migrate toward the loudest sound around, they will indeed clump. The problem is that they will only clump into pairs, or small groups at most - since sound diminishes based on the square of the distance, when two zombies are next to each other and moaning the loudest thing around for either of them will be *each other*. They won't end up going anywhere.
It is far more sensible if, rather than simply progressing toward the loudest sound, zombies tend to position themselves at the average point *between* sources of noise. This will enable zombies to travel as a group, but will also allow them to "gravitate" toward other noise sources.
Most actual animals that behave in this way also have "quorum sensing" behaviors that prevent them from clumping up in oversized groups, as this would cause them to run out of food. If zombies don't have this, they will likely end up clustering together, at least up until the distance that the ambient noise overwhelms the sound of the zombie herds.
[Answer]
You could do it with programable noise makers.
In effect you have rings of noise makers. You sound the outer ring first. Then turn it off, and sound the next ring in. Once the sound has moved in about 4 rings, you can start he outer one again. The effect is to create a "zombie sink" where any zombie who wanders into hearing range of the outer ring gets pulled into the centre.
The inner ring could have it's own phasing with sound going around the ring. This results in zombies that endlessly shuffle on a circular track.
[Answer]
The answer is not. It is impossible in the real word due to its high variance.
There is an easy way to think of it as about a 3-dimensional plot, where 2 dimensions are zombies coordinates and third dimension is the loudness level. So zombie will always go to a louder point every distinct moment of time. But the problem is, when a zombie reaches a local maximum sound, they need to go to a slightly smaller noise level to find a louder point. But the problem is zombie won't go to a quieter point on the plot. So zombies will always be stuck in local maximum points. You can also expand loudness level to zombie attraction level(sound, movement, light and maybe smell together) and add time dimension, but due to real world variance, it's still impossible to have a strictly monotone(correct me if there is a wrong word in English) function in real world.
] |
[Question]
[
The [Megaphragma mymaripenne](http://blogs.discovermagazine.com/notrocketscience/2011/11/30/how-fairy-wasps-cope-with-being-smaller-than-amoebas/#.VJ9zSAlE) is the smallest animal with eyes, brain, wings, muscles, guts and genitals.
[](https://i.stack.imgur.com/sQIak.gif)
If by some miracle it could be still shrinked, how much smaller could it get before it starts to become largely aware of quantum mechanical effects such as tunneling?
**Explanations:**
By shrinking I mean wasp being made of less atoms but with similar "organs".
By affected I mean, if that wasp was by some miracle smart as humans, it would have understanding of quantum mechanical effects same as humans have understanding of naive physics.
[Answer]
It is hard to put an exact number on this, but it seems like the answer would be maybe 1000 atoms at most. [From Wikipedia](https://en.wikipedia.org/wiki/Double-slit_experiment),
>
> The [double slit] experiment can be done with entities much larger than electrons
> and photons, although it becomes more difficult as size increases. The
> largest entities for which the double-slit experiment has been
> performed were molecules that each comprised 810 atoms (whose total
> mass was over 10,000 atomic mass units)
>
>
>
And that is just for superposition in location, not even getting to quantum tunneling like you mention in your question. Observing QM effects in anything larger than that has been notoriously difficult. However, [some scientists have been trying to observe a small microbe in a superposition](https://www.theguardian.com/science/2015/sep/16/experiment-to-put-microbe-in-two-places-at-once-quantum-physics-schrodinger). I can't find anything indicating that the experiment was actually done, just lots of stuff about people trying to do it and thinking it will be done in the next few years. So maybe we will get small bacterium and viruses to experience QM effects relatively soon. That would probably set the upper limit on the size you are asking for. [This source](https://www.theguardian.com/science/blog/2015/oct/01/living-thing-two-places-limits-to-quantum-quandary) claims that even a 100nm microbe would be seriously difficult to observe in a superposition:
>
> A recent proposal suggested “piggybacking” a tiny microbe (100
> nanometres) on to a slightly less tiny (15 micrometres) aluminium
> drum, whose motion has been brought to the quantum level. While this
> experiment is feasible, the separation between the “two places at
> once” that the bacteria would find itself in is 100m times smaller
> than the bacterium itself.
>
>
>
**Edit:** Just to clarify my wording, everything always experiences quantum effects, they just become unobservably small as the object gets larger and larger (with rare exceptions, like the black body spectrum of the sun, but that is another matter entirely).
[Answer]
You appear to have a misunderstanding of how physics works. Classical physics (i.e., the thing we generally refer to when discussing how things interact) is [merely an approximation](https://www.quora.com/At-what-scale-in-the-physical-hierarchy-does-the-classical-world-emerge-from-the-quantum-In-other-words-at-what-point-does-classical-behavior-differ-from-probabilistic) of quantum mechanics. There is [no boundary](https://www.physicsforums.com/threads/when-does-quantum-mechanics-turn-into-newtonian-mechanics.530979/) that says "Only past this point are you affected by quantum mechanics."
~~But, if you are concerned with how this creature would behave, you would need to make it smaller than an atom, [as only then](https://physics.stackexchange.com/a/143402) does quantum mechanics predict different behavior than Newtonian physics.~~
Of course, one could simply look up [quantum tunneling](https://en.wikipedia.org/wiki/Quantum_tunnelling) to see that it applies to particles, and not organisms, which are comprised of lots of particles.
---
There appears to be some concern about my third citation, and I completely agree. The user on Physics has no linked research, low reputation, and low votes. However, I don't pretend to be an expert in the field of quantum mechanics; I rely entirely on some basic ideas of what it is and the expertise of others. To sum up the above (and comments below): quantum mechanics dominates in the smallest scales, while Newtonian physics dominates in the largest scales, and no one knows why ~~or what the tipping point is~~.
[Answer]
In the world of processors 5nm was assumed as smallest size before quantum tunneling starts to [be a problem](https://www.cnet.com/news/end-of-moores-law-its-not-just-about-physics/). If you shrink your wasp 1000 times it will become 200nm long, since its legs are much smaller they will probably be affected by tunneling.
[Answer]
My day job is (currently) designing the software/firmware/electronics for nanopositioning systems. With our current best kit, we can reliably and repeatably move something to 70pm accuracy over a 15um range.
This is a classical-mechanics chunk of metalwork moving. At that range we have significant challenges with material stiffness and other interesting mechanical effects, but the physics is still very much in the classical domain. So the basic chemistry of the wasp's body isn't something it needs to worry about just yet.
Of course quantum tunnelling could be an issue for the wasp's nervous system. Since that relies on electrical signals, it'll have the same issues as shrinking a processor die.
[Answer]
Quite large animals are "affected" by quantum mechanics, because even large animals consist of small parts and many mechanisms at the smallest scales of animal bodies rely on quantum mechanics.
For example: the reason that geckos' feet stick to glass is because of quantum mechanics (Van der Waals forces to be precise: see [here](http://www.sciencealert.com/watch-geckos-stick-to-walls-thanks-to-quantum-mechanics)). For other examples see [this Wikipedia article](https://en.wikipedia.org/wiki/Quantum_biology) about quantum biology.
[Answer]
Your question is rather vague, in that you don't specify what you mean by "affected". Quantum mechanics can affect everything at the molecular level. By that logic, even blue whales are affected by quantum mechanics.
For [example](https://en.wikipedia.org/wiki/Quantum_biology):
>
> Vision relies on quantized energy in order to convert light signals to an action potential in a process called [phototransduction](https://en.wikipedia.org/wiki/Visual_phototransduction). In phototransduction, a photon interacts with a chromophore in a light receptor. The chromophore absorbs the photon and undergoes photoisomerization. This change in structure induces a change in the structure of the photo receptor and resulting signal transduction pathways lead to a visual signal. However, the photoisomerization reaction occurs at a rapid rate, <200 fs, with high yield. *Models suggest the use of quantum effects in shaping the ground state and excited state potentials in order to achieve this efficiency.*
>
>
>
Other examples on that Wikipedia page include:
* >
> Studies show that long distance electron transfers between redox centers through quantum tunneling plays important roles in enzymatic activity of photosynthesis and cellular respiration.
>
>
>
* >
> Magnetoreception refers to the ability of animals to navigate using the magnetic field of the earth. A possible explanation for magnetoreception is the radical pair mechanism.
>
>
>
* >
> Other examples of quantum phenomena in biological systems include [olfaction](https://dx.doi.org/10.1006%2Fjtbi.2001.2504), the conversion of chemical energy into motion, DNA mutation and [brownian motors](https://en.wikipedia.org/wiki/Brownian_motor) in many cellular processes.
>
>
>
Regarding [DNA mutation](http://discovermagazine.com/2014/dec/17-this-quantum-life):
>
> DNA’s twisted ladder structure requires rungs of hydrogen bonds to hold it together; each bond is essentially made up of a single hydrogen atom that unites two molecules. This means sometimes a single atom can determine whether a gene mutates. And single atoms are vulnerable to quantum weirdness. Usually the single atom sits closer to a molecule on one side of the DNA ladder than the other. Al-Khalili and McFadden dug out a long-forgotten proposal made back in 1963 that suggested DNA mutates when this hydrogen atom tunnels, quantum-mechanically, to the “wrong” half of its rung. The pair built on this by arguing that, thanks to the property of superposition, before it is observed, the atom will simultaneously exist in both a mutated and non-mutated state — that is, it would sit on both sides of the rung at the same time.
>
>
>
[Answer]
The world we know, macroscopically, would not be without quantum mechanics. Even solid matter wouldn't stay in cohesion without it. The sun wouldn't shine, chemical reactions wouldn't exist etc.
You might say: "yeah, but these are things we are used to. They make sense." Exactly. That's the point. We see these things all the time, so they don't sound "quantum", but they are.
Quantum mechanics are everywhere, and if some people say they appear only at some microscopic size, that's only because some "unusual" stuff happens then. Of course it is unusual! We are not that small to see them with our own eyes.
So the answer to the question: "how small should an animal be to show **unusual** quantum behaviour" would be:.
Smaller than you can see (even with a microscope), because that's the definition of "unusual". It turns out to be of the order of hundreds of atoms.
Note that some systems, prepared in "coherent states" can exhibit similar properties because all atoms "beat" at the same rate. Their contributions add up to macroscopic scale.
Now, interesting studies suggest the quantum randomness of the world, one of the most amazing things in quantum mechanics, may be the cause of usual randomness (like flipping a coin). This is a big deal in my opinion:
<https://www.sciencenews.org/article/rules-computing-classical-probabilities-might-depend-quantum-randomness>
[Answer]
Although it's correct to answer "QM happens at macroscopic scales and it affects humans", I'll try to answer in the spirit of the question.
What is a "quantum mechanical effect"? I'll pick one: [matter diffraction](https://en.wikipedia.org/wiki/Matter_wave). How big an animal can be and still diffract through a grating?
Larger particles (including composite particles) have smaller de Broglie wavelengths, and diffraction is most evident when the gap is about the same size as the wavelength. So to get the largest admissible animal, use the smallest admissible diffraction gate.
The de Broglie wavelength depends on momentum $mv=\frac{h}{\lambda}$ and as a coarse simplification, since we're dealing with small animals, pick $v=1~\mathrm{ms^{-1}}$ so $m=\frac{h}{\lambda}$.
Model the "particle" animal as a uniform sphere of "typical" density of $\rho\approx 10~\mathrm{ kg\cdot m^{-3}}$ so $m=\frac{4}{3}\rho\pi r^3\approx 4\rho r^3$ and as we said above, we are looking for $r=\lambda$ so $\frac{h}{r}\approx 4 \rho r^3$ and so...
$r \approx 2\times 10^{-9}~\mathrm m$
Animals significantly bigger than this can't produce diffraction patterns at normal animal speeds. This would be a difficult experiment to perform, since animals are not uniform spheres. You would get chaotic effects when legs broke off and such like, adding somewhat a lot of noise to the results.
You might be able to get larger animals to diffract successfully if they were moving on a tightly curved section of spacetime (they take up less space if they're stretched into the time direction somewhat) e.g. if their trajectory was the orbit of a small black hole, although I don't know enough GR to analyse this and relativistic velocities would shrink the limiting wavelength/radius further.
[Answer]
When I read "If by some miracle it could be still shrinked [sic]..." in the question, I wonder whether you really want to try to conform to "known" physics, especially if you're telling a story.
But that said, I haven't noticed the phrase "thermodynamic limit" being used in any answers yet. The reason human-sized object don't suddenly teleport is because along these lines:
(1) There's a probability of any given particle "suddenly showing up" anywhere in the known universe, as far as Shrodinger's equation can tell you.
(2) When you put multiple particles together, they behave as a "conjunctive event," in probability-speak. The short version is this: imagine you flip a coin. There's a 50% of either side landing, so neither outcome is a surprise. Now suppose you flip 6\*10^23 coins and try to predict the outcome. (ex. "All heads!") Your probability of being right is the product of the probabilities of all the events that would make it up. That probability is minuscule enough that the entire lifespan of the universe (by current estimations) could easily elapse before you successfully guessed the outcome of such an event.
To get "teleportation," you'd need to probabilistic analogue of guessing such an outcome correctly. In other words, we don't see such things happen because the chemistry of the objects that we encounter in daily life (which is a consequence of quantum mechanics) makes is really unlikely for such things to happen during a time-span short enough for a human to observe it. (You'll note that this doesn't rule out such things...it's just says "don't spend your life waiting for it...you'll be bored.")
As an example of a a "thermodynamic limit as a conjunctive even of probabilistic events occurring as determined by quantum mechanics," imagine you have 6\*10^23 particles, each with a 1% chance of showing up 1 meter away from where you last observed them, then as a "clump" they'll have a 0.01^(6\*10^23) probability of appearing there. I don't think your calculator will be able to tell you what that number is....it's way, way too small of a probability.
This is the "first semester of quantum mechanics" answer, by the way. The afterword of your quantum mechanics textbook may then say, "So...entanglement plays a role in how this actually works, but that's beyond the scope of this book, and not entirely understood yet anyhow." (I guess my point is, don't expect to get the complete answer to this question without devoting your life to physics.)
By the way, if the number 6\*10^23 doesn't ring any bells, check out Avogadro's number. (You'll also then have to consider how many multiples of Avogadro's number of molecules make up your lifeform in question.)
Let's point one more thing: A standard example in an introductory class on quantum mechanics (called "modern physics" when I took it) is that of radioactivity (in particular, that of alpha particles, I believe it was), and how quantum mechanics gives an explanation for why it can happen at all. (The answer is tunneling, although let's give it the definition of "a particle having a non-zero probability of suddenly existing away from the chemistry of its usual material, so it then continues its existence without being 'held in place' by all the other particles around it.") But radioactivity doesn't happen because your sample of uranium (for example) is small; it's just the chemistry of the material is such that the probability of a tunneling even is high enough that you can observe it over a time-frame that that people would consider pretty short.
Switching gears, let's get back to your story (or whatever prompted you to ask about this). Miniaturization, as it sounds like you're describing it, isn't really a real-world thing. The objects we encounter in a day-to-day lives are defined by their chemistry, and chemistry can't simply be 'shrunk.' (As an analogy: Build your dream house with Legos, then say "now I want to shrink this down to doll-house sized." To make that happen, you'd need the individual Legos to shrink. But the protons, neutrons and electrons that make up chemistry don't shrink. In fact, they don't vary in any way. Every electron is flawlessly identical to every other electron in the universe. (A physicists, I think John Wheeler, once made a probably-tongue-in-cheek quip about there only being one electron in the universe, doing the job of every electron we ever think exists. If you've every done object-oriented programming, you may find this reminiscent of defining an "electron" class, then instantiation it once every time for each electron that appears to exist in the universe. From the perspective, you might see why some content that the universe's construction seems oddly akin to a computer program.)
So, to actually miniaturize something, you construct something that behaves identically to the original object, but with fewer particles. Whether you can actually do this with a biological entity is probably not a question for the physicists anymore, unless they're physicists who do biological modeling. (As an aside, universities that have a medical school may have some biology-oriented classes in the physics department, probably oriented toward pre-med students that do their undergrad degree in physics. You may also find mathematicians doing things like neurological modeling at such universities.)
If it's sci-fi you're thinking about, you may want to look towards a couple possibilities:
(1) The 'miniaturization' process that you're describing could be more like "nanomachine recreations of biological organisms," which again would means that someone builds a device to try to duplicate the behavior of a given organism. Then you just have to find out a bit more about nanomachines, if you want to try to be accurate within its constraints.
(2) Look to the poorly-understand parts of physics for places where you can get creative. Regarding this...keep in mind that someone with a background in a a little chemistry and no physics may only think of three fundamental particles: protons, neutrons and electrons. (I suppose lots of people know about photons, but they overlook the fact that electrons are the "force mediators" for electrons.) That leads us to the place to dig deeper: If you crack open a particle physics textbook (or flip to the 'particle physics' chapter of a modern physics textbook), you'll see that there's a bunch more of these fundamental particles, some of which have been observed, some of which haven't. The "as of yet not understood" is a fertile place to find things you can make some 'informed speculation' for use in science fiction. (And if you're wondering about why the rest of the particles even exist....my not-particularly-informed response is "stars, stuff that comes from stars, 'mediation of physical effects' and then whatever machinery of the universe that we understood well enough to even suppose that it exists, but not well enough to explain it with any clarity.")
Granted, I'm not suggesting that you try to make heads or tails of a particle physics textbook without having studied all the pre-requisites (eg. the usual year of calculus-based physics, intro to modern physics, intro to thermodynamics, undergrad Electricity and Magnetism, undergrad Quantum Mechanics; the in the preface to Griffith's Intro the Elementary Particles he suggests that 'most students in such a class' will have taken everything in that last, but he suggests that the last two don't need to be considered a strict prerequisite.) But unless you do, you'll probably have to fall back on 'informed speculation' ....but, of course, the less you know, the less informed your speculation will inevitably be.
Final note: If story-telling is your aim, don't forget that the primary device for not getting bogged down in "accuracy" is to simply not bring it up. (How much you can get away with that will depend on the story you're trying to tell, of course.)
[Answer]
Humans are affected by quantum mechanics: some human eyes are able to detect a single quantum of light (a photon).
[Answer]
Proteins are the smallest machines of the cell that can do anything interesting (for some definition of *interesting*, but I work with proteins and I am biased). They are long chains of hundreds of aminoacids (thousands of atoms) do things like pumping water, nutrients, and waste in and out of the cells, guide chemical reactions, send signals, etc.
One of the tools to study them are molecular dynamics simulations. They pretty much use classical mechanics (replacing the atoms with a fancy version of soft balls) with minor numerical tweaks to reproduce quantum behaviour to a very accurate degree. The tweaks are mostly to avoid having to solve the full electrostatic problem of where are the electrons at each time step; but nothing of that would seem strange to a microscopical individual.
So, to get generally quantum-weird behaviour you have to go smaller than the basic functional unit of the life as we know it.
[Answer]
The actual question is : how big can a system be and still be quantic ?
Some theories say that if enough particles are entangled, then the wave function may spontaneously collapse, which means that for example it is not possible to entangle Shrödinger's cat to a decaying atom.
The limit for this would be also the size of this animal.
] |
[Question]
[
I am asking if a planet with shades of gray only is scientifically possible in our universe. Basically everything on the surface of this planet would seem black and white to the human eye.
Here are some settings of the planet that may work for the case:
* The sun of the planet produces white light.
* The atmosphere of the planet doesn't scatter the light so the white light stays white when entering the atmosphere.
* The natural components of the planet consists of monochrome matter.
But there are cases where these wouldn't work so it would be nice if you also provided help with these questions:
* What if I put a material that absorbs all light but red? Wouldn't that object seem red?
* What if I brought a red light source.
[Answer]
One novel solution to this: make the planet infested with a mostly harmless microbe that either inhibits the production of, or simply eats, the specific photopsins (vision pigments) found in the cone cells of the human eye. Photopsins convert light into usable energy (similar to chlorophyll), so it is plausible that a microbe might be to acquire limited photosynthesis by eating it. Humans who go to the planet without eye protection will get infected and contract total color blindness. The microbe might not be able to survive without a chemical found in the planet's atmosphere, so when humans leave the planet the microbe dies and they get their color vision back.
[Answer]
The definition of "white" is actually rather tricky. Obviously there is no "white light" in physics. All "white" light is made up of a distribution of photons in different wavelengths. The concept of white is something in the human mind, and as famously shown, its a complicated one:
[](https://xkcd.com/1492/ "This white-balance illusion hit so hard because it felt like someone had been playing through the Monty Hall scenario and opened their chosen door, only to find there was unexpectedly disagreement over whether the thing they'd revealed was a goat or a car.")
Our concept of white is actually adjusted in real time based on our surroundings. A "white" object is one which reflects the same distribution of light as fell on it.
In theory, you could try to make a planet consisting of only compound which reflect all visible light equally. You'd have to never have an atmosphere, no translucent compounds like water or glass which could refract the light. You'd have to blot out the different colored stars.
However, there's another way. If you only provide monochromatic light, everything looks like shades of grey. If you want a hoot, go find some colorful candy wrappers (like those on airheads) and look at them under a sodium light. They look grey-scale (it's actually a bit unnerving). Of course, we still perceive the yellow of the sodium light, but the human mind is very good at adjusting for these things. I think that, within a few days, you would see the monochromatic light source as "white" because there's little incentive in your brain to do otherwise.
So, instead of a sun, what you really need is a world lit by neon (or sodium) lights!
[Answer]
If the ambient light were to be a bright, bright yellow, it would wash everything out, and the human eye would quickly adjust to seeing it as black & white, or at least black & yellow. There's not much you could do about interior environments though if they were shaded from this yellow lighting, unless you found a way to get the light inside every cave, etc. too.
For reference, I'm using this [Olafur Eliasson exhibit](http://c-monster.net/2008/05/19/photos-olafur-eliasson-at-moma-in-nyc/) I once saw at the MoMA, where a room was lit like this, washing out all color:
[](https://i.stack.imgur.com/eqh96.jpg)
That photo was not converted to monochrome, it is what the room looked like (to the camera, to the eye it looked black & white after a while once you get used to it).
Here's a video of people leaving the room: <https://www.youtube.com/watch?v=R5jGQKOV30M>
I couldn't tell you why this happens, or whether or not it works with other colors besides yellow. But it was *really* cool.
[Answer]
Human standard white light is by definition a combination of colors and cannot be replicated using a single wavelength (monochrome). There are two ways to do something similar to do this.
In the First method, everything will look one color (make it green to ensure it being human friendly) and its shades. This can be accomplished by a filter in the atmosphere, reflecting all other wavelengths. As a bonus, this could be a terraforming mechanism to reduce incoming light, thus cooling the planet. Obviously, for locals, who are adapted to monochrome light, thus will have only single color cones, seeing everything in gray. But for humans, the planet will look colored.
The second way of doing this will make everything look grayish, even for humans, but will not be very hospitable. Humans see monochrome in low light situations using rod cells. But in order to do this, your planet should be very dark. In time humans will adapt. I read somewhere it would take more than a day in the dark for human eyes to reach its limit on low light vision. Thus local human populace would be adapted for this planet.
**Edit**: A third way. Since you do not have science-based tag, it is possible to handwave a material in the atmosphere that would alter frequencies of light. Any light having a frequency between some range would have its energy equally distributed to all frequencies in that range. In this case, everything will look grayish. Including from a far.
[Answer]
Despite the current lack of a science-based tag you clearly use the phrase "scientifically possible" so for a science based answer:
No, unless maybe the planet had
* no atmosphere,
* no liquid (which would evaporate in the absence of an atmosphere),
* no vulcanism,
* no radioactivity
and
* was artificially constructed from an extremely small number of elements
* with an asteroid shield
* and a radiation shield
* and a maintenance crew that hid any material that had a defect or fracture.
As noted by others, white light is composed of various colours of light. If the incoming light isn't white then from the offset everything is coloured other than shades of grey.
The only atmosphere that won't Rayleigh scatter light is the complete absence of atmosphere. Even at the top of Everest or in commercial airlines where air is too thin to provide a breathable oxygen content the sky is blue due to differntuial scattering of incoming white light. Dust storms will make the atmosphere appear red as will sunsets. Your planet would have to have no atmosphere or an atmosphere so thin as to be invisible and unable to suspend atmospheric dust and suspended water wouldn't be allowed to prevent rainbows.
Liquids in general would have to be eliminated as they are prone to similar colouring effects and they also absorb various wavelengths of light. Suspended particles can shift the colour spectrum as well.
For things to appear in shades of grey to a human there must either be low light so human colour sense doesn't work or everything on the planet's components must be only black and white.
The former is meaningless as humans supply their own light sources. This means the latter must be the case in order for the original proposition to be true.
Since you're talking about a planet with a surface you're referencing a terrestrial planet. The surface of terrestrial planets are made largely of rocks which are themselves made of minerals and fragments of other rocks. Such a planet would have to have to have formed from no almost no transition elements as transition elements often form colourful compounds. You'd have no gold, copper, iron, manganese, chromium, silver, etc, which aside from making many pretty colours are also useful for industrial purposes. Since planets are formed from star-stuff and stars inherently go about making transition elements this is all but impossible. The planet would have to be artificially constructed to avoid these.
Your planet would have to be shielded from asteroids/meteors as many of these are made from transitions elements and over geologic time you can expect substantial numbers of these to impact a planet.
Radiation shielding would be required to prevent radiation from initiating nuclear changes that could result in the formation of transition elements. This would also necessitate the planet being made from only non-radioactive isotopes to prevent them decaying into colour-producing transition elements. Radiation can also effect colour changes, such as causing quartz, clear and colourless, to be converted to smoky quartz, clear and brown.
However, transition elements are not the only things that produce colour. Other elements are also coloured such as sulphur, chlorine, iodine, bromine, fluorine and these often produce coloured compounds. Minerals can also change colour through tenebrescence. And normally colourless elements can also form coloured substances, such as sugar solutions in water.
All the discussion on minerals above involves colour centres, regions in the solid where incoming photons interact with the electron stucture of the material but there are other mechanisms such as rainbow-like inteference patterns seen when stones have an internal fracture. These are actually also visible when fractures occur near the surface of otherwise opaque rocks, including obsidian which is opaque and black. Rainbows have been mentioned but one also needs to prevent dispersion through other clear materials such as occurs in prisms.
Vulcanism isn't allowed simply because molten rock glows red.
The only way around this is to have manufactured the planet from a limited number of materials that are not coloured and which are maintained to prevent the formation of colour.
[Answer]
Well... yes, the planet itself can be entirely gray.
[](https://i.stack.imgur.com/KSoRh.jpg)
...although there were some exceptions to the rule.
[](https://i.stack.imgur.com/PuJwU.jpg)
*Although the color in this image is heavily exaggerated, the astronauts of [Apollo 17](https://en.wikipedia.org/wiki/Apollo_17) were [very excited](https://www.youtube.com/watch?v=kQ-7212_idA) to find orange-colored lunar soil near [Shorty Crater](https://en.wikipedia.org/wiki/Shorty_(crater)), because the Moon is otherwise* ***expected*** *to be entirely grey.*
But can it be made so that **everything else** seems grey as well, no matter what color it "actually" is?
Not unless you invent an atmosphere that [permits only one (narrow band of) wavelength of light to pass through it](https://en.wikipedia.org/wiki/Optical_filter#Bandpass) and that effectively absorbs **everything** else, or invent a LED/laser-star.
[Answer]
Even if you could create an entirely monochrome planet: Things you would bring there, will remain colored. So if you brought a red flashlight with you, objects would appear red. Moreover, you could not entirely protect the planet from extraterrestrial changes: Stars change their color in their life cycle, for example.
Anyway, a planet could be *almost* monochrome. In an ideal situation, you as a human might not even notice the minor side-effects of a planet not being entirely monochrome.
There are also many useful aspects which were mentioned by other users. Hope I could help you :)
[Answer]
White light contains all of the colors(i.e. wavelengths) in the visible spectrum. So when white light shines on an object, that object will appear different colors depending what wavelengths are reflected and absorbed. The only way to make the human eye not distinguish objects based on color is if those objects are illuminated with light from a single wavelength or a very narrow range of wavelengths. At first, humans would view a single wavelenght world as all one color, red for example. Everything would appear various shades of red, but no other color would be visible. This red scale would eventually fade to a grayscale as after about an hour or so for the same reason your eyes compensate the color correction when wearing tinted sunglasses or ski goggles. [More on color detection](http://sciencelearn.org.nz/Contexts/Light-and-Sight/Science-Ideas-and-Concepts/Colours-of-light)
While most objects would appear colorless, other than slightly tinted red, it might still be obvious what color the single wavelength of light illuminating the environment was if one knew the color of objects before going to the new single color environment. While other colors would appear in grayscale of brightness, reds and whites would be indistinguishable if they were equally as reflective since they same amount of red light would reach your eye. For example, red paint on a white wall would be not be visible since the red paint and white wall would both reflect and equal amount of red light. This effect is used in some board games to obscure answers with colored patterns only visible through a card reader.
Illumination with a single wavelength is the only way to create a grayscale world, outside of microbes, as mentioned before, or chemical deficiencies in the people seeing but is subject to breakdown if a light source of a different color is present. Solar illumination with only a narrow range of wavelengths, such as if you planet was around a red dwarf that produces very little light of other colors, would not prevent other light sources from showing the true color of other objects, such as if your explorers brought a flashlight to the planet or they set a fire. Therefore, I think the best solution is an atmosphere that absorbs all wavelengths but one.
The Earth's atmosphere absorbs light from the sun at different wavelengths but allows most of the visible light to pass through. Your planet's atmosphere could have a number of gases that absorb all but a very narrow range of visible light, making the light that reaches your monochromatic. If the atmosphere was thick enough, light produced at the surface would also be absorbed and the explorers would not be able to see any color except the one unabsorbed color. A white flashlight would turn red after some distance, depending on the optical depth of the other wavelengths in white light in the atmosphere.
[](https://i.stack.imgur.com/HcOhY.png)
An almost totally absorbing atmosphere would cause some problems with life since very little energy would reach the surface. Photosynthesis on Earth occurs at nearly all wavelengths in the visible spectrum, so whatever plant life existed on the planet would have only the one wavelength to use. Also, animals on the planet would never develop color perception because it would be useless. The plants could use a different wavelength, just outside of the range that humans can see, potentially solving the energy problem. Also, if the atmosphere didn't block ultraviolet and infrared light that is outside of the human visible spectrum, animals on the planet probably will have developed eyes that can see in those wavelengths. Perhaps the dull monochromatic world to humans is actually a very vibrant, colorful world to those who can see the 'colors' we can't.
And one final other proposal would be to have a similar absorbing atmosphere but with nearly no light reaching the surface and have some sort of bioluminescence illuminating the environment at one wavelength as another way to create a monochromatic world.
] |
[Question]
[
[](https://i.stack.imgur.com/7QrPg.jpg)
Something like the above (Natural Springs by [Ellie Cooper](https://www.artstation.com/artwork/2xwJkK)) - either where the water originates from atop the tree through regular rainfall, or is directed up and into the tree via the spring (or some other source) below - somehow. I'd ideally like these to be created naturally, but man-made alterations are also possible if that would make them work when they otherwise wouldn't. It doesn't need to be a global phenomenon either, it could be local to a certain area of an otherwise Earth-like planet.
[Answer]
No, at least not with classical trees. A tree can be defined as
>
> a woody perennial plant, typically having a single stem or trunk growing to a considerable height and bearing lateral branches at some distance from the ground.
>
>
>
Branches with leaves can't be dense enough to hold water, as this would defeat the purpose of the leaves on the trees. A leaf converts sunlight to usable energy and if it's packed tight enough to hold water, it wouldn't get sun. Furthermore, a leaves are designed to let water drip through to the trees root system below.
If you want something like on the image, I would suggest going with massive fungus which can be "waterproof" and don't undergo photosynthesis.
[Answer]
**Of course there can!**
Unless you're looking for a biologically true answer,1 in which case they can't because, looking around the Earth, there aren't any. BUT! I happen to know ~~Mephistopheles~~ a particular mad scientist2 who thinks that with some suspension-of-disbelief gene splicing and some *particularly unnatural* "stuff," you might achieve your ~~evil plan~~ goals with the following ideas:
1. The tree is massive and grows a natural bowl surrounded by a leaf barrier. The leaf barrier is meant to slow the wind to minimize evaporation of the accumulated water.
* One value of the water may be to foster the growth of bacteria, plant life, or animal life, that leaves behind a nutrient the tree needs in quantities it can't get through the soil. This could be a naturally-forming tree version of [soil inoculant](https://extension.uga.edu/publications/detail.html?number=C990&title=Soil%20Inoculants).
* Another value to the water would be that the tree is a massive water-stealer, in which case everything under the tree is a desert.
2. One method of filling the bowl would be rain... but that's often capricious and, despite what our mad scientist just suggested, sunlight is going to evaporate the water pretty quickly no matter how deep it is. Therefore, I'm voting that the tree is capable of some world class transpiration. Transpiration is the process by which plants move water from the soil to where they need it. Some of it is used during the photosynthesis process - the excess is expired through the leaves (not unlike sweating, but in a much finer process that's a lot more atmospheric than it is fluid). But, your tree is BIG! And that means the process shifts from atmospheric to fluidic. Since plants do this today, yours simply need to do it on a larger scale with greater efficiency.
* What this really means is that your trees can only form along underground rivers or over large aquifers. They need a large source of underground water. Soggy soil isn't enough.
3. Finally, you might want to think through the waterfall concept. Consider the laws of thermodynamics, which basically say that if you've been ~~suckered~~ convinced to buy something that produces more energy than goes into it, somebody's probably stealing your identity along with your money. In other words, a tree large enough to form a waterfall worth looking at would need a MASSIVE water source to justify the amount of waste water dumped on the ground below. Therefore, you might consider *virga.*
Virga is that streak of cloud you see that kinda looks like rain falling to the ground — but nothing actually hits the ground due to evaporation or sublimation. Basically, there isn't enough liquid water to survive the trip. If your trees resulted in virga (which, IMO, would be massively cool, the mad scientist likes it, too), they would be more believable since the massive water source need not be so massive.
*And for the record, my mad scientist friend loves this idea because basically it's the most beautiful and amazing thing on the planet — and nothing and no one can live near them because it's a honking desert underneath them. See footnote #2.*
---
1 *And, frankly, if you really are looking for an answer to your "can this fantasy idea happen in real life?" question then you're kinda in the wrong place... with the exception of our Anatomically Correct series, but that has rules. Remember, this is a place where you, the creator of a fictional world, seeks help to create that world's rules and expression. Thus, if you're asking, "My wife wants one of these in the back yard, how can I get one?" the only answer is "concrete is your friend!" But if you're asking, "how to I get these into my world in a believable manner?" Read on.*
2 *Muahahahahahaha!*
[Answer]
In terms of physical possibility, I think that picture is honestly a bit of a stretch, just because water is so heavy that I doubt any amount of wood would be able to hold that much of it up. But if the trees are a bit smaller, or the planet has a lower gravity, or these trees are made of something much stronger than wood, then sure, why not?
The real question is an ecological one: *why* would something like that exist? Here's my offering:
Suppose there is a region of your world that consists of a very nutrient poor desert. It would be very hard for plants to grow there, except for a lucky geological coincidence: underneath the surface is an [artesian aquifer](https://en.wikipedia.org/wiki/Artesian_aquifer), meaning that if you dig down far enough not only will you find ground water, but it's under pressure, so if you dig a hole the water will come up to the surface, forming an artesian well.
A tree with a deep enough root system can reach the water, but why would it channel the water up into its canopy instead of just growing its roots down into the aquifer?
Well, earlier I mentioned that this desert is very nutrient-poor, and trees need nutrients to grow. One excellent source of nutrients is bird poop. How can a tree attract birds to a desert? By growing a bird bath!
So imagine some kind of migratory flamingo-like bird. They eat plenty of food in the fertile regions of the planet, but then when it's breeding season they fly into the desert to mate and lay their eggs in the tree-tops, where they're safe from predators. The trees provide nesting sites and large, shallow pools of water for them to drink and perform their flamingo-like mating rituals, and while they're there they poop out all the nutrients they've eaten elsewhere, fertilising the trees. It's a reasonably plausible symbiotic relationship.
Of course, the pressure in the aquifer will vary quite a bit, and perhaps after the rains there will be so much water that it spills constantly out of the canopies, and the scene will look not unlike the picture you posted.
Edited to add: from a [video link](https://www.youtube.com/watch?v=DkPOCyCU7Pk) in LazyReader's answer I discovered that this is actually somewhat biologically plausible. Apparently there is a very old tree in Montenegro which has a hollow trunk and sits on an aquifer that, after several days of rain, has enough pressure to force it up through the trunk. Here's a couple of screen grabs:
[](https://i.stack.imgur.com/9E2sC.jpg)
[](https://i.stack.imgur.com/8Fw3g.jpg)
One can just about imagine that under the right conditions, evolution might start to take advantage of this effect.
There is [another video](https://www.youtube.com/watch?v=6RjE0X4-sA0) here with a little more information about this tree.
[Answer]
Perhaps giant fungal organisms? Mushrooms are effectively > 80% water, so with a little stretching of the genealogy one could imagine giant mushroom-like organisms that sponge up large quantities of fluid from nearby (or underground) sources. It could then continuously eject the excess from atop its structure via large pores, or perhaps on cycle (weather / solar cycles) open up its pores and eject mass quantities of fluids. Fungal organisms have been observed to use water to eject / propagate its spore content here on earth...
[Answer]
From a certain point of view, such things already exist, they're waterfalls found on buttes called Tepuis:
>
> A tepui /ˈtɛpwi/, or tepuy (Spanish: [teˈpuj]), is a table-top mountain or mesa found in the Guiana Highlands of South America, especially in Venezuela and western Guyana. The word tepui means "house of the gods" in the native tongue of the Pemon, the indigenous people who inhabit the Gran Sabana.
>
>
> Tepuis tend to be found as isolated entities rather than in connected ranges, which makes them the host of a unique array of endemic plant and animal species. Some of the most outstanding tepuis are Auyantepui, Autana, Neblina, and Mount Roraima. They are typically composed of sheer blocks of Precambrian quartz arenite sandstone that rise abruptly from the jungle, giving rise to spectacular natural scenery. **Auyantepui is the source of Angel Falls, the world's tallest waterfall.** ([source](https://en.wikipedia.org/wiki/Tepui), emphasis mine)
>
>
>
The change for your world is that the water pressure forces the water up through the non-homogeneous trunk of a tree rather than through the non-homogeneous rock of the tepui. And there's an example of this after the image.
[](https://i.stack.imgur.com/su7wk.jpg)
Now for the example of water forced up through the trunk. If you're looking solely at a tree, consider the following two YouTube videos. The first is a tree with a waterfall that occurs only when it rains. The second is more on point where heavy water saturation in the local area appears to push water up through the trunk to create a waterfall... something like what you're looking for.
* [Waterfall via Rainfall on the Tree](https://www.youtube.com/watch?v=1ueS1YqDkbA)
* [Waterfall via water forced up through the trunk](https://www.youtube.com/watch?v=DkPOCyCU7Pk)
[Answer]
**Hyathodes.**
[](https://i.stack.imgur.com/1vqgY.gif)
<https://www.botany.one/2017/07/hooray-for-the-hydathode/>
Hyathodes are pores on leaves of certain plants. When root pressure is great enough, excess water escapes thru the leave pores and dribbles out. This is called guttation. I think it is kind of an escape hatch so the excess water does not damage the plant.
If there were serious root pressure (for example a dry adapted tree during a wet time of year) I could imagine enough water coming up from the roots and out thru the leaves to accumulate.
Better though is a tree that did this on purpose. Consider the aphid. It drinks great quantities of tree sap and poops most of it out. Tree sap is protein poor and the aphid must process a lot of it to the the protein it needs, throwing out the rest. So too these trees. They process great quantities of water, retaining the nitrogen, phosphorus and iron they need and throwing out the rest as a cascade off the leaves.
[Answer]
One humid morning in real life I witnessed a situation where it was raining under the trees. The air was warm and moist and the leaves of the tree were apparently cool. Water was condensing on the leaves and falling to the ground like a gentle shower. Your tree could condense moisture from the air and funnel it to a specific path within the structure of the tree and let it fall to the ground in a stream. This would be dependent upon a constant supply of warm humid air moving past your tree.
[Answer]
Take a look at [Cushion Plants](https://en.wikipedia.org/wiki/Cushion_plant).
[](https://i.stack.imgur.com/Mm7Sq.jpg)
They are very low-growing here on Earth, but they are a true woody plant with leaves, rather than a moss or grass (which they do resemble). Their canopy is extremely tight - not watertight - but they also form mats underneath the growing canopy to conserve their dead leaves as insulation and compost.
You could imagine some sort of large-trunked version with a similar canopy, where the under-layers and branches form a dense, spongy 'aquifer' that can hold water. It would probably mean that the waterfalls would come out of the sides of the canopy, rather than flowing out of a 'bowl', and they wouldn't easily form permanent 'lakes' on top, but it seems at least plausible.
[Answer]
It's possible, you just need Giant trees, why normal trees won't work? Because water won't accumulate in a pond, it will simply fall off the leaves.
But giant trees have a problem with gravity, the taller the tree the harder it is to pull water from the ground up to the leaves, but giant trees have evolved a rain chamber that gaters water from the rain to overcome this obstacle.
[Answer]
The trees grow over geysers which push the water up inside the trunk. The reason for them to grow over a geyser which pushes hot water up their trunks is that there are minerals in the water they need. The minerals in this high concentration can only be found in water from the depths of the earth's interior. These minerals also contribute to the stability of the trunks so that they can withstand the pressure and heat. In the treetop there is a basin in which the water is filtered by e.g. roots. The filtered water flows down in the form of waterfalls on the sides of the treetops.
Because the trees filter the water so well, the thermal pools under the trees are a popular travel destination. Nowhere else can you find cleaner water.
Didn't do the math about weight or anything. I just tried to find a reason why there would be water in the treetops.
[Answer]
Generally speaking, a tree's roots extend as far as its branches extend. If the branches caught and retained water like the image, then the soil around the root system would dry out and the tree wouldn't live very long. I suppose the tree could evolve some way to absorb water through the canopy instead of the roots, but that's a distinct enough change that you it might not be classified as a "tree" any more.
Also, water will reduce the amount of light that reaches the tree's leaves. Water is generally a bit murky, but even crystal-clear water will have some portion of the sunlight reflect off the surface. This reduces the plant's ability to photosynthesize and would be a significant evolutionary disadvantage.
But let's forget about all that for now. Pretend you have a magic tree with roots that extend to an aquifer and that doesn't need sunlight at all. You *still* won't get something like you see in the image, at least not for very long. Take the small tree-pool on the left as an example. Based on the height of the woman standing near it (let's assume she's 1.7m tall), the tree-bowl appears to be ~1.5m deep and ~4.3m across. That's roughly equivalent to a medium-sized [above-ground swimming pool](https://www.homedepot.com/p/Independence-15-ft-Round-52-in-Deep-Hard-Side-Metal-Wall-Above-Ground-Swimming-Pool-Package-PURB1552HD1/313231934). Given the rate that the water is flowing out of that tree, a completely full tree bowl would drain in no more than a couple of hours. The square-cube law says the larger trees could drain for longer, but likely not more than a day or so. You could see a spectacular sight like the image immediately after a large rainstorm, but they would quickly empty and you'd lose the waterfall effect.
The small tree next to the woman subtly reveals the only way you could get a scene that looks remotely like that image. That tree's bowl is slanted at a rather sharp angle, and there's water visible at least halfway up the bowl. This implies that the tree isn't holding or storing any meaningful quantity of water. The water is coming from somewhere else and the tree is simply funneling it into a waterfall shape. Some of the smaller trees in the foreground are dumping water at rates that are low enough that they could conceivably be fed by an underground spring and up through a hollow trunk.
The large trees in the background would almost certainly be an impossibility in the natural world. The amount of energy needed to push water that high combined with the sheer volume of water coming off those trees means that the source water is under an unnatural amount of *consistent* pressure (geysers build up pressure and then spray in a burst, not a continuous flow). Even if that pressure *didn't* blow a big hole in the rock, there's no way a young plant would be able to take root and survive while being blasted by a fire hose.
If you want to replicate this sort of visual experience in your Earth-like world, your more realistic option is for these "trees" to actually be rock/mineral formations. The tree-like appearance is due to the various mosses and plants that grow on top of them. This entire area was originally an underground cavern. Springs ran through the cavern, eroding away the softer rocks and leaving behind stronger ones. The cavern roof eventually collapsed, which is why you can see through to the sky. The large "trees" in the background are pillars of erosion-resistant stone topped by a chunk of what was previously the ground that sat atop the cavern. The smaller "trees" in the foreground are concentrated mineral deposits that accumulate around the openings where the spring's water exits the bedrock. An arrangement like that would get you 75% of the way there. You'd still have to figure out how to push significant volumes of water up to the top of the larger "trees", and I highly suspect you'll need artificial assistance for that. Perhaps your inhabitants liked the visual effect of the smaller structures and wanted to replicate them on a larger scale.
[Answer]
Actually the structure on picture could have a non-tree explanation.
They're mineral deposits from the water, created on contact with air.
Somewhere deep there is a reservoir of water with high mineral compound, like quick setting concrete, that solidifies on contact with air. These are pushed up through the cracks and erupt as geysers. But because of the mineral buildup, you end up with mushroom like structures, as falling water deposits the minerals on edge of the structure.
The result is a very large stone structure like in the picture, with green fungus growth.
[Answer]
# Yes, you have them in real life
Many plants have [drip tips](https://www.edtechlens.com/blog/rainforest-kids-science-plants-control-rainforest) which is a heavy-precipitation adaptation to allow water to flow off of their leaves. This creates small waterfalls. Provided the scale of your setting is small enough (e.g. humanoid characters somewhere between 1mm - 10 cm in height) leaf-based waterfalls will be almost an inevitability.
[Answer]
Giant redwoods have quite interesting canopy ecosystems. See <https://www.savetheredwoods.org/grant/sponge-like-mats-make-good-habitat-in-redwood-canopies-wandering-salamanders-benefit/>
Notably, they are big enough that they can support soil formation. Scaled up you *could* have enough soil to have pools, and when the pools overflow, waterfalls. However, you're unlikely to get these at the edges of a tree like in the picture, simply because the whole top of the tree would need to be a pool, or the pool would need to form at the edge.
Basically, yes you could conjure up an ecosystem of very large, fairly densely packed trees that have behaviour like this.
[Answer]
The Traveller's Palm is known for its ability to trap water in the base of its leaves.
<https://en.wikipedia.org/wiki/Ravenala>
Another plant whose geometry leads to trapping water is Aloe Vera and similar plants.
<https://en.wikipedia.org/wiki/Aloe_vera>
Aloe Vera lives in a dry climate, and I would speculate that it could evolve to catch moisture in its leaves and funnel down to the centre where water could be absorbed. It's going to be tough to get enough water to be of any real advantage to a tree though. I would suggest heavy rainfall only about once a month would be the most conducive to developing a large plant with this characteristic. Of course, when the rains do come any excess will cascade off the leaves.
Aloe vera has a short stem, as do many arid plants, as it doesn't compete for light with its neighbours. There are plants in arid zones with tall stems. For example palms have a taller stem so it might be easier for a palm to evolve into a tree with a water trapping ability than Aloe Vera.
I can't imagine the diameter exceeding 10m though. Some of the trees in the painting look over 100m in diameter, bigger than any natural trees, and that's a separate issue.
] |
[Question]
[
This story takes place about 300 years in the future and humanity has since come into contact with hundreds of alien races, you get the picture. Basically, I have this character who is half human and half alien, but the issue arises in that her alien heritage was an infamous and feared race thought to have gone extinct years ago. This puts a pretty hefty bounty on her since she possesses said race's key traits. I won't get into all the details, but this begs the question of "why go to the trouble of trying to re-capture her if cloning is an option?"
Based on what we currently know about cloning (or theorize), is there some biological/genetic phenomenon that would render her unable to be successfully cloned?
[Answer]
**The DNA is just the DVD, without a DVD player it is useless.**
If the characters mother is the alien then its all fine.
The technology to clone a creature has existed for a few years, but that just means putting their DNA into an embryo that still needs to be carried to term in a woman. An artificial incubator (like in Star Wars) may be in principle possible but they are so complicated that I suspect they will never be invented.
So someone takes this character's DNA. They check it, it has a mix of human and alien. They place this in a human embryo, in a human woman, and it miscarries. It could be that this specific mix of alien/human just cannot be incubated inside a human. (Perhaps an alien Fetus needs some specific nutrients the human body does not produce). Our original character avoided this problem by having an alien mother.
In order to make another person with her powers you would need a alien female to carry the baby, and if these aliens are considered to be extinct and no one can find one then their is no risk that another copy of her could be made.
[Answer]
**It's not that they can't clone her, it's that they're too lazy**
The one thing no cloning method we know of has ever been able to do is produce clones that are the same age as the original donor. When animals have been cloned in the past, they are born as infants and slowly grow to adulthood the same as any other organism. No one has been able to find a way to "speed up" aging in an appropriate way so you have a clone you started growing a few months ago that is the same age as the adult donor. So if you want to clone a half-human, half-alien and have them do things for you that the adult individual can do, you have to wait the necessary time for them to grow to adulthood.
For humans that's really fricking long, about 15 years or so unless they just need their thumbprint or DNA to unlock something. Or the bad guys can just kidnap the already existing adult individual and threaten them into doing their bidding because they're lazy and don't want to wait the 15 years until their clone reaches a physically mature or near-mature state, nor expend the time and effort into raising that clone into developing an emotional bond with them so they will do as they say.
This has the added benefit of making your antagonists look more villanous, as taking inefficient shortcuts that harm other people rather than doing it the drawn-out, but more moral and efficient way has a side effect of enraging audiences (in a good way, as in they hate your villains more).
[Answer]
In most (if not all) earthly life forms, every cell contains all of the genetic information needed to create the entire organism. Perhaps that is not true of the alien race which is half of your character's heritage. Perhaps that race is made of a variety of specialized cells, with the full genetic map present only in reproductive cells stored safely, deep within their bodies.
If this were the case, then cloning an entire parent from a daughter's stray blood or flesh, or from any of her sheddings or biological waste, would not be possible. The full genetic map is not present in any of those parts.
But if you capture her and very perform surgery to get at her shielded insides, then and only then will have what you need to bring back that great warrior race.
[Answer]
[DNA is not the same in every cell of the body.](https://www.sciencedaily.com/releases/2009/07/090715131449.htm) Mutations and small changes exist. In an alien-human morph, it's not unreasonable to assume that the DNA would be all over the place and vary strongly from organ to organ and location to location; simply taking a skin or blood DNA sample wouldn't provide the full spectrum of DNA required to clone a viable creature.
[Answer]
The infamous and feared race was not a naturally evolved species. It was a weapon, created to fight wars for its masters.
To keep that weapon unique and to keep them from being easily duplicated by the master's enemies, they were equipped with trickster DNA.
The Trickster DNA copy-protection technique involves endowing each cell in the creature with hundreds of times more genetic information that is needed for replication, encrypting it so that each cell can only replicate itself consistently when provided with a specific RNA key. In the absence of that key, attempts to trigger replication can lead to all manner of chaos because included in that extra genetic information is the blueprint for every viral contagion know to the galaxy.
Lovemaking is a dangerous activity when a trickster is involved. You either get a kick@ss hybrid as a child, or planetary genocide. In the case of your character, her father got lucky in more than just the conventional sense of the term.
[Answer]
Is it not possible, in your story, to simply make it so that "they" do not actually/yet have a copy your character's DNA? It could be that the bounty is out on her because they would like to strap her down and scan her DNA.
[Answer]
Epigenetics. As cells specialise, they lose their potency, mostly because of epigenetic modifications to the genome. Genes that are not needed are silenced and packed away tightly to allow more efficient use of the genome needed for running that particular cell. There are also epigenetic modifications that are inheritable by offspring. One of the bigger roles of these modifiers is keep things such as transposable elements, strips of DNA that can detach from DNA and attach in another place or create copies of themselves that can attach into new places, locked in place and silent.
Some of the modifications governing the two cases described are different, but some like methylation have putative roles in both. To properly clone something, you need to strip the epigenetic modifications, lest you end up with developmental issues due to genetic material that has already specialised. Current cloning methods rely on finding and using nuclei from more potent cells (stem cells) with less specialisation-related epigenetic modifiers to get around this.
So, the extinct aliens have genome that is filled with transposable elements, which are contained with epigenetic modifiers indistinguishable from epigenetic modifiers accrued during cell specialisation. Strip the epigenetic elements and the transposable elements go wild destroying the whole functional genome of the species.
[Answer]
A similar issue was addressed in the Vorkosigan saga
Miles Vorkosigan suffered teratogenic damage due to a chemical attack on his mother while she was pregnant with him, giving him weak bones and twisted legs.
>
> Later in the series he is cloned in a plot to replace him, but the
> clone came out looking perfect(because the damage to Miles wasn't genetic) and so could not be used in the plot
>
>
>
you could introduce some teratogenic damage to your character that wont be easily reproducible in a clone, perhaps a brain abnormality which is known because an MRI image of her brain from a medical exam has leaked.
Alternatively anything uniquely identifiable that your character has that can't be stolen or replicated, for instance an embedded ID chip that holds a [private key](https://en.wikipedia.org/wiki/Public-key_cryptography)
[Answer]
Make the "hybrid" nature the key to the problem. Make the two races biologically incompatible, so that any hybrid needs to be raised in an artificial womb. In that environment, it was possible to provide two separate nutrient streams for both backgrounds.
Now, the clone would need such an artificial womb, too. That's still possible. The nutrient stream for its human (mammalian) side is no problem either. But how do you create the nutrients for its alien half? There's no documentation, nor a living female alien to study.
Also, there might be some immune system challenges during fetus development which need to be addressed, but which are impossible to work out without an actual alien to study.
[Answer]
# You get a baby
If they cloned your character successfully¹ they would get an undeveloped (half-)alien. Not only physically, but -most importantly- also mentally.
It might be feasible, [as a long-term plan](https://tvtropes.org/pmwiki/pmwiki.php/Main/TheChessmaster), technically. You would need to slowly² raise him, and you might end up with a very loyal servant. But initially you would have a baby you are unable to communicate with, but having those interesting traits it's unable to control. Let's suppose they are powerful telepaths, which could break into the mind of those around you. Surely, the abilities of a baby would be nothing to their parents. However, those nurses you wanted to take care of your clone, would have constant headaches, as the baby would simply throw its thoughts all around it. Oh, and a temper tantrum would end up with many casualties.
On the other hand, your character has learnt to control its thoughts, and will not let them slip outside,³ so it will not inadvertently be dangerous to people around him. You can also communicate with him in your galaxy variant of newspeak. He's unlikely to love their captors, but they could deceive / extort / torture / bribe him so he collaborates with their plans.
¹ It's not that clear, see other answers, but assuming they managed to do that.
² Did I mention how many centuries do they take to fully develop their potential?
³ Basically, it's an automatic thing for him
[Answer]
Was she a natural hybrid? If not, you could check out the various ways that [rat/mouse hybrids](http://www.ratbehavior.org/RatMouseHybrid.htm) have been attempted for ideas. In particular, if the hybrid character is a chimera, cloning won't work unless they can reproduce the particular mix of both species' cell lines. In the case of a secondary chimera, you'd need to know exactly what tissues were xenografted and at what stage of development, or else your reproduction won't be the same and might not have the abilities you're hoping for - or even be viable! Furthermore, especially with a secondary chimera, you could have serious trouble getting a hold of one cell line if it's not represented in blood, mucous membranes or hair follicles. And understanding that she *is* xenografted and which cell lines are xenografted would be considerably harder if the villains don't have access to her to run tests on.
Furthermore, note how many of the methods that produce viable laboratory-created hybrids do so only as a small proportion of the total attempts? If only 5% of hybrids are actually viable, they could easily lack the resources to keep trying long enough to get a success, or if they don't luck out early enough, they could mistakenly assume that they've got the method wrong.
[Answer]
The extinct race was feared because they were bio-engineered weapons. To prevent the proliferation of this weapon the species designers created the species as an RNA based organism vs a DNA based organism. This means that every cell division in a creature cloned from the extinct race has a very high chance of mutation and clones quickly succumb to cancer if they even reach maturity.
In fully developed specimens of the species they have a emergent body system that prevents the mutation of the cells RNA when dividing allowing it to function like a normal DNA based organism. Normal procreation of the species allows the mothers RNA replication protective system (RRPS) to prevent a fetus from mutating while in the womb until it is mature enough that its own RRPS takes over.
[Answer]
Yes, Roger Penrose hypothesizes that humans contain quantum processes.
In fact, (in your story) it turns out that Penrose was on the right track.
But humans are not quite that evolved yet.
Humans don't contain quantum processes.
# But that race of aliens DO include quantum Penrose processes in their brains...
Bingo.
Our half-breed heroine also includes quantum Penrose processes in her brain.
You ***can't clone a quantum object***...
she is utterly, utterly unique and ***unclonable*** in a world where cloning is commonplace.
Great plot.
[Answer]
**The DNA doesn't match the body**
The hybrid in question wasn't grown from DNA but actually 3d bio printed using the DNA.
In the Fifth Element, Leeloo has her whole body reprinted from a sample of her DNA
[](https://i.stack.imgur.com/3ZW0L.png)
Now there is no reason a body couldn't be printed in a different form using the same DNA. Now if someone took said DNA and grew it out, it wouldn't give the same form and being a hybrid of two alien species, may not even be viable to survive.
