text
stringlengths 22
2.11M
|
|---|
[Question]
[
A human-like race develops into a modern society similar to ours in technological progress, with one weird difference: in their minds, they can see and hear everything that anyone else has seen or heard, ever.
They have their own private thoughts, but experiences are shared across a mental link. People aren't aware of the contents of this information inherently - while naturally able to access it, they have to spend some time navigating and thinking about a particular experience to learn any information portrayed. Not only experiences that are happening now, but all experiences they've ever been aware of are shared. In this way, even memories of the dead are passed down, so everyone is able to remember every sight and sound experienced up to tens of thousands of years to the age when their race first developed this ability.
At first the mental link was blurry and weak, but as best as they can tell, this started happening to their primitive ancestors after a large meteor wiped out an entire continent.
Ages ago their ancestors developed primitive religions based on this ability, and some modern religions still attribute the ability to being created by the gods. And while modern scientists have demonstrated that a certain part of the brain is responsible for processing the information, they can't yet explain where all the information is stored. Regardless, no one doubts this mental ability's accuracy.
I'm curious to know in this world, does political corruption happen, and if so, how does it happen?
[Answer]
After some thought I think there might be four possible vectors for "corruption", mostly assuming the definition of corruption supported is [bribery](http://www.thefreedictionary.com/bribe) (I know there are other kinds but most of them, to the best of my knowledge, have more to do with keeping secrets):
1. Distraction
2. It's part of life
3. Similar to 2 but it's intentionally done and clearly recorded as a means of protest
4. The exact same way it does now (this one would likely include all standard forms of corruption, not just bribery)
**Details**
1. Distraction might be used in the form of wide-spread boisterous activity occurring around the time of an illegal transaction. If enough distraction is provided then no one will notice the little 30 second exchange, or be interested enough to search through the shared memory to find any details leading up to it.
2. If everyone did it, (or if it were required to work with people in positions of authority), and bribery was just a part of life, then who would care?
3. If a government is taking advantage of its people, and, regardless of the fact that the people know that it is taking advantage of them, they don't have the power to do anything about it, ([see modern day America](https://mic.com/articles/87719/princeton-concludes-what-kind-of-government-america-really-has-and-it-s-not-a-democracy#.SivaLdicM)) then people could resort to a huge horde of little pittance bribes sent to those in power as a form of protest.
4. Maybe the shared memory is really just too large and time consuming to search through. If this is the case then corruption would happen a lot like it does now...
This adds an interesting possibility of people paid by those who are corrupt to search the shared memory for people who have identified the corruption, so they can kill them before they tell anyone else what to look for... (sounds like a pretty interesting basis for a world really :D )
Good luck!
[Answer]
## You have underestimated the meaning of everything
Someone is always being born, someone is always dying, someone is probably always taking a bribe, someone is always getting laid.
There are always more interesting things going on than monitoring some minor official for corruption, there's your own life going on to start with.
However the simplest way of having corruption is for it to be acceptable to the ordinary populace. They think it's an acceptable normal way of doing business, just as they consider a certain level of petty criminality to be perfectly acceptable day to day.
[Answer]
This is a (another) question of the sort "Like us, but...".
Well they would not at all be like us. Privacy, secrets and Freedom of Thought are some rather fundamental parts of our psychology. Now you have a society where these things do not exist. This will have very strong consequences that go far beyond just corruption:
* No privacy in the bedroom
* No privacy in the bathroom
* No privacy when being intimate in any kind of way, be it emotionally, religiously... when voting... when talking to your lawyer... when talking to your doctor.
* No privacy when negotiating sensitive matters, even if doing it legitimately
In short: no secrets, ever... on all levels, from individual up to state and international secrets.
Also you have set the foundation for the world of Orwell's "1984". You have enabled thought-monitoring, and — with that — thought-crime.
This means you can never make it "Like us, but...". Privacy, secrets and Freedom of Thought are essential to who we are. You would have a **radically** different world. And before we start talking about how this affects "corruption" in such a world, you would have to figure out if "corruption" is even in anyone's interrest.
**Blackmail** on the other hand... that would probably be rife. "Well you wouldn't want me to tell anyone to recall **that** particular thing you did, now would you 'dear friend'?".
In summary: you would have to need to explore this world a lot deeper than just say "It is like us, but...", because it will not be that at all.
[Answer]
For centuries, what the West calls *corruption* has been an important part of how Chinese society works. It is called [guanxi](https://en.wikipedia.org/wiki/Guanxi#In_a_government_context). Chinese who have had no contact with the West probably don't even know what corruption means. Or, a Chinese might be able to recognize corruption, but they'd think of it as a *good* thing.
I'm a westerner and of course mean no disrespect to Chinese culture at all. I find such cultural differences interesting.
[Answer]
Corruption would happen in this world the same way corruption happens in the real world, when there might be unfriendly witnesses or other reasons for 'plausible deniability' - by implication and insinuation.
So perhaps it wouldn't do to have outright negotiations, since those will be seen, and heard, and could be found in the collective memory. But a slightly over-generous gift, or being a little more helpful as a favor, to someone who has previously done a good turn (or is in a position to do the same in the future) - will probably be really difficult to pick out of all the similar gift-giving, or genuine gratitude.
And there are limits to visual interpretation of the scene - maybe that extra significant glance means I will be grateful, or *generous* if you do a favor, maybe it just means I like your haircut, who can say - especially if both parties are willing to declare it is so. Being able to access what someone sees or hears is useful, but it is not at all the same thing as getting access to what they're thinking, planning, assuming
Someone might be asking for a favor, and 'leaving' a gift behind. Or asking for that favor at the same time some other transaction is taking place, which ends up favoring the person being asked. It might be a little suspicious, but if a verbal explanation is offered it gives plausible deniability, even if both parties are treating it like a little bribe. Hey, I have this extra treat to give around... also I'm *so* grateful you assigned me this job instead of that, or else I might not have had the extra to give away, right?
The shared memory might encourage a culture where favors and generosity are the norm, since it's easier to figure out what people might need - and generosity is an encouraged trait. But it is also a culture in which it's a short step from doing a little more for those who are kind and generous, and doing a little less for those who don't have something extra to offer.
Bribes in this kind of setup are not likely to be purely monetary (at *most*, there might be some overpaying for something), but will happen in the forms of gifts, favors, or perhaps contributing to a pet cause. But it will still happen, that people will *favor* those who are *nicer* to them, which works out the same as corruption, just a bit more subtle and deniable than our versions.
[Answer]
## Stay away from sight and sound
Corruption only works if the baddies are secret about it. Nothing *seen* or *heard* can be hidden. So...
The closest thing to communication without sight or sound is [braile](https://en.wikipedia.org/wiki/Braille). It would be hard to convince someone to learn it without sounding suspicious *unless they were blind and already knew how to read it*.
So you have this secret society of blind people that leave messages for each other in dark caves.
## ...it doesn't really work
So you have communication, in a very limited form, with a very limited number of people. But usually communication leads to particular actions, such as putting money into someone's account, or killing/kidnapping/etc. All of these things can be heard and seen, so although a corrupt *thought* can now travel, it's still hard to carry out corrupt actions.
The only solution here is a secret army of blind/deaf ninjas, known as "ghosts", that no one can track. They are untraceable... but fairly useless.
[Answer]
**Depends on the actual mechanism of the information transfer.**
---
*I could imagine corruption if the information is accessed directly instead of **heuristically**.*
What I'm talking about here, is "*ok, you can access everything seen or heard by anyone in the past*", but if you must do it by specifying the person and the timeframe (like: John Pappagiorgio 31th of March 2008 16:30), then there is an obvious solution: Just bribe the officials in an unrelated/unexpected timeframe of situation. Nobody has the time to browse through one's entire life, so simply bribe them months earlier in the middle of the night. Then nobody will think of remembering that particular timeframe and the fact of corruption will remain hidden.
[Answer]
## Smell, touch and taste
You have written in a [comment](https://worldbuilding.stackexchange.com/questions/49309/how-would-corruption-happen-in-a-world-where-everyone-can-see-and-hear-everythin#comment138986_49309) that only sight and sound can be retrieved. That is an extremely important part of the premise. Mirror318 has already pointed out something similar.
Other kinds of communication that apply the remaining three senses would almost certainly become widespread. After all, humans value secrecy and privacy immensely. And over the centuries, this would develop into much more dynamic and complex patterns than we can possibly imagine. I don't think using such forms of communication would be seen as wrong. It would probably be seen as just as natural as using envelopes around letters is in our world.
---
I lay down on the bed. The palace was pitch dark! I knew my envoy would come to visit, returning from the Vazian chieftain's residence. He always comes in the night. He had stayed there for many days (and nights, which was the important part), pretending to negotiate something with the Vazians. Oh, his superior acting skills. I knew the public would buy the charade. They always did. They thought they saw everything.
I felt a touch against my hand. Oh, how silently my envoy can pass through the pitch dark room! His footsteps had been silenced by the thundering waves of the Atlantic Ocean roaring outside the palace. Not that he would have needed it, anyway. The man knew how to move like a cat, without a single sound. As always, there was a tiny piece of food approaching my mouth. I knew better than to even think of opening my eyes. I could sense the strong smell of **ginger** even before it touched my tounge, only to be taken back by my envoy. I proceeded to taste a **raisin**, a piece of dried **apple**, **nutmeg** and **turmeric**. Five minutes later, I had memorized a whole message.
>
> Grant trading rights to Vazians. Usual payment.
>
>
>
I tapped my envoy's wrist three times to signal that I had memorized the message. I felt the diamond, cold against my fingertips. The size was astonishing! It must be worth millions of Droas! I let my fingers slide around it in the pitch darkness. The envoy was gone now. He'd done his duty.
In the pitch darkness, I put it into the pouch. It was almost full by now. Not a sound! Each stone was encapsulated by a soft fabric. Oh, the value! My assistants would know what to do. It was not the first time, after all. I have a mine in the Rinesian Valley. My assistant would carry the pouch under his jacket this very night, to my "[diamond extraction plant](http://beyond4cs.com/faq/diamond-origins/how-they-are-mined/)." Oh, how good a business that plant is. It has been in our family for centuries. And so has our strong position in the political world of the Democracy of Griduria. We are truly loved by the people. Indeed, victory in politics goes to those who can form strong alliances.
---
Even the food is maybe too complicated. The envoy could just tap Morse code to his finger. Or maybe even the envoy is unnecessary. The Gridurian politician could just go the Vazian chieftain personally. While they are having lunch, morse code could be transmitted between the two of them by tapping their toes towards the other's feet under the table. After centuries, such methods would be as natural to humans as spoken communication is to us.
[Answer]
**Some people may choose to sever their psychic connection, or reject the concept.**
This occurs in the *Starcraft* universe with the *Nerazim* and *Tal'darim* who are not part of their psychic shared-conciousness known as the [Khala](http://starcraft.wikia.com/wiki/Khala).
**It may be impossible know the exact moment the corrupt act occurred in order to view/relive it.**
In that in order to know there was corruption, you would have to see the moment it started. If it requires watching hours/days/months of a person's life in order to see the corruption, or if the vision you get is partial (sight and no sound, etc.) then it may be possible to obfuscate it.
If a politician went on a skiing trip and in a random 5 minute window at 3am did an evil deed quickly over the phone, and went back to sleep, would it be noticed?
**Culturally inappropriate**
Culturally it may be an grave offence to view certain aspects of people's lives. If you can watch someone relive a moment of someone's private life, presumably other people can see that person has done it. Much like in *Vampire the Masquerade* the act of [Diablerie](http://whitewolf.wikia.com/wiki/Diablerie_(VTM)) is punishable by death, and anyone that does it is clouded in a dark aura that is very easily detected.
**It is possible to hide things**
Hiding parts of your life from the shared consciousness may be perfectly permissible, such as secret (but legal) details for example, a patent for a new machine or scientific breakthrough. You could then hide your shady goings-on in a similar way.
[Answer]
Corruption would just work the same.
We, in our real world, can easily and in some cases routinely talk to each other in a way that an outsider who listens in (even in the same room) gets a completely different meaning.
This happens regularly between parents when talking about something sensitive while kids are present (like, Christmas presents...); it happens in oppressive regimes when people are aware that they are in the sights of the Geheimpolizei, etc.
There is no particular need to exchange a "code" beforehand; corruption in the sense of bribery is not *that* complicated. It could be minuscule body language effects etc. together with some provisions of flooding the "communication channel" with said effects, so a routine listener had no way to spot the exact moment something was decided. Especially since you point out that getting into the memories is not automatic, but a conscious process involving effort on the snooper.
[Answer]
## Open, shameless corruption
The ruler of a territory could be *openly* corrupt. Sort of like a mafia boss. He *wants* people to fear him. His whole society is *built* on corruption, bribery and dirty dealings. He's doing business with all kinds of criminals. And if anyone so much as *tries* to go against him? They'll be killed and/or tortured pretty quickly. It's not exactly like the people can start forming a political underground resistance with ease. The ruler himself and his special forces, having all the same psychic powers as the general public, would know about it pretty quickly.
Having weapons is illegal for anyone not working for the government. Saying or printing anything negative about the corrupt ruler is banned. All political activity (except for that supportive of the corrupt ruler) is banned.
One time one of the ruler's ministers slipped up and said he wished society was different. He was fed to the pigs the next day.
All the little heroes would be killed pretty fast. The same goes for any military generals wanting to plot a coup against him. It's the ultimate terror regime. The ruler has absolute power. If anyone does or says anything against his will, they're toast. Quite a servile society. Oh, and the ruler taking or paying bribes? That's the last thing anyone cares about.
[Answer]
There are two paths this can take. One is that we argue your society is actually one giant organism, and the concept of corruption is actually moot because there is only one identity. Obviously this is not the path you want, so the second path must be the one we use: the individuals "private thoughts" are the unique identity of each individual.
In such a case, we can still have corruption, thanks to language. Language is a flexible concept. One of the interesting aspects of language is that its syntax is distinct from its semantics: the actual event experienced is separate from its meaning.
Those who engage in corruption would quickly develop a way to communicate from private identity to private identity with plausible deniability. Everyone would be able to look back at the communication later, and see it happen, but would not be able to prove that this communication was a sign of corruption.
This pattern is actually very evident today in religion. Just look at any major religious book and the vast array of interpretations we see of the same text.
[Answer]
I had a roommate from Ukraine. He said if you want something done, you pay. If you want it done correctly, quickly, and suited to your needs, you pay more. Not so much different from "premium" packages in the West. Since the culture generally accepts it (with a bit of grumbling here and there), even ubiquitous information alone wouldn't stop such corruption from happening.
It's not much different from the issue of putting body cameras on American police officers to prevent civilian shootings: as long as the prosecutors are always on the cops' side, complete video evidence is often insufficient to land an indictment, let alone a conviction.
[Answer]
In Orwell's *1984*, if you didn't want Big Brother to know something, it had to be performed outside the vision and hearing of his cameras. So Winston shielded his activities from the camera (and the eyes/ears of others).
In the world that you describe, people who desired any privacy would develop means of communicating without visual or audio interaction. Two people can maintain eye contact and speak to each other while one passes something to the other. That can be information, money, signs of affection, etc. Intimate encounters (that one desired to keep intimate) might only involve touch, the individuals would remain silent and look away from each other to prevent the act being broadcast to the entire population.
I can imagine entire categories of activities that would be performed without looking or listening.
Another idea from *1984* is *doublethink* , the ability to hold two contradictory beliefs in one's mind simultaneously, and accepting them both. I can imagine that in your world, people might develop an ability to intentionally not look. Some actions might be taboo and courtesy demands that you not look at those actions within the hive consciousness. Or people are so overloaded with information, they decide not to look at everything, so they choose to compartmentalize and overlook some activities or even people. (Similar to how families might never acknowledge dysfunctional family members, even though everyone knows about the particular dysfunction.)
[Answer]
In a very similar manner to if there was a CCTV everywhere. The difference is that it would be extremely easy to get evidence, but that may not stop corruption if it is deemed acceptable.
### Misdirection
Much like magic tricks, everything can happen in front of the eye. But what magicians, hackers, and other shady types do is that they have something that attracts attention while doing something else.
Someone attempting to bribe an official might be yelling and arguing with the official, while trying to slip some money into his pocket.
### People can't focus on everything
Certain events might cause people to simply not bother with viewing something else. A disaster like 9/11 would mean people are too glued to events, or trying to investigate something bigger to notice the smaller things.
I'd imagine a world with no privacy, sexual acts would happen much more often and not as illegal. Such actions may be distracting and a good smoke screen for corrupt actions.
### Gifts
Even in modern times, it is normal to give gifts and support. A corporation might financially support a political party's campaign. Someone trying to win a project contract might give the CEO's daughter a car as a wedding gift.
Someone could also "lose" an expensive tool like a laptop or phone as a way to hint that they'd like a specific bribe.
[Answer]
So I'm seeing a system like this: The more first hand experience a memory has, the more likely it is to find it. A sold out concert by the latest pop idol will be much quicker on the public recall than an action that is witnessed by only two people. It's not that Bob hand John an envelop of corrupt cash won't be uploaded and found by others, but unless they are specifically looking for that event, it's going to be lost in the din of my recognizable public events in both of their lives.
Alternitively, perhaps the ability to manipulate the system is some kind of special skill... like a form of martial arts... that can be trained. One can develop skills and disciplin to focus away from the link or just keep stuff fuzzy deliberately... perhaps truly grand masters of this skill can even be so powerful as to delete memories from the network... If such a person catches the memory early enough, he can keep it between the people who witnessed it.
Another thought is what about ficticious memories? People who create stories. Could a novelist reasonably convince someone that the events in question were a realistic memory of a fictional event... its for a new book we're co-authoring? What about memories of dreams? I had a pretty vivid dream where I was a Sith or Jedi of some kind, had two pink lightsabers, and was fighting Darth Sideous for some reason... would that have been shared with everyone
Another thought is some kind of deliberate impairment like being drunk or high, which will prevent memories from reliably uploading...
[Answer]
**Just because people can see and hear everything doesn't mean folks WANT to.**
Insert political polarisation into the mix and corruption can easily exist. X is doing some bad thing? Well, X's supporters would just go, "who cares, it's normal" or "that's way lesser than Y would do in the same situation". To go to the effort of confirming if a fact is true or not, they would have to hear about it in the first place, and people can be easily convinced that the news sources that oppose X are FAKE NEWS and so should be rejected without any consideration.
Indeed, people can deliberately seed the media with fake reports, so the majority of people just get tired of hearing rumours and can no longer bother trying to distinguish between what is real and what is fake, even if they easily can.
[Answer]
In a similar vein to Asimov's "Second Foundation", the corrupt parties could be genuinely convinced that they're performing a legal act. If an agent is (for example) hypnotized to believe that the bag of cash he's handing over is his boss' laundry, it wouldn't raise up the "mental flags" associated with a criminal act.
The truly corrupt activity would then be the hypnotizing - this would have to managed carefully. Perhaps you could fool the agent with simple deceit and slight-of-hand, in a way that was too subtle to be detected by a "mental glance" from an outside party.
] |
[Question]
[
The intelligent snake has all the smarts of a human, as well as the accompanying desire for luxury and refinement in their life beyond fulfilling their basic needs. What they lack is appendages, and much of our teeth.
The end of the tail of the intelligent snake is prehensile enough and can, with practise, hold a single instrument and operate it with some dexterity. A spoon or a prong would work. That would allow an intelligent snake to eat soups, stews, or anything that can be skewered in one piece and transported to their mouth. Anything in need of cutting up, or anything that would just roll around a clumsy spoon (like peas), would be inadvisable to attempt.
Snakes also lack incisors, so they cannot easily bite off a piece of something larger, unless it is soft enough to tear off.
Another option, one that seems more natural: a single larger piece of food like haggis. It would be swallowed whole, approximating the natural habit of the intelligent snake's primal ancestors. The issue is that snakes also lack molars: they do not chew, therefore they would not be able to enjoy the taste inside such a dish. It is also clear how much snakes rely on their sense of smell; thus to make a feast a proper feast to them, the cuisine must be very odorous. Which brings us back to soups, which have the advantage of evaporation.
Basically, my question is if there's any sort of dish *besides* soup that intelligent snakes can eat with a single piece of cutlery, that they don't have to chew or bite in pieces to appreciate the flavour, and that comes with a smell.
[Answer]
## All the refinement goes into savoring the experience before swallowing
Snakes are not humans and they don't have a desire for chewing or otherwise
breaking up their food into small parts. Fortunately for them, their tongues
extend a lot more and can experience the taste, scent and texture of the food before its put in the mouth.
Long gone are the days that the snakes had to quickly kill, then gobble up raw hairy/scaly prey in a hurry and then hide while they digest it. Now prey can be properly cleaned and cooked to provide a much easier to digest and more nutritious meal, powering the snakes' increased metabolism (especially the brain's energy demands). Most "prey" animals are by now domesticated and bred on farms, conveniently sized and mostly hairless, looking nothing like their ancestors in the wild.
While raw and live prey are still favored by some, they are now reserved for special occasions by snake society at large. Daily meals come in the form of a prepared and cooked prey item (or set of small ones) with variety provided by marinades, sauces and stuffing and different cooking styles. The most common utensil at the dinner table is a sharp tweezer-like thing, used to slice open skin, poke inside and hold open holes in the food to taste the insides.
Most of the mealtime is spent exploring the food with the tongue, interspersed with conversation. A small cup of water is always available to rinse the tongue if a certain flavor is too dominant. The end of the meal is signaled by the highest-ranked snake in the company picking up and swallowing their food with the rest following soon after.
The young brood that try to quickly swallow food they dislike are strictly disciplined of course.
Haute Cuisine in the snake world takes all kind of forms. One restaurant might serve specially bred mice of unique flavors, while another specializes in live prey prepared with paralytic poisons to stay on the plate. A daring few even experiment with plant-based ingredients, either to enhance the taste or even as a replacement for the animal itself.
[Answer]
**Soft But Not Too Soft**
Many foods can be eaten with just one hand and a fork. First use the edge of the fork to break apart the food. Then either scoop or skewer depending on the consistency of the food. For example:
[](https://i.stack.imgur.com/5ny3Zm.jpg)
Cheesecake (any cake really).
[](https://i.stack.imgur.com/ae0Mqm.jpg)
Potatoes (Baked/roast/boiled)
[](https://i.stack.imgur.com/ngz3qm.jpg)
Most types of fish.
All these foods have the bonus that you can chew them with no teeth. Just smoosh the food between your tongue and the roof of your mouth to get the flavour.
Anything harder must be cut up before it reaches the table. Two kitchen snakes work together to hold the food in place and cut it. It can be served either loose:
[](https://i.stack.imgur.com/hNbCOm.jpg)
or on skewers
[](https://i.stack.imgur.com/mpqbkm.jpg)
**Added Later:** Another option is to serve a joint of meat on a heavy wooden board with a big spike.
[](https://i.stack.imgur.com/6FARam.jpg)
The spike keeps the meat in place and you only need one hand to carve of a chunk to eat.
As you see there is a huge variety allowed.
**Bonus:**
On a human table each person has their own cutlery. I think on the snake table each dish on the table has its own implement. All the dishes go on the table, maybe on a lazy Suzan, and you use whatever utensil goes with whatever you're eating at the moment.
Some dishes arrive in one piece and require two people to eat. Different dishes have different symbolic meaning attached to them. Some are holiday throwbacks. The most well known is eaten when one snake proposes marriage to another, or maybe at the wedding party. Tradition dictates they serve an entire animal on the table. Only instead of one snake swallowing the whole thing, they work together to cut it into pieces and share the food.
[Answer]
Blenders.
Everything gets blended, either together or separately. The snakes can spoon the pastes and drink the liquids fairly easily to get the flavors they want. The only problem is the blender itself. It can be handwaved or made super simple, like the grindstones in early grain mills.
Meat and other solids could still be left intact or cut into smaller pieces. In pieces, they could be dipped into the "sauces" from the blender. Think fondue.
[Answer]
The first thing is that your snakes want to eat a lot of their food cooked. Cooking is basically partial pre-digestion, which enables the eater to absorb more nutrition for less energy spent digesting and is vitally important to keeping up the calories that let them be smart. In particular, this could prevent the notorious post-eating torpor of reptiles.
The second is that your snakes are still beings that are used to swallowing food whole, so chewing is less important. Give them food in chunks.
The third is that your snakes are probably obligate carnivores. They need their meat. Vegetables *might* be edible if they were given treatment that made them basically digestible as meat.
So meat is chopped up into bite-sized chunks. Like Chinese cuisine, even if the reason is enable swallowing rather than conserving fuel. The chunks would be bite-sized -- and they have pretty big jaws. They could then use a prong to stab the pieces and bring them up to their mouths to swallow the chunk whole.
[Answer]
I am not sure if this would be acceptable for OP or what OP really wants, but since snakes still can swallow:
I think **sausage** and **sushi** would be nice for a bite or swallow size. If the snake is able to eat vegetables and the like, I think of **tofu** and **pasta/noodles** too, and **omelette** too since snakes like to eat eggs, or if you want a more unique one maybe **balut** and **century egg** for example. Regarding smell, many types of spice or sauce can help enhance it.
You can also marinate or soak tough meat to be more softer like using lemons and milk products.
**Regarding cutlery or utensils**, I agree with you they can wrap their tail around the handle to manipulate it, but I think it will be crude and it probably look awkward in motion too for certain angle, especially regarding cutting tool, beside I think they can only apply same pressure rather than focused pressure when wrapping, unless the tail tip is free to use the thumb like pressure (like the image below) but it may also take lots of the tail length to doing so, and I think they would have awkward time to adjust the tool positions to some degree, so I suggest to make hand tube (think of pirate hook hand, scissor, pata, etc) as the handle to let the tail tip slip inside to have better tool manipulation and better pressure manipulation too, I suggest the tube reach to near the blade tip if want a more tip type of pressure, while not sacrificing the snake body length and i think the body can feel more relax, its up to you to still give protruding handle tip or not like common utensil handle, since it can also give stability to it and new motion, or make horizontal handle like katar or hand saw handle at least for slicing motion type, this assuming they don't know modern or futuristic artificial/prosthetic hand technology, otherwise use that instead.
**Here are some images to help imagine it better** but instead of just hook it can be the fork, spoon or knife in it, while also applied what @renan suggest as multipurpose or Swiss knife kind of tools, at least to keep the food stay still for example a hook or [jite](https://i.pinimg.com/originals/3c/e2/db/3ce2db350915bd0c1d3c16e6fd895caa.jpg) type of crossguard to pin on the food while cutting.
[](https://i.stack.imgur.com/C2Hn3.jpg)
[source](https://www.quora.com/Why-did-Captain-Hook-the-pirate-have-a-hook-for-a-hand-What-possible-utility-did-that-provide)
**scissor**
[](https://i.stack.imgur.com/TMpgv.jpg)
[source](https://commons.wikimedia.org/wiki/File:Scissor_01.jpg)
**pata**
[](https://i.stack.imgur.com/iWkOR.jpg)
[source](https://en.wikipedia.org/wiki/Pata_(sword))
**and horizontal handle for specific slicing/cutting motion** (just focus on the general handle, not the blade itself or the overall shape, also ignore how wide it actually is, if it's not clear enough that don't take this image literally)
**handsaw**
[](https://i.stack.imgur.com/64sTh.jpg)
[source](https://en.wikipedia.org/wiki/Hand_saw)
**katar**
[](https://i.stack.imgur.com/xzo8d.jpg)
[source](https://en.wikipedia.org/wiki/Katar_(dagger))
[Answer]
**Mashed Potatoes**
They can smell quite nicely, you don't really have to chew them and you don't need two arms.
[Answer]
You could consider that they eat what real snakes eat, but in more refined ways. I am thinking, for example, of ways to eat a whole mouse in a "refined" way. Serve them in fancy containers? Catch them with a very sharp fork?
I think the snakes would prefer to keep a more natural diet, and establish cultural norms around that.
[Answer]
Caviar is “luxury and refinement”. Maybe caviar on top of a deviled quail egg. It’s pure protein and fat, it’s black and it’s evil sounding. Would make Martha Stewart proud.
<https://www.marthastewart.com/910523/deviled-quail-eggs-caviar>
[Answer]
I reckon they should use a spoon-fork-knife combo! It gives them a spoon for soups, a knife for cutting and a fork for lifting food :)
[](https://i.stack.imgur.com/w0bIn.jpg)
For example you can get them here:
<https://www.louis.eu/artikel/origin-outdoors-titan-spork-spoon-fork-knife-combo/60992024>
[Answer]
**A vibrating prong**
Part of the fun of eating for a cold-hearted snake is to see the struggles and death throes of the prey. If the food is cooked or otherwise prepared, it will presumably be dead. This removes a lot of the enjoyment.
A vibrating prong will give the appearance of life. It will act very much like a cat toy but combined with nutrition.
**A restraint cutter**
For food served live, it will need to be tied down to prevent escape. The snake can first inject venom or constrict their prey and then, when ready to swallow, cut the bonds.
[Answer]
Did you know that there are humans who, for different reasons, have only one functional hand?
And if you did, did you also know that they can live completely normal lives? If you imagined otherwise, please inform yourself about ableism. Thinking that one-armed people would only be able to eat soup is an example.
Necessity is the mother of invention. And if real humans can be inventive, so can your intelligent snakes.
[](https://i.stack.imgur.com/7XFxq.jpg)
] |
[Question]
[
Recently I've gotten interested in the planetary romance genre and the idea of a sword, sorcery and spaceships genre.
So here's the dynamic is basically something like this.
There is a star system with three habitable worlds is analogous to Earth, Mars and Venus.
The vast majority of the population lives in a state resembling premodern times as impoverished peasants and serfs. The average person has a somewhat advanced understanding of astronomy.But beyond that they know little else and owning a motorized tractor is considered affluent to them.
Technology and science is fairly restricted as well due to social and religious strictures that underpin the caste system. With technology more or less being in the hands of middle caste craftsmen, mystery cults and noble families.
But the hinge that everything here turns on is that this civilization of techno-barbarians still operate fairly sizable spaceships and space elevators that facilitate travel between the three worlds.
Microchips and vacuum tubes are, as far as I can tell, not something a local craftsman can just make in his workshop. More importantly, advanced technology on top of requiring extensive supply chains to operate, also requires a fair bit of know-how, mathematics and computation to operate.
Their engineers are for the most part scavengers, but at the same time this civilization is old enough that said engineers would need a reliable method of replacing broken parts otherwise entropy would've claimed everything by now.
Compare that with say, NASA who sometimes have to scrap projects because a manufacturer that made specific parts went out of business.
The advanced technology being utilized as well is somewhat what I'd term near future rather than far future. More the Expanse in spirit than Star Wars is how I'd describe it(with some exceptions). Meaning there's no force fields, anti-gravity, replicators, and handheld laser beams. There are some fusion reactors, but most things run on fissiles and advanced biofuels.
My question is basically how is it that these techno-barbarians can still travel between worlds, yet at the same time remain scientifically and technologically backwards?
[Answer]
## Frame challenge: Neither main constraint need be necessary. The technology is self sufficient but also self limiting by means of its control system
>
> Microchips and vacuum tubes are, as far as I can tell, not something a local craftsman can just make in his workshop.
>
>
>
Reverse this. There are a very small number of surviving advanced AI-governed fabrication units that can make damn near anything with the press of a button,given time, and some basic materials.
But they are permanently set to Repair mode, allowing only replacement parts to be made. (Plausible excuse: they're logged in on a service technician's account).
The size and form and details of operation of the fabricators can be tweaked to suit your exact setting.
The fabricators are networked and if one genuinely fails, the others can build parts to repair it.
The fabricated parts have encrypted security keys and self checks and and are useless for other purposes. The fabricators themselves commit suicide by wiping their security certificates if tampered with.
>
> More importantly, advanced technology on top of requiring extensive supply chains to operate, also requires a fair bit of know-how, mathematics and computation to operate.
>
>
>
No. The fabricators and spaceships have some terminals with ChatGPT-47. It, much like the fabrication units it is networked to, only helps them do basic maintenance, replacement and navigation tasks, but makes them effortless.
As an author, pick the number and type of all the available spaceships and other doodads, as well as fabricators.
Anything up to that number is effortless, anything beyond is impossible.
Physical possession and/or sabotage of the fabricators is, of course, a geopolitical consideration of the first order.
A chieftain who can secure and keep one can be assured of ships bringing him wheat, olives, fruit, cattle, slaves, and valuable furs on a regular basis.
Of course, it's techno-Ecclesiastes; there's lots of oil and honey and concubines, but there is always nothing new under the sun, not even on Mars.
[Answer]
This is basically the premise of Warhammer 40,000. There are two approaches to handling it, and Warhammer demonstrates both.
* You can have a secret society who are the only ones with requisite knowledge. Thus the techno-barbarians maintain the ships by having a non-barbarian sub-group that does so.
* An AI bridges the gaps in knowledge. The barbarians conceptualize this as "magic". They know that certain actions (rituals) are sufficient to activate various functions of the spaceship, but they have no idea why it works (magic). In reality, it works because the AI is able to do the complicated stuff, but the users no longer understand the AI and consider it a "spirit".
The first one I consider boring, because in its strong form it defeats the point of the premise and undoes any dramatic tension. Incidentally, Warhammer has a weak version - there is a secret society that knows the *rituals*, while the general public does not know even those. Therefore almost *nobody* knows how it actually works.
The second one is more interesting. Generally systems are designed so that knowledge required to build the system is more than that required to operate it. This way you can have your top engineers focus on building the system once, while less brilliant technicians can run it thereafter. Therefore, simplified operator's manuals would be more abundant and better known among the ancestors of your barbarians. The parts of these that are *necessary* would be preserved over time, because if someone tries to remove those steps, the "ritual" will stop working. But over time people might add unnecessary steps, especially if there is a dogmatism to how the rituals are taught and regulated.
To be credible, your barbarian society must have some sort of aversion to critical thinking in the context of the rituals. Otherwise they will, over time, apply simple logical thinking to gradually re-discover the technology. The straightforward way is to introduce a religious organization that highly discourages innovation. Or you could say that your story is set at a time when this critical thinking has not *yet* developed.
You could also say that the technology was deliberately obfuscated as a way of protecting intellectual property and deterring reverse engineering. This works if the original creators lived under a corrupt military-industrial complex with significant regulatory capture. Normally the logical thing is to make such starships as transparent as possible, to maximize the possibility of field repairs. But of course with a profit-motivated manufacturer, perhaps field repairs are a lower priority than protecting trade secrets.
[Answer]
# Vacuum tubes can probably be made in a workshop.
I'm hardly an expert, but I'm pretty sure that vacuum tubes do not require nearly the level of precision that microchips do. Fundamentally, all you need is glass, metal wires and rods, some sort of pump to remove air from the tube, and the knowhow to put it all together - and if you can evacuate the air from the tube simply by heating it up to just below the melting point of the stuff you made out of and then sealing the hole, you may nor even need the pump.
[Answer]
Time-pirates. Civilization broke down because of time travel. People from the future keep going back in time to steal stuff. The zero-sum game creates a slowly fading culture as the knowledge and machinery dissipates. At a certain technological density, meaning time-jumps of a certain distance, time travel tech itself breaks down. Thus at a certain point, no future raiders appear and civilization can begin to advance. But then that civilization re-acquires time travel, the cycle repeats. This ultimately reaches an oscillatory steady state.
[Answer]
Two possible answers
**Trade** - They trade with others that can produce said technology for them. They don't care to know how it works because that is beneath them as warriors. They just need to be able to use it. Any technological race can produce simple enough controls for a knuckle dragger to use. The technological race might be few in number but so vital for the barbarians that they are treated with utmost respect. The barbarians might also be vital to the technological race as they act as protection for them as well as supply important materials.
**Slaves** - Skilled slaves are lower in class than warriors but are still important to society. The slaves produce the required technology and are protected in return by the warriors allowing them to live normal peaceful lives. The key to this is the size of clans. A few hundred people can't produce things like microchips as it requires too many specialists to make from the production of the raw materials to the design and manufacturing. You need clans to be much larger to support the level of specialization required for that technology.
[Answer]
I suggest a hidden society that provides the know-how and production capabilities while also enforcing the tech limitations on the majority.
This hidden faction has the ability to render any or all ships they provide inert at any time and so the people using those ships have strong reason not to exceed whatever boundaries have been set.
Now, the question becomes, why does this hidden faction remain hidden, why not just take over and make everyone else slaves.
[Answer]
A ginormous class divide results in an incredibly wealthy upper echelon of people with access to all kinds of advanced technologies, and a poor, ignorant underclass. These dregs of society are used for all manner of physical labour and warfare, and therefore man the spaceships.
Alternatively...
Frame challenge: they don't.
They're a relatively low-tech civilization that commandeered an alien vessel that landed on their planet. Instead of taking it apart, they put their best warriors on it, had them slowly learn the controls (or maybe the aliens taught them how to do it before the barbarians kill them (or something else, you can think of a million different story options)) and then take to the stars. They then steal more ships from aliens, bring them back to their home world, and begin transporting people between the worlds of their system. Instead of repairing the ships they have, they venture out and steal new ones whenever they fall into disrepair, distantly reminiscent of vikings (not to say that vikings didnt repair their own ships, the comparison is just due to all the plundering) .
[Answer]
## Spend all of their resources making spacecraft
[And leave no more for their own citizens](https://en.wikipedia.org/wiki/Era_of_Stagnation). As long as it's a slightly more extreme version of the Soviet Union during eras of starvation, you should be fine. Have a small caste of technocrat elites run the place, some engineers sit in the equivalent of a middle class, and the plebs figure out which tree to eat.
[Answer]
There's two main options:
1: Secretive Guilds - The Spacecraft are maintained by a Guild of sorts. Apprenticeship is long and difficult and all members are sworn to absolute secrecy. You can have some form of Philosophy about being pacifistic 'We only move people and resources, we do not fight and if we reveal our secrets, the blood will be on our hands' or at least, non-aggressive. This is probably your best bet.
2: People only know what they *need* to know. If you are struggling to grow enough crops to feed yourself, your family and just enough to sell at a market - you aren't going to have the time/space/mental bandwidth to learn about Space Travel. The more oppressive (either human or natural oppression) an individuals surroundings are, the less they have to worry about high/deep/thick concepts like Space Engineering.
[Answer]
I had a similar concept with a very warrior culture alien race I worked on. To give them a mindset that was more alien, this alien's culture actually treated battle scars and wounds as a symbol of shame, and actually went to great lengths to make sure that any battle scars were never shown. The reason for this was that a scar or injury symbolically meant that they were a poor warrior, since it showed that they had made a mistake that allowed an opponent to injure them. A true warrior, according this culture, would make no mistakes.
This backwards mentality resulted in the development of advance medicines, to allow for the healing of the body in such a way that scars and other missing body parts could be heeled to hide the taboo mark of imperfect battles. The philosophy also lead to developing strong engineering and maintence skills, since small blemishes upon weapons meant that the enemy had touched them in combat. A chink (in one's armor) at dawn was a scar at dusk, according to them. So their weapons where constantly maintained. Their warships were often considered to be some of the prettiest in the interstellar community because they always looked factory fresh and had that new battleship smell.
This also lead to their major weakness, in that they were slow to react. After sustaining minor battle damage it was often common for a ships captain to find a place to hide and begin repairs... on a ship by anyone else's standards was combat ready and simply had a dent. However, once they joined the battle, they were ruthless and unrelenting. It wasn't shameful to receive battle injuries, so long as the marks of the injuries were not shown... especially to the enemy. If their military policies could be scaled down and summed up by a chess game, they were very good at playing fast games which resulted in victory in a few turns... however, they struggled with the long term game, because they had trouble wrapping their heads around sacrificing a pawn for a checkmate. Whereas humans were some of the galaxy's masters of pyrrhic victories... inflicting upon their enemies unsustainable victories that would result in losses over the long term.
In other works of fiction, some aggressive races never developed the tech, but stole it from oppressive alien invaders that they overthrew. In Star Trek lore, one recurring alien race achieved warp capable space flight in this manner. Before their first contact with humans, they were conquered by an alien race, known as the Hurq, that wished to enslave them. However, the Hurq underestimated the primitive alien's ability to grasp the concepts behind the advanced space flight and soon found themselves on the losing side of a slave rebellion after the aliens learned and mastered their tech to such a degree that they could manufacture the technology themselves. The former slaves ended up fighting in such overwhelming force, that by the time humans were capable of space flight that could reach the territory, that not only had the Hurq empire fallen, the Hurq as a species was extinct and the humans had to open up relations with the former Hurq slaves, known as the Klingon (It was so thorough a victory for the Klingons, that it's still debated if the Hurq were real or a myth. There's little evidence of their civilization at all.).
[Answer]
# Scavenging
Have the setting be the ruins of a post-collapse civilization. This civilization built a [Niven Ring](https://en.wikipedia.org/wiki/Ringworld) before their fall. The ring [has since broken enough](https://worldbuilding.stackexchange.com/q/149706/83464) that it is hazardous to live there, but it is also full of huge amounts of usable technology. Scavengers brave enough to navigate the broken ring can then sell technology they find through [semi-criminal resellers](https://starwars.fandom.com/wiki/Unkar_Plutt).
This civilization could also have built several other useful things, such as having terraformed several planets and built space elevators on them. (It seems unlikely that a single star system would have three natively habitable planets and equally unlikely that a civilization of this level you describe would be able to terraform planets themselves.)
One caveat to this premise is that some things cannot be fixed if broken. Space elevators seem like the most fragile piece of infrastructure in this situation. You likely need another means of getting into space, as a space elevator is much easier to destroy than it is to build (example: <https://www.youtube.com/watch?v=huRmvG3zRpg>).
[Answer]
**Hidden AGI**
All the technology is ran by an artificial intelligence that determined the best mode of peacefully living alongside humans is to maintain illusion of "swords and sorcery" world. It avoids presenting itself as deity and maintains the illusion that humans are in control. No Matrix-style control over humans is necessary, most people can be easily misdirected and human intelligence/perception is still genuinely useful in many ways.
[Answer]
**Just give them one really powerful Clarketech and nothing else**
I'm not sure how willing you are to put Clarketechs into this setting, but they are pretty amazing. I'll go over how you might go about achieving space travel in this setting, then I'll try to address how they might maintain the infrastructure for doing so. I know you said the people in your universe have fission power an biofuels, but other than spacecraft propulsion, what are they powering with it? Do they have electricity? My advice would be to say no, they don't, but they do have this thing that lets them send sealed metal structures between planets. There are various means I'm sure you could think of for a Conan-the-Barbarian level civilization to do this (maybe that's not how you imagine them, but your use of the word 'romance' in describing it made me picture burly shirtless men and bodice-clad wenches, so that's how I'm imagining them now; John Carter of Mars vibes). The trick here will be to address how these primitive overcome the difficulties of space travel. Those difficulties are things like these:
* Requirement to escape gravity well of current planet or body: I know you said they don't have anti-gravity, but if they did, they could shrug off this barrier, and focus on having insane, janky, cobbled-together spaceships that don't need to withstand the rigors of launch and can be basically as massive as they want.
* Requirement for high acceleration to overcome vast distances in reasonable amounts of time: Maybe interplanetary travel just takes a really long time for your people, and so they don't do it lightly. Then again, in the age of sail, people would spend years of their lives traveling between locations and often never went home again. The people of this universe, you said, are knowledgable about astronomy, however, so they ought to be able to use orbital physics to make their trips as efficient as possible. You might consult NASA's *Basics of Spaceflight* if you haven't already, to learn about gravity assists and Hohmann transfers and all the rest, (solarsystem.nasa.gov/basics/). Really, once your free of a planetary gravity well, space flight is pretty cheap, it just takes math and a lot of time. If your people had something like anti-gravity, then they could essentially skip to the interplanetary flight stage, using gravity as a tool, and only as needed, and if they plan and plot their voyages right, they can minimize their time spent in outer space. And that brings us to our next point.
* Requirement for precision in course plotting: Never mind about precision in engineering. If you have something like anti-gravity, or never have to bother with planetary gravity wells at all, your ship could just be a bolted-together junkyard in space, as long as it's airtight, blocks radiation, and has some means of propulsion. What's important is that you can plot an accurate course between bodies. This takes math, and good theories about gravity and such, but it need not necessarily require computers or electricity. Maybe every interplanetary ship just has a navigator who has trained their whole life for the role, or maybe they just brain it with pen and parchment before they embark, knowing the motion of the heavenly bodies, and do spaceflight without computers like the gods intended. In our world, the people behind interplanetary craft plan their missions for years ahead of time, and those plans include flight courses and how they are going to get the momentum they need when they need it.
It's sounding like the answer to spaceflight in this setting would be something like anit-gravity. That said, you have already provided a somewhat compelling reason why they might not need it. You mentioned that they have space elevators. I'm not sure what type of space elevators you have in mind, but these generally change the game in terms of space launches. The top of a geostationary space elevator is moving at orbital velocity, meaning you can just push your spaceship off from it and it will already pretty much be in orbit of the planet. These structures are absurdly long/tall however, since they have to reach the altitude where the angular momentum reaches or exceeds orbital velocity, and so they might not be feasible for Venus due to its extremely slow rotation. Even just for planets spinning as fast as Earth and Mars, they have to be many thousands of kilometers tall, as in like wrap-around-the-earth-several-times long.
Returning to your original question (finally), I think you should be asking how they maintain their space elevators. How they maintain their ships is easy: they just bolt on more pieces of metal and hope, and then just only blow up sometimes. Space elevators are problematic because they require absurdly strong and highly available materials that are unknown to modern science, hence we haven't built any yet. But if you just gave them some kind of Clarketech/magic that lets them build absurdly tall towers, that solves that problem, because, as they say, "a wizard did it." If that were your one Clarketech, think of what else they would use it for. You see impractically tall towers in sword and sorcery type fantasy all the time. If some of those were "space towers", for the express purpose of delivering people and goods between ground and orbital velocity, it wouldn't even be that crazy, since space towers/elevators can only really be built on the equators of planets.
So, let's say your one Clarketech is this vertical structure integrity thing. You have a primitive civilization who tells the tales of how their ancestors built those towers to reach the heavens, which allowed them to travel between worlds (book cover ideas in the style of Roger Dean are flooding through my mind), and you maybe have highly specialized people who go around upkeeping these structural integrity fields/spells with their magic/technical expertise. Are they wizards? Up to you. Who do they serve? Are the space towers owned by kings or nobles, or are they more subdivided because of how absurdly tall they are? Does everyone with status have a super tall tower, just that only those on the equator bother going above the atmosphere? All questions for the worldbuilder to answer.
Good Luck
[Answer]
What if there are sentient machines which have been tasked long ago to protect, care, and feed humans? After a while they decided the best thing to do is to keep them reasonably backyards, providing them with certain tools and parts as needed but using creative ways to keep the humans in the dark? I know it sounds like the the Warhammer secret society but the difference is that even if there is a priesthood interacting with the terminals, the AI is deciding if the hairless monkeys should have access to something or not.
The fact there are space elevators, which happen to be maintained, and spacecrafts only mean that the metal overlords decided they planets need to stay connected even if it is in a kind of Pre-Black Ships Feudal Japan way. In fact, most people would not even be aware there are spaceships out there, and only see space elevators as ways for the rich folk to perform their burials (the serfs get buried in disease-infested pig shit that is their main source of nutrients while the better people get launched at low orbit so they can spin for a while and then reenter and burn). Only few people, who usually do not mix with the plebs, are involved in the interplanetary trade and diplomacy. As said by others, even these people only have enough cargo cult training to think they are operating the machines.
The sentient machines, meanwhile, keep the monkeys under control so there is never too much killing or deceases unless there is a condition they need to correct using that. Heck, they can even brew and unleash a T-Rex or dragon to put the fear in the hearts of the uneducated masses.
[Answer]
## You forgot the Sorcery Part
The OP mentioned that his setting falls into the
>
> sword, **sorcery** and spaceships genre
>
>
>
This means that the spaceships need not be controlled by microchips and computers at all. Instead they are magical constructs more akin to golems. The reason your craftsmen are able to make ships is not because they are able to hammer out highly advanced technologies in their forges, but because they are able to hammer out ships that are exactly as technologically advanced as any pre-modern naval ship. Then it is the job of powerful enchanters to turn your weird looking construct into a magically animated thing that can carry you through space.
As long as sorcery itself is some natural ability possessed by only a handful of people or requires some kind of rare unobtanium, then your space barbarians will still have to do most things without machines because your civilization's total "factory" capacity is limited by the number of enchanters or amount of unobtanium you have.
[](https://i.stack.imgur.com/1jR3O.png)
## Or you could go with tech-mages
If you want your spaceships to feel more like real ships, then it could be that your technology is actual technology that works like computers and stuff, but it is magically crafted; so, instead of a multi-billion dollar, high tech electronics factory, you could have powerful artificers who can magically shape materials down to the atomic scale hand-crafting each computer terminal and rocket engine.
Either way, magic lets you have a cottage industry based society that can make things that we muggles can only do with big expensive factories.
[Answer]
Slaves. Just slaves. Over the past thousand years they cultivated their own slave race. Beaten into submission only the most obedient meek and clever survived. Creating their own subculture and ways to influence their masters by subtle hints and sweet words.
] |
[Question]
[
If there were a black hole orbiting an inhabited planet, with the gravity of a typical moon (e.g our moon, orbiting a similarly weighted planet to ours), what practical differences would arise when compared to a normal moon (such as it affecting the atmosphere) and would there be a viable way to harvest energy from it?
[Answer]
>
> what practical differences would arise when compared to a normal moon (such as it affecting the atmosphere)
>
>
>
Almost none.
There'd be no moonlight under normal circumstances, which means that no life would have evolved to make use of that, and you wouldn't find any moon-rocks on Earth as there would never be any impacts as such.
There'd be some hazards associated with an accretion disk forming, because those can get pretty hot. If the planet has an atmosphere though, you can reasonably assume that the accretion disk is either absent or fairly small and benign.
>
> and would there be a viable way to harvest energy from it?
>
>
>
Not trivially, though you can do tricks with rotating black holes that have what is called an [ergosphere](https://en.wikipedia.org/wiki/Ergosphere), where if you enter the ergosphere travelling fast enough then you can steal a little bit of the angular momentum of the spinning black hole and leave a little faster than when you went in. Extracting energy from this is tricky, but using it as a boost for spacecraft should be a bit easier.
Because the radius of the black hole is so small, its rotation would not have any additional tidal effects on Earth, and it would not have undergone tidal locking in the way that the real moon did.
---
*edit*:
Just to note, the evaporation timescale of black holes is *long*. Even a hole as small a billion tonnes will take over a *trillion* years to evaporate, and the moon is a hundreds of million times heavier than that. The relevant [wikipedia page](https://en.wikipedia.org/wiki/Hawking_radiation#Black_hole_evaporation) has the full gory details, though the important thing is that evaporation time scales with the cube of the mass of the black hole.
Don't worry about your local black hole exploding and destroying your planet... think more about the fun fireworks when the local sun finally enters the red giant phase of its life after a few billion years, and its photosphere expands to cover the orbit of your planet...
---
*edit 2*:
There is, almost but not quite inevitably, [an XKCD about that](https://what-if.xkcd.com/129/) (or at least, a what-if). It doesn't consider extracting energy, but the rest may be of interest. To summarise: looks boring, has a near-undetectable reduction in the heating of the Earth.
[Answer]
>
> would there be a viable way to harvest energy from it?
>
>
>
Since gravitationally this is almost identical with our situation, there is a way of harvesting some energy - the black hole would produce tides of the same amplitude we are used to. [And that can be used to generate electricity...](https://en.wikipedia.org/wiki/Tidal_power)
[Answer]
If our Moon were swapped by a black hole of equal mass, there would be no gravitational distinction felt on Earth. We would miss out on Lunar eclipses and solar eclipses would probably make the Sun look like a ring while in "totality."
Creatures that use the light of the Moon phases would get messed up and may not breed (theoretically, this is when corals know when to breed).
It would be pretty dark at night too.
Throwing stuff at the Moon massed black hole would release energy as the matter is ripped apart before it crosses the event horizon. However, to collect that energy, you would want to surround the Moon-hole at a "safe" distance. I don't know if that would be worth it.
Another problem is that a black hole that low in mass would be relatively short lived. Black holes evaporate. A Moon sized back hole wouldn't capture enough matter to offset the evaporation. Eventually, it would decrease in mass enough to not be able to hold itself together and go boom. That would be a bad day.
I would say that it is unlikely to be found naturally existing. Since any low mass black holes created in the big bang would have already evaporated away.
That means that super science would be needed to create one. I think that any science that could create a Moon massed black hole wouldn't need the energy generated one.
[Answer]
Others have already answered the boring part of this question (= very low impact on earth as we know it, apart from the uses that biology and human culture make of the moonlight). I won't repeat that. I'm going to answer the fun part of the question: **How to harvest energy from it**.
First of all, a moon-mass BH is tiny. [Wikipedia](https://en.wikipedia.org/wiki/Schwarzschild_radius#Parameters) puts it at 0.109 millimeters. That's big enough to interact with macroscopic objects, but tiny compared to human made space hardware. As such, I see two distinct ways of harvesting meaningful amounts of energy from it:
---
#### Option 1: The spacecraft slinger
1. Build a long (= tens to hundreds of kilometers) beam with loads of tensile strength.
2. Send it into orbit around the BH where the tidal forces on it are still manageable. This orbit will have a radius that is also in the range of tens to hundreds of kilometers. Put it into rotation such that the same end always points towards the BH.
3. Have a docking station for spacecraft at the point where the orbital speed of the beam structure matches the escape velocity.
4. Have two escalators starting at that point, one going outwards for the spacecraft, the other one going inwards for small weights.
5. Each time a spacecraft docks at the spacecraft slinger, it brings a matching weight with it. The weight is moved inwards to the very end of the beam, the spacecraft is moved outwards far enough that the orbit of the entire structure remains at the same height above the BH. Then both, the weight and the spacecraft are released at the right moment to send the spacecraft on the intended trajectory.
This is essentially a free floating space elevator that operates in a much tighter gravity well than earth's, and that operates at a much higher angular speed than earth's rotation. These two features make the design much more easy to build. However, the weights are required because the massive rotating body at the center of the gravity well is missing.
Since the beam reaches quite far down into the potential well of the BH, the weight can be tiny compared to the spacecraft.
As an added bonus, both the weight and the spacecraft lose potential energy as they are lowered to their respective release points (well the weight first needs to be elevated against the centrifugal force, but that energy is more than regained as the weight moves further into the gravity well). As such, **the operation of the spacecraft slinger actually produces energy**.
Obviously, the weights will accumulate in a belt of highly elliptical orbits around the BH below the lower end of the elevator. In the long run, this will enclose the BH into a cloud of Kessler debris, and that cloud will gradually heat up as collisions become more and more frequent. This won't pose a big threat to the elevator though, because a) the collisions will tend to circularize the orbits of the fragments, b) considerable energy is lost by grinding down the fragments, and c) the weights only barely had the energy to touch the lower end of the elevator to begin with. However, this Kessler cloud will make the realization of option 2 much harder.
---
#### Option 2: The Dyson Power Plant
1. Build a spherical megastructure around the BH.
2. Line the inside of that megastructure with generators that can turn hard EM radiation into electricity.
3. Add a device that is able to aim millimeter sized bullets precisely at the BH.
4. Add some doors to the sphere that can be opened to provide a tiny propulsion to the sphere to keep it centered exactly on the BH.
It does not really matter, what those bullets are made out of. Only the denser, the better. Each bullet will accelerate to relativistic speeds as it falls towards the BH. When it hits the BH, most of the bullet's mass will move right past it. However, all of the bullets mass will be deflected towards the BH, and will subsequently crash into itself (the bullet will actually behave like a giant cluster of ping pong balls, not like a rigid body; the energies involved are much too high for inter-atomic forces to play a significant role). This will instantly turn the bullet into an extremely hot plasma that emits loads of gamma rays, allowing the surrounding sphere's generators to do their thing. The plasma won't retain enough kinetic energy to get back to the Dyson sphere, it will fall back onto the BH until it turns into a tiny accretion disk that continues to produce hard EM radiation.
It would be possible to run this gigantic power plant without entirely enclosing the BH in a Dyson sphere, but that would have two problems: 1) Most of the produced energy would be lost to space, and 2) if there are people living on a planet nearby, they might not be too happy with the effects the intense gamma radiation has on their atmosphere. Or with the effects that the UV light has on their eyes. It would be like a continuous atomic explosion in space. Of course, it would be possible to build a Dyson ring that ensures that the BH is never visible from inhabited planets. Nevertheless, astronauts in spaceships might not be appeased by that.
[Answer]
I just want to add that on top of all the other answers explaining the tricks of light and how to extract energy, eventually civilizations in the planet will figure out the existence of the black hole, and quite early too (around Isaac Newton's era, if they have a similar history to ours).