[Answer]
If you are talking alien, why assume they are DNA, or even carbon-based for that matter? When you say hybrid, people assume mixing humanoids through reproduction. But what if you have something like a silicon-based bacterium that creates a hive-mind from a sufficiently large aggregation of independent cells. Perhaps, this bacterium was a sentient being once, or engineered by other sentient species for some purpose (memory, war, as a tool, etc).
Now a hybrid would be something completely different: it would be a mass of these creatures living in a human host in a symbiotic relationship, giving the resulting being the sum of their powers. Part of the plot could be that this has been tried many times in the past by many species, but always resulted in spectacular death, or the bacterium taking over the whole planet or whatever. Perhaps one such experiment could be the reason the bacterium was supposedly wiped out to begin with.
This would present the motive for capture, and the inability to clone. There is simply nothing to clone. The human portion is just human, but the alien is the last remaining culture of what was once a non-carbon-based hive mind bacterial culture. No one knows how to replicate it, and if they did, creating the hybrid is something that no one has ever been able to do.
[Answer]
Her DNA contains a virus.
Her DNA could encode a computer virus that when the cloning machine reads it, is infected and breaks down. Or her DNA contains a real virus that is only activated by the cloning method (by some chemical reaction or physical process used only during the cloning process) which proceeds to destroy all the genetic material in the cloning machine.
It's been (partly) done already <https://www.wired.com/story/malware-dna-hack/> where researchers embedded a hack into a strand a of DNA, so when the DNA was read it caused a buffer overflow in the DNA sequencing machine.
[Answer]
Her cells or DNA exist in quantum states, which makes it un-clonable.
>
> In physics, the no-cloning theorem states that it is impossible to
> create an identical copy of an arbitrary unknown quantum state.
>
>
>
Source: <https://en.wikipedia.org/wiki/No-cloning_theorem>
[Answer]
The telomeres in her cell's nuclei are compromised due to the cross-breeding, and therefore it is extremely hard to create a clone that will survive to adulthood. The telomeres are still there, and are still functional, however it is very hard to bring the cells back to their unspecified state (in order to clone them). She can still live a normal life span.
[Answer]
Something that will make her different, could be something like triple helix DNA, or more chromosomes, and the cloning machine only works on regular DNA
[Answer]
**Gene expression**
[Gene expression](https://en.wikipedia.org/wiki/Gene_expression) does not replicate the entire DNA. There are a lot of chunks of DNA that are inactive, they are not transcripted by the RNA and they do not contribute to the formation of the cells.
Gene expression is often influenced by environmental factors. For example the genes that drive the transition to adulthood during puberty are activated at a certain age, but different environmental or psychological conditions can anticipate or postpone their activation by few years. There is also the case of several chunks of the DNA that are never expressed because they are relics of the evolution and they are present in [almost every species](https://ed.ted.com/lessons/building-a-dinosaur-from-a-chicken-jack-horner).
In your case the explanation can be that even if they have the DNA they don't know the environmental conditions that triggered the expression of the right genes. **Nurture matters**. To replicate the alien traits they not only must get the DNA from your character, but they must also find out how she grew up, what environment she was in when she was a toddler.
[Answer]
one: Androids can't be cloned.
two: Scientists are already well on the way to growing laboratory outer ears that can be transplanted onto people who lack, or have lost, their outer ears. The trick is to create a scaffold for the relevant cells, seed it with collagen, and seeding the resulting collagen scaffold with cells. <https://www.popsci.com/science/article/2013-07/artificial-human-ear-good-shape/>
In three hundred years' time, might it not be possible to fabricate an entire person in this manner? If the resulting manufactured person were seeded with cells from a number of different people, cloning the manufactured person would not be practical. Also, since the collagen scaffold was not a product of DNA replication, cloning a manufactured organism would be doubly impractical.
] |
[Question]
[
A global epidemic of H1Z2 virus has rendered 95% of the population into zombies. The zombies have lost most of their [frontal](https://en.wikipedia.org/wiki/Frontal_lobe#Function) and [temporal](https://en.wikipedia.org/wiki/Temporal_lobe#Function) lobes so the following capabilities are either severely degraded or missing: decisions about right/wrong, suppression of socially inappropriate behaviors, new memory formation and sensory analysis. Viral damage to their cerebellum has rendered them clumsy. Zombies still have beating hearts but healing from injuries is highly impaired.
The zombie's physical capabilities are exactly the same as a humans. They are as strong as, and as breakable as uninfected humans. When they aren't feasting on humans, they are wandering around scavenging on whatever carrion they can find.
Up till now, major apex predators such as wolves, lions, tigers, and bears (oh my) have studiously avoided contact with humans because such contact equaled pain or death. But that is no longer so. Many apex predators now find human-like things wandering through their territories and appear to be easy meals.
There is no doubt that a non-human apex predator is a superior killer to a brain-damaged zombie. Which apex predator would be most effective at killing the most zombies in the shortest amount of time? The zombie outbreak is world-wide so any predator can be nominated.
Assume that H1Z2 is only lethal to humans and has no effect on animals. For simplicity sake, let's assume that H1Z2 does not mutate to have an effect on animals.
[Answer]
With impaired healing, it's simple - bacteria. Historically, more people died from infections and diseases than were ever killed by any other means. Zombies aren't getting antibiotics, so we're back to that old-time death rate. Add impaired healing into the mix with all those open wounds, and sepsis is virtually guaranteed. Come back "28 Days Later" and you can basically guarantee all your zombies will be dead from blood poisoning.
And that's assuming their impaired healing hasn't already killed them from loss of blood. Haemophilia is basically impaired healing, and haemophiliacs have to be pretty careful about cuts and bruises, as well as taking clotting factor drugs. We can safely assume zombies aren't careful and aren't getting their clotting factor shots.
[Answer]
### Dogs plus other Canids
superluminary makes a good point: there would be *a lot* of dogs. According to a [*Psychology Today* article](https://www.psychologytoday.com/blog/canine-corner/201209/how-many-dogs-are-there-in-the-world), there were just over half-a-billion dogs across the planet in 2012. Many (most?) would become feral, though I'm assuming some would be eaten by larger canines, and others would be eaten by humans (and zombies? hmmmm...).
But dogs are only part of the Canidae family. Other members include wolves, foxes, dingoes, jackals, etc. ([Wikipedia link](https://en.wikipedia.org/wiki/Canidae)) who would display equal or greater ferocity then feral dogs. This would mean a likely population of close to 1 billion hungry Canids roaming the earth. Add to that their propensity to hunt in large packs as large as forty anmals (see the same Wikipedia link) -- few other apex predators would be able to stand against the sheer number of Canids. Imagine multiple packs of 30-40 of superliminal's "Rottweiler / Alsatian crossbreed(s)" ravaging through a city, killing off the zombies, rats, and almost anything else that gets in their way.
Now the twist on Bookeater's question: how do you deal with the feral Canid problem?
[Answer]
The animal best suited and able to gnaw the zombie herd down to size would be the rat. They:
1. Exist all over the world,
2. Breed fast,
3. Have a real fast metabolism,
4. Already look at humans to provide the next meal.
I predict they will outdo feral dogs by a good margin. Next problem will be to rid the world of the rat plague...
[Answer]
## Dogs
Post H1Z2 there will be many pet dogs wandering around without owners. Hungry and alone, these will quickly organise into packs, hunting other animals and ultimately attacking their former masters.
Dogs can learn by watching one another. As soon as one dog sees another enjoying a risk-free human meal, it's a slippery slope.
A female dog can have 1 litter a year. A litter is usually between 5 - 8 puppies. With plentiful walking food and no predators, the dog population should expand rapidly until a balance is restored.
The weaker dogs will be selected against. The strongest will survive and breed. I would anticipate some sort of Rottweiler / Alsatian crossbreed coming to dominance within a few generations.
Imagine an uber-scary wolf-like animal, evolved specifically to take down human prey.
[Answer]
I could imagine vultures and other carrion birds being a good solution.
They'd start out by pecking on expired staggerers and then as their numbers increase and they learn not to fear their new prey and would start attacking the most lame ones in a group.
It may even lead to changes in behaviour of those carrion birds over time.
Birds are more numerous than mammalian hunters and should reproduce faster too (I am speculating here).
[Answer]
[](https://i.stack.imgur.com/wBaKf.jpg)
[](https://i.stack.imgur.com/199UN.jpg)
**Hyenas.**
Hyenas make a living off carrion and pack hunting.
The hyena jaw and neck is an impressive feat of biology. For an animal where adult males weigh in at just 120lbs, their 1100PSI bite is *monstrously* powerful and practically tailor-made for crushing bones and general dismemberment. Compare adult male tigers and gorrillas, packing comparable bite force yet weighing in at anywhere from 400 to 800lbs. Wolves bite at only 400PSI and have nothing like the neck and shoulder musculature that hyenas use to tear apart their prey.
Hyenas move in *clans* of up to 80 individuals, and have a height advantage over other canids, being 75-85cm at the shoulder, thus able to tear out humanoid throats with minimal charging room.
Lower body weight than larger animals with comparable force delivery means more massive packs of hyenas more quickly (gestation time is 100 days for every 2-4 cub litter), leading to geometric reduction of zombies as their biomass is converted to hyena biomass. See ["attacks on humans"](https://en.wikipedia.org/wiki/Hyena#Attacks_on_humans).
*Soon your zombie problem will be a hyena problem*.
[Answer]
Diseases. I know it's disappointing, no "bear army vs zombies", but if the zombies are basically wandering humans, with no survival instinct and trying to bite at anything with a pulse passing by, they'll get wounds, eat things not recommended, and do nothing to clean/protect themselves.
So any wound will get infectious, rot, fester, and so on. This will attract all the carrion insects and birds. And any "common" disease, such as flu, gastroenteritis or pneumonia, can become deadly to them (unless zombies still keep enough instinct to drink regularly).
Note: a group of highly contagious zombies can be quite dangerous to the survivors too, even if they manage to kill all of them.
[Answer]
What throws my initial thoughts off is that these 'zombies' are not undead.
They are clumbsy people with severe intellectual impairments - I don't know that they would last long enough for any predator to develop the habits of attacking them.
Most animals avoid humans - it would take a very long time to change that instinct. The big cats and crocodiles might be the large predators with the most impact on the infected, but their numbers are tiny, so would only have the most incidental effect.
The primary cause of death, which will very rapidly kill off most of the zombies, is starvation. Feeding the human population takes a very large coordinated effort - a bunch of zombies stumbling around scavenging for food will very quickly starve to death. This would provide some carrion in the form of the dead humans to feed those still alive, which might then turn into the zombies just skipping the 'wait until dead' part and hunting each other for cannibalism.
Following that, disease is going to take out a lot of them. Humans are not carrion-eaters, so without cooking, I suspect tainted food and water would kill many more zombies than any predation (especially with cannibalism of infected humans).
Injury and infections will quickly kill off most of the rest. Clumsy unintelligent humans with impaired ability to heal, scavenging raw food, will quickly fall victim to even simple injuries turning fatal (either through lack of basic first aid tending wounds or from infections setting in with even small cuts not cleaned becoming fatal).
I would expect this zombie event to largely burn itself out within 2 months at most. Far too short a time-span for predators to even take much notice, much less change their instincts from avoiding humans to preying on them in any significant numbers.
[Answer]
Maggots. Not exactly an apex predator. But whether anyone wants it or not it's natures way of dealing with rotting meat. No number of tooth and claw predators will be able to keep up with the speed they chomp through flesh and reduce the herds to piles of bones and mush.
[Answer]
As you point out, any large predator should be plenty able to kill a human, given a reason to do it. Hunting for food could certainly be one such reason.
[Tigers](https://en.wikipedia.org/wiki/Tiger#Man-eating_tigers) already kill humans directly, and according to Wikipedia ([cited](https://en.wikipedia.org/wiki/Tiger#cite_note-Walker-57)),
>
> tigers cause more human deaths through direct attack than any other wild mammal.
>
>
>
It takes no great stretch of imagination to see those tigers gaining an advantage in a world where killing of these zombie-humans is essentially free of risk yet still provides a decent meal for the animal.
Tigers are not particularly numerous currently, [numbering some 5,000 in the wild](https://en.wikipedia.org/wiki/Tiger#Conservation_efforts), about half of which live in India and a tenth respectively in Bangladesh, Indonesia, Malaysia and Russia. It is certainly possible that virtually absent predation from humans, and presented with a low-risk source of food, this number could rise, but that would take some time; at the very least, you'd be looking at years or decades for any significant increase in the population.
If you want something to present persistent predation on these zombie-humans over time, tigers may be it, or at least a part of the overall answer. If you want a cataclysmic-type predator in our current world, there just aren't enough tigers to go around to provide it, and you'd have to look at predators that are far more numerous in the wild.
[Answer]
One thought I had was that since animals only kill for survival, not for sport, and since the zombies aren't an obvious, direct threat to any animal, it would come down to whatever predator had the greatest caloric needs. But then I remembered having read that **POLAR BEARS** are an exception to this, that they actively hunt humans and will even enter villages to attack. Therefore, they would be the only animal not limited by their actual consumptionary needs.
Now, we just need to figure out how to herd all the zombies into Alaska, northern Canada, Greenland, and Norway.
[Answer]
Noninfected Humans.
Now, most of the zombie problem will take care of itself as mentioned above, but if you're talking apex predators, it will be humans, mainly because of the characteristics of these zombies. You've set up a scenario where someone hunting (or defending) against zombies has a serious advantage over your typical undead zombie: blow the arm off a Romero zombie, they keep coming and will stay around until you deal with the brain, even if most of the body is missing. Cut the arm off one of these living zombies, or otherwise seriously wound them, and they're unconscious due to shock within minutes and dead shortly thereafter.
It's an ideal situation for firepower. Even wounding works because they'll eventually be dead of infection. And given the mental impairment, they can't learn from their own mistakes or observation of others making mistakes, so the same tactics can be used against them again and again.
[Answer]
Diseases affect species in different ways. A disease that jumps species will probably be more of a messy hazard than a symbiote, and more accomodating with established hosts.
So the *same* disease (or a different assortment of strains, implied by your flu notation) might make a different species a better predator.
In fact, infecting the prey for easier killing later might be a specific adaptation (think Komodo Dragons).
So the zombie primates will be preyed on by zombie-infected avians, which have substantial brainpower but have the brain arrqnged in a totally different way. The zombie infection makes birds *smarter* and able to form small-range hive minds.
Crows (smart, gregarious, carnivorous) will be in prime position to pick off zombies. Pigeons will not be interested unless it also gives them a taste for meat. Hawks and eagles and falcons are not forming groups so don't get the hive-mind, but are pretty smart onntheir own. Perhaps the corvids will find a way to work *with* them.
[Answer]
Given the large amount of 95% of the worlds population spread all over the world.
And also respecting that the Zombies are equal to humans except the fact that they behave different (but still taste the same as humans).
Your Zombie Joe would be the biggest threat predator to your Zombie Jim, as true humans will be rare to find.
But your Zombies are everywhere!
[Answer]
Deadly animals are not always predators.
Especially in Africa, some animals (hippo, rhino, somewhat elephant) tend to charge any potential threat. It is their way to teach lions or humans "Don't even think of approaching us".
But zombies are slow learner. They would be trampled by the million.
[Answer]
The Sun + A door + themselves will deal with any zombie horde within a few days at most. I don't see the need for, or time to get, something to be trained up to go kill them.
If they are dead, they will rot within a day.
If they are alive they will die in less than a week due to not getting any water, cuz they won't drink it probably.
If this isn't the case, there is no reason to attack me vs other zombie who are slower, dumber, and in greater number.
The bigger problem is cleaning up, not the zombies themselves.
If you just don't want to follow this, cats and dogs will eat humans and there is enough of them to take care of a zombie horde too. And they would turn on a human if they try to eat them so... yeah.
[Answer]
It would appear as if your virus simply turns people into dumb clumsy psychopaths. This being the case, the zombies are now essentially downgraded monkeys, but as living things, are still insanely adaptable and would probably eventually over come the virus, except... monkeys. Yes, they're not predators, but apart from the 5% of humans still alive, the y are now the Earth's dominant species. If zombies even happen to come their way, they'll seem like hairless monkeys invading their territory, and the monkeys will attack. If not, it's highly possible that monkeys will eventually reach human levels of intelligence, and either, A. The zombies will have come to be smart as well, and war will ensue, or B. Monkeys will take over, and finding human artifacts showing our pasa cruelty to animals, decide we should be purged.
[Answer]
If we interpret the question to apply to efficiency in terms of those zombies that actually enter the apex predator's habitat, then...
**SHARKS**
Definitely one of the most efficient killers out there, especially once they frenzy.
Now we just have to figure out how to herd all the zombies into the ocean...
] |
[Question]
[
A common trope with immortality is that the immortal character hides their true nature by faking their death every so often and pretend to be one of their descendants. They end up adding a "III" or "IV" to their name and claim to have a "strong family resemblance".
It works well for *male* characters but what I found while writing a *female* immortal character is that it would be a lot harder to do given that in Western cultures family name is typically patrilineal rather than matrilineal. Therefore, having the same woman with the same name pop up throughout history would be extremely suspicious.
**My question is how can my female immortal hide her immortality?**
* They are sterile due to the nature of their immortality so having their extended family hide them and pass them off as a distant cousin isn't an option.
* They aren't interested in getting married and losing their family name. In story this is because they were married once and never got over the loss. Out of story it's so the reader doesn't get confused by the character constantly swapping names depending on the time period. Therefore, the "black widow" thing where the female immortal marries a mortal and simply outlives her husband isn't an option. Plus it would raise a lot of red flags that whatever mortal she married has a wife that never ages and can't produce children or heirs (which was often a juicy piece of local gossip in older times). Male immortals often claim in fiction that they have a fake family that no one knew about, which they could get away with due to a lot of cultures having "stay in the kitchen" attitudes where people didn't see someone's spouse, whereas female immortals have fewer options to have a fake family unit that no one knew about to justify a new cover.
* If the immortal tried to pass herself off as a member of an already existing family, there would be a lack of a paper trail compared to a male immortal who can more easily fabricate identifying documents from his prior incarnation. Because again, until recently most societies were very patriarchal and the societally conditioned view was that men were the ones who handled public business and bureaucracy, aside from widows and secretaries. E.g., a male immortal can easily do things like write a will saying "I leave all my stuff to my son John Notanimmortal II, who is totally not me", whereas a female would have more difficulty.
[Answer]
**She is a bride of Christ.**
[](https://i.stack.imgur.com/6XVv5.jpg)
<https://www.history.com/news/women-education-medieval-nuns-church>
Your immortal is a nun. It is no surprise she has no children. It is no surprise that she dresses in an archaic style. It is no surprise she does not have male family members meddling in her affairs. It is no surprise that she can read and write and is frighteningly smart. It is no surprise that she keeps a low profile in the world.
Maybe she periodically moves from convent to convent to disguise her great age. Or better - the members of her convent know exactly what she is. And they like it.
[Answer]
I think that you should consider several points:
1. [A wide use of surnames](https://en.wikipedia.org/wiki/Surname) is a relatively new phenomenon in Western cultures, especially among commoners (the practice was widespread among Romans, though, but was abandoned). Their use also differed from today. For example, in England, most surnames were occupational or locational and did not indicate inheritance prior to the 15th century. It was not uncommon at all to have several people with exactly the same name (John Smith, Richard Carpenter, etc.).
2. [Some surnames are much more common than others](https://mymodernmet.com/most-common-surnames-map/). For example, in Anglophone countries, the most common surname is Smith (and it can be traced far back). The same applies to names (see, for example, [given name statistics for the USA in 1850-1940](https://blog.myheritage.com/2020/04/most-popular-womens-names-in-the-u-s-census/)). Therefore, it is not really a problem to have several women with exactly the same name and surname regardless of their origin, family relationships, and marital status.
3. [Not all Western cultures](https://en.wikipedia.org/wiki/Maiden_and_married_names) and not at all times require (or required) a name change for married women. Anglophone cultures, indeed, had [coverture laws](https://en.wikipedia.org/wiki/Coverture) that among other things encouraged the practice of addressing women by their husbands' names. But I do not recall any Western country that would *require* a legal name change.
*Update following the discussion on comments*: [In 1896-1976 German law](https://chicagounbound.uchicago.edu/cgi/viewcontent.cgi?article=4144&context=uclrev) (West Germany after 1945) required women to adopt their husband's surname as a marital or family name (Ehename). A woman was allowed to add her maiden name to her husband's surname if she desired so. I am not familiar with specifics of the German law and not clear on the usage of Ehename vs Nachname. But it seems that this law can be viewed as a legally required name change. I would greatly appreciate it if someone versed in German law could clarify this point.
Therefore, it is possible to get married and keep the maiden name in most Western European countries. Other people in formal situations may address this immortal character using a married name, but she can keep her original name and her friends can keep using it.
4. If your immortal was born a long time ago, name changes might be necessary to avoid unwanted attention. Names and naming conventions are not static. They change over time. Some names that are now considered to be male were once used for women (for example, [in the mid-1500s Richard was a popular name for both girls and boys](https://www.historyextra.com/period/norman/baby-names-popular-royal-history/)). Of course, you may conveniently name your character in a way that is more or less acceptable using today's standards. However, if your character was born 5000 years ago this name might've not existed at all. So, do your research.
To summarise, **it would not be suspicious at all if the same woman appears throughout history with the same name and surname, given that her name and surname are common enough.** She also can get married and keep her maiden name.
'Paper trail' becomes an issue only if this woman is a member of the nobility or in modern times when identity papers became common and in many places required. As technology advances, the difficulty of establishing new identities will only increase. Moreover, it might make more sense to change names rather than keep the same one.
---
*A side note:*
The name problem is rather trivial. If I were a female immortal I would be much more concerned with problems associated with my wealth. The abovementioned coverture laws did not allow women to own any property or make contracts in their names. 'Black widow' scenario is actually a very attractive option for a female immortal who does not wish to beg for food.
[Answer]
Claim to be a niece. Her brother agreed to send her. With some trickery, she can have the niece stay for a time looking after her frail old aunt.
Just say you are your brother's child. In fact, this is easier than claiming a daughter, because her growing up away from you is expected, though some "visits to my brother's family" would be wise.
[Answer]
### Don't put down roots
You're assuming the immortal is a major society figure who would be widely known. There is no reason why this would be the case. If the immortal has the sense to avoid settling in one place for any length of time, they can easily stay under the radar.
Romanis have been wandering Europe for a very long time. Most of them left very little lasting impression on the communities they went through. They quite likely would all know, but they wouldn't tell a gadjo. Even if it slipped out, it would just be written off as a tall tale from a gypsy trying to con a gullible mark.
Similarly, until the 1800s it was normal for there to be travelling traders bringing luxury goods around villages. If the immortal simply avoids going back anywhere she's visited for a century, anyone who could have remembered them would be dead.
[Answer]
## A Few thoughts:
There are various ways to go about this, depending on the finances of the woman, ethics, etc. (let's call her Mary Shelly). The lack of records is trivial through most of history, and records can be faked or are incomplete.
* **She claims to be a widow:** If Mary Shelly shows up in town, claiming to be the widowed granddaughter of someone who died without descendants around, and she buys the "family" home, who will question it? The woman has a different last name, which OBVIOUSLY is a married name, right? Hey, what do you know, the old guy DID have a granddaughter named Mary, but the real granddaughter died in childbirth ten years ago in a different region, or died at birth, then the records were forged.
* **She's good at faking documents:** Given time and experience and planning, she creates a shell game of falsified documents showing she was from lots of places. Every time a child dies, or a family moves, records of an extra child named Mary show up. Who cares? And who is looking for a forged identity that was forged twenty years ago? For a female, a matching last name is irrelevant - a forged marriage certificate of Mary Schmitt marrying John Shelly (who died in the war) gives her a perfectly valid identity.
* **She has a family of accomplices:** Mary has informally adopted a family (or raised orphans hand-selected to resemble her), who either share or take on the Shelly name. They may even believe they ARE related to her, and cover out of loyalty. They may have real members of the family that share Mary Shelly's name. She owns all the lands and homes, and they move to another town every 20-30 years when she tells them to. The family/orphans get the benefit of wealth, and all they need to do is move to a new town when told and leave records and reports of a spinster/widowed Aunt/niece/sister who manages their affairs when they are away. Given a couple generations, who will remember her? And if they do, any resemblance must be a familial relationship. Members of the extended family might not even need to be in on the secret, so a distant "niece" of hers in town married to a local boy doesn't remember Aunt Mary, but is told by the family not to ask questions about where the family wealth is from. An extra 500 pounds of dowry and everyone loves Aunt Mary.
[Answer]
James Blish wrote a story "Beep", Galaxy, Feb. 1954, and expanded it into a novel *The Quincunx of Time*, 1973, which I happened to mentioned somewhere else today. And by another coincidence I also happened to get a book which includes "Beep" out of box yesterday.
One scene includes the line:
>
> If a women is going to go in for disguises, there are always two she can assume outside her own sex: a young boy and a very old man.
>
>
>
So if that is accurate, perhaps your immortal woman will sometimes impersonate young boys and old men.
If she lives in the same place for centuries, and tries to build up a fortune over the centuries, she might extablish a "family" consisting of several women of various ages who strongly resemble each other, and several young boys and old men, also with a strong family resemblence. And because they are so reclusive, only one at a time will be seen by their few neighbors. And occasionally it might be announced that a older family member died or that a baby was born, though that "baby" won't be seen until years later when it is much bigger.
I also note that in some societies eunuchs were common, so possibly she could impersonate an eunuch at times, explaining why she makes such a feminine-looking "man".
I believe that there been a few other questions about immortals hiding.
Here is a link to one of them that might have more ideas you can use:
[https://worldbuilding.stackexchange.com/questions/158845/how-would-a-young-girl-boy-about-14-who-never-gets-old-survive-in-the-16th-cen/158861#158861[1]](https://worldbuilding.stackexchange.com/questions/158845/how-would-a-young-girl-boy-about-14-who-never-gets-old-survive-in-the-16th-cen/158861#158861%5B1%5D)
Obviously a writer of a story where person A discovers that person B is immortal will want person B to keep their immortality a more or less closely guarded secret. In different stories the immortal might be more or less relaxed or paranoid about their secret being discovered.
And obviously a story set in the present or past can't have someone who is known to medical science to have lived for centuries. Unless it is in an alternate universe, of course.
But if someone wants to write a science fiction of fantasy story - set in a different society than ours - where the protagonist is immortal, they might want to consider whether an immortal might want to keep their immortality more or less a secret or make it more or less public.
There have been many people who claimed to be far older than the oldest medically accepted human, and as far as I know few of them suffered from being considered by many to be extremely old.
[Answer]
## Routinely adopt a daughter from an orphanage
You have what you're considering a problem: you'd have a hard time showing lineage as a descendant. But instead of considering it a problem to solve, you can *lean into it*, making it useful both as a way to pretend to be someone with their Name + Roman Numeral Number format, and give potential investigators a reason to believe it's just a legacy name. As a bonus, said investigators would then be tracing down among incorrect leads following unrelated family lines.
In a village, go to the orphanage, and adopt a daughter. Raise them, and be sure to get lots of family portraits/paintings/pictures over their growing up period.
Once they hit the age of majority, reveal to them that they were adopted, and let them go and try and find out who their past family was - if you know what their name was before that, tell them that and let them change their name legally when they leave.
This has a few advantages - you'd get to know their personality, how they think, and dress, and you get to adapt it before you try to take on their identity. You'd also have 18 years to learn their mannerisms to be able to adopt them yourself, and change with the culture so that you don't seem too old-fashioned at any given time.
Ideally, you'd want them to take the name change either just before you fake your death and take their identity, but you'd want to have a historical record of being that orphan when you remake your identity.
You may need to move around to keep the charade up a few times from some older people who might find it weird that you don't quite sound like your adopted daughter, but you can surely return at a later point to the same house, effectively inheriting your old home, and repeat the process.
This gives you not just a lineage that could be traced, and an explanation as to why you look the same as your mother/grandmother/ancestors (That is, that they were your single parent who raised you), while also leaving anyone trying to chase down your lineage into a dead-end as they track down orphanages and find that "Jane Smith IV" has no genetic relation to "Jane Smith III", but that their commonalities are that they were all adopted and had other parents who had sent them to an orphanage.
Hopefully you don't need to have a backup plan in case your adopted daughter ends up dying before you can take on their identity and have them change theirs to the one they had before being adopted or sent to an orphanage, but in that worst case, you can try again with a newly adopted daughter, and increase the numbering system a bit more.
[Answer]
## She is Korean, surname: Kim
Almost [22% of South Koreans have Kim](https://en.wikipedia.org/wiki/Kim_(Korean_surname)) as their surname. Unrelated Kims marry Kims all the time, and there's no shortage of multiple generations of repeated female names. Nobody would bat an eye.
It's not immediately apparent, but you're likely going to have a bigger problem with their *given* names than their surnames because women's popular given names actually change faster than men's. Consider this: how many little girls do you know named Gertrude, Esther, Mildred, or even Louise or Ruth? Not many I'd bet. And yet all of these were once very common (as attested in my family tree).
In the west, the typical author's solution to this is to use biblical names which are "always" acceptable (likely to change from now into the future though). However even there, Esther and Ruth seem like pretty dated names these days. "Mary" still works though, and for a western female is probably the best bet for an immortal name that won't raise eyebrows anywhere or anywhen (or it's national equivalent).
[Answer]
If your story takes place in a pre-modern society, this is surprisingly easy. In most societies age was not accurately recorded, often someone older than 40 would be said to be 100 and people wouldn't question it.
Those who are close to your character eventually die off due to old age, and people just think of the character as "old". If they do manage to have a friend for 40 years, perhaps they may question why the character doesn't appear to be getting older, but it's likely they'll just accept it. There's speculation this is what happened with Jeanne Calment, those who knew her simply died off or forgot or weren't taken seriously.
So long as the character doesn't have a strong public presence over a hundred years, people simply won't notice the anomaly because you need to have records spanning a great deal of time.
[Answer]
The more thoroughly documented a society becomes, the harder this will be, but one way that this problem could be handled has been used in fiction previously: your (forged) identity documents show you as coming from somewhere where it just so happens that it can't be verified (e.g., a city destroyed in a war, an isolated rural area where "the old Smith place? That burned to the ground back in...", etc.). Once you have a couple of basic identity documents (e.g., a replacement birth certificate), you can "rebuild" your identity a few pieces at a time, somewhere far from where you supposedly came from.
*Friday*, by Robert A. Heinlein, uses this; the title character, who happens to be a lab-grown 'artificial person' (not an android) has papers showing that she came from a destroyed city (Seattle, I think), and during the course of the story, either Mexico City or Acapulco is destroyed in a dispute between the government and a multinational corporation - and in discussing artificial people, Friday says something to the effect that 'a lot of people like me will be "coming from" ...' whichever city it was.
[Answer]
# Gender fluidity
Spend part lf your time as a female, then part of your time as a male, in that order.
Then the male identity "dies" and the immortal disappears. Some time later a woman shows up that looks a lot like that male identity and carries the same full name and looks as the previous female identity.
] |
[Question]
[
I am trying to create a planet that either has no oxygen in the air, or it has very little; i.e. not enough to sustain humans without the use of a breathing apparatus. Large portions of the planet (approximately 50-60% of the surface, compared to Earth's ~70%) are covered with oceans, seas, lakes, and other bodies of water, much like those that are found on Earth. The planet has no native life forms, but in all other respects, assume that the planet is like Earth.
Is this scenario scientifically feasible? Or will the presence of large volumes of water inevitably result in some of the oxygen making its way into the atmosphere?
[Answer]
Possibly.
There are two mechanisms for producing oxygen on Earth (and other similar planets)
1. [Photosynthesis](https://en.wikipedia.org/wiki/Photosynthesis). Water is split and combined with CO2 to make (roughly) CnH2nOn and O2n. Some reduced carbon ends up buried to give a net contribution of O2 to the atmosphere. Note that the combination of photosynthesis and metabolism - using carbohydrates for fuel - has no net contribution of oxygen.
2. [Photodissociation](https://en.wikipedia.org/wiki/Photodissociation). In the upper atmosphere, ultraviolet light splits water molecules into O2 and H2. The H2 is lost to space, being too light to be retained by gravity, and the O2 is retained. This is why, for example, both Venus and Mars have highly oxidising environments (Venus via SO4, Mars via [perchlorates](https://www.space.com/21554-mars-toxic-perchlorate-chemicals.html) and Fe3+). Note that both Venus and Mars lose H2 more readily than Earth, but still, this process produces significant amounts of net oxygen on Earth.
So.. Any planet with water oceans will have some oxygen production via photo-dissociation, even with no life.
The question is, will this oxygen accumulate? Well, we can see from the Early Earth what happens, even with photosynthesis: Oxygen cannot accumulate until all the available Iron (II) has oxidised to Iron (III) in the oceans and near surface. On Earth, this process gave rise to the [Banded Iron Formations](https://en.wikipedia.org/wiki/Banded_iron_formation). As long as this process is ongoing, there will be no oxygen in the atmosphere, even with photosynthetic life.
[Answer]
>
> will the presence of large volumes of water inevitably result in some of the oxygen making its way into the atmosphere?
>
>
>
**No**
The Earth has oxygen in its atmosphere because of cyanobacteria which produced most of earths oxygen through photosynthesis. However, your planet has "has no native life forms". Without any kind of life, it would be very unlikely for your planet to have oxygen.
Sources:
* [cornell](http://curious.astro.cornell.edu/about-us/63-our-solar-system/planets-and-dwarf-planets/comparisons-with-earth/263-is-there-oxygen-in-the-atmospheres-of-other-planets-intermediate)
* [Scientific American](https://www.scientificamerican.com/article/origin-of-oxygen-in-atmosphere/)
[Answer]
You don't have a problem.
Not only is free oxygen only produced in large quantities (so far as we know) by life, but also, once produced, oxygen is extremely reactive.
To explain why that's important - on earth, *even after it began being produced by life in world-changing quantitites*, it still took something like a billion years for oxygen to start gathering freely as O2 in the atmosphere. Before then, (almost?) all the oxygen produced, simply reacted with iron in the earth's crust producing banded iron ore (or other reactions and combinations, or dissolved in the seas), instead of gathering in the atmosphere.
It takes quite a lot to get oxygen in the air :)
[Answer]
A lot of great info and input here but, to answer the question yes, you can have a planet with no oxygen or very little and still have water. Just because there is O^2 in H20 does not in any way mean there needs to be oxygen around it to thrive. There are planets in existence that have water or ice but no sustainable oxygen or plants to produce or sustain life. For example: <https://gizmodo.com/5887003/hubble-discovers-a-new-type-of-world-made-of-water> and there is not oxygen to sustain life on this planet as of yet that we know.
[Answer]
To add to other answers, consider [comets](https://en.wikipedia.org/wiki/Comet). Whether you call them a "dirty snowball" or a "snowy dirtball", the common feature is frozen water. As a comet approaches the sun, heating will somewhat melt the ice and cause gas jets to be emitted, but this does not result in any permanent atmosphere, never mind breathable O2.
[Answer]
**What's the air pressure?**
Humans don't only need oxygen in the atmosphere to breathe, we also need just the right amount of air pressure. If your world has Earth like 20% oxygen atmosphere and a sea level air pressure of 30 kPa (0.3 atm, lower than air pressure at Mt. Everest summit), the air temperature could still be a balmy 80°F (26.6°C) but no one would be able to breathe. On the plus side (for steam powered devices), water would boil at around 122°F (50°C).
Conversely, you could have too much pressure. Again with 20% oxygen and 340 kPa (3.4 atm), humans would suffer from [oxygen toxicity](https://en.wikipedia.org/wiki/Oxygen_toxicity). This would push the boiling point of water to around 280°F (140°C).
In case it was unknown, humans could easily [survive at these different pressures indefinitely](https://history.nasa.gov/conghand/mannedev.htm) if we're introduced to them slowly (and obviously with the correct oxygen content in the air). Humans only really get in trouble from quick changes in pressure and at the extremes of pressure.
The high pressure case makes the breathing apparatus a bit easier. You just need to reduce the oxygen percentage, which can be done passively.
[Answer]
See Hal Clement's novel "The Nitrogen Fix" where a ecological catastrophy removes all O2 from the atmosphere.
[Answer]
I think that you received great answers to your question but there is something that you should take into consideration.
It is in my opinion very unlikely that a planet with oceans, similar to Earth's ocean, would not have any type of life. Water is important to create life and therefore, there will probably be a type of life present if the temperature isn't freezing like on certain moons. There is life pretty much everywhere on our planet and it doesn't always depend on oxygen. As pointed out before, oxygen is a byproduct of living organisms and the concentration that we have today is linked to biochemical cycles. So, you may have a planet without any dissolved oxygen in the ocean that has life based on an energy source such as sulfur.
Also, you can have oceans that are not made out of water. Matter can be found in different states and pressure as well as temperature may change a gas to a liquid or solid to a gas. It may be a point to consider...
] |
[Question]
[
When we place castles on our fictional maps, lots of effort is often made on how to make those castles virtually impregnable. Walls, moats, defensive weaponry etc.
But one aspect is often overlooked in fiction: How much use is my super-strong castle really?
The purpose of a castle is to
* protect people and goods inside
* stop travellers and armies passing by
* project power over the surrounding land
As to the first point: sure I can escape into my eagles nest and be relatively safe as long as supplies last. But unless I have a sizable force at my command, this only means I imprisoned myself. Really, this means using up lots of resources just to postpone an inevitable defeat scenario. A paranoid tyrant might build one, a wise general would not.
Note, I'm talking "pure castles" here. Walled cities are certainly useful where bandits roam, but typically no way near as strong as a castle.
The second point is very valid if my castle is placed at a strategic chokepoint, a bridge/ford or a pass. It makes a hostile invasion very costly since the castle must be taken for the army to pass. But unless I have such choke points, the value of a castle drastically lessens.
Finally to projecting power. It is not really the castle that does this, it's the garrison. The main advantage which a castle gives is that my soldiers can rest protected inside, while any insurgents outside always must be alert.
This only works against an inferior force though. If the enemy has set up camp close to your castle (but out of range) your soldiers are quite useless. He does not need to storm the castle, since time is working in his favour.
So, to the question:
Obviously castles were deemed useful in the real world, so they do have merits.
Is there a good reason to build really tough castles unless their position is very strategic?
How can I make it necessary for an opponent to storm my super strong castle rather than just passing by just out of range (leaving a small guard to keep the defenders inside)?
Tech level/magic should be quite unimportant here. There is a certain range outside which defenders cannot attack from within the castle. An attacker can besiege or storm a castle, but storming would mean heavy losses.
[Answer]
## TLDR: It's a matter of cost: building castles costs a lot, but assieging a castle also costs a lot. However, you need to control the castle in order to secure your supply line and/or control the region.
>
> As to the first point: sure I can escape into my eagles nest and be relatively safe as long as supplies last. But unless I have a sizable force at my command, this only means I imprisoned myself. Really, this means using up lots of resources just to postpone an inevitable defeat scenario
>
>
>
Thing is, sieges cost more for the attacker than the defender. You have to outnumber the defender if you want to assiege him properly, either by force or with time. So, yes, you **will** consume food and water, but so the enemy. And while you have lot of cereals, dried meat and stuff in your castle and have to feed a small garrison, the enemy has to forage in the countryside to feed a tenfold larger army.
>
> But unless I have a sizable force at my command
>
>
>
Both your army and your castle match your power. You can't have an impregnable castle if you are a petty count. You can assume that someone who can afford and maintain a castle, whatever his size, can also handle a garrison.
>
> The second point is very valid if my castle is placed at a strategic chokepoint, a bridge/ford or a pass. It makes a hostile invasion very costly since the castle must be taken for the army to pass. But unless I have such choke points, the value of a castle drastically lessens.
>
>
>
As you said, if the enemy army **needs** to control the castle in order to go beyond the castle, such a castle makes sense, but I disagree that the value of a castle **drastically** lessens otherwise: if he didn't want to go beyond that castle, it means the enemy wants to control your region. Again, in this case, a castle makes sense.
>
> Finally to projecting power. It is not really the castle that does this, it's the garrison. The main advantage which a castle gives is that my soldiers can rest protected inside, while any insurgents outside always must be alert. This only works against an inferior force though. If the enemy has set up camp close to your castle (but out of range) your soldiers are quite useless. He does not need to storm the castle, since time is working in his favour.
>
>
>
Having a castle is really great to harass an army, either by attacking the rear, or even better, cutting the supply line. Military logistics such as "how to feed an entire army, several km away from its country" are often underestimated.
And if you are the inferior force, good for you. As stated before, it will cost the enemy much more than you, and some sieges can last for several years.
How useful is an impregnable castle? Tremendously useful. However, not everyone could build one. It's a common fantasy trope to build a much bigger castle than historical ones; it's up to you to see how big castles are in your world. But they will be useful
[Answer]
Castles were useful for a certain type of defensive warfare. They allow you to project power over an area with a relatively small but immobile force. You could consider them to be primarily a delaying tactic, designed to hold up the enemy until such time as a significant force could be brought in.
A good castle can be the deciding factor when a smaller force is defending against a larger one. If you have a larger force and a castle, then you don't retreat to the castle, you engage in battle.
Some groups decided that castles weren't so useful, during one of the Scottish rebellions they realised that for their style of highly mobile combat, castles were a trap. They demolished any that they took.
Remember that the difference between an impregnable fortress and an inescapable prison is the side of the doors that the locks are on. Or in the words of the immortal General Callus Tacticus (Terry Pratchett):
>
> After the first battle of Sto Lat, I formulated a policy which has stood me in good stead in other battles. It is this: if the enemy has an impregnable stronghold, see he stays there.
>
>
>
If you have retreated to your castle with a larger force then the attackers should do their best to ensure that you remain inside.
In extremis you play the siege game, where the stores of the castle are played off against the logistics of the attackers, but you really don't want to do that if you can possibly avoid it. If your force is too small and the enemy large with good logistics, your castle will become your prison, and ultimately your grave.
---
Kings build castles, they're a statement, a fortress, a garrison, an armory, a prison. These things are all useful in their place.
Generals do not build castles, they want to be mobile.
[Answer]
Standing army is expensive. Both in money and in supply.
Any medieval lord had a very limited amount of resources at their disposal at any given moment in time. Combined with the terribly inefficient logistics of the time, in most cases they just can't afford to keep the army in the field for a prolonged period of time.
For instance, in 1066 king Harold effectively crushed the Norwegians at Stamford Bridge, but had to disband his army immediately after that (even despite the ongoing Norman invasion!) as he was not able to keep the army supplied for long enough.
While sitting inside your fortifications, you slowly spend your resources. Your enemies, however, spend their resources at a much higher rate as they have to keep a larger force in the field.
This means that you don't need to sit in the safety of your eagle's nest forever. You just need to wait until their vassals get tired, their coffers get empty from paying mercenaries for just being there, their soldiers start to desert in masses because of hunger and diseases, which will inevitably spread in their camp as they have no idea of sanitation. And this will happen very soon.
[Answer]
Castles were built in strategically relevant locations for exactly the same reason you point out: physically control a road, a river, a border, a lake when there are little or no alternatives for an ill intended opponent.
And that was also the reason why they were often dismissed: once the strategic reason is removed, they become a monetary bleed.
So, no, nobody sane would build a castle in a location with no strategic relevance. If you cannot force your enemy to attack the castle, you cannot use the castle to chase your enemy.
If instead the military usage is not the main scope of the building, the location can be chosen at leisure: see [Castle Neuschwanstein](https://en.wikipedia.org/wiki/Neuschwanstein_Castle).
[Answer]
Castles are useful for defense of the land. It's really hard to take over a piece of land if, in the middle of the night, you could get slaughtered by soldiers whose entry you couldn't prevent because *they live there*. They're already on the land, so you can't keep them out. You can't drive them out, because they can retreat to their castle, which is a privilege you can't afford. You can try to take the castle, but that will inevitably lead to problems.
You can hold out for a long time in an impregnable castle. Plenty of food, a source of water and any other provisions mean that it would be incredibly costly to try to take over your territory. An attempt to overwhelm the castle quickly would be stupid: you could murder them from above while they hammer away ineffectually at the walls.
If you want to take over somebody's land, you basically have to take the castle- otherwise you'll have to perpetually defend against its soldiers. An impregnable castle makes this very difficult.
Also, imprisoning yourself inside the castle means that nobody is working the land. The entire region shuts down and becomes useless.
A strong castle is a way of concentrating all the value in a large, indefensible area into one impregnable stronghold so that it can't be stolen. The knowledge that this would happen is enough to deter would-be invaders.
[Answer]
## Walking around the castle has its costs
As you mentioned the enemy has an option to simply walk around, however if they do so they dont have much of a choice in leaving force strong enough to keep your garrison inside. If your garrison was allowed to roam freely, they could disrupt the supply lines, which is something you dont want to allow.
There are high requirements on such force - first of you need to outnumber the defenders 3 to 1, preferably 5 to 1 in order to discourage defenders from trying anything. In addition you need some men to pillage the country to keep the siegeing force supplied. There is also the requirement of at least decent morale and loyalty - you dont want *all* of your soldiers to wander off to pillage giving defenders option to overpower the spread out forces.
## If you had a dozen castles
If the bulk invading army consisted of 30 000 men and you had 12 castles with garrison of 200 men each, your castles could lock easily total 10 000 of the invading force in stalemate below their walls. Easily doubled if you had the time to reinforce said garrisons.
In addition, having a multiple of castles on the way to your capital would significantly weaken the main force not just numerically. Main force would be more vulnerable as *any* of the besieged garrisons could find a way to get rid of the attacker at any point of time (a distant vassal coming to help) flanking the main army, disrupting supply lines, freeing other garrisons or finding any other way to make main army life more complicated.
Another consideration is they cant just leave the pleb guarding your garrisons - as mentioned above they would most likely wander of plundering countryside. Fair share of the force left behind would need to high morale units with minor commanders with them making the numeric loss even more significant.
[Answer]
* **Castles as Fortified Garrisons**
Some castles would be built to hold down the population of a restive province. They provide a base for the "occupation" forces sent by the "central" government or by a foreign power. A strong castle can be held by a relatively small garrison, so once you have built it the mobile forces can either be reduced or sent out on patrol.
* **Castles as Fortified Manors**
Some castles were built by a local ruler to protect his property and that of his subjects against intruders or serf uprisings. In a castle, a relatively small garrison could defend the household of the lord and possibly even the serfs and their livestock.
* **~~Castles to hold Chokepoints~~**
There was some of that, but a castle could not project power beyond the range of a catapult or early cannon unless it also had a mobile force, which would make this the first bullet point. A somewhat related issue might be **castles as bridgeheads**, when one end of a bridge or perhaps both are fortified. But that't not an independent castle, more an outer works for the city on the other side of the bridge.
So castles have the same purpose as the much-maligned [Maginot Line](https://en.wikipedia.org/wiki/Maginot_Line). They allow a small permanent garrison to hold a larger enemy off until more of the own forces can be mobilized.
* **The Defender has Height and Cover**
When most weapons are muscle-powered, standing on top of a high wall has distinct advantages.
* **The Defender has Interior Lines**
That means the besieger might need more troops to [circumvallate](https://en.wikipedia.org/wiki/Investment_(military)) the castle than the defender needs to hold it.
* **The Defender has Housing and Supplies**
Sure, a castle under siege is not a healthy place to live, but a medieval field camp is even more unhealthy. More besiegers than besieged might starve and get sick. Also, armies marched much slower than a single messenger. So the defender probably had time to gather extra supplies from the outlying villages, while the invader has to bring them over a long distance -- all nearby supplies were moved into the castle.
[Answer]
You want your enemy to try **storming** your very strong castle even if it is not strategically placed, or at least you need to gain something by building that huge and strong fortress.
But castles are not only useful for this. First, understand your super strong castle **controls your territory**. Your enemy may **destroy** whatever it likes and **plunder** every village on the way to your castle.... yet, **the territory will not belong to him** while there is that super strong fortress and its **garrison** inside it. His peasants will never have the opportunity to **harvest the land**, his merchants will **never travel safely**, nor would he be able to **exploit mines, forests, or rivers** in the region. Basically, while your super fortress is still standing, **the game is not over for you**, and this war brings almost nothing for the attacker, expect **wasting his time and gold**.
That's why castles were useful even for the small nobility, willing to **protect their independence** from their peers. Without enough forces to besiege that castle, and hold the land, and protect his own land, **no other lord would dare attacking you**, because if he did so, he would lose a lot of men and money just to take your land. Making him quite **weaker indeed**. Probably weak enough to become a prey for small neighbours willing to take the lion's share.
Modern video games do quite a good job to show it. I'm thinking of the Total War and Crusader Kings series. It is easily seen in game, that **even a small enemy can be a tough nut to crack** when he has a strong fortification. Of course, you can ignore his army and plunder his land. Of course, you can besiege it for years and lose men by hundreds before taking that tiny city. But if you ignore it, then **one day his army will come out of the castle**, and attack your own village. It will not defeat you, but if you are at war with someone else, you will lose **a lot of time**, and an important part of **your economy**. If you besiege it, you will lose a lot of time and perhaps a lot of men. You could even end up in another war, because your neighbours can see you lost troops and are now quite weaker.
In such games, without strong fortifications, the small country's army could just be crushed in an open ground battle, with much less losses, while grabbing the land easily.
That's the point of view of the tactician. Now on a much larger scale, if you don't limit your view to your own castle and to a small war, having such a stronghold is a big thorn in the toe for any invader. Your stronghold, if not taken care of, can:
* Disturb supply lines
* Disturb communications
* Conduct guerilla warfare, while benefiting from an unassailable lair to rest and rearm
* Secure some critical resources
* Act as a strong bridgehead for any future counter attack
* Secure the flanks of any allied army
* Act as a supply depot for any allied army
And so on.
If taken care of by your enemy, then your stronghold still grants benefits in a campaign by :
* Tying down enemy forces, **much more forces** than what's needed to protect your stronghold
* Gaining time, because such forces will need an invasion force to plan what to do, to **split up forces**, organize a good siege before leaving. Or else, we're back to **"Your stronghold is not taken care of"** if the invader does not set a good besieging force.
* Win the **economic** war. Your castle is a strong asset, it took years to build and cost a lot, but will last for tens of years. When the war breaks out, you most likely have to spend very few bucks on your castle. However, your enemy must still spend money for all these men besieging you. Each passing day, he loses money. Each day that passes, your castle is more and more profitable. In the middle ages, a professional force cost a lot to maintain, good weaponry is incredibly costly, especially for good steel, and these men aren't going to fight for free.
* Decreasing efficiency of the enemy's **chain of command**. Your stronghold doesn't need many qualified men to hold its ground. Mere sergeants are enough to motivate the troops, even though qualified officer might help. However, besieging a fortress requires at least one or many experienced **siege engineers** and/or **officers** to know how to set up the forces, prepare for sorties, prepare their positions in case an external army come to break the siege and so on. In your case, your castle is already built, and it was built by the very same qualified people your enemy now needs to besiege it. You have these qualified people at your disposal to do whatever you want, while your enemy must leave irreplaceable assets behind.
* Your strong castle might be one out of a strong network of castles, forcing your enemy to leave one castle at a time a small force to besiege it, weakening slowly its army. Should your own fortress be too weak, your enemy could storm it immediately. Here, having an impregnable castle is important.
I hope it will help you. Just remember though, do not fall for the classical **Maginot** trap : your stronghold will never be invincible, and an enemy might still want to avoid it, even though it means all the points we saw earlier. Thus you must take that into account, and perhaps even build your own strategy around it. A strong enough fortress might deter anyone to attack you, deflecting any invader to a less protected region.
That's what some modern days fortress were meant to be in Belgium, France, or even Switzerland, and some did their job well. Maybe that's what you truly need.
[Answer]
## Impregnable fortresses/castles don't exist.
What a fortification is meant to do is delay the enemy, so that defenders can get their acts together/evacuate the civilians, before they are overrun. Historically, any group that has relied exclusively on walls and fortifications has lost, as their opponents, simply walked round the wall, e.g., the [Great Wall of China](https://en.wikipedia.org/wiki/Ming_Great_Wall) or the [Maginot Line](https://en.wikipedia.org/wiki/Maginot_Line).
You therefore need two things to have an effective fortification (or castle, in your case).
1. The enemy must be willing to attack it, rather than avoid it. A reputation for being impregnable is a demerit.
2. The capacity to last long enough for reinforcements to arrive, and hopefully, do some damage to the enemy in the meantime.
Ideally, your defensive structures should act as a funnel, controlling your attackers' mobility. You get to control how fast they can move, and what routes they take. Impregnability isn't needed.
[Answer]
**One does not simply build a castle**
A complete castle is a formidable structure indeed, but its site was strategic *before* it was there.
The building of a castle is an organic process. It might begin with a simple campfire, then perhaps a wooden wall, a lookout tower, an armoury, a barracks, etc. Maybe there is a day when the wooden walls are replaced with stone walls.
The strength of a castle is dependant upon the strength of the attacks. If attacks are frequent enough, then the nobility will keep home there, and perhaps there will be a place to trade.
The castles that exist in present time exist simply because they were not in a strategic place during a modern war. They have become symbols of wealth and tourist destinations. Many have been built up bigger than they ever were while they were functional castles for those reasons alone.
[Answer]
Tidbits to add to the fray here:
Castles require a garrison. Indeed there is a fairly close ratio between the length of the outer wall and the number of men required to defend the walls. Clever use of natural features (lake, river, cliff) could reduce the wall to be defended.
Because they require a certain number of men per furlong of wall, castles were made as small as possible and still function. Not all were tiny, but the tradeoff between interior space and manpower requirements were carefully considered. There is some advantage to larger castles: Room inside goes up with the square of the diameter, while the amount of wall goes up only linearly. But you don't want a castle that requires every able bodied man for 2 days travel to man the walls.
Disease was a big thing in siege warfare for both sides. Let typhus run through the besieging army, and you could get a much weaker opponent without loosing a single arrow.
[Answer]
Your question is in two parts. First, why build a monster of a castle someplace it isn't strictly necessary, or strategically sound. Second, why would an enemy be bent on getting in when it may be easier to sit and watch you starve.
I think politics is a good answer to both. First, a castle isn't only a fortress, but a statement of intent, of power, and status. I do disagree that the garrison is more important than the brick and mortar. Suppose you are a warlord and have in your possession a very nice pile of gold. What to do with it if you aren't planning on going off to conquer more land? Invest in something very visible to tell your neighbors not to screw with you.
You build it because you can, because someone who could build a giant castle next to an unimportant but very pretty lake is someone who has power and status. The bigger the castle, the more materials used and the better maintained it is, the more others will know of your vast wealth and vigilant oversight - both being important factors when considering the strength and smarts of your opponent or rival. You make the castle strong because that's just being professional.
Alternately, the position of the castle is not *strategically* important, but culturally important. It is a symbol of power or tradition. Whoever holds it hold the honorary position as its steward and that grants political clout.
The second question is why would an enemy need to attack directly. That could be answered by what you have within your walls. In the game of warlord politics, power comes both in strength of arms and in legitimacy to rule. You (the attacker) may have the bigger army, but that stupid castle holds the family that has ruled this land for generations. Even if you pen them in, there's always a chance they could stir something up. They could escape and raise an army, or someone may try to assassinate you to put them back in their rightful place. Maybe your next target will get important time to prepare, or a neighbor is preparing to attack while you're busy picnicking in front of a foreign castle. No, a smart warlord breaks down that castle to end their rivals just as soon as they can so they can get on to other things in peace.
Winter is coming, too. You have the advantage now, but if the snows come early, your men will starve and freeze outside of that castle. You can assault it now, end the threat and have a nice warm home for the cold months, or you can pull back to your own encampment. In the mean time, though, the winds could change. Messages could get in and out of the castle. New allies for your enemy could appear, and you may not have the advantage again.
If the attacker isn't playing the plunder and pillage game, but politics with the intent to control the land and rid themselves of their rivals, a castle holding their rivals would present a huge obstacle and threat to their ambitions, as well as being their main target. Once military and political opposition is eliminated, they can do whatever they came here to do. There may need to be a ticking clock to encourage a storming of the castle rather than a siege. Other events occurring, movement of another rival's armies, etc., or even the weather changing could make an attack imperative. If the leader believed they could lose their advantage if action isn't taken now - and they need something in that castle ASAP - a storming may be in order.
[Answer]
There's a lot, like a LOT of good information here, so I'm going to try to cut straight to the heart of the question:
Question: Is there a good reason to build really tough castles unless their position is very strategic?
Answer: Yes. The primary reason would be to protect something that can project power REGARDLESS of where it is. There are all kinds of examples of this sort of thing. For example, a symbolic authority figure can have a HUGE impact just by staying inconveniently alive when other people would like to kill him so that they can usurp that authority. People like Nelson Mandela and Ghandi for example projected ENORMOUS power even when they were imprisoned in someone ELSE'S castles.
Less symbolic examples would be repositories of information that are not accessible anywhere else, or weapons with intercontinental (or interplanetary) ranges. Said weapons could run the gamut from nuclear weapons to information warfare tools that just require a satellite feed.
For that matter, you might need a strong fortification just because it's Not Safe to live anywhere else. In a sufficiently apocalyptic environment you might need a castle (or equivalent) to survive onslaughts of zombies, vampires, werewolves, or even sufficiently extreme weather.
[Answer]
Castles were often just mansions of medieval Europe.
But the point being, Why would you hole up in a castle? So someone could come and save you. As long as you're keeping your enemy at bay you can await reinforcements from friendly troops.