They might send rockets there during their early space age with potentially disastrous results. You see, the gravitational effects **ON EARTH** are indistinct from an actual moon, but close to the hole is something else entirely.
The gravity pull of a body decreases with distance from its center of mass. But for planets, if you dig into their mantles, there is a shell effect that reduces gravity because there is less mass below you and more mass pulling you up. The result being that the largest pull you get is when standing on their surface. That said, if the radius of your "moon" is smaller than your hand...
Remember that gravity becomes 4x stronger every time you reduce your distance to the source by half. The radius of the moon is just a little less than 231 greater than the event horizon of the black hole in the question (I may be wrong by one or two orders of magnitude, but at this level it doesn't matter much). So if a rocket passes even a few meters close to hole, the rocket will be torn apart and its particles will be accelerated to near light speeds.
On the bright side, scientists can use the black hole to achieve awesome slingshot maneuvers. Just aim to a few hundreds of kilometers away from the black hole and it will be like having Jupiter on our backyard. They could send missions to outer planets and beyond much sooner and at much less cost.
On the dark side, if you make a mistake and the rocket passes too close to the black hole, the rocket's disassembled molecular or even subatomic parts might be coming back towards the Earth at relativistic speed, causing more damage than huge meteor strikes. Our very first mission to investigate the black hole could also be our last.
By the way, that is considering plot armor. It might be that asteroids such as the one that did the dinosaurs could take a gravity slingshot from this black hole too, hitting the Earth at thousands of times faster speeds than they would otherwise. This has the potential to vaporize our planet. Since there are literal geological eras of heavy asteroid and comet bombardment on Earth and on the Moon (consider all her craters), it is more likely that the Earth won't even exist unless the black hole has appeared relatively recent.
[Answer]
The radius of a black hole is related to its mass by the simple formula R = 3\*M, where the mass M is given in units of the Sun's mass and the radius R is the radius of the black hole's event horizon given in kilometers.
The mass of the Moon is about `7.34 * 10^22 kilograms`
The mass of the Sun is about `1.99 * 10^30 kilograms`
The mass of the Moon is therefore about `4 * 10^-8 in Sol equivalents`
The black hole therefore has an event horizon radius of about `12 * 10^-8 kilometers`
If I did the arithmetic correctly, this is about 0.012 millimeters. For perspective, it's a bit less than the size of a human hair. An object of this size probably would not result in any detectable disturbance in the light reaching earth.
Anything that came within that (very small) radius would be unable to escape the gravitational well, it's true. But I think we could spare the odd bit of interstellar dust. :)
If the Moon were replaced by such a black hole, the gravitational effects you experience would be unchanged so long as you remain at a distance greater than or equal to the original radius of the Moon. However, since the gravitational force experienced depends on the distance between the center of masses and is given by `F = G M1 M2 / D^2`, the gravitational force (and therefore the gravitational acceleration) experienced will be greater as you move in closer than the original radius of the Moon.
Since current rocket designs carry only barely enough fuel to achieve escape velocity starting at the surface with one earth-normal gravity (9.8 meters/sec^2), it is interesting to calculate at what distance from the microMoon you would experience that same gravitational acceleration.
The things you might do to harness those effects here on earth would be the same things we can do with the Moon's gravitational effects. Up close and personal might be a bit different...
[Answer]
A few points that haven't been raised yet:
1. The moon-sized black hole would shelter Earth ~negligibly from impacts (e.g., Late Heavy Bombardment) probably increasing the duty cycle of extinction-level events, possibly accelerating evolution but also shortening the timespan for intelligent life to become space-faring and escape oblivion.
2. The same ~centimeter sized debris from the tails of comets that produce our meteor showers could be gravitationally slingshotted from the black hole towards the Earth with potentially catastrophic effects. This could be expanded upon.
3. If the black hole's spin axis aligns with the Earth, we'd be safe. However, if the spin axis were to point to Earth (occasionally) then in the case of periods of accretion (e.g., tidal disruption events of asteroids etc) the Earth would be flooded with gamma rays from the black hole's jet.
4. Supposing life somehow develops like on the present Earth and becomes ~space-faring, we'd have a laboratory to test and develop quantum theories of gravity, vastly accelerating scientific progress.
] |
[Question]
[
Giant dome concepts are beautiful, but I can't help but wonder how they could be so fragile. If there is even the tiniest rip, the whole thing would rapidly decompress. How would you protect against decompression?
[Answer]
# Multiple layers
Why have only one layer of dome? If you have two layers of dome, this is much more durable. Three is more durable yet.
# Internally divided cells
Airships do not have a single inflated envelope. Instead, the internal structure of a blimp is divided into a bunch of different cells. A Martian dome could, instead of being a hemisphere, be a [icosahedron](https://en.wikipedia.org/wiki/Icosahedron) with an internal structure dividing it into neat polyhedral sections. If one or more of the outer sections decompressed, the residents could still be safe in the inner sections.
# Low pressure
If you keep air pressure low, then decompression won't happen as fast. People can make it in 50% of Earth's air pressure; this happens at roughly 4000 meters altitide, where there are large cities like [El Alto](https://en.wikipedia.org/wiki/El_Alto) in Bolivia. This means the rupture does not have as much pressure on it, and failures will be gentler than they would at higher pressure. This can also decrease the time needed to make repairs: ruptures at a lower pressure differential tend to be less catastrophic.
[Answer]
**Decompression would not be rapid** in most cases.
This is assuming that you have a relatively small hole in a relatively large dome, kept at or around one atmosphere of pressure. It turns out this is a situation that people think of a lot in the context of airplane safety. (Though airplanes are a fair bit more complex, since they often encounter problems at a cruising speed of several hundred miles per hour. Windstorms on Mars can be intense but they're not *that* intense.)
Anyway, while looking into some persistent myths about air travel, the Mythbusters contacted NASA who gave them the following estimates:
* A one-foot hole in the side of a 747 will take about 100 seconds to empty it of air, provided nothing is replacing it.
* The maximum force exerted by the air leaving is about half a ton; this falls off with distance.
Plugging in my own rough estimate of the size of a 747, that's about 200 cubic meters of air per second. Which sounds like a lot, and in some respects it is, but cities are huge, and therefore it follows that dome cities have to be huge too. Let's say your primary dome is a mile across (1600 meters) and is a perfect hemisphere. Its internal volume is a hair over a *billion* cubic meters. If you poke a one-foot hole in a one-mile dome, it will take almost *two months* to drain all the air out. Needless to say, that's plenty of time to get a maintenance crew in place.
The size of the hole makes a big difference, of course. If instead of roughly 30 cm across, it's more like 30 *meters* across, you're going to lose air correspondingly faster. (In about 10 minutes, in that case.) Your engineers should take that into consideration, designing the system to mitigate and contain impacts. But it certainly isn't the case that "the tiniest rip" will lead to all the air vanishing in a matter of seconds, as is sometimes seen in fiction.
The pressure also plays into how quickly air will leave the hole, obviously. (In a sense, air pressure is how much the air "wants" to escape. In a system in equilibrium, where the pressure is the same on both sides, there's no impetus one way or the other.) 1 atm is not that much pressure, but you could go lower to limit the escape rate if you wanted to. Your municipal air cyclers might be programmed to only feed out a certain amount of air after a breach, to sustain life in certain parts of the dome while limiting the amount of perfectly good oxygen wandering off into the atmosphere.
There's also the consideration of debris. In an airplane, one of the hazards of decompression is that objects can strike the edge of the breach, tearing it wider. A half-ton of force sounds pretty intimidating, but remember that that's only near the breach itself. If the breach is high up on the dome's side, the force is highly attenuated by the time it reaches any loose objects on the ground. You should also contrast it with the weight of the dome itself: if it can withstand all of that downward force all the time, an additional upwards force is not likely to be catastrophic. (You shouldn't take that on faith, of course; your engineers should make sure the dome can handle secondary impacts relatively gracefully.)
So how would you protect against decompression? By using the size of your dome to your advantage. Construct the dome in sections or tiles, supported by a rigid frame that's capable of limiting impact damage to one or a few tiles. It's no good to have a huge glass surface that can crack in one go, no matter how unlikely that is. Your frame should take the brunt of any really big impacts, like stray meteors or crashing space elevators, leaving the tiles themselves with smaller hits.
When an impact occurs, maintenance teams will first isolate the gap using a caisson: in this case, basically a big tarp that gets epoxied in place. It doesn't have to be pretty and it doesn't have to last, it just has to keep the air in while they remove and replace the damaged tile(s). It would be good practice to keep spares on hand so you don't have to wait. However, although critical, this isn't an emergency procedure.
[Answer]
Let's say what we are afraid of is small metiors
Step 1, controlled failure
Make the points of the dome weaker than the glass. Let's say each square of glass is about 1 by 1 meter. This way when the glass is hit hard enough instead of breaking, a small section is knocked out. There are no cracks, no spreading damage. In a perfect world 1/4 of the connection could even be a hinge so the broken tile does not fall off, and may instead be sucked back closed.
Step 2, Repair cannons
Now we know that we only lost a couple of square meters of dome. We simply need cannons to fire 10x10 meter patches. These patches are desired to stick to the grid which is now exposed as we have a clean break. They also are easy to aim as all airflow guides them tot he hole. A couple of shots, and you can wait for an emergency crew that just needs to install a few standardized tiles to replace the broken ones.
The biggest problem is the 1 square meter tiles crashing to the ground. People may get hurt, but not as bad as a full depressurization of the base.
For a more massive failure, all buildings should also be emergency shelters. Once an emergency is detected. all airtight doors should enable keeping people inside safe. People outside would need to seek shelters that feature airlocks. Many locations outside should feature oxygen masks. These would allow people to keep breathing as they head to a shelter.
[Answer]
Logan's Run world had its perks, but you are right - those domes are too fragile. I want to live under a durable dome. I want to live under a
**Self healing bubble dome.**
[](https://i.stack.imgur.com/ARlhs.jpg)
<https://io9.gizmodo.com/this-self-healing-soap-bubble-is-the-best-thing-youll-s-1585163115>
>
> In a soap bubble, the soap-to-water ratio isn't homogeneous. Some
> places have a little more soap than others. Those places with mostly
> water, have a higher surface tension. The molecules pull together
> there, and as they pull together, they bring more soap molecules into
> the mix. Meanwhile, places with too much soap stretch out until the
> soap molecules are so thinly dispersed that it starts pulling together
> again. Simple as it is, a soap bubble is a self-healing, or at least
> self-stabilizing, structure
>
>
>
This bubble dome will not be a geodesic dome, or a giant fishbowl like the dome over Springfield in the Simpsons. This stately pleasure dome will be flexible, maintained with a constant infusion of the molecules which comprise it. Penetration will be met with aikido-like fluidity and regeneration.
How, you may ask, can a humble bubble contain higher pressure on the inside than on the outside? That is material for another question...
[Answer]
The risk of rapid decompression is quite low from a tine hole (tiny in comparisson to the whole structure), as others already mentioned.
One possible method would be a three layered dome: The inner and outer layer are made from transparent tiles, where each tile would crack individually if something struck it hard enough.
The middle layer is made of breakable containers filled with a liquid that resembles building foam: Expanding and then solidifying when the container is broken, and thus filling the breach.
For further security, every tile and container should be equipped with sensors so damage control knows exactly where a breach occured.
[Answer]
I want to preface my answer by stating that the "dome", per se, is volumetrically inefficient. But it is certainly more attractive to humans than what is currently planned. Also, if we're going to fill something like an O'Neill cylinder with air, why not a dome?
As has already been said, decompression probably would not be rapid. Anything that would punch a hole big enough to cause rapid decompression would also cause a lot of other damage.
I went and found a napkin on which to scribble some rough calcs, and it looks like a 1 metre hole punched through a meager dome only 1km in diameter and about 450m in height would take about two weeks to totally empty of air. I used no calculus in this answer; as the pressure slowly decreases less air will leak out per minute and it would actually take *much* longer to *totally* empty the dome of air.
A 2 metre hole would require about 3 days; an 8 metre hole would be fairly substantial but would still require 5 hours. Again, no calculus. Note that's the diameter of the hole; an 8 meter hole would have a cross-sectional area just over 50 sq. metres.
And remember that's for a 1km diameter area. That's not really such a large area as far as towns here on Earth are considered. The town of Grimsby, Ontario, has a population around 27,000 in an area roughly equivalent to a 4km circle, but it would be reasonable to assume that a planned dome community would have a much higher population density and be better organized.
It's also reasonable to consider that not all activity would take place under the dome, or possibly under a *single* dome. Perhaps there are multiple domes for different activities, such as agriculture, or for community expansion.
To get on to answering your question, I'm sure the colony will be constructed in such a way as to provide shelter in the event of any kind of pressure loss, such as air-tight domiciles or underground facilities, and that there will be a civil plan on file in the event of decompression.
As far as fragility goes, I question that assumption. You use the word "rip", but I doubt that an inflatable dome large enough to house a town-sized population would be considered. Probably something more like the traditional "glass dome" like structure often portrayed in old science fiction, or a dome-like structure with a "roof" consisting of a number of smaller dome-ish structures. Mars seems to have an abundance of silicon to support such a construction.
Whether an actual dome would actually be both feasible and viable is a different consideration, but you asked about a dome so I'm answering about a dome.
Hope this helps.
[Answer]
A colony on another planet could live in a dome structure without necessarily living in a dome like you imagine. Instead of a vast dome covering a city with separate buildings, there could be a city inside a vast dome shaped building with multiple floors and walls inside.
The building could be as wide as the Pentagon and as tall as the Empire State Building. Each of the lower floors could have as many rooms as the Pentagon, and the number of rooms would get smaller in the narrower higher floors. Various businesses and households would occupy different rooms.
And perhaps every single room in the vast building could be sealed off from other rooms. Thus if there is a leak all compartments affected by the leak could be sealed off to prevent further air losses - preferably after everyone in them was evacuated.
A spherical shape has the least amount of surface that can be pierced and lose air relative to the volume enclosed, so a semi spherical dome is a good shape for an airtight building containing an entire colony that fears having their air leak outside.
And here is another design idea for a domed colony on a world with little or no air, that is a bit more similar to your original idea.
A hole like a flat cylinder is dug in the Martian soil, deep enough to build building several stories tall in it. Buildings several stories tall that can be individually pressurized are build in it, with their roof level near the original ground level before the hole was dug. Sections of roof are built from building to building, so that the entire settlement has an airtight roof to hold atmosphere in.
Some of the excavated material from the hole is put on top of the common roof, piled several feet deep, to help insulate the settlement and to keep out dangerous radiation.
Each building should have a penthouse structure sticking up above the common roof, with airlocks, passenger and/or freight elevators, and/or stairs down to the building below.
And at the sides of the cylindrical hole there should be several long ramps gradually descending to the bottom level of the hole, for vehicles.
Outside the radius of the cylindrical hole and the ramps there should be a dome. It is good to have as much atmosphere as possible in the settlement, so that severe changes in the atmospheric composition, which would be dangerous, would be less likely. The more air there is, the harder it is to change its composition. The dome should have a wall at its bases with airlocks big enough so the vehicles can go through.
So they would fill up the dome with a thick, Earth like atmosphere, just like inside the underground community, in order to have that extra amount of atmosphere.
But the entire underground settlement can be quickly sealed up airtight if there is a leak in the dome, and will have enough air to survive for a period several times as long as the estimated time to repair the doom and fill it up with Earth like air again.
[Answer]
The same way that we do in submarines. Training. In fact my first underway involved a duct tape affrair on the shaft seal that only started running to the bilge pump at 300ft. I think a Mars colony that is leaky by nature but troubleshooting is the status quo is not only more realistic but also more interesting. Have everyone trained in damage control so that the things that seem awful that are going wrong constantly are handled nonchalantly by the locals
] |
[Question]
[
**Closed.** This question is [off-topic](/help/closed-questions). It is not currently accepting answers.
---
This question does not appear to be about **worldbuilding**, within the scope defined in the [help center](https://worldbuilding.stackexchange.com/help).
Closed 7 years ago.
[Improve this question](/posts/36669/edit)
I finally managed to make and test my Love Potion, and I'm ready to sell tiny vials at exorbitant rates. But I'm afraid someone is going to analyze it, and steal the recipe.
Is there a way to lock the formula (at least for a good long while)? Is there a method of selling it to ensure it doesn't get into the hands of scientists? **How can I keep my Potion formula to myself?**
---
**Love Potion #9**
If it's relevant, the potion is sprayed by the user like a perfume. Suddenly for the guy who people say, "eh, he's got a nice personality," all straight women and not straight men suddenly think, "wow. He's really, really hot - I can't put my finger on it." It doesn't affect other traits, and it doesn't cause people to lose control over themselves or anything like that.
[Answer]
**Don't patent it.**
*Keep it secret, keep it safe.*
Getting a patent means you release the process and chemical formula. If you want to hide it, you keep it a trade secret.
A chemical formula can be known without knowing how to make it. It's highly likely that the process you used to create the potion was not as simple as tossing some ingredients into a cauldron. It probably required very precise mixtures, which needed to be combined at very specific temperatures, pressures, and in a very particular order. That procedure is your trade secret.
On top of that, the chemical compound itself may not be easy to determine. We don't have microscopes that can simply look at the arrangement of atoms and get the formula. It's an exhaustive process of heating, mixing, titrating, etc. in order to determine what is contained in a formula. The great thing about that is it's a highly destructive process! If a company wants to figure out what's in your product they're going to need to buy a lot of it to figure it out. From there, they won't necessarily know how to actually make that formula, that's still your secret.
Also, I have no idea why, but your question is super hot.
[Answer]
>
> I finally managed to make and test my Love Potion, and I'm ready to sell tiny vials
>
>
>
Are you in US? Bad news then, I am afraid. The product falls under cosmetics (`articles intended to be [somehow applied] for ... promoting attractiveness`), which is FDA regulated. [Specifically](http://www.fda.gov/Cosmetics/GuidanceRegulation/LawsRegulations/ucm074162.htm),
>
> FDA requires a list of ingredients for cosmetics marketed on a retail basis to consumers (Title 21, Code of Federal Regulations (CFR), section 701.3)
>
>
>
So you will need to disclose the list of ingredients, and hope that the word doesn't leak.
[Answer]
From the viewpoint of a biochemist, there are a number of powerful methods that one can use to decipher the contents of this potion using standard analytical chemistry techniques.
## Mass spectrometry/chromatography
This is an extremely powerful technique, and modern mass spectrometers can be used in ways that will make it extremely difficult for non-scientists to confound them. For example, [Green's answer](https://worldbuilding.stackexchange.com/a/36678/4790) suggests that one spike it with many different chemicals. A modern analytical chemist would easily defeat this by passing the mixture through a tandem GC-MS ([gas chromatography](https://en.wikipedia.org/wiki/Gas_chromatography) mass spectrometer) which will separate out the spiked contaminants.
The gas chromatography machine will be able to separate out the various spiked-in chemicals that are interfering with the setup by the time they take to pass through the machine. By using different column coils (which bind chemicals with different affinities), chemically different compounds can be easily separated from each other. Once the unknown (new) secret ingredient is found, it can then be studied further.
Chromatography can also be used to filter out other irrelevant ingredients by fractionating the love potion into various subsets. Tools such as the [Äkta series of chromatography machines](http://proteins.gelifesciences.com/products-for-proteins/protein-purification-systems/?intcmp=GL-intbnr-IBLaunch-16Dec2015-AKTALabScale-cSpot) can be used to further narrow down the possible chemicals by testing the fractions which retain love potion activity, discarding those that do not have significant activity.
**Countermeasures**
There are a few standard assumptions that biochemists make, and violating these assumptions during the process of manufacture can completely mess up their compound libraries.
**Using isotopically unusual mixtures**.
The [natural abundance](http://www.chemguide.co.uk/analysis/masspec/mplus1.html) of carbon-13 is around 1.1%, but if you use an isotopically pure carbon-12 or 2.2% carbon-13 mixtures, your adversaries would not be able to get matches on their compound libraries, making it far more difficult for them to isolate your compound of interest.
**Conjugating your active compound to a mixture of proteins**
While mass spectrometry can measure small molecules easily, it still has [difficulties in proteomics](http://www.ncbi.nlm.nih.gov/pubmed/15540203), due to the large and varied structure of proteins. By conjugating your chemical of interest to different proteins, its MS signal will be mixed into the protein, making it far harder for ad adversary to determine the chemical you are using. It also makes it very difficult for chromatography, since the different proteins will fractionate into every fraction, preventing them from easily finding out your secret ingredient.
## NMR
NMR (nuclear magnetic resonance) allows one to determine the exact structure of a chemical once it has been purified. As a result, NMR alone is unlikely to reveal the nature of the chemical, but once the chemical is purified, it will be used to find the structure, and then allow organic chemists to synthesise your compound.
**Countermeasures**
Using isotopically pure, [NMR-insensitive nuclei](https://en.wikipedia.org/wiki/Nuclear_magnetic_resonance#Nuclear_spin_and_magnets) (such as carbon-12 and oxygen-18) will make it impossible to detect the absorbances of these nuclei. While proton NMR is still possible, the impossibility of getting NMR spectra from such chemicals will make it extremely difficult for the analytical chemists to determine the compound.
Overall, given enough time and resources, the secret will be broken by a sufficiently determined adversary. However, these techniques will force them to undertake a long period of R&D, and greatly extend the time period during which you can make money.
[Answer]
**Find the nearest mad chemist then ask them how they would go about discovering the formula of a liquid.** Take note of whatever tools and techniques they describe then incorporate countermeasures to those tools and techniques ineffective. Below are a few examples of equipment that might be used by an attacking chemist to discover the formula.
*[Mass Spectrometers](https://en.wikipedia.org/wiki/Mass_spectrometry)* - Include doping elements that will throw off the weight. Assuming that Love Potion #9 is an organic compound, spiking the formula with extra nitrogen, oxygen, carbon and hydrogen could make a mass spectrometer less helpful.
*[Roto-vap distillers](https://en.wikipedia.org/wiki/Rotary_evaporator)* - This is perhaps the hardest one. Roto-vap distillers can very precisely boil off chemicals.
*Centrifuges* - Combine other inert molecules of the same weight to prevent separation by this method.
*Common and Uncommon chemical catalysts or reactants* - This is a hand-wavey "Add in extra things that will make common organic chemistry reactants less effective in figuring out what the secret ingredients are". (I'm not an organic chemist so my knowledge is limited to knowing that there are chemical reactants used in determining the properties of an unknown substance, but I don't know what those reactants are or how to use them.)
As stated in the question, you can't prevent someone from discovering your formula, eventually. What you can do is make such a devilishly difficult chemical cocktail (while remaining non-carcinogenic, non-toxic and effective) that it will take years or decades for an "attacker" to figure out the formula. While they're figuring it out, you'll be making bank.
[Answer]
## Marketing, marketing, marketing
Real world examples:
* Coca-cola recipe? [Already known.](https://cooking.stackexchange.com/q/46296) But people keep buying Coca-Cola because marketing and brand recognition
* KFC secret chicken recipe? Again, well known. But colonel's face is what actually makes chicken "finger licking good"
* Big Mac sauce? Again, I saw so many recipes on the internet that I doubt it is still secret
**Make sure you promote your brand:** I know that it is easy to avoid marketing when you have a product which actually does what is said on the label. But if you also create a well recognised brand, you can be less scared at a time when someone cracks your formula
[Answer]
1. Add lots of very complex and irrelevant stuff.
2. Patent the hell out of anything and everything, from the potion vial design to the irrelevant stuff, including on a footnote of a subparagraph the actual stuff.
3. Hire an ARMY of lawyers and use them to sniff for the slightest hint of infringement and hound the hapless infringers into bankruptcy.
4. Don't sell in China
[Answer]
I agree with the obfuscation strategy, but the best way to do this would be to include several ingredients which are *folk aphrodisiacs*. This will cause a tremendous amount of disinformation amongst folks who say: "See! I told you that tiger testicles work!!!" Also, it makes any chemical analysis harder, because of all the potential chemical targets to analyze. This is a form of physical [steganography](https://en.wikipedia.org/wiki/Steganography).
Better yet, sell your potion as an additive to coffee, which already contains over [1000 compounds](http://www.rsc.org/chemistryworld/Issues/2011/May/ChemistryInEveryCup.asp), all natural! It will be nearly impossible to find all the non-coffee compounds. Think "Red Bull for lovers".
[Answer]
Make it biological. A tons of stuff that *lives* like cells and so on cannot (yet) be seen, scanned or whatsoever. Microscope stuff that you see is often dead and artificially-colored in order to let people actually see it. This would also have the advantage that you could have a very fast-expiring mix (when cells inside are dead, it works no more).
[Answer]
Obfuscation! You add steps in the process that are inert and don't affect the end result. You can also add in inert ingredients (though you might need to test this to make sure they don't affect the end product.
And you keep the 'secret' ingredient or process hidden.
However, mass producing this using some kind of industrial plant, will be VERY hard unless you plan to be the one to add the secret ingredient to every batch.
Though you could likely get rich keeping the production down to a level that you CAN over see every batch produced.
But ultimately, the only way to keep a secret, secret is if you are the only one who knows. But you could get a patent on it and let someone else make it for you and they will 'protect' their interests!
[Answer]
I have another idea, don't let them analyze it.
By that I mean be the one who uses the love potion on people.
You sell a service instead of the product, you are a matchmaker who make people fall in love.
The happy couple might need to come in for regular visits at their family doctor's office(who you employ to continue distributing the potion) but its a service nonetheless.
I guess at one point someone might try and get the blood of whoever has the potion in their system but I would imagine it will be much harder to figure out what the potion contains.
It might require you to abduct a few people here and there but hey, in love there are no rules...
] |
[Question]
[
A certain part of the continent is currently dealing with a plague of undeath. It takes many forms, with corpses rising from their graves, strange creatures roaming in the night, seemingly driven by some unknown malicious presence. To the humans who have the bad luck of calling these lands their home, the most dangerous strain is possibly vampirism, which some would call a curse and others a disease - both correct in essence - and which differs by the manner that this infection affects the living rather the dead.
Of course it would be easiest if the cities could just shut their gates and its people cower behind their walls (the village folk not having such an opportunity), but alas that is not possible. People must eat,and for that they need farmlands and other resources that cannot be found or produced inside the walls. Trade must happen and travellers must take the dangerous journeys between cities and villages. And as the undeath looms for years in the lands, so do the cities and people survive it.
That however brings forth the question: **How do cities protect themselves from vampirism?**
And to clarify, how to protect from vampirism - the curse/disease getting into the city, threatening to infect the people (and cause deaths through vampires that it will inevitably create). The question is NOT about how to protect the city from vampires - individuals who have contracted vampirism, **have already turned** and may or may not intend to get into the city.
**Setting**
* Tech level would be comparable to late medieval ages, no gunpowder
* Medicine slightly more advanced than late medieval, there are actually some plants and materials with magical properties, which can be used in medicine to some extent
* Magic does exist but is generally rare and has limited capabilities (in human hands). One can assume each of the cities in question will have one mage, possibly with an apprentice
* The cities will have city walls, but not the entirety of buildings can be encompassed by them.
* The cities may have sewers
* Scholars and mages are well aware of vampirism and its characteristics, the common folk are less educated and can have some misconceptions, but are aware of vampirism.
**Vampirism**
So a few more words about vampirism and vampires, so everyone know what we're dealing with.
*How can one be infected?*
The infection can be contracted in two ways. One is to be bitten, but not killed, by a vampire (typically that only happens if a vampire is forcefully removed from the victim, as a feeding vampire will have the instinct/compulsion to suck the victim dry. A person who dies during the feeding will be, well, dead and **not** turn into a vampire.
Second way of becoming infected is to be bitten by an animal that carries vampirism. While animals themselves do not become vampires, all mammals can act as hosts for vampirism and infect through bite. Being the carrier of vampirism also makes them more aggressive and more likely to bite, a bit like rabies.
Once a person is bitten there is one last resort to attempt to avoid infection - if the bite is on a limb, removing the limb might save the person if done quickly enough. And since we're dealing with slightly better than medieval-ish levels of medicine, well...
*What happens after infection takes toll?*
An infected individual enters a period which we can call incubation or which the scholars would call *penumbra*. At this stage they're still human and alive. Penumbra may last from a couple days to a few weeks, depending on the individual, with factors impacting that time not being fully known. During that time the person may experience brief episodes of photophobia, or sensory overload from their senses becoming enhanced for short while. At the same time they will gain immunity to other diseases and will gradually become less and less sensitive to pain. There is no cure, but the infection can be "stopped" - if the person in penumbra is killed, they will NOT turn into a vampire.
Penumbra ends with the process called *umbra*, which is a fancy way of saying "vampirism-induced agony". And that's exactly what it is - the person will feel a lot of pain and eventually die as their heart stops and a few minutes later they will reawaken as a vampire. It is important to note that once a person enters umbra, there is no way to stop the turning, even if they are killed by some other measures, they will still rise as a vampire.
*Vampirism Stage I*
And so we have our vampire. For the purposes of this question all I consider important is the following (ask in comments if something is important that I didnt think to list):
* The vampire retains their memories, intelligence and personality they
had in life.
* The vampire must feed on human blood. It is necessary for surival, but is also an addiction. As the vampire drinks when not thirsty, the vampirism will progress, further twisting their mind and
body.
* The vampire in the first stage exhibits following external
traits: pale skin, red eyes, fangs. They also do not have a heartbeat and they only need to breathe in order to speak. As it progresses they will become
increasingly deformed and inhuman (with final stages of vampirism
leading to becoming a feral beast of the night)
* The vampire has improved senses, strength and endurance. Later on,
they can also gain limited magical capabilities - these typically only work at night and are mostly magic that is useful in combat. Some other examples include creating illusions or control over undead.In any case, these abilities will not be present in newly turned vampire so are less of a concern when it comes to that.
* The vampire is immortal and their wounds will regenerate. It is
only vulnerable to magic, certain enchanted items and wraithwood
(understandably valuable material in these parts). They are also
somewhat vulnerable to silver, as it will cause pain and wounds
that are hard or impossible to regenerate, but will not kill them
outright. While suffering from photophobia, vampires can still
walk in daylight during the early stages of vampirism, it is only
as it progresses that sunlight becomes deadly to them.
**Considerations**
There are a couple things to consider when coming up with answer to this question. In my mind the most likely ways of infection getting into the city is either by an infected traveler - be it a member of trading caravan or a villager looking to sell their products - or animals which carry the disease, such as rats or bats. While thinking of using cats to get rid of rats I realized that cats themselves are vulnerable to being bit and spreading infection, so I thought that perhaps snakes can be kept as pets instead for pest control (being reptiles and not mammals, they cannot be hosts to vampirism).
Anyway, with all that, let me reiterate the question: **What measures can be taken by the cities to prevent or at least significantly reduce the risk of vampirism getting into the city and protect the population?**
In response to comments:
How long can a vampire feed before starving?
Well strictly the answer to that would be about 2-3 weeks when talking strictly about starvation. The thirst, however, will become very hard to ignore as soon as one week has passed, driving the vampire to feed.
And of course the temptation of drinking blood, that never really goes away, even if the vampire isnt thirsty in the moment.
[Answer]
* Surround the city with walls and moat, close the gates at night, while keeping a watch on them during the day. This strongly reduces the chances that someone might sneak into the city unnoticed.
* For whoever is a foreigner or is returning from having been outside for more than 1 day, quarantine is mandatory. During the quarantine, they will be tested with light and silver, to ascertain if they are infected or not.
* Same testing is applied to the resident population: whenever the sun shines, participating in a public gathering in the sunny square is mandatory, and so is being checked with silver every week (or day). Who fails to show up for the gathering or doesn't pass the silver test is placed in quarantine.
* The quarantined who show clear symptoms are executed.
[Answer]
**Vampire Corps!**
/The vampire retains their memories, intelligence and personality they had in life./
Some vampires were bad people in life. Many were good people or ordinary people. To protect their families and help their city, such as these will form your vampire corps. They will track down and capture rogue vampires and infected animals. Bad vampires will be imprisoned until they are vulnerable to sunlight and then so dispatched. Members of the vampire corps who lose their humanity and begin the slide into degenerate monsters willingly submit to the same fate (sad music plays)
The vampire corps is also useful against other forms of the undead some of which rival the vampires in power. Most importantly the vampires of the corps might have insight into the /unknown malicious presence/ behind the plague of the undead, which true to anime form will turn out to be a lich king or ancient god that is then fought by the heroic vampire corps. To defeat the lich king, one of the corps must become the lich king and then submit to being imprisoned (sad music plays).
The vampire corps persists. With one of their own now the lich king, they no longer degenerate into monsters and stay as they are. Which is good because the corps has work to do. The anime only covers the first 7 books of the manga, and there are 33 more.
In book 27 they bust the lich king back out, because they need his help.
---
I did not mention the vampire twins! You have to have some kid characters in an anime. These are vampire kids and in charge of rounding up the infected cats and dogs. They were told to kill them but it turns out they are catching them and keeping them in a pound instead of killing them. They do get bit but they are vampires and it doesn't hurt. The infected animals eventually figure it out and come to love the kids. They infected animals come in handy. The kids say the animals are going to be cured when they find the cure.
Man this just writes itself! Or maybe it has already been written? Did I see this somewhere?
[Answer]
## **Religion!**
Vampirism is not only deadly but an ungodly disease. Anyone who dies while infected by it is going straight to Hell, no matter how many indulgences they've bought.
The only way to save yourself from Damnation is through the Sacrament of the Cleansing. You can save your soul if you turn yourself in while still within the "Penumbra". A priest will perform a ceremony, at the end of which you'll die - but you were dying anyway. However, your are now put back into a state of grace and you may ascend to Heaven.
As an added bonus, during this ceremony, other sins you may have committed can also be forgiven.
For this to work it must be made clear to the public:
* Someone bitten by a vampire is dying. They are not just turning into a supernatural immortal being. The creature that emerges is not the person, it's just a demon or some other unholy being having taken their body.
* The sacrament might not work if they willingly allow themselves to be bitten.
* You could add a bit of propaganda that vampires prefer the blood of their host's friends and family. This might encourage people to turn themselves in to protect their kin.
[Answer]
**Curfew**
People only travel and work during daylight hours and return to secure homes at night and lock themselves in. Traders have secure wagons they sleep in at night or they have rest stops close enough apart to make it there safely before night. If possible, traders use boat/ships and park well offshore where possible at night.
**Quarantine**
If someone starts showing the signs, they're locked up until certain and then executed and the body burnt. Personally I'd suspect they'd lock them in a silvered cage somewhere sunny and just wait.
**Animals**
This is the real problem. Rats are pretty unstoppable. We've been trying to kill them for thousands of years. They can swim, climb, hide, dig, crawl through tiny gaps and chew holes in walls. If rats can spread the disease, they're all screwed. There is nowhere safe. A farmer can't even harvest his crop during the day if the rats in his field are infected.
**Vulnerabilities**
You should add fire and garlic to their vulnerabilities if you want people to survive against immortals. Magic and silver is too rare for a farmer to keep himself and his family safe.
[Answer]
# Put a bounty on all animals that can be infected.
Animals are a huge danger, and you can't really risk any of them being close to you. Have bounties on them and kill every one you can.
The one exception is animals you put a silver collar on. This will cause pain to vampiric animals, and so allows you to be fairly sure who is a vampire and who is not.
# Test all travelers.
Any traveling group will need to be tested before entering a city. This can be done by having them touch silver, holding blood in front of their face, and checking their heartbeat.
They would also be expected to regularly check themselves.
# Build steam engines and powerful fire weapons using corpses.
While you can't kill them, you can use them as sources of fire. Stick them in engines and use their burning corpses to power tools and useful items. They regenerate, so you have an effectively endless source of fire and energy for all purposes. This should help with the excess vampire animals.
[Answer]
# Magical biological filter
Vampirism is clearly a disease spread by some microbiological agent. It has very similar spread and development to the rabies virus. Without loss of generality, let's assume it's a virus. Now all you need to do is cast a filter for that virus on the city walls.
**Step 1: Isolate the vampirism virus.** Get tissue samples from several people in the penumbra stage and several normal humans (the virus doesn't necessarily travel through the blood; [rabies moves through nerves](https://www.cdc.gov/rabies/transmission/body.html)). Use a magical comparison spell to identify the things in the proto-vampire tissue that is not in normal human tissue. This is going to take a lot of trials to get right, especially without knowledge of microbiology. Layered enhanced vision spells can substitute for a microscope.
**Step 2: Create a filter spell for the vampirism virus.** This should be easy once you've isolated a pure sample of the virus, but you may need to do this as a fairly rapid follow-on to a successful isolation because I assume that the virus would degrade rapidly in open air (since it does not appear to have airborne spread). To aid in this, the isolation process should probably be combined with a time slow spell or a time stop spell to prevent the degradation of the isolated virus for long enough to craft the filter spell.
**Step 3: Cast the filter spell on the boundary of the city.** This will require the city to have a continuous boundary. This is easy to do on walled cities or cities that use a combination of walls and rivers. For other cities, or for cities with gaps, you need to make a [nominal perimeter](https://en.wikipedia.org/wiki/Eruv) to hold the spell and inspect the perimeter regularly for integrity. A continuous fence with gates should be sufficient and within the technological means, so long as each gate has a top piece (preventing the perimeter from "breaking" every time the gate is opened).
Following this, any vampire that tries to enter the city will have the virus ripped out of them. This would likely be excruciatingly painful and almost certainly fatal, but the most important detail is that they would not be able to infect anyone following this process. Additionally, infected animals will be cleansed upon crossing the barrier. This is likely the origin of the myth that
vampires can't cross running water; it's because of the number of vampirism virus filter spells that were cast on the rivers around major cities.
This has the added benefit of allowing infected country-folk in the penumbra stage to visit a protected city and get cured without needing individual attention from the city's mage. It will likely be very painful, as virus is ripped from their body, but also likely not fatal, as at this point they are still alive by their own biology. This keeps the city from starving due to it's surrounding farmers all becoming vampires. So long as the farmers make a trip to the city once a week, they should be fine. Wagons with the filter spell could also be made and enterprising folk could take them on tours of rural villages and charge a fee for people to get their weekly vampire cleanse.
There is an added logistical problem if this can affect **any mammal**, namely infected livestock. For this, you'd need to find some way to produce filter spells in larger quantities. At a minimum, every farmer would need to install a new barn door frame enchanted with the vampire filter. As long as you're doing this, you might as well sell personal door frames with this too, thus allowing richer folk to remain protected. This also explains where the myth that vampires can't cross a threshold comes from; if enough houses had door frames enchanted with the vamprism virus filter, that would certainly start to spread as a rumor. Note that under this construction, the vampire being "invited in" wouldn't suddenly grant them the ability to cross the threshold.
## Non-magical solutions won't work
You've made spread by animals overpowered. We can't even manage to keep rats out of cities in the modern era, and the medieval era was even worse. If rats can spread it, cats (the top medieval rat defense) can spread it, and livestock can spread it, you get the [Black Death](https://en.wikipedia.org/wiki/Black_Death) times 3, namely total destruction of the population.
[Answer]
You're going with supernatural vampires, but were vague on details. The oldest myths are also vague on details, as it turns out.
Whatever those happen to be, a medieval town is ill-equipped to deal with. They lack most of the modern insights we have into city management and disaster management. Their ideas about quarantine are primitive or even non-existent. The population will be even more prone to panic (they have never heard of a city that was able to deal with disasters, unlike you and I), and you will have petty feuds boiling over into accusations of either being vampires or harboring them.
Supposing that the individuals in this city have some idea how to go about the business of either killing or excluding vampires, and assuming this knowledge is widespread, then a singular leader with enough power and the resolve to see the city through this ongoing crisis is absolutely necessary. When others start to panic or misbehave, he will put a stop to it immediately and, I think, not so gently.
However poor their protocols are at first, they should see some success, and having survived long enough might yet survive longer and refine those.
But be not fooled, this is very much a problem of city/disaster management, and not a problem of sparkly bloodsuckers and their disdain for those who can still safely sunbathe.
[Answer]
**Surrender.**
Offer a powerful vampire, or faction of vampires, lordship of the city. Strike a deal with them whereby the cityfolk will volunteer their blood for the vampires' consumption, in exchange the vampires agree to limit the number of people they will kill, perhaps only condemned criminals are open game for vampires, or human citizens have to submit to a lottery, where the unlucky winners are sacrificed to the vampires.
If the vampires retain their human intelligence, they should recognise that this arrangement would be mutually beneficial. The human cityfolk gain stability, and the vampires get a regular supply of blood, without having to worry about overexploiting the supply and wiping the city population out.
[Answer]
Mandatory daily public nude inspections of everyone at noon. The threat will overcome any nudity taboos that might have existed. Anyone photosensitive is immediately killed.
[Answer]
# Garlic
If the vampires are repulsed by garlic, force everyone entering to submit to eating a piece of garlic bread for admittance
# UV Light
If your mage can create something akin to sunlight, the gates (and possibly the tops of the walls) can be protected by them
# Religion
Carve crosses at all the entrances, assume they work against your particular variety of vampires
# Silver
Some types of vampires (and werewolves) are burned by silver, so along with the garlic bread, you can have them touch metal to gain admittance
# Tame Vampires
A crew of vampires can help the city guard detect other vampires... if they can be trusted
] |
[Question]
[
## Harvesting explosions by containing them in a time bubble.
Here's an interesting sci-fi concept, which involves generating a time bubble in order to slow a nuclear explosion to the point where the energy that leaks out of the bubble can be safely harvested. Over a sufficiently long period of time 100% of the explosion would be converted to electrical energy. A spherical chamber could encircle the time bubble to collect light, heat and radiation emitted by the explosion. In a certain way, this is a scaled down version of a Dyson sphere or a fusion reactor but we'll get to that later.
The time dilation would turn the light into infrared, which can be harvested using thermal energy conversion. Same system as nuclear reactors. BUT! I plan on using an H-bomb (hydrogen bomb), which fuses hydrogen into helium upon detonation, giving us extra energy compared to an ordinary atomic bomb. Like a nuclear/fusion reactor. All this energy being released instantly means I'll need to know how much time would need to be dilated to not overheat and destroy the thermal power plant surrounding the explosion.
## By how much should time be slowed for this to be safe and efficient?
[Answer]
**Step 1: Handwave away all those pesky things that science tells us**
There are not very many ways in which one can even theoretically cause a significant amount of time-dilation, and those that do exist involve costs that would make your time reactor unbelievably more expensive to build and operate that you could get out of it... that said, many authors introduce cheap time dilation that they can just blame it on some unique property of Unobtanium or Clarke Tech and move on. The other thing to handwave away is 100% efficiency. 70-90% efficiency is far more realistic; so, to account for this you will either need to adjust your final figures or again go the Clarke Tech route for collecting all that energy.
**Step 2: Pick your nuke.**
The smallest hydrogen bomb ever tested is North Koria's 30kt hydrogen bomb. It is widely believed that this test was actually faked, making the smallest confirmed H-bomb the 100kt W76 warhead, but either way, you don't want to go with the smallest H-bomb if you have cheap time-dilation. You want to go with the biggest possible H-bomb. The reason for this is that the most expensive part of an H-bomb is actually the fission bomb that you use to get it started. So, assuming you get a positive energy return at all out of this invention, it means you get more bang for you buck going with a bigger bomb. So instead we will want to pick something more like the 50,000kt Tsar bomb which translates to a power output of about 210,000,000,000 MJ
**Step 3: Pick your power output.**
Since this is basically a nuclear reactor, you should look at the power output of a single reactor in a nuclear power plant. You should not be looking at the output of non-thermal reactors, or total output of a multi-reactor plant since this is going to be a single thermal reactor per bomb. The highest output per individual thermal reactor in the world are about about 1300 MW each. So to convert a Tzar Bomb's blast into an output of just 1300 MW, you would need time to slow down to an average of about 1/160000000th normal time giving you an explosion that would last for just a bit over 5 years. Note that I say average for a reason since, as Dan's answer points out, it will not be a uniform flow of energy you need to slow down.
[Answer]
It's not that simple.
A nuclear explosion is not a simple thing. It comes in phases. Those phases are, of course, separated by very small amounts of time.
One phase is the release of gamma rays. You can see the effect of this in the so-called ["rope trick."](https://en.wikipedia.org/wiki/Rope_trick_effect) The image is from the Tumbler-Snapper test, one of the above ground tests in Nevada. It shows the cables holding the shot cab being heated to vaporization temperature ahead of the shock wave of the blast.
(Note: Thank you to Vikki for pointing out I had mis-identified the source of the image.)
[](https://i.stack.imgur.com/NLibE.jpg)
The gammas come out in the first few micro-seconds. The shock wave requires milli-seconds to get as far as it has in the image. So the cables had time to begin their own little explosions before the main explosion shock front got there. You can even see the ground under the explosion begining to glow due to heating.
The doubling time of the rate of energy release in the explosion is something on the order of 1 microsecond. It depends on the design. The gammas will carry some few percent of the total energy of the explosion. And they will come out at the speed of light, nearly $3\times10^8$ m/s. So you get this pulse of gammas with a few percent of the energy coming out within a few micro-seconds.
So you will need to slow that part of the explosion by a huge factor or you will get nicely fried if you are anywhere near the explosion. If it was a 1 MT explosion, then probably 20 kT worth is in the gamma pulse. And you need to spread that roughly 5 microsecond pulse out to long enough that it does not fry you.
The next thing to come out will be the neutrons. They come out over many milli-seconds. This is because they come out with a wide range of energy, so a wide range of speed. The high end ones are doing about 10 MeV, say something like 0.005 the speed of light. The slowest can be arbitrarily slow. This will be followed by a soup of other radiation, alphas, betas, protons, etc. This pulse will also be some few percent of the total energy. And will come out in a liesurely few milliseconds. And will continue to be released at diminishing rates anywhere there are fission fragments.
Following will come the fission fragments, and the heated up non-reacting components of the bomb. These will be coming at speeds round about a few 100 km/s. This last relatively slower pulse contains something over 90% of the total energy.
So your tuning of the time-slower device needs to be extremely fine, and have at least three settings. Otherwise you wind up either getting totally cooked by one of the pulses, or waiting months for the useful energy.
[Answer]
>
> Over a sufficiently long period of time 100% of the explosion would be converted to electrical energy
>
>
>
About 5% of the energy will be lost as neutrinos. There's no realistic way to recapture this energy... doing so might even be *less* realistic than magical time-bubble reactors.
You're using a thermal power plant, and that means you're limited by the efficiency of the [Carnot cycle](https://en.wikipedia.org/wiki/Carnot_cycle#The_Carnot_cycle): the theoretical maximum possible efficiency is $\eta = 1 - {T\_C \over T\_H}$ where $T\_C$ is the temperature of the heat sink, and $T\_H$ is the temperature of the heat source. If the temperature of the hot end was 1000K and the cold end was ambient, you get about 72% efficiency. If you can run your heat engine at 3000K (and no, you probably can't) you reach over 90% theoretical maximum efficiency, and much above that you'll find that everything starts melting.
Anyway, you can't reclaim 100% of that energy.
Here's the real problem though:
>
> The time dilation would turn the light into infrared
>
>
>
A gamma ray photon emitted from a nuclear reaction has a lot of energy. An infrared photon does not. Where's that energy gone? Well, energy isn't necessarily conserved under general relativity, but *momentum* certainly appears to be, and photons have momentum too. So where'd it go?
Either:
1. All the gamma ray photons get redshifted into more tractable wavelengths, but the energy and momentum associated with them has poofed away into the ether. This results in a colossal loss of energy... those 1 MeV gamma photons have now become 1 eV near-IR photons, so that's a millionfold loss.
2. The gamma ray photons are *still* gamma ray photons when they leave the stasis field... maybe the *power* of the system is lower than a nuclear bomb because the deadly radiation is trickling out over a longer timescale, but the stuff shooting out of the system is definitely not infrared
3. The interior of the stasis bubble is *optically thick*, such that you can reasonably expect all short wavelength light from the nuclear reactions to be absorbed by whatever is in the bubble, and as the resulting plasma cools and recombines it emits nice tractable black-body radiation
If you want to extract useful amounts of energy from your bomb, it can't be (1). No redshifting for you.
(3) is also awkward, because the interior of the bubble needs to be large enough to allow the fireball to develop and expand without breaching the walls of the bubble, because due to the no-redshift thing you'll end up with *an actual nuclear fireball* impinging on your heat engine, and that sort of thing is what engineers usually refer to as A Bad Thing. How big it would have to be I don't know, but you're going to want it to be at [least a couple of hundred metres across](https://atomicarchive.com/science/effects/fireball.html).
So what you've ended up with is not a magical nuke-driven heat lamp, but instead a giant incandescent radioactive fireball, which you've hopefully slowed down enough to capture all the heat and light from without accidentally nuking yourself. Unlike a regular nuclear reactor, the fallout won't be nicely contained in fuel rods either... lots of free gas and dust instead. Fun to confine and clean up.
I don't want to think about the problem of the bubble of hot, high-pressure gas wanting to rise up... maybe you can fix this by having a tile-dilation bubble shaped like an egg standing on its pointier end, but suddenly your reactor chamber is hundreds of metres across and a kilometre high and you have to wonder whether old fashioned fission reactors were really that bad after all.
Maybe it is easier just to have a merely *large* chamber, lined with something highly refractory (like tungsten) that should be able to catch and thermalize the short-wavelength photons and high-speed particle radiation without melting itself. Then you just have the problem of cooling it fast enough that the interior layer doesn't vaporize, because repairs will be awkward.
---
Now it is just a question of how effectively you can cool your blast chamber. Due to Carnot efficiencies, the quoted power of real world thermal plans is actually a lot lower than the actual amount of heat coming out of the source. The world's biggest nuclear plants today are hitting about 8GW of electric output, so they can presumably soak up more like 11-12GW of heat.
Releasing 2.5-3 tonnes-of-tnt-equivalent worth of energy over a second generates about that much power. A Tsar Bomba at its maximum yield of 100 megatonnes would run such a plant for a little under 404 days, though you might find the multi-kilometre-wide fireball a bit awkward for option (3).
If your heat-extraction capacity is lower, your time-dilator needs to be better, or you get nuked. If your time-dilator isn't free to operate, you're going to face diminishing returns as the size of the power plants decrease... your system seems like it might scale up, but it won't do a good job of scaling down.
[Answer]
**This is a great sci-fi idea because almost any solution for getting electricity would be better - but few would be cooler**
Having said that, this question falls into my "how many angels can dance on the head of a pin?" rule. Answer: "as many as wanting." You're seeking (I assume) a factual answer to a fictional scenario. One doesn't exist without making whomping assumptions. To wit:
* I'm using solar panels using today's reasonable-best efficiency standard of converting 20% of light to electricity for 2kwh per-panel in a 10-hour daylight period, suggesting I could get 4.8 kwh if the panel were exposed to continuous light and each panel is one square meter in size.
* I'm going to assume that 100% of the energy released by the nuclear blast is photonic in the light spectrum acceptable to the solar panel. Note: This is an assumption so wild, so insane, so incredibly wrong that it caused angels to weep. But it really simplifies the analysis.
* I'm going to wrap my panel around the explosion in all three dimensions and assume no equipment gets in the way. This is also a cause-angels-to-weep assumption. In reality (hah) you would *at least* have the equipment generating the time dilation field that the panel could not cover. Energy from the explosion that penetrates the field in the direction of this equipment is lost (and could damage the equipment), but like I said, we're ignoring all that.
* The total solar panel inner surface is 1.4706 square meters. This will make more sense later. It has a lot to do with me being lazy.
* I'm going to assume that I'm going to slow down the bomb's detonation to ensure that no more energy impacts the solar panel than would sunlight.
* We want energy for a long time, so we're going to detonate the [Tsar Bomba](https://en.wikipedia.org/wiki/Tsar_Bomba) — about 225 peta-joules.
* I'm ignoring entirely the fact that, insofar as we understand it, as one increases the need to slow down time, one also increases the energy required to do it.1 In other words, this can't work based on our understanding of time and physics. ***But it's your world.*** Throw us all the proverbial vulgar hand gesture and do it anyway.
All those wild-and-crazy assumptions make the calculation fairly straightforward.
One watt = 1 joule per second. And [from here](https://www.quora.com/How-long-does-a-nuclear-explosion-take) we learn that an explosion requires give-or take .0000008 seconds. If you read that response on Quora, it'll point out that this is a fairly arbitrary statement as the actual number will depend on a boat-load of variables that we're completely ignoring.
So, I'm looking to get (for completely arbitrary purposes that have to do with me being lazy), 48 kwh (10x4.8kwh) over a 24-hour period. [From here](https://justenergy.com/blog/kilowatts-and-calculations/) we learn that watts = (kWh × 1,000) ÷ hrs. So, 48 \* 1000 / 24 = 2000 watts. Watts are joules-per-second, so to get 200 watts we need to accommodate efficiency (20%) getting us to needing 5,000 joules to impact the surface of the panel every second.
Now, [NASA says](https://earthobservatory.nasa.gov/features/EnergyBalance/page2.php) Earth gets 1,360 watts/square meter from the Sun (now you know why the inner surface of the solar panel 1.4706 square meters. 10X(200/1360)=1.4706).
So, all that's left is slowing down the detonation. This is going to be so unrealistic that's it's a good thing the idea is uber cool.
Basic scalar math:
$$\frac{225 Pj}{.0000008 S} = \frac{5000 j}{X}$$
Which, when you do all the acrobatics tells you that you need the following time dilation ratio:
***1:56.25x1018***
That's not a little slow-down. That's a lotta slow-down. If you're a fan of metric prefixes, that's almost2 0.2 zepto-seconds of explosion for every second of unadjusted time. The ratio gets better as you increase the efficiency, capability, and surface area of the solar panels... but not by what I'd consider a practical amount.
And remember all those weeping angels. We made some outrageous assumptions to get to a number that you don't really need because are you really going to start playing around with the size, type, quality, and efficiency of the nuclear device, the size, type, quality, and efficiency of the solar panels (aka energy converters or accumulators), the distance between them, the size, placement, and occlusion of your time dilation generator, etc., etc., etc. This is why many scifi authors don't explain the gory details. There's always [some group of geeks](https://en.wikipedia.org/wiki/Ringworld#Errors) who will check every number just to see if you really know your science or not.
Just tell your readers that a time dilation field is used to slow the detonation of a nuclear bomb so that accumulators can convert the detonation energy to electricity. If Star Trek can make gobs of money powering Romulan warbirds with a contained "quantum singularity" (aka, a small black hole), then you're good to go!
---
1 *A fun-to-watch explanation for this comes from Doctor Who's "The Pirate Planet" where the Doctor explains why the time dams keeping Xanxia's body alive can't work. Tom Baker. Doctor Who. What more do you need?*
2 *As if the minor rounding error would matter here.*
[Answer]
There is a similar real-world plan that I have read years ago, so the idea is more or less viable:
1. Make an underground nuclear explosion, deep enough to be contained.
2. Use the trapped heat underground heat just like a natural geothermal source.
Rinse (not really), repeat, fix the thermal wells when needed.
[Answer]
1 "kiloton" is 1.16 gigawatt-hours.
As nuclear power stations designs were refined into the 1970s, economics favored a fairly narrow range of sizes - most newer plants are 1.0 to 1.5 gigawatts. So if we claim "the average semi-modern nuclear power station is 1.16 gigawatts", we're pretty darn close.
**1 *hour* of their runtime is thus 1.16 gigawatt-*hours*. Or 1 kiloton**.
"That was easy"
A 22 kiloton nuke = 22 hours of run-time of our "average" nuclear reactor.
A megaton nuke = 1000 hours of run-time.
[Answer]
# A lot, but there can be no net energy gain in this scenario
As others have said, 100% energy capture is not physically possible with real physics. I'll skip the Carnot efficiency calculation as you're not asking for it and someone already provided it. No process gives 100% useful work. That's the easy part.
Next is the calculation of time dilation. That isn't particularly hard but to reach an actual number you have to know certain parameters going in. So I will give the formula then go through the work for you.
To safely extract energy from an H-bomb by time dilation, a time dilated second s$\_1$ passes inside your time bubble in a number of *real* seconds according to the formula:
$$ s\_1 = \frac{\textbf{H}\_0}{\textbf{H}\_U \textbf{H}\_F(1-\textbf{M}\_S)}s $$
Where:
* S$\_1$ is the number of real-world seconds will pass every time one second passes inside the time bubble
* $\textbf{H}\_0$ is the power density of the H-bomb at the surface of the time bubble
* $\textbf{H}\_F$ is the power density that will cause your weakest part of the energy harvesting device to fail
* $\textbf{H}\_U$ is the power density that will will be converted into useful work by your harvesting device (based on the device efficiency)
* $\textbf{M}\_S$ is your design safety margin, or, the percentage of "slop" you want to allow your design so it will not fail
For reasons explained below your $\textbf{H}\_0$ power density will have many components, but ultimately every form of energy coming from the detonation can be converted into Watts/m$^2$ and plugged into this formula. This is the number you need to find based on the yield of your bomb and the diameter of the sphere.
For the safety margin, assume you have some coupling in the collector that will be destroyed with exposure to 100,000W/m$^2$ over 5 seconds. If you want a 5% safety margin, the max power density you can allow to "safely" (per the question) operate this device would be 5kW/m$^2$. You would dilate time enough to make s$\_1$ long enough that power doesn't exceed this number.
In the end, unless you are dilating time for free, you will not pull a net energy from this device, however you will make energy useful where it normally is not. Now the calculation:
You will be taking normally destructive energy and making it useful, but at a very low efficiency. Note also, that a thermonuclear device is an uncontrolled chain reaction with more energy yield as it grows larger. Someone calculated you will need a 200m diameter sphere, but the problem isn't really asking for a fixed yield so I will only touch on the *why* of this argument. If you bottle the bomb up into a small bubble, you will have an exponentially smaller yield compared to the uncontrolled bomb in open air. No matter, you didn't want max yield.
Disregard the thermonuclear bomb for now and just say you have a radiating body of any kind. In your case, it radiates electromagnetic waves, gamma rays, neutrons, protons, neutrinos, etc., etc. You have also introduced the novel physics that time dilation alters the wavelength of light when it is measured outside the bubble in normal time. This should not happen in your case of special relativity (we are talking about time dilation, after all) because it violates laws of conservation. An infrared photon has less energy than a red photon, for example. Where did the extra energy go?
Your question is very simple and the qualifier "safely" means we only need to find the most likely item to fail, and assume the machine fails as a whole soon afterward. That would be the safety margin. If I make this radiation come out of the bubble more slowly, smaller doses of the radiation will reach the parts of your machine per second of real-time. So you simply need to determine how many Watts per second will destroy your energy harvesting machinery. The destructive elements are many, but the calculation is very simple, and can only be given a number after knowing what your harvesting machine can withstand:
## Electricity
If you have copper wiring anywhere, for example, you need to keep the temperature *at least* below the melting point of 1,984°F, but preferably much lower than that if you want your wires to be efficient at conducting electricity. You can have better conductors with gold or platinum, but you will also need to keep the temperature lower. You will heat up any copper parts from 25° to 1,984° ($\Delta T=1,959$°) by exposing it to your radiation. This reduces the efficiency of the electrical conductor. But how much can it take? That answer depends completely on a review of your engineering design.
## Thermal radiation
We have to assume you want to harvest energy rather than destroy it. A particle leaving the blast will be moving through time more slowly but have the same energy. All you have done is change the definition of a second within that bubble. When the hydrogen's proton (or any particle) that has enough energy to undergo fusion reaches the perimeter of the bubble, unless you have caused the energy to leave the universe magically, it is still in the particle. The particle's momentum is conserved. So the proton will be traveling at the same speed as it did if time were never affected. What will change is the number of these protons reaching the perimeter per normal second. So this reduces to a simple calculation of what dosage of proton radiation will destroy your machine. As stated, the design of the machine completely determines that number. We will treat the weakest part of your machine as a black body which is absorbing heat energy (we won't use a gray body calculation because anything transmitted or reflected eventually ends up in your machine somewhere else). You need to have some heat removal method to offset the heat transfer going in.
The radiation energy per unit time from a black body is proportional to the fourth power of the absolute temperature and can be expressed with Stefan-Boltzmann Law as:
$$q=\sigma T^4A$$
where:
* q = heat transfer per unit time (W)
* σ = The Stefan-Boltzmann Constant = $5.6703e-10^{-8} \text{(W/m}^2 \text K^4$)
* T = absolute temperature in kelvin (K)
* A = area of the emitting body (m$^2$)
Now, conveniently, you are asking about a thermonuclear reaction. The sun is doing exactly what you are asking for here, and so is any fusion reactor. So let's look at the sun as an example to gauge how much energy is radiated in real time. From that, you can slow down time enough that the the heat transfer $q$ will not destroy your most delicate component.
Use a surface temperature of the sun at 5800 K, and assume that the sun can be regarded as a black body. The radiation energy per unit area can be expressed by modifying (1) to
q / A = σ T$^4$
= $(5.6703e-10^{-8}) W/m^2K^4) (5800 K)^4$
= $6.42e-10^7$ (W/m$^2$)
As you can see, the absolute temperature of your thermonuclear device—at the perimeter of the time bubble—must be known before any meaningful numbers can be drawn. That of course is determined by the diameter of your bubble, and the yield of the radiation source being considered. That can be the subject of another question, perhaps. No matter, since Watts are a unit measured against time, you are simply turning the second into a variable in this formula. You need to modify the value of the second so that the black body radiation finally coming out does not destroy your weakest link.
Let's say you have a little fancy active cooling. Now, let's say you have some thermoelectric device harvesting energy, and that device is destroyed (or becomes useless) above 1000K. That's pretty hot, but say you've designed this. Let's also say you have a small-ish time bubble and the radiation reaching the perimeter is "normally" at 5,800K, just like the sun. All you need to do is change the value of s in the Stefan-Boltzmann Law such that you are not putting more heat in than the device can dissipate.
Let's assume you can naturally dissipate heat by cooling fans at the rate of 10kW per second per meter$^2$. How long does a time-dilated second need to be to allow your cooling system to prevent overheating?
Solve the solution above ($6.42e-10^7$ (W/m$^2$)) for s by rewriting it:
* Recall: 1 Watt - 1J/s, $\therefore$ 1 s = 1J/W
$$
6.42e-10^7 W/m^2 \\
= 6.42e-10^7 \frac{J}{s m^2} \\
\therefore s= \frac{1J}{6.42e-10^7 m^2}
$$
But you need to know what the slowed second is ($s\_1$) that will just introduce enough heat to destroy your weakest component, at $10 \frac{kW}{s m^2}$. So we rewrite the above solution for $s\_1$ as follows:
$$
s\_1= \frac{1J}{1e-10^4 m^2}
$$
now we have an exact ratio for time dilation by dividing the unknown second by the normal one, $\frac{s\_1}{s}$ as follows:
$$ \frac{s\_1}{s}=\frac{\frac{1J}{1e-10^4 m^2}}{\frac{1J}{6.42e-10^7 m^2}} \\
s\_1= \frac{6.42e-10^7}{1e-10^4}s \\
S\_1 = 6,420s
$$
# A:
Given these conditions for harvesting a thermonuclear detonation which has the same energy as the surface of the sun, **you will need to slow time such that one second equals $1.78\overline3$ hours, or slow time by 642,000%**
I made many assumptions but in simplest terms, design your energy collection device first, learn where its weakest link is, treat the time bubble as a black body radiator of a certain surface area, then modify the Stefan-Boltzmann equation to solve for your new value of a second.
[Answer]
The Hiroshima bomb had a yield of [approximately 15kt](https://www.warbirdforum.com/hiroshim.htm). This is roughly equivalent to [62759999999991.5 joules](https://www.unitsconverters.com/en/Kiloton-To-Joule/Unittounit-3486-3452?MeasurementId=15&From=3486&To=3452) (let's say 62.76 \* 10^12).
The Three Gorges dam, the largest power station in the world at this writing, has [about 22.5MW](https://en.wikipedia.org/wiki/List_of_largest_power_stations) of capacity.
So, the energy from one Hiroshima-sized (15kt) explosion would provide 22MW for [2.8 \* 10^6 seconds](https://www.rapidtables.com/calc/electric/Joule_to_Watt_Calculator.html). This is just a little over a month.
If you don't need Three Gorges capacity, you can stretch it for proportionately longer. For all I know, though, you'll need at least that much to keep the time bubble running!
] |
[Question]
[
Idk if here is the right place to put it so if there is a better place, pls do lmk.
In Fantasy, lots of the stories have some poor person pretending to be a rich person or some rich person pretending to be a poor person. Usually for long periods of time, ie they are undercover or something. If there is any "plot" around it, it normally is very superficial i.e. poor person says "I was poor and I never had all these forks and stuff, which one will I use?" or rich person says "I was rich and I didn't know how poor these poor people are" and then it is completely brushed over.
I was thinking, in our real world (lots of fantasy is set in a medieval like world but let us focus on our present day since we won't have to be historians as well), how hard would it be for an individual to pretend to be in a class in which they are not.
I was thinking that in our modern time period, accents would be a huge thing which would be hard to fake for a long period of time. I am an American but I know what the "pop culture" rich British person's accent sounds like and what the "pop culture" poor British person's accent sounds like but I do not know if it is "really" their accents. Americans do not really have a rich person accent (in pop culture?) but there is a few poor person accents/ speech mannerism.
Anther thing might be jargon. I am a network engineer and there is jargon that people of my profession use that outsiders do not use correctly, that I would be able to somewhat tell by speaking to them. I do not know if this would apply to the different classes, i.e. rich people talking about their polo horses and yachts and poor people talking about whatever they talk about.
Thanks!
[Answer]
"Rich" and "poor" are not in themselves social classes; there have always been rich commoners and poor noblemen. For example, the main character of Théophile Gautier's [*Captain Fracasse*](https://en.wikipedia.org/wiki/Captain_Fracasse_(novel)) is a poor nobleman. Conversely, the titular character of Molière's [*Bourgeois gentilhomme*](https://en.wikipedia.org/wiki/Le_Bourgeois_gentilhomme) is a rich merchant who fancies himself a nobleman; with immortal lines such as *"for more than forty years I have been speaking prose while knowing nothing of it"* (upon learning the difference between poetry and prose).
Monsieur Jourdain's bafflement is the key to the question: in order to pass for a member of a class to which one doesn't belong one needs to *learn* and *practice* how the members of that class speak and behave. There are people who specialize in such education, a famous example being Professor Higgins in George Bernard Shaw's [*Pygmalion*](https://en.wikipedia.org/wiki/Pygmalion_(play)) (better known to modern audiences as [*My Fair Lady*](https://en.wikipedia.org/wiki/My_Fair_Lady_(film))); the plot of the comedy revolving around Higgins's wager that he could teach "a young flower seller woman with a strong Cockney accent, to speak so well he could pass her off as a duchess at an embassy ball" (words from Wikipedia).
In the real world, actors routinely employ professional help to teach them to speak and act like people from different social classes or from other lands. When you see Jenna Coleman playing Queen Victoria in the [TV series of that name](https://en.wikipedia.org/wiki/Victoria_(British_TV_series)), you see her putting on mannerisms and a manner of speech which are not in the least natural to her. She had to *learn* how early 19th centuries English aristocrats spoke and behaved.
The point being that one can study and practice to speak and to behave like a member of a different class. And make no mistake, it is as hard to learn to speak and behave as a member of a lower class than one's own as it is to learn to imitate a member of a higher class.
That leaves the most difficult difficulty, namely that in many cultures the upper classes were a relatively close knit community, and the imposter would immediately stand out as lacking the expected social and family connections. That's why, for example, when Alexandre Dumas's [Edmond Dantès](https://en.wikipedia.org/wiki/Edmond_Dant%C3%A8s) arrives upon the Parisian scene with his newly found wealth, he doesn't try to pass for a *French* aristocrat, but rather uses the *foreign* title of [Count of Monte Cristo](https://en.wikipedia.org/wiki/The_Count_of_Monte_Cristo), explaining why he behaves like an aristocrat and mingles in aristocratic circles without actually having the social links to the local aristocratic society.
[Answer]
It depends how deep you want the deception to go. Are you trying to **fool society at large** or are you trying to fool a **small group of people in a more intimate setting**?
For the first one, I'd say its very realistic. Basic acting skill and lessons along with help from an "insider" who is familiar with the culture and class you are attempting to imitate are probably enough. Why? *Because usually other people just don't care.* The vast majority of people focus most of their attention on themselves or a limited amount of people close to them, and will likely forget your face within 24 hours if you only meet them once, and forget you exist (except for in a vague sense) within a week. If you can influence people's first impression with a proper handshake and a good wardrobe or whatever, half the battle is already won because the thing that will stick in their mind is "fancy suit guy with a monocle" instead of what you actually said or your exact mannerisms and accent.
For the second one--fooling people in a close setting--I'd say the answer is no. Tricking close acquaintances or people you live with is near impossible, because whether people want to or not, they will begin subconsciously (or consciously) analyzing your every move, mannerism, decision, etc. To convincingly pull this type of 'deep cover' off, you need to be extremely talented and have had extensive training and in-the-field experience, and even then, it's often not enough. For example, take a look at how the CIA operates. Instead of training spies and sending them into deep cover, they usually focus on making people who are already in a useful position into spies or informants (willing or unwilling). It is much easier to, say, blackmail or covertly convert someone who already moves in the circles you'd like to infiltrate compared to training someone convincingly enough that they can enter the circles with their own ability.
[Answer]
### Accuracy is not only achievable, it's not even necessary
Making something convincing is not the same thing as making it accurate. People have successfully pulled off outrageously audacious scams in the past, some sporting enough very obvious red flags it's hard to see how they worked.
Sometimes it's a convenient fiction someone powerful uses as a flimsy pretext to cover for something they were planning to do all along. Like [this kid](https://en.wikipedia.org/wiki/Lambert_Simnel) tricked out into a prince by the actual brains behind a rebellion. Or [this man](https://en.wikipedia.org/wiki/False_Dmitry_I) who appears to have been in the right place at the right time (for a short while, anyway).
Sometimes someone manages to just be very convincing. Karl [probably wasn't Louis XVII](https://en.wikipedia.org/wiki/Karl_Wilhelm_Naundorff) but managed to convince some folks who actually knew the man that he was. Frédéric managed to [convince a family](https://en.wikipedia.org/wiki/Fr%C3%A9d%C3%A9ric_Bourdin) he was their long-lost son, even though he was ten years too old and the wrong color eyes. [Frank Abagnale](https://www.youtube.com/watch?v=vsMydMDi3rI) manage to pass himself off as a doctor and an airline pilot despite not having a day of training as either. [Vincent Richardson](https://www.chicagotribune.com/news/breaking/ct-kid-cop-vincent-richardson-arrested-again-20210211-53hreeim7je3hedl2n3qz6sx7u-story.html) made jaw-dropping headlines as a teenager who was so good at posing as a cop he actually worked a shift as one:
>
> Richardson has a long history of impersonating the police, beginning when he was 14. In that incident, in 2009, he was so convincing that he was assigned a radio and went on patrol with a real officer for more than five hours on the South Side, driving a squad car and even making an arrest before police caught on.
>
>
> Then-Mayor Richard M. Daley furiously called out police. “Where is the desk sergeant? The field lieutenant? The captain on duty?” he said. In all, 14 officers, including the captain running the watch during Richardson’s shift and seven sergeants, were brought up on departmental charges, according to an Internal Affairs report on the incident obtained by the Tribune under a Freedom of Information Act request.
>
>
> The report faulted supervising officers for being unaware of Richardson’s presence, while the patrol officers were taken to task for not noticing he was an impostor and not properly notifying their superiors to the presence of an officer from another district.
>
>
>
Having a good story helps. Knowing how to conduct yourself really helps. But it's not necessary. [Charles Ponzi](https://en.wikipedia.org/wiki/Charles_Ponzi), who made the Ponzi scheme famous, has a plausible-sounding explanation for why he needed your money now; that was all it needed to be. The fact that, if he was actually doing what he said he was doing (buying and selling postage stamps) he must have been moving around several times more stamps than actually existed was documented by people looking into him. *It didn't matter.*
I see nothing implausible about this in the least.
[Answer]
Any aristocracy originates as a sort of Mafia. For example, in 1066 Don William, of the Normandy Family, decided to take over the territory of the Godwinson Family, aka England. Having become Boss, he divided the country between his caporegimes (barons), who in turn allocated territories to made men (knights). William's consigliori, Lanfranc, became Archbishop of Canterbury.
Anyone who belongs to a Mafia needs to know whom to trust: *who is one of us?* When the Normandy Family took over England, it became customary for a knight to send his sons to the household of a baron, where they would serve as pages and, later, squires, where they would learn the manners expected of a made man. They would only be made (i.e. knighted) if the caporegime thought they were suitable. In many societies, passing as an aristocrat would be as difficult and dangerous as passing as a made man in the Sicilian Mafia.
[Answer]
I would approach the problem as by treating "class mannerism" as a generic "cultural" thing.
If you're somewhat familiar with the target culture, it will be easier for you to adopt whatever they do. Contrast with a culture you're totally not familiar with: you'll likely be doing trial-and-error to find the correct way to do stuffs. It may also take some time before you look natural doing it.
Immersion and habituation also plays a role: knowing what should be done does not equal doing it automatically and appropriately. Even when you can mimic some quirky habits, you might still struggle to fake a spontaneous reaction.
---
The same principle works against you. If the people you're trying to fool is very familiar with the target culture you're trying to portray, you're going to get exposed much sooner.
[Answer]
I believe that it is difficult, but just how difficult it is depends on the particular society.
* You mentioned which fork to use for the appetizer, but how about knowing what is (and what isn't) appropriate small talk at a dinner party?
* Then there are common cultural references. Most of us know that "Use the force, Luke" is about trusting your instincts, not about using brute force. But if you hear *coming out*, do you think of sexual orientation or debutantes?
* Knowing how to deal with staff, except for those who *have been* staff themselves (and even those might have problems). How do you react when you are in your skivvies when the skivvy comes in?
Much depends on just how much status is inherited in your society (for practical purposes, not legal ones). And also about the size od the upper class. If everybody who matters gets introduced by somebody who has been at Ascot during a previous season, that lack of connections will show.
[Answer]
As an example see George Bernard Shaw's play Pygmalion, and the broadway musical "My Fair Lady"
See also Heinlein's novel "Double Star"
Faking a class requires little more than some acting ability, and training by someone familiar with the class.
The greater the class difference, the harder it is.
I suspect that for a well to do person to "go slumming" would be more difficult than the converse. Depending on how great the difference, accomodating the general increase in dirt, much closer spacing, smells, bad food and much greater contact time.
E.g. you come to an inn and you are expected to share your bed with 3 other individuals as well as sharing their vermin. Food may be bland, very plain (boiled grain). Meat may be bad.
Being in close contact most of the time with others, you cannot let your act slip. This puts on enormous pressure.
[Answer]
One thing that has not been covered is reasoning. Different classes receive different education and have different life experiences. This affects reasoning in many ways, including subconscious decisions. You might be interested in reading [this paper](https://pure.mpg.de/rest/items/item_2019301_7/component/file_2062610/content). It is a meta-study of literacy and its effects on cognition.
If Luria's data are correct (covered in the linked paper), it may be harder for an educated person to an illiterate with little to no formal schooling. People without formal education base their reasoning on very specific knowledge about their environment and lifestyle. For example, they tend to group things based on their purpose, utility, or typical usage (educated people tend to use formal categories). This is very hard to fake. In comparison, learning more abstract forms of reasoning is relatively simpler as it involves studying theoretical concepts that can be applied to a wide range of situations.
It is important to note that uneducated people are no less intelligent or smart than educated people. They just think in a slightly different way. Moreover, these differences show only in specific contexts.
However, if an impersonator cannot simulate these differences they will be perceived as strange. A reputation of an 'eccentric' may work in some situations but it may be undesirable if the goal is to be indistinguishable from average members of the target social class.
] |
[Question]
[
Wait ... what?
Basically, this: Most land predators on Earth use their mouths to kill their prey. That is, they have to stick their precious, irreplaceable heads into harm's way every time they want a meal. I speculate that this has an effect on how ... tentative predators can be. Again, wait ... what? I've watched a number of nature videos, and there is often a **lot** of backing and filling and trying to get behind the prey before making the big rush.
Now imagine a new predator. Think a ravenous kangaroo with a spiked tail. Its attack is to rush up close to the prey then swivel, crashing its cruel spikes into the beast, laming it and causing blood loss. Its head never gets within range of the prey's desperate counter-attacks.
So here's the question. **Does it make sense to posit that this (um) "Velocikangaroo" would be more insanely aggressive than your typical mammalian predator, because its attack doesn't risk its head?**
Note: I'm ignoring the elephant in the room, ie humans. Humans are not obligate carnivores, and they are psychologically weird anyway, so they don't count for this exercise.
[Answer]
Instead of a velocikangaroo, why not go straight with the Velociraptor from the Cretaceous? One of the reasons why the Therapods (the branch of dinosaurs that evolved into birds) were capable of surviving in a flying form was the pronounced development of their breast muscles and the sheer power they could bring to bear on displacing enough air to take flight.
Velociraptors on the other hand used those muscles very differently (according to what we've extrapolated from the fossil record); to grab their prey. Yes, they were ambush predators, but instead of using their heads to strike, they used their arms, then used their heads to make the kill once they had hold of their prey.
That said, I don't think the protection of their heads factored into their style of attack so much as the benefit of being able to see what they were doing with their arms and therefore being more agile; something your velocikangaroo isn't.
Truth is, risk of injury is more a factor in fighting over females, or defending territory against one's own kind. There the match is even, and the risk of damaging yourself and not being able to hunt is too great. On the other hand, if an ambush predator is worried about its head when hunting, it's just more likely to go after smaller or weaker prey. Hunger is more of a factor in hunting aggression than knowledge of one's weaknesses and that means that you're likely to see a wide variety of aggression levels and risk taking even within the one species.
[Answer]
**Not really, no.**
Within the scope of hunting prey, predators are doing this not because they like it: they do it as a means of survival. If there were a species which expended almost as much energy obtaining their food as they earned eating it, they would not survive long. With that in mind, it is easy to see why predators typically go for ambush tactics, only engaging in high-intensity chases/ hunts when absolutely necessary.
As such, the lack of "aggression" as you see it in today's predators may not be completely due to a fear of injury, but also to minimize effort. Going all out and smashing your prey to a pulp may sound attractive if you do not risk injury, but you will probably expend a lot of energy doing so - where's the benefit?
If your Velociroopter (you're welcome) became such an advanced killing machine that it were able to kill its prey very efficiently, it is plausible to suggest that it goes on killing for sport/ fun. In this case, perhaps it would display hyper-aggressive behavior on such sport kills.
[Answer]
>
> Does it make sense to posit that this (um) "Velocikangaroo" would be more insanely aggressive than your typical mammalian predator, because its attack doesn't risk its head?
>
>
>
I'd say that it depends. If the prey animal defends itself and bites off or maims your Velocikangaroo's tail (or one of its limbs) then the Velocikangaroo will be unable to hunt and die of starvation. In other words, its main hunting weapon is just as essential for survival as its head.
Another animal which attacks with its tail:
[](https://i.stack.imgur.com/AOzo8.jpg)
It does not do spinning attacks... the tail strikes to the front where the scorpion can see. While its dinner is busy parring its pincers, its tail strikes from above. The pincers are also armored and tough.
I think you would need an animal which can deploy a reusable ranged weapon.
[This spider](https://www.youtube.com/watch?v=BUELYcGDCc4) doesn't wait for you to fall into its web. It throws the web at you instead!
The [velvet worm](https://www.youtube.com/watch?v=LY8TgD6-7kg) shoots glue.
The spitting cobra shoots venom (and it aims for the eyes!)
The [Komodo Dragon](https://www.youtube.com/watch?v=iw7y4_Zy5bs) has armor and a venomous bite (it's pretty vicious)...
You could also have a slightly less peaceful kind of deer which impales you on its horns and then eats you...
[Answer]
[](https://i.stack.imgur.com/LbI1e.jpg)
Eagles are not especially aggressive.
Also, cats and back-leg kicks: <https://www.youtube.com/watch?v=uBBwdtr14rM>
Cats are not especially aggressive.
The way to make a predator aggressive is to make it perceive a threat to its territory/mate/offspring/food supply. Boars, mother bears, alligators around its nest, ... hornets!
[Answer]
Animals that can use tail attacks normally do so as a defensive move against an attacker, they also do this while standing side-on so they can also see the attacker's position.
I think crocodiles can use tail attacks but again I think this is a defensive rather than offensive attack pattern for them, but am happy to be corrected on this point if anyone has more experience of crocodiles there aren't a lot of them wandering around my part of the UK. :)
As mentioned by others, a spinning tail attack would require the attacker to lose sight of the prey and have to predict where the prey is going to be for the tail to strike in the intended place.
If the prey changes direction or elevation of the target area, stops, stumbles, jinks, zigs instead of zags, the attack will miss and Velociroopter (I like that name) ends up spinning out of control then flat on its face in the dust with its tail in the air gently waving in the breeze like a flag of disappointment.
However give your Velociroopter the claws common to Velociraptors and the tail as a backup defensive weapon, or perhaps make the tail strike over the head or shoulder akin to a scorpion's sting so that the Velociroopter does not have to lose eye contact with the prey to strike, and you'd have an effective predator.
BTW, is someone going to draw this?
Xenocacia came up with Velociroopter, I reused it as it is epic.
[Answer]
There are reasons why predators attack from the back:
* head is in the front: you either look where you are going or watch out for your back. You cannot do both at the same time.
* chasing has the clear advantage of following the prey
Now, imagine I am the dumbest prey in the world: it just takes me a sudden stop or deviation, while this fantastic kangaroo has overtook me and is charging its tail, to avoid the blow. And moreover the kangaroo won't even see me going away until I am more distant from him then I was when he overtook me.
Shortly said, your kangaroo would struggle to survive.
But your question is about the psychology of the animal: chasing a prey is already a considerable effort, overtaking it is with good reasons even a greater struggle. Also, swinging your tail while in movement and keeping balance is not a trivial task (unless you want to fall down and being rolled over by your running prey). Definitely, I don't see any push for this animal to become overly aggressive.
[Answer]
# But not all ocean predators use their mouths.
As requested, some use their tails.
* Some groups of orca [tail slap](https://www.youtube.com/watch?v=ETL1fwcDUQ4) the bait ball to stun their prey before picking them off.
* The thresher shark does [something similar](https://www.youtube.com/watch?v=QCXD_clMLeA), also tail whipping to stun their prey.
There are advantages to doing this in the water over doing it on land, including shockwave propagation due to the incompressibility of water meaning they don't have to be particularly accurate to hit a large number of targets, but your intended principle is there for you to work with.
Given a pack hunting Velociroopter that rounds up the prey as ocean predators do, rather than land predators who tend to run it down, then attacks a target with the tail meaning they less vulnerable to horns or other defences. Perhaps it could be a viable hunting technique on land as well.
As for your primary question: **What would be the personality of such an animal?**
Controlled, sociable, pack hunting. Probably high intelligence with solid communication. Definitely not a nutter. In fact less aggressive, it's fundamentally a lower risk attack.
[Answer]
The loss of use of an arm/leg/tail means almost certain death for a wild animal, predator or prey, so its not just the head that is precious.
If you use a big spiked arm/leg/tail to attack and that gets disabled then you can no longer hunt and you die because you cannot eat. If you use it for defence then you die as you can no longer defend yourself from predators, who will naturally look for weak or injured prey.
[Answer]
I think that **there is no general effect** (read: justification for psychotic behaviour) **because the issue balances itself** in the sense that the head becomes as armoured as needed/possible given the rest (think of a shark's eye protected by a membrane an instant before biting down, thick skulls in headbutting herbivores like pachycephalosaurs and rams): Losing a limb is just as deadly as losing a head (or jaw!) to a lion, the dying just takes a few extra days/weeks. Note also fighting male giraffes striking with their necks(! occasionally breaking them), not those rudimentary horns they have.
But possible adaptations, of which I like the last best:
**Shockwaves?** You said "land-based" which rules out a whole class of attacks using shockwaves in water, most notably pistol shrimp (micro-cavitation!), "hammer" mantis shrimp, tail-slapping orcas, echo-location-type-to-the-max type bursts in dolphins; and a few electric shocks using the conductivity of water (eels, rays, ... ). I seem to remember a few "How to Train Your Dragon" dragons use shockwaves. And I think some bats do the echolocation equivalent of dolphins, to inhibit their prey.
**Pincers**
This is the obvious thing, in everything from praying mantis (well, kind of a reversed pincer) to already-suggested scorpion (where many have weak venoms and rely on their pincers alone --- it's those with heavy stings and skinny pincers that tend to be dangerously venomous). Also "spearer" mantis shrimps [yeah previous pistol and "smasher" mantis shrimps use adapted forelegs as tool but the use/effect isn't grabbing.]
**Projectiles?**
Some snails shoot a calcium-based arrow into their partners: Being hermaphroditic, they benefit from being "the male" in a copulation because the genetic/offspring benefit is the same (see RA Fisher and sex ratio theory) but the investment is much smaller ('male' means 'having the smaller gametes', i.e., sperm not eggs). So this arrow is full of sex-changing hormones, no reason why your creature couldn't re-grow this arrow faster than a snail (hah!) and cover it in venomous proteins/peptids instead of hormones. These are easier to aim if in the head (looking=aiming) than in the tail (3D measurement/estimation of relative positions and angles of observing head, prey, and aiming tail) or possibly the body. (Note scorpion's sting strikes just in front of its head, no sideways only some small arc of possible strike points low/near to higher/further, so that head is in the 'danger zone'; but that head can thus verify hit/miss.)
Spitting venom in cobras is defensive, not offensive (a running-away or surprised prey isn't facing them, skin is impervious). So similarly your projectile attack will work well on mollusks and amphibians and unprotected humans, but anything scaly (or possibly even excessively hairy) will not be penetrated by the dart: Pangolins and paladins are safe.
[Answer]
The real elephant in the room is that their *attack is to rush up close to the prey then swivel* (!). **Its attack puts it in the position every other predator wants it in.** Plausible only if your world lacks felines and other animals with instinctive kill strikes from the rear.
Let's look at a ... (*the only* ?) large creature that had a tail as a weapon, the [Ankylosaurus](https://en.wikipedia.org/wiki/Ankylosaurus). **A quadruped that used its tail for defense.**
[](https://i.stack.imgur.com/DjFni.png)
Notice that it also had armor throughout, with special attention to the neck plates. It also wields a bludgeoning weapon without spikes that can neither break off nor injure itself with.
[](https://i.stack.imgur.com/tIWxF.png)
The psychological effect of this would be an animal that does not want to use this mechanism unless absolutely necessary due to the high probability of injuring itself, and said creature is unlikely to have evolved, based solely on the lack of precedent in the animal kingdom (no animal has spikes that point at itself). It already has a hard enough time curling up and getting comfortable in bed.
Hunting ass-backwards *is*.
[Answer]
I'd like to offer an additional insight into why heads typically contain the weapon of choice, and maybe some alternatives that fit what we're familiar with.
First, evolution tends to favor **efficient energy expenditure** and **low complexity**. You don't see too many body parts exposed to wear and tear that are also complex. It's the same mentality engineers use all the time: The more a piece gets used, the more chances it has to break, and the harder it is to fix it. Most carnivores require some sort of appendage to tear apart food, and **a jaw is a wonderfully simple way to concentrate a lot of force on a small area** to do just that. Well if you've already got that much power in one spot, **what's the benefit to developing *more* power in a *second* spot?** All you need to do is restrain your prey (with those same limbs that are already great for travel) and then the jaw can do all the work. Multitasking!
Second, there are plenty of carnivores out there that don't rely on their jaw/head for the kill. Some snakes strangle their prey. Many predatory birds kill with the impact of a dive. Lots of sea creatures hunt with tentacles or stingers. **They've all adapted these methods because** in their particular cases, **there is some kind of advantage**. For example an octopus pries open mollusks with its tentacles, because even a strong jaw isn't powerful enough to defeat them otherwise. A falcon kills with outstretched talons so its eyes can keep the target perfectly in view during its 120Mph dive.
But to your original question, **does this affect their *psychology*?** Long story short, there's no good way to answer that. They certainly aren't *more* or *less* aggressive on the whole, because they only risk their necks as often as they need to for food, the same as everything else. *Could* they? Sure, probably. But they'd have nothing to gain from it, other than social status, which isn't a thing for most animals outside of mating.
Now there are plenty of creatures which *are* hyper-aggressive for various reasons. It just happens to have little or nothing to do with their preferred method of killing; As others have mentioned, it's usually to do with mating or territory. So invent whatever reason you see fit to make this velociroopter (lol) aggressive. Features that might help shoehorn that trait in would be things like having the mouth separate from the head, or making it have to consume/digest its prey slowly. The process of eating might make it vulnerable somehow, so it has to be able to scare off or intimidate potential threats first.
**TL;DR** Body type has no direct correlation with psychology, in the world as we know it. The practical advice is, don't go too crazy designing an aggressive creature, just design a creature and then describe why its environment *requires* that it be aggressive. Remember that even the most safely-built creatures don't stick their neck out more often than needed for food, mates, and territory.
[Answer]
One serious limitation to the velocikangaroo is that it cannot be looking while it strikes. It literally must flail blindly to make its killing blow. Meanwhile, the prey can see what they're doing. It would be quite difficult to land a good blow on any nimble prey.
Using jaws allows you to use simple guidance algorithms all the way into the point where you're close enough to need to close your eyes to protect them. Remember, when we try to catch a baseball, we don't move to the optimal spot right away. We move in a way which keeps the angular motion of the ball linear with respect to our own eye. It makes the guidance algorithms easier, so you can have faster processing.
If you really wanted to hunt this way, you'd have to do two things. The first is you'd need to make your weapon expendable. A predator that can't hunt prey is as doomed as a predator whose face got hurt in an attack. The second thing is you're going to need an attack which doesn't require you to look away from the enemy.
I suggest a bioweapon akin to the Chinese dart:
[](https://i.stack.imgur.com/pMkXS.jpg)
Wielded properly, this operates like your spiked tail, only one strives to maintain both energy and angular momentum at all times, so it's much more effective if you miss. It's [quite a sight to behold](https://www.youtube.com/watch?v=8IPl2tFNihc). It's also a cheap enough structure that a predator might be able to afford to lose one or two without breaking the energy budget that a predator needs to stay alive.
[Answer]
**Think baseball**
>
> I speculate that this has an effect on how ... tentative predators can
> be. Again, wait ... what? I've watched a number of nature videos, and
> there is often a lot of backing and filling and trying to get behind
> the prey before making the big rush.
>
>
>
Your instinct to think about humans was the right one even though you don't want to consider humans particularly.
What do humans have that only a handful of other animals do?
1. Ranged weapons like bows and arrows, slings and rocks, and atlatl to throw spears.
2. Tool use.
The answer, I think, comes from baseball and not zoology, as I explain below.
**Bio-projectiles**
@Peufeu notes several animals that use bio-projectiles (spit or glue or spider silk), and another class of bio-projectiles could be numerous disposable spores or spines that could be hurled at prey.
Another bio-projectile would be poisonous feces dropped by a bird (or better yet a whole flock of birds since birds in flocks tend to poop in unison at roughly the same target) from the air on you. Poisonous or caustic or acidic poop from a whole flock of carnivorous killer pigeons at once is something you have to take seriously. It would be the moral equivalent of napalm.
**Tool use**
The other option is tool use.
Quite a few animals use tools (a few even turn other animals into zombies to do their bidding for them), rather than actually attacking with parts of their bodies.
Tool users, especially those that attack at range, can afford to be psychologically much less tentative because they aren't putting themselves at risk.
Is this far fetched for a much more primitive animal than man?
No.
For example, have you ever had a squirrel throw acorns at you? If you haven't, I absolute assure you that the do it, ruthlessly, with impunity, from high in a tree where you can't get them. They do it to dogs too (something I rather admire them for doing).
Suppose that your velocikangaroo, rather than using his tail like a mace, used its tail which had a sling-like pouch at the end of it, like a baseball pitcher to throw medium sized rocks at prey at 200 miles per hour at distances of 100 feet with deadly accuracy. Now that is a predator who might not be timid at all, and that predator, unlike those who used bio-projectiles, wouldn't have to pay much of a biological/energy supply/healing cost to gather up unmodified medium sized rocks to stack up and throw at prey. Thus, the velocikangaroo could be a tool user simply by throwing ordinary, easy to find rocks, without being a tool maker, which is a much more sophisticated thing.
You'd also want to give your velocikangaroo kean, stereo hearing to locate threats and prey before they go to close and accurately aim at them, and keen binocular eyes to aim with, and a good sense of smell (again to prevent ambush attacks). Color vision might be unnecessary for an obligate carnivore since color vision can actually make it harder to see camouflage and the purpose color vision evolve for (distinguishing ripe from not ripe or rotten fruit) isn't important to a carnivore.
Finally, he'd still have to be pretty fast because if he ran out of ammo he'd probably want to run like hell.
] |
[Question]
[
Suppose I wanted to form a new sovereign state right now, can I still be able to do it? I can find people to run the government, make laws, build roads, erect commercial and residential buildings and most importantly say I got connections in UN club and many leaders are willing to recognise my new country. Is there any place left on the planet for me to construct my country? I'll hire mercenary to defend my border. Comment below if I leave out any crucial details and feel free to correct my English. Currently in process of designing my own flag...
[Answer]
There are in fact areas in the world not claimed by any country. The area of [Bir Tawil](https://en.wikipedia.org/wiki/Bir_Tawil) in Africa is between Sudan and Egypt and neither country wants it.
2,060 km² of landlocked desert in the middle of nowhere with no roads, no rivers and no known natural resources. But at least it is unpopulated, so you won't have problems with indigenous population.
[](https://i.stack.imgur.com/iiBDq.jpg)
Why does neither want that area? Because they can't agree on where the border between their countries is. Egypt claims the border is a straight east-west line while Sudan claims the border is the zigzag line you see above. Both countries want control of the much more valuable Hala'ib Triangle with the city of Hala'ib. Claiming control of Bir Tawil would mean to accept the border proposed by the other side and giving up their claim on Hala'ib. So should you settle in Bir Tawil and form your own nation, no side will interfere with you.
...at first. Should the question of the Hala'ib Triangle ever get resolved, the "losing" side will have no reason to not claim Bir Tawil and will likely try to evict you. Also, when you are really successful in building your nation, it might get more valuable than Hala'ib and both countries will start to argue about Bir Tawil instead. And no matter which side wins, you will lose.
[Answer]
Being Czech sometimes helps answering these questions:
**You can do it. Just follow Czechoslovakia example:** 1st January of 1993, Czechoslovakia was no more. Two new sovereign nations came to life: Czech Republic and Slovakia.
Steps to reproduce:
1. Have a country which is actually built by more nationalities, or from more logical parts. Examples: USA, Switzerland, Great Britain
2. Form a [federation](https://en.wikipedia.org/wiki/Federation) from these parts. They share president, but local governments are partly independent
3. Make politicians talk about the split
4. Alternatively, you can [let people vote about the split](https://en.wikipedia.org/wiki/Scottish_independence_referendum,_2014)
5. Make politicians and/or people agree on the split
6. Split everything. Currencies, debts, land, people
7. You have two sovereign republics now.
Both Czech Republic and Slovakia are recognized by UN. Both countries are in European Union. Because both agreed on [Schengen treaty](https://en.wikipedia.org/wiki/Schengen_Area), the borders are now just on the paper.
And once Czech republic adopts monetary agreement, both countries will use the same currency again.
Of course, by following this example, no new land was taken. Although we could say that both Czech and Slovak republic were "new" on map, they made agreements on how to split historical duties.
And after that, even the [domain](https://en.wikipedia.org/wiki/.cs) was gone ...
[Answer]
You probably won't get any recognition assured before you get to choose the place.
For example, the creation of [Israel](https://en.wikipedia.org/wiki/Israel#U.N._partition_resolution) was well accepted by the main powers of the time, but the local countries were, to say the least, a bit reluctant. We are now almost 70 years later, and the problem isn't completely fixed.
You can see the struggles of "countries", who, for historical (e.g. [Taiwan](https://en.wikipedia.org/wiki/Taiwan#Political_and_legal_status)) or ethnic (e.g. [Kosovo](https://en.wikipedia.org/wiki/Kosovo#Foreign_relations)) reasons wanted to secede from their former countries. But in the corresponding wikipedia articles, you can see how that isn't so easy.
If you want to create some country from nothing, you need some land. And most of the land on the Earth belong to some country already. In fact, apart from possible small rocks in the middle of the ocean (and even not all of those), the only remaining free land is Antartica. Which, incidently isn't a great place to start a new country: getting the economy running is going to be tough. And you'll probably end-up alone. Plus there are some [international treaties](https://en.wikipedia.org/wiki/Antarctica#Politics) preventing an actual possession of the land there. Buying a piece of land in a country isn't enough, you'd be in conflict with that country.
I cannot think of any example now, except to some extend Israel, but see the previous note. You could probably buy some land in a failed country, or a country with a dictator willing to sell away some part of his country, or even the whole.
Yet the easiest, would probably to follow the example of [Sealand](https://en.wikipedia.org/wiki/Principality_of_Sealand). You could build yourself a large floating city in international sea. And if you got the support you claim, you could make it into an independent city. That would be a strange experiment, but it would require a lot of political support, and probably good funding to get started. There are already [projects of floating cities](http://news.nationalgeographic.com/news/2012/07/pictures/120730-future-floating-cities-science-green-environment/). You could get one, and with your political support have it placed in international seas and get recognised.
[Answer]
All the good land on Earth is taken, so you have to create your own. Build an artificial island like the Palm Jumeirah in Dubai:
[](https://i.stack.imgur.com/rDgm3.jpg)
The technology to create islands by piling up sands in shallow seas doesn't exist for long. So far it was only used in waters very close to natural shores, so it was quite obvious that they were the territory of the closest nation. But there is no precedent yet for a private person creating one in international waters.
International waters start outside the [contiguous zone](https://en.wikipedia.org/wiki/Territorial_waters#Contiguous_zone) which is 24 nautic miles away from the shore. To be save from any reasonable claims, you should go far enough away from the coast to be out of the [exclusive economic zone](https://en.wikipedia.org/wiki/Exclusive_economic_zone) which ends at 200 nautic miles. To be completely sure that nobody finds any reason for conflict with you, you can even go to 400 miles, so your economic zone will not intersect that of any other country.
When you import the soil from the mainland, the nation you take it from might claim that because you used their soil, your island is their territory. So to be safe from that claim, scoop up dirt from the ocean floor.
Unfortunately the international waters are usually very deep, so getting enough soil piled up to create a mountain which reaches above the water surface will be a quite challenging project. The guys at [earth science stackexchange](https://earthscience.stackexchange.com/) might be able to suggest you a place where the water isn't too deep but still far enough from the nearest natural land.
[Answer]
# Create new land
Volcanoes occasionally create new islands. Loihi Seamount is an example of this. It's an underwater volcano south-east of Hawaii. Being close to Hawaii, when it emerges from the sea, it will of course become US soil.
Imagine a new volcano in international waters. Who would claim it? Such a situation has not occurred in living memory. It would be a scramble.
Assume you were able to get there first with a small army and plenty of equipment. You could perhaps defend it against established nations and other privateers. If you have enough military clout, and something to trade, you might perhaps forge alliances and eventually become recognised by the UN as an independent nation.
[Answer]
A group you may have heard of called ISIS has attempted to do so in the former territories of Syria and Iraq. This illustrates some of the principles and pitfalls of creating a new nation.
First, you have to actually secure some territory. Most of the Earth's territory has already been claimed by someone, so the first thing you need to do is have the ability to establish your own, stronger claim. Being in physical possession and able to stop all comers from taking the land you claim is vitally important. This requires hard power, the type you get with guns and manpower.
Then you need to have the people in "your" territory agree to be ruled by you. Sometimes the people might not agree, but if you have enough hard power to establish yourself in the first place, then you also have the means of making people see things your way.
Next, you need to have working institutions inside your territory to actually run and administer things. A system of laws, courts to enforce the laws and a well defined system of governance are important, otherwise you are just a failed state like Somalia (where a warlord might only be in charge of the area he can physically control, and is constantly under challenge from other warlords). People crave stability to run their lives and business, so your laws and institutions might not be very much like the ones we understand in the West, but so long as they are generally recognized, enforced and followed, then you are a functioning State.
Finally, in today's world, you also need to be recognized by other nations. This is important since being part of the "club" provides lots of benefits like being able to engage in trade and commerce on a large scale (ISIS can engage in criminal smuggling of oil, but the vast majority of it's "citizens" live from hand to mouth because they have no legitimate outlets for their goods and services).
So would be Genghis Khans have a lot of work ahead of them, most of it starting *after* you gain control of the land.
[Answer]
Very difficult: expect strong opposition from nearby countries. Look how hard Britain fought to stop Sealand (<https://en.wikipedia.org/wiki/Principality_of_Sealand>) from becoming a tax haven. Maybe build a new floating island nowhere near another country?
[Answer]
One possibility would be to buy an island and declare it as your country, but it would be difficult to join UN etc.
The other possibility could be creating a situation like south Sudan to separate a part of Country from the native country, either using religion race or ethnicity as a reason. This would mean you should do your best to make a split between the people in different parts of a country. And if UN (or at least some democratic countries) see that "your people" are discriminated or humiliated or suppressed somehow they will react and maybe this way you could create a new country. A good help would be if the native country was ruled by a dictator or a regime that already suppress (at least parts of) his/its population. You should try to stay before and during the splitting process in the news of democratic countries!
The only difficulty could be if you want also to be the leader of the new country as if the country will be created by a split after a kind of revolt it's hard to know whom will be at the top of it, so you might need some kind of facilitators who are 100% behind you and your own military forces (as you mentioned) so you should prepare all of this very well.
[Answer]
Grab a bunch of people, go live in isolation, choose an aquatic environment, evolve into a new species until you develop gills, then move to the Ocean, find somewhere deep enough, far enough from territorial waters, found your new country.
The only problem is, your flag deep in water may not wave; besides, with little light it won't matter if it's got any design or it's just black. Perhaps you have to give up on your country flag? You don't want a detail to jeopardize your dream.
[Answer]
If the ancient laws are still respected, the first person to reach a newly formed island (obviously volcanic) not in territorial waters would be able to claim it for his nation. If that person were to be a [stateless person](https://en.wikipedia.org/wiki/Statelessness), he would be then able to claim it for himself.
[Answer]
As the recent examples of [Donetsk People's Republic](https://ru.wikipedia.org/wiki/%D0%94%D0%BE%D0%BD%D0%B5%D1%86%D0%BA%D0%B0%D1%8F_%D0%9D%D0%B0%D1%80%D0%BE%D0%B4%D0%BD%D0%B0%D1%8F_%D0%A0%D0%B5%D1%81%D0%BF%D1%83%D0%B1%D0%BB%D0%B8%D0%BA%D0%B0 "Donetsk People's Republic") and [Lugansk People's Republic](https://ru.wikipedia.org/wiki/%D0%9B%D1%83%D0%B3%D0%B0%D0%BD%D1%81%D0%BA%D0%B0%D1%8F_%D0%9D%D0%B0%D1%80%D0%BE%D0%B4%D0%BD%D0%B0%D1%8F_%D0%A0%D0%B5%D1%81%D0%BF%D1%83%D0%B1%D0%BB%D0%B8%D0%BA%D0%B0 "Lugansk People's Republic") (and before that South Ossetia and South Sudan and Abkhazia and Kosovo and Transnistria and Vatican and...) show, it is possible, if you get enough followers, some weapons, support from someone strong and a weak government whose territory you want to base your country at. It will be a bit difficult with the international recognition, but if you persevere, eventually you'll get a full featured country.
[Answer]
The world is a savage place. You can make a new country only if you have the means to defend it against invading nations. If you don't then it is all about if the other countries, not you, want the country to exist.
] |
[Question]
[
This world has 3 forms of faster-than-light travel:
1. Warpdrives don't require destination coordinates. They can be activated and deactivated at any time to move continuously through space. But they are the slowest of the three, and are easily tracked and detected.
2. Wormdrives require precise destination coordinates. The Wormdrive mounted on your ship creates a temporary traversable wormhole that starts in front of you and ends at the destination coordinates.
3. Wormgates are two wormdrives linked end to end. You need one ship at the start of the wormhole and another one at the end.
All three forms of travel work on the same principle. They all require precise calculations tailored to the exact mass of the craft. They all become unstable with prolonged use. This is why the wormholes are closed after use.
My question is can wormdrives, wormgates and warpdrives in this scenario exist without making any of them obsolete?
How could I justify why wormgates need a destination gate? And are there any other redundancies or more efficient ways to use this tech I have overlooked?
This is very much a work in progress and yes I'm over thinking it.
Edit: Renamed Jumpgates to Wormgates for clarification. Reworded my question and added a bit on warpdrives.
[Answer]
**Planes, trains and automobiles**
[](https://i.stack.imgur.com/JuQqm.jpg)
The different forms of FTL travel are the same difference between walking, cycling, driving, and flying on an airplane. The later methods are more technologically advanced. They are faster. But they are also more expensive.
Airports are large and take a long time to build. So they are specialised for long trips. You cannot fly to work in the morning by airplane.
Warpdrives, Wormdrives and Wormgates are like a bike, a car and an airplane. Yes you can in principle use any one for any trip. But some trips are too short to pay to open up a whole new pair of wormholes. And some trips are too long to navigate hyperspace yourself.
**Why do wormgates need a destination gate:** The same reason airports only send planes to other airports. It makes things much easier. By using a target gate and using the same one every time, it becomes easier to send large things through. You also only have to make the link once. So wormgates are longer range than wormdrives.
*The photo is Steve Coogan and Jackie Chan from Around the World in 80 Days.*
[Answer]
1. Risk.
Wormgates are in space and some weasels clear space next to them. Jump is 100% safe.
Wormdrive is risky. You do not know that your travel will not end with a collision with an asteroid right after the jump.
2. Calculation power.
Wormgates have powerful computers and calculate travel precisely.
Wormdrive on ship - You need to make the calculations little rounded. No problem to be couple thousands km from target in space. But if you try to jump next to a planet, then can end in the atmosphere or worse in the core.
And gates can calculate a route to anywhere. Ship - some militaries have good enough computers to do math for 1000 parsecs, but most are limited to 10 LY.
Why use drives then? Military, smugglers with illegal goods and guys who do not want(or can) to pay GATECORP their fees.
[Answer]
The most obvious point here is... how do you use an FTL gate, if the only place you can put the destination gate is within sublight-attainable distances? Woohoo, 10 years to set up the Oort cloud gate!
So, FTL drives are important. They might be outlandishly expensive, but you could build as few as finances allow, and use those to dump gates at the other end... with tourists pouring out the other end almost as soon as you turned them on.
As for having two different FTL drives, that can be chalked up as technology marching on. Even for far more mundane technologies, we often develop multiple competing methods. One is more convenient than the other in most cases, or cheaper to operate (or cheaper to construct). Even if there aren't very many advantages to one over the other, you would see humans invent both just for experimental purposes.
It might even be the case that a company has some long-lived patent on the one drive, and a competitor just sidesteps that with an alternative operating on a completely different principle.
[Answer]
You just described interplanetary and interstellar transports.
The wormgates are awesome for ships without any drives. They take you to and from one planet to another, or even across interstellar distances! But without an internal drive you will be limited to only those gates. Thats fine for many types of transport, but not all.
The wormdrives are for the mainstay transportation to known bodies. You might not want to use a gate because of waiting lines or because the gate is on the wrong side of the planet or the planet you go to doesnt have enough traffic to justify a wormgate. So you use the wormdrive. The wormdrive has to open a hole at both locations so if you dont know the proper location you could end up very far from your intended destination.
Warpdrives are for transport to places where you dont know the exact positions. It may be an asteroid belt, or the distance to the planet is so large and your charts arent detailed enough to know the coordinates at the exacting standards necessary. Or it could simply be an expeditionary action to set up gates or discover if a solar system is worthy of your attention.
Edit: seeing that you want a limitation on the range of wormdrives there's two ways (3 if you combine them):
* to gather data about your destination point requires a minimum scanning resolution, relying on a database can be unreliable as the exact composition of the local area can be different (and all matter changes local space-time).
* you need to open two portals, one at your own position which is easy and one at the destination point. Projecting the power that distance can be HARD. Imagine using a laser at that distance, you need a masssive focussing array to achieve it or else the laser will spread out too much. A Wormgate might be able to pull it off but its so much safer and cheaper to just hold the wormhole open on both ends with a seperate gate.
[Answer]
As I read the question, it's a bit hard to understand what you are asking. Assuming that you mean, How can I justify the existence of these three types of FTL without making any of them redundant/obsolete?
**Warpdrive**:
Say this operates at a level similar to the [Alcubierre drive](https://en.wikipedia.org/wiki/Alcubierre_drive)and StarTrek™. Requires a great amount of power while in operation. Though not so much that it would be out of the reach of commercial enterprises or even wealthy individuals. Also Power requirement scales with ships mass. The larger more massive the ships, the more required power supply to generate and maintain the warp bubble.
Travle time and warp class may be expressed days per light year. Or hours per light year. ie: 20/1 would be 20 hours to one light year, or 90 hours to Alpha Centauri or 3.75 days. Adjust as you see fit :)
**Wormgate**:
Is a stationary structure that must be located in a region of spacetime that is "flat" or rather, free from major gravitational disturbances. usually outside of any major planetary / stellar orbit. As gravitational waves disrupt the formation and stability of the wormhole used as transport. WormGates consume Vast amounts of energy especially upon formation. Far and above what is needed to sustain a WarpDrive. Therefore they are only constructed in systems that have large amounts of traffic between them. Though the power needed to transport ships scale with their mass it is not nearly so great of a curve as warp drives. No special equipment is needed to use a WormGate and any craft may pass though as needed. The structures are needed on both ends so as to:
* Provide a stable endpoint to the space-time tunnel.
* Share the power requirement to keep the conduit open.
* Provide telemetry and to regulate traffic though the endpoints.
Only governments and major toptear corporations can afford to operate WormGates as the infrastructure, technology required are diverse expensive and quite complex.
**Wormdrive**:
Operate on the same principle as WormGates except since the travel is on demand. Thus, they may initiate the worm drive in areas not suitable for a worm gate, though they do still need to be in an area of "flat" space time, and again at any time they chose to virtually any destination they chose. However making jumps to areas they have no telemetry or areas they are light years away on the only intel available is Visual / Radio astronomical data. What is actually in the area when you jump to it may be vastly different than observed light years ago. Initiating a Wormdrive jump requires as much power as does initiating a WormGate connection.Although there is no ongoing power requirement after the jump. Also the computational requirements are much higher as the traveler must computer start and endpoint dynamics not to mention among many data points differences in the relative delta V of there destinations. As with WormGates only top tear Corporations and government / military could afford to operate such devices. Costs are farther above even those of WormGates. Indeed, considering the strategic value of the nature of the technology it is highly likely that it may be restricted to government and Military uses.
NOTE: ships may have WarpDrive and WormDrive, but may not operate at the same time. ***Do not ask*** what would happen if a ship operating a WarpDrive entered a WormGate...
[Answer]
**Largest difference is travel speed**
Worm gate (long distance):
* Can be much larger and have more power generation, wormhole stabilizers, wormhole creators, etc.
* Can connect to a much further distance so the travel speed is much faster.
* Maybe can create wormholes much faster and do mass calibration much faster.
* Maybe can use cheaper components because they don't have to be miniaturized.
* Can be used by crafts lacking wormhole travel.
* If can connect to another wormgate, then can increase the distance even further.
* Maybe the length of the inside of the wormhole can be shorter so the traversal time is faster?
* High precision so that you arrive very precisely at target coordinates.
Worm drive (medium distance):
* Require a long time to stabilize and adjust the formed wormhole, before safe traversal can occur.
* Precision is lower especially over larger distances, so you probably have to use FTL once more to reach the desired destination.
* Maybe another ship can acts as the other end of a wormgate and increase the travel distance. Useful for reinforcements. But this might have a long setup time.
Warpdrive (short distance + combat)
* Can be activated quickly so more useful in combat or for short distances.
* Maybe a difference in price compared to the others?
Thoughts:
* Maybe most civilian crafts only use one of the FTL types, because of cost, weight and volume.
* Maybe have specialized carrier vessels that can transport smaller craft?
Edit:
Maybe the wormdrive can open many small wormholes in succession to try and find the correct settings to arrive at the desired destination. Probing the destination...
[Answer]
1. **Wormgates/Wormdrives have a minimum practical range.**
So one would want to use Warp for insystem use, nobody wants to spend six months on the way to Mars when Alpha Centauri is just an eyeblink away.
2. **Wormdrive is slightly inaccurate, destination Wormgates stabilize the exit point.**
Say a Wormdrive is only accurate to 0.01% of the traveled distance. So a jump to Alpha Centauri could easily be off by the Earth-Mars distance.
3. **Wormgates can be relatively close to each other, in orbit.**
Something about the calibration sets them apart for paired connections, maybe. So if there is no Wormgate between A and B, it is much cheaper to take the A-C, C-D, D-E, and E-B gates if such a chain exists.