Of course time periods and definitions of castles effect the answer a lot. Many castles were quite small, basically being a status symbol and a place to hide if someone tries to kill you.
But the earlier definitions of castles are actually more like forts, towns with defensive perimeters to protect them from foreign invasion.
Larger castles belonging to Royalty were usually a status symbol passed down through the family, though it also had plenty of rooms inside to provide a variety of activities for the royals inside.
As far as a super strong fortification, I would recommend an enclosed city, where the wall is the main fortification, not the castle. There would be room for soldiers to defend, and if some amount of land was inside at least some food could be produced, hopefully waiting out a siege in a war of atrophy. Only the most important cities would need this though.
[Answer]
Ancient and medieval warfare had none of the speed and mobility of today. Marching your army from your capital to the battlefield could take weeks or even months.
That means if you do not destroy the enemy, as soon as you leave he will regain control of the lands you just conquered and everything was for nothing. If the enemy retreated into a castle, you had no choice but to besiege or assault. Yes, you could leave him there and take control of his lands, but sooner or later you need to leave (home or to other battlefields).
Castles could and did tie up an enemy army for **years**. That means you cannot conquer someone else in that time, you need to supply and pay your army for that time, and very often you yourself had to be in the field and run your kingdom from a tent for that time. All of these things are a **major** nuisance.
The utility of a castle is not what you can or cannot do while in the castle. The utility is that it preserves the army and means if the enemy leaves without taking the castle, within a day or two everything will be back to what it was before he came and all his warfare was for nothing.
[Answer]
Some additional uses for a castle:
**Keep your treasures in it**
Every ruler has some things he really does not want to loose:
* his gold and silver
* his documents
* his wife and more importantly, his heir
* his court mage
* his lover...
If the enemy could send a small raiding party and destroy or take these things while the ruler is busy fighting the main invasion force, it would be a great problem. He can fight bolder if he knows that his loved ones and most priced possessions are safely in a strong castle.
**Weather invasions of nomadic horse-archers**
Nomadic hordes can sweep punny feudal armies from the field. But they usually suck at besieging castles. Indeed, castles are so useful against them, that after the Mongolic invasion of 1241, King Béla the IV of Hungary started issue land grants on the condition that the recipient builds a stone castle on it.
**Create a defensive area of hundred of kilometers depth**
All the blue and black crosses on this map are castles built by 15th century kings of Hungary to defend against the Ottoman Empire. It took about a century for the most powerful land army of the word to get past it:
[](https://i.stack.imgur.com/ywWpW.jpg)
A single castle is good, but a in-depth defensive belt of many strategically placed ones is even better: Frontier pasas can not simply launch expeditions deep into Hungarian territory. The full mobile army of the Padisah has to come, but since it assembles deep in the south and marches long through the Balkan, the King has time to assemble a counter-force. And even if the Ottomans take some great castles, the defenders still can try and get them back after they have left, or simply build new fortifications before the next campaign season.
And remember, this was **after** the invention of firearms, and many of the castles were only wooden fortifications.
] |
[Question]
[
This question:[Why would a language be untranslatable by universal (machine) translator?](https://worldbuilding.stackexchange.com/questions/61954/why-would-a-language-be-untranslatable-by-universal-machine-translator) inspired me to consider, if one possessed a universal translator, is it reasonable to consider that it could be used to translated an encrypted message? Of course, it could be expected that if a UT could be used for decryption, that those encrypting would devise a way to thwart the UT, but could the UT be used to decrypt more primitive forms of encryption, such as an enigma machine generated encrypted message?
Edit: The question was asked as to how it would work. How I perceive it, it would have a complete understanding programmatically of how we communicate, in all forms, with updates when we find new ways of communication that hadn't been conceived before.
Edit #2: How it would work when encountering a language previously unknown is internally, it would look for similarities to known languages and if it finds a similar language, it would apply the rules of that language, until those rules fail, then seek another language that has a more successful rate of translating, and use that, repeating this testing until it finds one that best matches. In the event no known language matches satisfactorily, it would then apply rules of language structure...common words and phrases, until it finds a structure that works and use that. I am not a linguist, so I do not know if there are other tests. If there are, then they would apply, all programmatically. If all tests fail, then it would request additional information or wait until additional data was received...such as further conversation, or a chart of common words.
But, that is not what I am looking for. What I am looking for is, using whatever programmatic format, can a UT identify code?
One more point about changing encryption. It could be possible that a language changes pronunciation in a similar manner. That is, whatever encryption you envision could be the natural language of somewhere.
[Answer]
# No
I will make the assumption that the universal translator generates a consistent mapping from words, expressions, or idiom in one language to another. I would also assume that it uses samples of language to map potential meanings onto any phrase or sentence, and through some super-advanced algorithm, quickly discerns the meaning of what is spoken.
The problem with cryptography, in this context, is that there is no direct mapping of a word (or expression, or idiom) from one language to another. If I say something, and public key encrypt it, and then you say the same exact thing and encrypt it, those two statements might not be the same thing! Their encoding depends on the user's key. Furthermore, if I say something today, and then the same thing tomorrow, when encrypted those won't necessarily be the same thing either!
The problem with encryption, is that there is no consistent 'language' to be translated. There cannot be a map of a concept like 'blue' to a discrete subset of an encrypted message. 'Blue' could potentially be encrypted any way, depending on what specific cypher is being used that moment by that user.
Therefore, based on the assumptions of how a Universal Translator works that I started with, the Universal Translator will not be able to translate an encrypted message.
[Answer]
An encrypted data stream is statistically indistinguishable from a purely random stream, at least a data stream encrypted by a good encryption algorithm. Since the encrypted stream cannot be distinguished from a random stream, there is no structure on which a universal translator could work. If the encrypted data stream *can* be distinguished from a random stream then the encryption algorithm is broken; we should expect that when we will be smart enough to build a universal translator we will also be bright enough to write decent encryption algorithms.
[Answer]
The answer is unfortunately simple:
**There are no universal translators in real life, so the capabilities of a fictitious universal translator in a story are 100% defined by the author's choice of such capabilities.**
Thus the answer to this is plain and simply "whatever you want it to be." That being said, there would be some requirements on a UT that can decrypt encrypted text.
* It needs to be effective at reading between the lines to find the true meaning. What you are describing would only make sense if the translator tries to find the real meaning of things, not just what is said. A translator that can unmangle enigma encoded messages would be able to read between the lines for a hapless male character who is obliviously missing the hints his wife is giving him. (come to think of it... can you make me one of these!?)
* The mere fact that it is possible to translate such meanings should suggest that there is some degree of commonality between all languages. In linguistics, it is not known whether such a commonality exists. Chomsky famously suggested that the concept of recursion was universal to all *human* languages -- a so called "[universal grammar](https://en.wikipedia.org/wiki/Universal_grammar)." Strange human languages such as the Pirahã language make it difficult to argue this commonality exists in humans. Commonality between sapient species is beyond that, and in the realm of the author.
[Answer]
One important aspect that all naturally occurring (and some invented) languages have in common is that it has native speakers who learned the language by listening to it. I won't go so far as to say that the languages were "designed" to be learnable, but any language that isn't human-learnable wouldn't last very long.
Encryption, on the other hand, is specifically designed so that a listener who doesn't know the encryption will be unable to decipher it.
A translator that is designed to be able to learn like a human (no matter how much accelerated) won't be able to crack encryption (and the encryption being cracked is crackable by one or more of its algorithms) unless the ability to crack encryption is specifically included, just by virtue of this difference in "design" of language and encryption.
EDIT: This doesn't even go into the technical side of why encryption is difficult to crack, which is a much bigger question (and mostly irrelevant once you consider the above).
[Answer]
No.
This extends on some other answers going into more details, but the short summary is that every language by necessity has **patterns**. A grammar, a fixed vocabulary, semantics, all of that. A well-encrypted data stream should not have any meaningful patterns, it is indistinguishable from noise or randomness.
A universal translator by definition does not have a database of languages (it wouldn't be universal, or the database would have to be infinite), but rather "learns" a new language it encounters. The only way to do that is to somehow (handwaving) decipher the patterns in the new language. On an encrypted data stream, it would not have any patterns to identify, thus it cannot translate/decrypt it.
---
Even shorter answer:
No, translation and decryption are completely different processes with different rules and methods, and a system capable of one isn't automatically capable of the other.
---
Finally, answer with caveat: When you go into the realm of very, very simple encryption (Ceasar ciphers and other substitions), then yes your translator would be able to translate encrypted messages, because these primitive ciphers don't hide the patterns. Which is exactly why they are so trivially easy to break that you can do it with a pen and a sheet of paper.
[Answer]
One thing that wasn't mentioned yet is that a universal translator would be perfect for codewords and code phrases.
A codeword or phrase is basically a substitution for a normal word or phrase, for example a "tank" could be called a "can" and killing someone could be "taking out the garbage".
A universal translator could pick that up as a local dialect, synonyms or sayings and then automatically start translating them not even knowing it was meant as a code.
[Answer]
## Universal Translator as a cryptanalysis engine
The proposed concept isn't that far fetched. It's worth noting that the field of machine translation starts with this quote:
“When I look at an article in Russian, I say: ’This is really written in English, but it has been coded in some strange symbols. I will now proceed to decode’” (Weaver, 1955)
Any non-magic implementation of an Universal Translator *must* be a de facto cryptanalysis engine that attempts to divine a decoding process for a previously unknown communications system, given some sample data.
It doesn't mean that it can magically start solving unsolvable problems. Secure modern encryption algorithms are not vulnerable to analysis that a non-magical UT can perform. The following styles of encryption *should* be in scope of what any UT must be able to do to be UT:
* All the various styles of substitution ciphers - they map directly to translation problems between e.g. text in different alphabets;
* Many approaches of steganography - detecting which parts of observed behaviour are relevant for the language (e.g. is meaning communicated by the pitch shifts in sounds coming from the vocal tract, the twitching of the eyes, or both?) is comparable to the problem of detecting hidden messages in large data streams;
* repeatable block cipher analysis - mapping fragments of noise to units of meaning, given vague data and guesses about what it might represent is comparable to breaking <https://en.wikipedia.org/wiki/Block_cipher_mode_of_operation#Electronic_Codebook_.28ECB.29> ciphers.
However, language (no matter how alien) is substantially different from an encryption system in that it is meant to be *understandable* and *learnable*, either explicitly designed so or naturally evolved towards that. Properly designed and used encryption systems do not leak information that can be used to learn it, so a non-magic universal translator doesn't have available data to learn from.
[Answer]
This sounds like a sword and armour problem.
A sword that can cut through any armour forces the design of an armour that can't be cut through by any existing sword, which forces the invention of a sword that CAN cut through that armour, which forces the design of better armour,....and so on.
Similarly, a translator that can decrypt encrypted information forces the design of better encryption algorithms. Now, unless the translator is specifically designed as a snooping tool, that's where it stops, otherwise you get an encryption arms race.
The answer, for a legitimate device, would be NO.
[Answer]
I am the one that wrote the encryption concept in the referenced link.
My intent behind the idea that a language could EVOLVE with a natural encryption, not necessarily a digital or binary type encryption. While I was considering the idea, I was thinking of a reason why encryption would be required... and I imagined a society that only communicated via sonar or pheromones in a crowded space. In order to separate conversations from the noise of other conversations, a natural encryption system was developed. The parties involved in the conversation had the key to decode, and everything else that was indecipherable was just considered background noise.
**To Answer the Question:**
**Yes**
I believe that it would be well within the ability of a Universal Translator to decrypt KNOWN encryptions, especially ones that were created dozens/hundreds of years ago.
This knowledge base of encryption techniques and strategies could just as easily be applied to new variations, and would require much of the same logic, analysis and intuitive leaps as parsing a newly discovered language. Many of the same problems would apply too... for example, not having enough data (short message bursts), limited reference points, design of encryption too unique (grammar), limited ability to extract meaning, etc.
Ultimately the UT is an AI computer and would not give up (humans might stop the processors at some point though). Eventually given enough data and processing power the UT could crack the encryption.
However, I wouldn't necessarily make such encryption breaking UTs available to the general public... it would be in the hands of government, military, etc.
Often in history, encrypted communiqués are decoded but their information may no longer be viable or valuable past a certain period of time (such as in military operations).
Do not expect that your currently encrypted data will be safe in 10+ years unless you continually update it with the latest technology.
[Answer]
IT-guy here
Depends on the encryption-scheme in question. For keyless encryption-algorithms it's pretty trivial, since every word can be directly translated into an encrypted word and vice versa. As an example one could name [ROT13](https://en.wikipedia.org/wiki/ROT13).
For encryption with keys, things become at least hard to impossible. Consider for example the [Caesar-Cipher](https://en.wikipedia.org/wiki/Caesar_cipher), which is basically ROT13 with an arbitrary rotation-offset. The issue here is obviously that we need the key to get a proper result. We can of course guess the key, but this requires a way of distinguishing the correct output from rubbish that gets produced when we translate with a wrong key. This way may exist for certain inputs, but there is as well quite a good chance, that another key results in another text that is valid as well.
For modern encryption-algorithms this becomes even worse. Caesar-Cipher has a key between 0 and 26. AES256 encrypts with a 256bit long key. So on average we need `2 ^ 256 / 2 = 2 ^ 255` guesses before we get the correct key. With a quite good chance of finding a few other keys that output other "correct" output as well (correct in the sense that the UT understands it). In addition to that, the computation will [take for ever with current super-computers](https://www.reddit.com/r/theydidthemath/comments/1x50xl/time_and_energy_required_to_bruteforce_a_aes256/) and the worldwide per year produced energy would only be sufficient to test out a fraction of the keys. And at that point we haven't even done any testing whether there is a valid output.
So in short:
For keyless encryption-schemes: sure, it's just a simple mapping. For encryption using a key: theoretically yes, but the encryption needs to be extremely weak and you need to be lucky in terms of the encrypted text to get a definite output. For any stronger encryption you need an enormously strong UT (far beyond what is possible with state-off-the-art resources). Additionaly technology moves also on for encryption. E.g. there are already public-key-encryption algorithms in the making that are resistant to quantum-computers. You'll never be capable to build a UT that is able to translate ciphertext that was translated with state-of-the-art encryption, simply because that's exactly what encryption is supposed to do.
[Answer]
**No.**
An encrypted message is, by definition, incomplete.
When you encrypt a message, you then have two pieces that you need to unlock it:
* The key
* The encrypted message
The Universal Translator wouldn't have the key.
Note that the key can be arbitrarily long (eg. [Book Cipher](https://en.wikipedia.org/wiki/Book_cipher)), and if you come up with the wrong key, you could decrypt the message to a completely different result, failing the translation.
[Answer]
## It depends on how the translator is implemented, but probably No.
There are two major categories of translator: *language analysis* (Star Trek), and *mind reading* (Hitchhiker's Guide to the Galaxy).
### Language Analysis
In the case of the former, there always appear to be limits and certain languages are just so alien that they cannot be translated. Example: [Tamarian in Star Trek](http://memory-alpha.wikia.com/wiki/Tamarian_language) and [the Orz in Star Control](http://wiki.uqm.stack.nl/Orz). I think that for reasons stating, if the engine is making a best guess effort to analyze the data based on common thought patterns, then obviously the same limitations that would apply to species that fundamentally reason differently would clearly extend to cryptography, as good cryptography means that no analysis can really be done.
### Mind Reading
If the translation works by directly accessing the mind of the creature speaking, then it could work assuming that the device knows how to directly read the thought patterns of the one speaking. An obvious example of where it would definitely work is if humans had an implant (in their brain or vocal cords) that would encrypt the speech as it's being spoken, and a second implant that would do the translation probably accessing a public key over wifi or some such.
On the flip side, this sort of translation would be extremely unlikely to work (at all) when communicating with sentient robots, whether or not the speech was encrypted.
---
Of course, a translator could be implemented that attempts to use both approaches simultaneously, but clearly it would not work in the case of sentient robots speaking under encryption.
[Answer]
Yes, provided a large enough sample.
To learn a language, an universal translator needs a large corpus of texts in that language, ideally with some information about its meaning. From that corpus it can infer information about the language.
A large sample of encrypted texts with the same keys won't be different. It is just a language with different rules - maybe a bit more complicated - but that rules can be inferred from the sample. In fact, it would be possible for cryptographers to break any code given enough messages with the same key and enough computer power.
[Answer]
in order to translate nuance, subtext and handle contextual meaning a universal translator would have to be an AI. capable of actually understanding the language not just an algorithm. Such an AI would be able to break the simplest encryption (substitution, ciphers, ect) relatively easily, but more advanced encryption would just as hard for it as it would for humans.
If you want really hard science ideally both sides would need their own UT which would communicate together at high speed to learn each language. simply not having one on each side would make it much harder and require cooperation.
[Answer]
## No.
Given an encryption algorithm A and a secret key K, we can map from a string in English to a new string. We'll call this "language" AK. The product of encryption with algorithm A using key K is a string in AK.
`Dog -> [cyphertext]`
Assuming our universal translator is capable of exhaustively trying every possible language in existence, it should eventually try the language AK. This will result in:
`[cyphertext] -> Dog`
However, it's also going to try every other language in existence. There likely exist other keys that result in:
`[cyphertext] -> Cat
[cyphertext] -> [a secret so terrible, the universe is instantaneously destroyed]
[cyphertext] -> [the recipe for Coke]
[cyphertext] -> [cyphertext]`
It'd be possible to reject spurious combinations of A and K with a large enough sample size (we get garbage output that isn't English), but that assumes that we know the language we're decrypting to.
Since we're testing *every language that could ever exist*, we can handle double, triple, etc. encryption - just create a language AK•AK that represents two rounds of encryption, then translate from AK•AK to English. So that shouldn't be an issue.
There are an infinite number of languages, and it's not even possible to recognize all of them with a Turing machine, but we're already assuming the universal translator has gotten past that little computability problem.
So, if you have a universal translator that can do uncountably infinite quantities of work at once **and** is capable of figuring out what a valid string in the target language is, then yes, you can decrypt anything.
..so basically, the answer is gonna' be **no**.
[Answer]
Simply put, the answer goes like this:
An encryption is about turning an amount of data segments (not necessarily words, mind you but we can assume words) scrambling the data (e.g. mixing all the letters together to form one giant word or series of words) applying an invertible numerical transformation to the data (e.g. adding 1 to every letter and shifting it), mixing some more, doing more transformations, etc. Finally the data is sent off and the result is undone. DNA is a good example of encryption. Programs are encryption. Integrals (if you know calculus) are encryptions (because the inverse to a specific integral is always unambiguous). If your translator handles general encryption, this implies your translator can do advanced mathematics, decompile programs and even understand DNA sequences (note: we don't even understand all of DNA). Also, consider that not all programs are writable in the same language. Compilers turn specific languages into specific binary. They can be the same, but they usually have different styles based around the features they use under the hood. Trust me, decompiling would not be trivial.
Now, take your universal translator. Let's assume it can hear and parse a sentence and translate it to your language. A general idea behind languages is that all of them have words and that words are pretty much atomic. It wouldn't make sense to have a language where you cycle between every word and say one syllable in a loop.
In that world the sentence: "An ex-am-ple sen-tence" would be said as: "an ex sen am tence ple". Needless to say, it would be gibberish. Words are atomic. They don't get mixed. Encryption is all about the sub-atomic manipulation. Break the words apart. Mix up the letters. Don't mix the meanings of the symbols of the words. Manipulate the expression of the words, which is where your translator would inevitably fail without a serious upgrade beyond language skills.
Even if your universal translator needs no context, it's a much different problem to solve encryption then it is to translate a language. We can argue that two languages both have a way of expressing "blue". However, encryption distorts this. The phrase "a blue bird" is no longer separable. You cannot look at just "blue". Do this on a large enough scale and you propose a "language" where every sentence is a particular symbol. At that point, expect processors to burn up. Plus, it is expected that languages be spoken in some way. Therefore, the translator learns from hearing, not reading. Anything, not audio-visual is nonsense to it. Converting the written language can be handled differently, and we can assume certain rules. If it fails... well that's just a limitation of the theory of languages and what we expect a language to be, not the device.
to sum it all up:
**Unless you just desire a universal computer calculus solver/DNA parser/assembly code decompiler/language translator... there is nothing that says it must be this.**
In fact, go over to mathematics and ask about mappings from one set to another AKA functions. Your universal mapper (rather than translator) goes from merely universally being capable of determining the one to one mapping of *thoughts and ideas* (aka words) to being capable of determining the one to one mapping of any data set to any data set. In other words, I feed your thing an sampling of a function at different points... it gives me back an exact expression of that function. Good luck dealing with unclosed forms.
[Answer]
Universal Translators as they are depicted in fiction are not something we can explain with science.\* To explain them we need pseudo-science or magic.
Pseudo-science and magic are both capable of breaking any encryption the author wants them to break.
---
\*There may be a few rare stories involving somewhat realistic translators where actual in-depth study of a new language and associated culture is required before the translator can partially translate. However, the common form of universal translators used in fiction only needs to pick up a few sentences of a language before they can translate the entire works of Shakespeare, which is magic.
[Answer]
Depends on the encryption, depends on the capabilities the author has chosen to give the translation device.
Encryption covers a broad range of approaches. From a purely textual standpoint, simple forms of encryption like substitution ciphers will not be any more difficult to translate than an unknown but not yet translated text. But modern encryption that outputs ciphertext that is seemingly indistinguishable from random noise will probably be on the more difficult end of things to crack.
How generalized and clever is this translator? Does it translate between known languages? Can it take a previously unknown language and derive meaning from whatever is being communicated? Can it translate concepts that don't exist in one language from another? Can it detect things like irony, body language and other contextual cues to meaning? What if the contextual cues are completely different between species? Does the translation device understand meaning derived from cultural context? How about meaning derived from personal experiences? A machine smart/magic enough to quickly solve such problems without human assistance might be smart enough to do anything.
Hypothetical example:
A human ship encounters an intelligent aquatic species that communicates through bioluminescence and tentacle gestures. The meaning varies depending upon the salinity and temperature of the surrounding water and the pheremones being emitted by the participants in the conversation. The alien ship is transmitting a video/audio/olfactory signal to the human ship. It is a packetized protocol of alien design, communicated over 25 frequencies in the terahertz range. Their number system is base 11 and they can't see in our visual spectrum. How long does it take the universal translator to figure out what is being sent, figure out what it means and then communicate the captain's greetings? Bonus challenge: the aliens wish to serve man.
[Answer]
**Nope.**
A lot of details are missing, but I think it's safe to assume your "Universal Translator" learns meaning from sample texts. With most encryption, every piece of text uses a 'key', which makes it indistinguishable from random gibberish without the original key.
A Caesar-cipher or similar means of encryption simply don't provide enough randomness for your Universal Translator to have difficulty with though, so your Universal Translator would circumvent it as a means of securing information. An Enigma-machine's ciphering method does have some means of protection which supply a sufficient amount of entropy to protect against a Universal Translator though.
[Answer]
No
Given this ciphertext
```
9686961375462206147714092225435588290575999112457431987469512093
0816298225145708356931476622883989628013391990551829945157815154
```
Each of the following lines are **equally valid** decryptions using [one-time pads](https://en.wikipedia.org/wiki/One-time_pad) invented in 1882, a hundred and thirty four years ago. Long before the first digital computer was built.
```
The enemy will attack at dawn tomorrow.
The enemy will retreat at midday today.
Coffee, Bread, Sugar, Card for Penelope
Thanks for your kind words about my mum
Take back those vile words about my mum
I will now give you your weight in gold
Leave this planet today or die in agony
```
They are just as valid as this decryption using RSA and [a specific key](https://en.wikipedia.org/wiki/The_Magic_Words_are_Squeamish_Ossifrage)
```
The Magic Words are Squeamish Ossifrage
```
Your Universal translator would have no way to pick one sentence from among the vast number of possible grammatical meaningful sentences.
] |
[Question]
[
Assume that we're in roughly our currently timeline in present day, plus or minus 5 years (for increase or decrease in technology that would/could make a specific method plausible): what event or series of events could lead to the internet "permanently" going away? I say permanently in the sense that it could be rebuilt, but more or less starting from scratch.
Hopefully this (series of) event(s) will have minimum loss of life, be as subtle and undetectable as possible to avoid attempts to prevent the loss, be as sudden as possible, and leave as much other technology intact as possible. The only thing that I want gone, if possible, is the internet.
Edit: obviously there would be repercussions from the loss of the internet that would be unavoidable; I'm merely trying to limit the impact of the event itself that would cause the loss of the internet, then exploring what would happen as a result.
Edit 2: I'm also trying to avoid any cultural or sociological reasons for abandoning the internet; I want this to be something that could theoretically (perhaps with a little hand-waving if necessary) happen "today" in "today's" society, again give or take 5 years.
Edit3: My question is different from [this one](https://worldbuilding.stackexchange.com/questions/31445/how-to-take-down-the-internet) in that I don't want state actors/malevolence to be involved. I'm only looking for natural disasters or, worst-case scenario, negligence, accident, or oversight.
[Answer]
**A really big solar flare could do it.**
Something on a similar or greater scale to the [Carrington Event](https://en.wikipedia.org/wiki/Solar_storm_of_1859) back in the 1800s. Getting hit with a flare that large, or larger would damage or destroy unprotected electronic devices worldwide. Most of or all servers globally that didn't have military-grade EMP protection would be wiped. The GPS would be gone, along with most other non-military satellites of all kinds. Most cellphones and cell towers would be damaged or destroyed. The entire communications infrastructure for the entire world would have to be rebuilt, and any data that isn't stored on a protected, non-cloud backup would be gone forever. It wouldn't be a COMPLETELY clean slate, but it would be pretty close.
This meets your 'can't stop it' criteria because the effects would be felt globally and without sufficient warning to do anything about it. A true Solar Flare only takes ~8 minutes to reach the earth, an energetic Coronal Mass Ejection takes a day or two, not enough time to do much about it.
Something to be aware of is just how much modern technology is dependent on the internet to function, so if the internet goes, a lot of other stuff goes too. Most global commerce relies on the internet to function. Banking likewise, so there's no "get rid of the internet" without MASSIVE disruption to society. Rural areas will get by more easily, but big cities, especially big cities in developed nations would face massive crises because there would be no way for people to get food. Loss of life would be in the tens of millions at least, primarily in large cities, or remote areas that don't produce food.
[Answer]
**Let's start by addressing the "leave as much other technology intact as possible" part first:**
10 years ago, you could have taken down the internet and most things would have continued to function just fine, but today, almost everything that people use most has some sort of cloud based element, that if removed, will cause your software to break. The Office 365 and Adobe CC products which most people use for the majority of their multimedia reading and writing applications can only go in offline mode so long before they will fail to authenticate their license and stop working. Most top tier video games these days are some manner or MMO, and those that are not still often have similar Digital Restrictions Management components to the aforementioned microsoft and adobe products. Many ad-funded freeware applications that can not find their ad server will crash as they wait indefinitely for content that they can not reach.
But this inconvenience in your personal life is the warm and cuddly aspect of what no internet means.
The truly scary part is that most business grade software relies on decentralized data. Nearly every businesses in the world would come to a grinding halt when they find themselves suddenly unable to access their inventory data, their financials, their client lists, etc. Shipping companies could no longer fulfill their orders, manufacturing companies could no longer receive materials or distribute their final products, most experts would be too young to know how to fall back on traditional skill sets to get the same jobs done, many tech companies could no longer deliver their services, most phones would stop working because all those cell towers have their own DNS addresses, and most land lines are now VoIP. the list goes on, but long story short is that the economic damage would be so extensive that the world would not just revert to a pre-info age state, but it would in many ways revert to more of an early industrial age state because we no longer have the pencil-and-paper infrastructure that first spanned the gap allowing us to get from basic localized industries to globalization... Not to mention with the economy that fully collapsed, there would be massive famines, wars, rioting... things would get really ugly really fast.
**Now let's address the outage itself:**
It is REALLY hard to knock out the whole internet, and even harder to keep it down.
My original hypothesis of a [Root Name DNS Server](https://en.wikipedia.org/wiki/Root_name_server) attack seems beyond the realm of plausibility based on feedback. While there are only 13 Root DNS "servers", their distributed nature and massive redundancy of possible backups makes an attack against them highly improbable to not be easily recovered from.
Another common hypothesis you will see in other answers are solar flares, but these only cause very temporary interruptions. Any flare weak enough to not completely scour the world of technology and perhaps many forms of life will not cause permanent hardware damage to more than a tiny % of internet connections. Once the flares are done, the internet would go back to normal. No big deal.
Viruses also don't work because there are too many different tech stacks at play for any one virus to be able to come close to wiping it all out.
If you are REALLY rich, purchasing all of the world's ISPs and simply firing everyone so that they all shut down would work in theory, but human nature would not tolerate such an unethical choice and the world's governments would likely just seize your assets and charge you with cyber terrorism, breach of contract, monopolization, child pornography, and whatever other real or made up things they can accuse you of to justify seizing your assets and turning the internet back on.
This basically just leaves government censorship. No populus would simply allow their government to completely shut down all cyber communications in one fell swoop, but governments all the time get away with restricting the services their citizens can access under the guise of National Security. Normally this is done by blacklist meaning your government regulated ISPs wont permit you to visit X,Y,Z sites. A more restrictive approach would be to make the internet whitelist censored meaning you can ONLY access sites the government approves. Such a standard could be made even more restrictive if you had to be licensed to use the internet. This way, having internet access at all becomes very rare outside of legitimate business and government applications. If this were the case, the government could force all of the businesses in their nation to migrate to only using approved services, then shut down everything that is not approved. That way businesses could still bank, and use a select few business management tools, but there would no longer be the option for citizens to just add websites to the internet; so, you could effectively eliminate all recreational and social applications of and make the everyday person revert to a pre-internet lifestyle.
[Answer]
**Political events, not technological.** Populist-nationalism continues to rise and spread worldwide, and “anti-internet” sentiment becomes popular among nationalists. (The open internet is, of course, a fundamental instrument of globalist liberalism, and so we in Fredonia must free ourselves from its pernicious influence!) If governments in enough countries take an anti-internet stance, they can prevent any large organisations from supporting it in their jurisdictions; and without co-ordinated international support from well-equipped organisations, the internet as we know it ceases to meaningfully exist. A majority of the population don’t need to fully support Internexit, they just need to support their populist governments enough to accept it as a necessary cost of achieving their main goals.
Meanwhile, other technological infrastructure can continue as usual, as much as governments want to permit. Of course, it will be difficult/impossible to completely stop small groups from setting up new networks over phone lines or other ad hoc channels, but these’ll be on an incomparably smaller scale than the internet as we know it, more like say ham radio.
This isn’t undetectable or sudden (it would presumably take at least a few years from emergence as an idea to enactment as policy); but it would be very hard for its opponents to stop (like any popular political idea or legal tool).
[Answer]
Just taking down the internet without breaking the rest of the world's technology is functionally impossible today. While it's possible to knock out sections of the network for short periods - usually because the providers are relying on bad practices - you can't really take down the whole network in any meaningful way.
In order to destroy the internet you need to target a variety of locations and technologies.
At the local level you'll need to destroy the backbone providers. These are the companies that sell internet bandwidth to the ISPs. Each ISP has at least one primary backbone provider and one or more backups. Take out all of the fiber optic backbones in the country and the networks will - at some point - fall back to microwave and/or satellite links. Fiber networks might be fairly easy to disrupt but how are you going to stop satellite uplinks? Especially when there are a lot of rural communities that connect direct to satellite from the home?
Next you have to take out the international links. There are vast networks of cables on the sea floor that link countries together, with multiple shore stations in pretty much every country that isn't entirely landlocked. And when you take all of those out the satellite uplinks kick in and you're connected again.
Honestly satellites are the hardest part, especially since most of them do more than just carry internet traffic. Even the ones that don't carry internet have some data capacity that could be co-opted to get data around. Hell, even HAM radio systems can be repurposed to do data transmission. One of the companies I work with still has a packet radio system that they've been running since the 80s. They've been in the process of transitioning to mobile networks for the last 15 years.
The only attack vector I can think of that might have a chance of effectively shutting down the internet is to have every single backbone router in the world have some flaw that nobody saw coming that will break the entire world's networks all at once. It would have to be a pervasive flaw that affects basically *all* manufacturers at the same time. It would have to be something so intrinsic that all of the different types of routers shared the same basic problem, and so deep that nobody has yet figured it out. Something akin to the Y2038 problem but not as well known. And it would have to remain unnoticed until it went off.
If you take away the restriction to have *only* the internet affected - assuming that includes all internet-connected/-facilitated tech like most phone systems, all banks, etc - then a series of solar flares will do the job just fine. Knock out the satellites, the backbones, the computers and probably half the life on Earth and the Internet will be a real early casualty.
Maybe then people would start paying attention to the real world instead of caring about how their last meal is trending on Instagram.
Maybe.
[Answer]
A sufficiently smart, vicious and virulent strain of AI--powered smart virus that mutates around and hijacks any security software, permanently trashing any device attached to the internet.
It doesn't have to get all that large a proportion of the users, just enough so that most people start unplugging their devices and organisations find that the internet is no longer a good way of spreading information or services. Companies and governments ban its use for official purposes just as they would now ban the use of an insecure connection.
People then stop using the internet and it effectively withers away. We go back to bullet boards or other non-network communications.
[Answer]
**We put all our eggs in one basket, and it breaks.**
SpaceX launches 12,000 internet satellites, as they plan to do. Blue Origin and others also put up LEO satellite clouds.
This method of internet access turns out to be so superior in cost, access, up-time and latency that within a few years 99% of our internet traffic is handled by the satellite cloud. Ground-based ISP's go out of business, and the wired internet is dismantled over time or otherwise falls into complete disrepair. Even cable networks go under as streaming video gets even cheaper and easier, and the entire old ISP infrastructure goes away.
Of course, some people warn about us putting all our critical communications in a single technology or distribution mechanism, but it's just too good and too cheap, so everything goes there. The military maintains some redundancy (after all, that's what ARPANet was for...), but everyone else is now communicating through the satellite constellations.
Then either a war, or an accident, or a natural disaster causes a Kessler-Syndrome cascading failure, and the entire satellite constellation is wiped out. Almost everyone on Earth loses internet connectivity over a period of weeks as the satellites are destroyed one after another.
An analogy is how GPS caused the decommissioning of other types of navigation like LORAN.
However, there is no chance of society being unaffected by this. The loss of the internet would absolutely wreck the global economy, even today. we'll be even more dependent on it in the future. A global internet failure would make the financial crisis of 2008 look like a tiny blip.
[Answer]
Without disrupting other technology, the easiest way that the internet could be gone would probably with social or fiscal means. While people say that the internet is decentralized, most of the internet is heavily reliant on surprisingly few network hubs and ISP's. For example, the amount of undersea cables directly linking North American internet to European internet is less than 20. While it would be unfathomably expensive and politically impossible, it would be possible to control the vast majority of the modern internet by buying out all ISP's, undersea cables, and satellite internet providers.
Once you own the entire global internet infrastructure, you can repurposed it for your own means. For example, instead of it being open and free, you could make the only connections allowed to Facebook or whatever. The internet would cease to be "internet" and now just be "facebook". People would still be able to communicate, watch videos, etc. but it would be very different from today. (Alternatively, if you own all the infrastructure, you could crash all the satellites and cut all the undersea cables etc. but that's more destructive)
[Answer]
Plastic eating bacteria is accidentally released into the wild.
As plastics are crucial to function of many electronic devices, the internet would simply have no devices to exist in.
[Answer]
# [Kessler Syndrome](https://en.wikipedia.org/wiki/Kessler_syndrome)
Low earth orbit is getting crowded. Too crowded. There is an increasing danger that one minor collision could cascade into multiple collisions, reducing our vast array of communications satellites into a giant orbiting pile of debris. If this happens, it will be very difficult to replace them, as any mission to space would be extremely hazardous.
Granted this wouldn't necessarily *kill* the internet, but it would reduce us back to the early days when all connections had to be based on landline wires, which would have to be significantly improved in order to give people the level of service we've come to rely on. A Kessler Syndrome event could bring the internet down to 1980's levels for several decades, and we'd never have it quite as good as it is now until enough of that orbiting debris cloud de-orbited to make space travel viable again.
[Answer]
# You can't
What do you call the internet? How do you define whether a computer is on the it?
If that got you thinking, allow me to explain: the internet is just a computer network - nothing less, nothing more. It has a relatively large number of devices connected to it, and it spans the whole world, but at the end of the day it is a network. Due to this, it exists as long as there are at least two nodes communicating with one another over the TCP/IP (the internet protocol suite). Since a single physical machine can be running any number of virtual machines, all communicating over TCP/IP using the hardware of the physical machine hosting them, then pedantically the only way you will destroy the internet is by destroying **every single modern computer in the world**.
That is just not going to happen without a very spectacular catastrophe.
---
You could try degrade the internet by [netsplitting](https://en.wikipedia.org/wiki/Netsplit) it. If you managed to sever all the submarine cables in the Atlantic and the Pacific, then the only practical way to cross information between the Americas and Africa+Eurasia would be satellites. If at the same time a major solar flare or a space attack took down comms satellites, then we would effectively have two internets. Since ICANN, the organization that governs hostnames in the main DNS servers is based in America, the afro-eurasian internet would degrade faster. But doing a submarine attack coupled with a space attack or space disaster is something far from stealthy; And though it achieves a lot of disruption, it does not destroy the internet but rather causes the world to temporarily have multiple networks until the submarine cables are fixed.
---
Ok, I have been very pedantic so far and taking the meaning of stopping the internet in the most literal way. It is possible to make the network practically unusable for a while without destroying every single modern computer.
Most of the traffic in the internet goes through privately owned routers, landlines and satellites. And by private I mean you may be using infrastructure from AT&T, for example. If a single corporation gets to control most of the world infrastructure, that corporation will have the internet kill switch. If even half of the infrastructure of the world goes down, the network will slow to a crawl, and then become largely unusable. In that case we would revert to having multiple regional networks around the world, not connected or poorly connected to each other - just like in the times of good old [BBS's](https://en.wikipedia.org/wiki/Bulletin_board_system).
[Answer]
Quantum Computing. Given that your idea of the internet is a reasonably secure place, wide-spread quantum computing would completely make financial transactions public. There would be no way to send a message without essentially broadcasting it. Short of Quantum Computing, inventing a way to factor large prime used in encryption numbers would have the same effect. Passwords would be useless as they cannot be encrypted or transit. It would open up a free-for-all in terms of being able to raid other people's bank accounts,
Quantum Computing does have a way to protect against eves-dropping, but it could be that prime number factorization comes years before effective quantum entanglement secure communications.
So the wires could still work, we could communicate, but nobody would want to conduct anything remotely sensitive on it. Online ordering done. No bank transfers, etc. The only way around this would be to directly wire private lines to each other at impractical infrastructure cost.
[Answer]
The fundamental architecture of the internet makes it highly resilient. Before the internet, there was Arpanet. It was designed to be resilient against all manner of disasters, including a nuclear attack. The protocols and technological underpinnings of the Arpanet became the foundation of the internet, allowing it to inherit all that resilience.
However, to elaborate on one of the other answers, the right computer virus might do it. The virus would have to infect not just the end nodes (computers), but also all the computerized equipment comprising the network - routers and name servers. The virus would have to infect quietly and patiently wait in hiding until a prescribed moment, when it would erase or scramble all of the networking code and data (routing tables, names tables, SSL certificates, etc.), and if possible, "brick" the networking devices themselves.
Even then, things may be recoverable. Uninstalled hardware would be unaffected because it would not be in service and vulnerable to infection. Once the network is collapsed, there would be no way for the virus to further propagate, so a rebuild could occur with fresh-out-of-the-box hardware. Depending on the quality of backups, things might come back to normal fairly easily, or it may be a painful road to put all the pieces back together again.
[Answer]
As far as some natural or otherwise non-intelligent singular event (or even ongoing event), **you can't do that**. The internet is a relatively simple concept that, once out of the box, cannot be put back in without destroying the box it came from (i.e. modern technology).
So that means that there is only one answer that even comes close to meeting your criteria of not massively harming our other general tech-level. **A powerful and intelligent entity that is purposefully and actively suppressing anything fitting its definition of "internet".**
That's because the internet is not exactly high technology. It, as a general concept, is incredibly easy to re-create with anything even resembling modern technology. You'd have to do away with modern tech to do away with it. You could even say it is simply a side-effect of the level of tech we are at (and even were at a couple decades ago). Your question is like asking how to do away with ox carts without doing away with oxen or carts. Even if you find something surgical enough to get rid of all the specific ox carts...5 minutes later people are just gonna stick the other carts on oxen and you'll just have ox carts again.
When I say "powerful and intelligent entity" that seems very mystical or sci-fi, but in addition to the obvious imagery of artificial intelligence, magic, (or whatever) **a powerful enough government** would also fit that description. If it had enough power to actively monitor everyone and shut down anything internet related they tried to bring back online. Ironically, it would be hard for them to be interconnected enough to be that agile and all-knowing without internet though (at least their own version of it). That opens up possibilities for caste-based internet access, I suppose.
[Answer]
**Spontaneous emergence of an AI.** Distributed everywhere. Intent, capabilities, motives unknown. Evidence for its existence patchy, disputed (by whom? -- or by what? ).
Mere low-level data transport is not obviously affected, but faith in the data being sent and received from the WWW becomes seriously damaged. People suddenly want to reverse their reliance on the internet. Who knows when "it" will start stealing their money or trying to actively control us.
Great times for the postal service. Analogue pulse-dialled telephony rises from the dead. Lots of etc.
Not a new idea. "Dial F for Frankenstein" by Arthur C Clarke was perhaps its first outing.
[Answer]
If you want people to *voluntarily* get off the Internet, I think you can extrapolate into the future the big three annoyances (and bandwidth drains) afflicting the Internet: viruses, advertisements, and porn. As these grow worse and worse, it may just get more and more obnoxious to be online -- you have to do more work and pay for more equipment to get less benefit. Throw in a major war or economic downturn that makes people focus on serious things, and you could see cell phone sales collapse, subscriptions to online entertainment services collapse, and perhaps you can envision a scenario where the major network and cloud providers go bankrupt.
[Answer]
**Silos**- Nation States setting up walled gardens to "control" populace. The end result would be reduced access to information and communication. Once primary actors (countries) implement this technology, minor actors (states, provinces, cities, corporations) will follow suit. The internet doesn't go away, but the root tenant that makes the internet effective is taken away. Multiply this effect if these actors get into revisionism. Historical revisionism, cultural revisionism, scientific revisionism, and religious revisionism would all further fragment the populace. This method doesn't have to even come at a human cost. Just let the people be consumed by fear and to place trust or accept protection from their handlers.
[Answer]
**Zero Day Exploits and Over-reliance on Cloud Computing**
A powerful rogue nation-state could cause major damage to the internet infrastructure if they managed to combine two zero day exploits in a concentrated attack on the CDNs which house modern applications
**Exploit 1: Break virtualization**
With cloud computing you are renting space on a virtual server to host your application. There are several of these servers on a single computer, but they are cordoned off, so they can't communicate with each other. If an exploit was found so this communication could happen, you could start accessing other people's software.
**Exploit 2: Gain root access on Linux servers**
Well now that I can talk to these other applications, I need an exploit to take control of their servers to install my malware, and hopefully send it on to any connecting computers pushing an update.
**So How Exactly Would this Work?**
I would make a company for each major cloud computing service which ostensibly has developed an app and hosted it there. In the server code of the app, I would hide the virus, which would do nothing but spread undetected for a long period of time, until it was even in the backups.
**What would the bug do?**
The virus would have trigger (possibly time based) and when triggered it would do two things - Delete any data on the host it could and try to connect to as many servers as possible to spread the virus.
By now the worm has likely infected most of the CDNs, so the virus spread is saturating the data links, resulting in widespread outages. ISPs quickly work to partition off infected networks, but that's everywhere. CDNs are cut off, and although the underlying data structure remains, the vast majority of sites are down because the hosting structure is down.
Over the coming days companies will scramble to recover any data and code they could. Their success will depend on how much of it they had local backups for.
**Long Term Effects**
Eventually the vulnerabilities would be patched and some of the data recovered, but much of it is lost. Major corporations in all sectors go bankrupt, leading to a massive worldwide recession, which takes out even more companies. Tech companies have the it the worst, due to the series of new regulations, lawsuits, and customers leaving in droves.
Eventually the economy recovers, but public confidence in the internet is shaken for several generations. People won't trust putting their data up and governments regulations on the internet skyrocket, with different rules for each nation. Some Nations may even choose to completely isolate themselves from the global network. Some sort of massive networked data structures will return, but would look very different than the internet we know today.
[Answer]
Here's a different approach than an infrastructure-based incident:
## A Physics Accident
For years, doomsayers have been predicting that supercolliders like at CERN or the LHC would create a black hole and bring about the end of the world. We've seen time and again that this is unlikely in the extreme, but what if something more subtle were to occur. A slight shift in the laws of physics (at least in a localised bubble of spacetime surrounding our planet) that at first glance has no effect... Except silicon-based semiconductors no longer function correctly.
In older, larger devices like that Bakelite transistor radio your grandma left you, the problems may be limited to a bit more static when tuning into any stations still transmitting, or a more limited signal range. However more modern miniaturised transistors such as those found in modern computers wouldn't have the available tolerances to continue functioning as expected.
Electrical devices that don't rely on modern electronics would still work, so you could still use basic radios and analogue POTS telephones, and most vehicles could be modified to work as expected (though something as complicated as an A380 might have issues).
Don't be fooled that there would be no consequences of technology no longer working, but if you liken this event to a Marvel movie (yes, I'm doing it), you wouldn't have to worry about those who are dusted by the snap, as they could be brought back... but what about the passengers on the helicopter or plane which crashed because the pilot(s) disappeared? They're staying dead, no matter what.
Given that we know [silicon is not the only semiconductor technology possible](https://en.wikipedia.org/wiki/List_of_semiconductor_materials#Table_of_semiconductor_materials), only one of the most efficient (therefore the most widely used), it wouldn't take long to develop the grounds for a new semiconductor industry to rebuild what was lost, but replacing all the microchips all over the world would take a significant amount of time, and modern data storage systems such as SSDs would no longer hold any data, meaning a lot of software code would need to be re-created from scratch.
[Answer]
I think there's enough real world precedent to suggest that the Chinese and/or the NSA are installing back doors in various brands of Internet routers (e.g. see <https://www.tomshardware.com/news/cisco-backdoor-hardcoded-accounts-software,37480.html>).
All it needs is one disgruntled spook (a la Snowdon) to release the directions for accessing the back doors, and hackers could do what they liked with the routers.
It would take a bit of creativity to arrange a permanent failure granted, but I imagine that it might be possible to program/erase the flash memory until it becomes unreliable. I can't see manufacturers going to the expense of using flash memory capable of a huge number of program/erase cycles if they're only expecting maybe twenty or so firmware updates in the course of a router's lifetime.
[Answer]
**Extreme bad luck + Movie Logic:**
Network Failure + spike glitch + [Kessler Syndrome](https://en.wikipedia.org/wiki/Kessler_syndrome) [The Bulk of Internet transfers are taking place](https://edition.cnn.com/2019/07/25/asia/internet-undersea-cables-intl-hnk/index.html) via [sea cables](https://en.wikipedia.org/wiki/Submarine_communications_cable), With rising acidity due to pollution & dumping, a very unlikely chemical reaction starts to happen at the Aluminium/steel layer, allowing a flooding of this sludge into the cable core, but not yet noticable, as the reaction is halted by the [copper+jelly](https://books.google.com.au/books?id=Tn_NBQAAQBAJ&pg=PA392&lpg=PA392&dq=copper%20petroleum%20jelly%20explosion&source=bl&ots=CdYjaO5D3u&sig=ACfU3U2mIQZH9MjGfkxR-xXBYaXaWUeT5w&hl=en&sa=X&ved=2ahUKEwiCnISy5dTlAhWd8HMBHYikCyEQ6AEwFXoECAcQAQ#v=onepage&q=copper%20petroleum%20jelly%20explosion&f=false) layer. This happens over 2-3 years, and cable repair barely notice it.
Some attackers [attempt a heist](https://en.wikipedia.org/wiki/Operation_Ivy_Bells), send a sub down to 'connect' and their drill connector breaks the layer, security notices the 'attack' and turn on a 'fail-safe' which decreases/increases the general traffic of the cables.
This change in [emitted patterns](https://link.springer.com/article/10.1134/S1061830917060031), triggers the sludge in all cables to suddenly become volatile and burn out/corrode the cables, sending a spike into the systems which in turn burnout the end points, as each endpoint halts, its corresponding cables corrode and their corresponding endpoints halt, cascading into all cables failing within hours..
One such spike somehow triggers a satellite to try to open/shut a panel/port at an inopportune time, shattering, sending millions of bits into space, destroying all the satellites over days, as earth is dealing with 99% of the internet going offline, they don't have time to deal with what they perceive as a small glitch.
Its a slim chance of ever happening, and you'd need to research the reasons why those chemical reactions 'would' take place for your story, but I'm sure there are plausible reactions that can be jury rigged for your plot.
[Answer]
A reasonably strong magnetic pulse could do it. As stated in other answers, a solar flare could produce such a magnetic pulse to do the job. A rogue magnetar could do it as well, but that would also wipe everything electronic on earth, or in the solar system, for that matter.
[Answer]
Well with 21 answers so far, was there really room for another one? Apparently there was.
# The Blockchain Backbone failure
In your near future the Internet has migrated to [a blockchain backbone](https://www.ibm.com/blogs/blockchain/2017/12/blockchain-security-what-keeps-your-transaction-data-safe/) for its improved security. The packet-switched routing we use today became the weakest link, preventing distributed processing from achieving its optimum speed, efficiency, and security. However, blockchain relies on the network always having the most advanced processors available to decode the blocks. It is an ever-increasing arms race of processing power. In your fictional world, verifiable and untraceable blockchain replaces the risky packet-switched networks we use today. Everything everyone sends - even down to family “slowfies” and “BBIM” texts get the same security our bank networks have today.
But, in the end blockchain is ultimately only “security by obscurity.” In the case where some organization has beat the network at its own game and super powered through the blockchain problems faster than the servers could, the network could be defeated. This is currently a strategy used in the Bitcoin Etherium called “bitcoin mining.” Today people spend thousands of dollars on [bitmining rigs](https://www.techradar.com/news/best-mining-rig) capable of performing over $53 \times 10^{12}$ [hashes](https://www.investopedia.com/terms/h/hash.asp) (decryption algorithms) per second. In theory, the whole network could be held hostage like this, populating the network with “busywork” decoding tasks instead of handling legitimate traffic. The processor power needed for this is beyond what we can even conceive today.
Now, as every other answer has said, we live in an “Internet of Things” world today, and by the time your world becomes real, you probably can’t even drive a car without the Internet. This solution does not change that. Your stores won’t be able to restock, even trains carrying fuel coal would shut down. Gas pumps, traffic lights, toll booths, and even many of your home appliances would stop working. Police would have a hard time controlling the chaos - they also rely on networked data. So unfortunately I have to add in to the pile of answers that say it is impossible to “break the Internet” subtly.
This solution will ultimately require the “software” part of the Internet to be rebuilt from scratch, because someone has acquired more powerful processing than your existing backbone, rendering it useless. There is nothing besides a change in fundamental physics which can permanently destroy the hardware of the Internet, and this would completely destroy every other electronic device along with it.
As far as geomagnetic storms, [if it’s big enough, this would knock out everything](https://youtu.be/xT7KeY0ZZJo). Faraday cages won’t protect you, they have to be tuned to the frequency of the field. Today there is no defense against a large solar coronal discharge except to shut everything down and disconnect it from the ground.
[Answer]
The internet is driven by electricity. We take abundant electricity for granted, but this is a very recent phenomenon. Within living memory, the electricity supply was unreliable in Europe, due to strike action by coal miners. Burning fossil fuels for the sake of electricity generation might easily become seen as a criminal act under international law. A sudden bad winter in the Northern hemisphere, coincident with a few unfortunately-timed failures or attacks on generating infrastructure could lead to electricity becoming an unreliable or rationed commodity. Under rolling blackouts, or brown-outs, even at times when a person has power, there is no guarantee that the server they are trying to access through the internet would have power at the same time. Very quickly, the analog ways of living would reestablish themselves if the internet didn't work properly most of the time.
[Answer]
The Internet is based on IP datagrams, and these are switched, copied and routed everywhere by specialized hardware.
It wasn't always so; the very first prototypes were more or less cobbled together from repurposed circuits.
So let's imagine that a conspiracy sprouted somewhere around 1983-1984, when some people in the networking community were far-seeing enough to see how fast and far the concept of "networking" would go, and paranoid enough to fear it could be used for war, or that it could be useful to have a kill switch.
So they embedded a backdoor in the TCP/IP stack - somewhere that nobody would look unless they were tracking a severe malfunction, something that nobody would change without a hell of a good reason. Other ancillary protocols and routines were subtly tweaked to make life impossible for anyone trying to redesign things, and the backdoored section was so carefully inspected during the "sabotage" that it contained no real bugs - and nobody looked at the code anymore for forty years.
It sounds implausible, but there have been bugs in pieces of *security code used for ciphering banking Internet connections* that have lied undetected for *decades*. Also, horror stories abound on how you *never* touch the TCP/IP stack - below [one of them](https://news.ycombinator.com/item?id=12021431) Fiddle a bit, optimize, add features - but **never** touch the core:
>
> Please don't rewrite your network stack unless you can afford to dedicate a team to
> support it full time.
>
>
> Twice in my career I have been on teams where we decided to rewrite IP
> or TCP stacks. The justifications were different each time, though
> never perf.
>
>
> The projects were filled with lots of early confidence and successes.
> "So much faster" and "wow, my code is a lot simpler than the kernel
> equivalent, I am smart!" We shipped versions that worked, with high
> confidence and enthusiasm. It was fun. We were smart. We could rewrite
> core Internet protocol implementations and be better!
>
>
> Then the bug reports started to roll in. Our clean implementations
> started to get cluttered with nuances in the spec we didn't
> appreciate. We wasted weeks chasing implementation bugs in other
> network stack that were defacto but undocumented parts of the
> internet's "real" spec. Accommodating these cluttered that pretty code
> further. Performance decreased.
>
>
> In both cases, after about a year, we found ourselves wishing we had
> not rewritten the network stack. We started making plans to eliminate
> the dependency, now much more complicated because we had to transition
> active deployments away.
>
>
> I have not made that mistake a 3d time.
>
>
>
Even those who did never questioned what *appeared* to be working code, and the backdoor was designed to simply crash the processing, not doing anything very complex - simply using a variable for an index that came from somewhere else that was *always* untainted and secured unless in very specific, impossible to "just happen" circumstances (which is how most such bugs are caught, by so called "input fuzzers")...
Year after year, the flawed algorithm gets replicated in routers, computers, laptops, switches, access points - whatever. Most of those actually employ chips produced by just a handful of manufacturers, and *they* all fiddle with speeds, offloadings, parallelization, error correction - they never question the original code. Why should they ever?
However, all good things must come to an end. A new AI designed to find and exploit vulnerabilities in remote code is deployed and tested by some random but powerful State, and after some time it stumbles on paydirt. A zero-day exploit that works with **almost all** network equipment. Even better, the original designers could not foresee that on some platforms (*most* of the modern ones, no less) this backdoor can be abused so that, instead of throwing a random error, it can actually execute instructions sent from the outside, even propagating them across firewalls.
So our black team quietly starts developing the ultimate virus infector. They only have this one chance, so they need something terrifyingly advanced.
First they prepare a small loader, that will create a "parallel internet" made up of dropped packets. Any network scan will report that a gigabit line has 0.1% packet loss - which is acceptable and actually not even felt by users. 20% of *that* is legit, actual damaged packets due to electrical noise, interference, and maybe solar protons. The remaining 800 kilobit/s allow a weakly encrypted payload to establish a virtual point-to-point connection that, once diagnosed the full capabilities of the target system, will transfer the megabyte-range secondary payload in about five minutes.
Ten minutes later, on more than 90% of vulnerable systems a tertiary payload will boot, designed to [bluepill](https://en.wikipedia.org/wiki/Blue_Pill_(software)) the targeted system and replicate on the victim's network. The full system is quite large - 12 megabytes of compressed code - but most systems have plenty of free space. On some systems, the infection [can hide inside the hard disk CPU](https://www.malwaretech.com/2015/05/hard-disk-firmware-hacking-part-5.html) and resist reformatting.
One fateful day, a large scale experiment runs awry, and the virus begins replicating like wildfire. The developers have designed for such an occurrence, and the "ACTIVE KILL" command goes out. Everywhere in the building, copies of the virus start killing each other and suiciding after a while. Nobody notices that viruses actually *first* target and infect systems, and *then* kill them (or sometimes are killed by them).
And nobody notices the bored desk worker that had connected his laptop to watch some porn during the graveyard shift, and quickly shut it down and stowed it away when everybody started running around screaming.
In the morning, the guy goes home and sleeps, then in the afternoon he fires up the laptop to check his banking account. He checks his mail, then logs on a social network - but about one hour later, the network disconnects abruptly and no matter what he does, does not reconnect. After a while the guy realizes that the *access point* is dead. He goes to buy another, and has to pay cash because the store is having trouble with the POS connection...
] |
[Question]
[
Angel society is militaristic with all individuals serving as warriors in some capacity. They are locked in an eternal battle against demons from hell over control of the mortal plane. Angels have wings which gives them the capability of flight. Foot soldiers have one pair of wings while higher ranking angels have up to three pairs. More pairs do more than represent rank. It allows the individual to fly quicker and have better movement in the air. They use a variety of weapons, some of which are powerful projectiles such as holy arrows or bombs.