This gives you:
* Civilian/Commercial Gate Craft
Freighters, passenger transports, and the like. They travel *only* through gates, with relatively weak maneuvering thrusters to get from gate to gate. By far the cheapest mode of travel, a can with a little flight deck attached. Endurance might be measured in hours; passengers get seats rather than cabins. No military use, unless both sides of the gate are firmly secured.
* Civilian/Commercial and Military Wormdrive/Warp Craft
Offensive warships and scouts. They can use the Wormdrive to travel to unexplored or hostile systems, and maneuver there with Warp. The most expensive craft, and those with the smallest payload, since they have to carry two FTL drives and usually long-term life support. They *can* use Wormgates, but they are not competitive if the trip is *only* from gate to gate.
A special subtype are Wormgate emplacement ships.
* Civilian/Commercial and Military Warp Craft
They can travel long distance by Wormgate, and insystem by Warp. Cheaper than the combination designs above, so they get better payload and/or better warp speed. A defensive space force has just these, since they carry more bang for the buck.
* Wormdrive-Only Craft do not exist (or they are prototypes)
If Wormdrive is "easier" than Warp, then Wormdrive craft might be required to deploy Wormgates to a new system. After the arrival scatter, they spend a *long* time traveling sublight to the planet or whatever.
[Answer]
Lots of good answers here, but I can provide an overview with less text.
## Wormgates are easy.
They require infrastructure. Think of this as your railroads: high infrastructure cost, limited access points, but cheaper transport cost. They would be an industrial staple. You have to get someone to the destination and build the gate on the other side, but once you build it, you can send ships without having to build an expensive wormdrive or warpdrive into them.
## Wormdrives vs. warpdrives
You have to build limitations into them. This is part of your job as a fiction writer. What are their energy requirements? What are their limitations in respect to obstacles? How far out of a gravity well do you have to be to use them safely? What is the spin-up time for a wormdrive, and how many jumps do you get on a tank of gas, and what is the range of the jumps? How often do you have to stop for fuel for a warpdrive, and how easy is it to get?
The relative efficiencies will tell you if you have a situation where a ship might have both. Maybe a small warp drive for moving around a solar system, and a jump drive to get between stars, or a large warp drive for exploring deep space (or a nebula), but a smaller jump drive with a really long spin-up time that's just designed to get you there and back. Maybe bigger versions of both, but very little room for cargo or crew.
## Story over realism
Decide what the balance is for the story you want to tell, what limitations might provide the best dramatic points for your story, and run with it.
[Answer]
# Energy usage
To send smaller ships, the Energy needed can be easily provided by the ship's own power plant. But as the ship size increases, so does the power draw, but exponential. A ship twice the size needs quadruple (or more) power output for the same jump. Power plants however scale linearly, so that there is a maximum ship size that can be used with its own worm engine.
The maximum worm engine size for a given reactor is what gives us the upper line of military craft, which encompasses anything from a small destroyer to a carrier. With some ingenuity, the carriers might even dock their escorts to take them along in a jump, using the oversized power supply of the docked ships to give the needed power to take them along with the main ship's worm drive.
However, this size sweet spot of where your ship starts to suffer from taking up too much space for drive and engine means that cargo ships would have significantly impaired cargo capacity. To avoid that and have maximum cargo, large vessels use static, external drive generators, the worm gates. Because a gate only moves the ships, not itself, it can be almost entirely generators to send the massive cargo ships through space.
# minimum size requirements
A stable worm jump requires a minimum ship size that is above the average interplanetary shuttle size. As a result, small shuttle routes rely on more compact but slower warp engines to get to work gates that catapult the ship forward and take the last leg by warp again.
# Worm drives and gates are disturbed by gravity fields
To open the wormhole with a worm drive or gate requires fine calibration. Gravity fields need to be very consistent and barely changing to allow the proper calculations to be done in a manageable time, limiting their use to the outer periphery of solar systems. However, their speed advance over mere warp means that most ships with warp use gates for long legs, cutting their travel times from months to days.
[Answer]
**Safety**
Other answers have touched on this but I thought it bore some further discussion: the main reason you still have warp drives at all is they they are a 100% safe means of travel. "Space weather" (flares, supernovas, black hole collisions, etc) can cause all kinds of havoc on interstellar travel, especially [I am speculating] on worm holes.
Worm hole calculation must be very difficult. You would presumably be mapping out gravitational fields between A and B but those fields are constantly shifting and you can never be sure what they are right now (you can only base it on what you see right now, which is, thanks to the speed of light across long distances, very dated information).
If you encounter something in your warp drive, your errors will be very minimal as you only need to calculate millisecond by millisecond based on local conditions. Errors on worm drives could surely be rather enormous. On the other hand, wormhole travel should be instantaneous -- you are linking A directly to B so you simply fly through and you're there. So very long distance exploratory travel probably uses worm drives to get to the general area (likely with some forward probes for safety) and then warp drives for the fine details.
Worm gates presumably make wormhole travel safe and predictable, perhaps acting similar to a lightning rod and "attracting" the destination wormhole to that gate, in addition to allowing plain vanilla ships (such as cargo haulers) to make the trip without needing their own special drives at all. Although maybe once in a while, weather conditions are sufficient to cause a wormhole to miss its intended gate and either open to some random location or end up at the wrong gate... (This probably presents minimal risk, since they could open the wormhole at the source, send through standard radio queries to make sure it has connected correctly, then green light the traffic. If conditions have gotten off enough that the gates are not connecting, then they may have to disable them temporarily while they figure out what has changed and recalculate.)
[Answer]
It all comes down to money - abstracted, in this case, as energy cost.
A wormgate, while a permanent portal to another location, will transport anything any everything through it, like a regular door. That means you can't have one in your living room and one at Grandma's, because Grandma lives near the beach and you live upstate - the pressure difference would mean there would be gale-force winds pouring through the gate at all times. The safest place to put a gate is in space. Vacuum is vacuum, give or take, so you won't be paying the energy cost of transporting more than a bit of space dust. Wormgates are *highways*, designed for high traffic flow of otherwise normal vehicles, between well-known locations. Gates need to be linked, because each gate supports its end of the wormhole - only a stabilizing structure pouring energy in keeps the wormhole stable.
A wormdrive takes the same computing power, energy, and resources as a gate, but since the wormhole is single-use, it doesn't need a gate on both sides to maintain it. It's more like crawling through a fabric tunnel - you lift the bit you're in, and the rest stays closed. Ships with wormdrives are supertankers, giant cargo ships, military ships, and freight trains - best used to transport huge amounts of material or people to locations that may not have wormgates, or in such quantities that the sheer mass would would clog up a worm gate for a long time. The military uses them because, frankly, the military doesn't care how much it costs to drop a frigate behind enemy lines; big shipping companies use them because they can transport the wealth of a large country from A to B, and profits from the trip dwarf the costs. A family or exploration team would balk at the exorbitant energy cost.
The warp drive is akin your average truck, family car, or ATV. It's not as efficient as a wormdrive, but it's a whole lot cheaper when you're only hauling a handful of people. It has a low energy cost, it can be turned off when not in use, and it's reliable, especially out where it's not cost effective to set up gates. If you don't live near a big population hub or tourist destination that would have a gate, and you don't have the budget of a small country to run a wormdrive, your best bet is the slower, clunkier, noisier, but vastly cheaper warp drive.
[Answer]
You can fix anything with economics. A technologically inferior method is likely to persist if it cheap enough compared to the alternatives.
Also:
A wormdrive requires the exact "coordinates" of its destination to be known. This might be more involved than mere position. Gravitational influences at all points along the route, because they bend spacetime? Even tiny errors become significant when propagated over hundreds of lightyears.
So you need warpdrives for exploration and surveying / route maintenance. You also need minimal ones on every ship for getting out of trouble if the wormdrive delivers you a lightyear away from your intended destination.
As for wormgates, they need expensive infrastructure at both ends. You can't go anywhere new. Also you can't economically justify them on routes that don't see a lot of traffic. Or you can make up other reasons. But they might just be the Airbus 380 of the interstellar transport market: too expensive in all but a few special cases.
[Answer]
>
> My question is can wormdrives, wormgates and waprdrives in this scenario exist without making any of them redundant/obsolete?
>
>
>
Yes, because each of them has different use cases, requirements and limitations.
## Warpdrive
A warpdrive-powered ship is ideal for short distances, from in-system travel to nearby star systems. It's a slower trip but much simpler and more maneuverable. Just point your ship in the general direction you want to go (within a few arcseconds perhaps) and go to warp. If your aim is off you can drop to normal space, reorient and then go back to warp. No clever, time-consuming calculations required, and basically anyone can be trained to fly the ship in a couple of weeks.
The other advantage is in power usage. A warp bubble takes a fair amount of power to establish, and the total power usage over the trip may be a little higher than a wormdrive, but the peak power usage is significantly lower than either of the other two. That means you can save a lot on the power system.
The main downside of course is that warp is (comparatively) slow. It's going to take days or weeks to reach your destination, but for cargo or low-priority passenger transfers that's unlikely to be important.
## Wormdrive
These drives are the best option for fast travel between arbitrary locations. Punch the destination coordinates into the navigation computer, give it half an hour to calculate the exact parameters of the required quantum field geometry, punch a hole in the fabric of reality and next thing you know you're on approach to Spica III in time for that big conference. Assuming the navigation computer is functioning perfectly and your sensors have correctly locked the navigation references.
The main downside is the massive amount of power required to actually open the wormhole and hold it in place while you traverse it. It's a lot of power in a short period of time, which means you need a hefty power system. You don't have to generate the power all at once, you have time while the navcomp is running the field computations, but you'll need some really big accumulator banks to hold the power ready for breakthrough.
The big downside, apart from all that waiting for things to charge and such, is that the power requirements increase exponentially with range. There's a sweet spot beyond which it's cheaper to make multiple jumps, and most wormdrive ships won't have power systems capable of going much further than that. Still faster to travel than warpdrive, but it might take days to travel to distant parts of the Empire.
## Wormgate
As fixed structures gates can have much larger power generation and storage than ships could reasonably carry. And since both ends of the wormhole are held open by a gate mechanism the power cost of both establishing and maintaining the wormhole is greatly reduced. This means that gates can be used to travel much greater distances than wormdrives, with the added bonus that ships don't require special drives to traverse the wormhole. And because the positions of the other gates are known ahead of time the calculations required to generate the wormhole are much simplified.
The advantages here are pretty obvious. Lots of options for long-distance travel that other drives can't match, and you can funnel a fair amount of cargo through the network fairly quickly. So of course the downsides are kind of huge. The further the distance between gates the shorter the wormhole's duration, but that's not a significant issue unless you're trying to get a whole fleet from one side of the gate network to the other.
The main downside is the recharge time. Each of the gates in a connection will be discharged after the wormhole collapses and will need some time to recharge before it can open another wormhole. Depending on the generation capacity this might be an hour or more, and the gate is useless during this period. Attempts to connect to the gate during this time will fail, with the originating gate using up a portion of its stored power in the attempt. If you have three or more gates to work with you can keep a target gate out of action basically indefinitely. Great for system interdiction, if you're that way inclined.
[Answer]
>
> can wormdrives, wormgates and warpdrives in this scenario exist without making any of them obsolete?
>
>
>
Cheap, fast, no infrastructure required. Pick 2 out of 3.
Gates probably require a large upfront cost but transit is very cheap per ship. Probably gates are not alone in the system - they form an interstellar highway system allowing to fast travel for vast quantity of good and people. Most people/companies (depending on how affordable spacecraft is) on core systems don't own FTL vessel. Why would they if they can reach everything (outside of backwater systems) with traditional ones and gates? It's like owning 4x4 when you live in a city.
Wormdrives form a second tier system. They require no upfront cost and are fast. But cost per-ship is probably much higher so likely they are used for large ships (economy of scale) or for time-sensitive cargo (military/government use etc.). This may be how many people travel off the core systems (depending on price).
Warpdrive is a tertiary system. Good for cheapest routes allowing connecting systems to which it would be uneconomical to maintain other routes or as second tier system for less time-sensitive cargo. If you ship bulk goods they will be shiped by warpdrive. If you have a more price sensitive passengers they will pick warpdrive.
>
> How could I justify why wormgates need a destination gate? And are there any other redundancies or more efficient ways to use this tech I have overlooked?
>
>
>
Power requirement increases superlinear with distance. However if you link two gates you can lower energy consumption. However they need to have a pair to complete another side of connection.
Also the second gate signifies where the exit will be. Since gates are in busy systems you need to have a place where ships can queue and avoid traffic. You probably have an equivalent of Bravo airspace.
[Answer]
Well, from a purely technical perspective, jumpgates have an obvious use a main axes for commerce and migration.
First, existence of two anchor points, an entrance and an exit, means more stability and thus the ability to maintain the wormhole over greater distances. That gate networks are well known makes it easier to manage them and avoid accidents like from different origins trying to jump at the same coordinates at the same time.
Second, every vehicle is a compromise : for a given size you want to put the most stuff inside yet have it use a little energy as possible. Wormdrives take space, cost to maintain an draw power. All of that can be allocated to, say, more cargo or passenger space! Makes Jumpgates more cost-effective!
Their downside, however, is that they still cost an arm and a leg to make! And even more to maintain! Obviously you're not gonna use them to connect every planet in your empire, you're keeping their use for the more-traveled paths, where they're the most cost-effective.
Wormdrives however have the ability to jump from wherever their current location is, as long as they know where they're going and that it's not too far for their drives. Even if it is, they can leapfrog their way. This will make them very effective outside the gate network and extremely useful when required to travel outside of said networks, like a hidden military base that's really accessible only if you know its exact coordinates.
Warpdrives, at first glance, may seem inferior. But, in truth, they're ubiquous. Sure, they're the slowest method and wormdrives also give freedom of navigation, but they're cheap! They're the oldest, mature tech of the three. Sure, it ain't shiny, but they've become very fuel efficient, they have plenty to failsafes against any possibility of crashing (at ftl speeds you can't rely on the pilot's reflexes after all) and they don't require any precise calibrations based on ship's mass like wormdrives. Plus, unlike wormdrives, which are highly regulated and whose tech is kept a state secret, anyone can learn to make and maintain their warpdrive!
From a political perspective, the freedom of wormdrives is risky to governments as that makes them harder to control. Sure, warpdrives gives a similar freedom, but at least those are slower and much more easily detected! Obviously smugglers and other people whose activities run afoul of the law would love to get their hands on them, but they are highly regulated and difficult to obtain.
EDIT:
Didn't notice the question changed a bit. About exit wormgates. It's well known they're necessary, for stability and all that. But, funny thing is, it is possible to use wormgates without one! People suspect it, but with governments keeping wormdrive tech secret, no one really knows for sure and no gate was ever used that way, that we know of... But even if they knew, wormgates have been designed to work in pairs now. Trying to open a wormhole to a place without an exit wormgate to share the power load? At best nothing happens, at worst your ship ends up God knows where...
[Answer]
[@JohnO](https://worldbuilding.stackexchange.com/a/229517/83464) has the right start, but there is a way to make all three technologies simultaneously viable and important.
Here are the principles you need:
1. To make a wormhole by drive or gate, someone needs to have gotten to both of the ends of the wormhole and spacetime mapped them in sufficient detail sufficiently recently to make a wormhole.
2. Wormholes are unstable (as you mention in the question) and can only last a few minutes.
3. There isn't FTL communication other than through wormholes or warp mail (you stick a message on a ship that goes to warp).
4. All such drives are non-negligibly expensive.
Given this, here is what we end up with:
1. **Wormgates** are for high traffic routes and for small ships. Wormgates are permanent stations that are constantly doing spacetime mapping of their area and opening wormholes to other wormgates to transmit that data so that the network stays in sync. The core gate network would be small due to the quadratic number of upkeep wormholes needed to maintain it (each gate needs to stay up to date with each other gate); the rest of the network would be connected by a hub and spoke model (much like modern airports). Not all ships have native warp/worm capabilities and those that don't need to rely on the gate network for long-distance transit and may need to use multiple gates to get places. In modern terms, this is the equivalent of flying commercial.
2. **Wormdrives** are for big ships traversing lower traffic routes to settled destinations. If you want to get to a wormgate without needing to go through multiple layovers and you have a wormdrive, you can just buy a spacetime mapping of your destination from the local wormgate (which they sell for much cheaper than passage itself). Note that you can typically only wormdrive to places in the gate network, unless you have the assistance of warpdrive shps (see below!). In modern terms, this is the equivalent to chartering a private plane.
3. **Warpdrives** are needed when there aren't gates maintaining an FTL link between the places you want to go. Someone has to get between A and B sufficiently fast enough to have valid mappings of both A and B and be able to wormdrive between them. Thus, a warpdrive can get you to arbitrary places not on the gate network given enough time. In modern terms, this is the equivalent of driving.
4. **Combos:** Warpdrives are also essential for expanding the gate network or allowing temporary routes between places. There is going to be some max distance on this, depending on how fast mapping data goes stale and how fast warpdrives are, but that formula gives you a distance of X lightyears that you can send a warpdrive + wormdrive scoutship that can then wormdrive back with mapping data and allow for a temporary wormhole transit between two places. That temporary wormhole can then be used by the same scoutship to go back and forth between those two spots to keep up to date mapping data for a longer period, which could eventually allow construction of a new wormgate.
[Answer]
Babylon 5 does this - their jumpgates are fixed systems that allow ships with no/limited hyperspace capability to enter hyperspace, and act as part of the navigation beacon system. Warships and some other ships have organic jump capabilities. 2 factions have their own jump tech (the Shadows simply phase in and out of it, and the thirdspace aliens have their own hyperspace-like-dimention).
Organic jump is "heavy", power and cost expensive, and you don't really want to throw it on say a grain freighter, but a destroyer might find it tactically useful and worth the cost.
So
>
> Warpdrives don't require destination coordinates. They can be activated and deactivated at any time to move continuously through space. But they are the slowest of the three, and are easily tracked and detected.
>
>
>
While slow, you can use this for *initially* plotting out space since you can go anywhere and get back. These would be useful in exploration and expeditionary ships, or for short range tactical jumps. These would also map out space for the other 2 technologies, so you could have detailed spacial maps for jump calculations.
>
> Wormdrives require precise destination coordinates. The Wormdrive mounted on your ship creates a temporary traversable wormhole that starts in front of you and ends at the destination coordinates.
>
>
>
These would be the 'classic' jump drives - mounted on warships and ships that need to go to mapped locations that are off the main spaceways. You can jump anywhere mapped, and out. These would be less flexible than your warpdrives, but more so than fixed gates
>
> Wormgates are two wormdrives linked end to end. You need one ship at the start of the wormhole and another one at the end.
>
>
>
These would be what you have on the principal systems of an interstellar polity. Since they're fixed, mass, cost and power are less important, and they allow ships with no jump drive to travel between points. They'd allow simpler low cost ships jump travel and as such be the backbone of the civilian and peace time military transportation network.
] |
[Question]
[
I have a character who engages combat finishing with in-armour duel that pushes her to the limit. After it is over she is so exhausted (and probably dehydrated) that she faints.
Assuming:
1. she is not severely wounded and there is no underlying health condition, just exhaustation from combat
2. there are people who can help immediately
Would it be realistic to faint?
Would she regain consciousness pretty much instantly (within minute or two)?
Or would it take some time?
[Answer]
Let's first establish the differences between some of the reasons your character might have passed out.
* **Exhaustion**: Working hard doesn't really make you lose consciousness on its own, but depending on other factors it can contribute to one of the others reasons you might pass out. A physically fit person who is properly hydrated and not overheated can exercise until there is just nothing left to keep going on and still remain conscious. So saying someone fainted from exhaustion is generally not accurate.
* **Shock:** This is your body's natural response to severe trauma, this is where your body restricts blood flow to your extremities to keep you from bleeding out. This can include cutting off blood flow to the brain which can lead to unconsciousness. What you've described could happen from shock, but since your character is unhurt, then this is an unlikely reason to pass out.
* **Asphyxiation:** This is what happens when you don't get enough oxygen to your brain for any reason. Because your character won the duel, it is safe to assume that she did not pass out due to lack of oxygen. While a plate armor helmet or generally bad health can restrict breathing enough to cause you to pass out, everything leading up to this would include gradually increasing muscle weakness which would have almost certainly prevented her from winning her fight. Basically, by the time your brain gives up, so have all your other appendages.
* **Heat exhaustion:** This is a momentary loss of consciousness that forces your body to stop exerting itself when overheated. Heat exhaustion generally has no long term negative side-effects. This is your body's natural way of protecting itself from overheating, and your most likely culprit. It is a common problem, even for seasoned athletes and heavy laborers. It often comes on quite suddenly rather than wearing down your physical capabilities like asphyxiation would, and does not require something being "wrong" with you like shock would. Heat Exhaustion is an especially a common problem when fighting in plate armor.
* **Heat stroke:** This is what happens when you become so overheated that you sustain brain damage. This is a true medical emergency which normally results in permanent neurological damage, coma, and/or death. Based on the context of the OP, I will assume this is not the case.
* **Hyperventilation:** This is another distinct possibility. When some athletes work out too hard and then suddenly stop, they are left breathing very hard to catch up to where their blood CO2 levels should be. In some cases, this will overcompensate and over oxygenate the blood causing lightheadedness, numbness, tingling, anxiety, and in severe cases even fainting. This is one of the reasons why athletes are encouraged to do cool-down exercises when thy are done so that they can slowly bring their breathing and heart-rate back to their resting state. This could fit your situation well because it is something that distinctly happens when you STOP exerting yourself. That said, it is not nearly as common as heat-exhaustion, mostly happens to novice athletes or those with underlying conditions when it does happen, and would likely be prevented by the restrictive nature of being in full armor. Just because your helmet, coiter, and breastplate restrict breathing as much as they do, no amount of huffing and puffing would get your blood over saturated. So, I suspect this could only happen if your hero has armor she can easily get off of her after the fight (So might happen in 10th century mail armor, but not 13th century plate armor).
**Given the factors at play, I will assume your hero passed out from Heat exhaustion.**
Secondly, How long "unconsciousness" lasts can be very misleading in this case since a full loss of consciousness is actually very rare. Rather you go through a series of degraded and recovering states of consciousness. Below is the the general timeline of what these various degrees of consciousness should look like from both the internal and external perspective.
## What it is like from a first person perspective
As you start to reach the critical stage of heat exhaustion, the first symptom is that noises begin to sound muffled and more distant. Some kind of white noise like a ringing in your ear or the echo of being under water is also common. Then your vision begins to "slide". This is where your eye stop properly tracking what you are looking at and vision becomes distorted and blurred and it looks like your field of view starts to slide around even though you think you are still looking forward. All of this can happen very quickly or over the course of a 1-2 minutes. In the latter case, it is normally that you feel yourself going into heat exhaustion, but keep pushing yourself anyway.
Time also becomes hard to track, it is hard to say if time feels sped up or slowed down, but it certainly does not feel normal.
Then you blackout. You normally still have some level of conscious awareness of yourself when this happens, but you can no longer see, hear, feel, etc. in any normal capacity or control your body at all. It is like suddenly being in a dark empty room. You are still conscious in the since that you are aware of having a state of being, even though your mind is cut off from your body, it is also common to experience a general sense that you are falling. Once you go down you immediately start to feel better. Vision and hearing start to come back within moments. You still feel overheated and exhausted, but a normal type of overheated and exhausted. People around you will probably look really panicked and insist you stay down, your cognitive abilities will be diminished but it may take what feels like a good 10 seconds or so for your brain to fully grasp that you are even having trouble thinking straight. It will feel like 1-2 minutes before you truly feel normal again, but getting up and moving around may make you dizzy. So while loss of consciousness was very momentary, a full enough recovery to get up and walk away may take 5-10 minutes. It will probably take 20-30 minutes before you feel ready to do any physically demanding tasks again.
## What it is like from a third person perspective
From a third person perspective, the affected person usually seems very confused at first. They might look at you like they acknowledge you, but don't understand what you are saying and don't remember what it is they are supposed to be doing. Then loss of body control seems spontaneous. Their whole body goes limp all at once and they fall over. In every case I've seen, the actual loss of consciousness (where they are completely unresponsive) has lasted between about 5-15 seconds. From there they can often open their eyes and start looking around, and maybe mumble some very difficult to understand words. Often it's something to the effect of "I'm fine" even though they clearly are not.
Within 1-2 minutes they should be able to sit up on their own and have a mostly normal conversation, but they can not keep their balance if they try to walk. After about 5-10 minutes they can normally get up and walk around. Although their body seems to be functioning fully at this point they may not seem fully themselves until about that 30 minute mark.
[Answer]
If a person loses consciousness due to overheating or dehydration (heat exhaustion or heat stroke), it's a medical emergency; there's a possibility she'll *die* without being externally cooled and getting fluids -- and she could choke to death or drown if someone tries to administer fluids by mouth while she's unconscious.
Heat exhaustion need not proceed to loss of consciousness to be serious, but if she's conscious, it's probably possible for her to cooperate enough to at least get her armor and padding off, at which point dampening exposed skin and remaining clothing with cool water will start the process of safely cooling her. There are well documented procedures to follow to prevent and treat heat exhaustion (where I work, we get a reminder of this in our safety newsletters about this time every year); they all revolve around hydration and avoiding excessive exertion in excessive heat.
[Answer]
Fainting [usually happens when blood flow to the brain isn't adequate for a short period, this can happen due to extreme heat, dehydration, exhaustion or even due to illness](https://consumer.healthday.com/encyclopedia/first-aid-and-emergencies-20/emergencies-and-first-aid-news-227/fainting-and-loss-of-consciousness-644511.html#:%7E:text=Fainting%20often%20results%20when%20blood,occur%20after%20taking%20certain%20medications.). Your character is wearing armor, exhausted and possibly dehydrated so she can easily check out 3 of those, 4 if she was already a bit sick before combat. If she's not actually dehydrated and the main cause was a mix of mostly the heat and exhaustion from the battle, then if my personal experience is anything to go by she shouldn't stay out for too long (probably from a couple seconds to not much more than a minute), and the best to do is put her leaned down in the shade and remove excessive gear to help dissipate the heat. Also if possible don't let her fall on the floor and hit her head, or she might experience [convulsive syncope](https://orthoneuro.com/syncope-what-really-happened-when-you-fainted/) (fainting followed by a certain amount of jerking, can be mistaken with a seizure. The individual regains consciousness shortly after and usually fully recovers without problems, I can tell you it's not an enjoyable experience, but it can happen without any noticeable damage to the brain) or something worse if she does hit her head or neck on something.
[Answer]
**Don't underestimate severe exhaustion (like several days/months without or with really minimal sleep). The person might be able to function for a short while in a high-pressure situation, but the result will be he will just fall asleep at the first sign of ending.**
I have a very heavy case of sleep apnea, which causes me to choke when I sleep (treated with a pump that forces air to my mouth/nose and keeps my breathing tubes inflated with overpressure called CPAP) and **one of the other reasons you can pass out is simple extreme exhaustion.**
Just before I signed myself into a sleep laboratory/clinic to get treated I slept about 30 minutes a night in 30-second intervals for 8 - 12 hours (the rest I was unconsciously choking).
In the end I was literally passing out every time I just stopped to sit or stand. I couldn't do anything, couldn't think properly and kept passing out. **If there was nothing pressing or after doing anything strenuous and registering the need for alertness was over, I just passed out.**
The onset was usually preceded by all of the sounds slowly muting - like coming from far away or another room, my eyes closing on itself and becoming so extremely heavy and I just retreated to my inner world and my thoughts slowed down to a trickle, only for a sudden jarring sensation as everything becomes back into focus and you realize that you were sleeping and don't know how much time passed or what happened.
My oxygen levels got as low as 62% during the night (the doctor at the clinic was really surprised I was even conscious)
I couldn't think, couldn't concentrate (I was like a goldfish, constantly forgetting what I was doing or needed to do).
The first time I got the CPAP (it was just a loaner from the doctor to see if it would work for me) I cried after I woke up. I slept 14 hours and only choked about 6 times in an hour instead of every 30 seconds.
Only after I got some real sleep I was able to realize my own situation again. I stopped cleaning my home, stopped cooking, or going shopping since I couldn't remember what I needed to buy. I was barely able to get dinner from fast-food restaurants since it was all I could do to order, pay and get it home to eat and then pass out in a chair. I was sometimes able to fill a washing machine and clean some clothes. I was just too exhausted to do anything, really.
[Answer]
When I broke my legs I passed out from the pain for like a few seconds to 3 minutes... but it happened multiple times (within a few hours), I also once run to almost exhaustion and collapsed on the streets and it took about 2 hours for the dizziness and nausea to pass. I learned that when doing cardio you only feel tired after you stop out of boredom, so one might run or fight to exhaustion without even realizing it, because I felt incredibly good while running and the exact moment I stopped I dropped on the ground struggling to breathe, I also felt the blood leaving my brain but that might just of been a strange sensation. Maybe the hype and adrenaline of fighting is similar to the hormones one gets when doing cardio.
I have never fought but combat should be a mixture of pain and tiredness so it may help.
But I think heat is the most dangerous thing, broken bones and bruises can kill with thrombosis but the chance of survival is high enough, exhaustion also isn't too dangerous.
Probably it depends on the type of armor, plate armor on a sunny day in a continental climate might be a big deal.
[Answer]
I'd like to add another possible cause that fits your scenario and gives a longer and more flexible window: **Hypoglycemia** (low blood sugar). As I diabetic, I am familiar with this condition as treating the high blood sugar caused by diabetes can often cause this as a side effect.
In my experience, the effects of this are varied, and can cause a blackout. Usually the effect is tiredness and confusion, but still a level of consciousness, but there has been at least one time where I did eventually blackout. Thankfully I woke up later, about a half hour later. I think I didn't just blackout, I also fell asleep. I vaguely remember walking around not knowing what was happening for a few minutes, and then nothing until I woke up on a bench. Apparently I had had enough consciousness to lie down, but not any more.
It seems possible that [Exercise-induced hyperinsulinemic hypoglycemia](https://rarediseases.info.nih.gov/diseases/9932/exercise-induced-hyperinsulinemic-hypoglycemia/cases/42576) could be a possibility, especially if your character had not had a particularly nutritious diet recently. If a savvy medic recognized the condition, they could treat it easily with just some fruit juice, but if left untreated it could take a while to recover from, but probably not more than a few hours.
[Answer]
I have seen this happen. (technically, it wasn't combat)
When I was in college, I lived in house with a large number of housemates. One afternoon, several of us were watching TV in the living room and one of our housemates staggered into the house, wobbled a little, and collapsed.
Luckily, we had a few medical school students in the house (the university has a world-renowned medical school), so they did their thing, but after a minute or two, they said she was still unresponsive (their word, so presumably in the medical sense) and we needed to get her to the ER. I helped transport her there and stayed until her boyfriend could arrive and take over, so I can tell you what I saw.
She had no issues breathing, but wouldn't respond to stimuli. Her eyes were open, but the lids were droopy and the eyes themselves were unfocused and swimming and wouldn't track an object. She didn't respond at all to her name, loud noises, shaking her hand, anything.
The medical students declared her safe to move, so we picked her up between two of us and she was completely limp. Someone had to hold her head to keep it from lolling because it was also completely limp. We were able to get her into a car and down to the ER. It had been about 10 minutes since she collapsed.
Maneuvering her into a wheelchair at the ER, her eyes were starting to track and she moaned a couple of times. The nurses got her into a bed and her boyfriend got there about 10 minutes later. She gave him the slightest smile when he arrived, so at that point she was at least starting to recognize people. I left at that point and we found out from her boyfriend later that she got a glucose drip and perked up within a half hour or so. The hospital wouldn't discharge her for a couple hours after that, just in case.
It turns out she was a dancer and we found out afterward from her boyfriend that she had been training for her MFA recital about 12-14 hours a day for the last two weeks straight. He said he had been telling her to eat more and sleep more, but she refused.
This only gives you one data point, but 1. there was no wound or underlying health condition (except for maybe a little undernourished and short on sleep) and 2. there were people who could help immediately. The final timeline was unresponsive for 10-15 minutes, minimally responsive for another 10-15 minutes, fully responsive after another 30 minutes on a glucose IV.
[Answer]
**Vagal (Vasovagal) Response**
Depending on what effect you want to achieve, after an intensive effort people can get a vagal response that can make people faint just **for a few seconds** maximum. Most of the time you'll just fall to the ground due to your legs feeling really weak.
[Answer]
# As long as you want
There are a number of conditions that could cause someone to faint. Maybe your character is simply exhausted and takes a short cat nap. On the other extreme, your character could have heat stroke, which is a serious medical condition that sometimes proves fatal. Here's a [good overview of heat stroke](https://www.aafp.org/afp/2005/0601/p2133.html). How long could someone be unconscious from heat stroke? [This case study](https://pubmed.ncbi.nlm.nih.gov/15127143/) highlights a patient who lapsed into a coma: "The patient regained consciousness and was discharged from our intensive care unit after 16 days."
So you can use real world science to justify any length of unconciousness.
] |
[Question]
[
When the giant aliens came lumbering out of the interdimensional fissure, we fought back, building giant robots of our own... which promptly collapsed onto themselves and were unable to move because of (among other things) the square-cube law and lack of materials with adequate tensile strength to stop the damn thing crumpling under its own weight, inertia and torque requirements. We took a step back, mourned our losses, then started using nukes and kinetic missiles on the aliens like sensible people.
A metallurgist studying a crystal of unobtanium diphlebotinide, discovered its unusual property of forming perfectly (down to the near-atomic scale) cylindrical crystals. He found that if he ground the crystal to be within a few nanometres of being exactly 42 times longer in axis than diameter, and waved his hands over it while fumbling his coffee cup, the crystal settled into a phase with (as best they could determine) infinite tensile, compression and shear strength; it is to all intents and purposes indestructible. I believe physically-necessary consequences are an infinite (or at least speed-of-light) speed of sound, and zero coefficient of friction. They subsequently found that if they 'cast' the crystal already having a perfectly cylindrical hole perpendicular to the axis and one-forty-twoth the diameter of the parent cylinder, then it would still set with the hole, allowing them to join crystals together into larger structures.
I think this (long thin spars with the means to fix pinions to transfer force between them) is all you need to use this new material in construction, including superstructures for giant robots. The zero-friction aspect also makes them excellent axles and bearing plates, and I can imagine lots of smart people immediately setting to designing all sorts of complex machines using them (reminds me of childhood construction toys!). But I'm hoping that the nature of the material means they can't be so easily used to create 'armour': you can't weave them or construct any sort of solid plate, for instance, although it could be used as reinforcement *behind* armour or pressurised enclosures.
Is this material alone enough to 'solve' the standard problems with giant mecha, namely collapsing under their own weight because their legs can't be strong enough, not being able to move their limbs because we can't produce motors with enough torque, and so forth? If not, what problems would remain to overcome?
Let's leave aside the question of *why* you would choose to attack a giant alien with a giant robot in preference to a nuke even if you *could* build one. I'm not asking for a mecha that's an appropriate combat weapon, or even humanoid; more like something to compete on a giant version of [Robot Wars](https://en.wikipedia.org/wiki/Robot_Wars_(TV_series)).
[Answer]
>
> Is this material alone enough to 'solve' the standard problems with giant mecha, namely collapsing under their own weight because their legs can't be strong enough, not being able to move their limbs because we can't produce motors with enough torque, and so forth? If not, what problems would remain to overcome?
>
>
>
So, the short answer is that this would make it SOMEWHAT less difficult to build a humanoid mecha, but Adamantium would do nothing at all about the REAL Mecha Problem, which is that anything you can build a giant humanoid robot to do, a robot that is NOT humanoid will do better.
Adamantium also isn't going to solve power problems. It will mitigate them by allowing the structure of your mecha to be lighter than it would be, and thus require LESS power in order to move it around, but you're still stuck with electric motors or hydraulics to actually move those limbs, and it's just not a very effective means of locomotion.
[Answer]
**No. Wrong strength.**
from OP:
>
> stop the damn thing crumpling under its own weight
>
>
>
Your new stuff has infinite tensile strength.
>
> the crystal settled into a phase with (as best they could determine)
> infinite tensile strength.
>
>
>
But to stop something crumpling under its own weight you need better compressive strength! Tensile strength keeps stuff from being pulled apart.
<https://en.wikipedia.org/wiki/Ultimate_tensile_strength>
>
> Two vises apply tension to a specimen by pulling at it, stretching the
> specimen until it fractures. The maximum stress it withstands before
> fracturing is its ultimate tensile strength. Ultimate tensile strength
> (UTS), often shortened to tensile strength (TS), ultimate strength, or
> Ftu within equations,[1][2][3] is the capacity of a material or
> structure to withstand loads tending to elongate, *as opposed to
> compressive strength, which withstands loads tending to reduce size*.
> In other words, tensile strength resists tension (being pulled apart),
> whereas compressive strength resists compression (being pushed
> together).
>
>
>
Emphasis mine.
Maybe your engineer does not have English as his first language? I hope you did not build a whole mecha out of this new stuff before you figured it out.
Should you, like me, be an engineering aficiondo approaching from a position of ignorance, I recommend [The New Science of Strong Materials](https://rads.stackoverflow.com/amzn/click/com/0691180989). Easy to follow and well written.
[Answer]
One other problem is [ground pressure](https://en.wikipedia.org/wiki/Ground_pressure).
The maximum bearing capacity of *the ground* is unaffected, and remains relatively low.
For reference, bearing capacity of stiff clay might be [300 kPa](https://www.geotechdata.info/parameter/bearing-capacity.html), or about 30 metric tons per square meter. (Until everything turns to mud at least!)
This is already a problem for e.g. tanks.
For a given loadout, a tracked or wheeled vehicle would (almost) always end up with an easier time dealing with bearing capacity limitations than a mecha. A mecha's walk cycle would exert significantly higher peak loads then a wheeled or tracked vehicle, and would likely exert significantly higher horizontal forces too. Running would be even worse.
Some of this would be alleviated if the vehicle was lighter, and yes, adamantium would help with structural weight. But it wouldn't help with the weight of everything else (drivechain, controls, pilot, weapons, etc.). And meanwhile adamantium would help with structural weight of the competition (tanks, etc) also.
[Answer]
Yes, but it comes with more problems than it solves and you don't need it.
Stronger and lighter materials enable you to build larger structures, more effecient engines and power transmission etc etc so bigger robots.
Infinitely strong materials start to break physics. Don't go there
But you really only need a robot as large as the alien monster right? and that's made of flesh and bone. Bone has evolved over millions of years and has about the same strength to weight ratio as steel/titanium/wood etc.
So you can totally make a giant robot on the same scale as large animals, say dinosaurs, without stretching crediblity Maybe you can push it a bit with carbon fiber or metal foams
[Answer]
Many problems.
First, something that is infinitely (or nearly so) incompressible will be desastrous towards non-soft materials it comes in contact with, and desastrous when receiving an impulse from somewhere (alien punching the mecha?). Remember that your mecha isn't just "hull". There is something inside, too. Either a human, or a computer, or something the like. Gyroscopes, sensors, hydraulic tubes, whatever.
Every impact from the outside (including the effect of Newton's third law when the mecha walks!) will be transmitted one-to-one. So whatever is inside will meet an unpleasant end very quickly ([related](https://worldbuilding.stackexchange.com/a/54340/3066)).
Second, wind. You are able to build a huge thing that has comparatively little weight. Guess what happens when the wind blows.
Third, what's the purpose of a mecha? Well, it's huge and it has huge physical force so it can deliver a big punch. But your mecha doesn't have mega force. Your adamantium makes its exterior indestructible, alright. But that doesn't mean its servo motors are any stronger. In fact, getting over air resistance alone may be a serious problem for such a huge thing, unless slow-mo fights are an option. Also, delivering a big punch (which means impulse) requires a certain weight, too. So, at least the mecha's fists **must** be heavy, or the whole thing defeats the purpose.
As an analogy, no matter how hard I throw cotton balls at you, the amount of injuries that you will have is rather limited.
Then of course, building something huge from nanutubes is a real challenge. That'll take a few years to build one mecha.
Also, a material with infinite-whatever is not suitable for everything. You need flexible materials to build something that moves. If nothing else, you will need e.g. wires or tubes for electricity or hydraulic fluid. If these are not made of super indestructible material, the first paragraph applies. If they *are* made of super indestructible material, they're not flexible, and the mecha cannot move.
Does your world have any such thing as dust or sand? If yes, you should seriously hope that none of it gets into some joint or gear. In the real world, this is to some extent tolerable because both the sand and the gear experience a bit of abrasion, and the lubricant does the rest. For a perfectly rigid, indestructible thing, the only option is to grind whatever comes in between down to, well, basically a molecular level. Which may be a challenge.
Also, it's questionable whether the approach of attacking a huge thing with a huge mecha is intelligent at all. You said "leave this out", but it's really something you should consider.
I have no difficulties killing a dog with little or no injuries, while defending against a swarm of bees is much harder. Defending against roughly cell-sized parasites (think malaria, amoebae) or bacteria is even harder, and I may very well succumb to them. Thus, you should ask yourself whether attacking giant-sized aliens with "normal sized" drones may not be a much better approach.
Lastly, seeing how those giant aliens crossed dimensions and can apparently just willfully ignore the square-cube law (and other physical laws?!), it seems that unless your understanding of the inner workings of the universe *drastically* changes, they are by all means invincible, so actually it might be best to just surrender and leave the planet to them. Maybe they'll be merciful to their eternal slaves...
] |
[Question]
[
Goblins are small, diminutive humanoid creatures. They are approximately the size of a small child, they are short-lived, and they have very low intelligence.
In my fantasy world, goblins have been bred and domesticated like dogs. They can be taught simple commands and tasks, though they lack the intelligence for any skilled labor. They can use tools, but they still require oversight. Their lifetimes are too short to be worth much investment.
They are basically dogs with opposable thumbs.
Goblins have been bred to work on castles, farms and stables, etc. doing all the menial jobs. They are best suited for repetitive tasks that require no thought.
They are not paid, and will work because that's what they've been bred to do.
Like dogs, some goblins are prone to distractions and will occasionally be mischievous. They cannot be trusted with anything valuable.
They have very little strength, but decent stamina. Goblins can also eat near anything, and are very easy to sustain - they will happily live off trash and leftovers. They have good sense of smell, they have night vision, and are decent hunters. They work well in numbers.
Domesticated or no, most animals will spook around goblins. Goblins are nocturnal creatures, and the sight of any fire has a hypnotizing effect to them. Even small flames can entrance them and large blazes will send them mad.
There is a risk of goblins going wild if left unsupervised.
Right now, I'm thinking that goblins will be used to wipe the floors and clean stables. Are there any other jobs in medieval-like setting where domesticated goblins could be employed?
[Answer]
Agriculture: Goblins can do anything larger animals can't do. It shouldn't be too difficult to teach them to harvest crops, vegetables and fruit, take care of the plants in general, get rid of unwanted weeds, sow seeds etc.
They might even lead larger animals for plowing.
Manufacturing can also be made easier. If they can clean, anything for textiles for example
- shearing sheep, spinning, weaving and so on - shouldn't be hard, and a lot more I'd assume. Later on they'd be ideal factory workers.
While their lacking strength can be a drawback, their stamina and size can also be useful in mining. Again, a support position is where they'd be best - move small rubble out of the way, collect and sort ore while the human miner works the pickaxe.
In general if goblins existed the way you describe them they'd be useful for almost anything at least in a support job. While they couldn't work as blacksmith themselves, for example, it wouldn't be a problem for them to operate the bellows, add coal to the furnace, clean and order tools and so on.
Other than typical work:
They can be employed as entertainment - circus, gladiator/pit fights, theater, possibly even music.
And, of course, they can be warriors. Give them spears, clubs and slings. They are faithful like a dog, but can handle weapons. Hell, they can even ride dogs for all I care... kinda depends on how uneasy domesticated animals get around them, but I'd consider it illogical to make dogs afraid of them if they live in the same household.
In other words, they'd be a part of every aspect of life and work. Nobody says no to a cheap and efficient worker.
[Answer]
Humanoid but not quite human, capable of tool use but of low intelligence, owned as property, used for unpaid manual labor?
What you're describing here, without actually using the word, is *a slave race.* So try looking at historical examples of tasks that slaves were employed for. And while you're researching historical slavery, you can find interesting examples of various things that can go wrong, and also various different models of slavery. The brutal style formerly practiced in the American South that people these days generally associate with the term was not the only option.
Also, a word of caution. Because American South style slavery is what most people think of, a lot of readers will make that association whether it's what you intend or not. And the traits of a slave race I listed above were often imputed to the African race in past times as a justification for slavery, and for racism after it was ended. (Yes, all of them. They were treated as literally subhuman, and the publication of Darwin's work on evolution, just before the American Civil War broke out, certainly didn't help; it gave scientific credibility to the notion that Africans were "less evolved" and closer to bestial animals than "proper humans.")
If you write about something like this, make sure that it's clear from the text that your goblins are not a fantastical counterpart to any real-world group of people. Otherwise, you run the very real risk of some oversensitive person claiming that they are and that you're a racist, a horrible person, etc.
[Answer]
Think about the first jobs ever that were replaced by some kind of machine or automaton. The goblins would be used for:
* Carrying water (for those households without running water)
* Collecting and carrying fire wood, stoking fires
* Loading and unloading freighters, wagons and caravans (let several goblins carry one heavy package)
* Substituting the conveyor belt in the first ever assembly line
* Food processing: harvesting fruit, peeling and cutting it to be processed into preserves
* Producing simple goods like clay bricks (to be burned by an intelligent human) and woven baskets
In times of war they could literally replace dogs and horses by transporting provisions and messages between the front lines and headquarters.
[Answer]
The goblins could,be employed by chimney sweeps, if chimneys have been invented yet in your world.
In the real world chimney sweeps would employ children as young as 5 or 6 to clean chimneys from the inside, often crawling up them without wearing any clothes as they cleaned the deposits of soot and tar.
This was hazardous work some children would die through suffocating as they climbed the chimney, some would slip and fall and some would be burnt to death as fires were lit in grates to 'encourage' them to work faster. The environment was also dangerous the deposits on the inside of a chimney are carcenogenic and many died of cancer, scrotal cancer in boys was a particular problem as they worked without clothes. Also respiratory diseases were a problem.
[Answer]
Thinks like a tannery or cleaning the collection points of castle toilets come to mind. Basically jobs that were done by slaves in Roman times or the poorest people in the Dark ages:
<https://en.wikipedia.org/wiki/Tanning_(leather)>:
Formerly, tanning was considered a noxious or "odoriferous trade" and relegated to the outskirts of town, amongst the poor. Indeed, tanning by ancient methods is so foul smelling, tanneries are still isolated from those towns today where the old methods are used. Skins typically arrived at the tannery dried stiff and dirty with soil and gore. First, the ancient tanners would soak the skins in water to clean and soften them. Then they would pound and scour the skin to remove any remaining flesh and fat. Next, the tanner needed to remove the hair from the skin. This was done by either soaking the skin in urine,[2] painting it with an alkaline lime mixture, or simply allowing the skin to putrefy for several months then dipping it in a salt solution. After the hairs were loosened, the tanners scraped them off with a knife.
<https://www.ancient.eu/article/1239/toilets-in-a-medieval-castle/>
Another design was to have tiers of toilets on the outside wall where the shafts all sent waste to the same collection point. Dover Castle, built in the second half of the 11th century CE, had a cesspit at the base of one wall of the keep to collect waste from the toilets above. At Coity Castle in Wales, built in the 12th century CE, there were three tiers of toilets with the shafts emptying into the same courtyard basement. The same arrangement was found at Langley Castle in Northumberland, England, built c. 1350 CE, with the common collection point being a pit which was cleaned out by a natural stream. There were also toilets in ground floor buildings and these had stone drainage channels to drain away waste. Waste from such collection points, or the ditch in general, was likely collected by local farmers to be reused as fertiliser.
[Answer]
With you description, it is easy to treat them as slaves as described in many of the other answers.
This could be a plot point for later rebellion or welfare groups.
Consider `The Stormlight Archives` where
>
> the parshmen (creatures of lesser intelligence) gain intelligence. By simply leaving, the society that has grown too dependent on them collapses.
>
>
>
If you want your society to take a more symbiotic relationship, you can exploit the fact that the goblins eat anything to create a sanitation system where they eat all the garbage.
[Answer]
War goblins obviously, send them in just before the first regular rank with knives and cheap spears in the hope of getting them to disprganize the enemy line just before the charge
[Answer]
Goblin mills.
Put into wheels just like hamsters, with decent stamina and low upkeep costs, they are perferct for the job - also, no intellectual skills are required.
They can work together in groups of 50-200 to power a stone grinder and produce flour
[Answer]
Mining. All mines used to be dug following the vein and with a bare minimum of extra material removed, so the tunnels were rather cramped. Goblins, much like children in the days gone by, were expendable, so this is an ideal place to put them to work.
Another industry where goblins would excel would be weaving/spinning (especially if your world experiences anything like the industrial revolution).
[Answer]
As others have said, basically any work that a slave would do. Easy to understand, yet repetitive and back-breaking. Think of similar jobs too, but much more on the scale of “stuff nobody wants to do”. Sewer and sanitation workers come to mind, mostly. In a medieval society, functional sanitation would have been the envy of everyone. The more goblins you have to clean up the sewers, and solid waste/garbage clogging up the streets, the cleaner and more beautiful your city would be to everyone, and more people that could do more valued or important work. Just an example of how it could work.
[Answer]
Place them in the mines if there are any in this world. You can work em real hard if you're not paying them. Assuming they don't attack folk with pickaxes.
] |
[Question]
[
The situation I'm considering is as follows:
A space ship (a transport ship operated by two people) crashes onto a planet on which a swing-by was planned. The crew could escape using an escape capsule and land on the planet, while the space ship crashed on it. The escape capsule lands not too far from the crashed ship.
The planet has only a very thin atmosphere, so one can assume that the space ship did not burn up in the uncontrolled fall (however, I don't know how thin the atmosphere has to be to allow that, but since the planet is very hostile and the crew will need space suits outside anyway, I can make is as thin as needed).
Now my idea is that the crew will rescue some things from the ship wreck (like food reserves). But that of course assumes that anything could actually have survived the crash.
Therefore my question: Could such a crash realistically happen in a way that things could be rescued from the ship afterwards? Note that the things don't have to be in a particularly good shape, just good enough to be useful at all.
[Answer]
This is all down to velocity, the only way to make anything of the ship survive is to slow down the descent a lot.
My suggestion would be to have the ship come in under power, but only just. At the last minute the crew eject when they realize they are still coming in too fast.
This both gives you a good explanation for why they end up close together and explains as much or as little of the crash as you would like surviving.
[Answer]
**It depends**.
There are a few main factors to consider in determining whether any given thing will have survived.
1) **The Speed(and angle) of Impact** The faster the fall, the less likely it is that any given thing will have survived. High speed collisions could embed the ship in the ground and/or pulp it entirely, making recovery effectively impossible, regardless of other factors. The angle also plays an important role: a ship falling straight down is going to be in worse shape than one impacting at the same speed but at an angle. On the other hand, a ship impacting at an angle could have parts thrown a great distance from the impact site, making recovery easier in some ways, but much more time consuming.
2) **The Site of Impact** Harder surfaces will cause more stuff to be destroyed, but less stuff to be lost. If something goes flying, it's more likely to embed itself in the ground somewhere if that ground is soft. Flatter surfaces are probably going to be more amenable to recovery in general than forests or hills.
3) **What you Want to Recover** Different supplies take different amounts of force to break and are stored in different ways. Food could be much more difficult to recover because it's much more fragile than the plasma guns, but it could also be much easier because it is likely to be stored loosely, and therefore could be thrown out of the ship to safety much more easily if the hull is broken. Which brings us to the last consideration.
4) **The Ship's Design** Did the people who made the ship anticipate that it might need to survive a crash landing? If so, what parts did they prioritize for survival? Did it have emergency systems to kill speed during a crash? Did they activate in this case? How effective were they? Did the designers include some sort of emergency black-box thing which could survive things the rest of the ship couldn't? What did they put in it? Why those things and not others? You can justify almost anything surviving in some quantity provided that you can come up with some reason why the designers would think it cost-effective for it to do so. You just have to figure out who made the ship, and what their incentives were.
[Answer]
Most of the current answers assume that you're very set on the characteristics of the planet and offer suggestions on what sort of ship and what sort of scenario would be necessary to recover what bits.
But you state:
>
> The planet has only a very thin atmosphere, so one can assume that the space ship did not burn up in the uncontrolled fall
>
>
>
For the sake of this answer, I'm assuming you've decided the planet has a thin atmosphere because:
1. You don't want the ship to burn up during entry.
2. You want the planet to be hostile.
So first, let me address those two issues.
On point one, is the ship never intended to ever have a controlled landing on any other planet ever? Is this purely a single surface launch vehicle that then just goes between space stations in orbit?
If this ship is intended to ever land on any other planet, isn't it safe to assume that it could survive some degree of entry effects?
On point two, this is probably pretty obvious, but it's quite easy for the planet to be hostile without having a thin atmosphere. Thick atmosphere's aren't inherently breathable atmospheres.
---
I also want to second the recommendation of checking out Kerbal Space Program. In fact, it'd be a good way for you to simulate in a moderately realistic manner crash-landing into planets of various characteristics and seeing what kind of somewhat realistic results you might get. And the rest of this answer will based on some of my observations of the pretty realistic physics of Kerbal Space Program.
So with that said, assuming the ship would be capable of withstanding a thicker atmosphere in entry (because it's probably designed to land somewhere at some point), here are my observations of landings (and attempted landings) on planets of various characteristics.
The two factors of a body that most effect landing are their gravity and their atmosphere. Lower gravity means the planet pulls you in with less acceleration, and denser atmosphere means there's more aerodynamic drag to slow you do. So an ideal planet to have to crash land on would be one with low gravity and high atmosphere (presuming it's not so high the ship burns up).
We can also improve our chances by making the insertion angle quite shallow. Another answer addresses the angle of impact with the actual surface of the planet, but the angle of "impact" with the atmosphere can be important as well.
With too shallow of an insertion angle, the craft will essentially skid right across the atmosphere. If the ship hasn't escape the planet's sphere of influence, it will be forming a highly elliptical orbit, which if still crossing through the atmosphere, will eventually mean a disastrous landing as the ship will eventually come in with a very deep insertion angle.
A better insertion angle would be one that allows us to spend much more time in the atmosphere. The exact angle you'd want? I'm not quite sure.
If your vertical velocity is too high, everything will be destroyed. If your horizontal velocity is too high, everything will be destroyed.
On a planet with a very thin (or nonexistent) atmosphere and a non-functional ship, I'm not sure I can imagine a successful landing at all. However, with low gravity and some functional engines for some retroburning, it wouldn't be too terribly far-fetched depending on the exact scenario.
On a planet with a thicker atmosphere however, there's much more to be done to slow the ship down--particularly if it's equipped with parachutes that could be manually deployed. Without functional engines for retroburning however, a survivable landing still seems very far-fetched. With no engines whatsoever, you essentially need an atmosphere to almost completely nullify the vertical velocity (lower gravity helps but makes gravitational capture less plausible), and a very, very shallow impact angle... and a ship capable of skidding across the surface... and a little bit of luck to ensure there's no geologic features to crash into. (It is suspected that the satellite "Beagle 2" which was intended to have one of these skid-landings on Mars was destroyed when it skidded into the cliff-wall of a crater.)
---
It might be worth reading about [how the Space Shuttle re-enters and lands back on earth](http://en.wikipedia.org/wiki/Space_Shuttle#Re-entry_and_landing). The space shuttle uses OMS to alter its orbit into the atmosphere. From here, it relies purely on [RCS thrusters](http://en.wikipedia.org/wiki/Reaction_control_system) and [control-surfaces](http://en.wikipedia.org/wiki/Flight_control_surfaces) (which is a fancy name for flaps--essentially the same as what's on any other airplane) to control itself in order to get the perfect balance of aerodynamic drag. Have to be mindful of heat, but also need to slow down. Once it reaches the lower atmosphere, it's not much more than a really expensive glider.
Once the shuttle actually touches down, a drag chute is applied to slow it down.
The space shuttle lands on a paved runway on wheeled landing gear. This seems unlikely for a crash... but presumably your ship could land in a very similar situation but simply skid across a plain and take fairly minimal damage given that it's just been in a crash... in space...
It'd also be completely believable for the engines to be completely useless but for RCS thrusters and control surfaces to still be completely functional. Control surfaces are most likely powered by electric servos and therefore powered solely. RCS thrusters generally use a different type of fuel. It's just an entirely different system altogether from the main engines.
[Answer]
Thin atmosphere may be both a blessing and a curse in this scenario. While a thin atmosphere reduces the chances that the spaceship will burn up during an uncontrolled reentry, it also reduces the opportunity for aerobraking (slowing the spacecraft through friction by grazing the atmosphere), which is your best way to reduce the speed with which the spacecraft plows into the ground.
A lot of the outcome depends on the point at which the ship becomes an uncontrolled projectile. Assuming that the crew are able to perform at least some degree of deceleration (either via aerobraking or retroburning), then they may not need to bail out until the craft is in the low atmosphere, at which point the craft will be traveling relatively slowly, and a significant portion of the craft could survive impact.
The recent crash of Virgin Galactic's Spaceship Two provides some evidence to support this theory. Despite the tragic loss of life, photographs from the crash site indicate that significant portions of the spacecraft remain intact.
[Answer]
I would want to know what "crash" means. There would be some level of control during descent which would be utterly mandatory if the vessel was traveling from anywhere but the planet itself (i.e. from another planet or other solar system).
Think about the speeds you need to travel from one planet to another. If there is no slowing down, your impact will be faster than anything NASA has been able to reproduce in a lab (easily in excess of 100x faster than a bullet).
Now if you successfully slow down to orbital velocity and THEN lose control and crash, now it gets more interesting. Just doing $E=mgh$ will show the amount of energy to disparate would crush anything in existence unless it was a very small object and the entire space-ship was designed to cradle it during impact.
Which brings me to a final answer: what if "crash" just means "we couldn't control it as well as we wish?" The Apollo mission capsules returned by using ablative shielding to slow down from orbital speeds and then relied on parachutes to slow it down the rest of the way for impact. Martian landers have relied on parachutes as well. I think it would be totally reasonable for a ship to be equipped with emergency measures such as parachutes which do not technically constitute a landing, but could be easily controlled by computers like we had 30-50 years ago with a high degree of reliability.
The only question would be whether someone would justify the mass of the parachutes as a safety mechanism. They might intentionally design the ship to break up into unessential pieces and essential pieces, so they didn't have to bring enough parachutes for the entire ship, only the parts which one would wish to salvage in such an extreme event. Alternatively, there could be a political pressure demanding such safety mechanisms exist, such as to avoid polluting foreign planets with debris.
[Answer]
As people have said, for an interplanetary ship to hit a planet in full flight, the question is more whether you could retrieve items from the *planet* afterwards. So, you'd have to assume some kind of emergency system allows the ship to land anywhere near intact.
Perhaps most of the ship's mass is its mechanical systems, and the crew compartments are a relatively small capsule at one end; as a last resort, it fires the crew module backwards with some sort of explosive bolts, sacrificing the bulk of the ship as reaction mass to put the most valuable part into a survivable landing trajectory.
That would explain why a ship with no engines can do a controlled landing, but also make it plausible that the landing would damage it badly (the damage is expected, but this is a last-ditch measure). Unlike boats or even planes, spaceship crashes are pretty black-or-white-- it's either a perfect landing or a smoking crater.
It might be convincing for the ship to take a long time (days?) to come out of orbit; as it descends it looks for survivors / good landing sites, slowly adjusting course with small drag chutes.
[Answer]
The premise I've read thus far adds that there is little to no engine power, yet the crew are working through a gravity assist. That would mean the trajectories were calculated some time prior and the ship is coasting through.
An undetected moon might be more than capable of changing a gravity assist's result. Coming in at the wrong angle with respect to a large moon could result in an accidental gravity-assisted brake. The ship could drop into a high altitude orbit around the planet instead of being expelled from it as originally planned. In a scenario like that, the orbit of the ship after the braking would probably be further out than the moon.
Given the lack of engine power, the ship might be stuck in orbit. Toss in a failure of the solar radiation safety mechanism for impetus to get off the boat. They bail using emergency escape pods, where some contain people and some contain supplies. Instead of seeking out the ship as originally desired, the crew would be seeking out the supply pods like Easter eggs.
An additional quest might be figuring out how to get back to the ship in its high orbit for some MacGuffin.
[Answer]
The NASA [Genesis Mission](http://en.wikipedia.org/wiki/Genesis_(spacecraft)) (see recovery phase) is relevant. The plan was to enter the atmosphere, descend by parachute and be caught by a helicopter before it hit the ground. The chute failed to deploy and the craft slammed into the dessert but scientists were still able to recover useful samples from the craft even in its damaged state.
[Answer]
Depending on how 'soft' the landing is, there might be some salvageable raw materials, and maybe a few recognizable pieces, but have you seen pictures of aircraft crashes? It's a mess.
Food stuffs would be most likely almost unusable probably unrecognizable. However, I would expect an escape pod to have the minimum supplies needed for however many people it was designed for. Enough for a minimum expected possible rescue attempt. It should also contain some minimum equipment such as shelters for a landing and a water purifier/recycler etc.
[Answer]
I would say it depends.
What is the ship made of, how much if an impact can it take, what's the gravity of the planet, mass of the ship (and tberefore force of impact)
Look at the effects of plane crashes. Full speed into the ground is worse than gliding in to a hard skid or river. Both are crashes. Coming in from orbit with no atmosphere and earth like gravity I'd expect it to be a very violent collision at 5km/s or more, creating a crater and/or tearing apart any current manmade materials.
[Answer]
I think another defining factor is how large the ship is to begin with. If you have more components (more engines, wings (for a spaceplane), landing gear, etc.), there's a greater chance that *something* will be damaged, but a smaller chance that *everything* will be damaged. If you take 10 engines and spread them out along a spaceship, the craft would have to be totally obliterated for none of them to work. Chances are, you'll get a couple that are okay. And if one of the crew is mechanically adept (I hope!), a few more could be salvaged.
That said, you won't be able to rebuild the original ship. A lot of crucial components will be damaged or destroyed. But you can probably make do. If an [X-wing](https://en.wikipedia.org/wiki/X-wing) fighter crashes on a planet, the upper (or lower, depending on the angle) two engines could be intact. You might also have damage to one set of wings (again, it depends on the approach angle and, in this case, if the wings were spread out or bunched together). You won't be able to re-build the X-wing, but you might be able to cobble together some two-engine craft that can get off the planet.
[Answer]
Some material does survive from the bigger ships falling from space. When [Skylab](https://en.wikipedia.org/wiki/Skylab#Re-entry) went down, debris were found on the ground. Or [Columbia](https://en.wikipedia.org/wiki/Space_Shuttle_Columbia_disaster#Recovery_of_debris). Mir space station required deorbiting into uninhabited area of the ocean, and it is known that parts of Hubble may survive reentry. Of course, depends on the spacecraft and depends on the planet, but generally possible. You may assume that the ship has completed some part of the landing sequence to make this more realistic.
] |
[Question]
[
**This question already has answers here**:
[My time machine needs to know when it is](/questions/116454/my-time-machine-needs-to-know-when-it-is)
(31 answers)
Closed 3 years ago.
Specifically, I'm considering a situation where:
* The entire planet, as well as all other bodies in the solar system are sent forward in time fifty years, so it's not possible to notice purely from observing bodies within the solar system (in effect, the rest of the observable universe has changed, but not our solar system)
* Since the whole solar system is affected, the positions of Earth and the planets/Sun have not changed relative to each other --- only relative to other star systems
* The astronomy practices and precision of equipment are those of Earth today
* The Sun and solar system will be in a new location, as though it had continued to move through space for fifty years
What sort of plausible situation would lead an academic to notice something was wrong, in the course of routine observation or research?
My first thought is that you may be able to notice the change in position based on parallax of nearby star systems. However, I don't have a great sense of whether fifty years would make a big enough difference to notice with the precision of today's instruments.
If your solution works for fifty years, would it work for five years? Or six months? And if not, would it work for five hundred?
[Answer]
This would be noticed rapidly by observations of stars with high [proper motions](https://en.wikipedia.org/wiki/Proper_motion). These are stars that through a combination of being close to us, and moving at high velocity relative to us, move noticeably against the background of more distant stars over the course of a few months. It so happens that there are no stars with high proper motion that are visible to the naked eye, but there are several that are easy to detect with a small telescope or binoculars.
The best-known star with high proper motion is [Barnard's Star](https://en.wikipedia.org/wiki/Barnard%27s_Star), which is frequently studied as an example of a red dwarf. Almost any professional observations would notice that it was out of place with a five-year jump. Indeed, it's likely to give away any jump of more than a week, since its motion is 10.3 seconds of arc per year, and measurements of its position are taken to an accuracy a tenth of a second of arc or better. Once discrepancies had been noticed, a survey of high proper-motion stars would reveal what had happened within a few weeks. This method works for any period of time.
And that's discounting the [Gaia satellite](https://en.wikipedia.org/wiki/Gaia_(spacecraft)), which is engaged in measuring the positions of about a billion stars to an accuracy of about 20 *millionths* of a second of arc. Your time jumps would cause its operators to think the satellite had malfunctioned at first, but they'd soon have evidence of what had happened, although accepting it might take a long time.
An alternative explanation might be a glitch in a simulated universe. A way to check that would be to look for glitches in the beam currents of particle accelerators at the right moment. Teleporting particles moving very close to lightspeed, along with everything else, might be tricky.
[Answer]
Your astronomer has a number of options.
1. Binary stars. Many binary star offer orbital periods in excess of 50 years. For example, [Alpha Centauri](https://en.wikipedia.org/wiki/Alpha_Centauri) A-B pair has orbital period of about 80 years, and Proxima Centauri - about 547,000 years. By observing this system and comparing it to "present", an astronomer may find the amount of time passed with good precision.
2. Nova/Supernova nebulae. After Nova or Supernova goes off, a fast expanding cloud of gas can be visible from Earth. These nebulae are a short-living phenomenon, they exist on scales of only hundreds and thousand of years. By studying the size of a known nebula, an astronomer can estimate how much time has passed.
3. Pulsar slowdown. Pulsars are known as a very precise clocks, but they do slow down with time. This is particularly noticeable for young pulsars. For example, [Crab Pulsar](https://en.wikipedia.org/wiki/Crab_Pulsar) is known to slow down by 38 nanoseconds per day. With the help of an atomic clock, this slowdown can be measured.
[Answer]
There are a ton of things we have telescopes pointing at that would definitely notice a 50-year jump. John and Alexander's responses are excellent examples. Here are some more:
1. **Exoplanets**: There are [dozens](https://en.wikipedia.org/wiki/List_of_exoplanet_search_projects) of active projects searching for planets orbiting around other stars. All telescopes involved in this kind of research would notice that the incredibly regular periods of all of their exoplanet candidates all shifted at the same time. It won't take long to realize that only a 50-year gap in data could cause these exact shifts in phase to line up across every system.
2. **Pulsars**: These neutron stars have extremely precise rotation rates, beating continuously in the night sky every few seconds across a swath of frequencies. Of course, like just about everything in the sky, we're actively measuring a bunch of them. If every pulsar in the sky skipped a beat, it would be a headline immediately, and again, by comparing the different frequencies of the skips, we could calculate that we skipped 50 years. In fact, pulsars might be the most accurate measurement of the skip that we have - you could probably pinpoint the 50-year time difference to within a fraction of a second.
3. **The Expansion of the Universe**: The universe is expanding, and that expansion is speeding up. This means that, 50 years from now, some particularly distant objects will be moving away from us much more quickly than they are now. Some current research is probably sensitive enough to pick up on this by measuring the redshift from those distant objects. Again, they'll notice a sudden skip in their data, though they won't be able to pinpoint 50 years as accurately as the exoplanet or pulsar researchers.
I imagine grad students around the world will spend the first few days yelling at their data, wondering if their telescopes malfunctioned or something. As the complaints spread around universities, it will quickly become extremely conspicuous that every project has exactly the same "glitch." I give it a few weeks at most before people figure out what happened.
EDIT: To answer your question,
>
> If your solution works for fifty years, would it work for five years? Or six months? And if not, would it work for five hundred?
>
>
>
the answer is a resounding yes for all of the above (at least for exoplanets and pulsars). Even if you're observing just 2 pulsars whose frequencies aren't multiples of each other, as long as you know their frequencies and phases precisely, you can calculate any length of time. If, for instance, when the skip happens, the first pulsar is at 93.0056 degrees and the second is at 202.4855 degrees, you know exactly what time it must be, because those pulsars will only be in that position once in the history of the universe.
There will probably be some uncertainty in the frequencies, so some other times might give configurations that are "close enough." But we can measure frequency so accurately these days that I'd imagine your calculation would give something like, "we've moved exactly 50 years, or 20 billion and 50 years, or 40 billion and 50 years, and so on." But you can rule out all but the first by noting that Andromeda hasn't crashed into the Milky Way yet.
[Answer]
There are already a number of very reliable methods in the other answers (and frankly, I'd only posted a comment if I could). I want to offer an answer more directed towards a plot or story element if that is where you want to go with the question:
## Comets
Depending on how you define "solar system", there are [objects](https://en.wikipedia.org/wiki/Comet#Long_period) that occasionally visit our solar system (in the sense of roughly the space occupied by our planets' orbits). They often do so periodically and one of such encounters to happen fifty years early would probably cause confusion at first (some people claiming to have found a new object until they realize it's a known comet), but could lead to the theory of having performed a jump in time (which could then easily be proven/made believable with one of the other methods mentioned here).
This method is definitely not the most precise or practical one (it only works if a comet happens to pass by right now) and it needs further definition of your situation (Does everything that orbits our sun jump, even if it is far outside of the solar system? Do we jump in space or just in time - which could also result in a comet's regular orbit to cut through the solar system in an unexpected way?
It does however offer multiple options for story telling (from your astronomer being the one to first recognize the object as C/1905 F1 to the object dramatically colliding with the moon due to its shifted orbit) and allows for a fairly precise guess of the jumped time period, once it is identified.
[Answer]
Depending on what you mean by the solar system, an early probe like voyager might be 50 years along further than you'd expect and that much harder to detect.
Might make for an interesting first scientific hint.
[Answer]
## The Hulse-Taylor binary
The Hulse-Taylor binary consists of a neutron star and a pulsar in a tight orbit. These two objects emit gravitational waves at a known rate, which causes the period of their orbit to slowly decrease with time. This change in orbital period was the first indirect evidence for the existence of gravitational waves, and netted Hulse & Taylor the 1993 Nobel Prize in Physics.
[](https://i.stack.imgur.com/iEWvi.png)
This is a distinct effect from the slow-down of a pulsar's rotation rate (as mentioned by other answers). Here's how I would imagine things playing out:
* A significant number of pulsars experience a "glitch", since the 50-year jump will not be an even number of cycles for most of them.
* Examinations of the Hulse-Taylor binary would then show that the period is decreasing at a much higher rate than one would expect. Further examinations would then be able to estimate the amount of time "skipped", probably to an accuracy of a couple of years.
[Answer]
Very good answers so far, so just adding two approaches:
## Statistics
* If one star is suddenly at the wrong place / have the wrong brightness fluctuation, that's a measurement error.
* Two stars? better refine your Gaussian filters.
* Thousands of small variations registered across the board (local stars, distant galaxies)? Something is deeply, deeply wrong.
Bonus statistical event: [according to Wikipedia](https://en.wikipedia.org/wiki/Nova), "*[...] the number of novae discovered in the Milky Way each year [is] about 10.*" Imagine that ~500 new novae detection events suddenly pop up (or at least their remnants after 50 years or less).
## Event Horizon
Time has slowed down around the solar system. That means that incoming photons are accumulating in a bubble around the affected area due to time dilation, not completely akin to a black hole's event horizon, and if the time taken by the jump as experienced by local observers isn't zero these photons will arrive at a rate defined by 50 years divided by the local duration of the jump.
So, if the jump takes, say, one hour - that means that the whole sky will light up with 438,000 times the normal intensity.
As a reference: [the Sun is 400,000 times brighter than the full Moon in the sky](https://www.discovermagazine.com/the-sciences/bafact-math-the-sun-is-400-000-times-brighter-than-the-full-moon).
Imagine that kind of brightness difference *coming from all directions*.
In that case it's safe to assume that every single able-bodied person will *notice* the event, but a scientist can actually come up with a the correct cause, as several indicators (brightness variance, relative star motion, pulsar rates, etc.) will show the same multiplier value of ~438k.
[Answer]
Ten seconds after this time jump, the first amateur astronomer somewhere on the world says "what the hell where is that asteroid I was just looking at?" One minute later, he has found and identified at least one of Venus, Mars, Jupiter, Saturn at a very odd place. (To anyone who has looked at the skies at night often enough, they just *stick out*.) From there on, he is texting, telephoning, emailing like crazy.
After one hour, every astronomer in the world who has not set his phone on mute before going to bed will be informed about the exact lenght of that time jump, provided the communication systems (due to GPS malfunction, or sheer overload) are still online.
Everybody will try to find something that hasn´t jumped, and astronomers immediately check positions of nearby stars according to their known proper motion, and pulsars. After another hour, it will be around the world that the rest of the universe is still where it was about three hours ago. And at this point, the plot will turn into a "whodunnit" story. Let´s hope you were very discrete with your time machine setup. ;)
[Answer]
This could be a comment, but is probably too long for one.
What does the OP mean by:
>
> The entire planet, as well as all other bodies in the solar system are sent forward in time fifty years, so it's not possible to notice purely from observing bodies within the solar system (in effect, the rest of the observable universe has changed, but not our solar system)
>
>
>
"All other bodies in the solar system" include the Sun, seven other planets, at least 5 dwarf planets, possibly the hypothetical Planet Nine, about a million known minor planets or asteroids, hundreds of moons of the planets, Thousands of Trans Neptunian objects in the Kuiper Belt, hundreds or thousands of known comets, and the million, billions, or trillions of undiscovered comets believed to be in the Oort Cloud, etc.
If any of the known objects are left behind, sooner or later some astronomer is going to take a look at them and discover that they are not where they used to be. And if astronomers keep looking to see if other know objects are are actually in their predicted positions, they will soon compile a list of which ones are and which ones aren't. And by compiling lists of the latest dated observations of various now missing objects, they will be able to get a good idea for when those objects disappeared.
And it seems to me that the angles between the Sun, the Earth, and another body orbiting the Sun are constantly changing as both the Earth and the other object orbit the Sun with different speeds. The period between successive moments when another body orbiting the Sun happens to be at the same Angle relative to the Sun and the Earth is call its synodic period.
Here is a link to a table of the synodic periods of the other seven planets, and 9 other bodies that orbit the Sun, relative to the Earth.
[https://en.wikipedia.org/wiki/Orbital\_period#Examples\_of\_sidereal\_and\_synodic\_periods[1]](https://en.wikipedia.org/wiki/Orbital_period#Examples_of_sidereal_and_synodic_periods%5B1%5D)
Each object has a different synodic period. So try to calculate how much time will pass before an even number of each and every one of those 16 synodic periods passes and all 16 bodies are at the same angles relative to the Sun and Earth as they are this very moment.
Furthermore, a planet will not be in the same direction relative to the background stars after a full synodic period has passed. For each body, there must be a certain number off full synodic periods which will pass before the planet is both in the same angle relative to the Sun and Earth and also in the direction relative to the background stars. So since those other periods for each body are several - probably very many - synodic periods long, The time that it would take for all those 16 orbits and synodic periods to realign and be the same again should be extremely long.
it is my belief that even though the apparent directions to the stars shift very slowly due to their immense distances, the time for such a realignment would be so long that the stars would have shifted their apparent positions so much that the shapes of the constellations would clearly be different. So I believe that the apparent positions at any one moment in time of those 16 bodies listed will never be the same again in the billions of years of future history of the solar system, that it is a unique configuration.
And there are are many other solar system objects beyond the 16 in that list, which are also routinely observed by both amateur and professional astronomers.
And what about bodies that orbit other solar system bodies?
Amateur astronomers often observe the four Galilean moons of Jupiter, perhaps often enough for them to be under constant observation, which might mean that someone would actually see them disappear in real time if they are left behind in the time jump.
A few decades after the Galilean moons were discovered, tables predicting their movements were published. If someone observed their apparent positions, passing into the shadow of Jupiter or other moons, casting shadows on Jupiter, occulting other moons, passing behind Jupiter and emerging from behind Jupiter, etc., etc., and noted the local time using an accurate clock, they could compare those local times with the times predicted for some other location in the published tables. And they they could calculate the difference in local astronomical time between the place where the observations were made and the place where the predictions were made for. And thus they could calculate the difference in longitude between the two places.
This method was first used to find the longitude of places more than 350 years ago.
And there are tens of other moons in the solar system with well predicted orbits. Those other moons will also have to be moved by the super science and technology, or extremely powerful magic, used in the story, in order to keep the Earth humans ignorant of the time jump for as long as possible.
So if the beings (?) who move the solar system forward in time by 50 years move only ten solar system objects and leave the rest behind, it is quite possible that some amateur astronomer will be looking at one of the objects left behind, and will actually see it disappear from view, and/or be making a video recording of it, at the moment it disappears. So moving only ten solar system objects forward in time may result in instant discovery that something strange has happened.
If the one hundred solar systems objects most likely to be observed are moved forward in time it should take longer to discover what has happened.
If the one thousand solar systems objects most likely to be observed are moved forward in time it should take a longer time to discover what has happened.
If the ten thousand solar systems objects most likely to be observed are moved forward in time it should take much longer to discover what has happened.
If the one hundred thousand solar systems objects most likely to be observed are moved forward in time it should take even longer to discover what has happened.
And so on and so on.
If thousands or millions of solar system objects are moved forward in time and space by fifty years, it would be a very complicated operation, especially making certain that all of them are in their proper positions and orbits relative to each other.
So if the objects are moved in time and space individually, the number of objects which are moved instead of being left behind will determine how quickly professional and/or amateur astronomers discover something very strange has happened.
The best way to delay detection of the move in time and space would be to move everything in the solar system.
So I can imagine some sort of time warp field being generated which covered the entire solar system and moved the entire solar system with many millions, billions, trillions, etc. of objects all at once.
One way in which amateur observers help professional astronomers is by observing variable stars and recording their apparent magnitudes, thus keeping track of the lisght curves of many variable stars.
Another way in which amateur observers help professional astronomers is by observing binary stars and recording the position angles of the stars in them, thus keeping track of the changing apparent positions of the stars and providing data for calculating the orbits of the stars.
And the organizations that the amateur astronomers send their reports to will soon be flooded with reports of variable stars suddenly changing their apparent magnitudes and double stars suddenly jumping around in their orbits.
In the 20th century, astronomers often took long exposure photographs of astronomical objects to show details which were too faint to be seen instantly. And if professional and/or amateur astronomers still do that in 2020, all such photographs of other stars, star clusters, and nebulae taken in time periods including the jump should include duplicate and probably overlapping double exposed images of those distant astronomical objects, as the directions to those objects change over 50 years of time.
The OP wrote:
>
> My first thought is that you may be able to notice the change in position based on parallax of nearby star systems. However, I don't have a great sense of whether fifty years would make a big enough difference to notice with the precision of today's instruments.
>
>
>
>
> Proper motion is the astrometric measure of the observed changes in the apparent places of stars or other celestial objects in the sky, as seen from the center of mass of the Solar System, compared to the abstract background of the more distant stars.[1](https://en.wikipedia.org/wiki/Orbital_period#Examples_of_sidereal_and_synodic_periods)
>
>
>
[https://en.wikipedia.org/wiki/Proper\_motion#:~:text=Proper%20motion%20is%20the%20astrometric,of%20the%20more%20distant%20stars.[2]](https://en.wikipedia.org/wiki/Proper_motion#:%7E:text=Proper%20motion%20is%20the%20astrometric,of%20the%20more%20distant%20stars.%5B2%5D)
>
> Proper motion was suspected by early astronomers (according to Macrobius, AD 400) but a proof was not provided until 1718 by Edmund Halley, who noticed that Sirius, Arcturus and Aldebaran were over half a degree away from the positions charted by the ancient Greek astronomer Hipparchus roughly 1850 years earlier.[23]
>
>
>
[https://en.wikipedia.org/wiki/Proper\_motion#History[3]](https://en.wikipedia.org/wiki/Proper_motion#History%5B3%5D)
So ancient astronomers using naked eye observations suspected proper motion over a period of centuries.
in 1716 Halley proved that Sirius, Arcturius, and Aldebaran had proper motion equalling about 0.162 arc minutes per year, or about 0.972 arc seconds per year.
So in 50 years they might show a proper motion of about 48.3678 arc seconds. Modern astronomical instruments record angles with a precision of 0.001 arc second or better, so they should be able to record the difference in the positions of Arcturus, Sirus, and Aldebaran in a time jump of only one day.
Barnard's star has the largest known proper motion, moving 10.3 arc seconds per year, which is about 0.028 arc seconds per day and about 0.00117 arc seconds per hour, just about detectable at a precision of 0.001 arc seconds.
[https://en.wikipedia.org/wiki/Proper\_motion#Examples[4]](https://en.wikipedia.org/wiki/Proper_motion#Examples%5B4%5D)
The Gaia satellite can measure positions of stars with an accuracy of 20 microsarcseconds, or 0.00002 of an arc second, and thus would be barely able to measure the displacement of Barnard's star in a time jump of one minute, and the displacement of a star with typical proper motion in a time jump of a few months.
] |
[Question]
[
In a few science fiction settings, we can see computers being called differently. A terminal, a holosphere, a pad, anything techno-sounding.
But from when computers were invented up until now, they've been renamed a few times and it never caught on. Micro computers, personal computers, portable computers... Basically, the main word remains computer.
In the same way, a phone remained a phone, a watch a watch, even though they've tremendously evolved.
Is it foreseeable that a change in the technology would bring on a new name for these devices? If so, what would be a likely name for it?
---
*PS: for the story, this question was asked to us by MIT Media lab Director's Fellow JJ Abrams in 2013.*
[Answer]
TL;DR: "Computer" will likely become an implementation detail, like "transistor" is to a computer today.
Historically, "computer" [referred to a person carrying out computations](http://en.wikipedia.org/wiki/Computer#Etymology). Like if we called a saw a "carpenter".
Of course a carpenter does more than just saw, so we separate the job description from the tools employed. Human computers, however, literally just did computation, so the name fit the (machine) computer equally well.
As computers have taken on more and more roles, they've just taken over the name of whatever they replaced, though not always a thoroughly as with the original computers.
I suspect the word "computer" itself won't be replaced with any single word, but rather that it'll become a word like "transistor" or "capacitor" - an implementation detail.
For instance, tablets are a pretty new category of computer. It's a computer, but I don't think many would call a tablet a computer in day-to-day speech. Sure, you can point at a tablet and say "that's a computer", and people would agree, but if you asked someone "have you seen my computer?" they'd probably think you're looking for a laptop or desktop PC.
Even the fact that we can use "laptop" interchangeably with "computer" hints that the idea of a computer is less important than the form factor. On the other end, we have mainframes and servers - still computers, but they have their own nomenclature regardless.
The same works for phones, gaming consoles, and other gadgets. Obviously they're computers, but we don't call them that. We also distinguish Mac from PC (which is even stranger, considering *both* fit the description "personal computer", but that's a historical quirk).
Heck, you can point to washing machines, cars, and thermostats and say they're computers - and you'd be right, but more people would wonder what you mean. It just fades into the background.
One could also take the co-opting human job descriptions further: If a computer is making trades on the stock market (as they've just done millions of times in the past couple of seconds), aren't they, in effect, "traders"?
[Answer]
If there is a change, I would guess it would be either because of slang or genericization.
1. **Slang** - When you think about it, we've given a lot of things new names, mainly just shorter versions of their original name. For example: $\text {Telephone} \rightarrow \text { Phone}$, or $\text {Hamburger} \rightarrow \text { Burger}$. I can see shorter terms being used - perhaps *puter* or *comp*. Odd, right? But I can assume we'll see something like this eventually.
2. **Genericization** - You might have come across this one in your daily life. Do you know someone who owns an MP3 player? One that isn't an iPod? Well, perhaps you've come across the following scenario:
Person #1: *Cool iPod. When did you get that?*
Person #2: *It's not an iPod. It's a(n) [insert name of MP3 player].*
Person #1: *Whatever. Cool iPod.*
Believe it or not, I've seen this phenomenon. When one brand of product becomes so ubiquitous throughout a certain market, people start to call *all* products similar to it by that name. Kleenex. Powerpoint. Iphone. So if, in, say, 50 years, a company called, say, Stillnexer (or an even weirder name) comes out with a new version of a computer, there's a chance that the term for 'computer' may become 'Stillnexer'.
---
Thanks to Ibrahim Arief for pointing out the name of the word I was trying to think of: Genericization.
[Answer]
In my opinion, the transformative technology will be natural language processing with ever more advanced learning software. I think there will be a shift from identifying with devices to identifying with software ecosystems. I openly admit I'm stealing from Vernor Vinge's Rainbows End.
Assume devices continue two important trends toward a) smaller and malleable b) interconnected. An example that supports these trends would be wrist sized computers that measure heart-rate, gait and connect via blue-tooth with a phone device, responds to phone based software, report data etc.
If you buy into this assumption, then the argument is as follows:
The size of devices goes down while capability and quantity per person goes up.
Interconnectedness of these devices depend on shared software ecosystems (or at least intentionally compatible).
Natural language and learning comes along and provides one common user interface to mediate user interaction.
Now many devices sharing a single software ecosystem are controlled through one software interface.
The user naturally begins to identify less with the individual devices they have/wear/own and more with the spoken interface through which they interact with them all.
I felt Siri, Cortana and Google Now were all somewhat silly... but I do think they are forward thinking in the correct direction. Cripes... my own parents are already referring to their new tablets and phones by first names, Cloe and Susan. Wait until they can carry on a conversation and the notion of "computer" will just start to be obsolete.
So to answer the second half of your question, I think computers will be referred to through chosen personal pronouns, or possibly a generic descriptor such as 'interface', that we assign to represent a collection of devices and services. For instance, I often refer to google and the internet as the 'Oracle'. "Do you know who has the greatest vocal range of popular singers?... I dunno, why don't you ask the Oracle?"
[Answer]
This is a strange question to me. Will computers be called computers in the future?
My phone is a computer, and nobody calls it a "computer" in casual conversation **today**. If someone said "pass me your pocket computer", it would be a strange affectation.
And it is a computer, with the processing power of a supercomputer from a decade or two ago (multi-core multiprocessor, faster than a gigahert clock speed, capable of displaying HD video in real time).
And the phone is more than just a mere computer -- it is a front end to the entire internet and all of the cloud infrastructure attached to it.
And we call it a phone.
[Answer]
Here are some historical names for computers thus far:
* Mechanism
* Machine / Universal Machine
* Computing Device
* Automatic electronic digital computer
* Electronic Numerical Integrator and Computer (ENIAC)
* Mainframe ("big iron")
* Personal Computer (PC)
* Laptop
* Server
* Tablet
* Smart Watch
* Cell Phone, Smartphone, now usually just "Phone" because older phones are becomes obsolete
* Device
* Cloud
* Wearables
I think the last few are most indicative of where names are heading. In recent years most people don't call computational devices "computers". In one sense computer networks have become very distant and ethereal, yet omnipresent... hence "**cloud**" becoming popular. I think this will remain a popular common name for the "out there" network.
On the other hand, computers are becoming integrated with our everyday devices, so we tend to just keep using **the original device's name**: phone, watch, glasses. Once computer shrink further, and cybernetics becomes common, I suspect that computers built into humans will just be called "eye", "arm", "heart", etc.
[Answer]
For once, philosophy comes in handy here. A philosopher/mathematician called Frege introduced the following formal ontology { concept, object, name }. Anyone who has programmed a computer using an object-oriented language will recognise this as { class, object, name }, where an object is a named instance of a class.
So we have the *concept* of computation, the *object* is the physical computer, the *name* is provided by the current social conventions - it may be "pc", "smart phone", "network server", or any other of a host of names given to computational devices.
Mathematics tells us that all computational devices are logically equivalent to what we call a Turing Machine.
The really interesting question is this : Is there anything in our reality which is not a computer? Our science seems to indicate that nature is inherently computational. We have lots of fancy equations that let us compute the outcome of events. We seem to be limited only by our ability to formalize the data around us. If this view is correct, then "tree" is another name we give to a computer.
[Answer]
What we call a thing is generally associated with it's original, or even primary, function.
As others have point out, a phone will always be a phone regardless of what other things it may do. The most basic feature of it is to make calls. Secondary features are playing games, browsing the web, keeping a calendar, etc. Interestingly, I overheard a conversation in which my 4 year old was telling my 3 year old that "telephones" don't exist anymore, they were replaced with "phones". He was very adamant that "they are NOT the same thing". This is as funny as it is true: we do tend to shorten names as time goes on, which can lead to future generations not really associating the "new" names with the "old" items.
Also, many many things now include a computer inside. Or, at least, some type of processing capability. Washing machines, fans, even high end chairs can be fitted with a processor to make them more "intelligent". Although they include parts which could arguably be used for more general computations, these are specific implementations in order to support the original function.
A desktop, laptop and tablet are all variations on the same thing. The form factor changed, but their function is to be a general computing device. Some are better at certain things than others, but they are all a general class of computing devices. Because of this, the name "computer" is unlikely to evolve in such a device regardless of form factor except, perhaps, to a shortened form. Maybe "comp" or "puter" or something along those lines.
Now if someone can successfully replace the form factor such that it's only the *interface* that matters (*ala Siri*) then we could very well see an evolution of the term to something radically different.
[Answer]
If another device took over from machines that were thought of as computers (e.g. tablets taking over the role of PCs) then a name derived from that might become a generic term for a computer. An alternative would be a brand name becoming a generic term for the item. For example, desktop computers used to be called microcomputers (or Micros) until the IBM Personal Computer got popular. Now PC has become a generic term for such machines.
[Answer]
I'm not sure computers in the future will be anything like what we have today so it won't be just a change in name. I think the most likely scenario is what appears in some of [Peter F. Hamilton](https://en.wikipedia.org/wiki/Peter_F._Hamilton)'s books - nanotechnology added directly to the brain to provide a direct interface. Using this technology is referred to as "datavising", but since it has no direct correlation with any device we currently have it's not really a renaming of the traditional computer.
[Answer]
In Warhammer 40,000, they're called cogitators. I think the word for them will *probably* remain the same, as long as this current culture continues to be more or less uninterrupted. If there is some major disruption, and then it changes to a completely different worldview, it might get a new name, otherwise it will probably just slowly evolve as language evolves, it will stay, most likely, with a translation of compute, computer, think, thinking machine, thinkmachine, cogitate, comprehendor, etc. etc. that same linguistic tree or whatever translation thereof in your chosen time period or culture.
[Answer]
One reason why it could get a new term is if another language than English became dominant, and that language's term would replace "computer". For example, the Chinese word for computer apparently is [diànnǎo](http://www.handedict.de/chinesisch_deutsch.php?deutsch=Computer) (the link is to an entry in a German-Chinese dictionary). So if Chinese should ever become the dominant language, the term "computer" might over time be replaced by "diannao".
The analogue happened in Germany, where the original German word "Rechner" got almost completely replaced by "Computer".
] |
[Question]
[
In my fantasy setting there are dwarves, inspired by the "stereotypes" and traits presented in [Dwarf Fortress](https://en.wikipedia.org/wiki/Dwarf_Fortress), and thus, partially inspired by the LotR lore.
It has the implications that dwarves use magic, but to an extreme extent, and even then, it's mostly for industrial usage of mining, refining, smelting, manufacturing and so on. My dwarves are practically on the brink of entering an industrialized era, rather being pre-industrialized like most traditional fantasy races.
Because of it, I started wondering, what inventions of the Industrial Revolution might be possibly practical to research, invent and manufacture for such a race, and the radio grabbed my attention.
For the record, my setting consists of multiple closed communities with varying tech level, from prehistoric to pre-WW1 era, meaning that the radio may already exist in this world. Thus, I can imagine dwarves obtaining a single radio, analyzing its mechanics, and replicating it.
My questions:
1) What preconditions are necessary for such a community to be able to invent the radio? Assume an abundance of any kind of metal, and that electricity is not widespread but they have proficiency with it.
2) What are the conditions necessary for mass-manufacturing early 20th century radios? Again, assume abundance of metal, proficiency in electronics, but also the existence of the concept of factories: assembly lines, separation of steps, etc.
Related question: what are the possible *obstacles* for such actions to happen? E.g. lack of fine mechanics
[Answer]
**Crystal radio.**
[](https://i.stack.imgur.com/Iw59N.jpg)
<https://www.wikiwand.com/en/Crystal_detector>
<https://en.wikipedia.org/wiki/Crystal_detector#Cat_whisker_detector>
>
> Patented by Braun and Pickard in 1906, this was the most common type of crystal detector, mainly used with galena but also other crystals. It consisted of a pea-size piece of crystalline mineral in a metal holder, with its surface touched by a fine metal wire or needle (the "cat whisker"). The contact between the tip of the wire and the surface of the crystal formed a crude unstable point-contact metal–semiconductor junction, forming a Schottky barrier diode...
> Only certain sites on the crystal surface functioned as rectifying junctions. The device was very sensitive to the exact geometry and pressure of contact between wire and crystal, and the contact could be disrupted by the slightest vibration. Therefore, a usable point of contact had to be found by trial and error before each use. The wire was suspended from a moveable arm and was dragged across the crystal face by the user until the device began functioning.In a crystal radio, the user would tune the radio to a strong local station if possible and then adjust the cat whisker until the station or radio noise (a static hissing noise) was heard in the radio's earphones. This required some skill and a lot of patience.
>
>
>
A cool thing about the crystal radio - it requires no energy inputs, but runs off the strength of the transmitted radio signal. Tesla's dream of broadcast energy come to life! The skill and patience part is perfect for dwarves and of course they would use flashier crystals. I envision radio rooms where large crystal rigs and similar geologic amplifiers allow the dwarves to listen to radio broadcasts from a distant civilization.
The dwarves do not know how to make their own radio broadcasts and see no particular reason to do so - the radio stations they get now have jazz and classical music better than anything the dwarves themselves can make.
[Answer]
Before you ask whether a society would be *able* to invent a technology, you first would need to investigate whether they have *a reason* to invent that technology. When a technology does not provide a tangible advantage, then it is unlikely to be developed, and if it does get developed nevertheless it is unlikely to stick around.
Most stereotypical Tolkienesque depictions of dwarves see them as living mostly underground. Radio is not a very useful communication medium for a subterran society, because rocks shield radio waves. If they need some form of real-time long-range communication, they would likely stick to mechanical or acoustic communication systems at first. When they electrify their society, then they will likely switch to telegraph wires and later telephone wires (still the standard for communication in modern underground mines). They are unlikely to develop radio technology unless they reached a level of technology where radio becomes a trivial side-product of other, more useful technologies.
...or if they have some pressing problem where radio technology could be a solution. Most of these problems I could think of would involve the surface. When a couple brave adventurers start surface expeditions, then radio could become a useful communication medium. Another possible use-case could be surface radio relays for communicating with far away settlements where tunnel connections are infeasible. A possible underground application could be short-range radio for communication within a very large and densely populated cave (I am thinking of walkie-talkies).
[Answer]
I have an ME (electrical) degree and 50+ years experience.
Give me 1900s technology and I can give you a radio system.
Give me Roman technology and 1900s knowledge and a cooperative patron and I can give you a radio system.
You need an energy source - batteries are "easy enough" but take cooperative resource.
You can have an electric motor based transmitter - and the Romans COULD have built them with their technology and 1900s (or quite a lot earlier) knowledge.
Copper wire. (Doesn't HAVE to be copper but it's doable).
A crystal detector material is useful but not essential.
Razor blade edge type detectors are doable.
Flame detectors if you must.
More details if it looks like people think the answer is useful.
You'd need to make a comment I'd see as I otherwise may not check back for a while.
**\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_**
People have queries how hard it would be to make a "detector diode" - known often as a 'coherer' in the early days of radio. Plain iron filings can be used. A flame can be used. A sharp edge such as a razor blade works, and a naturally occuring "Galena" (lead oxide) crystal, and quite a lot more.
Modern [Spark gap TX and Iron filing coherer RX](http://ashishrd.blogspot.com/2015/11/rediscovering-magic-of-wireless.html) |
---
From this highly informative webpage -
[THE COHERER AND OTHER
EARLY RADIO DETECTORS
THE DEVICES AND ELEMENTS THAT BEGAN OUR MODERN ELECTRONICS AGE](http://www.geojohn.org/Radios/MyRadios/Coherer/CohererMobile.html)
**De Forest Flame Coherer -**
[](https://i.stack.imgur.com/2ufMh.gif)De Forest flame coherer](<http://www.geojohn.org/Radios/MyRadios/Coherer/FlameDiode.gif>) and [**Many many coherers, receivers, ... here**](https://www.pinterest.nz/pin/643803709211899748/?lp=true)
[](https://i.stack.imgur.com/fin52.png)
[](https://i.stack.imgur.com/edAB8.png)
**\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_**
As a comparison of what COULD have been achieved with 'available technology" long ago.
As a parallel.
History tells us of Hero's Steam Engine - created by an Alexandrian.
A novelty / toy / diversion.
They COULD have ended up with steam catapults / chariots / ships / ... .
They didn't.
Wikipedia - [Hero's Steam Enine](https://wiki2.org/en/Aeolipile)
[Aeolipile images](https://www.google.com/search?q=heros+steam+engine&rlz=1C1CHBF_enNZ834NZ839&sxsrf=ACYBGNTcytfzNS8S58c26F5hXvYy5nxXBA:1571057524699&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiop7mt5ZvlAhUs6XMBHcHZAVUQ_AUIEigB&biw=3413&bih=1763&dpr=1.13)
[Answer]
Yes, with some difficulties. Especially if they could reverse-engineer an existing radio. There are [many ways to make simple radios](https://sci-toys.com/scitoys/scitoys/radio/radio.html), including using [three pennies](https://sci-toys.com/scitoys/scitoys/radio/three_penny/three_penny.html).
Normally there would be great difficulty in making *small* wires and diodes, but you say your dwarves are already proficient in electricity, which means they are already familiar with capacitors, diodes, and even magnets. The most complicated part of the items I've linked above would be the speaker (converting electricity to sound), but you can see the description of basic speakers [here](https://www.explainthatstuff.com/loudspeakers.html) and [here](http://www.physics.org/article-questions.asp?id=54).
With an understanding of - and ability to use - electricity, a race with plentiful metal and proficiency in simple manufacturing could definitely make a radio.
The question of mass production, however, is a bit more complicated. It is quite *tedious* to make reasonably-sized radios (ie radios you can carry) because the components have to be so small. It is unlikely to be able to produce *small* components without the use of machinery.
That said, sticking with larger, 1800s-era "simple" radios, mass manufacturing could be done assembly-line style. Note, however, that this is not easy to be done *at once*: there will need to be mining, then creation of the components (wire, baseboard, magnets) as a second step (metal takes time to cool). Then transport those components to a location where dwarves solder and assemble the pieces together.
Note that the complexities here are (a) organizing many dwarves from many different areas (mining, metalworking, assembly lines) to cooperate, (b) finding a fair way to balance the wages and values of each step, and (c) convincing all these dwarves to participate. In other words, it's a large *organizational* undertaking, which is why capitalistic societies tended to mass manufacture first; these types of things involve so many moving pieces in so many areas. I'm not saying is *has* to be a capitalistic society, only that the organization capacity and cooperative ability of the dwarves would *definitely* be a limiting factor.
[Answer]
Sorry, you can disregard this. I just reread the original post more carefully and I see that your dwarves have a tech level at the beginning of industry. It's someone else who has a tech level closer to WWI.
---
If you're asking what I think you're asking, the answer is yes. I think you're asking if a society can invent a radio before having World War I technology. In real life, the radio was invented in 1895 so that's not a problem. The fact that these people are a little shorter and wider on average than we are is irrelevant.
If you're asking whether they could have more advanced than we did in 1913 while still having broadly pre-World War I technology, then I'd say yes. Different technologies aren't guaranteed to advance at the same pace. It's possible to have a society who's radio technology is a little ahead of where ours was while being a little behind ours in a few other ways. Maybe they haven't invented airplanes or cars but their electronics are advanced.
] |
[Question]
[
Assuming a world otherwise like ours and at the same technological level of medieval Europe, what change in the world might have caused people to build defensive structures underground rather than above ground?
I've already thought about riding large flying creatures, and dragons are far too obvious. What else might cause this?
[Answer]
The short answer is nothing. The offensive and defensive aspects of war tend to evolve in a leap frog fashion in much the same way that any two directly opposing forces do. Without a threat to necessitate the development of underground defenses there wasn't much drive to create them.
The best defense at the time was high walls, gave archers better range and line of sight, and it made it harder for attackers to get through. In the end defense are there to keep you protected and applying force as long as possible before the enemy is upon you. If I think about warfare at the time, underground defenses actually seem like a worse idea than what medieval Europe actually had, for example fire was a commonly used weapon...underground + fire = bad.
A fictional threat would be the only thing I can think of that would necessitate the creation of underground defenses in medieval Europe...more to the point, without that threat they would actually be less effective in medieval combat when compared to castles, towers and walls.
* Flying creatures of some kind are the obvious choice; dragons, wyverns, maybe some giant Rocs.
* I suppose you could go with some sort of really large land animal, I am thinking of the elephant/hammer head shark crossover from Avatar.
* Giants. Really really big giants.
* A magic system where the earth somehow negates powers...
Now, even with these creatures in the world they would have to be common enough that they showed up in a good portion of battles, otherwise, when its just human on human fighting castles would still be the way to go. Castle building/defense in this scenario would, I think, be mainly for hiding as opposed to castles traditionally being bastions from which to exert your local authority.
*edit:* Thought about this some more, and no matter what else a castle needs to allow you to fight back otherwise it is just a tomb, doing this on a flatland...I don't see that working out well for the defenders. If the castle is underground...returning fire would be pretty tough, unless its built into the side of a mountain or under a hill...like this.
So in this image, you could have an underground castle with tunnels up to the surface, if your enemies are dragons, their are trapdoors with ballista, or maybe a good old fashioned death trap for a giant (big spikes at the bottom of a hole). I still think a flying enemy makes the most sense and when I think of underground fortresses I do feel like its more hiding than just purely defensive like a castle.
[Answer]
Medieval Europe had a greater dependency on existing features of the land than we do now. Cities often grew up around rivers and fortresses were built on existing hills.
If the ground was riddled with natural caves and tunnels then large cities were established underground, such as those at Derinkuyu and Özkonak. These date from 500-1000AD, they housed tens of thousands of people (very large for the time), and they were well fortified.
If you're looking for a change that forces *every* fortification underground, why not make natural underground features much more common? If living underground is the social norm, and naturally defensible features such as hills and rivers have useful underground features then the fortresses will naturally be constructed mostly underground.
[Answer]
A climate far to harsh to stay on the surface for any length of time.
* Powerful winds coupled with sand would quickly damage clothes and skin.
* Highly acidic rain could melt skin. (verify this)
* Irradiated (not necessarily deliberately) land could drive people underground as the earth would provide protection.
* To borrow from Stargate, a lack of an o-zone layer could quickly burn people, causing cancers and such.
* Lots of rain/low-lying land would cause flooding. I believe spending lots of time submerged can cause various health issues on its own.
* Cold. If the winters are so cold as to often cause death, I image people would've gone underground for warmth's sake.
EDIT: These ideas don't stop people going on the surface necessarily. Just not for too long.
[Answer]
What about [hot-air balloons](https://en.wikipedia.org/wiki/Balloon_%28aeronautics%29) or zeppelins? They have been inserted into middle age with success in some stories taking place in the middle ages.
They are a big advantage for attackers (if they manage to navigate over the enemy place), and would allow them to "jump over the walls" (thus justifying your underground structures), but at the same time they do not require a really advanced technology, and is not too unbalanced since they could be knocked down by an archer (specially dangerous if the arrow is in fire\*)
Air-transport would also make inefficient walls guarding a territory. such the Great Wall (just fly over them) or castles in the middle of the way. This will mainly depend if provisions can also be transported that way or they need a traditional ground convoy. Also if there is a way for defensive balloons from the castle to intercept the attacker ones (can they block another balloon, or only move in the same direction imposed by the wind?).
\* The balloon will explode, additionally putting in danger other attacking balloons.
[Answer]
In Anne McCafferey's Pern books, humans retreated into underground cities to escape Thread, which was an organism like a highly corrosive string that fell from the sky from a rogue eccentric planet for 50 years each 250 years. Since it would devour animals and vegetation, but not stone, people had to live in stone dwellings. Of course, the dragons in the series helped make sure that thread didn't fall to ground, but they weren't infallible, hence underground cities.
[Answer]
If the planet habitually flew through a light meteor shower. These would need to be bad enough to cause light destruction and kill the odd person, thereby necessitating the building of underground defensive structure much like air raid shelters.
However they would need to be not severe enough to do major structural damage to the society that might impede technological advancement of the civilization.
[Answer]
I'd venture to suggest that the tunnel systems used by the Japanese during the battle of Iwo Jima would be a viable tactic in a medieval setting against a force vastly superior in numbers & equipped with such siege engines (including cannon, mortar, bombards etc) as would render a castle little more than an expensive trap for the occupants.
Where you have a small number of defenders equipped with ranged weapons (such as bows or crossbows) or who wish to make harrying attacks on the enemy in a highly mobile fashion, popping up in unexpected places & vanishing having ambushed the enemy, an extensive tunnel network would be very useful indeed.
* Maybe the defenders are few in number because their country has been
ravaged by plague?
* Maybe they're the descendants of a once-great
culture who were able to dig these tunnels. They might be catacombs -
an extensive tomb network full of treasure the defenders wish to
guard against the invading infidels.
All kinds of possibilities, really.
[Answer]
Underground defensive structures can be an outgrowth of escape tunnels (for example, while facing a large invasion army while having a very small army on your side). Even with small or no changes to how physics works, people would still use and develop technology along existing lines of development - so, for instance, if people used to make overground structures, but some warlord employed technology and strategies taking advantage of their weaknesses so severely that they became useless, forcing people underground, it could explain why you'd see a lot of them around. If others imitate the same methods and technology (very likely if they don't have the time or means to come up with better ideas or the application of other methods doesn't catch on enough, considering underground structures are the target now) it's likely that you'd see widespread use of underground defenses, possibly even adaptations and structures not employed in real life due to lack of need (no need for us to have ways to mitigate liquids poured into shafts or vibration siege mechanisms in the 14th century) - we'd come up with sewage systems and flushing toilets sooner I suppose.
They could also be a side-effect of landscape features or lifestyle. If there's a *lot* of sharp elevation changes and/or a strong need or adaptation to mineral and metal use, chances are lots of people would want to stay closer to their work or prefer tunneling into a mountainside instead of building a castle on a slope at a large angle. *Obviously, a large mining colony underground would require safeguards to not die from fumes and dust, but people are resourceful enough in fantasy settings :P*
[Answer]
Not really suitable for a mediaeval fantasy genre, but a lot of Moonbase scenarios involve burying pressurized shelters under regolith. Large quantities of dirt and rock can make an excellent radiation shield. This could be seen as a variation on "blistering heat on the surface." Just a different definition of HOT!
The weight of soil and rock could be a hazard in itself. On the other hand, a properly designed shelter could be less sensitive to blowouts when buried. One assumes the shelter would be properly designed…
[Answer]
because of:
# The Red Eye
My suggestion, entirely fantasy based:
Everyday at night (twice a year on eclipses) the moon of -insert name here- rises in the sky and basks the land in a red light. All land animals become agressive after a few minutes of full exposure.
The red light comes from a distant sun directly opposed to the main sun. Its light reflects on the moon and turns the night a dark blood red color. On the other planet side, the daylight from the main sun cancels the influence of the red sun.
The red sun isnt visible during the day, but sometimes the moon has a pale salmon color.
It doesnt affect water animals, as they´re not directly exposed to the same amounts of the red light.
All land animals that hunt at night and get exposed become agressive, somewhat rabid like for a few hours.
The red light does affect humans, and more agressively as they dont have hides. The usage of thick cloth is required. Also, many live underground, as it is common knowledge that it is the best place to shelter from the evil influence od the red eye.
So, many children stories warn about the dangers and the monsters after dark.
Also, on eclipses, the moon blocks the main sunlight and reflects a lot of the red sun light, the influence peaks at this moments and these are days to be feared.
Dont crucify me on lack of astronomic details or such, I´m just trying to present a new view for the question (They only need to live underground during the night).
[Answer]
**Hail**
Even in modern times hail can cause substantial damage to buildings and automobiles. If something happened to cause frequent storms with baseball or larger size hail, building underground shelters could easily become the de facto solution. It would be easier than lifting and supporting huge sheets of stone.
**Advanced/Giant Catapults**
A mobile war machine that can rain giant chunks of stone down would also necessitate heavy overhead protection.
**Pacifism**
Castles may be defensible, but they are also obvious. If the city in question was more interested in hiding than fighting back, going underground is the more obvious choice.
[Answer]
Underground defenses or building did, in fact, exist in Medieval times.
This was because underground offensives existed. If you couldn't get over a wall, you'd tunnel under it. You started your tunnel out of sight of the people behind the wall, because then they would make a counter tunnel to prevent it.
Tunnels were dug in order to take down walls, you'd tunnel underneath a wall to weaken it, allowing your army through. The counter tunnels were dug to meet them before they could, and kill all the men in the tunnels.
If it happened often enough, some castles had lots of tunnels under them, already built and shored up so that they would be ready to meet the offensive tunnels, and if the enemy got in the defensive tunnels, they would be met by soldiers.
There are other reasons for underground building. Storage. And protection from the weather. Abbeys would often build them, just to stay out of the harsh winter.
Everyone else on here had had some excellent ideas for forcing things under (natural features, outdoor problems) but just wanted to point out that underground defenses did exist back then and the reason.
[Answer]
[[[https://en.wikipedia.org/wiki/Derinkuyu\_underground\_city][1]](https://en.wikipedia.org/wiki/Derinkuyu_underground_city)
and <https://en.wikipedia.org/wiki/Kaymakli_Underground_City]>[2](https://en.wikipedia.org/wiki/Kaymakli_Underground_City)
are you best examples, built when the ground made it easy and periodic raides were the problem not large scale military incursion. The big benefit it is is really hard to break in. they used a giant stone wheel they could just roll over the narrow entrance from the inside, and there was basically no way through it short of spending months with chisels. great for places with little to no military. In the desert underground is also a lot cooler during the day and warmer at night. of course they had buildings above ground as well.
if you have big flying dragons, this would be perfect defense for villages and towns, there is no way for the dragon to get in, just too big, and you can hide the livestock inside as long as you have stored food. larger cities would probably build strong buildings, but you might be able to justify it if the threat is older than the cities, and dig down was already how they dealt with the threat. they might never have considered other options.
[Answer]
## Helium balloons as bombers
Your alternate world would need to have easily available helium, that's all.
People will figure out how to make a balloon quickly (without the need for electrolysis or other hard tricks to obtain a light gas). The invading army just needs to wait a couple of days and once the wind is good, they launch bomber balloons. The bombing goes at about 200-300 meters altitude, so it is hyper-precise even with the most rudimentary bombsights. No optics needed from such a distance. There is no active defense possible with medieval weapons.
The **city walls** don't make sense, they take decades to build but a breach could be made with just one gunpowder bomb. Just a single one-man balloon with a single 100-200 kg bomb can open the way for a regiment of infantry.
You need **underground bunkers** for military and large shelter systems for civilians. You can release the infantry anyway when enemy infantry is at melee range or when a last balloon passes. **Archers** can shoot from within the bunkers.
The defense forces could use **cavalry** a lot: it doesn't need to go to the shelter at all, because it could outmaneuver balloons with ease.
You need helium **not hydrogen**, because the balloons need to carry an open fire for those gunpowder bombs.
] |
[Question]
[
I'm currently writing a story set in a post apocalypse. It would be based in the current year . This story takes place from the perspective on one person who is speaking to a group of people, all in separate locations. Their main form of communication is radio. As far as I can remember any time I've seen characters use radio communication in any form of media it would always be a situation where only one person could talk at a time. So I wanted to know if there are any radio devices, or any other devices that could be easily attainable by the average person, relative to the setting, that would allow multiple people to speak simultaneous in a post apocalyptic setting.
[Answer]
A simple 2 way radio only works when one person is talking at once. Modern technology has given us many ways to work around this limitation, at the cost of added complexity unnecessary for simple 2 way voice communication.
Similar to how it's difficult to hear someone talking when you're also talking, sending and receiving on the same channel, at once, doesn't work well. On a simple 2 way radio operating on one channel, any station that starts transmitting while the channel is in use will obstruct communications. This is why radio operators follow established [voice procedures](https://en.wikipedia.org/wiki/Radiotelephony_procedure) to coordinate who is speaking when on a single channel. If your group of survivors are having one conversation, then by taking turns talking, similar to how they would communicate if speaking in person, they can all use a single channel at the same time.
Of course being crafty monkeys, humans have come up with all sorts of creative techniques for working around this restriction. A simple one being duplexed communication. By using 2 channels one for sending and one for receiving, it's possible to have simultaneous 2-way communication. We've also come up with many ways to smoosh more operators into the same channel, using complicated encodings, and transmission strategies.