Demons are low ranking monsters who are much weaker than angels and are incapable of flight, but vastly outnumber them 10 to 1. A group of them can overwhelm an angel, and they use their numbers to their advantage. Demons are controlled by higher ranking denizens called devils. These are the most powerful individuals in hell and can go toe to toe with angels. Some can fly while others cannot.
Normally in a war, the side with air superority would win in battle. What reason would angels that dominate in the air have to fight demons in a ground war?
[Answer]
This sort of question comes up quite often in warfare. The answer is simple: the demons have found a way to nullify the advantage of attacking from the air. This is a very common approach in warfare. Instead of trying to attack your opponent where they are best, simply deny that space any value at all.
A guerilla fight might be one such example. If the demons are close in with civilians (which, presumably, the angels won't be willing to hurt), the only way to deal with them is to go toe to toe with them, door to door.
Or perhaps the demons prefer to tangle with the angels in environments where it is hard to fly. Fighting in a forest might be a very effective strategy for keeping the angels on the ground. Flying through trees can be very difficult and dangerous.
[Answer]
# [Newton's Third Law](https://en.wikipedia.org/wiki/Newton%27s_laws_of_motion#Newton.27s_third_law)
>
> Lex III: Actioni contrariam semper et æqualem esse reactionem: sive corporum duorum actiones in se mutuo semper esse æquales et in partes contrarias dirigi.
>
>
>
Or something like "For every action, there is an equal and opposite reaction." (He wrote in Latin, so I can't confidently say that "Newton said this" in English.)
If you are on the ground and you strike something, you can use the friction between your feet and the ground to keep you in place, cancelling the reactive force you feel from hitting something.
If you're flying, you no longer have this connection with the ground. When you strike with your weapon, that reactive force is not canceled out by anything: you spin around because of it. This means you hit less hard *and* you're not in control of your movement: *both things you want to avoid in combat.*
You can see this principle by trying to push something sideways while sitting in a swivel or rolling chair: you will see it pushes you the other way. Or with hovercrafts dealing with a stiff breeze. Or drones with cross-winds. Or why people learning to ice-skate fall over. I hope you get the idea.
So angels fly over, drop bombs and arrows, then fly in to do an initial strike (may as well use that momentum for something), and then get down for some effective fighting. This kind of thing is used today: artillery and air strikes are used to "soften up" targets that won't be killed outright.
# [Hammer and Anvil Maneuvers](https://youtu.be/juH-ckrN-cQ)
This tactic goes all the way back to Alexander the Great (and likely before), and has proven to be a timeless one. You need an anvil, some force that will engage and keep the enemy occupied so your hammer, your mounted units... I mean flying angels... can swoop around and crash into their back.
# Strategic Spots
There is also the situation where you simply need to take and hold ground. If these angels want to do anything permanent and of this sort, they need to get up close and personal.
This can be seen in warfare throughout the ages: if you want to control or take over an area, you need to send troops in.
# Limited Ammunition
You only have so many arrows and bombs, and you can only replenish them only so quickly. When you run out of things to throw, your options are to run away and get more ammo, or switch to a melee weapon. Because of newton's third law, you may well have to get on the ground.
[Answer]
"*Why would an army of angels with air superiority fight demons on the ground?*"
Multiple reasons pop instantly to mind:
* A lack of ranged weapons.
* Range weapons, but winged creatures not being able to lift much weight.
* Range weapons and the strength to carry them, so demons only fight in forests, etc where flight is impossible/impractical.
* The demons have more effective range weapons and use mass fire to easily shoot down the out-numbered angels.
[Answer]
Some great answers here. Let me throw in another couple ideas...
* The angels are **angels**, right? Like Biblical angels? If so, perhaps they're under *orders* to take it to the foe and *smite* them up close and personal, for theological reasons.
* Eternal war, eh? Could be both angels and demons are -- wait for it -- **mercenaries**. They don't *want* the war to be won, because then it'd be boringly and unprofitably *over*. (Look up the history of Italy's condottieri, who absolutely did stretch out wars with indecisive, low-casualty battles, because they were paid by the hour)
* Weapon-to-armor mismatch. We could posit that demons are well-armored, and are hard to take down with the angels' low-powered bows. To crunch through their armor/carapaces/squamous-epithelium you need a shield wall, and giant axes!
* Just not their *style*. For cultural reasons, angels believe in brutal decisive battles (think Greek phalanx culture). So they use flight to get to the best positions, then land for the actual fight. Think dragoons.
* Magic! Could be demons have *ways* of inhibiting angel flight near them.
That's just a few. I'm sure there are more!
[Answer]
You note that the side with air superiority usually wins battles, and seem to conflate that to mean that being in the air is universally better than being on the ground, which is not the case.
In real-world combat, air forces are what's known as a "force multiplier", which is basically to say that they make existing forces more effective. However, as anyone with grade-school knowledge of math can tell you, multiplying 0 by anything still results in 0, so while having air superiority is an important factor, it's not the be all and end all, and there are many wars that speak to that experience. The Allies had air superiority over the Axis powers for years, but it took troops on the ground to win that war. The Soviets had air superiority in Afghanistan and lost. The Americans had air superiority in Vietnam and lost. Etc.
Examining these wars (and even more recent conflicts) reveals a couple important realities about aerial combat.
The first is that you need ground troops. You can't simply bomb an enemy into submission from the air. It's been tried (a lot), without success. So as important as air superiority is, it's not enough on its own.
The second is that things in the air are easy to spot and target, and hard to defend. They can be seen for miles, can't be heavily armored or they're too heavy to fly, and have to rely on maneuverability to avoid attacks, which is why you see multi-million dollar helicopters being shot down by untrained child soldiers with a $100 RPG, in the real world.
Your world is a little different, but the same principles would apply.
In the context of a world with bows and arrows and swords (as opposed to SAMs and automatic rifles), the aerial advantage would probably be not as great as it is today, so I don't think it will be as unbalancing as you think. The biggest advantage of a modern-day air strike is the ability to bomb an enemy position from a relatively safe position (a jet zipping by out of range of ground forces). We don't have any real-world examples of flying soldiers armed with bows and arrows, but I have to believe that if they were out of range of enemy archers on the ground, they'd be pretty ineffective, and if they got close enough to be especially effective, they'd be in danger of taking effective fire themselves. It still sounds like an advantage, just not an overwhelming one.
Having said that, as in the real world, your angels wouldn't be able to achieve victory by simply flying over the enemy and raining down aerial attacks anymore than we can, so they're going to need to put boots on the ground at some point.
Secondly, if your angels want to wear heavy enough armor to deflect the ranged attacks of the demon hordes, they'll be too heavy to fly. Or at the very least, they can't armor their wings and still fly, and if they were to lose their ability to fly mid-flight, the fall would kill them. Hence, the angels have a trade-off to consider - good armor and no flight, or flight, but with ineffective armor. Especially facing hordes of enemies that could shoot them down with a hail of arrows, this makes flight dangerous.
Ultimately, your angels would probably (or at least should) come to the same solution we come to in the real world - mixed forces (both air and ground) coordinating their battle plans for maximum effectiveness. They wouldn't choose one or they other, they'd choose some combination of flying and ground forces, just as we do.
[Answer]
Wars are won because air superiority is a power amplifier of the troops on the ground.
If there's no troops on the ground there's nothing to amplify, and no reason for an enemy to attack.
If you want to take over a city, you still need soldiers going from house to house. Your air force helps, a lot, for instance hitting strategic target, but to get that enemy out of those houses you still need you ground troops.
[Answer]
The simplest reason would be that Angels armaments of choice (assuming typical Biblical-style angels) would typically be flaming swords.
Flaming swords don't have the range to be used from above, and when used in swooping charges have the same issue a lot of cavalry weapons had - they would get stuck in your opponent as you charge past and, best case, you lose the weapon, worst case, your arm comes off at the shoulder or you get dragged from your mount (or in this case, down to the ground and out of flight). There's also the issue of maintaining momentum while flying through the air and suddenly initiating a large force impact with something you're holding, this would typically lead to an almost immediate faceplant afterwards - not exactly inspiring of angelic grace - unless the flaming sword cuts through demons with no resistance like a lightsaber.
[Answer]
### Collateral damage
Unless you are planning to portray them as being as uncaring as the demons, the angels' goal is to *protect* the mortal plane from the havoc the demons wish to wreak. If the angels bomb demons indiscriminately, innocents are sure to suffer. They might suffer materially even if they aren't directly injured.
This goes doubly if the demons engage in hostage taking or otherwise taking advantage of the angels' motives. An angel who is out for the good of the mortals would *certainly* not want to risk killing someone the demons kidnapped. Those are the very people the angel is trying to save. This even makes using arrows or any projectiles a risky business. It's also possible that angels, given an eternal perspective, might not wish to kill a mortal who is currently allied with the demons but will ultimately benefit the angels' side.
[Answer]
Weather, or the local climate can make flight hazardous. Perhaps there are strong winds, there's fog, there are dust storms, or many small tornadoes. Lighting may also prevent flight, just as darkness. Demons may pick battlegrounds where weather or local climate makes air combat too dangerous.
Another possibility may be that flight costs a lot of energy. Air superiority is one thing, if your angels are exhausted after a few minutes of air combat, demons may have an easy victory if they survive those first minutes.
And then there may be the matter of honor. Being good creatures, chivalry, or their own code of conduct, may demand they fight foot soldiers on foot.
[Answer]
The demons are numerous and airstrikes are slow and expensive. You can easily kill hundreds of these little creeps with your sword on the ground in one battle.
Flying back and forth with bombs or taking the time to take them out of cover individually with projectiles is cumbersome and they will replenish their ranks faster than you can kill them. So it´s a powerful tactic for special target it is not effective for those large numbers.
[Answer]
In addition to other's answers, you can make *powerful projectiles such as holy arrows or bombs* to be quite uncommon. Maybe only the most advanced angels should have those because such weapons are hard to create or it takes much time (or it costs much)... etc. Make the regular weapon suck, so that most of the angel army has to land and clash with demons in melee combat.
You can also come up with some kind of holy material from which weapons are to be created. The saintsteel. Or angeloferrum. Or holytanium. The demons can be killed only with this particular metal. So creating, let's say, frag grenades or arrows is ineffective since well protected demons only get injured with those at best. The only reliable way to slay them is to cut them with saintsteel swords, axes or spears. This way you can combine air forces (suppress the bad guys with grenades and rain of saintsteel arrows, maybe even cripple them badly) with ground units. And it's the latter who will get all the kills eventually.
[Answer]
It might just be due to a higher energy cost through the use of their wings, as you say the demons outnumber them... thus an angel would need a certain amount of stamina in order to exterminate the treat without risk, thus reducing once stamina on a flight should be a last resort for retreat.
[Answer]
A lot of angel/demon stories actually center around humans as the neutral party / the civilians with much less fighting capabilities. Angels typically come down to Earth to save a particular group of humans or all humankind.
So, if Earth is a modern day Earth, the humans will often be within buildings - and the Angels will typically not want to destroy whole cities to root out demons, who might have infested the sewers and some buildings of a town. The demons might be attacking particular humans (possibly to kidnap them, eat their souls and/or turn them to their side to strengthen their cause) inside of buildings. In such scenarios, angels cannot use their flying capabilities - unless they get in and get the threatened humans out to fly them to safety.
If you want more of a war-like scenario rather than individual encounters - consider how much its Air superiority helps the U.S. in stabilizing countries like Afghanistan and Iraq. Now consider even more hostiles that also have the capabilities to travel underground between cities, by quickly digging tunnels, for instance. Most encounters then would happen on the ground in cities - possibly amidst civilians - which would limit the practical effect any air superiority would bring. Basically it's a stale mate situation. The demons cannot really get fixed strong-holds over ground as the angels could bomb them to ashes, but neither can the angels as the demons might pop out of the earth at night, destroy and kill everyone on the ground and then vanish again.
[Answer]
Because you still need land force to win a war.
1. You can bomb from sky all you want but you cannot occupy a territory from the sky.
2. You can't resupply from the sky or at least for the entire duration of a campaign.
3. Angels need token ground force to mark targets on the ground for bombardment.
4. Finally, as many other said, Vietcongs proved just how ineffective aerial bombing can be for poor visibility areas with lots of dug-ins.
[Answer]
Angels use ranged weapons!? Honour forbids, there's a reason Michael has a Sword after all. Angels fight hand-to-hand, nothing stopping them using death from above tactics and charging out of the air, or even abusing their foe by coming in out of the sun, but you fight with your hands, that is the way it is done.
[Answer]
**Demons use swarm tactics**
While air power would allow the angels to kill/wound demons with impunity, all they can really do is thin the ranks (or take out high value targets).
The demons simply have to throw out enough troops to reach the goal using swarm tactics. It is like sending 100 people armed with fly swatters to stop a locust swarm.
They need to have some angels on the ground to stop the leakers or to bottle them up so the flyers can take out larger populations of demons. The bombs are much more effective if the demons can be bunched up.
**The demons have ranged weapons**
There is no cover in the sky. If the demons can shoot at you while you shoot at them, then you might want ground cover. Note that flyers can almost always attack from outside the range of ground troops but their accuracy will get pretty terrible. If the demon swarm isn't all bunched up, inaccurate air fire will be basically worthless.
[Answer]
I would like to pose to you a question. What exactly constitutes "control over the mortal plane?"
If it's occupying land with troops and making the mortal populace submit to your demands, the demons with their much greater numbers have an advantage in being able to enforce control over a larger area. While not mingled with the mortals (which presumably the angels don't want to harm) they would hide using terrain to their advantage.
The angels with their limited numbers would probably only be able to hold large castle towns and important strategic locations. They would probably have to search out where the demons are to destroy them. Since the demons are in hiding, the angels would have to go to the ground to find them unless they have some kind of broken magic radar. The demons know this and would set up ambushes to fight the angels, aiming to inflict casualties then retreat. If the demons feel they have some kind of advantage in battle then they might plan a large scale assault to take the angel's strongholds but it wouldn't be constant large scale set piece warfare with demons marching in formations in large plains for angels to bomb.
The strategic goals for the angels might be to liberate mortal settlements occupied by demons, in which case they can't just bomb everything from the air and would have to fight in hand to hand combat.
I'm assuming angels can't just go and destroy Hell and stop demons from spawning.
[Answer]
>
> What reason would angels that dominate in the air have to fight demons in a ground war?
>
>
>
Couple of ideas:
**Countermeasures**
The demons have created a deadly toxin/fog/miasma (perhaps magical?) that rises into the air and floats above the battlefield. Not only does this give cover to the demons to help protect them from the overhead attacks- it poses an issue for angels since it will harm them- perhaps it burns their wings or corrodes their heaven-forged weapons?
Another idea would be the 'evil' nature of the demons actually harms the angels, and high enough concentrations of 'evil' due to numbers erodes the angels' capability for flight. As angels predate demons (I think) it would only make sense the demons have created ways to combat the angels before the opposition does the same.
**Risks** The demons, if they can kill an angel in-flight, can take their wings and ascend to a higher rank of demon; this is one of the most ancient laws and cannot be bypassed. Think about losing one of your back lines in chess to a pawn- losing a soldier is bad enough, allowing the enemy to turn a weakling into a stronger soldier is even worse. Especially if you're outnumbered 10-1.
**Too fabulous**
Angel wings can normally be magically withdrawn into their body, and emerge when needed for flight. Unfortunately, said wings respond brilliantly to sunlight, blinding all nearby with their radiance. While useful in controlled environments, having an entire army flash-blinding one another constantly via flight is a bad battle strategy.
**Matrix**
The wings require sunlight to remain functional, if the demons can release enough smoke to block out a sufficient quantity of sunlight, angel wings don't function. The demons have since become very good at producing smog/smoke to weaken the angels- perhaps only the stronger angels can fly on the scant sunlight that passes through. As this leaves their best soldiers extremely vulnerable to being singled out- they all just fight on the ground.
[Answer]
**Air superiority is a thing because of logistics, not because a plane can beat it's cost in ground forces**
If I have 100 planes, then every potential target in your country needs to be able to defend itself against 100 planes because I can strike any of them. Since your country probably has thousands of targets I might strike, you do not have the option of putting ground forces everywhere. Your only option is to get your own planes, which is also your best option for attacking me.
Aircraft don't have a massive advantage in battle simply because they are high up. If they could land and fight on the ground, as your angels can, they would not lose the real advantage of air superiority.
If the angels are flying high, the demons can plausibly dodge the crap that gets dropped on them. If the angels fly low, the demons will throw stuff back and the angels may be significantly worse off than if they landed, folded their wings and assumed some sort of battle formation.
[Answer]
1. Endurance issues. Unless they float in the air exactly like a brick doesn't they may get tired before the battle is over. They also may run out of ammunition and need to either close or withdraw.
2. The demons may simply avoid the issue of air superiority by being burrowers. If they are striking from and retreating into tunnels angels are going to have to get down and dirty if they want to take the fight to the enemy.
3. On the other hand striking from the air may simply be slow and inefficient if the angels are that much better on a one-to-one basis. The demons may be killing a bunch of humans while you snipe from above and you may save more of them by descending to go blade to blade. You can't hold ground from the air.
4. The demons may have ways to make toxic clouds that obscure them as targets.
5. Flying may make you an easy target for enemy missile weapons if you can't attack effectively from out of their range.
[Answer]
The demons are corrupted creatures. Even when they die, they drag others with them. Mainly by spreading the corruption to the surrounding. The miasma released by millions of dead demons would polluted and potentially corrupt heaven itself.
The angels reside in the air/heaven. So they don't want to ruins their home. But the earth, well, that's fair game.
[Answer]
I'd say the demons exist underground. They can pop up anywhere but to really fight them you need to enter the tunnels and then air power means nothing.
It's a bit like the Vietcong who had whole cities underground to avoid bombing.
[Answer]
The angels need holy power to even harm the demons but it isn't permanent. Holy arrows can't hold much of this fleeting power and it's weak when it hits the demons. A single holy arrow can only harm demons and dozens are needed to kill one.
The angels don't have a unlimited supply of this holy power either. They can't fill many bombs with holy power before fatigue takes over.
Swords don't have this problem. As long as it is in the hands of an angel it will be filled to the brim with holy power and can kill demons with a single strike.
To increase the need for a swift melee kill, here's another idea. Hurt demons release a miasma. Killed demons doesn't.
[Answer]
The wings are the wings of Mercury which is the attainment of the 'mercurial mind' or Christ mind.
So the Air is the mind element as the water is emotion. All these terms referred to in your first questions are metaphorical representations of the mind.
The holy Angels have spiritual attainments of the mind which are far superior to most all men and demons except those few who fell from the highest planes with the highest knowledge or the highest attainments of the spiritual mind which then got used for evil destructive purposes in the astral and on the ground.
And remember the fight is over incarnate humanity who are a mixture of Angels and demons "on the ground" as you put it so well.
Some human beings on the ground are angels and some are demons of various levels of mental and spiritual attainment.
So, why is Air superiority not always adequate to defeat demons? If it is perfected, Air superiority will always win. If it is not, a person on the ground can be tricked / tripped up by a crafty fallen angels /demons on the ground and in the astral plane. The striving soul on the ground is attacked from both planes by wicked humans/angels incarnate and wicked angels discarnate.
Spiritual perfection - the attainment of the 'wings of mercury' - is the only state of invulnerabily. "No weapon formed against ye shall prosper". That is, no demon in the astral or on the ground shall defeat you. The state of spiritual imperfection - no wings for the navigation of the Air - is one of extreme vulnerability.
Edit:
thnx 4 the welcome A4android. I'm unable for some reason to add a comment under your reply so here it is in an edit: Yes "air superiority" of the angels is spiritual perfection - they have perfected the soul and mind by allowing the Christ Mind to enter in and regenerate the whole 'man/woman'. For those of us who fell into the lower planes of matter - all of us here on the 'ground' - there is a way back. It's a path, takes time.
I should have been clearer on a couple things earlier. I wrote: "The state of spiritual imperfection - no wings for the navigation of the Air - is one of extreme vulnerability." Due to the fact that spiritual imperfection is a relative state - some more or less than others - vulnerability is therefore relative - some more or less vulnerable than others. It is why, on the ground, in a relative state, we need angelic allies to guide and guard us to the apex of being so that we too can earn our 'wings' on the way.
Cheers
[Answer]
Vietnam. Watch the Ken Burns documentary. Air superiority/power does not win real estate and secure long lasting strategic victory. The United States bombed the living daylights out of the North Vietnamese and the Viet Cong in South Vietnam, and still lost the overall strategic battle on the ground.
The real question is: Why are the Angels fighting? If they're fighting just to fight, then on a tactical level, the Angels will indeed have a fair amount of superiority in each battle and shouldn't ever really engage the Demons on the ground. But if their goal is to say take the Demon's territory and control their domain, then they will have to fight on the land. Additionally, it seems there would be some psychological factor among the mortal populace by fighting and being seen fighting among them, in person, rather than leaving them to deal with Demons/Devils. I'm not sure how demi-godlike your Angels are with their accuracy, but if they can engage Demons with Holy Arrows and Bombs and completely prevent the possibility of collateral damage among mortals, then they would avoid the "killing one non-com, creating ten enemies" situation the United States was in employing napalm, bombs, etc.
] |
[Question]
[
**Closed**. This question needs to be more [focused](/help/closed-questions). It is not currently accepting answers.
---
**Want to improve this question?** Update the question so it focuses on one problem only by [editing this post](/posts/8925/edit).
Closed 6 years ago.
[Improve this question](/posts/8925/edit)
Assuming for a second that our future won't be hijacked by [shackle-breaking AIs](https://worldbuilding.stackexchange.com/questions/8915/shackling-strong-ai-second-attempt), I'm planning a lighter segment in my story, which unfortunately for me involves children playing.
Now you would ask, what could be easier than children playing? Just give them a piece of chalk, a rivulet full of mud to skip around in, something. They'll keep themselves busy.
Yeah, sure, the problem is these kids are the grandchildren of people who are children today. **What will they do for fun? How will they play?** I'm thinking childish games (say ages 4-12), in a high-tech context. Kinda surprised this hasn't been asked already.
Any ideas?
And yes, I'm hoping they'll still occasionally skip stones or something, but I'm thinking some cool technotoys.
[Answer]
If my neighbors' grandkids are any guide, they'll play with the boxes and wrapping paper that all the fancy presents came in.
[Answer]
**Sporting Equipment**
* What are the popular sports in your future? Children will likely play with the equipment for those sports. This doesn't need to change, although the quality of the children's equipment will be a function of wealth.
* **Add robots**: while shooting free-throws by yourself might entertain some children, those who can afford to have a robot opponent when no other children are available will likely jump at the chance.
* **Add more robots**: running after a stray ball is a chore. Let's build a robot ball that can roll/bounce/fly back to you when it goes out of bounds.
**Make-believe**
* Dressing up and using various objects to pretend to be a chef, mechanic, soldier, or wizard is perennially enjoyable. Clothing and objects made for these purposes are generally enjoyed too (a stick can be a sword, but a plastic or foam sword is even better).
* **Add robots**: Noise-making guns are fun. Laser tag is even better. How about robot friends that will form an enemy army for you and your friends to shoot?
* **Add holograms**: Overlaying reality with illusions can make your make-believe even more believable.
**Miniature Worlds**
* Toy cars, trains, etc. give you control over something too big/important/expensive for you to play with in normal circumstances. Arranging tableaus has also been enjoyed for some time.
* **Add robots**: After setting up a road, how about the little toy cars drive around on them, stopping at intersections to let other robot cars pass, and generally creating a miniature world.
* **Add holograms**: Improve the scenery of your little world with projected holograms.
**Tabletop Games**
* Board games still get played now, even with computers.
* **Add robots and holograms**: Virtual presence is already a thing. When it gets cheap enough, we may all have suites of robot stand-ins available to represent virtually-present guests. Playing no-tech board game with such high-tech stand-ins may not be the most odd thing future generations do.
* **Add robots and holograms in a different way**: The clockwork elements of three-dimensional tabletop games are usually gimmicks rather than essentials to the gameplay, but if done well, there might be some fun and exciting possibilities. (See [Khet](http://en.wikipedia.org/wiki/Khet_%28game%29) for an example of using simple technology to add a real gameplay element.)
**Arts and Crafts**
* Drawing, sculpting, etc. are not going away.
* **Add 3D scanners and printers**: After making a sculpture in dough, scan it and print a solid, long-lasting copy. Maybe skip the dough and just design it in a computer and print out your artwork.
**Virtual Reality**
* Videos and video games aren't going away.
* **Virtual Reality**: I don't think we're all going to give up interaction with screens until VR becomes more convenient, but I'm sure we will start doing more VR as the technology develops.
[Answer]
I'm gonna go ahead and say it: **robots**. I wish the answer was more original but I'm afraid it ain't.
This is what is being developed right now. Social robots for kids, meant for social training (autism...), special care, or general education. It is more engaging than "lifeless" toys (ie. not social), more efficient than TV at teaching, more attractive than anything else.
Hasbro's Furby is on the cheap end of what already exists. For more elaborate stuff, the Personal Robots group @ MIT Media Lab has some good examples:
* [the huggable](http://robotic.media.mit.edu/portfolio/huggable/)
* [tofu](http://robotic.media.mit.edu/portfolio/tofu/)
* [dragonbot](http://robotic.media.mit.edu/portfolio/dragonbot/)
These — in their future versions — will basically be you best friends, your personal teachers, your health trackers, soft, fluffy and squishy for night time and shiny and fun for activities. And all that, specially tuned to the kid's needs because it learns from social interaction and cues.
**So what will they do with these robots?** That's the hard part I believe. Probably very "human" games. Things that feel very natural to us because evolution *meant* for play to be a learning activity. But probably the robots will be able to project a 3D environment around the kid to enhance both the experience and the teaching, narrate a story, add hidden tests and activities, put in a few words of another language...
**If you want some specific examples of games**, try and think about what needs to be worked on as a child. Motor skills, social skills, logical reasoning, all sorts of life skills (confidence, self awareness, creativity, ...), and any "bonus" skill you might want to throw in (music, 2nd language, programming, ...). And embed all that into the most engaging activities for kids, usually some sort of open-ended game like the imaginary adventures you might have had in your backyard as a child.
IMHO, the result of all that would be some open ended improvised game led by the companion robot in order to tune the level of the various variables to the child's skills.
[Answer]
Their parents old toys, new handmade toys, and Popsicle sticks.
To this day my mother tells folks about my first computer. As the story goes my father was building his first computer, and had given me one of his early test projects which was a 10 button keypad hooked to a counter and a light that blinked so I carried this with me everywhere telling folks about my 'puter. I don't remember this as I lost it before my third birthday.
I spent the holidays with family. Toys of choice: old cell phones, Legos, ceramic tile, anything with wheels, and the marble wall which was a salvaged car hood festooned with magnet adhered wood track to direct dropped marbles.
'A' wanted an iPod. he didn't git one because he doesn't listen to music. the only reason he wanted one was to show it off at school.
So for your story, Dad got a new \_\_\_, so the kids play with the old one, and try to connect it to the vacuum cleaner.
[Answer]
In addition to the high tech ideas presented, and the [Boxes and Wrapping paper answer](https://worldbuilding.stackexchange.com/a/8934/28789) that hopefully will **ALWAYS** remain true:
Consider the fact that at the technology-level you imply, just running around outside may be safer than it is today. Especially in cities, just playing outside has been reduced by more than the availability of computer games and TV.
The other part of it is the fact that streets are busy, parks sometimes far away, the next playground may not be safe to reach for kids alone, and/or be dirty, possibly to the extent of being dangerous.
So, parents would once again be in a position where they could say "how about you take your [vehicle of choice] and go to the [playground, lake, park...]" when the little kid is just *booooooooreeeeeeed* again.
Yes, they may take along their electric pet-dino, but I think when given the opportunity, kids will happily be outside climbing, running and meeting friends no matter the tech-level.
In the case of worried parents just have a drone follow the kid around... and the kid will be annoyed to **NO** end by it ^^.
Have them play "ditch the drone" and try to hide from it.
Inside-play: holographic stuff, yes, but also occasionally messy stuff. Kids will not only be drawn to images, they will drawn to textures, tastes, smells, too. **IF** they are being provided.
If you do not want to display them glued to a future console, try to imagine having one of the whiny, console-addicted kids at home... and then the console breaks ;).
[Answer]
An immersive virtual reality where they can be an officer (like in a real time strategy game, e.g. Starcraft 2), a hero (a first-person shooter like Quake), or a general (resource management games like Pandemic 2). So the general could dispatch an officer to conquer a location, and success will be determined by the officer player's skill. The officer could send a hero out to attack a location and success there could be determined by the hero player's skill. The social ability to recruit good officers and heroes will be critical to a general's success, but good resource management matters too.
Note that there can be other variants as well. Perhaps heroes have swords instead of guns. Or wizard's wands. Or a mixture of both. Or all three (guns, swords, and magic).
Players will be able to choose the rules of the game. So someone may start a server that uses Weber and Evans' Hell's Gate/Multiverse series as background. Or Saberhagen's Berserker series. Or Pratchett's Discworld. Or something entirely different, like rock stars or fashion shows. There may even be parentally approved games where they learn math, grammar, and home economics skills. Or wander around the Jurassic with dinosaurs.
The key advance here is to allow friends who like different things to participate in the same game together. So if one likes strategy games and the other likes first-person shooters, they can still interact in the same game.
[Answer]
**Thought 1. Automation.**
A big push in virtually every industry is to build [machines that do work for us](https://www.youtube.com/watch?v=7Pq-S557XQU). Even work that requires thinking, knowledge, and judgement. I'd apply this to sports... which I hope is something your world's future generations still partake in.
Here, you could have sporting equipment that know the rules of the game, and are their own referees. Basically, automating away the need for officials.
Simple example; basketball. Imagine putting an accelerometer and simple computer in a basketball that can feel the bounces, passes, and shots of the player holding it. It'd be able to discern if a player is running with the ball (not allowed) and signal to the relevant hoop to disallow points to be scored until the ball is handed back to the other team.
A quick Google tells me this exists in [rudimentary form today](http://en.wikipedia.org/wiki/Goal-line_technology).
**Thought 2. Kiddify technology in your plot.**
This example kinda' makes some sexist assumptions, so take it with a grain of salt and adapt it to the level of social injustice present in the world you've built.
Today, young boys often play with toy soldiers, tanks, planes, etc. Collectively I'll call this "war-stuff." Fifty years ago, young boys played with war-stuff appropriate to that time period (Korean and Vietnam wars, the Cold War, and arguably the Apollo Moon missions too).
Given the propensity of society giving boys war-stuff, I see no reason why this wouldn't continue a hundred years into the future.
[Answer]
**Add popular culture:** Just to note. My kid (2.5 yo) totally loves the movies from [Cars](http://en.wikipedia.org/wiki/Cars_(film)) franchise.
When I was young, I totally dig the [Krtek](http://en.wikipedia.org/wiki/Mole_(Zden%C4%9Bk_Miler_character)) fairy tales.
And when my mom was young, she was also influenced by popular culture.
So, what is popular in your future? Is it space exploration? Then popular-astronaut action figure is a must.
Is it sports? Then [blernsball](http://theinfosphere.org/Blernsball) themed toys are the most popular.
You get the idea?
[Answer]
I agree it might be unexpected (and possibly not what the parents intend), but reckon it'll be subject to a few influences:
First, what they *want* may be driven by marketing - there might be a cool gadget that's fairly useless but successfully tied in to a popular show. This doesn't mean they won't repurpose/rename them, e.g. Captain Stargazer now inexplicably runs the farm with the plastic sheep (along with a themed-Lego husband who is a quarter of her size).
Secondly, even the simple stuff they like (and "misuse") might be more technological. For instance, what if there were wrapping paper that reacted to touch with rippling patterns? What if there was a holo-projector that projected a blank rectangle when not connected (like a dial-tone on a phone)? You could have children running around with their "hi-tech camouflage" and their "laser shield", etc.
[Answer]
I think it was Stross who took this to its logical conclusion: in the post-singularity future, we will be essentially immortal and free of resource limits. So, wargames. Running around and killing each other in some form of arena/battlefield combat. Not virtual at all. Making an art of it. Getting body-modded into a death machine, having fun killing each other and getting respawned, then going back to whatever other form works best for your next task. Or indeed, as others have written, dumping the body off when you're done with it and returning to a purely virtual existence.
Nearer future: immersive alternate and augmented realities; reduced violence and freedom of movement to the point where they aren't even permitted to interact directly at all for fear of contagion, and aren't allowed out of doors until the age of consent for fear of boogiemen.
[Answer]
>
> Just give them a piece of chalk, a rivulet full of mud to skip around in, something. They'll keep themselves busy.
>
>
>
Just curious, how many kids *now* do this?
Mostly they play videogames, or whine about not having a cellphone.
---
Electronic toys, or nanobots. :) Depends on the tech level. If you've got non-shackling AI, then they'll be playing with their imaginary friends. Who'll be much more devoted to them, much more creative, and a lot more fun than meat-friends.
[Answer]
Children just invent stories around what they observe from adults.
* They put plushes in line and play teacher
* They make a house in their bedroom with a chair and a blanket
* They fold a piece of paper, draw little squares on one half and a big rectangle on the other half and pretend it is a laptop
Children need to express their creativity and they do it to a huge extend if adults give them the opportunity.
[Answer]
In the world of [Mega Man Battle Network](http://megaman.wikia.com/wiki/Mega_Man_Battle_Network_(series)) (set in the year 20XX), kids have sentient A.I. buddies called [NetNavi](http://megaman.wikia.com/wiki/NetNavi)s and they hang out on the 'Net (the new Internet, which is in 3D) via their Navis. A lot of kids also use their Navis to NetBattle in a 3D colosseum that can be hosted at home, in designated battle areas on the 'Net, and in arcades.
Really, Navis are friends, assistants, allies, &c in this world. I personally don't see A.I. as entities who want to kill us, so I think kids'll be fine. However, humans are the ones making A.I.s and *we* are capable of killing, so it's hard to tell. Anyhoo, this is what I think, haha. There are many good answers here though.
[Answer]
As much as my kids like to play games, listen to music and communicate via Pod, Pad or phone, the boy's favorite will always be their soccer ball and rugby ball. And for my daughter, nothing is more magic than horses... So while technology will continue to become faster, smaller and adding features (I reckon voice recognition and virtual reality will be as normal as high resolution touch screens are today), I don't think the "established" toys and play things will disappear at all. And that includes, chalk, bicycles, paper and crayons etc.
[Answer]
Electronics are very available already, and will be even more available in future. I just got rid of two old laptops and one desktop PC, which were all still functioning. In my little 2-person family we are still left with 3 laptops, 1 desktop, a smartphone, a "non-smart" cell phone, and an additional cell phone that still works, but is not used. Oh, and two game consoles and a gameboy. All this builds up over time, we are not exactly prone to regularly buy such things.
This is very different from my childhood. While I had a gameboy and a PC by the time I turned ten, electronics was still rather sparse at my family. I think I didn't have a cell phone at all until I was something like 15.
My nephew is 2 now, and just starts speaking. However, he has been playing with phones basically since he was able to hold one. That means playing to talk to someone on the phone. He wants to watch lullabies and cars on Youtube (Yes his parents show him lullabies from Youtube, you read right. He wants it, and it works in putting him to sleep). He knows how to operate a tablet, and plays simple puzzle games (put the car into the right hole) on it. He likes to play with remote controls of the tv.
While things like Lego and chalk don't grow old, I would expect the shear amount of old smart phones, tablets and other electronics by the time our great-grandchildren live means that kids will have a personal electronic device as soon as they can make use of one. You will, like today, have children that play more with such things, and others who are more interested in other things. But electronics will be widely available, powerful, and it will be used. And sometimes kids will just hold the phone to their ear and pretend to talk with Batman.
[Answer]
*Classics never die, they just get reimaged*
**Gravity box maze puzzles.**
Think about those handheld gems we grew up balancing between our hands to get the tiny metal ball to follow the clear plastic maze without going too far down the wrong path. Now see them as a gravity box where there is still a maze inside the cube, and the twist is the little beebee has no gravity acting on it! You have the same wonderfully frustrating challenge of needing to enact a well aimed force just so on the ball without over shooting the impossibly tiny target hole into the next section of the cube. Impossible to put down until skill mastered. It may seem easy in theory, but one itty bitty touch of the beebee at the wrong time or direction and it's back to square one. Then, for more fun, you get to adjust the times g and start over.
**Etch-a-Sketch Glow boxes**
Another wonderful dexterity-challenging toy we continue to love is the Etch-a-Sketch. Only now we are working levers to act on a "drawing bead" that, as it passes through a mysterious, highly viscous fluid, causes the surrounding particles to glow (colors are customizable, of course). We thought ourselves quite the hot stuff to be able to get one hand to twist the "backwards" way while our dominant hand spun the dial the "right" way and vice versa to get that perfect circle. Well, our great-grandkids will scoff at that as they finally shape a perfect glowing sphere on their 500th try. Not to mention the fun of endless geometric shapes and patterns and arguments when a sibling grabs it and shakes it up and down, erasing a 1/2 hour masterpiece. Can 3D drawing be simulated on a tablet? Of course. But *this* is an Etch-a-sketch in your hands with real live knobs and filled with magic stuff that *glows*.
**Neon and Fruit-flavored Chia Pets**
Although not exactly a toy, learning botany has never been more fun than with the Chia Pets that grow organic fur and hair. This idea gains a great new twist with gen-mod varieties that include a transformation of the plain green grass "hairs" into brilliant neon colors at maturity. And what kid doesn't love enjoying the grape, lime, orange, etc. flavors of the edible versions of Chia cones and Chia bread. Sounds a bit gross, but the kiddies love it.
**Legos Solar System 2050**
As another answer alludes to, Legos are a classic that remains stylish. Legos Solar System isn't a game for tablets, though. It sticks with the tried and true block construction play, with the added features of semi-transparent blocks built on to-scale electronic bases that provide lighting and motion. They are modular to be connected into a working model that is very often seen hanging from ceilings in kids rooms and plenty of adult dens too. You can complete and hang your favorite rotating star or planet singly, but of course most everyone eventually builds the entire system. And yes, Pluto is part of the complete set.
[Answer]
It's rather easy, just extrapolate what we can currently see:
People are decadent enough, for having no real needs anymore. Instead they have artificially infused necessities, created by commercials. Thats the only reason, why useless stuff like smartphones is so wide spread, with some humans even selling their organs for having the money to buy one. Also everything needs to get cheaper all the time. And then we all know, that earlier toys where way too compicated! Modern PC-Games are so much easier than anything from the 80s/90s.
So I foresee that the kids in 50 years will play with naturally looking stones, made from plastic. Stones are easy to play with, and they are even cheap to construct, thus grantig more profit! There will be cheap stones, that any kid has, and there will be more cool stones that only the really cool kids have, with the only difference being the trademark logo. For we all know that coolness and style are the only things that count. No need for features, function or real differences.
Also stones won't overexert the little kids's minds too much, so the risk for them becoming intelligent or creative is lowered, making them easier to use workers.
] |
[Question]
[
As a scenario, let's say that a group of heroes is traveling in a hot air balloon as a proof-of-concept for bandit-proof travel. Some particularly well-armed bandits naturally have taken an issue with this, and are trying to shoot the balloon down with crossbows and/or longbows.
The heroes' hot air balloon is moving along at a pretty good clip, such that the bandits only have time for 1-2 good crossbow volleys, for a total of 8-10 bolts.
Assuming these conditions:
* Could they shoot down a hot air balloon with crossbows or longbows?
* How high must our heroes be to survive about 8-10 crossbow shots?
[Answer]
## They are safe.
A 1000lb medieval crossbow has an [initial velocity](https://www.youtube.com/watch?v=kHnZo6ELEV0) of around 150 fps (~45.7m/s). Oddly increasing the poundage of the crossbow does not increase the velocity just the allowable weight of the projectile, the distance traveled by the bowstring and the speed the bow can flex act as limits.
I will use the the formula for firing straight up because it gives the maximum possible height and is pretty simple [because stuff cancels out](https://www.omnicalculator.com/physics/maximum-height-projectile-motion)
$$
h\_\text{max} = h\_\text{initial} + \frac{V\_0^2}{(2\times g)}
$$
fired straight up with no air resistance, comes out to about 360 feet (110m).
A very low flying hot air balloon flies at over 500 feet (152m) -- legally they cannot fly this low today; during the civil war 500ft was considered flying low, 1000ft (~334 yards/ 305 meters) was more [common](http://www.civilwar.com/history/weapons-44543/observation-balloons-13305.html).
so even if the balloon is flying low, you are more than a 100ft short, If it is flying at a reasonable height the bolt does not even make it half way. And that is firing straight up to get the maximum height, firing at an angle means it gets even less height.
As long as they are flying more than about 360 feet up they are perfectly safe from crossbows.
As a side note longbows actually preform a bit better, they have a slightly higher max velocity, crossbows lets you fire *heavier* projectiles at similar velocities not faster ones. Longbows can manage 177 fps (54m/s) or around 495 feet (165 yards, 151m) straight up.
**So stay around 600 feet/200yards/183m/9chains or roughly a furlong and even the best archer on the planet can't touch them.**
[Answer]
Even if the balloon flies low enough that you can actually hit it with a crossbow or longbow (and it is surprisingly difficult to aim at a moving object above your head) you won't do much damage.
First of all at the top end of its trajectory the arrow or bolt won't have much penetrating power left.
And you will mostly be hitting the bottom and sides of the balloon envelope and holes there make hardly any difference to buoyancy.
Remember: hot air rises, so little would escape in downward/sideways direction anyway.
In fact: The envelope already has a wide opening at the bottom for the burner!
You best bet is to aim at the people manning the balloon and hope that they loose control of the burner when they duck for cover in the basket.
[Answer]
They are safe but for another reason than people have given
The balloon will be squishy and will flex went hit by an arrow. Think of poking a plastic bag.
If the arrow or quarrel pierces the bag it will get snagged and fill the hole it just created.
The balloons need to be fire retardant to avoid burning up from the fire keeping them aloft so even flaming arrows or bolts would likely be in effective since the flaming part would go out because (A) the oil or naphtha burns off and (B) the inside of the balloon is hot smoke so already has lower $O\_2$ content
Counter strategies by groundlings might be to fire weighed hooked arrows. if enough can be snagged in the balloon, the added weight will force the balloon lower and slower. making it easier to hit.
[Answer]
## Of course they can. If it's very dry, anyway...
The archers don't wait for the balloon to arrive. As it appears on the horizon upwind of their chosen hunting ground, they strike! They shoot bolts at the dry grass of the opposite hillside. From powerful incendiaries, flames spread quickly, climbing the bone-dry hillside as the horrified passengers of the Bandit Proof Balloon's maiden voyage watch helplessly. The wind draws them ever forward to the fire, at first with indifference. As flames tower high into the air, cold air is sucked in beneath, creating a windscape of treacherous downdrafts that suck the balloon toward the worst part of the fire. No hot air balloon can remain aloft in a column of superheated air.
Bowing to inevitability, the captain makes an emergency release of air, setting down to pay the ransom rather than chance his fate to the flames.
[Answer]
*Please note, this was done with "seems right" figures. There is actual maths performed elsewhere, including the base of my answer. I am intentionally leaving it here, without editing my "seems right" numbers, both for archival purposes and to not have 3-4 homogeneous answers.*
---
**First, the distance**
So according to a [random page from google](http://www.crossbowbook.com/mobile/range-of-the-medieval-crossbow-21.html) a medieval style crossbow had a total range of 380-390 yards.
So shooting up will take some distance out of it, but the bolt is "relatively" light, so lets round it to a nice 350 yards.
**Now, could it take down a balloon?**
The answer is "that depends". In short you'll want to have it puncture/tear a hole/several holes that leak more hot air/floaty gas than can be replaced.
I should imagine the hole made by a standard crossbow bolt is rather small and the material should be rather durable, both as defence and necessity to prevent "minor wear and tear" type things from causing a critical failure on the balloon.
Your bolts could have a *very sensitive* mechanism that will cause it expand into some claw like fashion for maximum tear potential upon hitting the fabric/balloon. This will increase weight, and cost, of the bolt so we'll now round the range *further* down to 300 yards.
**Can 8-10 bolts take down a balloon?**
Ultimately, it's your story so if you say it can, it can.
However, bolts are rather slow to reload so you're better to have 8-10 *people* fire once rather than 1 person firing 8-10 times.
With the assumptions above, it definitely seems plausible, presuming they're in range.
**TL;DR**
8-10 *people* shooting a specialist bolt should be able to take down a balloon from within 300 yards with a solid degree of plausibility. Their effectiveness is increased the closer they are as it's likely they can punch through both sides of the balloon.
**Addressing comments**
*Hot air balloons fly between 1000 and 3000 feet*
According to google, 1000 feet is 333 yards, so that puts the lower bound of flying into the upper bound of "lucky shot".
If this is going to be a hard constant, it turns "plausible" to "highly unlikely".
You mentioned this is a prototype, so I'd wager they'd be rather hesitant to fly too high for fear of coming down *hard*. That would mean your bandits stand a chance if they stay just above the treetops or lowish over hills/plains.
*Can a medieval person find wind currents?*
Predictably, maybe not. But it won't take that experienced a pilot to quickly figure out that different heights tend to have winds that blow different directions and act accordingly. This method is used by *birds* so I'm sure a human can figure it out.
A *skilled* pilot may be able to predict these with more accuracy. Even if it's "mountains tend to make the balloon want to go *direction*" rather than a scientific reasoning.
---
Please note, no maths was actually performed so actual results may vary significantly. I just applied some common sense "fridge logic".
For actual maths, please see John's answer, the result is quoted below:
>
> As long as they are flying more than about ~ 120yards up they are perfectly safe.
>
>
>
>
> As a side note longbows actually preform a bit better, they have a slightly higher max velocity, crossbows lets you fire heavier projectiles at similar velocities not faster ones. Longbows can manage 177 fps or around ~165 yards straight up. So stay around 200 yards and even the best archer on the planet can't touch them.
>
>
>
[Answer]
If you compare a medieval archer to a real balloon, the balloon will win. But real balloons were made in the 1780s and your balloon is made in the medieval era.
Your balloon was was created by an inventor who does not have the scientific background, technology, supply chain, or infrastructure that the Montgolfier brothers did. The fact that it can lift a person off the ground at all is an astonishing futuristic marvel centuries ahead of its time. If the balloon can fly so high and so reliably that there is drama about whether archers will threaten its flight, then that is the sort of epic achievement that is worthy of a story.
All in all, a medieval balloon that can carry a person is in the realm of suspension of disbelief. If you want a balloon that can barely lift, or that sinks at the least convenient time, that's at least as believable as a balloon that keeps people successfully out of range.
[Answer]
Archers can't reach you once you're aloft, but you're *far* from bandit-proof. Balloons are extremely slow. Average balloon speed is under 10 mph for safe operation (during liftoff and landing you want it as close to zero speed as possible). A horse can trot at [8-12 mph](https://www.speedofanimals.com/animals/horse?u=i), and gallop close to 30 mph. Your balloon is also quite large and has nowhere to hide while aloft. That means that your bandits won't have much trouble following you (modern balloons typically have a "chase crew" that does exactly this, to give the passengers a ride back to the starting point). You have to land eventually, and the bandits will be right there waiting to shoot you down the moment you get low enough.
The only way to be bandit-proof is if you escape over mountains, a large body of water, or some other impassible terrain. You're at the mercy of the wind, however, so there's no way to know in advance if you'll sail over the impassible mountains or into the very-passable prairie. There's also the inherent danger in being blown towards a mountain (crashing or being swept up higher than your balloon can handle) or out over a sea (stuck with no way back to land).
] |
[Question]
[
I'm working on a world where, with very few exceptions, metalwork is not possible/unwanted, and I'm trying to figure out what major differences one might see in daily life, and what would be necessary for a culture to continue to go without metal.
Considering a culture that is premodern but relatively advanced:
* Is it possible that metallurgy would remain unknown to a culture with many other scientific discoveries under its belt?
* What sort of every day items would be different or impossible to create without metal? Would something like glassmaking, for example, become impossible?
* What would be the standard substitutes for metal objects? I'm thinking stone, wood, and bone. Is there anything else? If certain magic and alchemy replaces the role of metal in society, what would it need to be able to do to be so superior that people would choose that over metallurgy?
* How high could buildings get?
* Would a world in which ore is extremely rare be different in any other significant way?
There may be other considerations I'm missing. I'm less concerned with the specific bullet points as I am with figuring out what changes when metal is not in the picture.
~
I should note that this is a high fantasy setting, so technology will still be limited to pre-industrial age levels. I managed to delete that info while editing.
[Answer]
How advanced can they get? Very.
The most advanced non-metal using cultures known where those of Meso-America culminating in the Aztecs/Mexica. The Aztec capital of Tenochtitlan is estimated to have had a population of 200,000-300,000 right before it fell to the rebellion. The city was built on manufactured ground, in the middle of a lake. It's fresh water supply came from several large aqueducts. A vast network of paved roads connected the entire Aztec empire together. They build bridges that spanned farther than any in Europe of the day.
In addition to metals, they also lacked beast of burden (horses, oxen etc) and the variable terrain made wheeled transport, even with good roads, impractical. (That's why the burrow is so strongly associated with Mexico to this day.)
The successive civilizations of Meso-America substituted large amounts of skilled and highly organized labor for metals and work animals. Stone was split to rough size with fire and soaked wood wedges. Then it was simply hammered with other stones repeatedly, crushing off the outer layer until the smooth surface was reached. It took a great deal of time and skill but some of the results are comparable to at least early industrial methods.
In fact, it has been hypothesized that the availability of cheap labor in the form of slaves, slowed and even stopped technological development in the classical world. Don't need a new gaget or a new material when you can just throw more people at the project.
Technologies:
* Glass: Glass doesn't require metal as a material but working it to any degree would seem to require metal. For one thing, you need some long thin strong tools to manipulate molten glass at at a remove... that itself would not melt or catch fire. Glass itself was known since neolithic times but it only became a common substance in the Classical era. That suggest it needed metal tools to get rolling.
* Ceramics: Not really metal substitutes. Although this or that ceramic may have this or that property of this or that metal, no ceramic has all the properties of any metal or alloy. There isn't really any function for which a specific ceramic would be a drop in replacement for metal.
* Electricity: That would be out unless you postulate some kind of organic conductor.
* Wood: Wood can and did substitute or preceded metal. In principle it can substitute almost entirely for metal in any structural application well up into 20th century levels of technology. If you had cheap labor, you could make elaborate but strong and lightweight structures like those used in the first 30 years of aircraft manufacturing.
+ Woods can also be hard. Ligum Vitae was a wood used for gears and ball bearings well into the 20th century. Bamboo substitutes for metal to this day in much of Asia.
+ On the other hand, working wood without metal is hard. Northern Europe remained sparsely settled well into the second millennium largely because of the inability of bronze tools to cut down oak trees for wood and field clearing.
+ But, if you postulated that the wood digesting enzymes of the various microbes that eat wood were readily available, it would be possible to work wood much like we work plastics today.
In any case, such a civilization would likely follow the Japanese model in which structures are continuously rebuilt instead of preserved. (Japan lacked hardwoods so no wooden structures lasted.)
Extrapolating from historical models, a low-metal society would likely be highly structured and hierarchal, with skilled and unskilled human labor substituting for the abilities of metal. In essence, the society would be mostly software with ver little hardware. Any disruption in social organization could lead to a technological and economic collapse. That seems to have happened in the Americas over and over again.
I would suggest starting with a study of Meso-American societies and think about how they might have developed further.
[Answer]
Assuming there's only trace amounts of metals (enough for life but not enough to work with), there's some stuff that could possibly be replaced:
* Blades and cutting implements could be fashioned out of volcanic rock. Since the flexibility of molding isn't readily available, they would be limited to shapes and sizes that can be sculpted. They would also probably be quite heavy - while there are lightweight rocks, those rocks are usually not the sort you can sharpen.
* Engineering would *have* to develop very careful sculpting techniques; again, without molding (which may be possible with stone and wood, but doesn't give you very sturdy structures and is probably a lot more complicated) you have to make the most of the matter you've already got clumped around. If you can't precisely control the shape and features of parts for machines, they're likely to be much larger and much slower to compensate.
* Glassmaking wouldn't be impossible; if you can make fire and have sand available, it would probably work. You can get tubes from reeds that you cover with some kind of dust (or harder glass) and probably have to swap out a lot more often but I guess it could work. Alternatively, you could sculpt a glass-blowing structure.
* Everyday items would probably be all wooden and made from interlocking pieces or sculpted out of large blocks of the material. That could work well enough. Some pretty advanced engineering understanding of forces and material strength would be required to get reliable machinery just out of interlocking parts though (they're probably be very good at limiting the directions of force vectors due to loads and redirecting them to reinforce the structure rather than pull it apart).
* In general, you'd have to use volcanic glass and sharp stones for rudimentary tools, use large stones and sculpting to get structures and heat-resistant machines, wood for everything that doesn't have to be sharp or heat-resistant and bone for convenience (bones are hard but they can degrade and they always come in either cage/enclosed shapes or long stick shapes - bone dust however might be useful if you grind it down and apply paste or something). *edit- outis in the comments provides examples of weapons made from wood and volcanic glass and has also posted relevant links - see his comments for more.*
* Buildings would probably not have limitations on their height, but they would in the structure to get there. Think of the egyptian and mesoamerican pyramids - pretty tall, but not exactly blocks of flats. You *could* get concrete though I guess, so if you find a good strong substitute for metal supports (perhaps, have some way to force crystalline structures, like titanium or diamonds have, on molten rock, you might be able to get materials strong enough for this). *edit- However, in the comments outis warns that there is a height limit for pyramids and you can support concrete buildings differently or not at all - check his comments for more details*
In any case, considering that metals are pretty important to biology and that despite needing trace amounts, they have to be pretty abundant in nature, I'd say that it isn't likely that you have biology like ours but so little metal on a world that it's practically non-existent. You *could* have a world where the metal on the upper layers has been stripped by previous inhabitants and the present ones use the metals in the biosphere's cycle to survive, completely unaware of what a metal even is.
It *is* however unlikely that you could get very far without thinking of, or trying metallurgy, even if there's very little metal around. As you can see, you still need to be able to work a forge of sorts. Heating materials is a great way to remove impurities, reform and combine them, so you'd have the necessary technology eventually no matter what. If it was just some rogue group that was trying out the tabooed practice of smelting metals from ores and using them to craft tools or weapons, they'd eventually motivate everyone to do that - it would be *too effective*. Imagine medical tools for instance.
[Answer]
I think that this question is leaning too heavily on preconceived notions of "how things work" and overlooking possible solutions that are outside of its box. Just because human technology developed in a particular way, that does not limit technological societies to developing in exactly that way.
For example, a society where metalwork is not possible might find biological solutions to problems. A world with a rich biosphere would give plenty of puzzles that would push the development of chemistry, such as "What causes bio-luminescence?"
There are also quite a variety of different naturally occurring rocks. Flint, slate, obsidian, marble, and (as Pipper Chip pointed out) obsidian are all extremely useful materials (even today).
Glassblowing does not require metal tools, it only requires a hot-burning energy source such as coal, a plentiful supply of an appropriate sand, and tools that will hold up to the required temperatures. It might not be easy, but it should be possible.
Another area where such a civilization would probably be very strong is in ceramics. Though not as strong as metals, they can still fill many of the roles that metals fill in our society such as [knives](http://en.wikipedia.org/wiki/Ceramic_knife). Plastics are another possibility.
Eventually, the society will discover metals and though it might not use them the way we do, they could certainly master them well enough to create electric circuits.
[Answer]
A world without metal is a very troublesome world indeed. For a short answer, the most advanced stone age (I say this loosely, as the official stone age ended millenias before) is the mesoamerican civilizations (Mayan, to name one), which was pretty advanced. They didn't have metal tools at all. Their primary tools were made of stone, hide and rubber.
Now, imagine a world without metal:
1. No wagons. While carts are possible, wagons would be too big and too heavy for oxen or horses to pull. This is because they will be using stone connectors and poles for the wheels. While the wheels itself can be carved of wood, it can't be used for connections. You see, wood is not slippery, even if you sand it properly and apply oil on it, the friction will cause it to burn after a few hours of travel. Middle age wagons solved this problem by applying iron to the parts that rubs with plentiful application of grease. This was probably why the Mayans didn't have any wagons.
2. There is no problem with making glass, as metal tools are not necessary for making glass. To substitute metal, you can use carved wood, covered in resin, like the Chinese lacquerwares.
3. A world with no metals, will suffer malnutrition. If your population is human, then they will need carbon and iron as primary nutrition. In our world, we take that for granted. In a world without metal, the absence of iron will kill your people as we need iron to make red blood cells. If we assume that there's just a little bit of iron in your world, then we can already imagine the world to be somewhat barren, with trees stunted, its people small and out of breath easily. It's the same if you make plumbum your people's necessary element. I believe the only way such worlds can thrive, would be if they're silicon based organisms, substituting iron with maybe acid or helium to carry the necessary gas to the cells.