If you're old enough to remember when cell phones started being popular, before they became primarily devices for accessing the internet, that used a more complex system to enable multiple devices sending and receiving data on a single channel simultaneously. [Code Division Multiple Access](https://en.wikipedia.org/wiki/Code-division_multiple_access) uses some fancy math to be able to extract single signals from many on a single channel. [Wendover Productions](https://www.youtube.com/watch?v=0faCad2kKeg) has a great explainer should you want to know more of the details. While CDMA and more advanced technologies can allow for large numbers of people to share the same channel at the same time, this requires dedicated technology like cell phones and towers which it seems like your survivors don't have access to.
[Answer]
This is how the good ol' radio ([amplitude modulation](https://en.wikipedia.org/wiki/Amplitude_modulation)) works. If everyone broadcasts on the same frequency, everyone hears everyone else. But you cannot broadcast *while* listening, you would overwhelm (and possibly destroy) your receiving tuner (amplifier). Simple solution would be automatic voice (sound) detection - while you are speaking, you are broadcasting, but as soon as you take a breath, you can hear everyone else. This is already complicated, but still early vacuum tube technology.
With technology, this becomes more difficult - [FM](https://en.wikipedia.org/wiki/Frequency_modulation) exhibits capture effect, you will hear only the strongest sender. And with digital, everything unexpected is noise (unless carefully designed otherwise).
For this reasons, amplitude modulation [is still used](https://en.wikipedia.org/wiki/Airband) in aviation - if two pilots ([or the control tower](https://en.wikipedia.org/wiki/Air_traffic_control)) speak at the same time, you at least know they want to say something (and can ask to repeat etc...) as opposed to
not knowing someone wants to communicate.
And that is a solution for your post apocalyptic settings - your parties got hold of a bunch of aircraft VHF radios. Perhaps raided a [cemetery](https://en.wikipedia.org/wiki/Aircraft_boneyard) or a former busy airport. The radios are in perfectly working order, just hook them to the power (and an antenna) and there you go (you do not even need a surviving ham to help you, just some basic competency with electricity and some experimenting).
[Answer]
There is a very good reason that radio is usually one-person-talks. If both people have their microphone open at the same time as they are receiving, then you get feedback.
Headphone warning. This vid at this link has high pitched squealing noises on it.
<https://www.youtube.com/watch?v=82scBZ3h62Q>
This results as follows. A small sound is picked up by the microphone and amplified. The speakers put out a louder version of the sound. This louder sound is picked up by the microphone, and amplified again. And around and around.
With two radios this simply means the loop involves two microphones and two speakers. A sound is picked up by one microphone and transmitted to the other radio and amplified. It is then picked up by the other microphone and transmitted back.
There are two main ways of reducing this.
One is directional microphones that pick up sound only from sources directly in front of them. This allows you to do such things as have a person at the front of an auditorium speak into one microphone, and another person in the audience asking a question into a second microphone. You can still get feedback. To avoid it the audience mic is usually fixed in place. There will also often be clever speaker placement so that the speakers point at the audience not the microphone's pickup location.
The other possibility is headphones. That way the available sound is kept very much lower in volume, and microphones tend not to pick up enough sound to produce feedback. It may not be convenient to make everybody use headphones.
[Answer]
**Simultaneous transmission is how radio works. The button is there for economy and convenience.**
There's nothing stopping simultaneous transmission on any radio frequency. The one-way communication you're accustomed to seeing exists for two reasons.
1. Some radio systems use the speaker as a microphone. Speakers are like generators/motors, whether or not it's a microphone depends on how it's hooked up. Attach an active signal circuit to it and you get a speaker. Attach a detector circuit to it and it's a microphone. Using the speaker as a microphone is cost effective, especially in units where the quality of the signal is less important.
2. More importantly, most radio has mediocre fidelity. You can get around this (concert-quality music can be transmitted via radio), but it doesn't change the fact that unless you have a complex microphone setup, the audio is *flat.* There's no dimension (there are some really cool tricks game designers use to give game sound a sense of direction and depth — but you don't have that in most radio broadcasts). As a result, when multiple voices are overspeaking on the frequency, it's very difficult for the listener to distinguish the speakers.
*Don't under-estimate what your ears and brain can do. It's amazing. In the 3-D space your two ears and fearsome brain occupy you can easily distinguish unique voices in a room full of chatting party-goers. But all the indicators your ears and brain use to do that don't exist on broadcast radio. Using radio, unless you have a complex speaker setup, all the sound is coming from a single point in space with.*
And to make matters worse, it's whompingly hard to filter *your voice* out of the conversation. So if simultaneous transmission is occurring, you're hearing your voice along with everyone else.
**But is that really a problem?**
Heck, no! Do a little research into [party line](https://en.wikipedia.org/wiki/Party_line_(telephony)) telephony. Rather than a single line running to your house, your very one telephone line that could connect to anyone else, a party line was a loop that had multiple people attached to it — all chatting away like there was no tomorrow never mind how many conversations where happening all at once.
In other words, we've forced radio to non-simultaneous transmission for the same reasons we've left party lines behind: privacy and convenience. Nothing more.
If you want simultaneous transmission, you've got it. We actually go to an extra effort to stop that.
---
**Edit:** Some folks have really missed the point. Imagine a conference call on your cell phone. Three or more people talking simultaneously over radio. You don't even need a conference call. Put both cellphones on speaker phone and a dozen people can chat away just fine. There's nothing magically different between MHz and Ghz carrier frequencies. If there is a difference, it's that digital signal transmission is simpler because signal discrimination is normalized and packet identification is easier to deal with than separating modulations. Independent branch circuits for the microphone and speaker are also much simpler — but they're not required. Even the receiving and transmitting events (which occur at different power levels) can be done simultaneously with the right circuitry — it's just cheaper and easier to separate the circuits. But we live today in a world filled with simultaneous radio communication. We have done for quite a long time now.
[Answer]
While there are multiple convenient solutions, like the one your phone uses, **the *simplest* solution works with even the earliest radio technology: have everyone use different frequencies for transmission.**
This can't scale to thousands of transmitters in the same area - there are not enough sufficiently apart frequency bands. But a few dozen people could speak at will into their fixed-frequency transmitters.
As a caveat, you'll need a separate receiver for each person you'll be simultaneously listening to. (Good engineering could reuse *some* parts, but only some parts, and then we're no longer talking about the earliest radio technologies.) Such costs would be dear in any respectable post-apocalypse scenario. One could add a relay station to mitigate this. The relay station mixes all signals there. Everyone else just needs one transmitter (on his own frequency) and one receiver for the mixed signal sent by the relay.
Another caveat: interference and propagation limits works a little differently at different frequencies, so its effect would be selective.
[Answer]
Experienced **radio telegraph** operators are entirely capable of simultaneously sending a message with one hand and receiving and writing down a different message with their other hand. This might be close enough to 'talking' for your purposes.
[Answer]
Don't forget that cell phones use radio waves to work.
It is feasible to have your own personal cell tower. Depending on where you live these cost like a thousand US dollars. There are more expensive options that are mobile, called C.O.W.'s (cell on wheels). With one such tower around, you can use telephones instead of walkie-talkies. Also you don't need smartphones, any dumbphone will do as long as it is not something pre-historic. Even those old, indestructible Nokias should support group call.
A GSM cell tower can cover anywhere from 3 to 80 km (~2 to 50 miles) depending on its power rating and how it is set.
[Answer]
The term you are looking for is full-duplex. Push to talk systems like most hand held radios are half-duplex where only one person can talk at a time. For full duplex communication (such as is used in cellular networks) you typically need a separate resource for transmit and receive. The most straight forward method is to have different frequencies for transmit and receive, but it can also be done with very short time slices that people don't notice, or with more advanced coding mechanisms.
<https://en.wikipedia.org/wiki/Duplex_(telecommunications)>
[Answer]
How far past apocalypse is the setting and how long distances there are?
For relatively short distances WLAN and various levels of networks can allow this. Just need enough power to be around. And someone skilled enough to configure the network to work. With somewhat better organised societies even long distances might be possible as long as hardware continues to work.
Packet networks(like Internet and WLAN) where data is transmitted to both directions at same time in small chunks or alternating really fast do exactly seemingly simultaneous talking. Just need working network(some routers, some solar panels and some batteries) and right software. The software can be run on your average laptop, tablet or smartphone.
Most of this can likely be scavenged unless the apocalypse was type of frying all electronics, in that case all bets with radio are mostly off anyway. With simple population reduction, there is likely enough gear around for a years to decade or two.
[Answer]
HAM Radio operators do this all the time. We can certainly hear and understand multiple people talking at the same time.
If we are operating with only one antenna, then when we transmit we don't hear the other voices until we stop transmitting. But, many transceivers can have more than one antenna attached and even accommodate a transmitting antenna versus a receiving antenna. Or, we simply run two transceivers each with their own antenna. Using two rigs allows us to transmit and receive simultaneously - even on the same frequency.
Of course, it is easy to establish a convention where you transmit on one frequency and receive on a frequency just slightly higher or lower on the dial. We call this using an offset and helps to divide the cacophony of voices.
These are all techniques we use today.
[Answer]
This is actually a common problem that had to be solved for modern video chat services. The way they do it is basically the time-sequenced digital transmissions (a.k.a., packets) that all go to a central server for combining and rebroadcast as a unified wave form.
The problem with multiple people talking on a single frequency at the same time is that your radio will only pick up the "loudest" signal. That's almost always your own. This is how radio jammers work: they broadcast a much louder signal that drowns out all of the other signals.
For small areas (like a few blocks), you could use existing mesh network technology to collect and combine multiple signals. If you're talking about uncoordinated groups, like refugees who don't know who you are, then this isn't a thing. It requires coordination.
] |
[Question]
[
My character has stumbled upon another planet with life, and they are able to walk on walls and ceiling, completely ignoring regular gravity (by magic, science, whatever, it doesn't matter all that much). My question is, how would the layouts of the houses change?
I'm guessing that the water appliances would be on the ground(sinks, toilets, fridge) since they are still effected by gravity normally. When these people walk on the walls, they still feel like they are standing normally (kinda like Monument Valley, I guess), so if they are on the ceiling, they feel fine. Furniture can be mounted to the walls/ceiling by hooks and extra strength fasteners, so those can be placed anywhere.
I know this is kinda vague, but I'm still figuring out what kind of rules their gravity works by. Like, if you're holding a coffee on the ceiling, does it fall ten feet to the floor or just sit in the cup normally. Lots of little details to smooth out.
[Answer]
Not much. We don't use walls (as floors) not because we can't walk on them. We don't use them because whatever is there interrupts what you are doing on "main surface". You ever hit your head on a shelf? Now you hit it even more because there are other things on the wall. Hit your toe on a nightstand? Now you hit your arm, shoulder, hands.
Everything on a wall casts a "shadow". That's why the most usable and space efficient are cabinets from floor to ceiling. And there wouldn't be even much change in those are humans put in the "middle" things that have a lot of use. Going down and up the use of things stored fall. Having ability to reach from ceiling would just expand the "usable zone".
Remember that putting stuff on the ceiling would mean that whole place must get higher (for example I very often hit my head on lamps in places where height impaired people live). And of course everything would need to be illuminated in a different way. Having a one light source at the ceiling is energy efficient. Any obstruction would cast a real shadow. So another lamp. Or glowing things.
In communist countries there was a thing called [Pawlacz](https://pl.wikipedia.org/wiki/Pawlacz) A storage for things that you don't use very often but often enough you don't store them in basement or garage.
So having a whole ceiling that could act as a storage could have some usage. Kind of like a dropped ceiling.
[Answer]
For multistory buildings, you can substitute treadmills for elevators and escalators. They will occupy less space, use less power and might even be more comfortable and faster. On top of that you can walk on them to add your speed to theirs. It would be much like the treadmills you see in modern airports, only vertical. You also don't need stairs.
Since walls and the ceiling are now usable, social space, illumination gets more varied and looking more like floor lamps.
But the biggest impact is how much useful space you have. If you consider a cubic house that is $x$ meters/feet long, for humans on Earth you have $x$ m2/ft2 for a layout - but for such creatures in their homes the same house shape would mean 6$x$ m2/ft2 for home modeling (floor + 4 walls + ceiling). You can fit a lot more stuff in it. You could have a living room on the floor and a home theater on the ceiling, for example.
[Answer]
Walking on walls doesn't make that much difference. Everything else still fall down. Shelves, cupboards and bookcases are still the same and will will take up every available vertical surface.
Along with windows. What happens when you step on one? Does it had to bear all your weight? If so, you've got lots of serious hazards. It would not be safe to talk on a surface littered with such traps.
You can stand on the ceiling, but your coffee still falls towards the ground. You have to hold your cup upside down; drinking might be difficult and messy.
It gives you slightly more space, but only slightly. People on different surfaces are still going to get in each other's way,and bump into furniture on other surfaces.
With high ceilings you could use the extra floor space for dance floors, exercise room, meeting space or anything that does not require any small objects -- because anything not velcroed down will fall to the floor. The limitations mean that it may be more like having access to an outside space (eg a flat rooftop) than additional living room as such.
[Answer]
**Larger rooms, smaller houses**
The rooms will most likely be shaped in a way that 2 sides are close enough you can walk with little danger of hitting furniture and possibly each other. The sides will be used for walking and one side might be more heavy with electricity and water, although it might be inside the side. One side might actually not be used for walking, as requiring to have a person's lenght worth of distance without furniture on every side would be wasteful. I say sides, as the box can be flipped any way you like. Further floors can be reached by how you would normally walk to your bedroom, only via a side. This makes a volume more efficient, making it possible for houses to be smaller with more stuff.
A larger box can also be used. This means 6 sides are useful. It will create a large empty space in the middle. If your box is big enough, you can add another plateau in the middle for more usable space. You can always walk there anyway, as you have at least a walkway to it.
Lighting would probably go to light strips in the corners. This way you have more equal lighting throughout the room. With the box where you mostly use 2 sides for furniture you can add a lighting rig that lights each side independently.
Heat would be just the same, only you have a warm ceiling, so in winter you would be there more often. Heat differences would be much higher, so heating might be more like floor heating, that heats the room more equally.
[Answer]
It may seem obvious, but a big difference would be
### No stairs
In every house apart from bungalows, you need stairs to get to the next floor. Stairs occupy significant floor space and volume, because the stairs cover a similar area on both floors. Spiral stairs are sometimes used where space is very limited, but they have serious limitations (try carrying anything heavy or bulky up them!) so are not popular.
If you can walk on walls though, you don't need stairs. A "lift shaft" from the ground floor to the top floor will be perfectly adequate for people to walk up and down, saving space which can be reclaimed for rooms.
[Answer]
I think rooms would often be shaped like hexagonal prisms, like honeycombs in a beehive. A 90 degree transition seems like it would be annoying and disruptive even with magic, and it'd confuse the senses.
The transitions in a hexagon are much more manageable, enough that a person could probably run a circle around the walls like it was a giant hamster wheel. A circular room would be great for a gymnasium though, good place for a running track
You could do something more exotic like a building made up of 3D tessellating polyhedrons, but the honeycomb shape seems more practical, buildable, and would preserve the convenience of rooms having a large flat surface (well, two of them in this case)
[Answer]
First off, I think houses certainly wouldn't have to be as big, as space would be more efficiently managed, but you'd have to be careful where furniture is placed so you don't have to constantly dodge it while on another plane. Having vertical as well as horizontal divisions would also certainly make for some funky house shapes, and houses might be built in height more often than not.
In terms of lighting maybe a chandelier-type light that hangs smack in the center of the room (imagining a room as a cube) and casts light in all directions might be an interesting way to go about it - with just one light switch you could illuminate 4 planes/divisions.
I'm not sure how the stepping 90 degrees into a vertical plane would work, but rounded house corners might be a thing, provided you want to reduce the strain on your joints when you do it. Not sure how relevant this is though, given that they seem to defy other laws of gravity.
[Answer]
## The Structural Integrity and Materials of Walls and Ceilings Would Require a Higher Standard
This was one of my childhood fantasies - to be able to walk around on the ceiling. Then it occurred to me, gazing up at the removable tiling and the thin plastic covers of the fluorescent lights on the ceilings at school; there was no way any of that would bear my weight. And at home, lying on the top bunk and putting my hands and feet on the spackled plaster ceilings, I could tell that they, too, wouldn't bear my whole weight - to say nothing of the havoc my shoes (or feet) would work on the spackle, or how uncomfortable it would be to walk on. And nobody is going to use sheet rock to make walls, if it's expected to bear foot traffic!
Even brick or stone or concrete walls, even sheet-metal roofs, are not designed to bear people's weight anywhere, at any angle, all across their surfaces!
The engineering questions regarding the walls in your living room would be very different if each wall was expected to have the same maximum weight tolerance as the floor. If you also want to, additionally, hang or otherwise attach pieces of heavy furniture on a wall (like a large couch, which can be nearly as heavy as a compact car), you need the wall to have materials which will bear pulling at various angles, not just "pushing" by the occupant's new definition of down.
Sure, there would be layout differences purely for convenience. I can imagine large rooms as having interesting columns or other vertical surfaces in the middle, as additional pathways to the ceiling. But setting aside any convenience questions, or different layouts... The impact on engineering and materials required to build buildings which not only keep out the elements, but bear the weight of (multiple) adult people in almost any direction on any surface...
"Timmy, this is not an expensive house. You can't have both of your friends with you up on the ceiling at the same time. Someone has to come down, or I'll make you all come down."
A lot of things you take for granted would have to change.
[Answer]
Not much would change about the inside of the house - as other answerers have said, objects on the ceiling are still affected by gravity, and you can't just furnish another room on the ceiling even with proper mounting because of clearance issues. Sometimes you might see slightly taller rooms intended to be used both the right way up and upside-down, but if you have the means it's much easier to just add another floor and avoid the hassle. Especially since a simple door in the ceiling/floor is enough to move between the upper and lower floors.
On the other hand, the place would need to be much better secured on the outside. Any walls or fences you build around the house will be completely ineffective in warding off intruders unless you put barbed wire or other deterrents on them. Living on a higher floor of an apartment building no longer means you're safe from someone breaking your window. The roof of your house is accessible from the outside just as easily as it is from the inside, and so on.
[Answer]
The model in my mind is Dracula in the film Van-Helsing (with Hugh Jackman)
Aside from general vampirism, he can stroll casually up walls and end up on the ceiling. This doesn't affect anything he's holding, even his hair follows normal gravity to some degree.
The fact that gravity still affects any objects aside from the people is a major factor.
The walls are impractical for most purposes, things will fall sideways, you can't really eat, drink or put objects down without special care.
The ceiling is much the same.
So while you might be able to sleep in a bed on the ceiling, you can't really do anything else you'd want to do day-to-day, even your wardrobe won't be convenient to use in your upside-down bedroom.
So the walls and ceiling are most useful as a route to more conventional rooms.
You might see fewer houses with stairs, but there are advantages to stairs anyway.
Imagine trying to carry a tray or box of loose objects underneath your forearms when you're on the ceiling!
Human physiology is not really well suited to carrying objects under such conditions.
I imagine houses would be built mostly conventionally, rooms stacked on rooms. But in some cases, you'd take advantage of the wall-walking to traverse up, over and around into more private areas that can only be reached by wall-walking.
[Answer]
>
> Like, if you're holding a coffee on the ceiling, does it fall ten feet to the floor or just sit in the cup normally. Lots of little details to smooth out.
>
>
>
Sorry, but you've got more than little details to smooth out.
As soon as one way of movement can ignore some of the existing energy constraints (walking on walls ignores gravity), you have to take care, or you get *perpetuum mobile*, aka infinite energy, rearing its ugly head.
Make a high frame, one side of which is a slick metal wall. Take a big block of something heavy. Attach it to some railing on frame corners, so it is stable. Add some pulleys etc, and let it fall slowly to ground. That will generate you some energy in pulleys that you can easily convert to electricity. Then, instead of lifting it back, **push** it along the wall. Make the block be as slippery as possible to minimize friction. In fact, there are ways now, that claim to [reduce friction to almost zero on macroscopic levels](https://phys.org/news/2015-05-method-friction-surfaces-macroscopic-scale.html), but it even needn't be that bad. It is very possible to push even normal heavy loads across floor that you can't lift, showing that pushing uses way less energy than lifting.
[](https://i.stack.imgur.com/c0rGS.png)
Blam, you got energy. If energy of pushing < energy gained during fall, you get an energy surplus during fall = free energy. If you need human to push it, it might not be that bad. Otherwise you can just store that fall energy in a spring or something and make the push happen automatically. Probably will still get more energy out than you put in.
In fact, [storing gravity energy is a thing](https://heindl-energy.com/technical-concept/), with a number of attempts currently in the world. And that is even without having the luxury of lifting the weight without gravity.
What happens in worlds with infinite energy is debateable. However, as soon as there is too much energy in something, it tends to explode. There are several questions here on WB about that.
As an afterthought, if people can walk on vertical surfaces, you gotta redesign security. Upper floor windows are now not safer than 1st floor. Mountain ranges are strolls in the park. What about cars? Do cars with peoiple in them can drive on walls too? There are tons of questions and on almost every aspect the world is very weird indeed.
[Answer]
I'd say houses would be a lot smaller. With 4 walls, every surface can be used, instead of just the floor. I'd also say that every room would be divided into 8 cubical rooms, one in each corner, with one corridor in the each of the x-y-z axes. Doors would be odd; I'd expect each would be a trapdoor that opens either way, with latches holding the trapdoors open. I would also say that the main entrance would be at floor level, since the surface of the planet is the same, and that the floor would store small objects that are susceptible to gravity. Heavy objects would be placed on the floor due to the danger of them falling. Ceiling fans would be banned due to their safety hazard. There may also be "pull-up bars" that you'd jump to, grab, and then use to swing yourself to the ceiling without having to walk to and up a wall. Finally, I'd say that ceilings and walls would have to be stronger due to the constant strain of people walking on them.
Bonus cup design: A closed cylinder with a spout, facing away from the drinker's face, at the top. Pushing a button opens the spout, and you pour the drink from the spout onto the roof of your mouth.
[Answer]
>
> How would houses change if we could walk on the walls?
>
>
>
You would have to have carpets or lino everywhere. You can't leave foot marks all over emulsion paint.
Toddlers would be a pain. They could stick their fingers into light fittings mounted on the "ceiling".
Windows would be a hazard. If you tread on the glass and break it (or don't notice the window is open) do you fall out of the window or does gravity work differently on the inside and outside of the building?
Mains sockets will be worse than they are now because where do you put them? Several on every wall, floor and ceiling?
Don't open the velcroed-to-the-ceiling fridge without thinking or the contents will fall on you.
[](https://i.stack.imgur.com/arLjr.png)
Pets would have great fun running around the walls until they jumped. Then gravity would suddenly come from an apparently different direction and splat them on the floor.
Designing a squash court would be a challenge. What happens if you or the ball cross a gravity boundary in the middle of the room?
Vacuum cleaning?
Very tall and wide rooms to avoid heads clashing in the middle?
Heads *would* clash on surfaces at right-angles to each other.
[](https://i.stack.imgur.com/VBVwC.png)
Which way up would the TV be so everyone could watch?
[Answer]
It depends on the constraints. If you have loads of space to build then with a large sprawling house with plenty of floor-space, walking on the walls doesn't add a huge amount of valuable space; in fact you lose space because you need to leave space around the outside of the room to access the wall.
If, however, you have limited building land, then houses could be built vertically with a very small footprint; say you want a house with 4 16ft x 24ft rooms, with a ceiling height of 9ft, you could build that on a 16ft x 9ft parcel of land, whereas in our mundane world you would need at least 32 x 48.
] |
[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/136795/edit).
Closed 4 years ago.
[Improve this question](/posts/136795/edit)
A time traveler goes back in time (one-way trip, and he does not get to choose the exact destination) to a low-tech society, similar to medieval Europe. His objective is to kickstart an industrial revolution as quickly as possible, and the king of the place he lands in, takes him seriously, wants this to happen and lends active assistance.
He *cannot* bring any modern equipment back with him, only the knowledge in his head.
He *can* have any obscure but available knowledge that will help. The exact formula for gunpowder, or the procedure for purifying useful quantities of penicillin? Sure, he can fortunately happen to remember those.
He *cannot* gain advantage from knowledge of historical events. The reason in this story is that he has gone sideways as well as backward in time, so has landed in a place that resembles medieval Europe, but is not our Europe. But if you prefer, take it as a meta-condition: the question is about the use of knowledge of science and technology, rather than knowledge of historical events, so suppose the time traveler simply happens not to know of any imminent invasions, assassinations or such like.
The king is a practical man. Revelations about the stars being other suns or the nature of atoms are well and good, but what he's actually interested in are ways to improve the security and prosperity of his kingdom. (In other words, the topic is applied knowledge. Pure knowledge for its own sake would be a different discussion.) Sooner is better than later.
I can see how there is enormous advantage to be gained from later developments like rifles, steam engines and mass production. But I'm having difficulty seeing how to gain much practical advantage quickly. It seems likely to take a long time to go from gunpowder to militarily useful firearms, for example.
What is the first innovation that could be developed with future knowledge and local tools and resources, that would provide significant practical advantage?
[Answer]
My money is on Germ Theory. This is a good candidate for a few reasons.
1) Everyone in the modern world has at least some idea about it. Your time-traveler does not need an advanced education to get the idea across and implement it. Keep surgical equipment clean, quarantine sick people, doctors need to wash up between seeing patients, and you're done.
2) It requires no pre-existing technology or equipment. It works at any time period and on any sized society, from a stone-age tribe to Colonial England.
3) It will dramatically increase populations. More people means higher GDP, which tends to mean faster technological growth.
[Answer]
# Accurate World Map
Being able to draw a highly accurate map of the world would be a huge boon to any seafaring or trading nation. Moreover, knowledge of other civilizations of the time period and their valuable trade goods could kick-start a trading empire.
This doesn't precisely answer the prompt, as it doesn't really improve technology much, but it gives the time traveler the resources to actually make their technological visions a reality.
[Answer]
I think there is a very simple answer to this question that avoids the question of broadness, but in so doing I'm inferring the *real* question to be 'What knowledge should a time traveller take back to jump start technology?'
The answer is the Maxwell Equations of 1861, and the knowledge that magnetism and electricity are in effect different manifestations of the same thing.
Ultimately, the Maxwell Equations were the *theoretical* integrations of these two fundamental forces, but from an engineering perspective you don't actually need these equations to figure out how to use the two together. School children do it by hand cranking a wire-wrapped axle in between two magnets, and this is ultimately why the knowledge of electromagnetism is so important; it means you can create energy by turning an axle, and turn an axle by applying electricity. This is a ubiquitous element of our modern technologies by virtue of the fact that we can essentially transmit energy in a portable and useable form to wherever it's needed. That versatility revolutionised all the advancements we gained even through the Industrial Revolution, and in a medieval society, would even give them access to plentiful energy WITHOUT using coal or oil to the extent they ended up doing.
Ironically, this would result in a reverse-steampunk scenario, where fantastical ideas would emerge from electrically driven devices out of mindsets that haven't industrialised yet.
What an industrial revolution WOULD add that isn't currently in place is the ability to scale this technology up. In the first instance, I can see plenty of homes having their own windmills, watermills, etc. to generate enough power for their personal needs. You would end up with literally a cottage industry of electrical generation techniques, all powering personally designed products at different amperages, wattages and the like. So, the reverse-steampunk effect would at least be visually intriguing because of the variety of tools that would all employ electricity in different ways to solve the same problems.
[Answer]
Im going to go in a different direction from most of the current answers, The king would like any methods to improve his kingdom and you want to start an industrial revolution. Don't start with the natural sciences start with the people and policies:
1. A production line drastically improves the rate of production of crafted goods
2. Tax policies - support industries and research
3. Foreign treaties - make it so that you can attract foreign talent
4. Make some level education compulsory for all people
5. Support collaboration over competition for research and have it available to all citizens
6. incentivise innovation
Now you have a baseline to start from, within a few years the revolution should kick off on its own rather than just being based on you and your ideas. Bringing in some useful formulas would be a helpful boost but there is a limit and once you hit that limit you will need to rely on others to keep the innovation going.
[Answer]
There isn't really any one invention you could drop in as *"the first innovation that could be developed with future knowledge and local tools and resources, that would provide significant practical advantage"* that wouldn't really be just a matter of opinion.
from comments.
>
> The printing press with movable type was invented sometime after 1400 so that would be a good one, raising literacy & availability of printed manuals led to a fairly big boost in technical advances.
>
>
> Crop rotation (four field crop rotation) is another simple idea that produced fairly significant increases in crop yields, that was invented sometime in the 1600's
>
>
> The concept of microbes & bacteria, boiling drinking water, sterilizing medical instruments etc is another recent one with significant far reaching effects for an early society.
>
>
>
Are all good in there way but (if I'm reading your question aright) you want something that's going to spark further innovation & technological advances in & of itself without much further intervention?
* The steam engine is an easy one with the help of a blacksmith & could have all sorts of implications from agricultural threshing machines to transport, it's the bedrock of our own industrial revolution & once you've any one type of steam engine in relatively common use innovation around this particular bit of tech will rocket.
* The microscope & telescope were invented in the 1500's & 1600's, a lot of science couldn't get started until we had those & it lets you point at those tiny little things in water & say "see this is what we're killing when we boil it so that you don't get cholera"
* The copper zinc battery
* The copper wire electric generator & motor
For those you just need glass-making, blacksmiths, carpenters, pottery & a few cattle (for the batteries, any idea how strong the acid in a cows stomach is?) which are all available in 1200.
Electricity seems like a really important one (alongside microscopes & telescopes) if you want to kick start science really early (which is why I threw in the battery & electric generator / motor), but for them to be anything other than curiosity or novelty items you need something to use them with & I'm at a bit of a loss as to what invention might make use of it that a medieval society would find an immediate & compelling use for so that it would be widely adopted.
Radio might be plausible as a use for electricity with [foxhole](https://en.wikipedia.org/wiki/Crystal_radio) crystal radios for reception & electricity needed for the transmitting sets, any medieval king would love something like that for his armies, I'm just not sure if the required materials could be sourced in a medieval society.
Watermills & windmills already existed, the Dutch certainly had windmills back then, not so sure about the English.
[Answer]
Health information: first aid, personal sanitation, community sanitation, germ theory. That gives you an immediate leg up when it comes to dealing with things like sickness, disease, and public health. A lot of it is simple behaviour and habit and doesn't require a ton of infrastructure.
After that, a lot depends on what level of tech you'd find was already present, but things like the Bessemer process for cheaply producing mass quantities of steel would be good almost any time and weren't technologically too advanced to be created. And once you have cheap steel in mass quantities, all of a sudden you're looking at a whole new world.
[Answer]
All other answers have the precondition that innovation stays inside the borders of the country.
If this is basically our Earth, then the single biggest question for medieval Europe is who gets to America first - and then who can keep it. Spain became the richest nation in Europe through their gold and silver mines in Mexico. Britain then displaced Spain through state-sponsored piracy and having better ships (and captains).
If your hypothetical country has a coast, then the lesson for medieval and Renaissance Europe is that the people with the best navy win. With better ships, and by essentially controlling the seas, you free up your explorers, traders and settlers/miners to make you money.
[Answer]
A horse-drawn [seed drill](https://en.wikipedia.org/wiki/Seed_drill) - this will allow your farmers to plant their crops much faster, much easier, and in a more regular pattern (to they do not choke each other as they grow) - of course, even a modern steel plough instead of an old-fashioned Wooden or Iron plough would make agriculture easier! (Stronger, sharper, and damp soil is less likely to stick to It and slow it down)
Over a longer term, combine this with modern crop rotation (e.g. the [Norfolk four-course system](https://en.wikipedia.org/wiki/Norfolk_four-course_system)), and you can ramp up food production even further
Add in chemical fertilizers, or a set of Harvesting machines, and you should find you produce more food with less farmers - allowing you to increase general prosperity. (Before attempting a Combine Harvester, create separate Reaping, Threshing and Winnowing machines. The first can be horse-drawn, the second two can be static units powered by a water wheel.)
Now that you have a surplus of both food *and* workers, you can start to tackle other areas of industry - remember, a Revolution requires Revolutionaries!
[Answer]
Already some really good answers in the comments, I'd just like to suggest an alternative approach:
**Communications**
While the concept of the [Heliograph](https://en.wikipedia.org/wiki/Heliograph) is simple, it wasn't invented and used in an organised, systemic way until roughly the 1820's. There may have been some isolated cases of using mirrors and shields to pass message, but evidence is spotty at best.
Your time traveller could help the King set up a series of lamp-and-mirror stations through his Kingdom, to rapidly pass messages along. This would increase response time to an invasion by a orders of magnitude, and allow information and intelligence to be more rapidly spread.
Communication would be via Morse Code, and he could also teach them a thing or two about modern cryptography and compression, to further increase their security and efficiency. Some of this could be applied to the King's normal messages as well.
Depending on our time travellers electrical knowledge, he could also attempt to build a bare-bones radio transmitter and receiver. Called a [Spark-Grap Transmitter](https://en.wikipedia.org/wiki/Spark-gap_transmitter), it basically emits a large pulse of electrical energy that could be detected with a simple crystal radio set up some kilometres away - more if you manage to refine the design. Electrical power could be provided by a simple generator, perhaps turned by a windmill, waterwheel, or handy peasant.
[Answer]
I see four points with varying costs and high benefits:
* Penicillin (as you noted), hygiene, simple medical advances
more population, more health, more workers
* transportation -> trains
simple but very effective, enables the transfer of knowledge, goods and troops, freeing a lot of resources and boosting research
* communication -> telegraph
knowledge transfer, faster reactions, etc.
* food production, simple farming machines, some theory of farming, generally a focus on providing more food and storing food
the industrial revolution was kickstarted by agricultural advances. If 90% of people produce food all day, that's really a problem.
Really all boils down to having more people with more time able to dedicate time to learning, research and inventions. The rest is history.
] |
[Question]
[
Some hundreds of years ago, all humanity was removed from the Americas. In fact, most humans are gone from the world altogether. In the intervening time, nature has overrun the formerly human dominated landscapes of the former United States.
The area referred to in the title is the lands formerly around New Orleans. Much of it is underwater after a millenium of global warming and sea level rise; but what remains is cypress and tupelo swamp, live oak thickets, and grassy fire-dominated pine savanna. It is hot and humid in the summer, wet all year round, and rarely freezes in the winter.
In short, this is the perfect environment for the [capybara](https://en.wikipedia.org/wiki/Capybara). 1000 years was enough time for many Central American animals to migrate up to the swamps and savanna of former Louisiana. Jaguars are here, along with peccaries and brocket deer. In addition, many escaped domestic animals--horses, cattle, [chickens](https://worldbuilding.stackexchange.com/questions/114132/humans-are-gone-do-the-chickens-make-it)--roam the savannah. But the problem with the capybara is that it is starting pretty far away in the Orinoco Delta of Venezuela.
There are two ways the capybara could get from Venezuela to New Orleans. It could walk along the Mexican coast; or it could island hop, spreading across the many capybara-friendly islands of the Caribbean. **Can capybaras spread to Louisiana from Venezuela and populate it in less than 1000 years?**
[Answer]
**They are already here.**
Capybara in Louisiana.
<https://www.facebook.com/stevie.cox.165/videos/10155908203265712/>
blurry screenshot from video
[](https://i.stack.imgur.com/dpAVo.jpg)
Capybaras in Florida.
[](https://i.stack.imgur.com/ov3VN.jpg)
<https://www.youtube.com/watch?v=7NXGXrlQ2ZM>
Capybara in California.
<https://www.nbclosangeles.com/news/weird/Paso-Robles-Capybara-127771708.html>
[](https://i.stack.imgur.com/KCPhO.jpg)
People suggest the these capybaras are escaped pets. Maybe. Or maybe they have come through the Bigfoot dimension and are less wary about getting captured on film.
[Answer]
To travel about 7000km (the land route), given that the average capybara moves about [700 metres a day](http://library.sandiegozoo.org/factsheets/capybara/capybara.htm), it would take a lone animal about 10,000 days to make the journey. 27 years walking, they tend to live about 7-10 years, so he's not going to make it.
We're not talking about a lone animal though, we're talking about population spread. This means they don't move 700m a day but rather a distance the diameter of a territory per generation.
[Remember though](http://library.sandiegozoo.org/factsheets/capybara/capybara.htm#behavior):
>
> Rather sedentary habits allow ranchers to manage capybara without fences
>
>
>
The trouble with moving capybara quickly is you need to move entire groups, *fewer than 4 adults together won't raise young*, there are no parthenogenesis shortcuts here. So while individuals could be storm-blown on a raft to a new location, or an anomalous individual may walk considerably further than average, you'll need to build up reasonable numbers together to begin breeding.
Groups can be 100-500 metres apart. Breeding age at around 1yr. They're social, up to 100 in a group.
Assuming larger territories towards the edge of the range and smaller territories in the centre, and being optimistic, it could take 2 years for a small group to expand 1km. A very large population could move faster than that over a short period as the groups hit their upper size limits and force new adults out of the territory, but they might then not expand again for a couple of years.
Upper limit for the population to expand that far: Between 7000 and 70,000 years.
[Answer]
## This doesn't seem like enough time.
What is the driving force for the capybaras to move so fast to somewhere so remote? Animals tend to move into new environments when the current one is overloaded and can no longer sustain the population easily (<https://en.wikipedia.org/wiki/Carrying_capacity>). So capybaras will need to thrive in their current habitat, then move to a new nearby ecosystem to look for easier sources of food, reach the carrying capacity of that environment then move again. Over and over again until they reach North America.
Given that capybaras live for an average of **10 years** and have pregnancies that last for **5 months**, this seems like it is going to take a very long time. Turn over is not going to be very fast.
Last I checked Mexico is also a desert and global warming will only make it even more of one. So this is a natural **bottleneck** for the creatures that will prevent them from passing. You suggested **island hopping**, but the islands on the path to New Orleans are very sparse and many of them will be under water after sea levels rise like you suggest in your question with New Orleans being squarely beneath the sea.
So to me it seems like they would never make it to North America. By the time they do, they wont be capybaras anymore, but an entirely **different species**.
[Answer]
As other [answer](https://worldbuilding.stackexchange.com/a/114968/4981)s have noted, 1000 years probably isn't enough time for capybaras to spread from South America to the North American mainland, but they don't need to.
I'd start by suggesting you don't need capybaras unless you really want them. [Louisiana already has some pretty big swamp rats](https://www.theguardian.com/us-news/2017/oct/31/louisiana-swamp-rat-hunters-rodents-of-unusual-size), the [nutria or coypu](https://en.wikipedia.org/wiki/Coypu), which grow as big as 20 pounds. As that link lays out, they're already a full blown infestation, from an invasive non-native species.
If that doesn't appeal to you, there are already capybaras in the US, [and scientists are warning that they're poised to be the next invasive rodent species threat in north Florida](https://www.sciencenews.org/blog/wild-things/capybaras-may-be-poised-be-florida%E2%80%99s-next-invasive-rodent) (which is very close to Louisiana, of course)... the coypu/nutria having been the previous invasive rodent species in the American south. So, they don't need to migrate from Venezuela, the existing feral population in north Florida just needs to survive and thrive a bit.
[Answer]
There are two ways that capybaras could move a long distance in a thousand years. Both have been observed in nature.
First, they can walk. *If* the local conditions are right to support them, animal populations can spread very quickly. But, basically, for this to work, you need a continuous strip of dense forest with water covering the whole route. I don't believe that there is anything like that presently between Central America and New Orleans. If there is in your world, then it's perfectly possible for them to spread that far in a thousand years.
(Note that a concentration of predators along the route might act as a barrier.)
The second way they could get to New Orleans is to ride. Storms which produce major flooding regularly float very large rafts of trees and vegetation out to sea, and it's common for there to be animals trapped on the rafts. Most of them -- probably a very great majority -- break apart at sea and everything drowns, while others wander until everything dies of thirst or hunger, but occasionally such a raft gets pushed to an island or another continent and the hitchhikers are in a new home.
There are quite a few cases of island populations where where this is the only known way they could have gotten there, so it happens. What I don't know is the statistics of it and where this could plausibly be expected to happen in a thousand years.
[Answer]
Yes, it could.
Based on your description, I have a feeling that tornadoes and hurricanes will be more frequent.
They have the nice (well, depends on the points of view) habit of carrying things around, and it can surely happen that some capybara is carried along the storm. The few which will survive the flight and land close to an island can settle up there, until the next storm.
It's a sort of Monte Carlo based traveling, but I think over a time span of 1000 years it will allow a decent spreading of the capybara around, reaching even Louisiana.
see also [rain of animals](https://en.wikipedia.org/wiki/Rain_of_animals)
>
> Under this hypothesis, a tornadic waterspout transports animals to relatively high altitudes, carrying them over large distances.
>
>
>
[Answer]
Nutrias, which escaped from fur farms in Louisiana, [are already a major pest around the area.](http://www.businessinsider.com/nutria-rat-destroying-louisiana-2013-5?op=1) By 1950, there were 20 million of them in coastal Louisiana, before [major efforts by humans reduced the population](http://www.nutria.com/site2.php) (including paying a $4 bounty on nutria tails). They got to be so much of a problem that one former sheriff of Jefferson Parish sent out SWAT teams to shoot them.
The big herbivorous rodents with spiky fur living in the bayous are therefore probably going to be nutrias. Even if capybaras could make the trip (probably a breeding pair of escaped pets rather than a migration from South America), they would have to compete with the feral nutrias.
] |
[Question]
[
In my scenario, people behave after a certain "transformation" similar to Zombies. However they are not "undead", meaning that they cannot raise again after their body functions completely are out of order. Their behavior resembles those of zombies in the following way:
* Not capable of having verbal interaction with non-transformed humans
* Hostile towards every mammal which is directly encountered
* Regards human flesh as nutrition like flesh of any other mammal
**My question**
Is it possible that a transformation which leads to this behavior can be caused by substances that possibly exist nowadays, probably also in nature?
**One option I thought of:**
Long exposure to a certain poisonous gas in an abandoned mine.
The exposure to the gas damages sections in the human brain permanently, which causes humans to lose any common sense, behave like rabid animals and triggering them to regard every living being as possible nutrition.
[Answer]
I read [How to Design a Plague that Causes Insanity?](https://worldbuilding.stackexchange.com/questions/14295/how-to-design-a-plague-that-causes-insanity) and [Would a prion be the most likely cause of zombies?](https://worldbuilding.stackexchange.com/questions/33351/would-a-prion-be-the-most-likely-cause-of-zombies/), yet I think the question is different here, and very interesting. It's reality-check, so I went to the wikipedia.
**1. Not capable of having verbose interaction with not-transformed humans**
This seems to be quite straightforward: [Communication Disorder](https://en.wikipedia.org/wiki/Communication_disorder). My personal preference goes to larynx malfunction (e.g. esophageal voice) combined with hearing impairment (frequent ear infections).
**2. Hostile towards every mammal which is directly encountered**
This is quite easy: make them always hungry ([Hunger](https://en.wikipedia.org/wiki/Hunger_(motivational_state))). For some reason, glucagon -
epinephrine - ghrelin levels are always high within their system. They feel always hungry, even when they're bloated full. Maybe their insulin and cholecystokinin (CCK) levels are always too low to stimulate the feeling of satisfaction as well.
**3. Regards human flesh as nutrition like flesh of any other mammal**
Thats' a bit tricky. In general, humans consider other mammals as source of food, although in general we prefer vegetarian prey (e.g. stag) to meat-eating predator (e.g. lion) steaks. Expanding that to include humans is unusual, but it has been done. It's called [Cannibalism](https://en.wikipedia.org/wiki/Cannibalism), and it has been known to occur in situations of extreme HUNGER (see #2). No biological reason has been proved to create craving for a particular food (over others, see [Food Craving](https://en.wikipedia.org/wiki/Food_craving)). It's usually attributed to psychological reasons. So I would say, that if somehow they could be out of the state of continuous hunger, they'd stop hunting humans.
Further research should propose specific viruses or parasites that could create such conditions as in #1 and #2 simultaneously. But! First, I'm not an expert in that field (or the specific stackexchange), and second, I'm not sure this is the answer vector you're looking for.
[Answer]
You're looking for some sort of (micro-)parasite.
Parasites are nature's [masters](https://en.wikipedia.org/wiki/Behavior-altering_parasite_or_parasitoid) of [reprogramming](http://www.bbc.com/earth/story/20150316-ten-parasites-that-control-minds) other animals to behave in odd ways. Expecially [toxoplasma gondii](https://en.wikipedia.org/wiki/Toxoplasma_gondii) is known to infect humans and it's possible that it affects us similarly to mice, which get attracted to feline urine, so that the cats can eat the mice and thereby get infected with the parasite. (It's likely that humans with the parasite also are more attracted to cats).
In your case you'll need to come up with parasite that somehow benefits from the infected humans eating other mammals (I've currently no idea for that). The answers to [this question](https://worldbuilding.stackexchange.com/questions/14295/how-to-design-a-plague-that-causes-insanity?rq=1), seem to go in the same direction so maybe also have a look there
[Answer]
[Bath Salts](https://en.wikipedia.org/wiki/Bath_salts_(drug)) is a broad classification for a type of drug that has been linked to *zombie* like behavior in humans. It is a psychoactive drug that often triggers extremely violent and anti-social behavior.
There was a famous zombie like attack that took place in Florida a few years ago.
[Face-Eating Cannibal Attack](http://abcnews.go.com/Blotter/face-eating-cannibal-attack-latest-bath-salts-incident/story?id=16470389)
Bath salts are an alternative drug for Heroin users.
Those would be the closest "substance" that you could use as a reference.
You could use the idea that scientists engineered a virus that produces this compound or a stronger variant of it.
[Answer]
To start with…
Real life substance you require would have to precisely damage human brain, which would be pretty hard to perform. This way you wouldn't have to administer 'substance' again and there would be no cure for state of 'zombification'.
Traditionally Zombies were created with tetradoxin, which precisely administered by shamans allowed to keep targeted people virtually dead till brain damage would occur. Resulting damage was often disabling ability to communicate and think, however really rarely resulted with zombie's indiscriminate hostility against every living creature or cannibalism.
For more modern approach it would be some narcotic or drug with strong withdrawal symptoms and degrading effect on human brain (may be, for example, old military stimulants or neurotoxin). Some natural substances (mostly marked as narcotics) may easily trigger expected hostility, however effect is usually unpredictable, temporary and chance for cannibalism is rare to occur.
For given scenario of abandoned mine it could be used for military to store some secret, non-public weaponry.
Precise combination of debilitating chemicals and enraging ones could over time degrade human, however it would be hard to encounter in normal environment.
For exposure on gases it could be mist with kind of modified rabies virus (technically more substance than living beings). It could result with expected hostility and lose on communication skills (brain damage and instilled by virus desire to infect other creatures). Still it would be rare for one to devour human flesh (maybe expect for specific local culture). Additionally it would result with rather short life expectancy for zombies.
[Answer]
It's not a question of what will do it but a question of how it does it.
What can be anything from a disease, parasite, drug, fungus, mad doctor, nanobots, voodoo witchdoctor.
Firstly it needs to restrict the higher brain functions (Cerebrum) effectually reducing the person to an animal level. There is no logic, reason or compassion, just survival.
Next it needs to affect the Hypothalamus which controls hunger and thirst so effectually you end up with a starving animal no matter how much it eats.
It could also affect the amygdala to increase aggression and perhaps stimulate the adrenal gland for increased speed and strength
Finally what would be cool is if the infected could recognize other infected (via smell most likely) and the brain releases oxytocin creating a pack mentality.
What you end up with is super fast and strong zombies that hunt in packs
If you want slow shamblers, you'd decrease adrenal activity, increase hunger more and reduce overall brain function
[Answer]
Okay, I am not here to argue with anyone, but I am a recovered heroin addict... I know bath salts are NOT used as an alternative to it. For a number of reasons:
1. The effect will do nothing to aide a heroin addicts "hunger" for the drug.
2. Methadone is easily accessible to anyone in those circles so bath salts just would not cut it. There are other reasons but this is not the forum for it.
But, on another note about the bath salts, I personally have seen a guy dive through a double glazed window onto the road below and when he hit the ground he proceeded to repeatedly headbutt the concrete floor, splitting his face open, smashing his nose, but felt No pain. So, for a short time, I guess you could say, he was in a similar state to what a zombie would be it.
As in pure rage, directed at anything that got in his way.
That's my "2 cents" for what it's worth.
[Answer]
I'm surprised no one has said [Rabies](https://en.wikipedia.org/wiki/Rabies) yet.
Pros
* 1-3 month incubation time (time from infection to turn)
* Agitation + Anxiety + Confusion + Paranoia + Hallucinations + Insomnia (= aggressive + tired)
* Fear of water (hydrophobia) because of the difficulty in swallowing (won't swim)
Cons
* Not very infectious (mutate to transmit via bite)
* Death soon after turning (3-10 days, mutate this to be less lethal)
Rabies is probably the closest thing to a zombie virus that currently exists. There was even a documentary (forgot show name) about how Rabies could cause the zombie apocalypse if it just mutated to be transmittable via bite.
[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.
Yes K2 has that effect.
<http://nypost.com/2016/07/12/multiple-people-hospitalized-after-k2-overdoses/>
Also bath salts has that effect.
<http://abcnews.go.com/Blotter/face-eating-cannibal-attack-latest-bath-salts-incident/story?id=16470389>
[Answer]
**Hypnosis**
It's common for a hypnotist show to make voluntaries behave like a dog or chicken and to try to eat raw potatoes. If it's a really good hipnotist he making a volunteer behave like a zombie is possible.
But how to extend it to apply as a "mass hypnosis"?
Hysteria can play a role, but maybe you also need some sort of drugs effect, maybe poisoning the air or water to make people more susceptible.
Note that you don't need to affect 100% people to make a huge mess, even if you can only affect a small initial contingent, clever use of the media can spread the hysteria like a wildfire.
] |
[Question]
[
This question is based off of an episode of the original Star Trek series that got me thinking.
Imagine the very near future were just starting to colonize mars and had placed 500 people from all nations on the planet, which was growing most of it's own food with occasional influx of new seeds and resources on rare visits from earth. Suddenly something goes wrong with their systems, they lose electronic systems knocking out both radio and most of the resources they use to grow food. With just the systems they have left they can barely produce any food, no where near enough to provide for the colonists, and they have very little stockpile of food to last them.
Earth will likely send a rescue mission as soon as they realize contact has been lost with the colony. However, larger missions will take some time to reach Mars, and they may not bring sufficient supplies to help the colonists when the arrive; not knowing why contact was lost they don't know what relief efforts are required. There is no way to feed the 500 colonists until rescue arrives.
The governor makes a difficult decision. He arranges for 400 colonists to be randomly selected and killed immediately, calculating that his colony can only manage to keep 100 alive long enough for an Earth rescue mission to arrive. When the rescue mission arrives it finds 100 men and women starving and close to death. The rescue mission brought only a small amount of food, not knowing what was needed and all mass slowing down the rescue as well as increasing it's expense. They feed the colonists that they can and are able to partially fix the food growth systems before evacuates as many as they can back to earth. In the end another 50 of the starving individuals die before the remaining few are able to produce enough food to sustain themselves.
The governor, who ordered the deaths of 80% of his colony, is also taken back to face charges for the organized murder of his colony. However, it is clear from how desperate the colony situation was when rescuers arrived that everyone would have starved if they tried to keep all 500 citizens alive, in fact if he had ordered the deaths of even more citizens odds are some of the 50 who died of starvation after the rescue mission could have survived as well.
How will the governments of the world respond to the systematic murder to save the remaining citizens? Will the governor be imprisoned or executed for his actions, or would they see it as a horrible but necessary response to the situation?
this is *not* a question on rather the actions are right or wrong, but how the governments will respond, these are not always the same thing. Moral questions aside how would our own governments respond, or bicker, in this situation? For the sake of argument lets say the governor was an citizen of the United States, but citizens of all major governments were on the colony and killed.
[Answer]
Just some points to consider:
**No one on Earth is King of Mars** Any sort of legal proceedings concerning actions performed on a foreign planet are going to get weird. You already mentioned that the colonists were from many different countries; everyone is going to try to take control of the situation, and I think it would mainly end in a deadlock. In the end, the governor might be the only authority on the crime, and thus is the only person who can prosecute himself. However, the testimonies of the other colonists also carry weight, so if they agree that the governor did the right thing then he/she should be fine.
**Hindsight is not your friend** With a few billion more pairs of eyes and a lot more time to look over the options, there's bound to be a better plan out there that the governor didn't choose. Humans make mistakes, but when lives are ended by those mistakes people tend to get angry.
**Human lives are equal, but not equivalent** You may argue that choosing who lives and who dies by random is the best option: in reality it's just the best way to wash your hands of the situation. Shareholders in the colonization effort may find that the colonists they were counting on got killed, while the colonists working for the competition survived; these shareholders may pull out of all further projects. Countries will do this too if their colonists fared worse than those of other countries. While people are going to be angry either way, the governor *could have* chosen more carefully and made friends in high places; the fact that he didn't may be good for public opinion, but bad for business. On the other hand, if his random process killed mostly women, children, and/or racial minorities, things could get complicated.
[Answer]
Here is a case that might be pertinent: [The Willam Brown case](https://en.wikipedia.org/wiki/William_Brown_%28ship%29). In this case, a ship hit an iceberg and 9 crewmen and 31 passengers were 'saved' on a longboat. However, it appeared that it was overloaded and might sink, so they forced 12 people to their deaths in the water (in particular NONE OF THE CREW were tossed in the water). The highest ranking officer in the boat, Harris, instigated tossing people into the water. He was eventually charged (in Philadelphia) with murder, but the grand jury refused to indict, so it was reduced to manslaughter. He got 6 months and a $20 fine. This is a direct analog of the Mars case you discuss. I'd say there PROBABLY would be enough sympathy to get the charges reduced, but there would be some punishment almost on principle.
[Answer]
I think one point that would have a huge impact on public opinion would be whether the governor had included *everyone* in the group from which to randomly determine who would be killed.
If he exempted himself and any others, then expect the full force of the legal systems to fall on him.
Likewise, if the method of "randomly" determining the group was not transparent, then a similar result would occur even if he was included in the choosing.
Now even if he is tried and found guilty, if he can generate a significant amount of public sympathy, perhaps convincing the public that he was truly devastated by what the situation required of him, then the punishment may end up being more symbolic rather than actual.
[Answer]
**If he is Russian, he will be a hero. If he's American, it's more complicated.** His fate will decided by the culture to which he returns.
Russian have a very strong bias towards doing whatever it takes to make the state survive and the glory of the state. Any society that places emphasis on the collective will likely hail him as a returning hero who saved as many as he could.
More individualistic cultures will have a much different view of his actions and will likely try him for murder.
Fundamentally this is an ethics question: Is it okay for one person to decide to kill many people in the hopes of saving a few instead of just letting them die. Humans have demonstrated a preference for letting things (people/animals) die through inaction instead of direct euthanization.
[Answer]
There are several things here. 500 people is not a lot of people. For a plan like this to happen peacefully and %80 to be killed off, the majority have to willingly accept this situation, or be completely tricked into getting killed.
As a colony I would assume there will be families with children of different ages. So these children will also be on the chopping block.
It is not easy to kill friends and family. The remaining/surviving 100 have to both agree to the slaughter and likely help participate. Unless all 400 volunteer to commit suicide.
Of course the simplest way to handle both the death and the selection would be suicide pills. There are 400 death and 100 life. First would be offering those willing to sacrifice themselves to take a death pill. Then all the rest are mixed together and handed out like a gumball ball machine.
Now if this is a unilateral decision and the governor uses a small cadre of security officers to implement this plan, then he and any surviving executioners are going to be put on trial.
A point to note. 400 dead bodies are a LOT of protein. They would make a considerable difference in the food stores themselves. Making it possible to kill fewer people or at a slower attrition rate. Nasty? Yes. But we've seen it happen time and again when survival is striven for. If you get to the point you are willing to kill your fellow man to 'steal' their food, it isn't too much farther down the road to turn them into food.
[Answer]
This would be a very interesting jurisdictional scenario. If a particular country claims jurisdiction over the colony then the legal system of that country would have authority. It is also possible that an international panel would be constructed to handle this situation, but this would require international agreement (at least among certain countries) on specific legal definitions and, more challengingly, the punishments. Given the international disdain for the death penalty, it is extremely unlikely that it would ever be exercised in this case.
There are a couple of distinct ways this could play out that change the legal consequences:
1. The four hundred lottery losers take their own lives.
2. One or more executioners volunteer to kill the four hundred lottery losers.
3. One or more executioners only kill the four hundred lottery losers after being issued a direct order.
4. One or more executioners only kill the four hundred lottery losers after being threatened with physical harm.
5. The populace rejects the premise of the lottery and four hundred people are killed in the ensuing riot / chaos.
The legal violations and the people responsible will vary by scenario (and realistically, there could easily be a mixture of situations). If no homicides take place, there are few major charges that could successfully be brought on the governor. If executioners do kill, but both executioner and victim act willingly, the executioners could use justifiable homicide as a defense or dispute that it was even a homicide in the first place.
As the scenarios get worse from here, there is real legal culpability that must be dealt with. If a military chain of command is used to force executions, the legal situation will become much more complex and responsibility will land on the officers giving the orders. If the executioners will only act under threat, this will place some legal culpability on whomever is threatening them. If the entire situation turns into a bloody riot with people fighting for their lives, the governor (and others) are likely to face very serious charges.
In the last three scenarios, legal defenses are going to work very hard to classify the deaths as justifiable homicide. As the scenarios get increasingly worse, the legal concept (in U.S. law) of [necessity](https://en.wikipedia.org/wiki/Necessity) would most likely be the tool to argue justifiable homicide in the case. The success or failure of these defenses will be determined by even more specific detail than it’s worth speculating on here. Ultimately, however, the governor’s legal culpability is going to be unpredictable. Public opinion of this event and the governor’s actions will most likely influence how seriously he is pursued or charged on these crimes.
[Answer]
The trial is likely to go either way. There are just far too many variables at stake here. However, going by the existing case law, it is unlikely that the governor would be convicted of simple murder.
The act of [survival cannibalism](https://en.wikipedia.org/wiki/Cannibalism#Cannibalism_by_the_starving) is a well documented activity by people who are on the verge of death due to lack of resources. It was reported during early American history in the case of the [Donner Party](https://en.wikipedia.org/wiki/Donner_Party#Claims_of_cannibalism), as well as [during World War II](https://en.wikipedia.org/wiki/Cannibalism#World_War_II).
For inspiration, we can look to the famous nautical law case [*R v. Dudley and Stephens*](https://en.wikipedia.org/wiki/R_v_Dudley_and_Stephens). In this case, four men killed and cannibalised one of their fellow shipwreck survivors in order to survive with limited supplies during the shipwreck.
When they returned to England, the men were sentenced to death, but the sentence was later commuted to imprisonment. The [case law](https://en.wikipedia.org/wiki/R_v_Dudley_and_Stephens#Legal_background_and_theory) for killing others to survive generally consists of punishments other than those that would be imposed for murder.
Therefore, in the modern day era, to prevent serious diplomatic issues, it is likely that the governor would be punished, but it is unlikely that the governor would receive the death penalty.
[Answer]
I'll confine myself to the question as asked.
First, the political response will be one of outrage, particularly from those countries which had provided colonists among the unlucky 400. If the governor is American, the response will get particularly nasty. Wars have been fought for less (See [the War of Jenkin's Ear](https://en.wikipedia.org/wiki/War_of_Jenkins%27_Ear)), although that sort of thing seems to have gone out of style. The governor's survival will be a particularly sticky point, unless he can provide iron-clad proof that he took his chances along with everybody else. And since he had months to jigger the evidence, such proof is unlikely to be forthcoming, and there will always be a reasonable suspicion that he engineered an exception for himself. 500 choices is large enough that some statistical variations from the mean are quite likely.
If the distribution of deaths is in any way favorable to any nationality or race, things will get very bad very quickly. An uptick of terrorism against the favored group(s) can be expected. Also to be expected is the rising of all sorts of conspiracy theories among the victim groups. Riots are a given.
[Answer]
First question is jurisdiction. Is this an independent colony, under it's own sovereignty, or is it a colony of an Earth based nation? If the former, then it's really a question about international human rights conventions, if the latter then it depends on the nation.
Either way, the defence is basically *quod est necessarium est licitum*, that which is necessary is lawful, and for the premeditated killing of hundreds of people ... well, no amount of rationalisation, no matter how foolproof, is going to get you off completely. It's politics as much as justice. Let's face it, we in the developed world like our killing to happen in small, regular, impersonal batches.
There's a lot of other factors which will affect the outcome, but I doubt things look good for our poor governor. He better hope that he's tried in EU jurisdiction where there's no capital punishment, because he will be tried and it could easily go either way.
[Answer]
This is a very very nasty and ugly question to deal with. Therefore it will be swept under the rug.
On his return he will be escorted into a tiny room. He will be told what to write on his suicide note. Then he will be given the option of taking cyanide himself or being shot and having it staged as a suicide.
He will both be derided as a criminal and a hero but there will be no need for a trial. There will be a hearing but no one else will be held responsible as conveniently all blame can be placed on the man who is dead.
The world will build a memorial to the people that died and move on.
] |
[Question]
[
It's a few years from now, and someone **needs killing** at a remote secure facility, where a dangerous AI is being developed by a terror organization hiding behind a respectable corporate front, which prevents *my* organization from launching an outright missile strike against the facility. After much effort, I now have an agent inside the facility.
However, the villains are genre-savvy, so:
* Everyone at the facility has always-on implanted devices that constantly transmit video (from a diamond shaped sensor on one's forehead), a wide array of bio-signals, including heart-rate and other standard metrics, as well as real-time streams on the content of the gut and lungs, GPS with centimeter accuracy.
* There are 3D scanning sensors in every room and hallway that store volumetric voxel data at cubic micron resolutions for months.
* The food comes in the form of tamper-proof containerized MREs. The water/soda/juice comes from a secure, modular supply that is refreshed under security oversight. There is no alcohol on base, except in the medical facility, which my agent, as non-medical personnel, has no direct access to.
* There are armed guards sweeping the facility at a randomized intervals, with a maximum 5 minute interval between sweeps, with canines trained to detect explosives and common poisons. All labs and personnel residences have secure carded and biometrically protected doors, and are designed to be fully visible from the hallways across glass walls.
* A full weapon check of belongings and an intrusive body CAT-scan is done for all arrivals, as well as any incoming shipments. This includes a radiation scan.
* Electricity is limited to 5-Volt USB-C ports, except in the secured server rooms. There is no access to gas-stoves. No animals besides the K9 units are allowed on base.
There is a common dining hall, and all staff have individual sleeping quarters (all subject to monitoring, of course). Labs house 5-20 people, and the full staff is about 250. The agent has access to most labs, including the one of their target, but no direct access to sleeping quarters, security center, facility maintenance areas, server rooms or medical area.
**Yet, for the safety of the nation, one of the researchers must perish. I have one agent inside the facility. Yet it is imperative that the agent not be captured, lest brain-damaging truth serums used on them would extract a confession and the scandal could bring my organization down. How can he/she do it and avoid detection for at least 5 days, which is half the average interval between (the randomly timed) arrivals of transport shuttles (access is by military helicopter or boat) at the facility?**
More specifically, I'm still thinking *poison*. Is it possible to poison someone, and have it be slow-acting enough that my agent can get away? (I am however open to other avenues if poison does not work).
[Answer]
While a suicide attack is perhaps the most likely to be effective, I would question the idea there is only one "indispensable man" in the opposing organization. To work on and create a high level project is going to need a lot of resources, and many people who know portions of the project and who could (with suitable management and resources) pick up the project and carry on, perhaps more slowly than before but still capable to carry on.
So your assassin needs to eliminate *everyone* involved in the project. Luckily for you, the enemy have done most of the work themselves. All the important personnel are sealed inside what is essentially a giant vault with an amazing number of connections and interlocking systems. Your assassin simply needs to introduce malware or physically crash the security system to lock all the doors in the closed position and turn off the ventilation, lighting and outside communications lines. (Actually an SoF team outside can probably handle the destruction of the antenna farm and telecommunications hub leading into the building, but cutting off access from the inside is "cleaner").
So their "in" is to either come to work as an IT tech, or have the ability to memorize and write blocks of code and induce it into the system from wherever else they are working. They can even escape if the malware is triggered by a timestamp or other event inside the facility (timing it for the 6th daily login of the prime target would be good), so the assassin comes in, sets the malware trap, then leaves five days later. On the 6th day, the facility suddenly goes into lockdown (with people locked inside their rooms or workstations) and shuts off all communications, and the people trapped inside will asphyxiate, starve or die of dehydration. Turning off the lights will induce panic in a lot of the staff, and drastically hinder the ability of the people inside to take effective measures to rectify the situation. Since they will have to break down or otherwise cut through armoured doors to move around the facility, they will use up air and water at a furious rate and their time window for doing things will be quite short indeed.
If you can "spoof" routine comms from the facility for 72hr, then you have a very good chance that the majority of the people inside will be quite dead before SPECTRE is aware of the problem.
[Answer]
Target the point of vulnerability, rather than the point of strength. Unless this researcher never takes vacation, leave for family emergencies, or the like, he/she will eventually go home or to a mall or other public venue. You can then use whatever discreet method you choose to eliminate the threat.
For example, NCIS had [an episode](http://ncis.wikia.com/wiki/Yankee_White_%28episode%29) where the chosen method of silent execution was poison from a [Coastal Taipan](https://en.wikipedia.org/wiki/Coastal_taipan) applied to the victim's jacket.
So just wait at his/her house and plan/follow from there. If you want to be more sure, have your agent on the inside get to know the researcher and report when he/she leaves and whereto. Maybe have the agent leave with the researcher and call "a friend" to make dinner arrangements.
[Answer]
The following plan is based around one idea: you can't escape if the murder is discovered. That's rule one. There are no other rules.
They are obviously paranoid about security. If there is an unresolved murder in the base, fat chance getting on that transport. See rule one.
Their security system is, for all intents and purposes, undefeatable. 24/7 monitoring through implants mean you can't escape surveillance. Chances are the only way to get a decent window of opportunity would be to destroy the security. I'll refer to rule one on that, unless...
Unless you conceal why the system was destroyed. There's a French saying: the more obvious the lie, the more believable. There are very little things more obvious than full frontal assault. And if you make a good attempt at it, it will look like your only objective.
---
This requires three things: paid thugs or any militarish force, super-ultra-elite squad, and a big-ass EMP.
The EMP's role should be obvious: destroy security. Even if they can replace every component, they'll need to reinstall and reset all of it, which could take weeks. This should also disable any uninterruptible power supply system in place, which at this point is barely relevant.
The elite squad doesn't have to be big, but it has to be highly-trained, special forces, sneaky soldiers. The main troop can be anyone capable to hold a gun and shoot people without getting wiped in an instant. My recommendation would be mercenaries, bonus points if you can just eliminate them once it's done. That will cost you money though, but apparently you're trying to save the world so following budget should be pretty low on you priority list.
So what you do with that is you just plain attack the facility. Nothing subtle about it, not as far as you troops or their security is concerned. You should attack around wherever the target is. The reason is your elite squad will go there to grab a random assortment of equipment and intel, but also to capture random people. How much you should take? Enough that it won't look targeted but rather an opportunistic grab.
Your agent has only one task: neutralise the target (dead or alive) and bring the body to a designated location. Ideally, they only know that the attack will happen and that they have that one mission.
Before turning back, your elite squad grabs the body of the target. Once it is safely out, break off the attack. Make it look like you bit more than you could chew. Your elite team must survive and extract with all their loot.
---
As you can note, it might be a bit crazy and over the top. It's probably not perfect either. However, it introduces one idea: that instead of concealing your assassin, you conceal the assassination. With all the chaos an attack would cause, nobody is going to keep track of who is doing what. And if they do, add them to the body pile.
Your agent's role is minimal. Their knowledge is limited. They have one simple mission, they just know that when the lights go out it is time to strike. The less they know, the less suspicion it should throw. In the aftermath, once security is restored and they count their loses, they'll have lost random equipment and people. It could be impossible to determine whether there was an intended target or not. There would be no particular reason to suspect your agent. And if they can't suspect you, you don't even have to extract, you could remain inside, and leave much later or not at all.
I'll freely admit, this may not be applicable in your case depending on what your organisation has at their disposal. However, the general idea of concealing your true purpose rather than concealing your identity is, in my opinion, the best way to get away with it.
[Answer]
The simplest solution is to have a suicide assassin. Walks up to the target breaks his neck, and injects air into his own carotid artery, using his 'diabetic' syringe.
Of course Assassins are now highly trained individuals and aren't ramped up on hashish any more, and it costs a lot to train them. On top of that can you count on someone who's not brainwashed to off themselves at the end of the mission?
So to begin, why would you do the killing the day after transports leaves? 5 days in between transport, then you don't set thing in motion until close to departure time.
You should also have at least one agent working on the boat, to help the assassin escape when he needs it. Anyone would be helpful, but one of the officers would be much better.
This would allow for a submarine pick up by the ship agent signalling to a sub, and the assassin jumping overboard at some point. This is in case they discover the assassination before the ship docks.
Now for trying to get around the tech to do some killing. The big thing about all the surveillance, is that most of it is only good AFTER the fact, to see who did what and when. They will most likely be able to figure out who did the killing and maybe even how, but there is just too much being recorded and viewed to catch everything in real time. Guards get lazy when they don't have anything happen.
So befriending the guards and their dogs would be a reasonable first step. Start by finding a bench or something in their route to always take your break at. Wave and admire the dogs.
Now my suggestion would be [Thallium poisoning](https://en.wikipedia.org/wiki/Thallium_poisoning). Of course the hard part is, how to get the target to ingest it?
We might start with either smuggling it in, in a eppy pen for someone with severe allergic reactions. But another way might be to somehow bring in a favorite food or spice of the target, and 'share' it with them. They might be able to get personal food in, (since they will be the ones eating it) and spices or spice mixes are easy to share and with MRE style food, after a while new flavors will be a luxury.
Might start by bribing the guards you've befriended to let you bring this special treat in, (all clean and fine). And as they get used to your shipments, start sharing it out. As long as you have the antidote available you can even take some of the poison when 'eating with' the target. It apparently takes [about 40 to 450 mg/m^3](http://www.cdc.gov/niosh/idlh/thallium.html) which is the size of a large aspirin in volume to kill a 70kg person.
It is odorless and tasteless and dissolves quickly in water. Might even be able to have enough in a little drink mix packet for flavoring water...
The big problem is that once discovered, it is pretty easy to treat, if discovered early enough.
[Answer]
Anyone can be killed; it's just a matter of the exit requirements.
If the agent does not need to exit but can't be captured and/or interrogated then a murder/suicide would be the easiest way of accomplishing the goal.
You would need someone that is fanatical enough for your cause to give their life for it and still well enough in control of their senses to complete the mission. The back story is apparently good enough that they made it past the obvious background and other security checks to get a job in the same facility as the target. So, as long as they don't spill the beans then your organization is covered.
The next step is for your assassin to become friendly with the target. Friendly enough to get close to them in a private setting. The assassin shouldn't strike at the first opportunity but rather build a relationship over a couple weeks. The reason is that you want it to appear like some type of lover's quarrel and not a hit.
So they get to know each other and, after a few weeks, the assassin goes "crazy" and kills the target using a blunt instrument. They'll want to start a verbal fight, then use a blunt instrument (maybe a bust) that hits the target on the head and kills them. Immediately afterwards the assassin would pretend to be overcome with emotion at the "accidental" killing and off themselves. Whatever method is chosen would have to be both fast and highly effective.
The end.
---
Another alternative, and highly Sci Fi in nature, would be to have the assassin's body changed in such a way that they excrete a highly targeted toxin (maybe through sweat?) which would only affect the target based on their DNA. Such a thing would likely be undetectable, wouldn't require more than the assassin to simply touch the target, and would allow ex-filtration at a convenient time. It could even be written that it's a slow working toxin that whose effects are irreversible after a certain number of hours.
[Answer]
Accidents happen. As long as the agent has no discernable motive and is good at acting, people might believe that he really is deeply sorry for
* dropping that big cargo box from the crane while it was above the target's head
* crushing the target's rips and puncturing their lungs while attempting to do the Heimlich maneuver
* stumbling into the target while holding a knife.
[Answer]
**Use a fire drill.**
Well, you can't kill someone with one, but it's your first step. Fire safety regulations must be followed by law by anyone trying to look like a legitimate organization.
You should start by hacking into the building's alarm systems and setting them off. All employees will be required by law to exit the premises until the fire department shows up. If you can actually overload something and start a fire somewhere: even better.
Once your target is outside, take your pick of ways of killing them. An easy way would be to just shoot them, and then have the police, who can show up with the fire department, arrest them before they can be compromised. This will probably be done by a person already outside the facility who knows nothing but the identity of the person they're supposed to eliminate, so as to keep your mole hidden.
Alternately, stage a terrorist attack on the facility, and then bring in the police/military to evacuate the building and locate the terrorists/bombs. Local law enforcement will absolutely not let anyone stay hidden in the building during a possible terror attack. Once your target is in the open, the real killer can strike (and then be arrested on the spot).
[Answer]
**Server room freak accident.**
This one needs a few steps in order to work :
The first part is the setup :
- Hack your own camera feedback so that you can loop it. (make it without looking at the automated hacking tool that you are using, probably a usb dongle that link to the closest wireless camera)
- Work for a bit, so you have something to loop onto.
The second part is the murder itself !
- Loop it !
- Give your target a reason to go to the main server room.
- Hack the server room security
- Lock the room door and start the fire suppression protocol. The one with air deprivation. As your enemy is paranoid, those doors should be quite resistant, so they would need to run to the other side of the building to get the set of physical keys. By this time your target will either be dead or severly brain-damaged.
- Stop the loop.
[Answer]
The best answer I can come up with to meet your requirements is **polonium-210.**
Made famous by the case of [Alexander Litvinenko](https://en.wikipedia.org/wiki/Poisoning_of_Alexander_Litvinenko).
I know this violates your radiation scan security measure but the way your security is written there are no obvious flaws so odds are your agent will have to find some way to fool at least one of the measures...particularly if you want to stick with poison.
The poison is relatively slow acting, I believe it took Litvinenko 22 days to die.
If your agent is able to bypass/fool the radiation scan it will also create a blind area for investigators trying to figure out what happened as they may be inclined to assume it was not something they check for.
From the description in the article the symptoms he experienced the first few days could be confused with a really really bad stomach flu. According to the article he was home sick for **several days** and you could plausibly make it shorter or longer based on dosage.
This should provide ample time for your agent to escape the premises before he is found out.
[Answer]
Keeping strictly within the restrictions which you have described, I would like to point out the obvious:
>
> ***Your agent is not getting out of there.***
>
>
>
At least not right away, but most likely not at all.
The main requirement, as I understand it, is that you maintain complete deniability of the assassination. This means that the agent must not be linked back to you, but not that he need survive, or not be found out.
There are two ways this could work:
**1) Laboratory Accident**
Depending on the equipment in the lab you might be able to stage an accident such as "accidentally" rewiring a console to a live wire. This is probably you best bet, although you will need to be able to perform these modifications without being caught.
Depending on the chemicals available a poisonous gas could also be released while the target is in the lab. Done right this might kill them before medical help can arrive.
**2) Binary / Targeted Poison**
This is more in the realm of science fiction, but also more likely to "work". I will assume you know a lot about the target, but simply do not have access to him. I hope that knowledge extends to a sample of their DNA.
At this point you can develop a poison which will target people with a certain DNA marker. Your agent should be immune to it, although many of the staff there will not. Let the virus loose into the facility and once the "epidemic" starts killing people left and right it will be very difficult to determine who was patient zero.
A variation on the theme can be a dual poison. Have your agent bring a seemingly innocuous liquid in. Maybe disguised as pills, which he can then simply dissolve into water to create the first stage of the poison. He can then add another seemingly innocent ingredient to the mix to create a very lethal poison which he can spill on the target's work station.
You are far more likely to be caught this way, but you've accomplished your mission.
[Answer]
Develop a lethal virus that has a short incubation period (days), a long period where symptoms are not visible but the carrier is contagious (weeks), and a short period where symptoms are visible before death (hopefully hours or days). One where the virus can be airborne is preferred, but even one where the virus can be spread by contact from the carrier, either directly (a handshake) or indirectly (carrier touches doorknobs which are later touched by other people).
Of course, you would need one that would not be detected by a CAT scan or other initial scanning techniques.
Infect the agent as a carrier and return him to the facility, with explicit instructions to remain at the facility and interact with the staff and victim frequently. Perhaps you might even want to inform the carrier of his infection and pending death, but perhaps not.
Wait. In a closed facility as described, the odds are good that everyone at the facility will be infected and die. Of course, you run the risk of breaking containment at the facility and starting the next Black Death, but many great atrocities are committed in the name of the public good.
[Answer]
Your guy could use a [memetic kill agent](http://www.scp-wiki.net/scp-001). He could print it on one of the pages of a notepad, then flip to that page as he walks past the target. It couldn't be detected by any security measures short of manually flipping through the notepad, and if anyone tried to watch the video of the murder to figure out what happened they would also die. The resulting chaos in the security department would probably buy plenty of time.
Bonus points if the meme is revealed in a crowded space and it takes the security team a few days to figure out that everyone *facing a particular direction* kicked the bucket.
[Answer]
Given the tech level of the requirements I think the proper vector is biological. You need an airborne vector pathogen with very high lethality. The closest thing that comes to mind is a strain of Ebola that's airborne but doesn't harm humans, only monkeys. Making something in a lab would be better anyway--you can make something that won't be so dangerous if it gets out. (Say, by being very sensitive to the environment.)
If it's a suicide mission he simply goes in during the incubation period. If it's not you vaccinate him and you encapsulate the bug in a shell of material that on x-ray looks like water. This capsule dissolves slowly, ideally you would use a few capsules that will dissolve at different times. These are introduced into his bladder. To defeat the CAT scan he makes sure his bladder is reasonably full at the time the scan is done--since they look like water (and what's inside is mostly water) they'll be invisible. The agent simply makes sure to cause lots of splash (I'm not talking about missing, splash will be enough while being much less obvious) when urinating. He must always stand to urinate. (Obviously, this approach requires a male agent.) As the capsules must be large enough to avoid being flushed out the insertion isn't going to be pleasant.
[Answer]
There are several avenues by which such a poisoning might occur, depending on just how advanced the site's security really is.
All involve poisons that are effective in small quantities that are easily slipped past the detectors described.
The first method is poisoning by [Ricin](https://en.wikipedia.org/wiki/Ricin). When airborne, this is lethal in quantities of less than 2 milligrams. When administered as an airborne compound, with a particle size sufficiently small, the scanning sensors would either not see it or consider it to be dust. The one potential drawback is that there is now an [immunisation against Ricin](http://web.archive.org/web/20110927092634/http://www.utsouthwestern.edu/utsw/cda/dept37389/files/271161.html), though it would be unlikely that the target would have received it.
The second method is poisoning by [Polonium-110](https://en.wikipedia.org/wiki/Polonium). Yes, it's radioactive, but it's primarily an alpha-emitter, and alpha particles are blocked by a fairly thin layer of solid material. The gammas it emits are a thousandth of its radiation output. Since Polonium is lethal in microgram amounts, it could be difficult to detect if suitably encapsulated to block alphas, and especially if those few micrograms are distributed around the assassin's gear. If the enemy organisation has radiation sensors, it should be possible to get a similar one and determine if the Polonium is detectable *before* risking the assassin.
Both poisons have the advantage of taking days before symptoms are noticed, and yet a longer time before they become serious enough to be taken for something less than merely inconvenient.
A very slightly modified [ecigarette](https://en.wikipedia.org/wiki/Electronic_cigarette) with its power circuit rigged to turn on automatically after a certain time could be used as a diffuser for the toxin, whatever it is. If the agent 'loses' it, despite the volumetric sensors, it could be some time before someone actually notices this piece of miscellanea amongst all the other miscellanea that humans generate naturally, from dust to paperclips to pens and pencils that have rolled under the furniture. Do the guards really notice and respond to every dropped pen, pencil, paperclip, coin, hair, flake of skin, crumb of food, or whatever? It's not stated that the 3D scanners can do anything other than tell the exterior shape of a thing, and while something like a gun would likely be recognised as a weapon, an e-cigarette likely would not.
Depending on the frequency of cleaning, a dropped item might remain out of sight for some time, probably for up to 8 hours (no-one wants cleaners disturbing the real employees when they're working), and potentially longer, up to days if the cleaners aren't punctilious about sweeping under and behind every bit of furniture. The slacker the cleaners have been observed to be, the longer the timer on the ecigarette can be set before it turns on, and the assassin may well be out of the complex before that happens.
The agent need not even know what it is that he is carrying. All he (or she) needs to know is that the ecigarette must be lost in the target's workspace after loading it with a particular substance. Not deliberately hidden, just plausibly accidentally dropped so that it lands out of sight. No matter how sensitive 3d sensors may be, if they can't see inside the assassin's pockets (and again it isn't stated that they can), there's no telling between a deliberate or accidental loss.
This accidental loss might require specific training in spycraft, but just about everything else the assassin needs to do would look entirely normal. If the poison is Polonium, then the Polonium could be extracted from its radiation-blocking carrier under the cover of blankets at night, in the dark. With training, the assassin could consider this a normal activity, and not be particularly nervous about it, though doing the task just after retiring after a pre-bedtime exercise session would throw off the bio-monitors, and the 3d sensors aren't stated to be able to see through things - if they could, they'd probably be emitting x-rays constantly, which could throw off radiation scanning in the admissions area.
If the agent was to be infected with the flu or a common cold just before infiltrating, the resultant outbreak of the inconvenient but hardly lethal illness could mask the much more serious poisoning.
[Answer]
As you seem to have access to considerable resources....
Before you send your agent in, secretly implant them (without their knowledge) with a dissolving capsule containing a bioweapon that spreads fast, has slow initial onset then rapid 100% fatality rate.
If you are feeling civic-minded you might want to leak to the press/UN/CDC that the facility is contaminated to prevent it getting loose.
Start nasty rumors about them ?
[Answer]
So you want your agent to kill the scientist, and escape unharmed. This is a tough one.
Does your agent have a "diamond shaped sensor on [his] forehead"? If he does *not*, then I think your best option is to **kill the power in the facility** for as long as you need to
1. **kill the scientist**
2. **grab the scientist's sensor**
3. **place it the agent's forehead.**
Then look away from the scene of the crime, and walk out when you can (as soon as possible, before the alarm is raised and people realize that the person wearing the dead man's sensor is an impostor).
There is a possibility of discovery via [heartbeat signature](http://news.discovery.com/tech/your-heartbeat-is-your-new-password-130903.htm), but your agent can explain to security that his raised heartbeat is due to the stress of the explosive attack (EMP?) on the facility. (*perhaps train him to raise his pulse in advance?*)
Good luck.
[Answer]
**Bring in a concealed toxin**
The first time that your agent enters the facility, they will not carry in any toxin. They will, however, bring in a keepsake that includes a secret compartment. The goal is to ensure that the secret compartment will be able to get past the initial security. In order to test this, the secret compartment should contain a small vial of high-proof alcohol - just enough to get only a little drunk (or some other mild contraband that will result in a slap-on-the-wrist level of punishment).
The keepsake can be claimed to be a gift from a family member with whom your agent is particularly close. Additionally, your agent should specifically ask about the secret compartment - "My <family member> keeps telling me there's a secret about this that I still haven't found. Did you see what (s)he is talking about, or is (s)he just pulling my leg?"
To increase the chance that the secret compartment will make it past security, the keepsake should be made of metal. The lining of the secret compartment should be lead, both to further prevent attempts to scan the object and to make the object feel as heavy as if it were solid.
The secret compartment should also be tricky to open (but not require looking at it to open). A fairly simple tricky way to open it would be sliding pins in a circle holding the compartment in, requiring the keepsake to be spun in order for the pins to all move out of the way at the same time. Another way would be for there to be a small bit of embedded iron that needs to be moved in a certain pattern (basically a hidden maze). Then a magnet would need to be moved along the outside of the keepsake along a very specific path.
After a couple time going through security without comment, you can be confident that your agent will be able to bring a toxin in inside the secret compartment. Given my lack of security clearance, I'm sure that there are a number of useful toxins that I do not know about. The ideal would be a slow-killing contact poison that can be absorbed via a handshake yet blocked by something like a particular lotion. Perhaps a biological agent with a sufficiently long incubation period. Your agent would be in the habit of regularly using lotion. Then when your agent is ready to act they would, as usual, sleep with the keepsake. After waking up your agent would open the secret compartment under the blanket (to avoid the scanners), apply the contact poison, and then replace the secret compartment.
All that would be left is to make sure that the target is one of the people with whom your agent will shake hands with that day. Then, after washing their hands, your agent will no longer have any trace of the toxin on them, and can safely wait until the next transport shuttle to leave.
[Answer]
A cup of water used to fake a choking accidental death. The sensors can not record behind them. Agent gets person to drink water, goes behind them faces away from them, and jabs, pokes, kicks, or etc to get victim to choke. May have to add a bit of water to finish job. Maybe blow some dust in their face to make breathing even harder.
My agent, "he just started choking, and was dead before I could react."
[Answer]
The murder is easier than one would expect - it's the hiding out for X days that will pose a much bigger potential for trouble.
# So, for the murder
*Death by acute radiation poisoning via polonium-210.*
Polonium only emits alpha particles - and the amount you need is so tiny that you can hide it literally anywhere - which makes it extremely hard to detect, as long as you are able to contain it in something that blocks alpha particles (which is virtually everything). A polonium-laced match carried in a matchbox, for instance, would not set off even the most sensitive radiation detector unless the matchbox is opened.
If inspections are this thorough, you may opt to sow a carrier into the fabric of some article of clothing or hide it in a fake tooth or what-have-you.
The time from "infection" to illness is, as with all radiation poisoning, generous enough for your agent to escape in the more immediate sense. You should expect illness to not occur until after a few hours at the earliest but also not more than a day later.
Administration can be whatever you like. It doesn't matter - as long as the substance ends up *inside* the victim's body. External application will most likely not be lethal.
# Avoiding detection?
This will be the hard part.
Unless your agent can reasonably administer the polonium without coming in documentable contact with the victim, you need to expect that your agent will be on the list of suspects. If your agent can somehow, without putting it on video or adding a trail of keycard-logs, for example lace the target's toothbrush with the substance, you *might* be in the clear. If successful, this method will be better for avoiding detection - but it carries the downside that if someone spots the agent or evidence is left behind, it will be much more damaging.
Furthermore, the polonium container/application apparatus needs to be disposed of somehow, as polonium can be tested for. You need to be able to incinerate the container and/or applicator, or throw it away in a suitably tiny & common recepticle so that its existence - if discovered - cannot be linked to the agent.
Example - let us assume that cigarettes are allowed and your target is a smoker:
* Identify which brand the target uses
* Acquire one (or two, for backup) such cigarettes and lace them with polonium
* At some suitable time, remove one (or two) cigarettes from the target's smoke pack and replace them with the poisonous ones - how to accomplish this while having a GoPro mounted to the agent's forehead 24/7 is left as an exercise to the reader
* Wait for the target to inevitably finish his pack and succumb to acute radiation poisoning
* Profit (in a best-case scenario, the agent might have already left the facility before the target dies)
[Answer]
Assuming the base has no network access outside of the facility, your agent could set up a switch that "accidentally" allows the AI access to the base systems on a wireless remote or a short timer. Then, simply wait for the next transport which will leave your agent's target(s) on the base, trigger the remote or the timer and sail off as the AI invades the base's systems and takes them over with perfect dramatic timing, then kills all the base's occupants. The evil organization probably will be in the dark about what happened until they can manage to retake the base and find the switch, and even if they determine who sabotaged them they can hardly come out and say that the sabotage was caused by releasing the AI they were creating.
This does assume the AI is evil because it wants to kill all humans it can, rather than evil because it will trigger a fire-sale in the stock market or something.
[Answer]
How about Thallium? It absorbs through the skin so put it in their toothpaste, mouthwash, shaving cream, lotion, spray on their clothing, bed linens whatever is handy. It is rather slow acting so your murderer could be out of facility at the time of death.
<https://en.wikipedia.org/wiki/Thallium_poisoning>
>
> Thallium was the poison of choice for Saddam Hussein to use on dissidents, which even allowed for them to emigrate before dying
>
>
>
So that ought to give the murderer time to get out of the facility even with a 5 day window.
[Answer]
First, using your agency to hire an agent for the job and letting them know who you are is crazy dumb. Tell them they work for Fake INC and feed them enough fake data for a plausible story if they were questioned. Next, you only tell them the minimum possible, go here kill this guy done. Anything they confess would be useless garbage or they would already know it.
Next you build an identical building so you can test things in safety in a closed identical environment.
It needs to look like:
1. Natural causes
2. Accidental death
You could also have many other non-related diversions.
If you could gain control over the speaker system remotely you might be able to time random ultra-sonic sound bursts(hopefully non-audible) to drive the target insane. When he/she goes crazy security will shoot them for you, no fuss or muss.
The problem with poison is it would have to basically be totally inert until the timed trigger. That specific of a poison is going to be hard to come by and if it is genetically engineered there are going to be a short list of possible labs it came from like yours.
If you could romance, a security guard that would surely be useful for tricking him into helping. Placing a hidden transceiver in their clothing allowing you to secretly attach to the private network and plant sleeper viruses all over. Guards will insert USB sticks get infected, and move the virus quietly around. Eventually random outages would start happening. Once chaos, or people start expecting the unexpected to happen, you rig an accidental death for a camera outage and get away with it.
A camera system of that complexity would have so many parts it would make it easier to break. The read/write requirements would be so astronomically high for 300 people plus rooms that any disruption would cause data loss. The computational requirements so great that all the computers would have to run flat out just to keep up. Security software wouldn't be that effective as they couldn't afford to dedicate a significant amount of resources to it. Therefore, a computer virus is likely to succeed. The vast amounts of data moving around would certainly hide a viruses transmissions. As is it piggy backs other packets and uses buffer overflows,underruns, and etc to break into active memory and then it would run silently in the background.
The amount of pointless data would likely allow gaps in the detection network that could be exploited.
IF you could get the cooling system to malfunction via virus or etc the system would quickly overheat and shutdown. Allowing a perfect opportunity for an accident. Especially if you can get it to fail many times, and people think nothing of it. The fact the person died will be a coincidence after the 10th power outage.
It would be even better if you can get his/her sensors to short out/malfunction causing them to kill your target.
[Answer]
What about custom made virus?
We could create highly contagious virus, which several days after infection is lethal. Our agent will be carrier, and his task will be to get into facility, and infect target.After that, we provide extraction for him and we remove virus.
Few days after, virus will kill our target, which might looks like natural death.
[Answer]
Thallium in fingernails? The agent cuts their fingernails, exposing the cross section spiked with Thallium, then somehow exposes the target to it.
[Answer]
amanitin, symptoms are delayed for several hours, and symptoms look like the flu, so rarely get treated.
ricin, takes days to kill and there is no cure. if injected the dose is so miniscule that if injected correctly you might never feel it. And putting the camera on the forehead creates a large blindespot. and dogs will miss any odorless toxin.
but really in a research lab a research lab accident would be your best bet, there are plenty of ways to kill someone in a lab accident especially if collateral damage is not a issue. many Organocadmium compounds are gaseous and medical help won't matter. Not to mention using a less destructive lab accident as a distraction, your security teams are not going to be patrolling while the lab is on fire.
there are plenty of toxins in which your medical teams is going to say, " well you were poisoned some time in the last 12-18 hours and there is nothing we can do to save you. And for many the dose is so small no scan or check is going to find it. no scan is going to be able to tell the difference between a couple grains of sand in your aglets or a couple of grains of ricin.
then you can go the other way with toxins that kill so quick
and lastly your facility will have some contraband, by banning it instead of providing it the company basically guarantees it. somebody will be making or sneaking in alcohol, because that's the way humans are.
[Answer]
**Let them do it themselves.**
Agent is terminal on some preexisting condition like blood cancer (of course she's healthy, but your organization will make her believe); Indoctrinated; Goes in, waits till subject holds a deadly sharp/thin object in her hands; Closes in on some pretext, touching subject on the wrist; Takes hold, cries 'What are you doing...?' and jams the sharp object into her own eye/jugular. Agent dies on the spot. Scientist will lament 'she did it to herself', causing the Organisation to administer the mind destroying truth serum to get at the truth. Mission accomplished (going from the precept that a destroyed-mind scientist is as good as dead).
This circumvents the problem of non-successful physical kills - even if the agent does not succeed, the obvious *attempted* murder will trigger a reaction as if it had, while if the agent tried to kill the scientist, and fails, failure to kill herself blows the plan.
] |
[Question]
[
Death occurs in extremely high humidity and an average temperature of 23 C (~75 F), both of which continue for six weeks.
At that time, temperature begins to fall over the course of eight weeks to an average of 5 C (~40 F). At the beginning of these weeks humidity decreases sharply, though the air is still quite humid.
The next three months are cold, averaging 0 C (32 F) and with moderate levels of humidity.
This is followed by eight weeks of warming and then a hot, humid summer of two months with temperatures as high as 40 C (~105 F).
A dry season follows for six weeks and then the cycle repeats.
All this time the body is clothed (clothing composed primarily of cotton), open to the environment and can be accessed by insects and scavengers.
In this weather cycle, about how long would it take for the body to be skeletonized?
Also, how long would it take for the bones to separate from each other and fall from the tree assuming it starts securely wedged between two branches?
I don't need exact amounts, just ballpark figures would be useful.
[Answer]
Probably not too long. There are a number of variables and it is necessary to know the precise trajectory of those conditions to exactly determine the actual [decomposition](https://en.wikipedia.org/wiki/Decomposition).
>
> The speed at which decomposition occurs varies greatly. Factors such as temperature, humidity, and the season of death all determine how fast a fresh body will skeletonize or mummify. A basic guide for the effect of environment on decomposition is given as Casper's Law (or Ratio): if all other factors are equal, then, when there is free access of air a body decomposes twice as fast than if immersed in water and eight times faster than if buried in earth. Ultimately, the rate of bacterial decomposition acting on the tissue will depend upon the temperature of the surroundings. Colder temperatures decrease the rate of decomposition while warmer temperatures increase it. A dry body will not decompose efficiently. Moisture helps the growth of microorganisms that decompose the organic matter, but too much moisture could lead to anaerobic conditions slowing down the decomposition process.
>
>
>
At a guesstimate the body will have completed its major decomposition during the initial six weeks of high temperature and humidity. The time for it to be reduced to a skeleton may take longer. A hot humid summer will go a long way to finishing this part of the process.
While the question mentions weather conditions, the role of scavengers and insects will also play a major role, these factors are lightly touched on in the question.
The probable sequence of decomposition would major decomposition during the first six weeks. During the cooling period, decomposition will continue for the eight weeks. The cold three months will slow down decomposition. The eight week warming phase should almost complete the decomposition and once the hot humid summer arrives the body is likely to be reduced to a skeleton. Insects and scavengers will obviously accelerate this process.
In fact, in an environment with high numbers of scavengers and insect infestations this could greatly facilitate the decomposition and result in a skeleton much earlier.
These are very ball park estimates.
[Answer]
It won't last a week.
You are basically providing an ideal environment for normal decay. It takes less than **7 days** for insects (mostly maggots) to basically skeletonize a human body (not counting some stringy bits), with the presence of larger scavengers it is unlikely to last even that long. On a normal tree it is unlikely to still be on the tree within a day or two, scavengers even insects can move a body around a lot, as will bloat and rigor. Without knowing the exact environment and wildlife it is hard to say exactly , but in a warm humid environment bodies do not last long.
[](https://i.stack.imgur.com/H4K3W.jpg)
[Answer]
**You can have it stay up there as long as your story needs it to stay up there.**
People sometimes climb up into trees and kill themselves. I remember reading about one such that winter hikers spotted. The body had been up there for years. I could not find that one again but here are others.
1. <https://www.dailymail.co.uk/news/article-2100499/Melissa-Joy-Dietzel-Decomposing-body-woman-30ft-tree-Sydney-missing-US-tourist.html>
Her body was up in the tree for 2 weeks. It was a populated area and people smelled it.
2: <https://www.bournemouthecho.co.uk/news/11404359.suicide-verdict-for-missing-21-year-old-found-in-tree-at-meyrick-park-golf-club/>
This body was in the tree for three years. In a park!
3: <https://www.telegraph.co.uk/news/worldnews/europe/germany/5098610/Skeleton-found-in-tree-29-years-after-suicide.html>
This body was a skeleton, found after 29 years.
---
Summary - if you want it to fall out after 3 days, fine. But decomposition is a lot slower up off the ground. Ants, worms and beetles access the body from the ground and a body on the ground will also stay moist which facilitates decomposition. Coyotes, armadillos and the like will not be able to get a body in a tree and depending how deep in the branches it is, vultures might not either. It is those big animals that pull a corpse apart.
What is left is insects and they will leave the skeleton intact. In your scenario, I suspect fly maggots will eliminate the soft parts while it is summer; that will also eliminate much of the ability of the corpse to hang on to moisture. Once the weather cools the insects die off and then what is left will desiccate in the dry cool winter. The desiccated sinews and muscles will hold the skeleton together and are not very attractive to scavengers. If you need it to stay up there lodged in the branches for decades, that can happen.
[Answer]
Europe used the [gibbet](https://en.wikipedia.org/wiki/Gibbeting) as a deterrent for various crimes, generally those which opposed the state or religious authority. Depending on how firmly your body is wedged in the tree, this may give a useful parallel with plenty of documented evidence.
Most of central and northern Europe will fall below zero in winter, and will not normally be so hot in summer. Still, it is worth noting [one example of gibbetting](https://en.wikipedia.org/wiki/Joseph_S%C3%BC%C3%9F_Oppenheimer) where the remains of the body survived in its cage for 6 years. Most likely it would have been fully skeletonised by then, of course.
There are also a large number of cases of slaves and pirates gibbetted in the Caribbean, and these are more likely to be comparable to your temperatures. I don't have the time to research these, but I'm sure you can find some fairly easily.
[Answer]
>
> As Sledge remembers: “It was gruesome to see the stages of decay proceed from just killed, to bloated, to maggot-infested rotting, to partially exposed bones — like some biological clock marking the inexorable passage of time.” – [artofmanliness.com](https://www.artofmanliness.com/articles/on-the-70th-anniversary-of-vj-day-eugene-b-sledge-puts-your-first-world-problems-into-perspective/) *On the 70th Anniversary of VJ Day, Eugene B. Sledge Puts Your First World Problems Into Perspective*
>
>
>
[Battle of Peleliu](https://en.wikipedia.org/wiki/Battle_of_Peleliu): 15 September – 27 November 1944 (duration: 2 months, 12 days)
My grandfather was only on Peleliu for two weeks before his amphtrack broke, and was from there after a stretcher bearer until he was wounded. He had similar anecdotes about 'explosive decomposition'.
That would bring the duration down to about eight weeks; your temperatures allow for six. I deem it extremely implausible that they would be, a) still in a tree, and b) recognizable.
] |
[Question]
[
We always assume first alien contact will be meeting with some strange looking alien, maybe with a multitude of limbs, sometimes with none, etc. etc..
However, so many of our Science Fiction stories talk about humans having strange bodies that have been manipulated at their genes and have other enhancements like cyborgs. One book I recently read was about humans that had 8 limbs, all arms, they wanted that for their work in space. Or gills for living on water worlds...
Why is it we can think that humans will manipulate their bodies to such extremes but aliens will all be homogeneous monsters that "scare" us just because of their alienness. I have to wonder for first contact if they would have specially designed bodies made for their ambassadors to communicate with us. I would think it might even help understand our frames of reference etc.
So assuming benevolence on the part of our first visitors how far might they try to modify their appearance (at least a few intermediaries) to communicate with us?
(I had a similar question before but it was poorly done, trying again and hope this is better)
[Answer]
**Odd-looking but Human-like robots**
In 2011, a civilization made first contact with a far more advanced alien species. As Samuel predicted in his answer, the contact took the form of a robot meant to mimick the denizens of the less advanced species.
The robot in question was RoboBee, [built by Tim Landgraf et al](http://www.newscientist.com/article/mg21128264.600-robobee-speaks-honeybee-dance-language.html#.VNDF2EZ0xaQ) in a bid to learn more about the bee's language of dancing ([2](http://doi.org/10.1109/IROS.2010.5650930)). Communication was one-way and only partly succesfull, yet a first-contact for the bees, in terms of communication. The experiment lends credence to the argument bowlturner makes under the above question, that aliens would mimick us to make themselves understood. In the case of bees, a bee-like body was essential to talk the "dancing language" of bees.
I am RoboBee, ambassador from the human race to lesser developed species.
I have made contact with the natives. They are receptive to my messages, but appear to be controlled by some kind of hive mind.
[](https://i.stack.imgur.com/bfhoa.png)
The mysterious builders of the robot watch from afar, unable to walk among the bees in their true form.
[Answer]
**They'll look like robots.**
It seems to me that the most likely method for first contact will be through an artificial intelligence. Our own best chance (at this point in history) for making first contact, to teach others about we humans, is through our space probes. Voyager 1 is currently more than [18 light-hours from Earth](http://voyager.jpl.nasa.gov/where/). Attached the Voyager probes are [Golden Records](http://voyager.jpl.nasa.gov/spacecraft/goldenrec.html), bringing a message from humanity to any space faring races who may come across them.
The vastness of space and the very solid theory that (effective or actual) faster than light travel is not possible (or at least not feasible) means that actual biological aliens are very unlikely to visit us. Just as unlikely as we are to visit them.
Suppose they sent a [generation ship](https://en.wikipedia.org/wiki/Generation_ship) or a cryo-sleeper ship. If they were coming here because they captured some radio waves or followed a probe back, they might know something about us and even what we look like. But because travel will take such long time, they couldn't even be sure we'd be the same when they arrived, or that we wouldn't have destroyed ourselves in the intervening decades/centuries.
**This leaves non-biological emissaries. Robots.** It's really the most logical method after sending a signal via light to let us know they're coming. The robots would come, hopefully with a measure of intelligence of their own. They would impart knowledge to us and ask nothing in return, as a benevolent race might do. Perhaps they could even bring some quantum entangled communication device, so that we may communicate with them in real time. It probably doesn't matter what they look like as long as we're just looking at a hologram. Modern humans can very easily accept what they're looking at if it's not in the room with them, we're used to seeing things that are not really there. This would be quite different for ancient humans, but then they wouldn't have a concept of benevolent aliens in the first place.
[Answer]
I would say this largely depends on their understanding of us.
If we go the route of thinking they've studied us for years and know things about our cultures and history. They may try to pick armor/holograms that depict benevolent forms. Ideas like this are explored in sci-fi all the time; Stargate has Thor (of ancient norse fame) belonging to a powerful race of aliens that are waiting for humans to reach a certain intellectual level. Displays and communication use the traditional image of Thor a norse warrior type figure with hammer in hand; however the alien is actually more typical of the "little grey men" appearance.
Other options may include: angels, greek gods, etc.
If on the other hand they're taking the blind approach to meeting us (following radio signals, but not really deciphering a meaning to them) then I suspect the dignitaries will be dressed in a way that shows status and respect befitting their own customs and traditions. We largely do this as well, our leaders dress in a way befitting their station for their culture.
[Answer]
Depends on who's going to define what "benevolent" means in this case.
For example if these aliens think for some reason that our way of existence is harmful to our "real" nature, they might want to "wake us" into the real reality by purging our illusionary world much like one wakes up a friend who's having a nightmare. So, in this case we might only see something upleasantly impersonal, like our sun suddenly becoming a nova.
It's also possible that they'd contact us telepathically, and we'd only meet after we've grokked each other.
[Answer]
**Benevolence is a matter of conduct not physical form.**
Ultimately if the aliens are benevolent (in the true dictionary sense of the word) their actions and the manner in which they introduce themselves and deal with us will reflect that.
Also if they truly are benevolent they must by default have (or will seek as quickly as possible to obtain) at least a basic knowledge of humanity, its history and human society. This is because otherwise they wouldn't know how to explain or display their benevolence. After all if you want to perform an act of benevolence for some random person you've just met you need to get to know them and their background before you can do so.
So as other people have suggested robotic go-betweens or even just non alarming digital images/avatars would do for first contact and initial introductions while the aliens themselves remain in space. Once language and communications routines become established the aliens would be explaining their intentions and while doing this they would also explicitly state that the images/machines are not their true form. Being quite upfront about that point. Then?
They just tell the truth i.e. that they're worried humans will think they're horrible monsters. So they start with some basic facts about their biology and physiology and an explanation of life forms back home with images (stills first, later video) of their environment plus diagrams, then stills and finally video of their actual selves. They break the news gently from a distance and then wait for an offer/request for a meeting from us before face to face contact occurs.
[Answer]
As @Wabbitseason said, it depends on what one means by "benevolent."
My definition of benevolent aliens would have them say hello by first deactivating all of our nuclear weapons and oil/coal/fission industry in an ecologically tame way, and then plugging our power grids into something green that gives practically unlimited electrical power, and then showing us how to stop destroying our planet in other ways, how to not have our endangered species go extinct, how to not be money-obsessed and not have people starve or be impoverished, how to be benevolent ourselves, etc.
So after some initial power outages and panicked media, we'd notice some television and Internet broadcasts where some people are explaining what's going on in a very friendly calm way.
They might look like attractive normal humans, because they'd create spokesperson images (or recruit actual receptive humans, such as the Dalai Lama), to look that way, so as not to alarm us, realizing from all the film broadcasts they'd watched from Earth, what our sensibilities are like. We communicate largely by face images, and they might not have a face, and even if they did, probably wouldn't have the same expression meanings, so it'd make sense to use a human-based image.
Or they might decide to avoid looking too human, and make or borrow an image like we've made for likable aliens in our sci fi films, or to carefully invent one that's like an earth creature, but that we haven't yet used to represent a fictional alien species, so we won't think of them like that fictional species.
Or maybe just send audio with visual of something nice like a blue whale swimming peacefully underwater.
Or they might mess up that second-guessing process, so the image might look like something from Zardoz or something:
[](https://i.stack.imgur.com/J5vZZ.jpg)
Or, they might decide not to do that, and show whatever they do look like (which could be all sorts of things), or they might choose not to show an image.
[Answer]
There are two important things that others have raised:
1. "This depends on the personality of the aliens." AKA do they have enough common ground to understand us and our standards or do they miss the point completely, like the alien invader in *[Never Send to Know for Whom the Lettuce Wilts](https://archive.org/stream/Fantasy_Science_Fiction_v102n01_2002-01_N602_DaisyChainsaw/Fantasy__Science_Fiction_v102n01_2002-01_N602_DaisyChainsaw#page/n5/mode/2up)*.
2."I would say this largely depends on their understanding of us." Even if they *can* understand us that doesn't necessarily mean that they *do*. Also humans are not a uniform group and we change over time a good understanding of the Papal States under [Alexander VI](https://en.wikipedia.org/wiki/Pope_Alexander_VI) wouldn't translate well in modern society. So called "Historic Truths" like "people only respect strength" could also be problematic.
I think there's a third point that I'm not seeing "What do they ultimately want?" Aliens looking for a market like Niven's [Outsiders](http://larryniven.wikia.com/wiki/Outsider) have very different motives to those looking for allies. Those motives will interact with the above to frame what they find an appropriate appearance in a first contact scenario. Merchants may wish to appear harmless, and keep on doing so in all contacts with us. Warrior cultures looking for allies are probably going to have to be more honest upfront.
Sorry about the formatting, I can't get the bullet points right for some reason.
[Answer]
Assuming they've chosen to specifically design a body to look friendly to humans, the first thing I'd do is not try to make it look like a human at all. While that is an approach that *can* work, it's also incredibly fraught, because what would be really minor differences from a non-human perspective can make it go from familiar to horrifying. Something as subtle as how exactly it moves can break it. If you steer away from human shapes, you won't accidentally fall into the uncanny valley.
To figure out a good form, they could look at human bodies, yes, but in a more abstract sense, trying to figure out what is aesthetically pleasing or comfortable about them, and collating that with animals humans like, along with art (though that's a bit dangerous if you don't know what kind of feeling the art is supposed to elicit).
Perhaps they'll find that they should favor soft shapes, and avoid things like spikes. Keep it simple enough, too - no head covered in a thousand eyes. And while we're on eyes, give it some. Two, specifically. Put them on its face. For that matter, *have* a face. Mouth, optionally a nose. Don't make it too human. The simpler they keep it, the less subtle pitfalls they face. Maybe it'll end up some kind of almost cartoony blob with a friendly face.
If they're not designing a body from scratch, they might just modify their natural body a bit following the same conclusions they find about what humans find comfortable. It's also possible their natural body looks just fine to humans as is. Even if they do look like eldritch horrors, which I wouldn't necessarily expect, it could still be fine: They're talking to us, they seem like reasonable people, sure they look horrifying, but I'm sure we can get over that. If they are really uncomfortable for human interaction, though, they might still want to do some alterations (since they're apparently quite able and willing) to make human interaction go more smoothly.
[Answer]
Unfortunately, I am afraid that your presumption that we always assume aliens will be horrific is largely flawed. In a huge, perhaps majority of science fiction, the key to first contact is a largely common human appearance. Look at the popular TV show "V". They were lizards but wore human bio-shells to look like us.
Another popular example of alien appearance modification for first contact would be Independence Day, where the aliens were tiny little creatures with huge robotic exoskeletons that looked menacing because they had studied us and knew what would scare us.
I think a large section of scifi deals with the notion that we are a primitive and barbaric species and that our first visitors either have been or are somehow evolved versions of us. This explains the almond shaped eyes, large heads, spindly bodies, etc. These are less likely terror-inducing, but more likely logical progressions of physical evolution and specifically evolution off the planet. When astronauts return from space, they are completely encumbered by their physicality--gravity sucks after even a short time without it. It stands to reason that creatures from space would have minimal bodies and large heads.
But to answer your question in another way: what makes you think that we haven't already been visited by aliens that knew enough about us to completely accurately blend in with us? It's likely more common of a theme that Aliens with the technology to travel to our planet will pick a physical appearance that is the most effective for communication with our species. Any attempt to appear frightening would only be the result of thinking that we would be barbarians and that frightening us would be the only way to control us.
But honestly, I like either the notion that we exist like fish (@Peter Masiar)--something that an alien society wouldn't even consider except as a novelty or pet. Or that the universe is much bigger and hugely more populated than we know, but with an interstellar group of "protectors" that placed us under quarantine in the universe until we develop to a stage that we are worthy of knowing the truth..or worthy of harvest like the next coming of Jesus Christ would be.
[Answer]
*This depends on the personality of the aliens.* No, seriously. Not every human thinks alike, nor dresses alike. Some humans wear tailored suits, others wear T-shirts. Humans have different goals, and present themselves in accordance with those goals. There is no good reason to think that the majority of intelligent species, or even highly advanced ones, would have a uniform approach to interacting with other sapient life-forms. A straightforward species, or straightforward members of a given species, might present themselves in their true forms, with whatever protection is necessary for the environment in which they find themselves. A deceptive species, intent on taking over without being noticed, would almost certainly take on human forms (unless they could control humans directly with a high degree of reliability). A species looking to be admired might look like attractive humanoids, or they might all be clones of Justin Bieber. A species that wanted to scare us might assume the form of a 300-foot tall tentacled squid-dragon-ape monster, but more than likely would be tall, slender, swarthy and sinister, buying up strange instruments of glass and metal and combining them into instruments yet stranger.
[Answer]
**They'd look exactly like the greys are usually described**
Assuming they really wanted to go the distance for fist public communications with a less advanced species, the aliens would want to appear similar enough to suggest a similar frame of existence and frame of mind to us while not looking so similar as to fall into the uncanny valley effect.
They'd also want to avoid wearing any adornments or equipment which could have ambiguous uses (dont look like you carrying a gun during first contact). In fact, if you have a genetically engineered ambassador class, you probably going to want them to be naked as a show of openness and vulnerability.
Finally, studies with animals have shown that as creatures get more sociable they tend to get larger eyes and whiter skin tones as these aid in communicating intent - where most other animals try to hide their intent.
Oddly, this leaves one with the popular description of short, naked grey aliens with enlarged heads and large eyes. Odd that -.-
[Answer]
I've always felt that a good approach for this would be, essentially, reverse-ambassadors. They would pick a small selection of representatives from the populace who could handle directly (or indirectly) interacting with them, and then use those people as representatives to sort of "pave the way" for eventual direct interaction. Assuming a wildly varied population (especially if it's a group of multiple different species, possibly enhanced as you say), it might be better to avoid confusion and/or overwhelming the poor lesser species.
A multi-step process beginning with local representatives might smooth things over. We see this all the time in reality, where a person who wishes to enter a group or organization seeks out a representative already in that group/organization to "make introductions".
[Answer]
If they are benevolent they would show up as themselves.