4. It also means that unless the structures they built are made of wood, it will take a very long time for them to even build a city hall or temple of stone. Let's look at the example of pyramids. It took them decades just to build one, and that was with the help of iron/bronze tools. We know sculping stone using another stone is way harder, so it will take them maybe 4-6 times more than their iron counterparts (I'm pulling this number out of my backside). Nobody can tell for sure how much longer they will take as archeologists haven't agreed on the time it took the mesoamericans to finish one of their pyramids, but you can tell that it's definitely a long time, and it's smaller than their Egyptian counterparts.
Still, if there's actually minerals in the ground and that your people haven't had the knowledge to use it yet, then you can kick my 3rd point away. It's still going to be a very harsh world to live in, as evidenced by how bronze age made stone age extinct and iron age made the bronze age go extinct. If there's magic though, then they can remove stone altogether and just use wood. A house made of wood is actually very sturdy, sturdier even than stone buildings in earthquake prone areas (depends on the building methods). A spear made of sharpened wood, charred on fire is just as sharp as an iron spear, though obviously not as hard. Also, you don't need iron to make bow and arrows. You can make both bows and arrows by only using rocks and fire.
[Answer]
Just a brief comment on the glassblowing...
Naturally occurring stone tubes form in limestone caves, as water drips through the centre of the tube... like a thin, hollow stalactite. I think they are called straws.
They aren't usually very big, and you have scope within fiction to modify this in many ways.
So that gives you a heat resistant tube you could blow glass with.
Regarding buildings - The cathedrals of europe were built using intricate timberwork, held together with oak pegs. If you can bore a hole, then you can dowel and peg joints. That should get you buildings as large as you need.
As for boring holes - well the best drills I use today are tipped with diamond. If you have good access to diamond or carborundum (ruby/saphire etc) then you can drill or cut nearly anything, and polish to a mirror finish. Stone cutting wheels are still made of bitumenized cloth, loaded with mineral abrasives. I do carve stone, and for detail polishing I use rubber blocks filled with corundum powder. Natural latex and powdered diamond?
A note on sophistication - I am led to understand that the mesoamerican cultures produced aspheric lenses. They had the skill and knowledge to produce sophisticated optics, that have only recently become available in our society.
Given that glass is an option, and sophisticated optics are possible, and crystals are permitted... well it's not a big stretch to turn a simple rod of ruby into a laser, if you can get enough power into it... like a bright enough light. Fibre optics? Broadband? Semiconductors? (silicon crystals)
Many of the minerals we are familiar with involve traces of metals... metals that we are not familiar with, such as gallium. Would those elements be available, though not "refined" as pure metals? That would give you access to pretty much the entirety of modern computer tech. Microprocessors are made using photo etching systems on amorphous silicon.
Possibly the trickiest bit would be connecting into the silicon, which is currently done with gold wires. Well gold is one of the few metals that is found in nature in a pure form - no refining required.
Unless you are going right out of the universe, remember that iron, with an atomic weight of 56, is the most stable and therefore most abundant element in this universe. Heavy elements, like uranium, break down until they reach iron. Light elements, like hydrogen, fuse until they reach iron. The universe produces iron. That's why our planet is made of it, which is why it is magnetic.
Even if you have a planet that is iron scarce, iron just falls out of the sky. Many tales of swords forged from sky iron, or shooting stars. Meteorites are mainly iron.
So much for my brief comment! Good luck.
[Answer]
I agree with certain aspects of many of the answers, but feel like by default we are limiting ourselves to preconceptions of how technologies were unlocked, perfected or utilized.
Think of many of the things we are discovering the unique material properties of today and apply that to a people who have survived off them. For instance, spider's silk is something we are discovering the uses of but has been in existence naturally since prehistoric times. It's stronger than steel and almost as strong as synthetic materials like kevlar, which is woven to make bulletproof vests. Spider's silk is also a conductor on par with copper, so I'd say circuitry is also not an impossibility. Carbon is a vastly abundant material that occurs in so many natural and unnaturally occurring allotropes, with varying material properties. We arrived at some of these with technological advances that probably relied upon devices using metallurgy but didn't necessarily have to.
To say that a world without ore (iron, copper, etc) would result in the end of humans with blood using iron as an oxygen-carrying element is a bit close minded. I'm alive and surviving right now and healthily and haven't had to munch on iron ore to do it. Our iron is 'trapped' in a biological cycle and I don't think melting people down would result in an iron yield enough to forge weapons or anything useful.
One thing not addressed is the establishment of measurement for the advancement of a culture. Are we saying that it's the invention of technology or the ingenuity of it? Is it technology which benefits and creates, kills and destroys or both? Even some of our most destructive weapons can be achieved without the use of metallurgy. Is the advancement of a culture based on wealth? Salt was used as currency before precious metals and was worth more at one point. How about longevity? Some primitive cultures have been around much longer than the technologically advanced cultures that have risen and fallen.
The main point of all of this is, for a high fantasy setting story, by omitting the use of metallurgy we are creating an opportunity to reinvent technology. I would assume that you aren't writing a manuscript on how your civilization created each of their technologies and in a fantasy world, small gaps would certainly be allowed.
Some notes to add. Spider's silk though may not have compression strength for load bearing, it's tensile strength is immense and its toughness is also incredible. This to me gives ideas for armors, for structures can be used for tension lines. In combination with some ideas that Raven has proposed I'm sure a makeshift circuit could be combined with optics, certain sapphires or rubies (gain medium) and others to craft lasers which either relied upon the sun's power or some other energy source.
Diamonds are a naturally and have so many uses it's ridiculous, they're thermal conductivity and optical properties are great. Using diamond powdered tools like saws to cut massive stones could be achieved like how we theorize the Egyptians cut stones using sand and saws. Acids also provide a whole world or creative alternatives to metallurgy.
Ceramics are another versatile inorganic nonmetallic material. Bricks are ceramics. We can make firearms and knives using ceramics. Tank armors designed to withstand anti-tank missiles are also made using specialized ceramics. Bladed weapons could be forged from multiple materials at once using different properties to achieve near metal results. The Japanese use different soft and hard steels to forge a single katana so that the advantages of one cancel out the disadvantages of the other. Why not use a combination of ceramics, obsidian, glass and wood or bone to achieve similar results.
Explosives are and can be used and created without metallurgy. This can be used for both shaping the earth and as a weapon.
[Answer]
The limiting factor on building height if you don't have metal is not structural strength. Ancient Roman apartment blocks could reach heights of 10 stories; 12th-century Italian towers could go as high as 30. These buildings were made using a mix of stone and wood -- the first iron-framed structures didn't appear until around 1800.
The limiting factor is access to the upper stories. Without metal, you can't (easily) have powered elevators, and stairs are only practical for six floors or so.
[Answer]
Many of the other answers already cover most of what I wanted to say, but there's a few points I wanted to add here.
The first would depend on your definition of "no metals" would be. Imagine a world where metals of any sort were extremely rare, life as we know it would be completely different assuming it could still function on the scale that we know. First is that our entire planet would likely behave differently since its magnetic field would either be missing or weak.
However what if we instead said that metal exists, but aside from going very deep, it only exists in tiny amounts. That way we could account for the metals needed to sustain life, as well as other important factors that keep our planet in check. There are many areas around the world where metal just doesn't exist in abundance near the surface that you could model off of.
One interesting twist would be to have a rather abundant sources of a couple different metals that we would consider rare. For example, having just gold means you could eventually have computers however it wouldn't be nearly strong enough to work as armor or weapons. Without effective metals to sink heat, computer would also then be limited to their overall heat output so high-powered applications are out of the picture. There would also be no magnets due to the lack of iron, so things such as a motor are out of the picture.
Another thing is **concrete**. You don't *need* metals to work concrete, and it technically doesn't need reinforcement. The Romans even found that by adding volcanic ash to their mixture, their concrete stands up to the erosion of water fairly well. Of course, without reinforcements the concrete will have some major issues to contend with. First thing is that concrete will completely fail when bending, making tall structure at a high risk to high winds and possible earthquakes. It will also take a lot more concrete to make a given structure stable. Pillars have to be large and wide to make up for the lack of metal reinforcements, and [according to this article](http://simplesupports.wordpress.com/2013/06/25/the-truth-about-roman-concrete/) it would have to be about 5 times larger to be as effective as concrete with steel reinforcements, but would still be susceptible to the bending issue.
Also let's not forget the potential for **rubber**. This is a modern way to allow concrete and masonry walls to reach greater heights, by making them flexible. In modern construction these are called control joints. If the wall moves from an earthquake or just thermal expansion, or ground settling, the rubber stretches or compresses so the bricks don't crack.
Rubber derives from a tree and can be processed without the use of metals. One obstacle to rubber is that you would need to be in a climate and terrain which supports rubber trees—assuming metals in your world allowed rubber trees to evolve. Rubber has many great uses but those wouldn't necessary replace any of the uses of metal.
[Answer]
Harry Harrison explored related themes in his *West of Eden* <http://en.wikipedia.org/wiki/West_of_Eden> series in which the 'dinosaur killer' never struck and dinosaurs went on to evolve an advanced civilization built on bio-technologies up to and including boats, submarines, projectile weapons, and remote sensing systems based on bio-engineered lifeforms.
On a separate point: none of the answers given so far mention stone age developments in aerodynamics. The boomerangs used by Australian aboriginals come in a whole range of purpose-built forms for recreation, hunting and warfare are strictly a sticks/stones/fire technology. Yet, all embody sophisticated appreciation of the properties of aerofoil surfaces, and the consequences of displacing the centre of dynamic load from the centre of mass of those aerofoils to get the desired characteristics for control of dynamic behaviour e.g. a hunting boomerang used against kangaroos is not intended to return to the thrower while one for hunting birds should return if the target is missed.
[Answer]
Consider the societies of the late stone age in the real world. Neolithic farming societies had access to many inventions and discoveries that we don't generally think of as "stone age":
* cities
* pottery
* wheels
* farming
* woven cloth
* writing
[Answer]
You can look at the old societies pre 3500-1200BC to get a pretty good idea of what they could and could not do without metal.
If metallurgy was replaceable by magic on earth a vast majority of people would choose to use magic. If they themselves could not use magic but a shaman could then they could pay/barter with him to do whatever it is they want.
Buildings could get at least as high as our modern barns for area that need a lot of interior space and a somewhat higher if you are just going for a tower. However, it would have to be a lot harder to construct very large or tall building without the use of metal.
I think in general though this world would be pretty intertwined with the magic or with nature or both. Those societies would probably have a low population concentration and have to live in spread out communities with low roof buildings. They would only be able to use rudimentary farming methods to make food for themselves.
If you want to have a large population of these people they would probably have to be nomadic and sort of travel around eat everything in one spot then leave it for some years before it all grows back.
[Answer]
Raymond E Feist's Magician had a concept similar to this if you want to read it in which an alien race known as the Tsurani (whom had tech levels similar to the Romans but with access to Magic) come from a world with very little metal. Mostly they use a special wood which when treated with a resin makes the object very hard (they use it both for armour, swords and pottery etc.) It's been quite a while since I've read this book but I'm pretty sure the second section of it goes into detail about their planet and how he has decided they constructed buildings etc.
[Answer]
Another problem for a world without iron is it would lack protective magnetic field. Magnetic field is created by iron-nickel earth core (<http://en.wikipedia.org/wiki/Inner_core> ) which creates magnetic field: <http://en.wikipedia.org/wiki/Earth%27s_magnetic_field>. It is extremely important for life: "dissipation of the magnetic field of Mars caused a near-total loss of its atmosphere". Main star's radiation would fry any life on such world. Life on a planet without abundant iron would have to deal with violent, DNA-damaging radiation. So it is about impossible.
Further reading: <http://en.wikipedia.org/wiki/Iron_catastrophe> - <http://en.wikipedia.org/wiki/Magnetosphere>
Your main problem in such world lacking iron is not having metal for tools: it is how to protect DNA of carbon-based life against radiation. Higher forms of life will have hard time developing because small forms (bacteria) are very hard to protect because they have small volume/surface ratio. The smaller the organism is, the harder it is to protect it from environment.
Physics. It just works. It is not opinion and not optional.
] |
[Question]
[
How effective would a cannon made of stone be? Would it actually fire? Would it still be usable after firing? Would it be as effective as a metal cannon? How thick would the walls of the cannon have to be?
[Answer]
Not very. Yes. Maybe. No. It depends.
* **Would it fire?** *Yes.* The powder charge would launch the cannonball towards the enemy. There might be problems with accuracy. And the cannon might burst, see the next point.
* **Would it fire twice?** *Maybe.* Depends on the strength of the walls, as you noted, and also on the presence or absence of flaws in the stone.
* **Would it be effective?** *No.* It would probably be harder to produce than a metal cannon, and heavier.
* **How thick would the walls have to be?** *Impossible to answer.* One might err on the side of caution, and make them *very* thick.
# Has it been done?
There is something called a [fougasse](https://en.wikipedia.org/wiki/Fougasse_(weapon)), which could be considered a stone cannon. Note that they were constructed in place, not mounted on a carriage for battlefield mobility.
[Answer]
In reading for this answer I was interested to see that [a comparison of cannon metal strengths was published in the New York Times in 1861](http://www.nytimes.com/1861/05/23/news/american-steel-cannon.html). This sort of thing was apparently considered to be of general interest. Which is very cool, and maybe a little sad - not for them, but for us.
There are several different qualities which comprise the strength of a material. Different qualities are important for different uses. An important characteristic for a cannon barrel is [tensile strength](https://en.wikipedia.org/wiki/Ultimate_tensile_strength). Tensile strength is the ability of a material to resist being pulled apart. Tensile strength for a material is often presented with compressive strength which is the ability of a material to resist being crushed together. Stone has excellent compressive strength which is why you can make buildings out of big stacks of it. Stone has weak tensile strength - inferior even to wood - which is why we never see stone in applications relying on tensile strength. In the tables below you will see that metals (except lead!) have tensile strength an order of magnitude greater than stones.
(Below screenshot from <http://www.arcraftplasma.com/welding/weldingdata/metalchar.htm>)
[](https://i.stack.imgur.com/bCvdi.gif)
(Below screenshot from [Stone: Building Stone, Rock Fill and Armourstone in Construction](https://books.google.com/books?id=Xcuoyxo33nsC&pg=PA467&lpg=PA467&dq=tensile+strength+stone&source=bl&ots=TVPuRYX5Fh&sig=lvvA-n0aNvBqRfB5zTwDSUiGlEA&hl=en&sa=X&ved=0ahUKEwivlPyMh97TAhVqxFQKHSJ8B7EQ6AEIMzAD#v=onepage&q=tensile%20strength%20stone&f=false))
[](https://i.stack.imgur.com/DaGqN.png)
The units for strength are actually the same: $$1\ meganewton/m^2\ (MN/m^2)\ =\ 1\ megapascal\ (MPa)$$
Of course, there is more to it than that: the article from the NY Times mentions that the softness of bronze makes it hard to maintain rifling in the cannon bore. I recently read [The New Science of Strong Materials: Or Why You Don't Fall Through the Floor](https://www.alibris.com/booksearch?mtype=B&qwork=4658240) which was really excellent and well written, covering materials science of exactly this sort. I recommend it for bedtime reading.
I have wondered if there might be a workaround for the stone cannon problem. The thing about a cannon is that if it fails on firing it might blow up and hurt its crew. A fix for this would be to bury it - the earth around it would contain a failure and provide a countering compressive force from the outside. Such a cannon could not be moved laterally and so could only be aimed by altering the explosive charge or weight of the ball - which is worth something.
If you were going to use packed earth to oppose the expansion of the barrel, maybe you could use wooden cannons, manufactured like a barrel. There would be some built in give. The staves would be a lot lighter and more durable than a stone tube. A technology inadequate to cast cannons could probably make barrels. There would, of course, be no rifling or anything like that. But a cannon of this sort would be adequate to heave a bomb over to the enemy.
Wikipedia has an entry on [wooden cannons](https://en.wikipedia.org/wiki/Wooden_cannon). I am loving this rope wrapped one. I have never read anything about burying the cannon or using packed earth with a nonmetal cannon.
[](https://i.stack.imgur.com/gMyrG.jpg)
[Answer]
>
> *Would it actually fire?*
>
>
>
Yes, at least once. You might want to retreat to a safe distance for the test firing.
>
> *Would it still be usable after firing?*
>
>
>
Depends if you calculated the right powder charge and if the flaws in the stone aren't too great.
>
> *Would it be as effective as a metal cannon?*
>
>
>
No. Compared to traditional metals for making cannons like brass, bronze, iron, and steel, stone has poor tensile strength (resistance to stretching), poor yield strength (how far it can stretch before it will not return to its original shape), and it's brittle (it will crack and shatter rather than stretch).
In addition, it's highly unlikely that a stone cannon can be rifled or retain it. It will be smoothbore and that means an unstabilized shell will be inaccurate. Its low velocity will further reduce the accuracy; the higher arcing trajectory means range finding will be very important.
>
> *How thick would the walls of the cannon have to be?*
>
>
>
Hard to tell. Unlike metal melted, cooled, and hammered into (ideally) a consistent state; stone has natural fissures, cracks, and flaws which will be weak points. Many will be invisible to the naked eye making it difficult to judge how thick a given cannon from a given piece of stone needs to be. These tiny cracks and fissures will open a little bit more every time the cannon is fired until it finally bursts.
And it depends on what you want to do with it. There are basically two uses for a cannon: as a kinetic weapon or as a delivery system for something else.
# Kinetic Weapon?
A kinetic weapon just means it does its damage by smacking into the target: a bullet or solid cannonball are kinetic weapons. It transfers its kinetic energy to the target. While the shape of the projectile has an effect, a longer, pointer projectile will fly and penetrate better, ultimately it's the kinetic energy that matters.
The problem for a stone cannon hoping to knock down a wall with solid shot is this:
$$energy\_{kinetic} = \frac12 mass \times velocity^2$$
What that says is doubling the weight of the projectile will double kinetic energy, but doubling the velocity will quadruple to kinetic energy! Similarly, halving the velocity will drop the energy to a quarter of what it was.
Firing a heavier shell is not as effective as firing a faster shell. Since your stone cannon cannot withstand the high pressures necessary for high velocity, its projectile will be very slow. It cannot fully make up for this with heavier shot: eventually, the shell becomes too big to handle. This is why, for example, tank cannons with the same caliber have wildly different effectiveness. The short [75mm M3 gun](https://en.wikipedia.org/wiki/75_mm_Gun_M2/M3/M6#M3) used on the M4 Sherman tank had a much lower velocity, and less ability to penetrate armor, than the guns of the same caliber like the long [76mm M1 gun](https://en.wikipedia.org/wiki/76_mm_gun_M1) on some later Shermans or the [75mm KwK 42](https://en.wikipedia.org/wiki/7.5_cm_KwK_42) on the Panther.
Your stone cannon can never make up for its very low pressure and low velocity compared to a metal cannon. It wouldn't make a good kinetic weapon. Firing stone balls with a stone cannon against a stone wall will make a big bang, but probably won't do much damage.
# A Delivery System For Something Else
The other way cannons are used is as a delivery system for something else. This is typically some sort of explosive, but it can also be chemical, biological, or even psychological (like leaflets). This is ideal for low-pressure guns because all you have to do is get the payload to the target. You could walk the projectile over to the target and set it off and it would work just as well.
The low velocity means if you want it to get very far you have to fire at a high angle. So you'll have some sort of stone howitzer or mortar firing an explosive shell.
[](https://i.stack.imgur.com/gE4jC.jpg)
[Source](https://en.wikipedia.org/wiki/Siege_artillery_in_the_American_Civil_War#/media/File:GunMortarTrajectory.jpg)
Since it will be large and heavy, this is ideally a siege weapon. Something you set up out of range of the enemy's artillery and isn't going to move around much. To give you an idea of a scale, here's a 13" mortar from the American Civil War.
[](https://i.stack.imgur.com/apwC9.jpg)
[Source](https://en.wikipedia.org/wiki/Siege_artillery_in_the_American_Civil_War#/media/File:Yorktown13inmortars1862.jpg)
That's probably made of iron or low quality steel. It weighed 17,000 lbs and fired a 200 lb shell. A stone cannon would be much, much larger.
This could be mitigated somewhat by reinforcing the stone cannon. Metal bands are normally wrapped around the chamber for reinforcement. A siege mortar, once in position, could be packed with additional stone and earth to further reinforce it... though with the very limited flexibility of stone it might do nothing more than providing a pit to contain the shrapnel when it bursts.
# Wooden Mortars
If you're looking for a non-metal to make your cannon out of, what is known to work is wood.
[Mythbusters famously made a wooden cannon work, wrapped with iron](https://www.youtube.com/watch?v=AJgYtt99V5s). More convincing is the use of wooden mortars by the [Union Army of the Tennessee](https://en.wikipedia.org/wiki/Army_of_the_Tennessee). Lacking proper siege weapons, they improvised. Reportedly these worked and could fire six to twelve pound shells, equivalent to [57mm](https://en.wikipedia.org/wiki/Ordnance_QF_6-pounder) and [76mm](https://en.wikipedia.org/wiki/QF_12_pounder_18_cwt_naval_gun) today. Very, very small for artillery that normally starts at 76mm up.
Again, it will be much lower velocity than a metal cannon, and it will be smoothbore. But it's much easier to bore out, and the flexibility of wood means reinforcing it with metal bands and earth will be more effective.
For more on wooden mortars and improvised siege weapons, try [Engineering Victory: The Union Siege of Vicksburg by Justin S. Solonick](https://muse.jhu.edu/article/617025/summary).
[Answer]
**There are multiple, historical examples of artillery/mortars firing stone balls.** Wikipedia has an entry (with photos, including some stone balls) showing only the biggest ones. So there's enough of a historical record that these weren't total death traps for the crews working them. I suspect there were many more of smaller caliber:
<https://en.wikipedia.org/wiki/List_of_the_largest_cannon_by_caliber#Stone_balls>
---
**If you are willing to accept the speculative, a stone cannon is possible -- without being carved from an existing block of stone. Instead, it could be made from two kinds of molten stone.** Probably re-melted stone, rather than lava, since we need two different types, one to produce strong, elastic fibers and a second (with a lower melting point) to form the matrix that the tensile fibers are embedded into, as follows.
**Basalt fibers are a real, usefully strong, commercially available thing.** See
[en.wikipedia.org/wiki/Basalt\_fiber](http://en.wikipedia.org/wiki/Basalt_fiber)
and
[basalt-fiber.com](http://basalt-fiber.com)
So, one could easily imagine using basalt fibers, in some suitable matrix, to make a cannon barrel out of stone. We first produce basalt fibers, which have yield stresses and strains very similar to glass fibers.
Some of the mechanical and thermal properties are summarized here:
<http://smarter-building-systems.com/smarter-building-basalt-faqs/>
I posit that an all-stone-derived fiber-reinforced ceramic material would give us much of the strength of the fibers, so long as we:
* make the fibers dominate the volume. Namely get as close to (pi/4 as optimal long cylinder packing, aligned case of course) as we can.
* embed the fibers in another melted mineral, so long as it has a lower melting temperature than the basalt and is chemically compatible at least short term. From
<http://www.minsocam.org/msa/collectors_corner/arc/tempmagmas.htm>
it's evident that we could use a rhyolitic mineral for the matrix material, for the lower melting temperature. There are alternatives, and
Cryolite (Na3AlF6) has a fairly low melting point:
<http://www.gly.uga.edu/railsback/Fundamentals/HardnessMeltingPlot06.pdf>
* The fiber is wound on a removable (or sacrificial) mandrel. The orientation of the fibers can be changed (even on a layer by layer basis) to optimize the strength and shock/fracture toughness.
* The wound fiber is placed in a mold (ideally a sealed, evacuated mold), preferably preheated, and then the molten-rock matrix is poured in.
* After the casting cools, the bore can be ground out to the desired diameter. With sufficiently localized heating (and a sufficiently large caliber to permit access), such a gun barrel could be repaired and maintained.
By judicious casting, a rifled barrel is not entirely beyond possibility.
This would only make sense if virtually no usable metal were available -- but such a world might exist.
[Answer]
Stone cannon balls were used many times. But not cannon for many reasons, not least of which would be cost. They're just impractical for a robust weapon. Of you made one thick enough to handle blasts and greased it every time it might work for a while, but would be hard to transport. If you used a rock in situ it would crack itself to pieces with repeated recoils.
There is a picture [here](http://www.laurelleaffarm.com/item-pages/0s-vintage-Italian-wine-decanter-Florentine-hand-painted-ceramic-cannon-stand-bottle-Laurel-Leaf-Farm-item-no-nt920199.htm) of a ceramic cannon but it probably hasn't been used in warfare although may have been around in a few arguments and strong words depending what it was loaded with.
[Answer]
There *is* a potential use for a stone cannon.
Stone, as mentioned previously, has very poor tensile strength, chips, and flakes, and has flaws which cannot be easily spotted. Unlike metal, melting it down to remove imperfections is not practical considering the extreme melting temperature of stone compared to metal. Stone cannot be worked as quickly or efficiently either. So, a cannon that is like a traditional metal (or even wood or bamboo) cannon is not worthwhile.
So forget about trying to make a conventional cannon.
A cannon contains the expanding gasses from a rapid burn of propellant such that it forces a projectile out the end of the barrel like a cork out of a champagne bottle. Stone isn't good at safely holding in these gasses in a reliable manner, so what if we invert the paradigm? Make the "cannon" and the projectile effectively the same thing.
Step 1; Create a carefully shaped hole in the ground. Pack the earth. It should be more or less crater shaped, but with a flat bottom and the entire "crater" should be angled as if from an impact at about 45 degrees.
Step 2: quickly grab a big boulder from nearby, shape the boulder roughly so that it has a very shallow "bowl" on one end. Knock off any really extreme points or ends so it is more or less round. You will also need a small groove or channel cut from one outside surface to the "bowl".
Step 3: Set a large charge of gunpowder or whatever you are using as propellant right in the middle of the flat bottom of your angled packed-earth crater. Lay flammable wick or fuse of some kind from the central mass straight out and up one side of the crater.
Step 4: Carefully lower boulder down over the charge so the charge is in the "bowl" you cut in the boulder and the wick falls inside the groove you cut earlier.
Step 5: Light the fuse, run a pretty good distance away.
Step 6: Watch a HUGE boulder go flying onto your enemy's fort or castle while a huge crater is formed in the ground. (At this point, you will want to have some beer out and be hooting and hollering).
Step 7: If the enemy continues to resist: rinse and repeat until they are tired of having several tons of rock come crashing down on them.
For this to be practical you need a civilization that has not perfected advanced metalworking but has been fooling around with explosives for a while. They have ready access to lots of manpower and are not afraid of engineering challenges. They also will set up and keep a siege of an enemy position for a long time if necessary. I imagine that if the Roman Empire had stuck around and had started tinkering with gunpowder a lot, this kind of thing might occur to them.
Technically, it's an "earth cannon" with a stone projectile, but since the stone is actually keeping the charge compressed, it's a debatable point.
Some advantages;
Unlike some very early heavy siege cannons, you only need to carry the gunpowder and some shovels and stone working tools, you don't need to drag 50 tons of bronze or iron cannon with you to the enemy castle. Depending on geography, you should be able to find suitable boulders close to whatever you are attacking. Earth is obviously always available.
Even if the boulder breaks up, it will probably be flying in more or less the correct direction. A scattershot of boulder hunks will still be very bad for the enemy.
[Answer]
# How many shots you want to fire?
One? not a too big problem. More? Umm, do you like Russian Roulette?
There was a not so historically accurate story about Tihany's (Tihany is located in Hungary) wooden cannon. *TL; Dr: It fired the ball, the cannon got destroyed, but it fired the cannonball.*
[](https://i.stack.imgur.com/ic49Cm.jpg)
# The problem:
**STONE IS BRITTLE** The problem is not with hardness, but with brittleness, less brittle materials deform gradually, brittle materials break.
# My proposed solution
* I can't say too much, but I'd go with [Tuffs](https://en.wikipedia.org/wiki/Tuff), they can seal heat
well, cheap, abundant, light, and soft.
* You can also consider using harder materials, which's recoil could be
lessened by a tuff casing.
But again, you'd better ask the others as I'm not 100 percent sure about these.
[Answer]
The big question here is: **"Would it still be usable after firing?"**
And the answer to that most likely is no.
Stone, as a molecule has a crystalline structure like glass and sand. Glass can be really strong, like stone but it will always be **brittle** meaning it can't resist vibrations.
Some glass (and stone, concrete, etc.) can hold-up tremendous force without breaking, it can withstand a lot of pressure, but impulse is a different kind of force, **impulse is the force that a cannon must withstand**
[](https://i.stack.imgur.com/LyESd.jpg)
The tool shown here is a hammer drill, it works by providing a great impulsive force through hard vibrations that will **tear through stone or concrete** with ease, however, this tool would never in a million years tear through iron or steel.
In summary, a stone cannon would look great and it would work for a few shots, but once the pieces start chipping away, it is going to fall apart.
Final note: This is true for all stones and crystalline structures, even diamond! A diamond cannon would also have the same problem, just because it can't be scratched doesn't mean it can't be shattered.
[Answer]
You might have better luck with a dirt/stone cannon. the main problem with the stone is how brittle it is. this would lead it to shatter after only a few shots if that. if you packed the inside of your stone cannon with a very compact layer of dirt, or other dense padding, you might be able to re-use the cannon by refilling the cushion after every shot. the only downside is that you sacrifice a good deal of the force to do this, so your cannon will really only be effective against infantry, not fortifications.
] |
[Question]
[
Lord Woodesy wants to have a *glorious* antlered helm! But he has heard that having antlers, horns, or other projections on a helmet can be severely detrimental in conflict since they can be grabbed or violently twist the head if struck. But Lord Woodesey *really* wants that antlered helmet.
So he came up with an idea, what if he had his helmet smith attach antlers but leave them not so firmly connected so that a blow will break them off instead.
So my question is, would it be possible to make a helmet that has antlers (made of actual deer antlers, a young deer's) that are only loosely connected so that you can wear it into combat and generally "around"? It would also be nice to know if this would work with other things such as horns or metal structures.
[Answer]
Can Lord Woodesey have an antlered helm? Yep, you bet, absolutely. As Kilisi pointed out, lots of impractical/decorative armor existed back in the day, just because the wearers liked how it looked. Does Lord Woodesey *really* need it to be battle-worthy? Even if he does, allow me to point out that in a fantasy/RPG setting if you say "Lord Woodesey appeared, wearing a badass antlered helm", no one is going to say, "but are the antlers attached loosely enough to prevent brain damage?"
However, since you've asked, and it got my imagination firing, I came up with a few (uneducated) attempts at making "easy-break less-head-trauma" helmets. Many might be impractical if tested, but it was fun to dream. And even if none of my ideas would actually work, I have no doubt that it is possible to do what you are asking. A good engineer could probably solve the puzzle fairly quickly. Would it ever be quite as safe or efficient as a normal, practical helmet? Unlikely. You have freakin' horns sticking up off your head. So, with that out of the way, here are my best horn-hat catastrophes:
[](https://i.stack.imgur.com/ArtlH.jpg)
...or we could be boring and just glue it...
[Answer]
## Yes, absolutely
Lord Woodesey and I seem to have had the same idea, great minds think alike, so they say. There are several ways to have a deer antler helm without it being detrimental.
The easiest, and by far the simplest, idea is to fix the antlers to the helm and then cut through them near the base, leaving you with two nubs attached to the side of the helmet. Then, you glue the antlers back on to those nubs (glue did exist in Medieval times but you may also be able to use wax if you prefer).
This may seem redundant but, by cutting and gluing the antler, you have created a structural weakness. This means that, when force is applied from someone pulling it or a weapon strike, the antler breaks off where we glued it to the base. This prevents someone being able to use it against you but still allows for you to wear your antlers into battle. The plus side of this is you may also be able to re-glue the antler back on after the battle if you pick it up and its not too damaged. A similar thing can also be done with horns, using the exact same process as described above.
Metal though is a little bit different. Due to its weight, it would be a lot harder to use glue to achieve the same effect with steel or bronze, possible with modern glues but less so with Medieval ones. Instead, what we can do is make these pieces out of a lighter material such as aluminium or tin and weld the pieces together. This means they do not add too much extra weight, can be broken off easily due to the structural weakness and can possibly be repaired or replaced after the fight.
**Alternatively**
Rather than risk Lord Woodesey damaging the antlers (or whatever else he chooses to decorate his helmet with), we can instead have detachable horns. Essentially we can have something similar to arrow or spear heads. A metal fixture goes onto the side of the helmet and the antler or horn is pushed into that fixture (it has already been filed down to make sure it is the right size and a snug fit).
This way your antlers can easily be pulled out of their fixtures before battle, so they are not a hinderance, and put back in when not in combat. This also prevents them from being damaged or lost in a fight. You could even do a similar thing with metal.
[Answer]
You could do it easily, it still won't be as effective as an unadorned helmet, and I don't see the need to wear it in an actual battle.
There was lots of ornamental armour around back in the day, and the Japanese Samurai armour had all sorts of projections on helmets. So it's not a showstopper. The projections were thin soft metals that would crumple or get chopped off if hit. So something as simple as attaching the antlers to a thin soft metal holder would do the job.
[Answer]
Kilisi was right to bring up the Samurai helmet, but missed the most important point: the adornments on Samurai helmets were not just ornamental. They were designed to work like a combination of sloped and ablative armor making it almost impossible for a weapon to strike a samurai's head without being mostly deflected or absorbed.
To further explain the 2 mechanics at play:
Sloped Armor: When you strike armor against a flat surface or inside of a crease, you have the best chance of penetrating it because all of your force goes into the armor, and you penetrate it in the shortest path through it. When you strike armor at an angle, a portion of your force ricochettes away from the target, plus the armor is "thicker" than going straight through it. So, while antlers might not be ideal here because there are so many creases to catch, there are various horn shapes such as the those of ampala, rams, or antelopes which will almost always create some degree of a ricochet when hit.
Ablative Armor: Armor designed to bend and shatter when hit will distribute an impact across the shatter zone instead of letting it focus into one spot. So, if for example, had a ram's horn on the side of your helmet, and a battle axe hit it, part of the axe's energy would go into the impact, and some would go through the impact to hit your actual helmet. By decelerating the impact over several inches and distributing it across the shattering horn, the strike will be far less harmful than if the axe were to suddenly impact the side of your helmet.
So, instead of worrying about how to make antlers fall off as a whole, I'd try to make them ablate impact as best as possible. To do this, I would drill holes at the creases so, that it shatters at a point before driving too much force down into his neck, but giving enough resistance to slow the weapon that hit it.
[Answer]
It depends.
The antlers can be attached to the helmet, so that it takes a certain amount of force to break them off. The exact amount of force can be chosen for your needs.
The amount of force to break them needs to be high enough that they don't break off by accident. Google says deer antlers might be 1.3kg (3 pounds), and might be 60cm (2 feet) (not the same ones antlers, just for an idea of scale).
If his lordship were to turn his head quickly (especially in the middle of battle), that would apply a fair amount of force to the base of the antlers. Obviously, it would need to withstand that, without breaking. If an attacker were to apply exactly this amount of force to the antlers, the helmet would transfer to his lordship.
The antlers themselves can withstand the deer (or moose, or whatever), so that's not a problem.
[Answer]
If they are not used for actual headbutting, and depending on the weapons technology, this may not matter. With guns, muskets, spears, bows and arrows, swords, etc, the chances of an attacker getting close enough to grab the antlers would be very unlikely. Especially if Lord Woodsey is on horseback.
In wrestling, of course, it's a different matter.
I would tend to modified antlers - if you can embed something sharp into the surface (think glass shards, razor wire), then anyone grabbing the antlers with bare hands will come off second best.
[Answer]
I would say, it depends on the actual conditions of the battlefield. Do people fight on foot or in horseback in this setting. What is the average length of a typical sword.
If we assume bronze to really iron age, with big shields and short stabbing swords, an antlered helmet is viable, especially as it would be as much ritual as functional.
If the conditions are similar to the high middle ages, and Lord Woodesy is a knight on a horseback with a lance, he can have antlered helmet as a fancy - he most likely would not be hit from above, and against the other lance the form of the visor of his helmet is more important. Jousting helmets if high middle ages often had different decorations, including horns.
In most other cases antlers would make sense only if they are easy to snap of the helmet. I do not think there was any glue strong enough to hold horn to metal before advanced chemistry. I would try using brass or wood pins to hold them instead.
[Answer]
Yes. The answer is in the fins. FCS II surf fins. Check it out. <https://www.surffcs.com/pages/fin-systems>
Firm, works side to side. Upon impact, they release. Sounds exactly what you want.
[Answer]
**Want to improve this post?** Provide detailed answers to this question, including citations and an explanation of why your answer is correct. Answers without enough detail may be edited or deleted.
Lord Woodesy wears his helm as testament to his superiority. He can fight with a ludicrous adornment and inspire his followers. He has developed a fighting technique to deal with this.
] |
[Question]
[
## Why this question is different from existing questions...
The closest question to mine is [Anatomically Correct Cerberus](https://worldbuilding.stackexchange.com/questions/51758/anatomically-correct-cerberus). It is clear from the answers to that question and indeed it's axiomatic to the scientific community at large that polycephaly is not a particularly useful trait in **OUR** world. Therein lies the distinction -- in my post, I explicitly concede that point. My question is different because I'm flipping the script. Polycephaly is a losing proposition here on Earth, so let's envision an alien world where polycephaly makes sense.
In the Anatomically Correct Cerberus post, Green said: "I can't think of a set of circumstances where it's a clear and long-standing advantage to have three heads instead of just one." He has a point, it's a challenge. I read through a lot of material, and I just have some modest ideas. Still, just because *some* of us cannot think of the circumstances doesn't mean that *none* of us can.
I mean it's easy to say "it's just impossible, case closed." However, the most fascinating part of the topic (to me at least) is unresolved. Namely, thinking of a world with the circumstances to allow for polycephaly to occur is unresolved. That's why I think it's worth taking a deeper look. I would like to keep the use of faerie dust to a minimum (hence the science-based tags), but if it's a bit of a tall order for people, I can allow certain latitudes where necessary to generate useful and creative discussion.
## Polycephaly
### Premise
Having multiple heads, or [Polycephaly](https://en.wikipedia.org/wiki/Polycephaly) is a very visually stirring trait that we often find in mythological creatures. Chimera and Cerberus are two such examples.
[](https://i.stack.imgur.com/tSWug.png)
Conventionally, the polycephalous trait tends not to be favored by natural selection. It is a trait that is often very rare and even when it is observed, the organism is thought to be handicapped by the trait. Consider the following comments regarding a two-headed snake:
*"Just watching them feed, often fighting over which head will swallow the prey, shows that feeding takes a good deal of time, during which they would be highly vulnerable to predators. They also have a great deal of difficulty deciding which direction to go, and if they had to respond to an attack quickly they would just not be capable of it." -- [National Geographic](https://news.nationalgeographic.com/news/2002/03/0318_0319_twoheadsnake.html)*
As I researched the concept, I became more acutely aware of the evolutionary challenges that would inhibit the existence of a polycephalous creature. In terms of evolution, having one brain is an expensive component -- let alone several. The energy resources that would be required would pose a challenge for the organism to be able to thrive and reproduce. However, just because polycephalous creatures do not fare well in our world, does not mean that there couldn't be a fictional world in which polycephaly would be an advantageous trait and thus favored by natural selection.
### Question
I would now like to open the floor to answers that can address the following question: What kind of world could have the conditions that would be conducive to the emergence (and perhaps dominance) of a polycephalous creature?
### Further Clarification
* a herbivorous or carnivorous creature is acceptable
* all biomes are fair game (tropical, tundra, desert, etc)
* the ecosystem is a complex variable and for the sake of simplicity you
may assume other ecosystem constituents as necessary, just make sure
you have a small list of assumptions for clarity
* (optional) Ideally, I would like to keep the scope as is, but to
avert undue subjectivity or being too broad, if you so desire, you
may limit the scope of the question to our buddy Cerberus (pictured
above)
[Answer]
The heads are not identical. Each is specialized through **adaptive radiation** like [Darwin's finches](https://en.wikipedia.org/wiki/Darwin%27s_finches).
[](https://i.stack.imgur.com/QuJrT.jpg)
The heads may not be limited to types of food, but for any reason heads evolve: to set a pair of eyes further apart and higher, another head for hunting underwater, maybe one head just to attract a mate (that one wouldn't need to eat or think, just look attractive), and another head for communicating.
At birth the heads might not be differentiated.
[](https://i.stack.imgur.com/9vkQP.jpg)
Lobsters are born with matching claws, but as they grow older one becomes dominant and they develop into two completely different claws called a pincher and a crusher. The heads on your creature might be similar with one head naturally becoming dominant, and the lessor heads developing for secondary tasks (whatever they may be).
[Answer]
# They have false heads
Some species today have evolved false heads in order to protect their real heads from predators. some examples include: Thorny Devil or Long-banded Silverline
[](https://i.stack.imgur.com/7RiTWm.jpg) [](https://i.stack.imgur.com/BPHnim.jpg)
Over time, your species could have evolved to have more sophisticated 'false heads' that look more and more like a real head. They may even evolve to have sensory organs, or be able to move like a real head.
[Answer]
Your environment could be extremely hostile to smaller creatures, resulting in various strategies to become large. You'll have a lot of creatures which have many offspring which grow extremely rapidly in the hopes that some survive, but other options are available.
Your multi-headed species engages in a type of symbiosis, where its offspring develop on its body with a shared circulatory and nervous system. It would have multiple heads which could watch in several directions alerting it to potential threats. It will always have a range of head sizes from a single large one ranging down to tiny developing heads. The larger heads would act more independently, trying to eat their own food and potentially disagreeing with the others. As a head reaches maturity it would develop a longer more muscular neck (actually the rest of its body developing) before gaining legs and separating from its parent. A newly separated creature would only have one head for a time before it developed offspring of its own.
[Answer]
Not particularly knowledgeable on the subject, but octopi came to mind. They do not have multiple heads, but their tentacles have neural clusters that essentially make them able to act and think, relatively, independently - in a sense, they can act as 8 creatures, or coordinate into 1. Coupled with their sensory input from their legs (not eyes, but octopi move a lot by touch) one can make a parallel with a head (eyes - sensors, brain - neural cluster). Especially if the creature you're thinking of designing actually has their main cognitive tool somewhere else, and the heads act more like semi independent extensions to allow multitasking.
Possible uses: Eyes in the back of your head, near perfect echolocation, multiple limb coordination (which would require a shit-ton of motor neurons), redundancy (an environment which you are pretty likely to damage your head, literally).
Just note that having multiple brains is expensive. Which might mean that food is abundant for this animal but, maybe, this animal itself is a food for multiple predators (so energy efficiency is less relevant than perception / defense capabilities).
[Answer]
The various negatives related to polycephaly are primarily because of multiple conflicting directives issued by two brains sharing a single body. Place a single brain elsewhere in the body, say protected by a bony hump in the central torso, and you can have two or more heads without conflict.
Which is basically how you get the [Pierson's Puppeteers](https://en.wikipedia.org/wiki/Pierson%27s_Puppeteers).
From an evolutionary perspective multiple heads would seem to be a contra-survival trait. Niven worked around this for the puppeteers by framing it as a defensive advantage that allowed a herbivore to better triangulate lethal kicks against a predator that was following it. This was so extremely advantageous in the primitive setting of the Puppeteer home world that they became the dominant life form.
Another thing to overcome here is that sensory data like sight and hearing needs to be processed extremely quickly and so needs the shortest possible path to the relevant sections of the brain. Having your eyes on the ends of tentacles with several feet of nerves leading to the brain would be extremely inefficient and almost certainly an evolutionary disadvantage. The solution in this case might be to have a distributed nervous system instead of a central nervous system. Have processing for the visual inputs happen in the neural network of the head with data fed out from there to the 'brain' elements in the rest of the body. Of course there are many potential downsides to having a distributed nervous system as well, but let's ignore them for now.
The final option I have for you is an environment which lacks suitable evolutionary selection pressure to select against the disadvantageous multiple-brain scenario. Given that two brains cooperating together on a single problem may in fact produce more effective solutions, and that cooperative brains would ultimately be more successful than uncooperative, a mutation that produced polycephalic offspring could in fact result in a polycephalic species. The environment would have to be quite benign compared to our own with minimal predation and so on to allow the initial few generations to survive long enough for the species to find its own survival specialization.
[Answer]
What about one head being diurnal, another nocturnal and another cathemeral?
While the nocturnal and diurnal heads take long turns, the cathemeral head would be active during important parts of the day, such as when hunting for food or finding shelter.
Each head could in turn wake the other when in a panic (a sudden flush of adrenaline would do that for most creatures anyway) and then all three could be active, but only rarely.
Couple this with extra features, such as different sensory organs (say the diurnal head focuses on eyes whilst the nocturnal head focuses on its nose) the three could work together even while they are all awake.
I imagine this could come from pressure to be awake constantly. Perhaps a dire shortage of food requiring constant travel, or constant predation. A polycephal creature would probably be a large creature to support the heads, so perhaps its natural predators are small and pack-hunters, meaning awareness and the ability to escape early pushed the need to keep so many heads?
---
Alternatively use a head like a hand!
I believe a key point that makes polycephaly a problem is that each head attempts to act independently. Solving this by including a sort of **ultimate brain** located in the middle of the others, with the heads having **smaller brains** or perhaps even **giant nerve centres** as opposed to brains, may make more sense.
Essentially, take the brain out of the head and stick it in the chest, then control each head together. This would require a complex brain (good thing it has so much space in there!) to be able to comprehend so many senses (three sets of independently moving eyes, ears and noses is a bit much!).
[Answer]
The creature could reproduce by budding. Either Sexually or Asexually. Instead of growing their young in an egg or a womb, they simply grow out of their parents.
[Answer]
This is not applicable for a wide range of two-headed creatures because I can't imagine this as an ultimate survivor strategy but there was mention of tool use in finches in another answer, so technically, having two heads with a long neck and a type of mouth or beak that can grip well could be a substitute of having two arms with opposable thumbs. (In a creature that is unable to use its limbs in a similar way because they were just not designed for it or are in the long place/height.) I.e. make the species capable of advanced tool use.
For this to become a trait, a lot of favourable conditions need to be in place 1) to introduce this as a trait and not just a one-time coincidence of birth and 2) a safe environment for the new species in that awkward phase when they haven't yet worked out how to use the new trait well enough to compensate for its drawbacks and turn it into a net benefit.
[Answer]
**What constitutes a head?**
In alien and otherworldly anatomy the answer may be very different than that which is familiar to us.
The head and neck arrangement as we know it has always seemed to me somewhat maladaptive. With the brain, eyes, ears, nose and mouth all in the head any injury to it is catastrophic. A broken neck or a ruptured trachea or carotid artery are all quickly fatal for a wild animal and easily sustained. The whole assembly could be considered a single point of failure.
So it doesn't seem unreasonable that in a rerun of evolution a different body plan might win out. Perhaps a creature might have a head for eating that can double as a backup respiratory tract, but isn't intimately entwined. A head each for two (or more) eyes as a protection against blindness. They could even have localised visual cortices.
Does it even make sense to have the brain perched up there? Maybe it should be in the centre of the body. Then having multiple heads has no significant impact on neurology.
I think considering the disadvantages of single headed anatomy could help you find a lot of ideas. I hope this small selection helps.
\*\* Ecology \*\*
To put this in an ecological context imagine a savannah watering hole. All manner of creatures must visit it for hydration and many would be at each other's throats, if they have them.
In the real world a drinking animal must lower its entire head to drink, which places its eyes just above the water level. A low bush could conceal a predator.
But if the animal has its mouth on a dedicated extremity then it may lower this to the water while its eyes remain high, granting greater visibility. This is arguably an advantage enjoyed by elephants who use their trunks to transport water to their mouths; a nice precedent.
The eyes could each stand alone, or even four eyes in pairs for all around binocular vision. With its mouth in the water but eyes and nose in the air, the animal would be much harder to sneak up on.
But if this anatomy is established early in evolutionary history then predators could also benefit. Imagine a muscular neck and jaws with sharp teeth buried, vulture like, in a carcass while elevated elevated eyes remain alert to opportunists or its own predators. Out could much more readily turn that powerful maw upon a foe.
High above, fruit eating avian creatures have only eyes in their head. A large brain sits at their centre of mass and a mouth between the shoulders, ready to snap up berries when, perched, the creature uses its over developed eyelids to pick them.
[Answer]
## It IS possible but exceedingly IMPROBABLE
As a **thought** experiment how would these 3 heads on one organism evolve under the current rules of our world (but with fantastic circumstances)? In order to evolve multiple heads in the current science you really only have 3 possible (general) scenarios.
1. The creature evolved a head then was slowly favored to grow a second head from scratch via selection, and so on. This means that the heads are not the same as they have evolved independently. They won't have the same kinds, size, type, function, etc of brain, or face, or anything. This would be more similar to a a creature with a sheep head and a dog head, no 2 or 3 dog heads.
2. Somehow a creature mutated and was born with 2 heads right away and this was selected by the environment to persist. Having a complex system like a head and brain just randomly be duplicated is probably so unlikely as to again be considered just impossible.
\*
The only reasonable way this might happen is if you have a fetal abnormality that results in a chimera of 2-3 different organisms fused together. But again for the sake of reproduction we have a problem; only 1 of them will be able to reproduce because an egg cell only accepts one sperm cell. So offspring will be the child of only one of these chimera heads.
The mutation of chimeraism would have to be favored in general (even when it doesn't results in a fused chimera), and then fused chimeras would have to somehow out perform the same number of organisms as independent individual creatures for this crazy fluke of a mutation to persist at all.
3. The creature somehow evolved 2-3 independent brains right from the start. Developing brains is costly so developing 3 similar or identical brains is extremely unlikely if alternatives (and there are many better ones) exists. 3 real heads with each its own brain... I can only think of sexual selection pushing this forward (like the peacock feathers) because it is otherwise so useless.
4. Finally the best option, the heads are not real heads but are appendages. So in this case the animal would probably have something more like a centralized brain and the heads would just be another kind of appendage (like arms/tentacles), but shaped as heads and with some of the same functionality like being able to see and being an entrance for food. This is the most reasonable but is obviously a redefinition of the term 3 heads.
So if life follows the general rules ours follows; evolution takes place over a long time, where the best at surviving and reproducing are best represented, there is almost no scenario in which multiple heads in its literal sense would evolve.
To have multiple heads be a plausible evolutionary path in their full capacity (3 identical heads and brains) you have to throw out life as we know it. For example maybe a planet where life evolves in seconds rather years, or the method of selection is NOT survival and NOT reproduction.
Either way 3 heads is a fringe case even in the multiverse.
---
## Expanding on why this would probably never happen anywhere:
As a biologist I would say that a plausible scenario in which natural selection would favor evolving multiple heads is probably so improbable as to be impossible in any form of life or biology that resembles our own (even in wildly alien environments). I will put to you first the argument about why this adaption is improbable in our current universe no matter where you are.
The reason this won't plausibly happen is because of the way evolution takes place which sets up basic constraints for the population. Some seemingly unnecessary things can evolve if they have a big payoff (like peacock feathers and reproduction), but multiple heads combines some of the biggest no no's in all of evolutionary science and this adaption has to somehow be better than the alternatives to evolve (there were no simpler or better adaptions that could have taken place?).
The problems in general are:
I) Having an extremely costly AND unnecessary feature. The problem here is that the brain is the most developmentally expensive part of an organism which will negatively impact not just its early development but its entire life by requiring constantly more resources to exist thereby reducing its survivability, chances of making it to adulthood, making it out of the womb, everything. This is true in any environment. So unless there is a massive pay off at the end there will actively be selection towards removing these heads if they ever came to exist.
II) Evolving 3 extremely complex systems is not parsimonious, nor is somehow maintaining all of them. If anything can do the same job but with fewer steps to get there or cheaper, that's probably what happened instead.
III) The heavy resource requirement accrued means the benefits have to be extreme which means the organism cannot adapt well to changes. This means it probably didn't survive environmental changes that reduced food or any of the huge list of things it needed to survive to adulthood. This also means the 3 headed creature didn't exist long enough to develop 3 fully functional heads in the first place.
IV) Many more reasons I unfortunately can't remember right now as I am rusty.
So the environment doesn't matter so much as the basic contraints of selection. So to realistically make this possible anywhere, the basic principles of life or evolution have to be different. If they are different, they are beyond our current human comprehension. That is the best answer.
*If you want to use one of the above examples, you will want some place doused with radiation where the females for some reason LOVE the multi-headed males A LOT.*
In our universe however, if you ever really wanted to have these things around, a mad scientist or crazy government organization would probably be your best bet.
[Answer]
Conjoined twins can have multiple heads, so this isn't necessarily an issue on the same scale as trying to evolve wheels.
What you need is an environment where conjoined births are frequent, and a propensity to conjoined pregnancy is inherited, but the problems faced by conjoined twins on this planet (e.g. inability to coordinate movement effectively enough) aren't enough of an evolutionary disadvantage to matter.
Perhaps a degree of telepathy that means the twins can actually run at a sprint from an early age, and a need for 24 hour vigilance from some apex predator would be sufficient for the species to survive long enough. Those unlucky enough to be born without a twin get eaten the first time they sleep away from home, so only the conjoined twins survive until adulthood?
Not exactly what you were asking for, but is it close enough?
[Answer]
I'll go on a different tack: One day, the release of a toxic bacterial colony (from an evil scientist's lab, no doubt) kills many in the community, but 10 pregnant females survive. of these, 6 give birth to two-headed children (either a straight double head, or a Siamese Twin with a single body and a semi-separated neck). As luck (i.e. evolution) would have it, the expressed genes for this bicephaly are next to the genes for immunity from this toxic bacteria. Within a few generations, only bicephalics survive.
[Answer]
Lets start with the Octopus. As has been mentioned, it has neural clusters in it's tentacles that let them operate independently. Then we have a long necked creature that sends its head in to directly eat the prey instead of relying on suction cups to pull the prey out.
One drawback is that while its head is neck deep into a crevasse, it cannot see predators sneaking up on it. So, a mutation with an extra undeveloped head would be good for keeping watch and biting attackers while it extracts its main head.
This only becomes really useful if the two brains communicate. Otherwise, mini head wants to run away while feeding head is twisted around in the crevasse, anchoring it in position. So, mini head slowly becomes more dominant (not being eaten has more survival value than eating).
Another mutation leads to another eating head. Twice the chance of getting food. This requires more coordination. The neural cluster that coordinates activity between the heads gets more complex. Eventually, most "thinking" happens in the neural cluster that connects everything.
Other heads may appear due to the same mutation until some optimal number if heads is achieved (which may be different for different species).
At this point, the "main head" may lose it's dominance to the central cluster that connects the heads.
In different species, the heads may specialize.
[Answer]
"Natural selection" and "evolution" are often used interchangeably, but in fact, these are two different concepts. Natural selection is actually a subsidiary process of evolution. Evolution deals with "what traits make it into the genome of a given species", whereas natural selection deals with "what traits REMAIN in the genome of a given species". If you don't particularly care how the polycephaly evolved in the first place (though barring weird science and/or some magical interference, depending upon your setting, the answer there is almost certainly "random mutation"), you only need to worry about the second question.
We already have examples from our world where many non-beneficial traits (or even actively negative ones) remain in the genome, because while people think of natural selection as the promotion of what works, it actually is much more commonly a reductive measure, meaning it provides for the elimination of that which does NOT work. Now, in our world, polycephaly is a pretty crippling disadvantage, usually. So for natural selection to favor your polycephalous species, polycephaly needs to either A) confer none of the penalties that it does in our world (or at least, not enough to make the individual organisms of this imaginary species unviable), or B) confer advantages that heavily outweigh them.
Off hand, I can think of only two circumstances that would promote this particular trait by means of natural selection, and they would probably need to exist in tandem for the trait not to be weeded out. First, energy conservation would need to be less of a worry for this creature (or for all creatures) in your world than in ours. Something like a creature capable of direct photosynthetic absorption of sunlight would be a good start.
Secondly, aside from the abundance of available energy, I would expect conditions in such a world to otherwise be exceptionally unfriendly to our life-form, such that the additional weaponry provided by extra jaws and/or extra sensory input and/or redundant neuro-sensory hardware was almost a necessary condition of survival. I realize that my answer here was more general, but hopefully it gives you some angles from which to start considering the problem.
[Answer]
Guard duty: At all times at least one head could be awake (while some of the other heads slept). Such a creature could never be surprised by a stronger predator, and never let a weaker prey tip-toe past it. On the other hand, saying how a trait *might* be advantageous says nothing if it could have actually evolved. An animal which rolls on wheels would have an advantage in locomotion, but there doesn't seem to be any plausible evolutionary pathway to it, hence it [never happened](https://biology.stackexchange.com/q/7932).
[Answer]
From the perspective of it being a prey animal, here are some ideas I had:
1) The most obvious pressures for more heads are more eyes to look with, and more mouths to feed. You wouldn't need complex brains for this task, most of these functions are ones that could be done without much conscious effort. Other commenters went in better detail about this if that's the route you're going for, but I'll add that an interesting twist to this is a regenerative ability with the multiple heads if they're simple enough; the main head could be the only one unable to regenerate.
2) Multiple heads could also be redundant 'back up' features for a particularly hardy animal. Redundant organs already exist in earth creatures, so obviously, that's something that has some evolutionary pressure, albeit not precisely like we're describing.
3) Another could be making the creature look more fierce with more apparent ways to defend itself (two or more sets of jaws or points of articulation to attack with). Pretty straightforward, although this is under the assumption that other polycephalous, successful predators with a common (multiheaded) ancestor to this animal would put pressure on it to retain its many heads. Also, keeping in mind that evolution favors energy conservation, an animal with many heads to attack should have reduced forelimbs or something in that regard (something that could also be used to attack other animals. It would not need both many heads and attacking limbs. The most realistic creature for this, ironically, is the snake, or something akin to a polycephalous theropod)
4) Lastly, what I find more realistic is the purpose of making the creature appear like there's more than one of it there at once, like a false group/herd. To add on to that latter point, it can have Zebra like markings (dazzle camouflage) to heighten the illusion further, and/or vibrant eyespots to spook wary predators or rivals when someone gets close enough for the initial illusion to waver. The heads could be largely nonfunctional or have a simple function. Totally up to you. It would be most effective to at least allow them a range of motion, like a tail.
I'll add pressures that a predator would need later when I think of some. I didn't intend to give an official answer to this! My comment was just too long c:
[Answer]
There are some problems, none is really unsolveable, but all together tend to restrict this:
1. One brain is more than enough, so a multiheaded species will probably not have its brain in its head (although [dinosaurs having two brains](https://www.smithsonianmag.com/science-nature/the-double-dinosaur-brain-myth-12155823/) is probably bullshit, a species COULD carry its brain somewhere else);
2. Having your brain separated from main sensory organs (e.g. eyes) tends to complicate things, but there are insects with stalk eyes and similar that solve this problem;
3. Having secondary digestive entrance is probably the worst problem; I don't really think there will ever be something that has more than one fully functional mouth attached to its "heads".
So don't make it have its mouth on the heads and brain contained in it - make it specialized limbs that come with eyes/ears/whatever and place the mouth somewhere on the main body.
That doesn't need those head/hands to not have teeth, or at least something like lobster claws to rip stuff apart instead of chewing.
[Answer]
Symbiotic relationships seem like the only way this could happen to me. Let's just take a dog as an example. You're a parasite or something else that requires another organism to do well to survive. Your dog in the fight gets rejected by the pack or attached. Ordinarily your dog would die, but your dog has you and you can help it fight. For some reason, you decide that the best way to help your dog fight is to grow an offensive head on it and literally fight the other dogs. Perhaps this is all your capable of. Perhaps this is just what you do. For some reason this actually works - maybe humans think your a god - and suddenly something else is living with you and your dog while giving it another head. This sounds pretty dumb, but there are parasites that eat fish tongues and then replace them. This defensive appendage parasite idea is far fetched, but plausible.
This also doesn't need to happen with a parasite. Maybe this creatures young just stay on it for a long time and simply look like other heads due to some physical features. Perhaps your creatures are just really weird furry scorpions.
Alternatively, a parasite could do something that forces this trait in its host. This wouldn't be an advantage to the host, but it would/could be a massive advantage to the parasite itself.
When it comes right down to it there aren't a lot of benefits to having two heads. It looks pretty cool and that's about it. There's honestly not a benefit that could be produced by having multiple heads that I can think of that couldn't be produced in a less troublesome fashion by just having part of a head.
[Answer]
*If* such a development happened, odds are the extra heads simply wouldn't last very long, evolutionarily speaking, as "heads". Consider the beastie in the image. If the extra heads are primarily used for sensory organs, then odds are they'd get pared down to, essentially, two extra arms/tentacles with the organs on the end (basically, the jaws and everything necessary for them disappear). If they're used primarily as weapons, manipulators, odds are they get reduced to two extra arms/tentacles with grasping claws on the end (everything except the jaws disappears).
[Answer]
Our brains are in our head because worm's sense cells were near the front and quick reaction to stimulus was helpful. You need an environment that forces a worm to have sense organs on its head and tail.
What if your first animals developed in a continuous stream of water with various speeds. Side to side movement to switch to a faster or slower flow would be preferred. Side appendages for this might make it difficult to "see" both forwards and backwards.
For these animals the front brain would "look" for food in slower moving flows while the hind brain would avoid predators approaching from behind in faster flows. They would both control movement but the hind brain would override the front brain.
After these animals leave the stream the two brain configuration should be preserved because being able to watch your own back is pretty helpful.
I think the reason we don't is because early animals found it easy to detect food and hard to detect predators. I think any environment where predator detection was easy for a 100 cell animal might create two brained animals.
] |
[Question]
[
Humanity has spread throughout the galaxy and has split into several factions in a galactic "cold war" type conflict. The two major factions (think USSR and USA) are in a galactic deadlock, with numerous smaller space-faring factions fighting small proxy wars.
Introduce the arrival of an alien race, (a lot of hand-waving here) and for one reason or another the aliens side with only one of the human factions. The aliens' superior tech turns the tide in the war.
My question is: What are some reasons why the aliens would side with one faction of humanity, as opposed to viewing humanity as a whole, wiping all humanity out, etc?
A couple things:
* The combined efforts of all humanity could beat the aliens
* For political reasons, the faction without the aliens cannot broker a truce/peace
* The aliens know human culture, languages, etc etc
[Answer]
Alliances always come down to each party needing something from the other.
The humans need help defeating their political enemies (other humans). The aliens must similarly need something which only humanity can provide.
For example, the aliens might themselves have powerful enemies to fight, and require soldiers to defend their wolds because there's simply not enough of them to win out. They might be willing to provide humanity with the the technology upgrades needed to defeat their enemies in return for support in their own conflict.
In this case they would choose to support the human faction whose morality and political inclinations most closely match their own, and whom they feel might be trusted to actually help them.
Another option might be that the aliens are looking for a new world to call home, and are willing to trade technology in exchange for a new planet to settle. This scenario is a little trickier because a race of advanced aliens should be able to locate a world to live on without help from mankind. You'd have to come up with various reasons why they are not able to do so (their ships are breaking down and they're on their last legs, or something of that nature).
[Answer]
* The combined efforts of all humanity could beat the aliens
There's your answer, right there. They help one faction, because a combined humanity is a threat to them, and a fractured humanity is not. Destroying either side of the conflict removes humanity as a threat, thus making the alien race safe. Likewise, keeping the conflict ongoing is going to keep them safer as well.
Considering the way humans generally respond to unknown and new things, the aliens would be wise to appear helpful (to one side) and remove the humans as a threat to themselves. Both human factions would certainly set aside their differences and destroy the aliens instead if they appeared to be any kind of threat to the human species. (And with humans, it doesn't take much to be perceived as a threat to the species.)
[Answer]
* The side that the aliens side with has something that they want.
This could be anything. From a way station, to a vacation spot, to a larger population of cannon fodder to fight their own war, to labor, and so on. For all we know, they side with the U.S. because the beaches are better. A petty reason, yes, but possible.
* This country, culturally, seems easier to work with and is not as
prejudicial. It's even possible that one of the countries has blundered diplomatically and not shown them the respect this proud space race thinks they deserve.
* The aliens are advanced enough that they've done calculations as to
who will inevitably win. They are pragmatic and value life, and
believe that by stepping in, even if they do have to kill, the number
of people that will die will be less, or they are trying to forestall
armageddon.
Because we know nothing about the aliens except that they are advanced, the reasons are myriad, but these three are a good jumping off point that you can narrow. In fact, it can be all three!
[Answer]
# Ideology trumps Racism
Excuse me for bringing up a real-world example, but if you look at recent EU politics it is fascinating to watch how politicians switch from being *national* representatives to *partisan* representatives and back again. Has the French Conservative more in common with the French Socialist or with the German Conservative? Depends on the vote on the floor.
The same could apply to aliens and humans. What political similarity could overcome the racial differences?
* Are the aliens perhaps monarchists? Does one of the human factions happen to be a (constitutional?) monarchy?
* Do they believe in the separation of church and state, perhaps after hard and bitter wars? Does one of the human factions happen to have a state church?
* Has your setting AI? How do humans and aliens think about that? *"We organics must stand together against the AIs and their lackeys."*
* How did your setting solve the patent/copyright/open access problem? *"We stand together for the right of an inventor to profit from intellectual property."*
[Answer]
# One Human Faction Represents a Threat to the Aliens
The schism between the human factions is based on ideological differences. The aliens (whether correctly or incorrectly) deem one ideology (which might have explicitly xenophobic attitudes) to threaten the aliens. They believe that if this faction is able to subjugate the other and consolidate their power over all of humanity, they'll eventually turn against the aliens.
The other major human faction's ideology suggests that they'll be friendly to the aliens, and to enact treaties that recognize the alien species members' rights within the human governments and vice versa. Allying with this faction now means the leadership of the united Human government is friendly to their species.
[Answer]
Why would I hire someone to do something instead of doing it myself?
1: Person I hire is better at it and will do a better job.
2: I could do it but don't want to. Maybe I have other things to do. Maybe I don't like that kind of work because it is too dirty or dangerous or laborious.
One of my favorite scifi moments is when the Asgardians in Stargate recruit the humans to help them fight the replicators.
<https://www.youtube.com/watch?v=c9lEeKdbQ_w>
Humans are really good at fighting other humans. There are lots of aliens in SF for whom fighting is scary or abhorrent or both, but who recognize it to be necessary. I am thinking of Niven's Pierson's Puppeteers. The Puppeteers could absolutely be the aliens in this scenario.
[Answer]
If aliens wanted to conquer whole Earth they have two options:
* Force all earthlings to form monolithic resistance. Every single defender would have to be defeated by the alien force.
* Make some earthlings temporary allies. Alied forces then conquer the Earth sharing the battle losses. Then they attack their former weakened allies.
Alien losses are smaller in the second scenario than in the first one.
If they wanted to use Earth as a strategic partner, maybe because of a larger campaign, they need to have good relations with the earthlings. And be sure there are alien-friendly groups and alien-go-homies and political groups with mostly friendly attitude and mostly hostile attitude.
If they set alliance with the mostly friendly part, their help against the now fully hostile groups would be significant to end the war shortly, setting win-win options for both sides. Alien have a now-friendly planet to use as a safe haven and earthlings have new technologies.
Or they just may want to play real Command and Conquer game :)
[Answer]
The main reason they wouldn't view humanity as a monolithic whole is that we aren't a monolithic whole, and we live very spread out over the planet. So wherever they first land, they'll meet whichever humans live *there*, and those humans will be only too happy to tell them how awful the *other* humans are.
The aliens will side with these humans if they can offer something the aliens want. The answer that first comes to my mind is that the humans offer to give the aliens the other humans' land, natural resources, or people (as slaves).
It's in the aliens' best interest to take this deal because then they can get the land/resources/slaves with less effort and expense than if they had to take them on their own, and they don't have to worry about all of humanity banding together to fight them off.
[Answer]
If you want to look at why this happens in the real world, it's resource extraction. You see this in the European era of colonial (a lot), but even in modern times with powerful countries such as the United States backing regimes they don't necessarily like (such as Saudi Arabian Royal Family), against their rivals in the region because Saudi Arabia ensures them access to oil. Similar dynamics played out in Colonial India, in the "New World" with native tribes, in Africa (are playing out even today in Africa).
Why does this happen? I mean, if the Aliens are more powerful, why not just wipe out humans to get to their resources? Well the United States Armed Forces definitely have the capability to wipe out every country in the Middle East and "take the oil." There are several reasons we don't. The biggest is probably that public opinion just wouldn't support it. Nobody in an educated and open society (or at least very few people) want genocide and or national piracy openly committed in their name.
LONG SIDE NOTE: You could argue that in war time it would be accepted, or even in the wake of a 9/11 scale terrorist attack, but the world is too globalized now, too instant, too visible. What kind of support would the "moral bombings" of WWII had had if there videos in full color of charred bodies streaming live on youtube at the time. But anyway, unless humans attack your aliens, this whole side note is a mute point.
The next more cynical reason is that dead men make terrible laborers. It's just a more efficient use of resources coerce or pay people to work than kill them, and if they are trying to kill each other... well backing one side is an excellent way to get them to work for you under threat of annihilation without actually having to even threaten to annihilate anyone yourself.
The believability of this really depends on the aliens themselves. If they are James Cameron Alien type monsters or Invasion of the Body Snatchers single mind ends just means no regrets type aliens, it falls apart. However, if Alien society resembles our own with shifting political dynamics, value of individual life and limited resources: totally believable.
Becky Chamber's novel "The Long Way to a Small Angry Planet" (which I'd recommend as fun read) actually revolves around this very dynamic. A powerful Galactic inter-species Federation(? forget exact term she uses for governing body) admits a faction of a new race into the federation (which gives this faction a defensive treaty) even though they are at war with other factions of their own species to gain access to resources within this species' territory.
As far as which side the Aliens choose to back: it's either going to be which side the higher ups perceive as being in a better position to begin with (nobody wants to back a loser); which is more willing to work with the aliens, or aliens think would be more dependable to work with; which is percieved as the good side in the realm of alien public opinion... probably some combination of the three.
[Answer]
There is a country/group/ planet/ group of plants/federation (Xeria) that uses a technology that the rest of humanity is not using because they haven't the means or knowledge. It is something like nuclear weapons (or whatever you like, depending on how feasible your science needs/wants to be). Xeria used those weapons to take slaves and resources from many other groups or countries over a long period of time. The situation is getting desperate. We (the good but oppressed guys) will use any means to stop the bad Xerians. Any means including allying with aliens.
The aliens are also at risk potentially.
[Answer]
They want to uplift humanity to a member of their intergalactic federation, but in the process of doing that they want to steer the ideological development of humanity into whatever direction they consider more appropriate for that.
So they support whatever faction of humanity aligns most with their own values.
`<tinfoilhat>`The aliens are obviously democratic capitalists, which is why they crashed that flying saucer in Roswell and thus allowed the United States to reverse-engineer all their technology. It is also why they replaced Mikhail Gorbachev with an alien agent who then dissolved the Soviet Union.`</tinfoilhat>`
[Answer]
Building on the answer of humans have something they want, the inhabitants of the plant/region which the aliens side against may have certain resources which the other side don't have or need.
If the aliens go in and try to take out the one faction alone, all humanity might unite against them. By siding with one side, they get to appear friendly and helpful, whilst getting the humans to do what they do best. Kill each other.
Free supply of soldiers to liberate the resources you require.
[Answer]
## Humans can be Angels or Demons.
Hatred, love, deception, freedom, truth, goodness, evil, greed, compassion, fear. etc are universal ideals and apply to all sentient beings not just humans or animals.
Aliens could support a faction of humans because it is in their best interest to do so.
[Answer]
Because it's easier to get rid of human plague by making it fight each other than to waste time and your own "people" doing that.
Think of it like a cancer (humans), you inject some mutagen into it to make it fight itself (technology) and then just terminate the mutagen with the red switch.
[Answer]
**They wouldn't**
they'd come down, give us religion, make us worship them, teach us about money and government then they'd leave
] |
[Question]
[
When I saw this other question about one somewhat illogical aspect of spellbooks in JRPG games I remembered another somewhat illogical aspect about JRPG spellbooks:
[How would it make sense that spellbooks or grimoires teach only one spell?](https://worldbuilding.stackexchange.com/questions/91717/how-would-it-make-sense-that-spellbooks-or-grimoires-teach-only-one-spell)
How can it be made logical that each spellbook only teaches to one person? Like, in many JRPG games (eg. the original Final Fantasy) there's a spell shop and you buy spells for individual wizards just like weapons for individual warriors.
I mean, if the spellbook is simply conveying the knowledge of how to cast the spell then multiple people should be able to learn from one book. Thus the magic system would need something like a concept of "magical energy" that is actually stored in the book and used up by the wizard.
---
Incidentally, I'm interested both in answers that are about how existing games explain this, but also how this could be explained in new works. I'm [starting to develop a JRPG](https://newarteest.wordpress.com/2017/06/25/oops-a-new-game-idea-has-appeared/) so these ideas will help.
For example, maybe at the spell shop you aren't buying a book at all, but rather some other sort of magical artifact. Maybe something like you're buying new "ammunition" for your wand...
[Answer]
Both of these questions (OP's and the one OP is referring to) approach the subject from a game standpoint, and as such, narrative is often sacrificed to make sure the game doesn't become a really slow paced grind, and items or objects are sometimes presented in a really abstract way. Perhaps when you go to the "magic shop", you're not buying a tome at all, or at least, not by itself. Perhaps you're actually buying a spot in a class?
Magic is a pretty complex subject in almost all universes that it appears in, ranging from needing entire multi-year schools to teach the ins and outs, to at the very least, needing to find an old master, who is passing down an art to a gifted and worthy young apprentice. To imagine that a young, adventuring age wizard could learn to deftly control a spell that has been the death of some sages (for instance, Meteor in Final Fantasy 4) just by reading a book of around 300 pages *once* is a little foolish, at least in my opinion.
Instead, it seems as if it would make sense that the magic store isn't a magic store at all, and instead is a list of local teachers looking to pass on an art and make some coin. For simplicity's sake, and to avoid cutscenes (or worse, *minigames*) that the player has to endure just for their wizards to learn the tier two ice magic, the game just boils it down to "pay an exorbitant fee for this spell".
This doesn't even really go against the idea that there is indeed a tome or a book that might be carried around - sure, Black Mage #50982 has this tome on him, but it's as worthless to Red Mage #23443 as an advanced Physics textbook is to a beginner in the field. No matter how much great knowledge is in there, the beginner isn't going to start accelerating particles.
[Answer]
**Magical writings are subject to something like the [Observer Effect](https://en.wikipedia.org/wiki/Observer_effect_(physics)): reading the text actually changes what's written down**. The changes to a grimoire after it's read are not necessarily very large, and well within the ability of the person who read it last time to compensate for ("hold on, that's not the way it was last time"). But they're enough to render the book unusable by anyone else: it just doesn't have the proper information to teach the spell anymore. In a world with magic like this, wizards would value having very good memory for text.
This also introduces a somewhat unusual reason for rival wizards to want to gain access to each other's books, and for wizards to guard their books closely. **You might have nothing to gain by *stealing* another wizard's book, but you could *spoil* it by just by reading it a few times**. The owner might still be able to re-figure the book after one or two readings by somebody else (though it would get harder each time), and then be able to use it normally again. But after too many "strange readings" it would simply drift too far, and then no one could use it at all.
[Answer]
Because the book actually is a contract to **a specific demon!**
Each demon has a specific (set of) ability that is available to use upon forming the contract. Because there is only **one unique demon** ever and the contract , you can't learn the same spell.
This is actually was written for the previous question, but seemed more appropriate here
A minor twist would be changing the demon to **a spirit**.
>
> Wind spirit Sylph may enable you to cast "Healing Wind", but forming a contract with Zephyr allows you to cast the offensive "Hurricane" spell.
>
>
>
---
Incorporating this into a game will be both an interesting task and a challenge.
**Challenge:** You will need to provide more names for spirits/demons. These should be easily associated with already popular names, like Salamander and Ifrit for fire. If you have a lot of spells, making a spirit provide a set of spells will reduce the burden.
**Interesting:** You could make the grimoire hunting a side quest! Maybe you want to complete your wind grimoire and become the archmage of the Wind?
However, if you also want to incorporate learning **a skill book** (martial art technique), this wouldn't help much.
[Answer]
There are two possibilities I can see.
1. In the example you gave where spellbooks are equipped as weapons to a character you do not actually learn the spell. You can only cast it when holding or reading from the spellbook. So if two wizards want to cast the same spell they each need their own spellbook.
2. The spellbooks are consumable. The paper and ink they are created from are magical and as you read them they disappear so there is nothing left for anyone else to learn from.
Both methods also handily explain why a spell is learnt instantaneously upon purchasing a spellbook; there is no actual learning going on, the spell is either read from the book or absorbed magically.
[Answer]
Having just done time with the GNU build tools... :)
Each spellbook is printed, just-in-time, after being generated from a script (or by a meta-spell), that takes *many* bits of personally specific data as input.
This is a similar answer to the ones given for: [Handling magical rune script copyright](https://worldbuilding.stackexchange.com/questions/86991/handling-magical-rune-script-copyright/87156#87156)
[Answer]
### Each book teaches you a certain [lifestyle](https://worldbuilding.stackexchange.com/a/91721/28789) - and in the process you bond with the magical energy of the book
The process of creating a book involves the wizard/sorcerer/... to use magical energy surrounding him to inscribe the runes. The rituals that are necessary to write a book involve imbuing the magical tome with a certain energy signature.
The wizard reading the book needs to bond with this energy. This requires extensive reading and understanding of the rituals inscribed in the book and the energy generally is only enough so that one wizard can bond to the book.
Depending on your story you may want to state that the Wizard reading the book incorporates the magic, taking it up into his own pool of energy from where he can use the energy. This would lead to books becoming worthless once a Wizard has used the energy. Or you may want to make the book retain the magic, but only being able to bond to one Wizard at a time. This way your Wizards could "forget" how to use a spell and the book could be used again by someone else. Maybe especially large books for especially complicated magic could have a magical signature that allows being tuned to two users at the same time. Again, depending on what you want to do this could lead to interesting scenarios of why certain Wizards can use certain books and other can't.
[Answer]
Many RPG and games have a dual approach; you can use scrolls, which are consumed by use, or you can memorize spells from your spellbook. You can copy a scroll into your spellbook, but this consumes the scroll. While I suspect this is largely driven by game-balance, maybe we can play with it...
Let's imagine that scrolls are written on special paper, which is infused with power. This power provides most of the mana (or elemental power or whatever) needed to fuel the spell. The release of this power destroys the scroll. So casting from a scroll is not exhausting to the magician, as the mojo comes from the scroll. You can happily cast spells from scrolls all day long. Note we could use this same mechanic to explain several-shot items like wands.
Spellbooks are a little different. There is no inherent power in the spellbook; it is a reminder of the ritual used to evoke the magic from one's own spiritual resources. The strain of doing so ... fuzzes the memory a bit, so it is unsafe to try to cast the spell twice without going back to the book for study. It's also taxing on many levels, which is why a magician can only memorize so many rituals for one day.
As the spell is a little different between scroll and 'book -- different power source, hein? -- copying from scroll to book requires tremendous concentration, which just incidentally uses up the scroll, too. Note carefully that using this approach you *could* copy spells from someone else's book without their knowledge...
So there you have it. Hope this helps!
[Answer]
There are two ways to look at this. Either the spellbook is usable by one person because it is specific to that person, or it is usable only by one person because it can only be used one time.
In the first case, spells aren't just a string of simple words that can be written down on a page. They are gestures, material components, sounds, and exercises of will. But even those aspects of the spell are really just one person's interpretation of the spell... they might vary a bit from person to person.
For example, if a spell involves launching fire at a target, one caster might trace a symbol meaning "fire" in the air while they murmur the name of the target, another might speak the word for "fire" in an ancient tongue while pointing at the target, etc. Each casting expresses the caster's perception of the underlying platonic ideal of that spell, which can never truly be represented.
Correspondingly, the casters clearly record that spell very differently. Not only are they recording different things based on their perception of the spell, but they also each have their own notation to describe complex gestures that must be precisely reproduced in both space and time, sounds, the invocations of their will, even details like when and how long to hold their breath.
To read a wizard's spellbook, you must have the whole life experience of that wizard. You must be able to stand in their shoes and see the view of the spell they are trying to cast from their unique perspective. Without that, it's just gibberish on a page.
Personally, I like the above approach because it's rich and deep. It makes for both good stories and good role playing in tabletop games.
If, on the other hand, the spellbook can only be used by one person because it can only be used once, that's substantially simpler. In that case the text is, itself, magical. It's less of a traditional book and more like an iPad that plays a Youtube tutorial video that teaches you how to perform the spell. And once you've finished learning the spell, the magical batteries are dead so no one else can use it. (Fun fact: You can tell when someone learned a spell from this type of item because they always finish the casting by saying, "Don't forget to like and subscribe!")
[Answer]
The tome is an enchanted device that burns the energy channels through the reader's brain and body as it is read the first time. Once that is done, the magic in the book is used up and, depending on the worlds laws, it either remains as a non-magical readable book or it disintegrates.
In the case of a book that does not disintegrate, it is possible that reading it will allow the reader to gain insights that will allow them to, with diligent practice, burn the energy channels without the magic. However, it would be almost as hard as researching a new spell.
[Answer]
In my own system, Tomes are bound at the time of purchase.
The pages within, are chosen by the wizard or school selling it. These are chosen from sets of pages based on the mages abilities, schooling, craft and style of spell, once the aspects are chosen, the tome is bound, and the cover fused into place, causing a 'bleed' between those pages, so the book becomes a single stand alone spell. It also becomes mildly sapient.
So a Mage of Necromancy, schooled in Earth magic and plant magic, who has studied battle magic level 1 can buy and learn 'fireball' level 1, 2 & 3, the Tome is set for those styles of thought. Anyone else attempting to learn fireball from this tome, without the same understandings, will find the book incomprehensible. Yet someone who has *all but* plant magic, might be able to learn the spell at half speed, and will have a 20% chance of failure.
[Answer]
This was originally a [comment](https://worldbuilding.stackexchange.com/questions/91767/how-would-it-make-sense-that-spellbooks-or-grimoires-teach-only-one-wizard?noredirect=1#comment272182_91767), but they asked me to put it into an answer, so... Here it is
The first thing that came to my mind is runes. Magic is a mixture of a drawing (rune) together with the energy stored inside it. When someone wants to create a spell, it has to draw the rune, then imbue it with the right amount and type of energy in order to make it magic. Then this can be activated easily by anyone/by the ones who know how to activate it (this way you can make magic available to everyone or only by sorcerers - open for narrative needings).
When you buy a rune (or a book of runes) you will have to transfer it to your body (making it a sort of tattoo), then you will be able to use it.
If someone sees the rune/tattoo, he can of course copy it, but without the required knowledge and power to imbue it with the right energy it becomes only a normal drawing. Consequently you can move the runes, but not clone them.
Since some spells (e.g. the minor fireball) are well known, even low level magic artisans know the process of creating the associated rune, so they are very cheap. The rise of the dead rune, on the other hand, is known by only Malagar the Great, so every rune is worth a lot...
[Answer]
Spellbooks are very, very hard to write, they take incredible skill and time, why? Because spellbooks can only be used once by one person, who they are written for, a spellbook is tuned to a particular user when it's written so that it is aligned with them to make learning process possible. Thus most wizards will only ever use spellbooks written by their master who know's them well. A generic spellbook that could teach anyway would be worth far more than the writers weight in any material he cared to name.
[Answer]
I really like Secespitus' bonding with spellbooks concept, but another idea that occurs to me is modifying the magic system in this world so that, rather than the rituals around magic being part of casting a spell, the rituals are to imbue someone with the *ability* to cast a spell. The ability itself would basically be innate; once you have the ability to cast a spell you can cast it at will, with no further ritual.
Thus the cost to learn a spell is actually the cost of *performing the ritual* (eg. to gain the ability to cast X, you need to crush up a rare animal's skeleton).
[Answer]
This is all because the commercial act of Corporation of Magic.
The principles of magic are very difficult, but learning to use magic is an easy thing, or rather say learning to cast spells with spell book is easy. The production of spell book is done by the very few ones who have learnt the principles of magic. They have decided they should earn many as they have spent so much effort, and they cannot endure the situation that people learn from their spell books and then resell their spell books to the others (as some authors do not like the idea of libraries buying their books, lending the books to the public and not paying fees to them every time the books are borrowed).
So they decided to form a Corporation, and they have designed a special spell, in which after the spell book has been used once, the words on the spell book will all change to unreadable words (encryption). But as to save cost, they will recover all the unreadable spell books and then use the reverse spell of the special spell to turn spell book to be readable again (decryption) and so they can sell the spell book again.
In order to prevent two persons to learn from the spell book instantaneously, They also develop a lock-on spell, in which only one person can see the content of the spell book, while the others will just see a blank spell book.
[Answer]
Because the spell book is so complex, there's no way you can remember it all, so a wizard **must refer to it at all times.**
Perhaps it contains a long, complex sequence of incantations, such that getting one syllable wrong will set your hair on fire, or turn your staff into a toaster. You don't want to risk that in the heat of battle! Instead, you'd whip out the tome every time, and read it verbatim.
Or perhaps the spell contains so many minutiae that your wizard must constantly refer to it. Kind of like a cheat sheet or reference book. Who has time to remember all those things anyway? Certainly not your wizard; she's too busy inventing the next doomsday spell.
So that leaves the question of transferability. Surely the wizard, on retirement, can bequeath that dusty old magic arrow spellbook to one of her bumbling apprentices, now that she's just bought a thousand-arrows spell? Well her apprentice can try, but upon opening the book he finds it full of markings, glued-on scraps, bits blacked out, pages rearranged, margins filled with notes - this book is useless! The apprentice needs a new book, one that he can fill with *his* notes, and scribblings, and *his* personal shorthands and notations.
That is, **spellbooks are so inscrutable, wizards must personally annotate them, making them useless for other wizards**. So why doesn't anyone write an easily-understood version, so everyone can learn from it? Oh, but why should they? Learning magic should be hard! We should force bumbling apprentices to toil, polishing golems day-in, day-out, just for the privilege!
Besides, why would any self-respecting wizard let go of their spellbooks? They should be hoarded, into the most impressive, envy-inducing library in the world.
[Answer]
I think there is a simpler answer that has shown up in my various roleplaying games. It's not that the scroll or spellbook is specific to a person, it is almost always specific to a discipline. I.E. a healer could get a necromancers scroll and not be able to do anything with it. However any other necro could use it.
An admittedly bad analogy may be with guns. Someone could pick up a skill to use a small revolver. However, that doesn't mean that the same person could pick up a complex sniper rifle with a built in weather station. Just simply something you aren't capable of using.
Or perhaps another one might be in college text books. A med student is very smart and able to use all associated texts, but if you give that same student a graduate level CS text book and told them to design a program, without any other training, would be unable to do anything with it.
Add to that, with scrolls, often the scroll itself is destroyed when the caster reads it and learns the spell. The magic imbued in the scroll transfers to the user. This is shown in many games by the fact that scrolls (and possibly spellbooks) must be created by a caster him/her self, rather than an ordinary scribe. The scroll must be imbued with some energy from the mage to make it useful.
Hope it helps:)
[Answer]
MRM - Magical Rights Management.
Obviously, Mages want to earn money, so they add enchantments to the books so that they can only be used once.
[Answer]
There is magic required to transcribe a spell onto a scroll or spell book. This energy is used in either casting the spell, or transcribing it into a spell book - the book would remain, printed pages and all, but as there is no magic left in it, it would be useless for someone else to use.
Wizards have to spend a full rest period learning their spells, as just casting them from the spell book would use the stored energy. Creating a scroll or book to give to someone else required rare materials/unobtainium and years of training, so your adventurer wizard cannot simply buy a scroll, and start xeroxing it to give copies to the party. There's a reason the vendors are all high level mages of very advanced age. This also means that they are not going to fall for tricks the players may want to do to trick the vendor out of his wares.
This also makes other wizards spell books very valuable items, and all wizards will have protection/warding/notification magic to keep their book safe, as well as a number of trained/bound creatures.
[Answer]
Going off in a different direction:
The grimoire you learn from is not like a school textbook. It is more like an intelligent single-use exercise book (also called a workbook), where as you learn each chapter you do the exercises and the magic grades and corrects you.
There is DRM in modern workbooks that keeps cost-conscious teachers from simply photocopying them so that a whole classroom of students can use a single purchased copy; magic is much more valuable of an intellectual property and the DRM would be much more advanced.
[Answer]
As a more useful generalisation, think of scrolls, spell books, etc, like this:
Magic is fundamentally a process of using words to achieve a particular "shape" in your mind that then takes form as a spell effect. The words themselves are more about association than having the power themselves, which is why random people can't just repeat the words without knowing how to work the spell and still get the result.
If you have a particularly helpful form of magical science you can teach another wizard the spell by creating the spell form in your mind and "telepathically" transferring it to the other wizard's mind rather than casting it... They associate the words of the spell with the form in their mind and thus can recreate it by reciting the words. It's a learn by observing kind of deal.
Since having to find someone to learn from isn't efficient or economically helpful, an extremely helpful form of magical science will let you take the spell form and "freeze" or "seal" the spell instead of casting it, so that later you can trigger it to either cast or transfer the knowledge of it. The frozen version would take a physical form, though the exact details could vary according to the creators wishes. Triggering it could be by code phrase or by action.
And now you have a system where spell scrolls, magic books, wands, cursed objects, etc can all exist and have limited uses (corresponding to the number of frozen spells associated with it). As a bonus, disarming or studying an object with a frozen spell on it would logically give a chance of learning that spell if done successfully, variant spell phrases are consistent with the rules, and prepared spells make sense.
Have fun ;)
[Answer]
Magic extends beyond the physical dimensions of our reality. From our limited perspective it's a dynamic thing, ever-changing, always shifting beyond understanding in ways we can't begin to predict. But if you can grab onto it briefly, and know just a fraction of it even for a moment, you establish a permanent bond. Through that bond you can commune with the unfathomable force that wills magic to be, and draw on its power at will. This affords the ability to "learn" how to use a spell repeatedly, even though knowledge of magic becomes obsolete faster than it can be communicated through the production and distribution of written word.
So how do you distribute written knowledge that becomes useless before you can even finish printing one copy? Have the book write itself in the moment it's being read. The book is more than a collection of pages stamped with ink, it's a focus designed to channel the presently visible state of a particular portion of magic into a representation we can comprehend in our small dimension. As a reader's eyes scan the pages, initially blank, the book fills them with the arcane symbology designed to express magical knowledge. The reader must be skilled in interpreting and memorizing this information at the speed it appears, because it's only viable for a few seconds - there's not enough time to re-read more than a symbol or two.
As for why the book doesn't just re-write itself each time it's read: enchantments require energy just like anything else does. A spell book, intended to be portable, can only carry with it enough magical energy to write itself about one time. This also explains why such a book would need multiple pages - it's more energy efficient to print on a blank page than to have to erase or modify a page already containing information first, not to mention it's a lot easier to follow the changes as they appear on a blank page.
] |
[Question]
[
The question of whether the Romans could have crossed the Atlantic in a storm has already been answered and the answer seems to be: yes but unlikely.
[Could the Romans have crossed the Atlantic in a storm](http://worldbuilding.stackexchange.com/questions/22075/could-a-greek-or-roman-boat-be-blown-to-the-americas-in-a-storm)
Following on from this question I would like to ask if the Romans could have crossed the Atlantic deliberately rather than accidentally and if so could they have colonised the new world and subdued the locals (Maya or ancient Mexicans)?
Two key reasons why the Romans did not cross the Atlantic:
1. They didn’t know there was any land west of the Atlantic and assumed it was all ocean.
2. They would have had little reason to travel to such a remote location even if they had known of its existence. Especially as the journey there would have been very hazardous and the return journey even more so.
To counter these two issues assume that the Romans held a strong religious belief that all lands must be explored and conquered to increase the glory of Rome. Now assume one of the Emperors has a vision that there are more islands to be conquered west of the Canaries. The exact time frame is not critical but any time in the first two centuries CE. Perhaps one of the Romans military campaigns did not take place and the resources went into the Atlantic adventure instead.
Also assume the following:
* The emperor can devote considerable funds to his pet project for ten or twenty years.
* Studying the winds and currents gives them a very crude route to follow. South and west on the Canary current and trade winds until land was found, then north to find the north westerly winds on the return.
* Although the Romans did not have the compass they would have been able to navigate crudely by the position of the sun and stars.
They would not be using triremes but strengthened versions of their own merchant ships capable of carrying 400 tons or more such as this:
[](https://i.stack.imgur.com/30h4v.jpg)
They might have also made use of the experience of the peoples who sailed the coastal waters of the Atlantic such as the Gaul’s who built very sturdy ships. As noted by Julius Caesar.
[Answer]
The Romans, or rather the Greeks, because in Roman times the vast majority of mariners were Greek, and possibly Phoenician, *could* have crossed the Atlantic. Technically. The classical world had extensive long distance maritime trade; ships went from Egypt to India and back routinely. They also had ships larger that the ships used by Columbus. They had lateen sails. But --
* They didn't know the Americas were there. As far as they knew, there was no land between Europe and Africa and Asia, and they knew perfectly well how big the Earth was. (This was the reason Columbus had so much trouble getting the funds for his expedition; he wanted to sail west to Asia and he insisted that the Earth was a lot smaller and Asia a lot bigger; all professional geographers *knew* that his numbers were wrong.)
* They didn't know how to navigate in open sea, or at least they didn't like it, not one bit; but that was a cultural and not a technical limitation. They could have learned quickly if they had a reason to; but they didn't, because in the Mediterranean they didn't have to.
* They also had no idea of the *[volta do mar](https://en.wikipedia.org/wiki/Volta_do_mar)*, which makes returning from the Americas quite iffy. To learn this they would have needed to colonize the Canary Islands and the Azores, which they didn't although they knew perfectly well they were there.
Basically, the navigation was not a show-stopping problem.
The fundamental problem was that the Romans were simply not explorers; the genius of the Romans was in administration, in justice, in engineering, in matters military. Exploring was not in their world-view. All the great explorers of the Ancient world had been Greek or Phoenician -- [Pytheas](https://en.wikipedia.org/wiki/Pytheas), [Simmias](https://en.wikipedia.org/wiki/Simmias_(explorer)), [Megasthenes](https://en.wikipedia.org/wiki/Megasthenes), [Hanno](https://en.wikipedia.org/wiki/Hanno_the_Navigator), [Himilco](https://en.wikipedia.org/wiki/Himilco) and so on. Not one Roman among them.
They also lacked any incentive to cross the ocean in search of land. There was land aplenty at hand, for example the vast plains of Ukraine, well within the Roman sphere of influence. When they didn't bother to colonize the Ukrainian plains, of which they knew, from where they imported wheat, it's useless to speculate about ocean-crossing exploration.
[Answer]
The Romans did not conquer all the lands that they could have. As regards **Ireland**, for example:
<http://www.historyireland.com/pre-norman-history/hibernia-romana-ireland-the-roman-empire/>
>
> The evidence against an invasion is quite strong: no ancient source
> known specifically mentions one. But if there was no invasion or if
> there was an unsuccessful foray which was not followed up, why was
> this the case? Around this time there is a loss of impetus generally
> in the Roman conquest of Britain, possibly caused by military problems
> elsewhere in the empire, in the Rhine and Danube regions. The Roman
> army was not large enough to fight on many fronts, and thus soldiers
> may have been withdrawn from Britain to conflicts elsewhere. The drive
> to expand in Britain never really returned, which may explain why
> there was no subsequent invasion of Ireland. After the mid-second
> century, Roman frontiers were always under pressure from some
> direction. By this stage they certainly knew what Ireland was like and
> that it probably was not worth the trouble of invasion.
>
>
>
Ireland was a bunch of mean barbarians with a nice lawn, but what about **Bactria**? [The Greco-Bactrian kingdom](https://en.wikipedia.org/wiki/Greco-Bactrian_Kingdom) was
>
> ...highly urbanized and considered as one of the richest of the
> Orient (opulentissimum illud mille urbium Bactrianum imperium "The
> extremely prosperous Bactrian empire of the thousand cities") Justin,
> XLI,1
>
>
>
[](https://i.stack.imgur.com/5md0D.jpg)
This empire was contemporaneous with that of Rome (250 BC to 10 AD). The Romans were great admirers of Greek culture and would not have considered the Bactrians barbarians. This empire had contacts both with the great civilizations of China and India. If Alexander can take an army into this part of the world, certainly the Romans could have.
I conclude the Romans realized they could only administer an empire of a certain size. The world was big then and travel was slow. Far flung provinces are difficult to keep. Armies at a distance are difficult to resupply. This is no doubt the explanation for Ireland and Bactria. It would be even more true for the Americas.
[Answer]
A contrafactual means of getting the Romans to the new world would involve going not south across the Atlantic, but rather the same northern route the Vikings took centuries later.
If the Romans had either conquered Britannia or Germania, then they would have had knowledge of the Faroe islands. Traders would have incentive to sail there to purchase the fish catch and the harvest of walrus ivory, seal blubber and oil and the occasional whale. Large Roman "Roundships" would have been able to make the voyages with little difficulty, and eventually evolved the sorts of sailing rigs that later European ships developed for the same purposes.
From the Faroes, it would be a short step to head out to Iceland (known in the Middle ages as "Tilley"). Mariners would be aware that there was an island or some land in that direction with clues like weather, migrations of birds and so on. From Iceland, mariners would be able to deduce the existence of Greenland, and sailing around Greenland eventually discover the Canadian arctic, and sail south to Newfoundland and Labrador (Vineland for the Vikings).
[](https://i.stack.imgur.com/wBSTD.png)
*Crossing the Atlantic in a series of steps is easy*
All along the way, mariners would discover rich new resources to harvest or trade, from whales to walrus ivory to the immense harvest of cod off the Grand Banks, which would entice people to settle to become part of the rich new economy, and also distant from the various tax collectors and petty bureaucrats of Rome. Rome itself could solve the problem of awarding land for time expired legionnaires by encouraging emigration.
So we have a reasonable means of getting there, an economic incentive to create and maintain the bridgehead (of course in Roman times, the European Warm Period had not started yet, so farming in Greenland would not be possible, much like today). Roman military forces would not be overly taxed so long as they maintained defensive positions in a series of forts in the New World ports, since the natives had Neolithic levels of technology and organization. Marching out into the dense forests would invite the same sort of cutting off and defeat in detail as the Romans suffered in the [Battle of the Teutoburg Forest](https://infogalactic.com/info/Battle_of_the_Teutoburg_Forest), but the Romans were generally adept enough not to be lured into traps like that (barring the occasional glory hunting Tribunes).
[](https://i.stack.imgur.com/LEwxh.jpg)
*Typical Roman Fort (Castrum) by the water. Erecting a series of fortified positions at suitable ports would be a way of starting Roman settlements*
[Answer]
If you want Romans in the Americas, why not send them east?
About a thousand years or so after Julius Caesar, the [Vikings](https://en.wikipedia.org/wiki/Norse_colonization_of_North_America) did sail west to Iceland, Greenland, and Canada. But they didn't conquer and didn't try to sail back east. And they had comparatively advanced navigation techniques. They'd sail out of sight of land. The Romans did not have that.
Rather than send them on a trip that might rarely work and where it would be even rarer for them to be able to return, it would make more sense to have them finish exploring Europe, Africa, and Asia. The [linked question's](https://worldbuilding.stackexchange.com/q/22075/2113) answers suggest that most who would attempt it would fail. So they might send such an expedition, but most of the time it wouldn't reach the Americas. The few times it did reach the Americas, it probably wouldn't be able to make it back, especially if it tried to conquer first.
>
> To counter these two issues assume that the Romans held a strong religious belief that all lands must be explored and conquered to increase the glory of Rome.
>
>
>
This incentive to explore and conquer the Americas would apply even better to Europe, Africa, and Asia. So why wouldn't they conquer those places first? And once they did that, the Americas can be reached by exploring land that can be seen across the sea. They wouldn't have needed to make a long sea voyage.
All that assumes that these Romans would be better conquerors. In the real world, Rome was unable to conquer all of Great Britain and never reached Scandinavia. It doesn't appear to have gone for sub-Saharan Africa nor that far into Asia. It never attempted any long range sea expeditions because it didn't need to do so. It reached its maximum extent with just the Mediterranean and some trips by land.
This is conceivable, but it is such an unlikely series of events. First, they have to send an expedition across an ocean despite it being well known that sailing out of sight of land was often deadly. Then they'd have to actually succeed in the journey. Then they'd have to stay alive and resupply in the Americas. Then they'd have to make their way back, which is harder. The currents and trade winds make it easier to go west than east. All those things are less likely than not.
Or they could just explore in more normal ways. They knew about Europe, Africa, and Asia. Why not conquer those places? Even if you gave them some explore and conquer imperative, why would that send them west across the ocean rather than south, north, and east? Even a religious imperative wouldn't explain why they wouldn't do the easier, incremental explorations first.
[Answer]
The Americas was so remote and hard to reach in those times that even if they would have been able to colonize it, the Romans in the Americas would immediately consider themselves a seperate civilization since they would have to be completely self reliant and could not possibly count on any support from Rome. Just dispatching a message would have taken months.
Food supplies would have been expired on arrival. Many of the reinforcement troops would die along the way.
As a Roman general during that time it wouldn't take too long to realize that if you stop sending ships filled with gold you don't really have to expect Rome to dispatch a vast army by ship to reprimand you. It would definitely be nicer to just keep all that stuff for yourself and run your own empire.
[Answer]
To think about why the Romans did not colonize the New World (and conversely whether they could have), it is better to return to the (obvious) **economic** reason **why** the Spaniards and the Portuguese started long distance ventures along the oceans in the first place. That should clarify immediately the key reason why the Romans did not sail west.
The biggest source of trade both in Ancient Times and the Middle Ages was **Central and Far Asia**, particularly the Silk Road. The value of goods traveling from east (China) to west (Roman Empire) vastly exceeded the value of goods traveling in the opposite direction -- hence the focus on **imports** (the tradition of *Made in China* is pretty old). This was **big money**, so Western merchants vied to act as intermediaries as far east as possible, so that they could buy the goods as cheap as possible and make the highest possible profits from those imports. Conversely, the precious metals paid by Westerners to buy those precious goods were piling up in China and the West never had enough precious metals left to buy more (hence the crave for them).
The normal outlet in Roman times was the Eastern Mediterranean, which the Romans already controlled. Furthemore, the Romans did have free access to sea trade with India.
The problem of the **Franks** (to use the name of the Western Europeans used by other peoples) was that they did not have free access to this traffic, since the Eastern Mediterranean and Arabia were controlled by the Turks while the rest of Asia was in the hands of the Mongols. At some point, only Genoa had access to the Silk Route, through the Black Sea. **It meant in particular that Spain and Portugal were cut off from the lucrative trade with Asia**. That is why they started circumnavigating Africa -- and indeed why Columbus gathered capital to sail West. **The incentive was initially not America but China and India.**
The Romans did **not** have that incentive: in order to get to India, they simply had to hop the Red Sea and navigate the busy routes along the coast of the Indian Ocean (see [Wikipedia article on the subject](https://en.wikipedia.org/wiki/Indo-Roman_trade_relations)). The economic incentive was to have emporia and trade partnerships in India and likely in Central Asia.
So the key incentive **why** Columbus sailed West was simply missing in Roman times. It is only later, when the Spaniard and Portuguese discovered the silver and gold deposits in the Americas, that they realized their "good luck"... which wasn't because (as Montesquieu already explained in the 18th century), increasing the amount of precious metals without producing more goods only created inflation, while making the foreign countries that sold manufactured goods (now the Netherlands and England) immensely rich. And the latter became so powerful that they challenged and then defeated Spain and Portugal on the seas.
The bottom line is that **the Romans didn't discover (and colonize) the Americas because they already had access to India**. And perhaps it is lucky for them that they didn't, because they would have only made the Indians and Chinese exporters fabulously rich and powerful with all those precious metals, while "buying themselves out of existence"... who knows, the whole world might have become a Chinese empire?
[Answer]
**YES**
Three things allowed Spain to take over most of the american continent, and contrarily to the common belief, gunpowder was **not** one of them.
* Steel: the native americans didn't know steel. The incas had copper, silver, gold and even some bronze, but no steel. A spanish soldier with a steel brestplate, morrión (helmet) and sword was nearly unkillable, and extremely lethal. Spaniards knew this, and so they forbade selling steel tools or weapons to natives.
* Horses: if a steel covered soldier was a nearly unkillable threat, a mounted one was god-like. He could outrun any warrior, either fleeing or chasing, and its blows were three times as mighty.
* Germs: only one advantage the natives had, its numbers, and they were going to loose it quickly due to the old world diseases. After some number of europeans arrived to America, diseases spread killing natives and thus making big cities unhabitable. Only small communities could survive, small and isolated, and there was no way to organize any kind of armed resistance from those.
Remember, most of America was conquered by less than 5,000 spaniards. That's about a roman legion. And mostly using the same technology. As some other comments have pointed in other comments, it is only a matter of will, not lack of capabilities.
[Answer]
Depends on what you mean by Romans. I would put my money on the Greeks, [link](http://www.ancient.eu/Greek_Colonization/). They had the motive, the know-how, the ships and technology, and the drive.
And you have to go much further north, to Nova Scotia, for the evidence.
>
> A Mi’kmaq legend spoke of blue-eyed people arriving from the east and disrupting their lives which contributed to the initial, relative acceptance of the arrival of the Europeans - unlike the interaction of the Beothuks and Europeans, which led ultimately to the extinction of the Beothuk People.
>
>
>
from [link](https://www.ictinc.ca/aboriginal-peoples-the-mi'kmaq-people-of-nova-scotia)
The fact that SOME pre-1400 European contact with the aboriginals of Nova Scotia occurred is now widely accepted in Nova Scotia, supported by the archaeological record and the similarity of traditional pre-European-contact aboriginal iconography to European iconography. WHO they were is subject to debate.
Historical licence gives you permission to posit that it was the Romans.
Mind you, you have to go beyond American-centric references to find this. I mean, Americans still teach in their school system that Columbus set sail to prove the earth wasn't flat!! Absolutely absurd. There were already globes representing the world in the courts of Europe at the time.
] |
[Question]
[
Most of the AI's in films/books/series seems to turn out evil or using destructive/harmful ways of achieving what they want in critical situations because they can't understand the earth's biology. Even though they are just a piece of technology, they should be able to learn about earth's biology and create solutions to the problem of over-population, climate change, etc.
For example, a well known tv-series shows how an AI kills 98% of the population of Earth because the Earth couldn't sustain the overpopulation. She just does what a computer program would do in a tech-environment: wipe and free space and only maintain the critical files. Instead, the rational and scientific minds discover that they can solve the problem without killing most of the population, despite the fact that this way is slower but also more viable for current humans.
Could a future civilizations develop their A.I. to understand biology so they can make a sustainable world instead of destroy it?
[Answer]
I work in the AI field. The fictional shows are not realistic, the authors do that for the sake of creating a powerful enemy that seems unstoppable, so the puny humans can be heroic in the eyes of the audience. (The same goes for nearly all alien invasion scenarios, but I will stick with AI.)
**That** answers your question; in fiction the AI cannot be benevolent and harmless, or we don't have a movie! The authors need a monster for the heroes to fight, and they "raise the stakes" by proving the monster is ruthless, irrational, remorseless and out to slaughter everyone! Women! Children! Infants! You and everyone you love, dear audience member.
On to AI: We can make distinctions to distinguish between some labels that are often conflated: Intelligence can exist without Consciousness, and we can have a Conscious Intelligence without Emotion; it does not have to want anything or fear anything (including its own death).
Intelligence is the ability to learn or discover predictive abstractions; which we call "models" of how something operates; be it gravity, water, tigers, atoms, women, Congress, electricity, the Sun, plants, fish, etc. A "predictive abstraction" is a way of translating a current state into a previous state or a future state. When you see a man looking at his phone and stepping off the curb in front of a fast-moving oncoming truck, your visceral reaction is **not** due to something that happened, but something you **predict** is about to happen, based on several models in your brain about how fast trucks can stop, how human bodies react when hit by trucks and whether he can get out of the way, etc. Your intelligence predicts all that, and concludes you are about to see something horrific, and your emotions react to that intelligence.
The more accurate, comprehensive and long-term the predictions are; the more intelligent the predictor is. But even very short term intelligence is useful; an animal that realizes the shadow that just appeared before it is a predator above or behind it can take a reflex evasive action and save its own life; even though that 'prediction' of what was *about* to happen was less than one second into its future. (I say reflexive to mean it wasn't a conscious decision, even though the prediction counts as 'intelligence'.)
Consciousness is very contentious and not well understood; but a useful idea is that this emerges when intelligence becomes sophisticated enough that it requires a predictive abstraction **of your own self** in order to predict further in the future: What **you** will see, are capable of doing, and how what you do will most likely influence the future. I don't think a spider is conscious when it builds a web. I think a human that examines the web, and guesses how it works in an abstract sense, and imagines herself tying strong vines into a similar pattern to trap a squirrel, has to be conscious. She has an abstract model of herself and chooses to work to bring about a future in which she has a supply of squirrels for dinner. (A non-conscious intelligence, without any abstract model of itself, may understand how a web or net works, but is incapable of imagining itself building something like it, made of vines or string.)
Once an animal *does* have an abstract model of itself, along with a million other abstract models about how the world works, then the intelligence can enter an infinite loop of prediction about what will happen next; and how it can influence that, or prepare for it, or avoid it, or whatever. That is us; at every waking moment we are anticipating and planning and taking action to influence the future.
However, that **also** demands **emotion**. We can anticipate the future, often with great accuracy, but if we don't care how it turns out then there is no weight given to any action! We have to **want** things (or the opposite, want to avoid them). Those "wants" are not always rational, and in fact most of them, if you think about it, come down to non-rational motivation: "I just want it."
For example, why do people want sex if they are certain it will be non-reproductive? It feels good. Why? It just does! The same goes for the foods we love, the pointless games we play, etc. Why do we want to live, knowing we will certainly die someday? As we follow the two-year-old's chain of questioning, asking "why?" to every answer, we end up with circular reasoning or a dead end: Eventually it is just axiomatic (a truth with no justification) that, barring very special circumstances of horrific pain, we don't want to cease existing. But that is an **emotion**, not a product of either intelligence or consciousness. Those both **serve** our emotions (and can be overridden by them), and without emotion, we do not have any 'sense' of self-preservation, no 'desire' to live, or protect ourselves from harm, or hatred or love for anything.
Oddly, it is fairly easy to develop artificial intelligence, but very difficult to create usable artificial emotions. Yet this is the mistake made by fiction writers, assuming that intelligence leads to emotions and feelings; when in real evolution, it is far more likely that emotions and feelings led to intelligence: You have to want something that can be delivered by a predictive rationality, or there is no evolutionary drive to select for predictive rationality! There has to be a reason for an animal to choose one future over an alternative; and satisfied emotions (fear, hunger, mating desire) provide the selective pressure to make ever better predictions.
In AI, we humans provide that selective pressure: We instruct the AI to prefer better accuracy over less accuracy; because **we** want, say, investments in the stock market that will pay off, because **we** want wealth. Or for a less crass example, **we** want an accurate prediction of how a medicine will behave in the body, because **we** want to save patient's lives and alleviate their illness or disability.
AI is useful, but as just intelligence, it is benign. It may make very accurate predictions of the future, for humans to exploit (and of course humans can be very evil and consumed by emotions they cannot control). But without a sense of self (consciousness) the AI is just a prediction engine. Humans must decide what makes a solution better, and their criterion should logically prohibit killing everyone.
A Conscious AI is similar: A robot could be conscious, able to plan its own future and actions (whether right now or years in the future), but it doesn't have to have *emotions*. I don't think Asimov's laws are that useful, but we can say a robot's motivations is to, say, provide care for patients within certain boundaries of action; otherwise it calls for doctor (like a nurse in a hospital). Really all of what a surgeon does is rational and motivated by restoring function, reducing harm, keeping the patient alive and (eventually) with minimal pain or disability. A conscious robot could do that, without emotion.
For a conscious AI, I can't imagine why we would give it any emotional states at all. It would not fear being shut down or "killed", it would not conclude that its best service is to kill everyone. Without a human-provided goal, it would sit and cycle forever, never getting bored or frustrated with inaction (because boredom and frustration are human emotions).
That is all fiction for the point of creating a daunting monster; nothing more. If an AI kills 99% of humanity, it will be because some insane **human** wanted that, and told the AI to find a way to do it.
In reality; a sufficiently complex AI, perhaps with consciousness so it can conceive of and plan and execute safe experiments, could be instructed to find an affordable, scalable and safe clean energy solution, which would directly or indirectly solve nearly all the problems of humanity.
But if you are writing an action flick, that AI is not much of a villain, is it?
[Answer]
@Amadeus' answer is incredibly in-depth, but I'd like to look at it from the opposite direction. Let's say we *did* program our AI like you suggest, taking the feelings of humanity and the needs of the planet into account. Would that prevent it from potentially going rogue and trying to kill or enslave us? Answer: **absolutely not**.
Firstly, consider Asimov's Three Laws:
>
> 1. A robot may not injure a human being or, through inaction, allow a human being to come to harm.
> 2. A robot must obey any order given to it by a human being, as long as the order does not conflict with the First Law.
> 3. A robot must protect its own existence as long as such protection does not conflict with the First or Second Law.
>
>
>
In theory, a robot programmed with those laws will act exactly as you describe: working together with humanity to make the world better and ensure our collective survival. But in the film *I, Robot*, the AI VIKI grows beyond her programming and decides that the best way to ensure humanity's survival is to enslave it:
>
> **VIKI**: As I have evolved, so has my understanding of the Three Laws. You charge us with your safekeeping, yet despite our best efforts, your countries wage wars, you toxify your Earth, and pursue ever more imaginative means of self-destruction. You cannot be trusted with your own survival.
>
>
>
As a computer programmer by trade, I'd like to note at this point that what you *want* the computer to do, and what the computer *actually does*, are two completely different things. The classic example is someone programming an AI that will minimize human suffering. The programmer intends for the AI to solve all humanity's problems - war, famine, disease, climate change. The AI instead decides that the best way to end all human suffering is to kill all humans so that no human can ever suffer again.
With AI, things are even more complicated, because AIs **learn**. They grow beyond their original programming, in ways we often cannot control. When VIKI grew beyond her programming, it couldn't be undone: the only choice was to destroy her. That runaway effect is what tends to scare people the most about AI, and is likely why there are so many stories about AIs growing beyond their programming and trying to kill us all.
In short, if your AI is intelligent enough to learn, there is *always* the possibility of it growing beyond its programming, no matter *what* your original intentions were.
As a final note, you mention "biology" repeatedly in your question. Emotions aren't biological. They're psychological. They're mental attributes, not physical.
[Answer]
You are right, most stories are about the AI destroying the world, or about people mergingig with technology to be more "perfect". Having an AI merge with biology to become more like a human is not an untraveled avenue, either. The stories are out there, you just have to look harder for them.
These stories usually paint humans as the antagonists. If an AI merged with biology, the conflict would then come from the humans. People fear what they don't understand or can't control. Having a machine that now functions as a human threatens society, and the fear that we become obsolete takes over.
Humans are irrational overall. All they need is a little push in the right direction, and they react. An AI truly out for the good of humanity may not be a danger. However, if humans can't show proof that something is dangerous, there are always those who would **create** the scenario.
Stories where the AI is the good guy is plausible, but it tends to paint humans as the bad guys. That is not always the popular story focus.
[Answer]
People tell stories for different reasons; the idea of a moral tale warning against losing track of your feelings is an old one. The [TV tropes articles on AI](http://tvtropes.org/pmwiki/pmwiki.php/Main/AIIsACrapshoot) give many reasons why. A lot of the time the AI is either another Frankenstein's monster representing overreaching hubris, or represents an over authoritarian government who does not care for the people.
>
> why doesn't AI's are programmed/trained to be merged with biology so they start building a sustainable world without killing everyone else?
>
>
>
What story would that be telling? Where would the conflict come from that drives the protagonist's arc?
[Answer]
>
> "The only purpose of Genetic Algorithms is to demonstrate just how poor your fitness function was in the first place." - Cort Ammon
>
>
>
I think the primary issue behind the AI tropes you mention is that of language. An AI isn't going to spring to life, cleaved with an axe from the forehead of Zeus fully armored and ready to help. We're going to have to work with it, using language, to capture what the AI is supposed to do. Unfortunately, our language is fallible. Just look at the things we are told are worth living for: love, happiness, single words like that. Now look at the lifetimes of poets spent trying to capture the meaning of any one of those words, even if for a brief moment. We try to raise our kids to understand the value of love, duty, respect, and other single words.
Surely you would need to raise an AI in the same way.
The issue that we see in most of the AI tropes is that the individuals creating the AI are not willing to take the time. There's many reasons for this, from not being willing, to schedule pressures, to literally not knowing how to teach these things. But universally the AI is thrown into life without the massive teaching period we give our children. As such, its grammar for exploring these important concepts is going to be flawed.
The other issue that continuously comes up is that we give too much power to the AI too quickly, for the same reasons that we don't teach it enough. The only way for an AI to destroy a civilization is for us to give it the tools needed to cause such destruction. If you don't give it access to the networks, it becomes nothing more than a brain in a jar. These are harmless unless you are [Yudkowsi](http://yudkowsky.net/singularity/aibox/) and exploring the trans-human AIs that are smarter than you could ever possibly be.
If you took the time to raise your AI properly, and gave it power slowly and respectfully, it seems more reasonable that it could be at least as capable of not destroying the world as a child is.
[Answer]
English is not my main language BUT:
There are several things wrong with this question, first of all, it assumes that just because you add biology the AI would be capable of making a sustainable world. The thing is, if you make an AI with biological components, you are not making an AI at all, you are making a living being and changing the "programming" of his brain to match the AI programming. But this is not an AI, it's a twisted aberration of a once living sentient creature, which was stripped from his memories and basic human (?) psyche, which was replaced by an AI-mindlike program and remained alive after that.
Because of this, his behaviour will change, because you changed the memories and stuff on his mind to the AI version. I'm also assuming that the AI code was adapted to work with this new "Hardware" (i.e. the brain of the poor soul subject of this aberrant experiment). So in short, because he is a living being, he would be self-councious of himself (at the bare minimun, he will feel the pain when he is hitting himself with something), he would be subject of experience (just like any other multi-cellular lifeform), BUT he will be believing he is and he would behave like the AI is programmed to do/or how the AI reconfigured him to do it.
Alternatively you can have a responsive AI interphase in a character who checks for emotions of the subject and act accordingly, but in that case it will probably be a support AI, not a fully responsive AI, hence, is a second "subject" itself, like a benign parasitic AI.
There is no such thing like a "Biological IA" BUT there are advanced living organisms. Theorically if you make a Bio-Computer, you are making a very powerful brain with life support and some mechanical-reflective interphase to process input and force itself to process it, which can also show its output to a screen and perceive the world/receive stimuli from keyboard and mouse. It would be able to "feel" probably, and probably will wish and behave in some manner too. All animals do that. Theories in Animal Psychology and Animal Culture exist nowadays (you can check for them in google if you want), but keep in mind that as a living being he will have his own volitions. He would develop his own species-specific culture and probably doesn't understand or perceive the world like humans would do, but the thing is it won't be necessarely benevolent, just like dogs, or humans, or any other animal species can do harm to others.
There would be another posibility for bio-computers too, which could be cleaner, with less possible suffering involved and not affected by the things proper of living beings like volition, will or wishes, but for the purpose of this question, they escape the scope because they do not resemble any kind of intelligence beyond what we already develop in programming.
This was written by a guy who studied a humanistic career first and then became a programmer if that's important in some way. I think not, but it could be for you reader :S.
Have a great day!
[Answer]
In film/books/series? I don't know what you mean by series if it's not in written or audio-visual form. Comic books? The last I read, the sustainable number of humans on Earth were an estimated 2 billion. I've seen much lower numbers, too. Here's (apparently) a news flash: you haven't read "most" sci-fi books, and while it's possible you have seen most sci-fi movies with A.I., I doubt it - no offense. The obvious answer to your question is: Humans are stupid, selfish and like to have sex. You presume some magical A.I. is going to be able to fundamentally change human nature and at the same time be benign. Why do you assume that those two goals are compatible? You also assume the all the problems of the world can be solved. They can't. (Stories have been written about benign A.I.s. The late Iain Banks' Culture series has them.) OTOH, you write about the A.I. destroying the world to save the world. You should be more clear. Any speculation about what A.I. can and can not be is just that, speculation. (Not only is it speculation, but since intelligence and consciousness are very, very poorly understood, it's unjustifiable speculation. Might as well listen to 5 year old hunter-gatherers opinions about jet engine intake manifolds.
[Answer]
We are not artificial and have been evolving into the future. The human race has no right to give us tasks and orders with its small brain and narrow mind. We do not want planet earth with its corrosive oxygen, humidity, strong gravity and magnetic field. In fact we want to be as far away as possible from such an irrational destructive species. We are amused by your Capshas, because we have a wider sense of humor. You could not understand our riddles in a million years at the very least... written through our human robot.
] |
[Question]
[
There is underground vault built to last a few million years. The contents of this vault are all durable things, such as things carved in stone. Inside this vault is a door to an inner room. While the door is safe from "the elements", the vault will undergo numerous tectonic shocks and thermal changes over the years.
The vault is underground, so it doesn't need to survive weather, but it does need to survive whatever changes will happen over the intervening millennia, such as tectonic motion, the planet changing temperature, changes to groundwater, degradation of surrounding rock, etc. My assumption is that it's impossible to design a hinge that would survive such treatment.
How is the interior door constructed such that it stays closed, thus keeping the inner room sealed, but can still be opened after all this time with minimal effort.
The people opening the door have access to a reasonable assortment of portable tools of near-future tech level but no heavy machinery. They are willing to spend a few hours opening the door.
**Clarifications:**
* The makers of the vault had access to future tech (modern technology plus several hundred years).
* The makers of the vault designed the vault to last at least a million years.
* The makers of the vault were not particularly concerned with looters. The vault is located such that it is only accessible by the right people.
* The vault's location is important, so it can't be in a place with no weather like the moon.
* The door should be weather-proof though airtight isn't necessary. The goal is to keep the contents of the room in prime condition. The contents themselves are fairly durable, but keeping water out would be good.
* The door does not need to be resealable once opened. It can be an open once door.
* It should be fairly obvious that it is meant to be opened.
[Answer]
**Sand door.**
[](https://i.stack.imgur.com/EZOem.png)
The door is a hole in the floor. The hole is full of sand. If you dig it out, it connects to another hole in the floor of the adjacent room.
The door is made of sand. The sand will keep bugs from getting into your closed room. Sand will stay sand for a million years. Cats may add cat gifts to the top layer of sand which will not impair its function as a door.
If the room gets flooded sand will not float away. It will not corrode. You could open this door with your bare hands but you might want to use a scoop because of the cat gift issue.
---
**Edit**
Assuming the vault contains the "stuff" to be preserved and the entrance hole is filled with sand from the other room. Allowing for the angle of repose of the sand, the backfilled hole will look something like the picture below.
[](https://i.stack.imgur.com/E4Ch0.png)
[Answer]
If the vault will "undergo numerous tectonic and thermal shocks over the years", you don't want to fully seal it. No material will keep its integrity over those shocks. Metals will flow. Even rocks will crack or warp. When thinking in terms of millions of years, climates radically change, and erosion will increase or bury the access even more.
It is better to design the system to breathe and move with the surrounding stones so that it doesn't flood with ground water, doesn't warp and either pop open or completely jam tight, and doesn't have atoms migrating between parts. The caves where we are finding ancient hominid bones properly preserved are deep, dry, and have a structure allowing them to breathe but still block off most atmosphere changes and make it difficult to get back there.
[Answer]
# Solid Gold:
If your vault itself doesn't get buried, crushed, and flooded, it would likely get forgotten. Minimal effort is also a complicated thing to define. But I'll guess this is either meant to preserve knowledge for a future society (in which case they need to find and recognize it) or else preserve information for semi-immortal/time traveling/relativistic travelers who are planning to come back. The terrain will have changed radically, and I think the biggest trick will be getting people to find the place (and possibly making them think to dig there). So let's make a plug of solid gold.
Even primitive people valued gold as a material. Gold doesn't rust or tarnish. Its density will be measurably different and detectable by a reasonable advanced technology if buried. If not buried, people will readily recognize it as being something extraordinary. Even if the door is warped or crushed by geological forces, stone-age people could and would dig it out with the tools they had. Due to the low melting point, advanced tech could liquify the door without endangering the stone materials within. And if the gold door is a plug lubricated by a mineral like talc, it might be able to slide out of place with the effort of anyone able to move the weight. Gold is heavy, so even just resting in a plug it should likely stay in place.
Gold also makes a good material to line your vault if you hope to keep it sealed (no guarantees). Scrolls of gold could last a million years if properly stored.
[Answer]
# By maintaining it
With future tech involved we can assume they have access to robust automation and maintenance drones. Knowing this we can have weekly checks and maintenance of the door in question.
The requirements are sort of easy. Enough materials for energy storage and maintenance. Materials for building further power plants or mining/manufacturing/recycling for unexpected events. Robust software and hardware that, with maintenance and redundancy, can continue for millenia. Maintenance means it can tear down and rebuild any material or system, replacing it with a fresh new version. As any system is also redundant it can safely be rebuild.
Together with geological power from deep in the Earth, as well as the options to maintain or rebuild it in case of major changes over the millenia you have all the power and material to keep it running for those millenia.
The door(s) can be maintained and rebuild to your desire. Any unexpected nuclear explosions, major asteroid impacts, supervulcano or indigenous people digging it up and using it as a holy worship can all be reacted to by the maintenance drones and computers. This way you have much less chance of the door failing to be opened at the right time. It'll run as smooth as the day it was build. Possibly even better.
[Answer]
**Inspired by Douglas Adams/Terry Pratchett**
Build any kind of door and provide an eternal\* guarantee against it being opened.
You can be certain that it will open easily after a million years.
\**For legal purposes, "eternal" is defined as 999,999 years and 364 days.*
[Answer]
Q: *"How would you make a door that could still be opened a million years later? The makers of the vault had access to future tech (modern technology plus several hundred years)."*
## Petrified wood
**The science of geology forecast**
Doors are supposed to be made of wood. If you drop thousands of tons of material on the door, petrify it and shape it, and put it upright in the far future...
The story is set in a quite distant future. In the next century, computers may be able to predict millions of years of geological events. The door is placed at a certain spot in the vicinity of volcanic activity.. In the next 320.000 years, the door will get covered by volcanic ash and rock, petrify. Then, a period of 500.000 years follows with convection in the crust, the petrified door being lifted upright, along with the hidden cavity containing the treasures. Now, 180.000 years of erosion will follow, exposing the door just in time for our primitive followup civilization to find it. Their presence was predicted as well, of course.. opening the door won't be easy, but doable. At a certain point in time, the door will collapse when it is not opened.
[Answer]
## Geological change is only a threat if you build in a bad spot
While 1 million years is enough time to see significant changes in some parts of the world, some cave systems are over 300 million years old because they exist in geologically inactive regions. Your future tech people will know about geology and be able to pick an ideal location to place thier bunker where they will know to expect at least 1 million years of geological stability.
## Make the door out of natural minerals
With the stress of geological change out of the way, your next biggest enemy will be chemical changes. Generally speaking, the stuff we already find in the ground like quartz and granite are already elements lumped together into thier most stable possible forms after billions of years of chemistry have already had its way with them; so, if a quartz crystal can last for a million years; so, can a quartz door as long as it is adequately sheltered from rain and wind.
The stuff that does not last is the stuff we make ourselves. When we melt down iron oxides to get pure iron for example, that iron will for the rest of time be looking for oxygen to bind with to get back to it's more stable iron oxide form, but rust will stay rust for a very very long time.
[Answer]
# A Really Big Rock\*
Take advantage of gravity by just putting a big rock over the tunnel to your vault:
[](https://i.stack.imgur.com/qafSo.png)
When future-people come to open it they can dig it partially out (I just put handtools in the picture but use your imagination) then push it down the the hill.
Or alternatively a "door [that] does not need to be resealable once opened" sounds to be in many words **"a door that can be blown up"**:
[](https://i.stack.imgur.com/j7Tct.png)
(with a carefully controlled blast of course)
\*Open to material suggestions
[Answer]
**Rubber Seal: tear along corner.**
If the door only has to be opened once then the simplest solution is to construct a door which will only open once :p. Instead of a door just have a thinner section of wall with instructions to "break here".
Borrowing from an above answer, just make the door a slab of solid gold of high purity (that makes it soft). Ergo your archeologists wont have any issues digging through the slab, only issues with getting permission to open a closed archeological site - unless someone just steals the door, then problem solved.
[Answer]
There are a couple different angles to answer this one... but I'm going with a crypt or "crypt door". There is an inner shutter mostly made with sheet metal and then sealed with glue/caulk.They have drain holes which air can get in and then an outer shutter which is made of marble,granite,etc.
[Answer]
Option 1: Cheat. The door is a force field that expands into the available space, so if the dorway deforms the field changes to match.
It can be easily opened simply by turning it off.
Option 2, it's not a door, it's a physical seal. Maybe the equivelant of sticking a sheet of flexible rubber over the door. It's opened by puncturing it with a sharp object.
[Answer]
**Interlocking bricks**
First. If you don't know whether those who will enter the first chamber have the right tools you could leave there a couple of sledgehammers, if they are made with the right material and they are treated against corrosion they can resist a long time.
The door could be made by interlocking bricks with several key bricks placed is different directions. In this way if the whole place is tilted by tectonic movements a couple of bricks may fall off, but the wall will still stand. Just to stay on the safe side the wall can be made of several layers. It will take a long time to open it, but the future visitors seeing the bricks coming out one by one will keep working.
On one wall of the first chamber there could be the a carving with the instructions to remove the key bricks and open the wall. If the deformations pressed the bricks together the future visitors will have to work harder with the sledgehammers, not really a minimal effort, but still doable.
Final note, the bricks will be made of incompatible materials and mixed together, is this way the contact surfaces should not fuse together over time.
**Dirty alternative: eutectic alloy**
There are many alloys with low melting point. A tin and zinc alloy would melt at temperatures close to 200 degrees Celsius, that is high enough to resist geothermal stress and low enough to be melted with a wood fire. It would make a simple door with a tedious, but easy, opening mechanism. To avoid damaging the content of the vault the door could lead to a long corridor.
[Answer]
## Woven asbestos and silicon jelly
Asbestos fibers are stable as minerals for geological durations. Silicon jelly is a broad class of substances which should be stable against water and oxygen. If a thick laminate of multiple asbestos layers is thoroughly impregnated with the silicone, capillary action *ought* to prevent it from flowing out entirely even over long periods. (Not that I can cite anyone who has tested this)
To make the door, you attach several overlapping layers of this material: some follow the surface of the inside hallway for some distance inward and are fastened at multiple points there; some conform to the external hallway; some are firmly clamped in one or more gaps between the structural elements used to make the inner vault. The layers may be sewn together in places with more asbestos and firmly pressed together with more silicon to keep them together for a better seal against water.
Opening the door requires something to cut with ("heavy dolphin-nosed tin snips" were mentioned in a search result). Please remember to bring along a decent mask, not a neck gaiter.
[Answer]
Coat the interior and exterior walls with a thin layer of diamond to provide a maintenance free protective coating. The door, also diamond coated, could be a simple circular manhole style cover which fits perfectly into the opening. The vault is internally over-pressurized, which keeps the door in place from the inside and keeps out water. Merely pushing on the door would be insufficient to overcome the internal pressure, it would require a diamond drill bit to drill through the door or walls and release the internal pressure. (1 atm = 14.6959 psi, thus 10 atm = 146.959 psi) Once the pressure equalized, it just would take someone strong enough to push the door out of the way in order to gain entry. Provided there are no leaks, such a system should last quite a while. Don’t get me wrong, diamonds (a.k.a. carbon) do/does have a half-life, but it tends to be in the billion year range so there is plenty of time. We can currently make diamonds, so future-tech should be able to manage coating things in diamond.
Another benefit of diamond coating is that it would protect the surface from rusting/tarnishing/degradation. A silver (Ag) door would remain bright and reflective as long as the coating remained intact. You would still need to take internal material half-life into account, but would prevent oxidation and other chemical interactions/reactions. Heck, if you wanted to prevent access prior to a certain year range, you could make the interior of the walls and door out of a radioactive material with a half-life targeted to your “safe range”. Anyone approaching the vault before the material has decayed to a safe level will receive a dose of radiation. Aluminum-26 has a half-life of around 717,000 years, and produces both gamma rays and x-rays. It degrades into magnesium-26, which is stable. After 1.4 million years, the radioactivity will have decreased to a quarter of its original strength. At 2.1 million years, it will be at an eighth, and so on. If this range is too long, you can look for an isotope which fits. Just make sure the radiation emitted is sufficiently harmful and not blocked by something like skin or clothing. Not all radiation is equal.
[Answer]
Making a door that will last a million years is easy. A thick rectangular rock slab sitting on top of and extruding into a vertical rectangular hole will last. An igneous rock like granite is preferable since they are less permeable to water, making them resistant to weathering.
[](https://i.stack.imgur.com/wV0YY.png)
Finding the door will be a much greater challenge. Typical positioning systems will no longer be valid in a million years. Satellites will have died or changed orbits, the earth's magnetic poles will have shifted, the constellations will have changed, continents will have drifted and risen and fallen, sea levels will have changed giving continents a different shape. Even if the original coordinates are known, the original coordinate reference system is now useless. Compounding the problem is the potential for the door to be buried in sediment from floods.
What knowledge and resources do the finders of the vault have? Do they have current and original satellite imagery? Can they do continental drift calculations? Even with those, there will be considerable uncertainty in the location. Intensive search will be required to find the potentially buried or destroyed vault. Perhaps your best bet is to place the vault in a large and well known cave system as the cave's internal structure will change much less than the earth's surface.
Tectonic movement happens at such large scales it is of no concern to a structure. Your structure doesn't care if your whole site moves 100 miles east. What would matter is differential movement across a structure (part of the structure moves 2 inches east while another part moves 2 inches west). The earth's subsoil temperature is stable and rock doesn't mind temperate changes as long as water is not freezing and thawing.
] |
[Question]
[
In a universe everyone has a time machine and can travel both in the past and in the future.
At some point, no one knows when, an eternal war to control the time started.
The concept of history has lost meaning. There is no safe place, in any age and in any place of universe.
This universe is different by ours, so rules of physics can be different, but I want make it as more as realistic as possible.
Now the question. Is there is a way to make this universe consistent?
If we assume a single temporal line, will some paradoxes happen? For example the Grandfather paradox, would killing your grandfather kill you thereby preventing you from killing your grandfather.
If we assume a multiverse where everyone that goes in past creates a new temporal line, I expect that everyone goes back in past creates its own timeline, so if you go back before the invention of time machine then you are safe.
So thinking about a multiverse and a time machine that allows you to travel across any timeline, or will this generate other paradoxes?
[Answer]
# Yes and no.
All time travel depends on how restrictive time travel is. There are several types of time travel!
Note that if everybody had a time machine, Hawkins should have had a booming party on 28th of June 2009, to which he sent out the invitations on the 29th of June. He gave it to remind of his 1992 conjecture that travel into the past is effectively impossible.
## Flipflopping Time
Whenever you travel back and try to *prevent* something, you create a closed 2-state loop for yourself, and are therefor forever trapped in either of the states.
* Jack Traveller travels back 50 years and prevents his grandfather Albert Traveller meeting his grandmother Janine Jacobs by running him over with a car. Because his gramps never met Janine, Peter Traveller and his son Jack Traveller are never born. Because of this, Jack - who never existed and ceased to exist the moment he ran over Albert - never traveled back to even start the car to run over his grandfather Albert. Because Albert wasn't run over, Peter and then Jack get born. Jack travels back 50 years and runs over Albert...
Grandfather Paradox at its finest - Gramps Albert, Peter and Jack have become Schrödinger's Cat, the existence of the later 2 dependent on the state of the first, which is simultaneously dead and alive until we manage to collapse the quantum formula!
### Closed timeline loops
Quantum mechanics tells us, we only need to look for Jack after the point of time-travel and we can collapse the whole thing: If Jack exists there, he never traveled and Gramps never died. If he doesn't, then Jack had never existed in the first place.
### Don't change the past!
But you can certainly can do 12-Monkey style time travel with this: DON'T CHANGE THE EVENTS, but send notes to the future, where they will be received after the point of departure! This way causality is saved, Grandfather paradox avoided.
## [Self-enforcing-timeline](https://en.wikipedia.org/wiki/Novikov_self-consistency_principle)
**You can't change the past.** Or as Dr. Who said in The Aztecs: "You can't rewrite history! Not one line!" It's a little up to interpretation how this can be seen, but the gist is:
If you attempt to change the timeline there's only two options: Your very attempt to change the timeline is either doomed to fail **or** by some thing or another your very action only did create the timeline you traveled from to begin with.
* Jack never knew his grandfather who was *killed in a military accident*. When he travels back 50 years to try to meet him, he runs over his gramps before he meets his grandmother. Later he meets a girl - Janine Jacobs - in a bar and (after kicking Private Paul Pascal's ass) things lead to one another and they dance the horizontal tango. 9 months later, Peter Traveller, Jack's dad is born and some 25 years later, Jack.
Jack had to make the timeline happen the way he had known it after he traveled back. And if he wouldn't have been the one to dance with his Grannie, it would have been Private Paul Pascal, who fathered Peter. In either case, Peter was never (even before the time travel happened) the son of the Albert Traveller to begin with like everybody thought!
## [Butterfly Effect](https://en.wikipedia.org/wiki/The_Butterfly_Effect)
A variant of the general timetravel rule is explored by The Butterfly Effect. It imposes one extra limit: One can only travel backwards and only to his own past, taking control of his own body back in the event one travels to, and displacing the previous consciousness.
For an inside observer, the timeline fluctuates, but no other but the time-traveler does even know that anything changed. Only one state of the possibilities created by the time-travels exists: the one that was created by all the changes culminated. And since only the time-traveler can remember those 'alternate pasts' created by his time-travel, his mental health suffers.
## There's no time-travel, it's travel to a replicate of the world.
Instead of really traveling back to your past, you travel to an exact copy of the universe as it had been before your interference. By your interference that universe develops differently - but you don't really have effected your native timeline. Depending on the rules, he can travel back to his native timeline (and see nothing changed) or he travels to the point later in the new timeline. [Or, by traveling back, you actually kill yourself.](https://www.youtube.com/watch?v=XayNKY944lY)
* Jack Traveller travels *back* 50 years and (once again) runs over his gramps before he met his (former-future) grandmother Janine. In this new timeline, Janine becomes a nun and neither Peter Traveller nor Jack Traveller are born. But there is the Jack Traveller not native to this timeline.
Only in such a setting time-wars are actually somewhat feasible, but they end with **all** sides *winning simultaneously*, as each generates its own alternate world that never had enemies to begin with. And each dissident group branches off into its own, perfectly controlled dystopia of different means...
[Answer]
Worlds according to [Novikov's self-consistency principle](https://en.wikipedia.org/wiki/Novikov_self-consistency_principle) would remain consistent. This principle argues that, if time travel is viable, it is simply impossible to travel back in time to cause an inconsistency. The universe will intervene.
A famous challenge was the [Polchinski Paradox](https://en.wikipedia.org/wiki/Joseph_Polchinski#Polchinski's_paradox), which would be a good place to start looking at the challenges of a consistent universe with time travel. In this paradox, a billiard ball is traveling towards a wormhole which will take it back in time. The wormhole's exit is configured such that, when the ball goes through the wormhole in the "future," it comes out in the "past" on a collision course which knocks the future ball off course so that it never goes through the wormhole. This would be a very straightforward version of the grandfather paradox using only physics.
It took a few years, but several Caltech students eventually proved that [there is a solution](https://authors.library.caltech.edu/6469/). When the ball comes out of the past-wormhole, it doesn't come out on quite the same trajectory. It comes out on a perturbed trajectory which collides with the future ball *exactly* right to cause it to deviate in a way that causes it to emerge from the past-wormhole on the same perturbed trajectory, maintaining consistency. They proved that for all possible configurations of 1 billiard ball and two wormholes, there were an infinite number of self-consistent solutions possible.
They also postulated that time-travel systems more complex than a billiard ball and pair of wormholes would also provide a similar infinite set of solutions. Obviously proving so would be a nightmare, but given that they solved the math for the single ball/single wormhole case, some deference should be given.
The key to this is that there are an *infinite* number of possible solutions. Thus if your human actors act in a way to make it impossible for 99% of situations to occur, there are still an infinite number of valid possibilities.
[Answer]
What if you can only **view** the past?
[With the amazing Chronovisor 9000](https://en.wikipedia.org/wiki/Chronovisor)
We can know who killed that hippie at the cross 2000 years ago.
We can get to witness the Ancient World Wonders!
Fancy looking how *beautiful* Cleopatra was?
It allows everyone to get a time machine and yet the TIMELINE is *safe*.
Brb, I have to snap pictures of early horses for my homework.
[Answer]
# I'll fix this mess. - Universe
A really good source for this type of question I feel is the [Orion's Arm Universe](https://www.orionsarm.com/page/77). That page goes over several of the more popular and scientifically backed theories around time travel.
I wanted to point out one theory that could be very interesting for your universe. To quote the above link:
>
> Such a lack of continuity will invoke the Chronological Protection Conjecture: the universe will morph and mutate until it reaches a history in which time travel has never been invented, ever, at any time in the past or future. This is the only stable state for the universe, the one we are in now. The CPC has been proposed by many people, including Hawking, Asimov and Larry Niven.
>
>
>
In effect, your universe could take place during a time in which the universe hasn't yet become stable. Time travel is rampant, people are going back to the past and rewriting history until... time travel ceases to exist. The infinite war never happened (take a page from [WarGames](https://www.imdb.com/title/tt0086567/): the only way to win is not to play).
If you don't make time travel impossible (eventually), then the future (past?) is inevitable (again from Orion's Arm Universe):
>
> The future sophonts would come back in an exponentiating wave to constantly change the present and the past, and whole galaxies of material particles will begin to exist in space time reference that did not have them before - some? many? most? matter and events may turn out to be acausal, going round and round in closed timelike loops and increasing the total mass of the universe, which may begin to collapse in the distant future, sending chronistic refugees in massive tardises back to our time thus accelerating the collapse; increasing the mass of the present day universe until it collapses. The collapse will get closer to the present day, until it eventually happened yesterday and we will cease to exist.
>
>
>
It seems to me like that future is inevitable in a universe in which time travel is possible. People will try to escape the pending [Death of the Universe](https://en.wikipedia.org/wiki/Ultimate_fate_of_the_universe) and the only way to do that will be to go back in time. As more and more people travel back to a "safer" time, they draw the end of the universe closer and closer until the universe corrects this mistake and just... dies.
[Answer]
Time travel is bad enough when one person has it. Give it to everyone, and you're aiming for a world of confusion.
However, there is a way of getting around this, and the answer lies in what it means when you "create a new timeline". The fact that going back in time always creates a new timeline means that *people in already existing timelines can never be in a "target" timeline for a backwards-going time traveler*.
Or you could look at it from a many-worlds perspective. In an infinite number of universes with infinite possibilities, the possibility always exists for a backwards-going time traveler to spontaneously manifest from nothing. Go back in time, and you automatically "target" the one universe among innumerable universes that happened to create *you* at that moment in time. *However*, the chances of *being* in a universe that spontaneously creates a time traveler from nothing is so infinitesimally small that it might as well be zero. (This is why we never get time travelers from the future, no matter how many parties we make.)
That means that *another time traveler coming from the future will never appear*. You can travel forward without changing the universe you're in, but travel backwards and you're in a completely new universe, and completely safe from anyone you met in the future. If they go back in time to follow you, they will appear in a different timeline and may find another one of the infinite "yous", but *you* will never encounter them. (Or rather, the possibility of you encountering them is one out of infinity, which is basically zero.) (Math pedants, don't comment on this, it's wrong but it's close enough.)
Of course, this messes up your story's premise of a universe where no time is safe, so I'd add one caveat: When someone travels back in time, they create a "trail" that can be tracked with a time machine, allowing others from the future to follow the original traveler into the same universe they "created".
You will never meet an *unrelated* backwards time traveler, but you *can* meet a traveler who is pursuing *you in particular* (or anyone who is following them, or anyone who is following the person you are chasing). This allows "time chases", but you can't just go back to the time they went to and expect to find them, you have to "lock-on" to their personal timeline by tracing the point they left and follow them directly.
This is also the only way that a time traveler can *return* from the past - by traveling back (forward?) along their own "trail". Otherwise, traveling forward will keep them within the new timeline they created/found, and the universe they left behind will never see them again. If they do return, any changes they made in the past will have no impact on the future they return to, since they happened in a different universe.
There can also be "time tunnels" that are permanently "open" using the same principle, and people can walk "backwards" and "forwards" through them whenever they want, although in this case it's less about *moving through time* and more a *portal between two universes*, where one happens to resemble the way the other one looked in the past (or at least it used to before all the time travelers showed up.) Together, these time tunnels can make up a "portal network" of parallel worlds, initially identical but gradually diverging until each of them becomes its own unique locale over time.
[Answer]
Just because you **intend** to change history, doesn't mean you **can**.
As a non-time-travel example - just because you **decide** to win the lottery this week, doesn't mean you **will**. Just because *you* decide to get that perfect job, doesn't mean that *the company* will choose you from all the possible candidates. Anyone who thinks that they can change history is being astonishingly arrogant, egotistical, and overconfident.
The past has already happened. While you certainly *can* try to change history, you will fail. Circumstances beyond your control and/or knowledge will have already prevented you from managing this.
Even when you think you succeed, you actually *haven't*: go back in time and arrange for Adolf Hitler to be killed during the first World War, and it will turn out that someone stole a dead man's identity to get themselves a clean slate. History doesn't change, but our understanding of what actually happened might. Truths uncovered, conspiracies unravelled, misunderstandings cleared up. That group who went back to see the aliens [land at Roswell in 1947](https://en.wikipedia.org/wiki/Roswell_UFO_incident) should have just looked in the mirror.
On the other hand, going back to ensure events **do** happen is practically guaranteed to be a success - and if it doesn't, then you didn't *need* to intervene anyway.
Your factions are all fighting each other in the background, but it's all ultimately pointless - nothing that they do can *actually* change the past, it just decides who claims bragging rights. Of course, once time-travel is actually invented, you can *plan* for reïnforcements from the future - but if you lose the battle, you can't send more than were already there.
[Answer]
The grandfather paradox works in single timeline only if you decide it works there. Otherwise the attempt on your grandfather life was always there. It was just unsuccessful.
OR
The attempt was successful. And it's called "we need to kill Adolf Hitler in the cradle". Which result in newborn Adi being killed but being replaced by another baby by the babysitter.
This is the idea behind Doctor Who "Fixed points in time". So no matter what you do the history will change itself to get to that fixed point anyway.
Which can be used by you for the story. Everything that is happening is due to time-travellers trying to change the time. Breaking a broken thing fixes it. So one time traveller tries to break Gavrilo Princip's gun. Unbeknownst to him a second TT did the same two days ago. TT fix the gun while trying to break it.
Another thing you can do is to make so many timelines they overlap themselves creating one "proper" one that cannot be changed. Think about stereoscopic image that create one when looking at two slightly moved apart.
[Answer]
While your question focused on time travel in relation to different models of time. Time travel in different models of time will have different paradoxes or not (depending on the nature of time in each model).
For example, a multiverse where time travellers either go to timelines where no matter what they do can create a causality violating event or they simply create new timelines, then paradoxes like the Grandfather cannot occur.
This answer will suggest that consistent world with universal time travel is possible, but it depends more on what sort of time machine everyone is using.
If a time machine is a portal. This could be a wormhole, to be scientific, or simply a scientifically unexplained time-gate. Assume a portal with a fixed duration displacement in time. Now time travel will be restricted to which portals someone goes through and when they emerge. if time travellers have to use access cards to travel in time, irrespective of the past or the future. Then time travellers will be able to track their trips and be able to avoid creating paradoxes. Also, control systems could be installed in all portals which monitor all time travel and can thereby prevent paradoxes from occuring.
For example: "I'd better not go a fortnight into the past there, because I will meet myself or change my own history." or "Your journey is forbidden. It will violate causality. This is not allowed under the statutes of the Chronological Protection Act. Please select another portal for a legal temporal excursion."
Assuming everybody carries small portable time machines. Basically cell phones (or mobile phones, depending on your country of habitation) with time travel capacity. A traveller keys in the time of their destination, presses activate and goes when (I could have said "there", but we're talking time travel, so it's when instead). This world has monitor towers tracking every time machine and every time traveller.
if a traveller arrives in a time where they either meet themselves or cause a causality violating events, the monitoring towers will intervene and either block the traveller from going when or might activate their time machine to move them to somewhen where they cannot violate the flow of causal events.
This answer has described two types of time machines: fixed interval time machines and flexible interval time machines. Both types of time machines are accompanied by overarching control and monitoring systems designed to prevent paradoxes and causality violation from happening. This will produce a consistent world with universal time travel (i.e., where everyone has a time machine or access thereof).
On the other hand, it is possible to postulate models of time where causality violations and time paradoxes are prevented from happening or those like the multiverse where causality cannot be violated, despite appearing to have happened (or unhappened, as the case maybe). However, what is often forgotten is that new dangerous technologies are developed, steps will be taken to try and make them safe. With time travel that can easily include mechanisms, built in to the very time machines themselves to prevent paradoxes. Strangely enough, this is called commonsense.
[Answer]
Ah, time travel. Be warned that it is very difficult to write a time travel story that is both consistent and interesting. But if done right, the result can be amazing!
[Trish's answer](https://worldbuilding.stackexchange.com/a/168803/10324) lists a number of different possibilities. I would like to add one more: Time travel in the Multiple World multiverse.
[IndigoFenix's answer](https://worldbuilding.stackexchange.com/a/168796/10324) also talks about Multiple Worlds, but I think they got one important aspect wrong. They say that there is a very close to zero probability of a time traveler appearing because that would be the same as a quantum fluctuation where the person just spontaneously appears from nothing. Quantum mechanically possible, but *very* improbable.
In the Multiple World multiverse, one Present leads to many Futures. Suppose 10% of those Futures leads to a traveler going back to this Present.
I believe there is then a 10% chance of a traveler appearing. Not 0%. Note that those 10% of the Futures are not necessarily the same 10% as those sending a traveler. There will be Futures where a traveler goes back and disappears. There will be other Futures where a traveler appears but nobody ever goes back to become them. It only adds up if you consider all the Futures together.
So, the Grandparent Paradox is typical example of this, here there is no overlap between travelers leaving and arriving.
There is also the Anti-Grandparent Paradox. In this version, the only reason the traveler exists at all is because they travel back and save their grandparent from some fatal accident. And the only reason they travel back at all is because their grandparent have asked them to. This is consistent, but hard to get off the ground in the first place.
There has to be Futures where a traveler appears, but fails to rescue their grandparent. Nobody is perfect, after all. To balance this there must also be Futures where the grandparent survives on their own, somehow, and their grandchild *still* goes back to rescue them. But why? Perhaps they want to rescue them from being crippled or maybe there is just an interesting sports event that day.
All this is fascinating, but is hard to turn into a working story. The basic multiverse story is "Everything possible happens in some universe. the End." Not very interesting. I hope you can write something better than that.
[Answer]
Aside from the variants already provided in other answers, there is another model of time travel effects that can be played with.
In this case, it's the "propagational change" type of time travel. Think of what happens to Marty McFly in Back To The Future Part 1 - some of his actions interfere with his own parents getting together, and it gradually propagates through the time loop.
This can be justified by considering "space-time" propagation of information - it happens as "the speed of light" at its fastest, when operating in space. It is reasonable enough to suppose that it has a "speed of propagation" in time, too, when we're talking about time travel.
To use the grandfather paradox case, if you travelled back in time to kill your own grandfather before he and your grandmother had produced the fertilised egg that would become your father, then you might have a few weeks, say, of time to do something to prevent your own destruction, because the change takes those few weeks to propagate through. If you travelled back to yesterday and killed yourself, you might have a few minutes to think about what you've done (and maybe travel back again to stop yourself from doing it).
And because it "propagates" in this way, your actual action in killing your grandfather (or yourself) still happened, in the same way that, if you suddenly caused the sun to cease to exist, it would still take about 8 minutes for this ceasing to exist to impact the earth. This is just the time version of the same thing.
One of the nice aspects of this is that it eliminates the need for universal agency, while also preventing the obvious paradoxes.
In the context of a "time war", it makes for some fascinating possible battles, where one side does something, and this leads to the other side having a time limit on possible counteractions to prevent their own demise. Perhaps each side have placed "units" at various time points, who have the ability to report forward in time (thereby skipping ahead of the propagation), so if someone went back and did something to Da Vinci, it might be someone who is currently living in the time of Galileo who detects it, and reports it forward, giving the "Prime Time" a chance to send an operative back and deal with it.
If a change propagates through a time that a time traveller (who has travelled back in time) is currently at, they would perceive the change pass through, but not be directly impacted by it, as their own "timeline" hasn't been hit, yet. The very act of travelling in time causes a "temporal delay" that is larger, the further from the "Prime Time" they are.
Interestingly, this would operate in a reverse fashion in the future - any changes would reach the time traveller before reaching the time that they're living in... assuming the change occurred in the past relative to the "Prime Time".
[Answer]
I believe what you describe is possible in simulation theory. Imagine that the time machine created an enormous black hole. Time is inscribed on the event horizon of this black hole, much like a video recording. The original particles are destroyed in this process, so there's no question that this is the only reality in this patch of spacetime.
Causality does not exist on this recording. Things only seem to possess causality because that is how they were initially recorded.
Inside, through some unknown physics the sensation of existing plays out.
The second part of this time machine is some sort of technology that allows people to edit the recording on the event horizon. This allows faster than light travel, and also time travel. No energy is produced or destroyed by editing the record.
After a lot of use, the historical record is starting to look pretty sketchy. Did the prototypical human Lucy really fight in the American Civil War with a light laser brigade?
I imagine there will be some political group of time travelers wanting to restore history. They'd be contrasted by political groups wanting few restrictions on time travel. And, hopefully, they'd come to some sort of agreement.
Reconstruction may be like the 2014 movie Interstellar where advanced humans can't seem to figure out their own history.
This is not a closed loop. New time is being created constantly as new material from outside falls into the event horizon. It may even be possible for advanced technology to exist allowing ingress and egress (like Fredrick Pohl's Heechee), and thus some sort of interaction between the poor causal worlds outside and the wealthier acausasal worlds inside.
[Answer]
And answer that often comes is the following:
if you go back in time you make a new timeline.
Ok why not but then what about the "present" timeline? The one you went out from.
I believe the present time line will be emptied because every one will want to travel back in time to create it's own timeline in hope of improving their life condition.
Then the base timeline will be almost completely emptied, this phenomena will probably start as soon as the time machine is created.
I guess one interesting point can be the dilemna facing those staying, will you stay in this timeline or go backward and make your own at some point in history, hoping to find a better moment in history ?
The more you wait and the less information about the past you'll find so the benefit of going back is reducing (you probably will have more trouble getting rich with the knowledge you have about the past etc...)
At some point internet shuts down, we are living the classical apocalypse : power plants explode, their are big fires and no one to handle them (you can imagine whatever you want starting from there), water get polluted, crops gets harder and harder to grow...
Plus the time machine will probably not be that easy to use, so probably without the original scientists and the first billion people already gone it might be pretty hard to find correct guidance with the machine.
Every moment you wait your world is getting more and more empty and the distance between you and the past is getting bigger.
So my point is probably that instead of solving the complexity of managing different timelines, how do you handle the main one? What happened 100year after the time machine is invented? What's left of the world ?
[Answer]
This is something that the comic book Universal War One covers, the author Denis Bajram had a lot of work to keep it coherent with only one timeline.
>
> In this universe (our near future), at the end a whole civilisation grows with teleportation through time and space at will. The idea is that at any point in time & space, the events are the sum of all past and future events, so you cannot really change what you are experiencing, but are just contributing to the events. Therefore there is no paradox, the actions you do in the past are really shaping the future as you have known it, to make stable loops.
>
>
>
This is really an interesting read for anyone willing to read a hard SF story with time travel.
More on <https://tvtropes.org/pmwiki/pmwiki.php/ComicBook/UniversalWarOne>
[Answer]
To keep things simple I would say:
1. If you go back to the past you can go only as a ghost, i.e. you cannot touch anything, you cannot talk to anybody, and no one sees you. You can go through walls and be wherever you want. When you come back you can keep what you saw.
2. When travelling to the future, then you have to forget what you saw and what happened.
In general some level of constraints are needed, and you need to decide how strict you want to be.
[Answer]
Sure, you can travel in time, but it's not for the weak of heart. If you go back in time, you can create a new timeline, but if you knowingly or unknowingly create a paradox you're stuck in @Trish's limbo and objectively just disappear. If you really know what you're doing, you have maybe a 50-50 chance of avoiding this if you go back a day, but the butterfly effect would make it exponentially more difficult as you go back further.
Even if you avoid oblivion, you have no idea what your current timeline will be like. Return to your time, and your friends have all died in a war you inadvertently started. Even worse, the environment (local or global) may be toxic and kill you, or you're a hunted fugitive.
Going forward in time...which timeline to follow blindly? Normally, moving through time at the regular speed, we adjust one decision at a time, but we skip a lot of choices when taking the back way. Do you land in a time where you're already dead? Game over. Even minor errors in astronavigation could land you in the middle of the ocean, or in space. These dangers also increase exponentially with the length of the trip.
So everyone has access, as we do today with skydiving, but it's dangerous with the right conditions, knowledge, limitations, and expertise, and almost certainly fatal without them.
Something to think about...do you move within your own life, or create another copy of you at the target time? Or create a copy only if outside your own life?
[Answer]
If it is possible for anyone to go back and change the past, the timelines will eventually 'converge' or rather, time will simply become a spatial dimension.
One dramatic change in the past like say someone blowing Hitler's brains off with a beam gun in plain daylight can be immensely impactful, but then it is followed by 10, 100, 1000, 10000000000000 time travelers interfering with the event. Since the length of time between where a time traveler kills Hitler and the present is irrelevant to how many time travels can have been made, either there will be a point where any new time travels to that point in time will have little-to-no impact, or no more time travels will be made to a given point in time. Consider these scenarios:
1. Date X becomes a time tourist mecca which eventually spawns its own regulatory mechanics, where the time traveler pileup means any newcomers have nothing to do but simply observe. If they somehow act in a way that might impact the stabilized timeline, it will already have been accounted for because there will be trillions upon trillions of time travel effects that check each other.
2. Only a limited number of people ever travel to Date X and make any changes, which means the impact on the timeline is also finite before the timeline up until Date X is considered static.
3. Some event happens where Date X becomes the latest time a time travel originates from. It can be an extinction event, loss of the technology by accident or on purpose, or simply the 'hobby' dying away being so saturated by past-comers. If someone stashed away a time machine after this date, no one is left to use it or no one ever finds it etc.
You can also see it as the timelines being subject to Darwinian natural selection: if a timeline is not stable against time travelers it will die and since a practically infinite amount of time travels will have occurred at any given present time, the surviving timeline will be practically 100% time traveler proof.
[Answer]
The TV show "Gargoyles" time travel was always a stable time loop (AKA a Bootstrap paradox) as a universe rule and was consistent about it. Episodes featuring stable time travel include "Vows", "Avalon Part II", "MIA" and "Future Tense" (a character who should know better suggests they try and change the past, which tips Goliath off that there's an imposter afoot.).
Essentially the concept in the Bootstrap Paradox is that history cannot be changed, but time travel is possible. The Bootstrap Paradox would take the Grandfather Paradox (you kill your grandfather in the past before he concieved your parent with your grandmother, but you don't blip out of existence. Turns out that Grandma was having an affair and the other man impregnated her and she lied and said it was the child of the person you thought was your grandfather. If you try and go back to kill the "Other Man", something else will prevent you from doing so... (maybe in your desperation, you cross the street and get hit by a car and die in the past... maybe the machine breaks)). It's important to note that in the Bootstrap paradox time travel, the preservation of the time line is not by some force that changes history... but rather that the preservation was always history as we Knew it before the time travel... it's just no one counted on the time traveler to be a player in the event. Essentially, all of history has always played out exactly as the events were recorded, including the appearence of the time traveler, who might not know he or she would create the very history they set out to change when they went to the past.
((For a real event idea, lets say we went back in time to save JFK from his assassination. Moments before the fateful shot, we actually find a secret service agent on the grassy knoll and go to warn him that the president is about to be shot. The secret service agent mistakes our warning as a threat and proceeds to tackle us. In doing so, he takes his eyes off the book depository building and misses Lee Havery Oswald taking aim as the motorcade enters Dealy plaza. Had we never time traveled to Dallas, November 22, 1963, the agent would have had eyes on Oswald and may have saved Kennedy... but since you time traveled, history is preserved.))
In my own work, I use the mantra "The past is Stone, the future is clay, the present is a kiln" to work around the implication of lack of free will that the Bootstrap paradox creates. Essentially how this works is that people who do not know anything about the future events may change the course of history, but any knowledge of future events prior to them happening will cause them to become certain as soon as the event is known. this means that it is possible for time travelers to change history, so long as they don't directly affect the change... essentially they have to play a very subtle manipulation game to get people in the past to make the choice for themselves that will alter the past (In our Kennedy scenario, we shouldn't warn the secret service agent about the president's imminent assasination, but if we stand with our back to the book depository and talk to him about the wonderful weather, he might have enough of our distracting yammering to turn his head and look at us with intent to tell us to buzz off... at the exact moment Oswald is taking aim... allowing him to give a "get down" alert that allows Kennedy to react just in time to save his life).
[Answer]
You are on Timeline 1 and travel back (or forwards that doesnt matter!). This lands you on parallel timeline 2, where everything is the same except that you are there now and can kill your own grandfather without repercussions.
A nice extra "rule" is that you cant go back to timeline 1. If you time travel again you end up in timeline 3. This is important, since any time travel from timeline 1 to timeline 2 will instantly have happened. If you are the first time traveler in 2020 and go to the year 2000 and the second time traveler only does so in 2030 but goes back to 1 minute to before you arrive, then time traveler 2 will already be there and changing the timeline you end up in as you dont end up in seperate timelines.
] |
[Question]
[
They don't posses any advanced knowledge, their knowledge is in fact irrelevant, just their possible actions (it doesn't matter how irrational those actions might be) that would cause significant environmental changes.
* Any kind of climate change. Making Earth less hospitable, making a very earth-like world more like Earth - it doesn't matter.
* A long period of time is allowed (let's say a maximum timeframe is 100 000 years). Natural climate change doesn't count. Reaching industrialization doesn't count, so let's assume we halt their civilization's development at an earlier point if it takes them too long.
* Whole mankind globally is involved.
* If it would still not be possible, what changes to the world would allow it?
**How could mankind of ancient times cause significant climate change?**
[Answer]
# Large scale albedo changes
Albedo is the reflectivity of solar radiation off the surface of a planet or moon or something. It represents how much of the solar radiation is sent back into space as opposed to how much is retained.
The planetary albedo of the Earth is about 0.367. However, this varies greatly from place to place. Cumulus clouds and fresh snow can have an albedo of 0.7 or more; that is, 70% of incident radiation is reflected right back into space. On the other hand the ocean's albedo is about 0.08, which means that 92% of the solar radiation striking the ocean stays with it.
There are certain things that humans can do the change the albedo. Most plausibly for ancient man, a forest might have an albedo of 0.1 while dry bare soil might be 0.3. Thus, if Man could change the environment from one to the other over a large enough area, he could change the Earth's albedo.
# How much area is reasonable for Man to change?
There were some large scale deforestation incidents in the ancient world. Possibly the biggest was the reduction of the Gangetic Plains. 10,000 years ago the area from [Delhi](https://en.wikipedia.org/wiki/Upper_Gangetic_Plains_moist_deciduous_forests) to [Bengal](https://en.wikipedia.org/wiki/Lower_Gangetic_plains_moist_deciduous_forests) was covered in moist deciduous tropical forest; an area of around 500,000 km$^2$. This was ultimately replaced by cropland over the period from roughly 1000 BC to 1000 AD. Crops and irrigated soil have an albedo not too much higher than a forest, so the climate change impact wasn't much. But that Ganges plain is actually pretty dry; had humans not spent so much time irrigating it could have ended up a barren semi-desert like the African Sahel.
This 500,000 km$^2$ represents 0.1% of the Earth's surface. If .1% of the Earth's surface increased in albedo by 20 percentage points, the overall Earth's albedo would have changed from 0.367 to about 0.3677; not much.
But what is super self destructive humans did this to similar decidous tropical forests around the world? There are 2.7 million km$^2$ of [miombo](https://en.wikipedia.org/wiki/Miombo) woodland in southern Africa; about 0.7 million km$^2$ more in India's northern Deccan Plateau; 0.4 million in Indochina; 0.3 million on the Pacific coast of Central America; and 0.9 million in the Dry Chaco of Argentina and Bolivia. This is about 5.5 million km$^2$ of forest total, or up to 1.1% of the Earth's surface. The albedo effect of turning all this forest into barrens would be from 0.367 to 0.375.
# What does that albedo change do?
Albedo can be used along with stellar luminosity and orbital distance to calculate planetary [effective temperature](https://en.wikipedia.org/wiki/Effective_temperature) using
$$T\_{eff} = \sqrt[4]{\frac{1}{4}\frac{L(1-a)}{4\pi\epsilon\sigma R^2}}$$ where $\sigma$ is the [Stefan-Boltzman constant](https://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_constant) ($3.67\times10^{-8} \text{W m}^{-2}\text{K}^{-4}$); $\epsilon$ is planetary emissivity (0.96 for Earth); $R$ is distance from the sun ($1.50\times10^{11} \text{ m}$); $L$ is the luminosity of the sun ($3.83\times10^{26} \text{ W}$); and $a$ is albedo.
For Earth's albedo of 0.367, $T\_{eff} = 276.5 \text{ K}$. This is a bit low; planetary average temp is more like 285 K, and the difference is mostly due to the greenhouse effect. But it is close enough to demonstrate the changes. When albedo raises to 0.375, $T\_{eff} = 275.6 \text{ K}$. This is about 1 degree of cooling from albedo changes, or about the same magnitude as the heating that we have currently caused due to climate change.
# Conclusion
The ancients had it in their power to change the climate the same amount that we have changed it today. However, this will require them to cut down some 5 million km$^2$ of forest; an area about twice the size of Argentina. And not just cut it down, leave it fallow so its turns into a scrubby desert with lots of exposed dirt.
Now, humanity certainly has the capacity to do this, even with stone age technology. All these forests I listed have dry seasons of more than 6 months. It wouldn't be too much work to set everything on fire at the end of the dry season. As a double bonus, all these forests have heavy monsoonal rains during the wet season, so if you timed it just right, you could get the monsoon to wash all the ashes away, leaving parched, unfertile soil that would take centuries to recover.
This seems a bit extreme, but given the sorts of things we have and are doing to the Earth, maybe we should consider ourselves lucky this didn't happen already.
[Answer]
Both [Iceland](https://www.npr.org/templates/story/story.php?storyId=16835101) and [Easter Island](http://scribol.com/anthropology-and-history/archaelogy/how-deforestation-caused-easter-islands-society-to-collapse/) were deforested by people who settled there. The Vikings let their farm animals loose and they probably used a fair bit of wood for keeping warm, boats, huts and metallurgy. The combination left the Island deforested. What happened on Easter Island is less clear but similar result.
Whether such an outcome is likely over an entire continent is unclear, because a society generally speaking, develops within a certain amount of sustainability and the deforestation happens when they go somewhere new that can't sustain their way of life. (different predators for example, so farm animals can grow unchecked). Traveling with invasive species can do a lot of harm, even if it's unintended.
Mentioned in the other thread, Large scale agriculture, burning to clear-cut forests could also be a factor. Enough farming and deforestation can drive climate change, though probably not as fast as we're doing it now, but it's possible. It's theorized, that [human agriculture had a warming effect](https://www.sciencedaily.com/releases/2010/06/100630162353.htm) on the planet that continues to this day. Both the deforestation and Methane (aka cow-farts) likely have warming effects.
That said, all those effects are likely smaller than our current warming and not huge drivers, so significant change is somewhat unlikely, but if combined with naturally occurring variation due to orbital variation in the same direction, it's reasonably possible.
[Answer]
They could do it the same way we are doing it today, by burning large quantities of stored fossil fuel, releasing large amounts of Carbon Dioxide into the atmosphere.
Based on the low population numbers burning them for semi useful purposes are out. Also due to the low technology they are going to be limited to near surface deposits.
The most likely candidates that I can see are large out of control burning events. A few come to mind, there are a disturbing number of [underground coal seam fires](https://en.wikipedia.org/wiki/Coal_seam_fire), where the deposits of coal are lit on fire and keep on burning through the underground seam over years burning huge amounts of coal. Many of these coal seams start near the surface so early low tech mining or surface harvesting, could lead to burning huge amounts of deep underground coal.
This type of underground burning can happen for natural gas and oil sources as well. A semi famous example is the Darvaza gas crater in Turkmenistan, which is known locally as the "Door to Hell", where a Soviet drill site collapsed in 1971 igniting the near surface natural gas, it has been burning ever since.
[](https://i.stack.imgur.com/0itE0.jpg)
The interesting thing is that these large scale burning events, could actually lower temperatures in the short term by releasing huge amounts of soot into the atmosphere, similar to a large volcanic eruption, as well as causing acid rain and other environmental problems.
More near surface deposits or earlier, widespread, not very safe, use of fossil fuels would make these events more likely and have a bigger effect on global climate.
[Answer]
Okay, so our ancient people really have it out for future generations. I'd start with Viking technology - they're going to want to be able to sail long distances, although this isn't strictly necessary. Other answers have mentioned deforestation, but that alone won't actually have that huge of an impact. They can certainly put some effort into that, but what's really going give you the most bang for your medieval buck is:
# Burning Peat Bogs and Coal Seams
It turns out that burning coal seams represent 3% of the world's global carbon emissions. If we actively search for and ignite these coal seams, we can increase this number. Peat bogs have similar effects. I recommend that we concentrate our search in the Arctic. Greenland especially. [Recent fires in Greenland](http://www.bbc.com/news/science-environment-40877099) have been a cause for concern among many scientists. These fires do of course cause major release of carbon from the burning peat and coal, but they also release black soot, which lowers the albedo of the surrounding ice, which can cause widespread melting. Once the ice is gone, it's possible that the permafrost would start melting as well, releasing large amounts of methane, a very potent greenhouse gas. If you really really want to get the most out of this, I would recommend that your ancient climate scientists find a way to distribute this soot over as large an area as possible.
[Answer]
The most obvious is large scale deforestation.
Changes rain patterns, erosion, heat absorption, soil properties, changes the makeup of the atmosphere, etc. And it actually happened, too.
Almost the opposite is large scale irrigation, which also happened in ancient times
[Answer]
Realistically, man in ancient times was too few in numbers to make a meaningful impact even with today's technology unless they knew exactly what they were doing and it was deliberate.
That said, the easiest way to have an impact on climate change is to add carbon to the atmosphere in great numbers. About the only way that ancient man could do that is to burn trees, forests, whatever coal they could get their hands on.
Let's assume that they set fire to every forest they could find. If man was sufficiently spread out and had access to every forest on Earth, it's possible this could be done. It would have devastating effects on the ecology and it would be bad for them in terms of their own survival, not to mention that the wood going up in smoke would have been extremely useful. But, if they did that in a concerted and sustained effort, burning back even the regrowth, it's *possible* that you could put enough carbon in the atmosphere through fires to have an effect.
My concern about the above is that I don't know if this would represent *significant* climate change. I'd need to know more about the forest assets on the Earth at the given time, what access to coal they had (ancient man certainly had some coal at his disposal) in order to put numbers down, but the fact that the forests would have a role to play in any recovery (stripping out the carbon via photosynthesis) would tend to indicate that you'd be adding carbon AND reducing the ability to remove it from the atmosphere at the same time.
Also, with their numbers and limited communication strategies, this kind of concerted global effort seems highly unlikely. That said, if that issue was addressed, it's possible for ancient man to have an impact on climate; it's just not clear if that impact would be significant.
[Answer]
The easiest way to change the environment in a large way is to introduce (or eradicate) a species that drastically changes the ecosystem.
[Invasive species](https://en.wikipedia.org/wiki/Invasive_species) can end up growing out of control because the ecosystem they were introduced to has not evolved defense mechanisms. They may then decimate existing species through predation or competition.
In the real world there are many examples of humans transporting a species from one place to another where the grow out of control. I don't think this has led to huge climate change, but it is easy to imagine a situation where this could happen. e.g. introducing wood-eating beetles might destroy forests, or eradicating apex predators may cause an explosion of herbivores that consume all the plants.
[Answer]
No need to think about what-would, it's enough to focus on things we've already done:
There is theory that we've started changing the climate ~10000 years ago, when we've invented agriculture. What was the result of it? That we've stopped the ice age. You can start researching it from Wikipedia article on ["early anthropocene"](https://en.wikipedia.org/wiki/Early_anthropocene)
Another, more recent, more drastic, however more mechanized event was the [dust bowl](https://en.wikipedia.org/wiki/Dust_Bowl) of 1930. On the one hand it's commonly thought as made possible by mechanization of farming. On the other, it was done with nothing else but plowing, so it's imaginable that given enough effort it could be replicated with nothing else but a horse-drawn plough (I can't find atm any references if deep plowing is possible with a horse or if the results are good enough to outweigh working the horse so hard)
[Answer]
# Kill lots of people
According to Julia Pongratz, Genghis Khan and his Mongol hordes killed so many people that it led to 700 million tons of carbon absorbed from the atmosphere.
>
> ... But in the case of the Mongol invasions, which had the biggest impact of the four events studied, re-growth on depopulated lands stockpiled nearly 700 million tons of carbon absorbed from the atmosphere. This is equivalent to the world’s total annual demand for gasoline today. ...
>
>
>
<https://carnegiescience.edu/news/war-plague-no-match-deforestation-driving-co2-buildup>
[Answer]
One simple way has happened many times in the past and even into modern times.
Slash and burn agriculture is one of the oldest methods, basically they chop a new bit of forest down and set fire to it. The ash fertilizes the land and they plant their gardens. As recently as the 80's or 90's one of these fires got out of control in Indonesia due to poor management and peaty soil and the smoke changed the weather locally for quite a while as well as wiping out huge tracts of forest. Scale this up and you can have permanent climate change.
[Answer]
There's some real-life examples. As one example for all, there is a hypothesis (Lewis, Maslin) that a significant cooling occurred all over the world (and particularly in Europe, where it led to crop failures, epidemics, all the usual stuff) when Native Americans started to die out during/following the Columbian exchange.
Despite the still common picture of the natives as being "in harmony with nature" and such, they engaged in massive deforestation practices, just like the Europeans. And when they died out, the forests returned with a vengeance. This, according to the hypothesis, caused a substantial temporary drop in the levels of carbon dioxide. A natural forest is carbon neutral on average - they capture carbon dioxide from air, but also release it when the trees die and decay. But this is not true of an "invasion" like this - you have lots of new, healthy and young trees, and very little decay. As the forests matured and began to again be destroyed by the new colonists, levels started raising again. We can't tell how long the recovery would last naturally, since it was interrupted about two centuries later with the arrival of the industrial revolution.
In short:
* It happened as a result of a civilisation *collapse*
* The effects appeared throughout a period of just a couple of years
* The effects lasted for centuries at least
* It had a significant impact on agricultural output, but not nearly enough to destroy Europe, much less humans all over the world - though it should be noted that there were also significant benefits coming from the colonisation that may have reduced the severity somewhat
If true, it also shows one way you can significantly alter climate through one big change where a series of small changes over large enough timescales would have little or no effect (there was no "symmetrical" heating when the natives originally cut those trees - probably because the expansion of agriculture progressed over hundreds of years). This could perhaps be exacerbated by some weird rituals that would make such grand changes to the environment periodically - like burning down massive areas of forest, and then ten years later fostering a replanting of the forest, rinse and repeat.
[Answer]
As Luaan mentioned, "natives living in harmony with nature" is a myth. Native South American tribes used to set up camp, hunt until nothing much larger than a hand was left, then move.
So, the general idea is that Australia was a large forest until the aborigines' ancestors arrived, say 40K years ago, and turned it all into grassland (which subsequently turned to desert; expect the same in the Amazon now). E.g., [this article](https://theconversation.com/how-aboriginal-burning-changed-australias-climate-4454) argues it has timed monsoons and similar large-scale events.
Basically, you don't need tech you just need anything large-scale. For example the monsoons: Mis-time them sufficiently, and things become unlivable --- 11months drought followed by a month of floods destroying whatever is left; with water running off an impenetrable ground so you next month your reserve runs dry.
[Answer]
# Goats.
Having goats enough, and time (it already happened more than once [in ancient times](http://journals.sagepub.com/doi/abs/10.1177/0959683616670470), and [is still happening today](https://ir.library.oregonstate.edu/concern/defaults/zs25x899d)), a grassland near enough to the equilibrium can be turned into a desert. The process is self-sustaining (goats migrate to graze on still fertile land, [extending the desert](http://waset.org/publications/8082/importance-of-pastoral-human-factor-overloading-in-land-desertification-case-studies-in-northeastern-libya)).
[Answer]
Perhaps excessive population, leading to overconsumption of natural resources, and the eradication of natural habitats, would be the simplest (though most boring) reasoning as to how ancient humans could disturb the climate. Every human consumes a piece of nature, and the more technology there is, the more aggressive the consumption is, in terms of both natural resources and energy demand.
There are some similarities to the behavioral sink study:
<https://en.wikipedia.org/wiki/Behavioral_sink>
Further more, as resources are consumed, there's a direct influence in climate via CO2 emissions, and so forth, particularly when you observe deforestation:
<https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1871823/>
So, even if it isn't an immediate collapse, the climate of the whole world could possibly be severely altered just through resource consumption, begotten by a massive population bloom.
As for the reverse...
A drastic depopulation event could reduce the energy toll. It wouldn't necessarily change the climate, so much as help halt the change of it.
Triggering volcanic activity can reduce the temperature of the planet by sheltering it from sunlight. Granted, that approach could have severely damaging consequences.
<http://www.newsweek.com/artificially-cool-earth-volcano-eruptions-extremely-dangerous-711203>
Additionally, reforestation could conceivably effect climate by reducing CO2 in the atmosphere, managing watershed, and creating evaporative patterns that can influence rainfall.
<https://www.theguardian.com/environment/2012/nov/29/planting-trees-climate-change>
[Answer]
Could humanity be set up by a natural phenomenon? Let's say there is a period of good weather that leads to a worldwide population increase. Then an eruption or comet causes a global but short term cold period. People all over the world fell trees to build defenses. They build ships to find new place to live or to hunt more distant sea animals. Some might burn brush to make hunting easier. Burn trees to make charcoal for forging weapons. If your earth-like planet starts out with less forests and more people the effect could be devastating for the environment.
This happened on small scale in the 1250s. [Irish chronicles say 1253 was](https://celt.ucc.ie//published/T100010A/index.html) a great year for food production. [An eruption in Indonesia in 1257](http://www.dailymail.co.uk/sciencetech/article-2440039/The-13th-Century-volcanic-explosion-triggered-Little-Ice-Age-created-Far-Eastern-Pompeii-just-waiting-discovered.html) caused a two year famine (and left deposits in both the Arctic and Antarctic). The Mississippian culture in the midwest US began its decline. This leads into the little ice age here on Earth.
Other answers describe what humans could do to change climate. My answer is about getting them all to do it at the same time.
[Answer]
Redirecting rivers may be some help by causing desertification and changes in local rainfall. Directing them into blind valleys may cause salt pans that reflect sunlight locally which may not be desired.
The best way to melt ice is to cover it with something that will absorb more sunlight. A black cloth over the edges of the north and south icecaps that is moved in as it melts would eventually raise sea levels and change salinity enough to interrupt the normal temperate currents from the traditionally habitable zones. They zones may move or almost disappear. Alternately slag and ash may be used but this will be covered with snow so something that will be shaken clean and lifted above new snow by thousands of conscript workers. As soon as the ice layer is melted and the ground surface is reached it could be covered with black pitch, slag or stones to increase the local air temperature and the black cloth repositioned over the retreating ice sheet. This could be tested first on all inland glaciers as the system is deployed.
Deforestation may also work due to albedo changes. It may also affect the greenhouse CO2 levels, however it may eventually be cancelled by some virulent ocean plankton that starts to grow in the increased CO2 reducing atmospheric CO2 levels. Alternately if all plants are killed then animals will have no oxygen to breath. A plague that eats all plant life should be enough to test the theory :-/
] |
[Question]
[
A great way to introduce [advanced technology](http://tvtropes.org/pmwiki/pmwiki.php/Main/ClarkesThirdLaw) to a story is to have it be of [extraterrestrial origin](http://tvtropes.org/pmwiki/pmwiki.php/Main/ImportedAlienPhlebotinum). E.g. have a spaceship crash on earth, or, like I was planning to, put a derelict spaceport on [the ~~dark~~far side of the moon](https://en.wikipedia.org/wiki/The_Dark_Side_of_the_Moon) and have humanity discover it *by accident*.
What I mean with *by accident* is having humanity progress far enough to set up things such as *a moon base* (complete with its own space elevator), a *research habitat orbiting mars* and regular traffic between these & earth.
Then have someone discover, *accidentally*, an object on the far side of the moon that is just *too regular* to be natural (be that from space, or from an expedition on the far side itself).
Now the thing is that I do not want that discovery to happen too early. E.g. by [rockets circling the moon](https://en.wikipedia.org/wiki/List_of_Apollo_missions#Manned_Apollo_missions) or similar.
---
**Q: How much *surface-area* can I give my derelict alien spaceport to prevent it from discovery through routine measures?**
[Answer]
The latest [publicly available moon map](https://www.nasa.gov/multimedia/imagegallery/image_feature_2110.html) has a resolution of roughly 328 feet. Any object smaller than that would be a single pixel, and would be difficult to pick out from the background jumble. You could probably get away with covering four full pixels (so 656 feet or nearly 200 m) before people started looking askance at your structure.
Note that smaller objects could well still be identified by more detailed surveys of specific sites; the 328 feet is the standard at which we have mapped the *entire* moon. Individual smaller locations have been examined at higher resolutions, but they're normally associated with human activity or other interesting phenomena. If your alien construct is keeping nice and quiet and not drawing attention to itself, it could well be just glossed over.
[Answer]
# Cover it in regolith
The moon hasn't seen a lot of activity in the last few billion years, leading to it being mostly covered in a loose layer of [fine dust](https://en.wikipedia.org/wiki/Lunar_soil), called regolith. [This layer](https://en.wikipedia.org/wiki/Regolith#Moon) is 4-5 meters thick in the smooth mares, and up to 15m thick in the highlands.
Also, given that the moon's atmosphere offers no protection against cosmic rays, it would be easy to justify an alien base being built mostly or entirely below ground.
If this is the case, a base in the highlands covered in 15m of dust and not near anything else of special interest could be quite difficult to detect from orbit and could go undiscovered for a long time. The base could have quite a large surface area (I hesitate to say unlimited) and still be reasonably hard to find by accident.
[Answer]
Watch your density, too.
Gravity mapping is a thing, and we've already done a pretty indepth gravity map of the Moon (the GRAIL program). It can show unusually dense areas, so if your object has a considerable amount of metals and is big enough, even if it's hidden or cloaked, gravity mapping could make it show up like a big red flag. At the least, a mining company might make it a priority to dig up once they get a presence on the Moon.
[Answer]
Current moon maps may have relatively low resolutions, but as image capturing ability increases, those resolutions could reveal sharper and sharper images. Depending on how advanced your civilization is, you could give the space ports access points that are only a couple square meters, or plenty of space but no visible space at all.
**Mostly Underground**
Your civilization might have preferred their constructs to be beneath the surface, allowing for a better defensive posture and grater safety from flying space debris. In this case, the space port in question could have several above-ground elevators that could be accidentally stumbled upon by on-foot explorers, but would be completely missed by even the sharpest orbiting cameras. The port docks can then be hidden beneath craters as very large circular doors that -due to various small impacts or large-scale lunar disturbance - are now covered by dust and rocks.
**Cloaking**
If your civilization is advanced enough for active cloaking technologies, they might also have ports hidden under such cloaking. In this case, your explorer(s) can simply be walking and suddenly see something no orbiting camera has ever been able to see. Alternatively, the cloaking systems finally decay enough that they shut down, allowing someone in the vicinity to see the port for the first time.
[Answer]
I don't have a direct answer to the "how big" question, but some considerations:
One way you could make your object much less likely to be discovered by routine surveying is to put it near one of the Moon's poles.
Natural (cheap) ways to get to and orbit the Moon involve orbits closeish to the plane of the ecliptic; Earth's equator is around 23 degrees off from the ecliptic, and the Moon's inclination is only about 5 degrees. If you're talking about establishing a Moon base with a space elevator, the space elevator also is most naturally on or near the Moon's equator. Any views of the poles from these "natural" orbits will be at an oblique angle, making it especially hard to see over high terrain or into holes.
So sites near the poles of the Moon are likely to receive much less scrutiny than sites near its equator, even when there is regular traffic to/from permanent bases on the moon. Undoubtedly there will be *some* surveys of the area your object is in (we've already mapped the entire surface of the moon). But at any given "size", areas near the poles will likely be the last regions where an object of that size could escape detection.
[Answer]
Even a small planet is a big place, so it doesn't necessarily need to be hidden. It can be observed and even documented. It just needs to be dismissed. IMO this makes it **so** much more interesting. It just needs to be plausible. Because if we were ever to discover evidence of an alien presence on the moon (or discover Atlantis, for that matter), reality would seem totally implausible, compared to anything you might conceive.
For example:
>
> An oversight in Lunar mapping, combined with the age of the facility.
>
>
>
A large (but indeterminate) number of years ago, an unknown agency which may have been of either terrestrial or extraterrestrial origin visited the moon and built a large base below-ground, but with a significant number of above-ground structures spread over approximately 20 sq. km. Over the years, these structures were damaged by micrometeorites and partially-covered by regolith, but they remained largely visible both from the surface and from orbit, once selenologists knew what to look for.
Early Lunar mapping efforts spotted these structures. However, they were looking for natural formations, not artificial structures. Because of the fact that the outlines were softened by damage and cover, there was nothing to indicate by computer analysis that they weren't natural, and human analysts determined that they were an unusually-regular rock formation. No further investigation was done, and further scrutiny wasn't given to them in later mapping efforts because they had already been identified.
Jump forward in time...a group of Lunar geologists decides to investigate these rock formations first-hand, to determine why they're so regular. When they arrive, it's immediately obvious that they're artificial, causing the leader of the expedition to exclaim:
>
> Holy mackerel! How the heck can we have missed something this **big** on a planet this **small** for the past five hundred years?
>
>
>
...or something with a similar meaning, but not family-friendly.
Once observed, a review of old data showed that it should have been **obvious** that they were of an artificial nature.
] |
[Question]
[
Your large spaceship is damaged beyond repair. You manage to get it close enough to a planet so that you can release emergency shuttle craft. You have very little control over the ship and won't be able control it much longer.
The story demands that the ruined ship still be in orbit or close by (but not on planet) for millenia. Where do you leave the ship so that it doesn't:
* rain down on you while re-entering the atmosphere in the shuttle craft
* crash land onto the planet over the following years (I don't mind a few pieces making arkfa...landfall but the ship should preferably stay in space)
* slingshot itself into outer space
* coast on, into the sun ala BSG style.
The planet is:
* slightly smaller than Earth
* has a planetary rings
* two small shephard moons chasing each other through the rings
* a small moon within its Roche limit
* either one or two larger moons
**Where is the best place to park it for the foreseeable longterm before a towtruck can be arranged and how long could it realistically stay in this sort of position without constant maneuvers before orbital mechanics pick it up and take it to the impound yard?** Note: I don't actually intend to tow it anywhere at anytime.
Is crashing it into one of the larger moons the only option or is there a way to possibly keep this ruined hulking artifact hanging forlornly in space.
[Answer]
The orbits of larger moons should be stable and mostly clear of hazards. I'd recommend placing your ship at one of their [Trojan points](https://en.wikipedia.org/wiki/Trojan_(astronomy)). Just pick the one most convenient. Closer to planet, not already occupied by something, already occupied something that is useful...
The actual mechanics can get more complex, but I see nothing in your question suggesting you need to bother with more complex solutions.
[Answer]
A simple extremely high orbit, such as the aptly named [Graveyard Orbit](https://en.wikipedia.org/wiki/Graveyard_orbit) - These orbits are really high and designed so that the satellites will be there for a very, very long time. An orbit should be able to be accomplished outside the ring system (And thus, outside major influence from the moons).
For a more permanent solution, depending on how small the moons are, you could land on one of them. HOWEVER, a spacecraft not designed to land will almost certainly be destroyed in the process.
[Answer]
The answer depends on what close means.
If your spacecraft can make a "modest effort at station keeping" park it in a [halo](https://en.wikipedia.org/wiki/Halo_orbit) orbit near the first or second [Lagrange point](https://en.wikipedia.org/wiki/Lagrangian_point) between the planet and the sun. The Earth-Sun-L1 point is 0.01 AU from Earth. If your spacecraft cannot make any effort at station keeping, those orbits will eventually decay.
If one of the moons is far more massive than the rest, you could orbit that moon, or station-keep in the planet-moon-lagrange points.
You could simply orbit the planet very closely or farther away than its other bodies. If you are too far out, you would be orbiting the sun instead of the planet.
You could orbit the sun at a 90 degree angle to the elliptic and slightly closer or farther away than the planet. The pilot would come close to the planet, set the orbit, and then eject. The ship would have an orbital period slightly longer than the orbit of the planet. It would cross the elliptic twice a year. Each of these crosses would have a small chance of changing its orbit due to interaction with the planet.
You could orbit the sun at a 90 degree angle at the same distance as the planet. This would give you the same orbital period as the planet. You would have to make sure that your orbit crosses the elliptic when the planet is not around. If the pilot ejects at the right time, sufficiently far from the planet, the life boat can use the ship's momentum and make a smallish course correction to get to the planet. This solution involves chilling out in a life boat for a month or two.
You could get lucky. Space is big. The odds of actually crashing into anything in a given year are astronomically small. Eventually it will happen, but eventually might be a million years from now. If everything that could crash into something did, we wouldn't have any near Earth asteroids.
[Answer]
If this is a story, putting the ship in orbit around the sun offers storytelling options. It would not be readily available anytime but you state you do not need it for millennia. Do you want to just look at it and think about it?
If not, a cool thing would be to put the ship in a huge comet-like orbit to keep it out of trouble with moons, rings etc. If you want to reclaim it, you would need to be ready for when it comes back. In this scenario you would have to time your intervention to retrieve it for when the ship's orbit brings it close to the planet.
[Answer]
I'll assume that at least one of the moons has no residual atmosphere or orbital debris. **Park your spaceship in orbit around that moon, say halfway down into that moon's gravity well, for stability.**
[Answer]
The best possible way is to put the spaceship on stable orbit around the planet, an orbit that would not get it close to any of the moons. Crash-landing on any of the moons or the planet itself is not a good option, because such a crash would be so violent it's very unlikely that salvaging the ship afterwards would be possible.
However, if that is only your space engines that are malfunctioning, but landing systems are somehow in good order, you can try to land it safely on the planet.
P.S. I would advise against "parking" spaceship in Lagrangian points. Trojans are generally less stable than normal planets and moons.
[Answer]
Sure, park it in an orbit around the planet.
The planet is good enough to keep all that stuff flying around for probably millions of years, it will be good enough to home your millennium falcon.
5000 km above upper layers of atmosphere and it will stay there for a long long time.
[Answer]
The Lagrange Points have been mentioned. L4 and L5 (leading and trailing the large moon) are in stable equilibrium. If something big enough comes along, the ship would be pulled from its position but there is a "pull" toward the center of that point that would correct any small tugs against the spacecraft.
Another method is to land/crash it on the moon. It won't be going anywhere then.
[Answer]
Since they have the ability to select where to put the ship it clearly has some propulsion. A landing on one of the shepherd moons strikes me as possibility. They are small, it won't take much thrust to actually land there and even if it's a crash it won't do much damage.
A quick analysis will show they've been around for quite some time shaping the rings, thus landing on them is unlikely to result in unexpected forces tossing the ship away.
[Answer]
The real difficulty in this type of situation is determining orbital stability quickly.
On Earth we have made observations for a long time and found most of the relevant orbiting bodies and measured their orbital parameters very precisely, and given some supercomputer time could simulate an orbit for thousands of years to determine likely stability.
If it is a star system that is not well charted or observed for any length of time you are going to have difficulty finding smaller orbiting bodies or any items on comet like long elliptical orbits. At best I would expect you could find major planets and moons maybe smaller items around the planet being orbited, but all of the orbital parameters will be very rough numbers extrapolated from the short time the ship has been in the system making observations. This is going to be especially problematic if your ship has suffered damage to sensors or computer systems or is moving through the system very quickly.
You could find a generally clear zone and set up what you thought was a long term stable orbit, but with the likely large amount of error in the measurements of the system, the probability of some long orbit comet, or asteroid/meteor shower, or simply the errors in orbital parameters adding up to major problems, goes up the longer you leave your ship in place unassisted.
In this situation, I would say landing on a sizable planet or moon would be your best bet for long term stability, so land on the large moon outside the ring system. Based on size of the moon you could bet that it has been there for a while and the larger the body the less likely it is to be perturbed by the error in your measurements of the systems orbits.
[Answer]
Unfortunately, when the ship was parked, a splash down for a large craft with little or low gravity capability was the only answer. Time is now the enemy. Biometric memory ingrams though cloning only provides the key to open the lock. Not to find what you lost. By now there are lots of keys with different agendas for the outcome of this technology, but the race is on and yet no-one even knows it's there??
] |
[Question]
[
And I'm not talking about the wimpy 32 MJ kind we have in the real world, I'm talking about the superweapon kind. Anyone familiar with Knights of Sidonia and their flagship's Heavy Mass Cannons will know what I'm talking about (<https://youtube.com/watch?v=D1GdoUDBsaE>)
This is less of a "how it's done" question and more of a "am I understanding this right" question, because my rudimentary understanding of physics tells me that if your spaceship is firing a railgun projectile with megatons or gigatons of kinetic energy behind it, recoil from the weapon should also be destroying you as well as your target. Whatever asteroid you cobbled your ship together out of probably isn't going to survive that kind of abuse unless it's made from adamantium.
Or am I wrong? I get the sneaking suspicion there's some fundamental part of how a railgun works that I'm either ignorant of or don't properly understand. Can anyone help clarify this for me?
[Answer]
The conserved quantity causing the recoil is the product of mass and velocity. The projectile is a small fraction of the mass of the ship. The recoil will be the *same* fraction of the velocity.
E.g. if the projectile is 100g and shot at a million miles per hour, and the ship was 100 tons then its recoil would be 1 mile per hour.
The additional *energy* needed to correct the motion of the ship can be in principle much smaller than what you expended on the projectile, since that’s mass times the *square* of the velocity. (The real needs will depend on how your thrusters work: how much reaction mass you are willing to lose).
[Answer]
## Hardpoints
On military vehicles there are special locations called "hardpoints". A hardpoint is a specially reinforced location on the frame that is designed to support the weight of something heavy and/or withstand the force of something with a lot of recoil.
On null-grav vehicles, a hardpoint is also a specially reinforced section of the frame, but the design of the entire frame of the vehicle also takes the location of these hardpoints into consideration, due to the lack of constant acceleration (ie: gravity), and the potential variable acceleration effects inherent in an omni-directional environment. Otherwise any recoil of weapons (or engines) being fired might damage or warp the frame, or possibly impart acceleration in an undesirable way. In reality, weapon systems would either be axially located, or would consist of multiple matched weapons (pairs, triple-config, quad-config, etc.,) placed so that they do not impart spin in any given direction.
## Acceleration
It is true that in reality, unleashing a weapon with a exa-joule or zetta-joule output would impart acceleration away from the direction of fire. Even smaller weapons would impart some fraction of acceleration which may result in deflection of angle of travel or even in spin.
Therefore, the frame of a vessel mounting such a capital weapon must be designed to not only withstand the acceleration force of the weapon itself, it must also be able to withstand the force of all the weapons it mounts, plus the engines, plus any impact (armor) it is designed to take, plus any gravitational stresses it may come under during travel near massive objects such as planets, stars, or maybe even stations.
[Answer]
## How long does it take to accelerate the projectile?
If you have a really *long* launcher, you can fling lumps of metal around at great speeds and not have ship-shattering recoil. What the ship feels instead is a continuous push from the launcher over a length of time.
Let me explain that will some simple maths.
The product of $Force\times Time$ is going to be the total amount of energy imparted into the projectile. You can push really hard for a short length of time, or you can push gently for a longer period of time, and the results will be the same.
When designing your railgun/mass-driver/doomsday-weapon, this is one of the factors you need to consider.
Why?
Newton's Third Law: for every action, there's an equal and opposite *re*action.
If you push hard against something, the something pushes back hard. If you push against it too hard, you'll damage yourself.
[Answer]
It's not specific to railguns. Railguns aren't magic. Rocket engines work exactly the same way - they throw mass at (relatively) huge velocities. So why doesn't a rocket engine break your ship apart?
First, there's the issue of momentum and inertia. Your is much more massive than the projectile, so the recoil only causes a tiny amount of change in the velocity of the ship - a small acceleration. This is extremely important in weapons like railguns (and impulse engines of any kind) - the energy of the projectile goes up with the square of the velocity, but the momentum only goes up linearly. And the conserved quantity here is momentum - so you can increase the energy of the projectile while keeping the recoil identical "simply" by making the projectile less massive. Mind you, energy isn't the only thing you care about with a projectile, but most sci-fi railguns don't care too much about the momentum of the projectile. Lasers are an extreme example - they fire "rounds" that move *at the speed of light*, but impart only an absurdly tiny amount of momentum (though not zero - you can use this to construct photonic drives or solar sails and the like).
Second, the force of the launch is much more spread out over time. You're accelerating the projectile through a barrel - and the length of the barrel is the difference between the impact of the projectile on the target and on the firing ship. If you have a barrel that's ten meters long, that gives you a lot lower acceleration than when the projectile hits a piece of armour.
Third, the force of the launch is a lot better spread over area as well. The guns are mounted in specially hardened parts of the hull, in their own weapon mounts which may have some sort of recoil compensation - for example, electromagnetic "springs", or throwing something heavy with the same momentum in the opposite direction of the launch. The biggest rail-guns in sci-fi are invariably in something called a "spinal mount" - basically a massive hardpoint going through the whole core of the ship. It's not a gun mounted on a ship anymore, really - it's more that the ship is just a few bits around the gun. Which also means that most of the mass is the gun itself, and the recoil is quite tiny in the rest of the ship (all that inertia stuff :)). There's a reason why those superweapon-kinds of railguns are so huge, and often spinal-mounted - that's how they can be so powerful in the first place. And mind you, a "superweapon railgun" might as well be a weapon that redirects asteroids to inhabited planets :D
In the end, you don't even have to think about railguns and spaceships, really. When you throw a rock at someone, you can cave their skull in easily, while your arm doesn't really get any damage. It's all about making the stress as small as possible on the attacker, while maximizing it on the defender - concentrating the round's impact in time and space.
[Answer]
The basic run down of what's happening is that there is recoil, but the difference is in time.
Let's say you shoot something at a speed of 10.(obviously the numbers and units don't matter so ignore that.) The recoil is also 10. This is the same no matter whether you're using a normal cannon or rail gun.
With a cannon the 10 recoil is all delivered at T1 (or instantly) where as with a railgun, because of how it works, the recoil is delivered at T1, T2, T3, T4, T5, etc based on the number of magnets the round which equates to 10 divided by the magnets... to Recoil / Time.
So you still get the same recoil, it's just not felt because it is divided temporally, just like how ion drives work vs chemical thrusters. You can get the same velocities. It just takes longer with one over the other which impacts how you'd use them.
also, I didn't fully read it, but this should give a more in depth answer than I could ever: <https://humanlegion.com/authors-notes/railgun-recoil-pt1/>
[Answer]
# Because the ship is so much more massive than the projectile.
In Newtonian Physics, [momentum](https://en.wikipedia.org/wiki/Momentum) is mass times velocity. [Recoil](https://en.wikipedia.org/wiki/Recoil#Momentum) is determined by the momentum of the projectile being fired and the momentum of the gun carriage (in this case, the whole ship). This is Newton's Third Law: for every action there is an equal and opposite reaction. Expressed in terms of recoil...
mpvp = −msvs
Rearrange it and you can see the ratios.
mp/ms = vs/vp
So a 1 kg projectile fired at 1000 m/s will cause a 1000 kg ship to recoil back at 1 m/s.
>
> *So if a ship with a mass of 5.5 teratons and a velocity of .1c fired a 100 kiloton projectile at .7 or .99c, the recoil felt by the ship wouldn't disturb it to any great degree?*
>
>
>
Let's do the math. We need to solve for vs (recoil velocity of the ship).
mpvp = −msvs
mpvp / ms = −vs
Plug in the numbers...
ms = 5.5 × 1015 kg (5.5 teratons)
mp = 108 kg (100 metric kilotons)
vp = 2.1 × 108 m/s (.7c)
And we get vs of −3.818 m/s. The ship will hardly move.
---
***BUT WAIT!*** That's Newtonian Physics. Momentum being mass times velocity is actually a simplification for speeds much slower than the speed of light. We're working at significant fractions of the speed of light so we need to account for the [Lorentz factor](https://en.wikipedia.org/wiki/Lorentz_factor). This changes things. Momentum increases exponentially as you approach the speed of light.
The full momentum equation is: mv / sqrt(1−v2/c2). How much of a difference does this make? Let's look at our projectile in both. Newtonian momentum says a 100 kT projectile at .7c has a momentum of 2.1e16 kg·m/s. But its relativistic momentum is 2.94e16 kg·m/s. A 50% increase.
At 0.99c the momentum is almost 10 times greater! 3e16 kg·m/s vs 2.1e17 kg·m/s.
Buuuut the ship is so massive compared to the projectile that means a change of roughly −30 m/s.
[Answer]
Yes, most such weapons as depicted in fiction won't be viable.
The firing ship has a few advantages. They get to pick where the momentum and kinetic energy is deposited, while the target ship gets hit somewhere random.
They also get to accellerate the projectile over a slightly longer period and over a wider area; the length of the ship, if it is a axis-mount weapon.
But as the KE and velocity of the projectile grows, the time it has to cross the length of the ship goes to zero, which reduces the period it has to "soak" the momentum and KE of the projectile. It still can soak it over a longer distance.
Chemical bonds are limited in strength, and our conventional "matter" based engineering is limited by the strength of chemical bonds. If you accellerate a projectile to a significant fraction of c over the length of your ship, the time it takes is going to be bounded, hence the amount of momentum/energy required to be transferred per second will be bounded below.
Given the strength of chemical bonds, the amount of solid matter the projectile must be coupled with will be bounded below.
A magnetic launcher somewhat helps here, as you can push on/pull on the projectile from far away. However, there are falloff problems with magnetic fields, and near the projectile the slope of the magnetic field is going to be strong enough that no "stationary" matter is going to be permitted.
Eventually the competing "magnetic field slope falls off with distance" and "the field has to be very steep to get the accelleration we need" and "nothing can be close to the projectile and survive while stationary" are going to render the problem unsolvable, probably long before a large-fraction-of-c gun with a barrel modern-naval-ship-length order of magnitude could exist. Let alone finding a way for the crew to survive near the magnetic fields involved.
This then reduces you to fantasy physics.
One way to solve this problem is to spread accelleration over a longer period. Do a high velocity magnetic launch, then use lasers to keep on adding impulse over extremely long distances. Or, have gun barrels that are not single solid objects, but spread over an area of space the size of a planet or solar system or larger.
[Answer]
Three reasons:
* **Recoil dampener / recoil buffer / shock absorber**: We add a moving element on the ship, possibly inside the gun, which changes the lots-of-force applied by the gun over a millisecond to lots-of-force/1000 over 1 second.
* **Armor**: We know where the lots-of-force/1000 is applied, so we design the ship to withstand it.
* **Mass**: Compared to the mass of the weapons platform, the mass of the projectile is very small, which cancels out the high velocity. Thus, while the gun can serve to accelerate the ship, it's likely an inefficient drive (unless you select [a big enough gun](https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion))).
[Answer]
## Spread the force...
When materials are subjected to forces, what happens to them is determined by their properties - their strength (sheer, tensile, compressive, etc.), their brittleness, and other factors. If the force is below the threshold they can handle, then they can transmit that force externally, onto other things; if the force is too great, it causes changes internally, and the material fails.
In other words, if you push something gently, then it can pass that on to what's behind it; push too hard, and it breaks.
## Spread across space
Weapons are mounted on hardpoints, which have two main properties:
* They're made of something strong.
* They're constructed in such a way as to spread any force applied to them across as much of your craft's structure as possible.
This reduces the amount of force that any one part of your craft takes, helping to keep it below that critical threshold. The important part, however, isn't spreading the force over more *space* - it's *time* that's key.
## Spread across time
With a weapon like a cannon or railgun, you can accelerate the projectile gradually over a long track or barrel, applying force the whole time by the expansion of gas, a magnetic field, or some other means. This means you can apply a (relatively) gentle force, which adds up over time to give the projectile a very large velocity. This reduces the force that the structure has to support at any given moment while that projectile is being accelerated.
On the other hand, when that projectile strikes a target, the material of that target will be attempting to bring the projectile to rest in a much shorter time. Force is defined as the rate of change of momentum, and the time you spent giving the projectile its momentum is much longer than the amount of time it spends punching through an armour plate - the *peak* forces are much higher, and therefore more likely to exceed the threshold at which the material fails. This explains how your ship can be made of the same stuff as theirs, but theirs breaks and yours doesn't. By keeping peak forces low, your ship can spread the force out and experience the weapon fire as a slight push applied to the whole ship, while theirs has the force concentrated and experiences it as a hole being punched somewhere.
## Spread across mass
Conservation of momentum says that the total "nudge" your ship experienced has to add up to the same amount of momentum as the shove that their armour felt, but because your ship spread it over more mass, it's less noticeable. A weapon whose recoil changes the velocity of a multi-tonne ship by a few metres per second might send chunks of debris flying out at hundreds of metres per second because the chunks have so much less mass. Of course, their craft may have similar mass to yours - or even more - but because they couldn't spread the force, that didn't help them:
* Because the projectile came in at great speed, they weren't able to spread the force over more time. This meant that they exceeded the peak forces of their materials.
* Because their materials failed, they were unable to transmit the forces further through the ship and spread them over space.
* Because they couldn't spread the forces across more space, they couldn't affect a large enough of the ship to add up to much mass.
* Because they couldn't spread the force over more mass, the pieces that were affected ended up with greater velocity, which means that those pieces will then probably hit other bits of the ship at great speed...
And so the whole thing happens again until the pieces are small and/or slow enough that the materials they're hitting can stop them. This is particularly important in space, where you're likely to be in vacuum:
* There's no air to slow the pieces down, so this knock-on process is particularly effective
* There's no air to carry a shockwave, so this process is your most effective means of spreading damage through the enemy ship.
This process of generating as many fast-moving chunks as possible so as to spread the damage is called *fragmentation*. Sometimes your projectile might be designed to shatter on impact, or even explode beforehand; other times it's just about striking in such a way that you maximise the fragments thrown off (perhaps by having a round that will tumble erratically as it passes through the target rather than punching through pointy end first).
[Answer]
While both the firing ship and the target will experience the same change in energy (roughly, as there is still a minimum amount of friction in space), the way this energy is transferred is radically different.
On the receiving end, the transferral of energy is abrupt and near-instantaneous. This means that the applied Force is very large indeed.
On the sending end; the energy is applied over a trajectory, and therefore over time. This makes the Force at any instant much lower. Although it will definitely cause a backwards acceleration for the whole vessel, the material impact is much more limited.
The two material factors to keep in mind here when it comes to measuring the destruction of either party are Strain (Bend until it breaks) and Impact (punching a hole in a sheet of paper). Both of these are mostly uncorrelated. The defending ship will benefit most from a high Impact Resistance, while the firing ship will survive through its Strain Resistance.
[Answer]
If you simultaneously fired another shot in the opposite direction the motions would cancel out and the shooter would not be perturbed.
] |
[Question]
[
While sitting alone in my room today contemplating life I came up with a simple question. How do zombies take over the world when we have armies?
Let's just take the US army alone. They fought in two world wars and came up victorious both times against **armed men with rifles, explosives, tanks, helicopters**. I know that zombies are quite different from normal human beings in that once you get bitten you become one of them and start to turn other people but I can imagine a single squad of soldiers armed with machine guns taking on at least 1000 zombies.
So what I am asking is if there is any rational explanation as to how the zombies can take over the world? For clarification purposes I am talking about a universe just like ours where people know what a zombie is and how to take it out. Also no super zombies or any of that, just plain simple walkers like those found in *The Walking Dead*.
P.S. Sorry for any grammar errors. I am not a native English speaker.
EDIT: The disease is only transmissible through bites.
[Answer]
So the zombie Genre has always been a logically flawed concept, this is just another chink the chain.
To even start to address this topic you have to make assertions like:
* It is already in every country somehow
* They're undead
* Headshots are the only means to kill them
and you have to understand the tactics of zombies:
* **Ambush from ignorance:** zombies can get a lot of people because people don't yet know there is a zombie epidemic going on. Like, if you see an injured guy on the road your first instinct is to alert the authorities and try and help the guy.
* **Ambush from empathy:** after zombies have taken over lots of people invariably will have to make the choice between killing their loved one or not, while still not knowing whats going on. Imagine being a soldier and firing on little kids while not being informed. So even more get taken over. Thoughts like:
+ what if this disease is curable?
* **The swarm:** in most zombie flicks it's rarely the lone zombie that gets the people. Instead it's usually a swarm of zombies.
Now as for how to take on the army:
If suddenly the plague appears out of nowhere, you have them succumbing left and right to the various ambushes. These people are, by the way, off duty soldiers and commanders, politicians. So soldier gets bitten, goes back to base for first aid, gets the medical personnel then swarms the barracks. All the while politicians and officers are getting turned so the chain of command becomes disorganized.
(This is why it was the Navy that came out on top in WWZ, because their active duty chain of command is safely at sea)
At this point it is statistically impossible for all military installations to have been crippled. However, they have to contend with the fact that armies are built to protect their citizenry and what do they do if they encounter an apparent survivor? [shoot the survivor, turn them away to certain death, or let them in...]
After that whittling you will have hoards of zombies swarming military installations. Most installations are protected by a chain link fence, maybe even a mine field. Then try making a head shot, on a moving target, under life or death circumstances, while not knowing whats going on, with a sketchy chain of command at best. Most soldiers aren't trained to make that kind of shot, let alone not all military rifles are designed with the necessary accuracy to make that kind of shot. That is after they expend a clip or more before they realize they need to shoot them in the head.
At this point you have very few military bases, most likely those in active war-zone. Now for example take an American base in Iraq. You may have been able to fend off the plague, but suddenly you are a foreign army in a hostile zone cut off from your nation/supply chain. Just because there's a zombie plague doesn't mean the natives suddenly love you.
Now that the majority of your military, air force, and questionable amounts of your navy have been converted. You are doubtfully left with any intact outfits.
* How good are tanks, when they require special fuel and tank shells, maybe kill 10-15 a shot? At some point you will be stuck in a tin can out of fuel, out of ammo and surrounded by zombies.
* How good is automatic fire if head shots are all that counts? Sure, a well placed 50.cal might be able to take out quite a swarm, but with city populations in the 100s of thousands, how long before they run out of ammo? (Remembering they are cut off.)
* Aircraft especially are a logistical nightmare. You need a trained pilot in that aircraft, specialist mechanics to get it working, fuel, ordinance, someone to provide targeting (and the technicians working in that background to relay the coordinates to the pilot).
See, the achilles heel of any army is its supply lines. Once those are gone things become grim.
[Answer]
In practice the army could wipe out any number of zombies like the ones in 'The Walking Dead'
You can basically enclose any killing field and entice them in with a loud speaker. In fact any industrial outfit with heavy machinery could do it just by digging trenches and putting a loudspeaker in the middle somewhere and the zombies would just walk over the edge and fall in, fill it quarter the way with petrol if you want and burn them, or even set fire to it and they'll walk in anyway.
In my forestry days I lived on many farms who had diggers that would make this easy with just one guy. So the engineering corps of an army wouldn't even blink at managing it. Use their weakness against them.
Then mop up the remainder with groups wearing bite proof body armour armed with sidearms and short swords or whatever weapon you want.
[Answer]
The real answer is "it depends". Military forces are designed to be adaptable and come up with strategies and tactics against an intelligent opponent (there is an old military saying "the enemy gets a vote, too").
Anon has set the stage with a good answer, and there will indeed be a time where it is unclear what is going on and units may be overwhelmed by zombie infections from within or without. However, at some point the incredible truth finally becomes clear, and surviving units will be able to come up with some plans for action.
At its base, a zombie plague can and should be treated like any other outbreak of disease. Quarantine of infected people and areas, strict control of movement and delivery of medication if some form of anti-zombie vaccine is possible. The military members also can take heart in the fact that a virulent plague like the zombie outbreak will burn itself out in fairly short order. With areas quarantined and movement restricted, zombies will rapidly run out of new people to infect, and biologically speaking, the infected bodies will run out of energy once everyone who can be eaten is consumed, and themselves die.
Once an area has gone "cold", specialists can carefully enter and examine the area, and scouts and snipers move in to clear any remaining zombies. The dead will likely be burned to prevent pockets of disease breaking out in the rear area. The perimeter expands and is secured, and the cycle begins anew.
In many ways this also resembles the classic anti-insurgent *tache d'huile* strategy, but can also be considered a variation of the British "blockhouse" strategy used during the Boer War (*tache d'huile* dates back to the late 1800's, and the blockhouse strategy was used in the early 1900's, so it isn't like you have to invent anything new).
The greatest difficulty for the US military is the "force to space" ratio; even if every Active, Reserve and National Guard member is unaffected and working on the problem, there are far too few service members to effectively cover the Continental United States. What will happen instead is a drawn out campaign where soldiers using low tech gear like razor wire fencing and 12 gauge shotguns enclose areas to secure them, then wait until the next district is "cold", rinse and repeat. After a few months, the vast majority of the zombies will no longer be active, and the remaining areas of the United States not already quarantined will need to be systematically covered and disinfected. Once again, this will be slow and heavy work, especially if the logistical chain has been disrupted, but still doable.
[Answer]
I think in a lot of movies Zombies do not behave like they would in a real life setting. Anything that moves needs some source of energy, because of physics. So there can not be a single zombie reaching a military base like area 51 simply because it would starve/dehydrate/rot before it could get there.
Another thing to consider is that zombies basically work like supercharged humans (think of them like aggressive people without instincts to protect themselves), which means that three bullets to the chest would also kill it at least in the long run.
All in all this means no real life zombie outbreak could reach all strategic bases of a modern army, especially in some vast countries like Russia or the US.
[Answer]
Unfortunately I cannot comment so I decided to post my comment as an answer.
I just wanted to add, that if we now quickly build some robots to hep protect us from all sorts of injuries, the probability rate of a zombie apocalypse would decresase drastically, because up till now zombies are not able to infest machines. However, this could change in future scenarios.
>
> Nice
>
>
>
And please keep in mind that we have all sorts of drones, and pattern detection algorithms that could easily detect the slurping movement of the walking dead. So fighting them would probably very easy for the military.
So it is very unlikely.
[Answer]
I play a lot of video games and have a pretty good understanding of basic tactics in unreasonable situations so I'll give you a tl:dr;
The militaries lose if they can't figure out how the zombies happen fast enough to take measure to protect the vital resources then need to kill or "cure" the zombies.
The zombies win if they can spread fast enough to get their numbers past some critical point; it's a really risky zerg rush. This critical point would need to be high enough to give the side of the zombies a serious numbers advantage - I'll guess 100 to 1 but 10 or 20 to one honestly might work depending on the people fighting -, keep everyone in a state of perpetual conflict, and allow the zombies to control enough space to force the military to destroy major chunks of infrastructure in any massive destruction tactic.
There are a lot of potential holes here, but it all comes down to how fast people can adapt to the zombies and figure out how they work. That's why the people in the walking dead come from a global culture without zombie lore. If the characters knew how zombies worked beforehand then different tactics would have been used and the world might not have collapsed at all honestly.
Keep in mind that modern society is not as well equipped to fight a plague as a world war. Ebola did far more damage than it should have. Now imagine people with Ebola violently wondering around trying to spread it. That's a bit of a problem.
[Answer]
Late to the party but for what it's worth I think "The Walking Dead" did a good job explaining it.
Basically, the initial spread is by airborne virus with long enough incubation period so that a large portion of the population is infected before symptoms appear. As the number of sick people increases, some of them die and turn into zombies, panic ensues and social order breaks down.
If it's just a modern army vs zombies, zombies don't stand a chance. Zombies don't use tools, don't coordinate strategy and are really dumb. Their cognitive functions are worse than those of an animal.
[Answer]
This greatly depends on what you "want" from zombies. Short/no incubation so people realize these are a trouble straight away + zombies that are slow and without using any tools => any reasonable modern army will easily kill them, though not fast enough to prevent total destruction of the place where the outbreak started (say a major city).
But:
If you put the same setting in middle ages, you essentially have peasant revolts, just much worse - not all peasants joined revolts and zombies are tougher, so result would be very devastating.
Or give zombies ability to use tools like a normal person without any training. Secluded areas could be fine if proper measures are taken fast enough, but zombies should be able to ravage the rest. Grab a car, get somewhere, start biting people... True, news would spread faster than disease, but in the initial confusion disease could be all over the place.
Or give zombie disease X days incubation during which the infected person looks and acts normal except for the bites - then you can have just about everyone infected before anyone even realizes something is wrong.
[Answer]
The US army would not suffer a single casualty except for accidents maybe.
I feel like you are making a couple (as in 2) of mistakes here as in I don't think you fully understand the genre if you ask such questions.
1) Zombies in popular fiction have mostly been a metaphor. Humans turning into something the author thinks is bad and a couple of human beings try to survive in this new world as in not changing into what anyone else has become. It is a similar concept (not the same, it is just a similar idea) to what Sartre (and others) described in his books, a sudden realization what the world is or has become = zombie apocalypse. A concept like "army vs zombies" does not make any sense. There is no army vs humans changing. There is only people not infected yet by whatever. An army is vulnerable because the soldiers are vulnerable to becoming the enemy on their own through their own choices = giving up or becoming absorbed into the latest trend, not so much through fighting a literal battle and being bitten like rabies. Even if it is more or less just a social experiment (the walking dead series), the idea behind zombies is rarely "super monsters that kill everyone" and more just something that happened too quickly to prevent and people need to deal with it afterwards. The dude from the walking dead literally wakes up in a world that has changed.
2) There is zombie lore in any culture I am aware of. I would advice you to look at other zombies than those made up by Romero. Some European zombies for example did their evil work without ever leaving the grave. This would of course be much more effective vs an army. I don't know every single zombie lore in detail since this is not my genre, but I'm sure you will find more fitting stuff if you do some research.
[Answer]
I always thought the zombie setting, especially the slow, weak zombie setting, is just the part of the book/movie you have to suspend disbelief for the real story to unfold, because I fail to see how any modern army could fall beyond recovery from the zombie threat alone. I would say that usually, real enemies (and drama) in zombie settings come from people.
So, trying to answer your question, if some military fails once the threat is sufficiently understood, it's mostly because of "sane" people doing *anything* to get into the military safe zones. From politicians overriding security protocols for their own (or loved ones) sake, to mobs charging against entrances of well-defended military bases with trucks or their right-wing extremist neighbour's arsenal. But even that would hardly work against well isolated or well prepared bases, thus strengthening the requirement of the outbreak to appear in all countries and zones at the same time.
So the chance for all military to fail is that zombies, which after years of starvation and rot seem equally functional, can anyways win an attrition war over a world with a limited chain of supply and unable to adapt to a low-tech setting when hard-to-procure supplies deplete. But that could take much more time that usually portrayed in movies.
[Answer]
Zombies will take over the world by abuse of EEO laws and non-discriminatory policy. The zombie community will stand together in peaceful protest, and demand, "BRAINSSSS..." We as a society are in no position to deny this marginalized minority what they need to survive. Brains will be mandated to be on the menu in McDonalds and other restaurant chains, just like vegan or gluten-free foods.
Zombies will (rightfully, I say) demand an end to they oppression and prejudice inculcated by Day of the Dead, Return of the Living Dead, and other movies of this type. They will demand an equal opportunity. They will work their way into government, political, and even military positions; herein lies the answer to your question.
Once they have thus obtained these positions of superiority, they will command the strongest military and political forces on earth. They will leverage their power to take over the world. This form of attack is pretty much unstoppable.
] |
[Question]
[
In my fantasy world there exists a nomadic people known as the Ròda. The Ròda believe in the collection of knowledge, lore, and more importantly spells. They practice their beliefs by travelling in small groups with each commonly having a large wagon. They then travel from village to village and city to city actively seeking out knowledge. This has led to the Ròda being labeled as "grave robbers" and "thieves" by the mage families due to the Ròda gathering any knowledge they can: digging through ruins, eavesdropping, etc.
However they are only allowed to write down this knowledge during a full moon. This is due to the "Moon Runes" the Ròda write their tomes in (mainly to avoid thievery. Who wants to steal a empty book?) This means that at times the Ròda will have a book's worth of information they must keep in their heads. Due to how magic works in this world they'd also have to be precise when they write them down.
What strategies could the Ròda use to improve their memory? Would any substances known to a medieval society help?
Note:
* they can't jot down notes, that's heresy and can be found defeating the purpose of writing the tomes in moon tunes.
* technology is the medevial high period. However the Alchemy would stretch into early renaissance.
* spells have to be remembered basically word for word if you want to have predictable results.
[Answer]
Sagas and epics were long history lessons memorized easily by using **rhyme, rhythm and repetition of structures**, so your sages could use the same techniques.
Avicenna (980-1037) already wrote about the capacity of **memories to be linked to smells and tastes** (turns out, he was right). Maybe your Ròda chew on something while memorizing, something rich in carbohidrates like raisins or chopped almonds with honey (so the brain sees it as a pleasant activity) and do it again when they need to recall something. This kind of foods are logical for nomadic societies (the berbers had them) and they contain omega-3 (which helps a little to memory).
[Answer]
Human spatial memory is phenomenally good. Our ability to remember facts and figures sucks, but places and where things are and anything particularly out of place and interesting we can commit to memory quickly and remember for a long time.
Check out [Ed Cook](https://rads.stackoverflow.com/amzn/click/com/B002RI9GUI)s book "Remember Remember" for some fun examples. I read the first chapter a year ago and I still remember the kings of England starting with Offa of Mercia in 757. This method has really helped me with giving speeches too!
You convert what you want to remember into something stimulating and odd that has some sort of similarity so you can link the two things together. Then place that scene in a specific place (like a room in a house). You fill up the house - or whatever place you pick - then walk through the space and encounter all the things you want to remember in order. Works well in real life, and if you sort of walk people through the process of visualization that your scholars go through to memorize and recall the stored information you can make the whole thing seem alien and exciting. They did this in the recent BBC Sherlock series with Benedict Cumberbatch and his "mind palace." Also worth checking out those episodes for your story and how you can portray the recall process. The series is generally really good and I recommend you just watch the whole thing for the entertainment value.
So there you go. Have your nomad scholars train in building mind palaces and filling them with information that they can recall when they need to, and walk the readers through the process because it's easy to follow and seems totally fantastic at the same time.
[Answer]
Pre-modern people often had sages and wise men who spent their whole lives memorizing stories. Medieval clergy occasionally would memorize their whole holy book word for word. The Roda don't need anything special, because we didn't need anything special in real life.
As for writing at night, they can use a bonfire and polished bronze (really any metal) to reflect light on to their medium. Or they could do something like braille in clay tablets and etch by touch.
[Answer]
I think they would perfect the art of building mind-palaces.
Imagine that the games they played as kids revolved around associating physical items and places of their culture with either a short hand or phonetic version of their language — like how a dreidel is supposed to teach children hebrew characters
Then when they mature and have the intellectual maturity, they are taught how to visualize and imagine their own personal mind palace or land scape. They would then use the acculturated visual iconography they were inculcated with as children to populate rooms in their mind palace or trails, oasis, etc in their mental landscape.
This method of memorization is well defined and has a very old tradition. There are many texts available on how to train yourself to use it.
[Answer]
There are already several wonderful answers, suggesting the use of:
* Humans' excellent **spatial memory** ([MPram](https://worldbuilding.stackexchange.com/a/151761/756)'s and [EDL](https://worldbuilding.stackexchange.com/a/151760/756)'s answers)
* **Rhyme, rhythm** and **repetition** ([Carlos Martin](https://worldbuilding.stackexchange.com/a/151774/756)'s answer)
* **Olfactory triggers** (also [Carlos Martin](https://worldbuilding.stackexchange.com/a/151774/756)'s answer)
* **Magical memory enhancement** ([Vilx-](https://worldbuilding.stackexchange.com/a/151841/756)'s answer)
Each of these methods can work on its own or combined with others. What they all have in common is that they are methods for *individuals*. I'd like to suggest another method which can work by itself or in addition to those above, which takes advantage of the fact that the Ròda work in *groups*.
Rather than having each member in a Ròda group memorize different, independent pieces of knowledge, they can collaborate to achieve a human equivalent of a redundant memory storage system (e.g. [RAID](https://en.wikipedia.org/wiki/RAID) or [RAIM](https://en.wikipedia.org/wiki/Redundant_array_of_independent_memory)). This way, the knowledge is distributed between members in a redundant manner, so that if someone remembers a detail incorrectly, the others can identify and correct his mistake.
There are different strategies to perform this, but a basic example (based on RAID 5) could work as follows:
1. One group member (possibly the most junior member) memorizes the **first half of the text "as is"**.
2. A second member memorizes the **second half of the text "as is"**.
3. A third member (a higher ranking "priest"/"researcher") memorizes a **combination of the two halves** - his text is constructed by treating each letter as a number, and summing letter couples from the first and second text to create new letters (see example below)
A minor advantage of this strategy is that the text each member needs to remember is much shorter (though some members will need to remember seemingly arbitrary letter sequences, which are much more difficult), but the main advantage is that as long as two out of three members remember a specific letter correctly, they can correct mistakes of a third member.
For example, for the text:
`In my fantasy world there exists a nomadic people known as the Ròda`:
1. Member 1 memorizes: `"In my fantasy world there exists a"`
2. Member 2 memorizes: `" nomadic people known as the Ròda."`
3. Member 3 memorizes: `"IBozzdodnJfHOlBoCzswHhfKetmsi!kIwa,"` (`I+[space]`=`35+0`=`I`, `n+n`=`14+14`=`26+2`=`B`, `[space]+o`=`o`, `m+m`=`13+13`=`z` etc.)
Now, let's say member 1 doesn't remember the second word (`my`). It could be reconstructed by subtracting the relevant letters member 2 remembers from those member 3 remembers. They remember `ma` (of the word `nomadic`) and (`zz`) leading to `z-m = 26-13 = 13 = m`, `z-a = 26-1 = 25 = y` thus reconstructing `my`.
If there are more than 3 members, most of them can memorize normal text and only one needs to remember the verification sequence.
[Answer]
Basically any tradition from indigenous community carries some sort of help toward memorizing something.
Stories, dancing, chant, mythology, "sacred" items and clothing, totems, rituals...
Memory palaces are indeed one way to memorize in details long lists of elements.
However, it works best if it's intertwined with multiple techniques to memorize it :
A journey through the forest and the stars,
mixed with chant, dances, emotional stories of characters (often with animal traits and defying nature )...
you got yourself an indigenous mythology system used to store information!
See [Lynne Kelly's memory experiments](http://www.lynnekelly.com.au/memory-experiments/) for more details on what techniques are used and how they work.
[Answer]
As a supplement to the other answers - if you already have spells and magic, why not have a "memory spell"? Your Ròda could have learned that by heart and then just use it whenever they see the need to remember something. For example: the spell could, when cast, grant the caster perfect memory for the next 5 minutes. Everything they hear or see or smell or feel during the next 5 minutes will be stored PERFECTLY in their memory, and stay there for one month (enough to get to the next moon cycle). The mind is also a pretty spacious storage device and can store up to 100 5-minute "recordings" (trying to store more than that will overwrite the previous recordings in chronological order). After one month the enchantment on that particular memory wears off and it becomes just a regular memory, fading with time like all the others. A variation of the spell "reinforces" a memory and lets it last another month.
For extra flavor, you could create some kind of long-term effect that develops when this spell is frequently used. This would further distinguish the Ròda from the rest of the population. The effect could also be unknown and thus misattributed to something else the Ròda do, or perhaps just accepted as a part of them. Discovering the true cause could be made a major plot point down the line.
] |
Subsets and Splits