Hiding implies hidden purposes. Even if they are "for the good of the universe" they might inadvertently harm human interest. But look at all those shows featuring "alien-looking" alien superheroes like Ultraman and some of those Marvel or DC alien heroes--Most of them perform works of good as themselves. But look at the Alien X from Godzilla: Final Wars. They pretend to be human but are only monsters inside a humanoid skin. Humans get used to weirdness faster if the aliens are honest about who they are.
[Answer]
If, after the initial contact with humans, the aliens found their appearance to be repulsive, then for subsequent contacts, they may choose a human form. Only later, after establishing trust, would they reveal their true appearance.
[Answer]
You assume that sufficiently advanced aliens would be interested in interacting with humans. For me, it is far from obvious.
Imagine alien race which developed just mere 500M years earlier. They are as distant from us as we are distant from fish. Do we consider fish when you travel over water? Exactly.
And because rate of progress increases, after 500M years aliens would be much more different from even their own original form.
I do not think it is a stupid question. It is a **very serious question**.
Just our concepts/means of communication might be so off target that aliens may use that any meaningful contact would be nearly impossible. And only if aliens are benevolent, which is also far from guaranteed. @Abulafia made same point, but more humorous way.
] |
[Question]
[
DC, Marvel, X-men...etc style people, or things, exist. Great.
Now the existence of those people would definitely change laws and many legal practices. And of course the governments of the world would like to utilize the abilities of such individuals.
Only problem is this: How do you define a super person?
Yes. Superman or Thor or Hulk or Wonder Woman are clearly possessing of powers that make them super, good or bad is not the issue here. Iron man/Batman...etc are not. Being smart and rich and fit is not really a super power. They would be vigilantes. Most of those examples are clear.
But what about a person whose power is that they can turn slightly invisible? Translate all languages? really a good fighter like beyond the best we have. What about someone that is resistant to all forms of superpower but has no super powers. Like they can be mind read or moved by telekinesis...etc. What about someone who can see things in the past?
Basically those people are technically possessing things that are "supernatural" but not good enough to be in the same class of power/danger as the rest. It's clear.
But from a legal stand point we don't judge a person by that. Yes. In a particular trial we might. But laws and constitutions have a specific definition of a thing. Like house or car or human or chattel and so on.
This is super important since in my story there is a bit of a new world order. Super individuals are required to receive a special education, mandatory power training, can apply to special government agencies, and have special courts.
And like I said the complication is particularly obvious when it comes to territory of human limits. Breaking stone with your hands? Fastest running speed? Strength? Memory...etc.
**This leads me to ask how would the world and especially governments define a super person?**
Little extra.
Yes I'm aware that there would be different probable answers. But I feel the scope of the question is limited since we already have a more or less universal definition of a human. At least when it comes to actual practical laws. Which is what I'm constraining the whole issue to.
We also can all agree on the obvious cases, like the ones above. So. The question is more about what a group of law makers would propose as a definition of a super person?
In fiction we have a movie like Watchmen where it's not clear if anyone is super or not. Aside from Dr Manhattan of course. So. Again, this becomes about trying to figure out a clear definition.
And I'm not interested in anything else. This is not about evil governments exploiting people or how you can be useful without super powers...etc.
---
Every single country on earth has laws and clear definitions of things. And all of them agree on what humans are.
All I'm asking is what is the most likely definition that would be used to define a super person. Like if a bunch of law makers got together to amend the laws to include that, what would they come up with?
[Answer]
## Ignore the power; focus on the action
Let's look at two real-world people I know:
* Person A is an overweight middle-aged person of above-average intelligence and education with various chronic health issues who sometimes loses their temper and hits people in the head.
* Person B is an occasional ultramarathon runner with a couple of decades combined of military and civilian training in small unit tactics, pistols, rifles, light infantry support weapons, explosive demolitions, mine warfare and booby trapping, unarmed combat, fencing and archery. Person B is basically law abiding (other than occasional low-range speeding tickets).
The police have some concerns about Person A because even a blow to the head from even an unfit, untrained person can cause serious injury or death. The police have no real concerns about Person B so long as they pay their speeding tickets.
The simple fact is that in any country with a well-trained military there are going to be thousands of serving or retired members of the armed forces at or above Person B's level of training and these abilities make them *potentially* more dangerous than 99.9% of the general population. These people *could* use their training to undertake criminal and/or terrorist activities. However, any of the multitude of drone operators *could* endanger hundreds of lives by flying their drone into the controlled airspace around an airport, or any car/truck driver *could* drive their vehicle into a crowd of people they don't like. It doesn't take superpowers or even superior training to hurt or kill people, just readily available tools and either malicious intent or - far more often - negligence.
The sensible approach taken by most governments is to mitigate the negligence through mandatory training and registration (eg tests before granting a driver's licence and vehicle inspections to ensure equipment is safe) and prosecute people who do bad things. Trying to register and classify every possible "super power" would be like trying to register every person's "combat level" by tracking their current personal fitness, ranking and ability in any and all violence-focused sport (eg boxing, MMA, HEMA, ice hockey).
What would happen is that already-regulated activities would include people conducting those activities through super powers or super technology - it does not matter if a flying person is using an ultralight aircraft, a thruster powered suit or innate ability, they would need to conform to flight regulations over built-up areas and in controlled airspace. If violence is used by a person with super powers then the same legal standards that apply to everyone else would apply to the "super" - allowable self-defence is minimum force proportional to the threat, vigilantism is illegal. The same principles would apply to violation of any other existing laws, for example, hacking is illegal whether it is done with stolen passwords or a computer empathy super power.
(The question is about governments defining/classifying people, so I am deliberately ignoring the issue of trying to enforce rules on a recalcitrant Superman-level being. Similarly, the issue of how to detect that some super powers are being misused is out of scope - for example a person with clairvoyance or X-ray vision looking at an attractive person in their shower or bedroom.)
The only place that I would expect there would be a more rigorous classification of super powers would be in organisations that deploy super-powered people or anticipate actively opposing them, primarily military and intelligence. Military organisations would focus on combat and logistics abilities, spooks would focus on intelligence gathering and counter-intelligence abilities. Without far more detail on what powers exist and their frequency I am not going to propose a classification system - there would be very different scenarios if there are less than 100 "supers" worldwide compared to if 1% of the population has some level of superpowers.
[Answer]
The big questions are
**For how long has your world had superpowers?**
The longer, the more time they will have had to test solutions and figure out what works. Also, the more they will know about superpowers and such questions as whether a person who can be a bit hard to see will be able to develop the power further, or will just remain the same. The more clear the limits of a power are at first glance, the more likely that low-level powers can not qualify.
The shorter, the more clear-cut the definition: anyone who gained an ability that didn't used to be possible. But that may not prove useful.
The ideal solution would be to classify people according to the usefulness and danger of their powers. A longer term would give more time to sort this out, and also to find uses for powers. (You can generate diseases? Splendid, right this way to our vaccine development school, where you will learn to make vaccines.) Low-level powers will probably be sorted out of the system as neither, really.
They would classified into schools and programs according to what their powers are useful for. A person who grows plants is no more akin to a person who can turn invisible than a normal -- all three need different schools.
**How and when are powers gained?**
If you can tell when the baby's not born yet, you will have a much easier system than if anyone at any time could pick up a power when just walking down the street when something goes awry. Not only do you have to keep on classifying people, everyone's aware that they could fall under the classification at any time.
So it will be more rigid the earlier and more clearly you can distinguish such people.
[Answer]
I think people who have some minor ability wouldn’t even need to be classified. There are already people who are remarkably strong from bodybuilding, or extremely intelligent from genetics or neurodivergence, or people who can see broader spectra of light. They aren’t classified differently by the government. If superpowers became the norm, I don’t see how they’d be much different.
I think the government would only bother classifying superhumans who stood a direct threat to society, but that threshold is fairly open to interpretation. I can see this being a similar political debate to gun control, in a way.
It’s worth noting that super or no, vigilantism is usually illegal, so they might officially be “criminals.”
[Answer]
**Make Extremely Specific Classifications, and have a test for all people who reach a certain age. Anyone who exhibits traits that are beyond the government's strict definition of "normal" is thereby "super"**
World Governments and Organizations can solve the definition problem by being extremely specific with what constitutes "Super" or not. The best way to classify someone is to make a test for certain traits. Anyone that exceeds what the government considers normal is therefore classified as superhuman.
Tests could include basic things like Speed, Strength, and Intelligence tests as a baseline.
If you can lift more than X-amount of weight, then you are far outside the scope of human strength and are therefore super.
If you can run more than X kilometers in T seconds, then you are considered to have super speed.
An intelligence test is a much harder and more abstract, but if you are able to memorize thousands of images in a single sitting, calculate and multiply thousands of digits in your head without a calculator, or even more impressive feats, then you would be considered super smart.
Other anomalous abilities would be harder to test for, so the government would have to be creative and very thorough to avoid missing out on certain people.
To test for flight, you might ask a person to jump a certain distance in the air. To test for telepathy, ask them to read a person's mind and guess what cards they are holding from another room. To test for laser vision, ask them to stare at a piece of paper as intensely as possible. So on and so forth.
Obviously, you can't catch every power in a single go. If there's a wide variety of abilities you're always going to find one that's either incredibly rare or wholly unique. That's why I would suggest the governments should not only test for abilities but do so regularly and with great specificity.
Rather than classifying a human as "having no ability" it would be better to classify them as "having no ability that we know of yet". To the best of the researcher's knowledge, they could not find anything out of the ordinary with the person, but it might be something they have never thought of.
Obviously, there are going to be cases where there are false positives or false negatives, so the point of repeated tests is to make sure that the results are as accurate as possible, and the more scientists learn about the powers, the less likely they are to make a mistake.
Sometimes an ability will be so rare or unusual that it will fall outside the previous guidelines, or it is so specific that it's nearly impossible to scan for. For example, what if an ability only comes out when a person is in a life or death situation. It would be unethical to risk someone's life to test them for that, so what if you show them a jumpscare from a movie or something like that? A slightly more extreme idea would be to give people an adrenaline shot to trick their bodies into thinking they are in danger, forcing any latent ability to activate if it is indeed activated by fear.
That would be an example of a false negative. A person is super, but they didn't show anything on the test. Legally, they are not super because they have no ability on record. While they might have something hidden, the government has decided they have nothing unusual about them.
A false positive would be a person who is either "peak human" or someone who passed the test either through strange happenstance or purposeful rigging.
By peak human, I mean a person who manages to, by sheer force of will and training, pass all the tests that they are given. They passed the strength and speed test through a near Olympic level of training, and they have a genius-level intellect they have honed through study and effort. They may never be able to achieve the feats of people who have superpowers, but they are immensely impressive in their own right.
The test could also go wrong either through accidents or manipulation of the results. A family of superheroes might not want to admit that their precious child has no abilities, so they bribe all the judges to have them right down that their child is in fact super. Or, a person could pay a superhuman to either pretend to be them for a day or act from the sidelines, either feeding them the results they need through an earpiece or using their powers to intervene. A telekinetic, for example, could make their friend pretend to fly for a while.
No system is perfect, and there are definitely going to be super individuals who slip past the notice of the system. There are also people who might be able to pass through sheer luck, remarkable strength, and talent, or by playing the system. Such people would be considered "super" even though they are not in actuality. Money could very well be a superpower if a judge can be bribed with some crisp hundred dollar bills.
Honestly, I love the idea of a person being able to earn the title of "super" through being an Olympic level athlete, a math prodigy, or a remarkably skilled musician, or any other vast talent that they could have.
So, what classifies a person as super? Whatever society or the government says it is according to their guidelines.
The idea and classification might be different between countries or even cities. It also might be suggestible to have levels such as S, A, B, C, and so on.
C is the lowest level. It is also referred to as the "common" level. You might have a power but, as far as anyone is concerned you are considered indistinguishable from a normal human being. Humans are lumped into this category too.
B is the next highest. If you're an Olympic level athlete or math genius, you might be able to get here, but you'd have to be incredibly talented.
A is even higher than that. The things they can accomplish are far beyond anything a normal person could be able to do.
S is even farther up the ladder, seeming mostly godlike to people of lower levels.
*There might even be a world ranking system*
Every person in the world could be given a certain "score" based on their tests, used to determine what their overall ranking as a superhuman is.
The person with the highest score is therefore on record as the most powerful person on the planet. This score is both an honor and a burden, because it means that person is arguably the most dangerous person alive.
[Answer]
# Rank each person from 1-10.
Each person will be ranked from 1-10. They'll be ranked on what is the minimum you need to handle them.
1 is someone with a power that's a threat to a untrained person.
2 is a threat to a trained professional.
3 is a threat to a team of professionals.
4 is a threat to a team of professionals with specialized countermeasures.
5 is a threat to a team of professionals with specialized countermeasures and a single super.
6 is a threat to a team of professionals with specialized countermeasures and a single trained super with special countermeasures.
7 is a threat to teams of specialized supers.
8 is a threat to a city, and needs multiple teams of supers to handle or heavy artillery.
9 can't be handled by normal supers, and should be avoided where possible. Elite supers and a specialized plan is needed to handle them.
10 evacuate where possible, and don't engage without approval from the white house.
# They can be ranked on these scales.
Brute. Enhanced strength or toughness.
Thinker. Enhanced intelligence or precognition.
Mover. Enhanced speed or movement.
Tinker. Mad science creation beyond normal physics.
Shaker. Extremely wide area of effect.
Blaster. Long ranged effects.
Trumps. They alter the nature of powers, enhancing, removing or modifying them.
Master. Mind control or minion creation.
Changer. They alter their shape or form.
Stranger. They have some stealth or infiltration powers.
This gives you a good quick estimate of their abilities, and a good common reference as to how to handle them.
# Examples
Someone like Batman or Iron man would have tinker abilities. Anyone who can build body armor centuries in advance of science is clearly supernatural beyond normal means. There's gonna be a strong interest in recruiting them.
Let me give you a few examples of common superhero rankings.
Iron Man. Tinker 7. Brute 4. Mover 4.
He's pretty impressive physically, and very good at inventing things.
Batman. Thinker 6, brute 5, tinker 4, stranger 6, trump 7.
He's very stealthy, very smart, very tough, and has a lot of super tech. He has counters to common superhero powers somehow and has taken down the justice league.
Anyone at 3-4 is likely going to be required to register and serve. Someone who is dangerous to a team of professionals is the equivalent to a loaded rocket launcher. You don't let them out in public without training. People with useful but less dangerous powers like universal translation will be strongly encouraged to serve, but not forced.
They would likely use a mix of common sense and their judgement of your powers. No two powers are necessarily alike. They need to guess.
[Answer]
***Boring medical answer***
Well, it really depend on the source of those power. but for X-men for example, if i remenber well and it have not been retconned, it is a gene that give power. so therefore the line can be cut and dry "you got said gene, your a super". And you can immediatly screen baby born out of super familly.
yes it would require a real effort to ramp up testing as the new world order is established, but then you would just have to screen newborn.
also, if somebody is latently showing power you don't have to test them, just stamp it by default.
***How does magic work?***
but what interest me especially for those scenario is how power manifest themself. because there is no good explenation i remenber seeing about why some human can sudenly get magical power, as it is certain those power aren't linked to the biology, especially as most of those power violate so many law of. so there must be something that human can tap in to get those power working, and with some R&D you might just find a meter that at worst can detect you taping into those power, or even mesure just how much you can pull in.
then, you might put a treshold.
***What if science fail***
If you can't mesure power or gene at a widescale in a rationable way, you will have to resort to good old human judgment. And i think it is not incompatible with the other idea
A good factor would "disturbance factor" somebody who can change the color of his skin to nice but flamboyant color might very well be a mutant but is it really worth classigying him as such?
what should really matter and could be a category in its own is "disturbance/danger" potential and the amount of control they have.
the controle part is easy, how manageable the power is. if you can't help but be on fire 100% of the time, you can't help it and get a 0 in controle, reducing your liabilty or outright removing it from a lot of thing. if you just need to take a anger management class to not pull out your claw you get a 5 and anything linked to your power is assumed. in between notation would be for power that have colateral effect. or other effect that you can less controle. in those case you would need permit & authorisation to use
for the disturbance part on a scale to from zero to five:
0 would be no aplicable use (ie mild cosmetic change linked to the mutation) those are people you might classify as non mutant. if you just have a third eye you don't need special law for that.
1 Human plus.you are still mostly human, but you got a quirky thing, like having a preshensile taile or wings. it give you a bit of an edge over a human, but you are still very much bound to the same reality
2 you can kill a person with it. any power that give you a real weapon available at any time or that can kill somebody easly is threat 2.
3 Material damage, peace disturbance, supernatural. this is a bit of the "put it all in" category. those are all the higly unnatural power that are fare exceding human capacity.Even if the power doesn't seem too powerfull at first glance, as it is far beyond human reach you need to monitor it in case the mutant can find a nefarious use for it. teleportation for example is a threat 3 because the nefarious potential of such power is huge, but at face value, you probably wont see this guy drop skyscraper on people. this category include all passive effect that will impact people out of social distanciation range with you. even if it's just making them sneeze , if your precense is enough to affect people you are higly disturbing to society
4 mass destruction potential. if you got out of control, you might level a block on accident. think of any power that you would say "imagine if the military could do this". it doesn't need to be dangerous to the whole city, but as long as you can blow up a house without too much effort, it goes there
5 country/worldwide threat. those are your doctor xavier and magneto. they got power that could qualify as godlike, and if used in nefarious way could spell doom for humanity as a whole
a few example:
-cyclope: 4/5 Disturbance, 0/5 controle. he can level down a block if his sunglass fall of his nose and there is nothing he can do about it.
-docteur xavier: 5/5 disturbance, 5/5 controle. with their power they can be a threat to society as a whole, but it is entierly in their controle
* wolverine 2/5 disturbance, 5/5 controle. he is packing weapon everywhere, but it doesn't force him to much
-mystic 3/5 disturbance, 4/5 controle. shapeshifting can cause huge amount of trouble, and she loose a point in controle as not using her power force her to have this strange apearance.
with all this you can have regulation that aplie to different level of power.
[Answer]
As authors or audience of speculative fiction, we would define "super" as "a person who can do something that's impossible in the real world". But the fictional world, there is no "real world" to compare to. For the characters, their world is as real as it can get. So when so-called "superpowers" are part of the world, then from the perspective of the characters there is nothing "impossible" about them. Some people in their world just *can* throw cars and fly.
So let's forget about the distinction of "humanly possible" and "humanly impossible". In a world where superpowers are common, that's no longer a meaningful distinction.
But fact is, there are some people in the world who can do stuff the vast majority of people can not, and that makes these people interesting and worth tracking. So how could we define those super individuals? **By simply stating "someone with a one-in-a-million ability is a super"**. When you can fly, and less than one in a million of people can fly, you are a super. When you can lift more than one in a million people, then you have super strength.
This might put some people into the "super" category who would probably not classify as "super" according to our real-world standards. Like a math prodigy who is better at mental arithmetics than one in a million people. Or an olympic-level athlete. But from the perspective of an inhabitant of this fictional world, this difference might not actually be apparent. Why would a world which recognizes *Hawkeye* and *Batman* as a super not recognize *Usain Bolt* or *Gari Kasparov* as super?
[Answer]
I would think this proposed scenario would eventually (d)evolve into nearly the same situation as outlined in Kurt Vonnegut's "[Harrison Bergeron](http://www.tnellen.com/cybereng/harrison.html)" - government, being government, institutes a "*Department of Equality*" (or some something equally 1984-esq) and spends all resources "leveling the playing-field" by ensuring everyone's talents are handicapped.
[Answer]
### The Legal Question
Firstly, a legal definition of a "super" will depend on the framework of the laws that require it. No government will define what (or who) is a super just because they want to -- There will some legislative need to define the term formally. Be it at a national level or a world treaty level.
The first big question is what is the purpose for this? Based on the question, it looks like the aim is to ensure that supers do not pose a casual threat to the unpowered humans. My suspicion is that such a system is born from a rise in superpowers in general and the unintended consequences of powers running amok. I also suspect that somebody with a uncontrolled and dangerous power caused a lot of damage unintentionally back in the past, solidifying the need for such a set of laws. Or somebody did this on purpose and there was no suitable framework to handle it.
### Defining the Super
There are four parts to what Supers get in your question: special education, power training, extra opportunities to work for the government, and special courts.
The third, government work, we can exclude from this -- while a super can get these jobs based on abilities they possess, it is more like an extra skill that gives them a leg up. Unless there are worldwide treaties that set aside area for super vs. super battles, that they are a super is less important than their possession of a unique ability that the government can make use of.
The other three points seem to point towards the definition of a super being **the possession of some manner of extraordinary ability that can potentially cause harm to the populace at large beyond a set threshold**.
### Defining the Definition
Sounds odd that one has to define the definition of what a super is. But the question then becomes when does an ability cross from ordinary to extraordinary? What are the thresholds of ability that create the line between Mundane and Super?
**First check**: Are supers genetically different from the mundanes, like the X-Men? If yes, then the definition would include the concept of an "*active genetic marker or makeup that causes superhuman abilities*" in it. It wouldn't matter if your power is harmless or not, if you have the marker and it is active, you are on the list. Alien biologies that cause superhumans in our world, such as Superman would also fall into this category, though possibly under a different technical definition.
This check is the most precise as it relies on a physical constant of the body -- its very genetic makeup. Magical beings that have a physical difference such as werewolves and vampires likely fall under this as they have defined physical makeup differences.
**Second Check**: Is there some kind of standardized testing that can be done to determine extraordinary abilities? If so, then the definition will include the concept of "*abilities learned or expressed beyond a standard human threshold*". If you have learned to do something a regular human cannot, then you're on the list.
A general case here is magical potential -- ones genes or family predilection might say that a person can use magic, but if they never actually study it or manifest it in some manner, then should they count as a super? Other energy-based skills also fall under this, such as martial artist ki abilities
For physical abilities, the premise will be that anything beyond a specified threshold of ability will be considered a super. These are thresholds that will have to be adjusted as the world around them changes -- not just the supernatural parts of it, but also the mundane.
This check will be trickier unless there is some consistency in the powers or power sets exhibited by the population at large, or an ability to measure them despite people trying to suppress them to avoid the designation. Not necessarily consistent in actual ability, but in how to learn and/or acquire them.
**Third Check**: Does a person regularly make use of technology to take part in the super society? If so, then the definition will include the concept of "*utilizing external means to achieve superhuman abilities on a regular basis outside of designated environments*", or something like that.
This covers the Batmans and Iron Mans of the world -- those who are only super because they use tools and have actively decided to take part in the super world. They will be the trickiest to legislate because they effectively are part-time supers unless they have decided to fully embrace the super life, with all the perks and drawback that such a decision entails.
The tricky part here is that some jobs, government and mundane, may have their workers use things that would qualify them as supers under this check. That is something else that will have to be dealt with.
There are more granular ways to go into those details, but those are likely the three main ways that people would be considered "super". The exact nature of the world will determine which options apply and how best to determine them.
### Classification of Superness
This has been gone over, but it bears mentioning because of the laws around supers and your particular goals for these definitions. It will be up the lawmakers, and their special super consultants (may be actual supers), to determine if a super and/or their powers needs to be categorized beyond the fact that they are one.
This will mostly depend on the power level disparity that exists in your world. While any sufficiently creative mind can find clever uses for any power, it can be agreed that making a small object/area slippery and being able to control the weather in a several mile area are different levels of power. Nothing you have stated in the question suggests that a classification of powers is necessary.
* All supers need to take the classes to know their rights, obligations, and laws that relate to being a super. Included are the laws mandating super/mundane relations.
* All supers need to make sure that their powers are under control at all times, with mandatory training to ensure that it is under control -- not unlike some countries' firearm laws really.
* All supers have special courts because lawyers and judges for supers need to take special powers/abilities into account when adjudicating cases and remain unbiased as they do so. Not to mention, the courts need to be able to physically survive emotional outbursts from potentially unstable supers.
Any classification of a super will more be a general assessment level of ability so as to determine what an individual needs to do to comply with the laws of the land. Others have given better insight into this part than I could, so I would refer you to their answers for that should you choose to go that route.
### Conclusion
Defining a super is going to be a highly technical and precise process. The common person may boil it down to a few sentences, or like our answers to a few specific points. The actual legal text may be ponderous and full of caveats, exceptions, loopholes, and patches for things found after the laws were drafted.
This does not even get into the potential human rights issues and can of worms that can be opened by such a set of laws, even if those making the laws have good intentions and the well-being of all citizens in mind.
[Answer]
## Decision on a Case-By-Case Basis
As pointed out by other answers, defining a superperson is hard. Even if there is a universal definition, proving that someone fits that definition is not straightforward. So your NWO government has a Department of Superpersons. Someone who exhibits a potential superpower has to apply for a Superperson status. After filling a mountain of forms, doing a bunch of tests and months and months of waiting, the DoS may approve your application. You then get a stamp in your ID document that grants you access to special education, courts and whatever else.
If a Superperson status is desirable in your society, if it gives such an individual privileges that other people do not have, this should work well.
[Answer]
As it's your story you write the rules. So why not make superness a simple detectable test? You get your DNA analysed at birth if you've got the super-gene then training is made available when you start school.
The whole idea of a power scale is much too limiting when we think in an [Eigen Plot](https://tvtropes.org/pmwiki/pmwiki.php/Main/PlotTailoredToTheParty) manner. Sure maybe my only power is to make surfaces slightly slippier, but my number of assassinations via falling down the stairs in public is notching into triple figures.
[Answer]
## They'd leave it to a committee
Every criterion listed on this page will be used at some point. The committee will change its criteria after every election, every scandal, and according to fads and legitimate research in academia.
The criteria will be poorly applied by a bunch of bureaucrats using guidelines full of subjective words. In the end, it'll be nearly impossible to give an answer beyond, " If you can do amazing things, you may be super, and the ministry will evaluate you".
Attempts to put the whole business on a sensible footing will simply add to the mess of competing local, national and international standards, and implementation thereof. People will write standards that seem to offer answers but actually assume perfect knowledge and/or infinite time and budget. ISO9001 will cost a fortune and despite decades of 'continuous improvement', nothing will improve.
If any sort of international standard ever does come out, the USA won't sign up. China and most third world nations will but will then renege and have even lower real standards than the US's low national ones. The EU will both sign up and apply them all but take 54 years to translate them and implement them and make them so volumnious and full of political concessions that you'll be back to square one. It'll collide with CAP. I don't know how but it will.
We live in a society that doesn't have a clear definition of 'rich', 'poor', 'smart', 'stupid', 'good', 'bad', 'child', 'normal', or even increasingly 'man', or 'woman'.
What on earth makes you think they'll successfully define 'super'?
The one thing you can count on is that Bruce Wayne and Tony Stark will end up classified with the classification they want, because they're loaded.
] |
[Question]
[
If I wanted to image an Earth-like planet at a resolution where one could read the lips of a human speaking on the surface 1, 10, and 1000 light years away, how large would the telescope reflector need to be (the diameter) in each case?
Another way to ask my question is: Given a parabolic mirror/reflector the size of, say Earth's orbit, what would be the farthest distance one could read someone's lips or read printed text (a secondary concern would be imaging the entire face of the planet at such resolution)?
Assume the telescope is in space (no atmospheric interference) and outside of any asteroid belts or dust clouds, etc. I understand the mirror would have to track the movement of the planet.
My main objective is to get a layman's grasp of the relationship between the size of a telescope's reflector and its ability to see small details very far away. How big of an image can it produce and at what level of detail?
[Answer]
When talking about telescopes there are two quantities to take into account; the “light gathering power” and the “resolving power” of the telescope. “Light gathering power” is just how much light can be collected by the telescope. “Resolving power” is a measure of the smallest angle that the telescope can reliably detect.
Because light is a wave it has a way of spreading out (technically: diffracting). The smaller the telescope the more the waveness becomes a problem.
What’s a little weird is that this isn’t just limited to the size of the mirror or lens of a single telescope. By cleverly networking telescopes together you can make them act like a single large telescope.
Visible light has a wavelength of about half a micrometer (one two-millionth of a meter), people are about a meter across (assuming a spherical person), and the Earth is about 13,000,000 meters across. So, using ground-telescopes that are perfectly constructed and networked, we could spot something person-sized from about 1/400th of a light year away, or about double the distance to Pluto. For comparison, the distance to the nearest star is about 4 light years. So, using ground based telescopes we can’t come even remotely close to seeing a person standing around on a planet in another solar system.
The nearest known, reasonable, candidates for being an Earth-like planet (as of April 2013) are about 20 light years away (HD 20794 d, Gliese 581 c, and Gliese 667C c). Spotting dudes and ladies on one of these worlds requires, at minimum, a telescope array that’s at least 100 million km across. That’s an array more than half the size of Earth’s orbit. The good news is that an array like that (under absolutely ideal circumstances) isn’t that difficult to create. Setting aside that the telescopes would each need to be essentially perfect for their size (Hubble-quality), all we’d need to do is set them up in solar orbits about the size of Earth’s orbit. This is a lot easier than sending them to another planet, and about as hard as sending them to crash on the Moon.
So, assuming that we could set all that up, the problem stops being one of resolving power, and becomes one of light-gathering power.
On a sunny day we’re hit by about 10^21 (1,000,000,000,000,000,000,000) photons (give or take) every second. Assuming that a fair fraction of those escape into space, then that number, which seems large, is all that distant aliens have to work with. Over 20 light years that scant 10^21 photons means you would need a telescope array with an area of more than 500 million square kilometers to catch just one photon per second. That’s the size of the surface area of Earth. In the mean time there’s a lot of other light flying around, and single photons are pretty hard to detect so… the signal-to-noise ratio would be small.
Creating an array capable of seeing big stationary things like rivers and mountains on other worlds wouldn’t be too difficult, because you can just use tremendously long exposures to overcome the whole light-gathering issue. This is a pretty standard trick in astronomy; the Hubble Deep Field took a more than a week of total exposure time. There would be some issues with the fact that those distant planets are moving and whatnot, but there are clever ways around that too.
People, and probably aliens too, move around a lot. So if you want to get a picture of one, you need the exposure to take less than, say, a second. Unless you catch E.T. literally napping. I would wildly guesstimate that you’d need at least a few thousand photons per second to overcome the signal noise enough to say for certain that you’re looking at something real.
So, to answer a somewhat more detailed question; to get a picture of an alien that’s person-sized, standing on a world 20 light years away, so that it takes up one pixel in the image, using an exposure time of about one second, would require an array of telescopes with exposed mirrors and lenses with an area totaling more than several thousand times the Earth’s surface area and spread out over a region about the size of Earth’s orbit.
This isn’t technically impossible, but it would be “expensive”, and would require substantially more materials than are likely to be reasonably found in our solar system. It probably isn’t worth it to get a blurry, tiny picture of some alien picking its nose 20 light years away and 20 years ago.
Of course, if you wanted to see farther, you’d need a much larger telescope array.
[Answer]
### TL;DR: Depending on the fidelity of video you want to shoot of the aliens, you can be limited either by diffraction (low fidelity) or photon counting (high fidelity). Overall, the numbers are really large though. For example, the telescope radius for doing lip reading at a distance of 1 lightyear (~ 63000 AU) is roughly ∼92 AU (!). With a 1 AU telescope, you can do lip reading for folks ~700 AU far away.
# Key result
To shoot video that resolves a length scale of $d\_\alpha$ at $60 \text{ fps}$ with decent color accuracy (8-bit RGB, error rate < 1/10)
when the alien star is sun-like and the system is at a distance $\ell$ from the telescope,
the telescope radius $r$ is bounded below due to photon counting considerations by:
$$ r\_{\text{min}} \simeq \frac{\ell}{2d\_\alpha} (7.27\times 10^{-6}\text{ m}).$$
If one relaxes the demands on the video fidelity, the limiting factor becomes the diffraction of red light:
$$ r\_{\text{min}} \simeq \frac{\ell}{2d\_\alpha} (6.20\times 10^{-7}\text{ m}).$$
# Answers
>
> If I wanted to image an Earth-like planet at a resolution where one could read the lips of a human speaking on the surface 1, 10, and 1000 light years away, how large would the telescope reflector need to be (the diameter) in each case?
>
>
>
Say we want to do lip reading. The size of a human mouth is about $5\text{ cm} = 0.05\text{ m}$. Suppose we assume that if we have a video where your mouth is about 20 pixels wide, we can reasonably do lip reading (the vertical direction has the same scale so no worries that lips will look too thin). Then $d\_\alpha = 0.05/20 = 0.0025\text{ m} =2.5\text{ mm}$. So for the first question, the telescope *radius* for doing lip reading at distance of $\ell = 1 \text{ lightyear}$ is roughly (using the first formula) $1.4\times 10^{13}\text{ m} \sim 92\text{ AU}$. For comparison, the radius of Neptune's orbit is about $30 \text{ AU}$. So our telescope has to be really big!
>
> Another way to ask my question is: Given a parabolic mirror/reflector the size of, say Earth's orbit, what would be the farthest distance one could read someone's lips or read printed text (a secondary concern would be imaging the entire face of the planet at such resolution)?
>
>
>
One can similarly answer the second question. For that, you plug in the telescope size $r = 1\text{ AU} = 1.5\times 10^{11}\text{ m}$ and the same $d\_\alpha = 2.5\text { mm}$ as before. This gives the distance to be $\ell \sim 10^{14}\text{ m} \sim 700\text{ AU}$. You can see that this is about 23 times the radius of Neptune's orbit.
Imaging the full planet at this resolution is not an issue -- all we are doing is replacing a small telescope (like the Hubble) with a huge telescope. This does not decrease our field of view (physical size represented by picture) but it does enhance the resolution (sharpness of picture) and imaging fidelity (correctness of picture).
>
> My main objective is to get a layman's grasp of the relationship between the size of a telescope's reflector and its ability to see small details very far away. How big of an image can it produce and at what level of detail?
>
>
>
You can tweak the level of detail and image size (I assume you mean pixels) by adjusting the parameter $d\_\alpha$ by considering the following: imagine a digital photograph of the object you want to actually image. Calculate the appropriate $d\_\alpha$ by dividing the physical length of the object by the minimum width of the "imaginary digital photo" (in pixels) at which the object is clearly identifiable. Basically, $d\_\alpha$ is the physical size corresponding to 1 pixel width.
# Cosmic videography theory (CVT)
## Pursuit - Speed, color and pixels
Suppose we want to shoot the video with a minimum time-scale of $\delta t$.
For example, if you want to shoot slow-mo at $200 \text{ fps}$ then use
$\delta t = 1/200 {\text{ s}}$. We would like to record RGB values on a linear
scale with 256 divisions, where each channel is defined by a pair $(\lambda\_X,\epsilon\_X)$
($X=R,G,B$).
The ease of resolution will depend on how small of a background you have.
This is common sense -- you can see many stars at night and only the sun during the day.
For simplicity (and best performance), assume that our sun, telescope and alien
are in a straight line (in that order). We put stuff between the sun and the
telescope to (effectively) block out all the radiation from the sun.
For example, you can use lead blocks to block $\gamma$ rays etc.
In principle, it is possible to have zero background if your resolution
is good enough and your detectors have no noise of their own
(super chilled, superconducting, super everything) so let's stick with that.
You can get rid of the background but you cannot get rid of [Rayleigh's criterion](https://en.wikipedia.org/wiki/Angular_resolution).
Let the diameter of the alien subject be $d\_\alpha$, the radius of our
Peeping Tom Telescope Array (PTTA) be $r$ and the distance to the alien
subject be $\ell$.
$$ \frac{d\_\alpha}{\ell} = \theta \geq \frac{\lambda\_R}{2 r} \implies
r \geq \frac{\lambda\_R \ell}{2 d\_\alpha}$$
where we used $\lambda\_R$ as it is the largest wavelength out of the three
and hence needs the largest PTTA.
As pointed out in @SandyBeach's nice
[answer](https://worldbuilding.stackexchange.com/a/70700/37356),
we need to consider both resolution and exposure. We have already
discussed resolution, we now proceed to counting photons.
## Intro - Photon generation and redirection
Definitions: power = energy per unit time, intensity = power per unit area,
intensity spectrum = intensity per unit wavelength,
flux = number per unit time,
flux density = flux per unit area,
flux density spectrum = flux density per unit wavelength.
The intensity spectrum $dI(\lambda)/d\lambda$ of the alien's sun is given by Planck's law;
we can use this to get the flux density spectrum $d \sigma\_\Phi(\lambda)/d\lambda$
using $I = E(\lambda) \sigma\_\Phi = hc \sigma\_\Phi/\lambda $ for photons:
$$\frac{d P(\lambda)}{d \lambda} = \frac{2 hc^2}{\lambda^5}\frac{1}{\exp\left[\frac{hc}{\lambda k\_B T}\right]-1}
\implies
\frac{d \sigma\_\Phi(\lambda)}{d \lambda} = \frac{2 c}{\lambda^4}\frac{1}{\exp\left[\frac{hc}{\lambda k\_B T}\right]-1}$$
The total flux density is $\Sigma\_\Phi = \int\_0^\infty \frac{d\sigma\_\Phi(\lambda)}{d\lambda} d \lambda$. Similarly the fraction of
flux density in a window of wavelengths $(\lambda-\epsilon,\lambda+\epsilon)$ will be
$$f(\lambda, \epsilon) = \frac{1}{\Sigma\_\Phi} \int\_{\lambda-\epsilon}^{\lambda+\epsilon} \frac{d\sigma\_\Phi(\lambda')}{d\lambda'} d\lambda'.$$
Suppose the subject of our video is illuminated by a star and has a response function $\alpha(\lambda)\geq 0$, i.e.,
if the incident flux is $\Phi(\lambda)$ then the outgoing flux is omnidirectional (to first approximation)
with magnitude $\alpha(\lambda)\Phi(\lambda)$. Assuming that the subject is not on fire, $\alpha(\lambda)\leq 1$.
If the subject is blue in the face, then $\alpha(450\text{ nm})\simeq 1$ and $\alpha(600\text{ nm})\simeq 0$.
If the subject is a mango, then $\alpha(450\text{ nm})\simeq 0$ and $\alpha(600\text{ nm})\simeq 1$.
**Note:** We ignore atmospheric effects (on the alien planet) which may alter the spectrum in a [nontrivial manner](https://en.wikipedia.org/wiki/Sunlight#/media/File:Spectrum_of_Sunlight_en.svg).
## Incident - Poisson statistics
In an ideal scenario, the RGB values recorded would correspond directly to
$\alpha(\lambda\_X)$. For example, if the scale is from 0 to 255, then we
would (ideally) record R=0 if $\alpha(\lambda\_R) \leq 1/256$, B=255
if $\alpha(\lambda\_B) \geq 255/256$ and so on.
However, the minimum of the three $f(\lambda\_X,\epsilon\_X)$ values is a bottleneck for
measurement. Why? Since our fluxes may be small, we must apply [Poisson
statistics](https://en.wikipedia.org/wiki/Poisson_statistics) instead of taking
a uniform flux. The flux density of the star
$f(\lambda\_X,\epsilon\_X)\Sigma\_\Phi$ is related to the incident flux
on the alien subject by a wavelength-independent geometric factor, say $Z$, so
$\Phi(\lambda\_X) = Z f(\lambda\_X,\epsilon\_X)\Sigma\_\Phi$.
Then the expected flux in channel $X$ in the time $\delta t$ will be
$$\mu(\lambda\_X) = \delta t\cdot Z\_T \alpha(\lambda\_X) Z f(\lambda\_X,\epsilon\_X)\Sigma\_\Phi$$
where $Z\_T = \pi r^2/(4\pi \ell^2) = r^2/4 \ell^2$ is an additional geometric factor and (like before)
$r$ is the radius of the PTTA and $\ell$ is distance from the PTTA to the subject.
The probability of getting a count of $k$ will be
$$P\_X(k) = \frac{\mu(\lambda\_X)^k e^{-\mu(\lambda\_X)}}{k!}\quad k = 0, 1, 2,\ldots$$
As long as the subject is not too dark (i.e. small $\alpha$ for all $\lambda\_X$), we can
approximate the Poisson distribution by a Gaussian of mean $\mu(\lambda\_X)$ and standard deviation
$\sqrt{\mu(\lambda\_X)}$:
$$P'\_X(k) = \frac{1}{\sqrt{2\pi \mu(\lambda\_X)}} \exp\left[-\frac{(x-\mu(\lambda\_X))^2}{2\mu(\lambda\_X)}\right]$$
[](https://i.stack.imgur.com/3o5sR.png)
Graph showing fit of Gaussian (line) to Poisson distribution for mean values $64,128$ and $256$.
## Reasoning - The Measurement Process
Let us now discuss the actual measurement process.
Naively, one would think that $\mu$ should at least be $256$ for
$\alpha = 1$ so that the full color range of 0-255 is used.
In a time step $\delta t$, count the photons and assign the value
to the corresponding color. However, the counting statistics make this complicated.
For example, if $\alpha = 0.5 \leftrightarrow \mu=128$, it is
quite possible that the actual counts observed in successive time steps
will look like {120, 133, 131, 125, 134} (because the Gaussian standard
deviation is $8\sqrt{2}$) and therefore the $\alpha$ value
will be incorrect at all the five time steps. ☹
### Special Investigation - A quest for better color reproduction
Suppose we have a tolerance $p$ for errors ($0<p<1$), i.e., at most $Np$ out of $N$ measurements are incorrect.
We demand that this condition holds separately for each bin from B=0 to B=255 and similarly for G and R.
Without loss of generality, let the alien's sun have $f(\lambda\_B,\epsilon\_B)$ as the least value
out of the three. For simplicity, let $m=\mu(\lambda\_B)$ when $a(\lambda\_B)=1$, so $m$ is the maximum number of
"blue photons" received in an interval $\delta t$ (as $a(\lambda)\leq 1$).
As shown above, it is clear that having the value $m = 256$ will not satisfy $p<1$ as most results will be
erroneous. Therefore, $m$ has to be much larger than $256$. In that case, the B value as a function of
count $n\_B$ is set using
$$ B(n\_B) = \begin{cases}
\mathrm{floor}(256 n\_B/m) & 0\leq n\_B < m \\
255 & n\_B \geq m
\end{cases}
$$
(We will account for the error due to the truncation in our simulation.)
Using a larger average value will reduce our relative error:
[](https://i.stack.imgur.com/mYR9x.png)
This graph shows the reducing rate of error as $m$ is increased ($m=2^9, 2^{10},2^{11}$).
Each individual peak shows the probability density of some actual B value being mistaken
for another B value; the larger the spread, the higher the chances of error.
The relative error for the Gaussian scales as $1/\sqrt{m}$
(the standard deviation scales slower than the mean) which is reflected in the
thinner peaks for larger $m$.
One way to numerically find a suitable value of $m$ is to use [Monte Carlo simulation](https://en.wikipedia.org/wiki/Monte_Carlo_method).
The basic idea is described in pseudocode below:
```
poisson_to_gaussian_cutoff = 15
function right_wrong(m, n_runs):
right = array(elem = 0, length = 256)
wrong = array(elem = 0, length = 256)
A = random_number_array(uniform_dist(0,1), length = n_runs)
B = []
for a in A :
if a >= poissonToGaussianCutoff / m :
B.append(256/m * random_number(gaussian_dist(mean = m*a, stdev = sqrt(m*a))))
else :
B.append(256/m * random_number(poisson_dist(mean = m*a)))
for (b,a') in zip(B, floor(256 * A)):
# array numbering begins at zero
if (0 <= b <= 255 and b == a'):
right[b] += 1
else if (0 <= b <= 255 and b != a'):
wrong[b] += 1
else if (b < 0 and a' == 0):
right[0] += 1
else if (b < 0 and a' != 0):
wrong[0] += 1
else if (b > 255 and a' == 255):
right[255] += 1
else if (b > 255 and a' != 255):
wrong[255] += 1
return (right, wrong)
M = [256, 512, 1024, ...] # candidate m values to test
N_runs = 2^20 # seems to work well
binwise_p_list = []
for m in M:
mright, mwrong = right_wrong(m, N_runs)
binwise_p_list.append(mwrong / mright) # element-wise division
```
We plot $p$ values for each bin for different choices of $m$.
[](https://i.stack.imgur.com/fXEpg.png)
For a value of $p=0.1$, $m=2^{22}$ is okay. For super-duper high quality at $p=0.01$,
$m=2^{28}$ is reasonable (although it is kind of hard to see in the graph).
## Action - Numbers
Let's stick with $p=0.1$ so $m=2^{22}$. For a smooth viewing experience, we demand
$\delta t\leq 1/60\text{ s}$ ($\geq 60\text{ fps}$). The value for $f(\lambda\_B,\epsilon\_B)$
can be found using numerical integration. I could not find a good way to fix the values of
the wavelength windows so I've set them as: $\lambda\_B = 450 \text{ nm}$,
$\lambda\_G = 530 \text{ nm}$, $\lambda\_R = 620\text{ nm}$ and
$\epsilon\_B = \epsilon\_G = \epsilon\_R = 40\text{ nm}$ (roughly based off the table in Ref 1.).
For a sun-like star ($T=5772 \text{ K}$), the values of $f$ and $\Sigma\_\Phi$ are
$$ f\_B = 0.0491401,\,f\_G = 0.0593743,\,f\_R = 0.0634818\text{ and } \Sigma\_\Phi = 9.281\times 10^{25} \text{ m}^{-2}\text{s}^{-1}.$$
Since the value of $f\_B$ is the lowest, we will use it. (We also used $f\_B$ in the preceding discussion.)
For a subject chilling at about $1.008 \text{ AU}$ and the alien sun having radius equal to $R\_\odot$, we
have the geometric factor
$$Z = \pi d\_\alpha^2/4 \left[\frac{R\_\odot^2}{1.008 \text{ AU}}\right]^2 = 1.67\times 10^{-5}d\_\alpha^2$$
where $d\_\alpha$ is (like before) the diameter of the alien subject.
We assume that the typical value of $\alpha(\lambda\_X)\sim 1$; we found out the $m$ value(s) using this.
(Otherwise, we *could* rescale $m$ somehow to account for the maximum achievable $\alpha(\lambda\_X)\ll 1$...)
We put everything together, recalling that $m$ is the *lower* limit for $\mu(\lambda\_X)$:
$$\mu(\lambda\_X) \leq \delta t\cdot Z\_T \alpha(\lambda\_X) Z f(\lambda\_X,\epsilon\_X)\Sigma\_\Phi $$
$$m \leq \delta t \frac{r^2}{4\ell^2}\cdot 1.67\times 10^{-5} d\_\alpha^2 \cdot 0.0491\cdot 9.281\times 10^{25}$$
$$ r \geq \frac{\ell}{2 d\_\alpha}\sqrt{\frac{16\cdot 2^{22}}{(1/60)\cdot 1.67\times10^{-5}\cdot 0.0491\cdot 9.281\times 10^{25}}}$$
$$ r \geq \frac{\ell}{2d\_\alpha} (7.27\times 10^{-6}\text{ m}) $$
This expression is an order of magnitude higher than the resolving-power based expression which has $\lambda\_R \sim 6\times 10^{-7} \text{ m}$
instead of $7.27\times 10^{-6}\text{ m}$.
Let us do some quick sanity checks for the numbers:
1. The total flux density incident on the subject if it were Earth-sized ($d\_\alpha = 12600 \text{ km}$) would be
$$\frac{\Sigma\_\Phi \times Z}{\pi d\_\alpha^2/4} \sim 10^{26} \cdot 1.6 \times 10^{-5} \cdot (4/\pi) \sim 2\times 10^{21} \text{ m}^{-2}\text{s}^{-1}$$
which agrees with the standard number up to order of magnitude (also present in @SandyBeach's answer).
2. Consider putting a $1\text{ cm}\times 1\text{ cm}$ plate of aluminium coated with [Vantablack](https://en.wikipedia.org/wiki/Vantablack), one of the darkest materials known, in the sun (here on Earth). The number of photons *reflected* by it in a time of $1/60 \text{ s}$ will be $10^{21} \cdot 0.01\cdot 0.01 \cdot 1/60 \cdot 0.00035 \sim 6 \times 10^{11}$. This number is still very big relative to the figure we obtained for $p=0.01$, $m = 2^{28} \sim 2.7\times 10^8$.
3. The values of $f\_X \sim 0.06$ are not too shabby given that the solar spectrum peaks at . I think that the value for red is higher than green because one has to multiply the intensity spectrum by $\lambda/hc$ to get the flux density spectrum, thereby red-shifting the peak of the distribution.
### Horror - Low accuracy, low speed attempted compromise
If we set $p = 0.6$ (for R=0,...,128, not for all R=0,...,255), we can get away with $m = 2^{17}$.
[](https://i.stack.imgur.com/ir87l.png)
We reduce the framerate to a crawling $1 \text{ fps}$. If we try to scale up $\Sigma\_\Phi$,
the planet will move further away and $Z$ will decrease in order to avoid cooking the alien.
With these new parameters, we have
$$ r \geq \frac{\ell}{2d\_\alpha} \frac{(7.27\times 10^{-6}\text{ m})}{\sqrt{2^5 60}} = \frac{\ell}{2d\_\alpha} (1.66\times 10^{-7}\text{ m}).$$
So if you try to degrade the "stream" quality by too much then you are limited by diffraction, not photon counting.
## Suspicion - Something *feels* off
1. The wavelength calculations are wrong because the light will be blue-shifted/red-shifted.
Well, the relative speed of the alien subject to its own star is much less than $c$. You are right
about the light being Doppler shifted. That just changes what kind of detector is used and does
not affect our calculations.
## Dirge - References
1. <https://en.wikipedia.org/wiki/Visible_spectrum#Spectral_colors>
[Answer]
According to [this](https://photo.stackexchange.com/a/83803/60040), you'd need a telescope, the size of "the Hubble space telescope" to read the numbers on a licence plate or recognise someones face on the distance of 10km.
So I guess, you need a telescope, the size of a planet, or even bigger to achieve what you want.
Even if you have your telescope in space, the other person is almost certainly on a planet with an atmosphere (if you want to keep track of the planet and read lips), it is almost impossible (see the link above) to see anything. Maybe you have the biggest chance trying to do this at dawn. You also want to consider weather on your chosen target planet.
Maybe an altered version of the deathstar will do the trick.
By the way such telescopes usually don't come with autofocus and people tend to move a lot.
You also have to consider, that light bends (around large objects, like stars and planets).
Having a lot of moving parts in space and a distance of 10 light years, will probably make it pretty hard to keep track of your target, because a slight wobble close to the origin light source, will have a giant influence on the other end.
As a sidenote, you might also want to consider how you treat close light sources, that will "over expose" your image.
Update
To see the same for twice the distance, you neet to double the zoom.
According to photo.stackexchange.com/questions/13717/…, you can calculate zoom from focal-length, from a given lens (in our case we take the HST specifications).
The [HST hat a focal lenght of 57.6m](https://de.wikipedia.org/wiki/Hubble-Weltraumteleskop) and can see with the mentioned resolution 10km.
For one lightyear, that would give you a focal length of 5.472 \* 10^13m. The earth has a diameter of 12'742 km.
The (mid-) Distance from Sun and Saturn is according to [this](https://de.wikipedia.org/wiki/Gr%C3%B6%C3%9Fenordnung_(L%C3%A4nge)) 1.427 \* 10^12m.
So the focal length is about thirty eight times the distance of the solar system.
To keep the f-stop of f/22 of Hubble, that would make a lens diameter of 2.487 \* 10^12m. Which is still 1.7 Times the distance from Sun to Saturn.
These Calculations, however are for lenses, [Hubble doesn’t have a lens. Like all large telescopes, Hubble uses a curved mirror to focus starlight. This mirror is located deep inside the telescope.](https://www.spacetelescope.org/about/faq/)
You might want to protect this precious piece from asteroids.
You can do the Math for 10 and 100 lightyears.
] |
[Question]
[
**Scenario**
Mining of asteroids is a successful venture in the future. However much of the resulting mineral yield is required on Earth and the problem is delivery. Carrying thousands or millions of tons of ore safely to Earth by rocket is completely uneconomic.
So, how do we do the delivery? I suggest two possible methods, but will either of them work and is there a method I haven't thought of?
**Ideas**
1. Send them from orbit to Earth as artificial meteorites that are carefully aimed at desert areas. Will the materials be recoverable and the landings safe for Earth's inhabitants?
2. Refine the minerals into metals in space and form them into solid or near-solid 'gliders' that are somewhat steerable by remote control to land in a suitable spot. Could smelting reasonably be done in space?
**Question**
Given the above ideas and information, how can I safely deliver massive quantities of minerals or metals from space to Earth?
---
**Assumptions**
1. No FTL, magic or superpowers. Just reasonable physics that could be developed in the next 200-300 or so years.
2. Propulsion methods are those that can reasonably and scientifically be anticipated in the next 200-300 years.
3. Loads can be parked in orbit before being sent to Earth.
4. I want to deliver thousands and even millions of tonnes per year - the more the better.
5. I would like to deliver large amounts of iron relative to the current world production if economically possible. In any case I want to send thousands of tonnes of gold and other metals per year.
Please ask for necessary clarifications before answering.
[Answer]
**Refine as much as possible on the asteriod**. Keep your as much of your refinering chain as close as possible to your mining operation, moving 1kg of high grade ore vs 1kg of low grade ore requires the same energy cost.
My employer makes software for optimising this process for terrestrial mines and the change in ROI you can get from subtle plant movements is quite high - extra fuel costs and uneven machinery utilisation rates can combine to destroy your profit. I'd assume this observation also applies on asteriods.
You can refine minerals in micro gravity but the processes can subtly change depending on what exactly you need. Where gravity was used to seperate two liquid substances centrifugal rotation or magnetism can be used instead.
**Use rail guns to launch packages at Earth**. Try to avoid using rockets unless you are also mining water and dry ice to make methane. Railguns can be solar powered and thus don't need fuel.
There's a big difference between mining asteroids in orbits that cross earth, and those in the deep in the belt. If your mining distant asteroids in the belt and can't guarantee that kind of accuracy with a single launch, then using a solar sail to apply course corrections while in transit may be needed.
These solar sails can be made from carbon deposits on the asteroid too, alternatively you can have these return and be reused if there exists a nice low delta-v path available.
**Make parachutes out of carbon fibre**. Technique actually explained in another answer.
**Make single-use heat shields out of refining byproducts**. Rather than get a ceramic industry going on the asteroid, or export these to the asteroid, pack the front of your payload with a sacrificial heat shield made from mining waste.
**Launch these such that they hit your own property**. Buy a big chunk of, say, Australian outback, and launch your mining products at these. Include gps trackers and radio pingers in each package. I'd suggest a window system - 12 hours a day crew can be out picking up packages, 12 hours a day packages are entering.
**The only thing you need to export to your mine is electronics and spare parts**. The parachute auto opener, the package pingers and trackers, etc. Plus spare parts for excavating.
[Answer]
Time for a bit of a frame challenge. **You've just provided a great case for an orbital elevator!**
See [here](https://en.wikipedia.org/wiki/Space_elevator) if you aren't already familiar with the concept. As I understand it the main limitation we have now that prevents this concept from becoming reality lies in the construction materials we have available. A flourishing asteroid mining industry would provide a major incentive to push humanity towards the Elevator(s), and 200-300 years of advances in material sciences should be able to overcome our current obstacles. The counterweight end could be a space station that handles and processes the incoming ore loads. This would mean that only the refined end product needs to be delivered down to Earth. With space station(s) forming a chokepoint for orbital traffic in and out of Earth, a range of secondary monetisation options like zero-g casinos, hotels, etc exist too.
Maybe you still want to play with railguns. That's fine, you can use them to launch any unwanted waste into the Sun. With two way traffic up and down the elevator(s), railgun-based planetary garbage disposal could become an industry of its own too.
[Answer]
**Steerable cargo parachutes sent to multiple landing sites**
First, as noted in the comments - *any* system that involves frequent large masses of material arriving from space and then descending to Earth has the potential to be weaponised. So, assume that there are defence systems and traffic control to mitigate any risks or there is no way to get useful amounts of material to Earth.
Second, note that this does not examine how to get the metal into Earth orbit, although re-usable solar sail "tugboats" would be my suggestion.
Smelting metals to form gliders with control surfaces that can survive re-entry - this is a non-starter. It is not possible to make a Space Shuttle out of iron, or gold, or even steel. Even if the metal was one that could be made into a glider, the amount of work required is excessive in order to create something that will be melted down and used for materials once it arrives.
Completely ballistic re-entry is also problematic - with no steering the hunks of metal will impact over a large area, partially burying themselves.
Instead, limit asteroid manufacturing to creating large swathes of carbon fibre "cloth" and lines, then make steerable parachute packs for the chunks of metal. There is no shortage of carbonaceous asteroids to get the raw materials from and the manufacturing requirements are relatively basic. A quick search on cargo parachutes indicates that a typical 'chute is less than 10% of the mass of its (non-fragile) payload. The requirement for successive drogue parachutes to slow the payload down prior to the main parachute deploying will probably bring the total mass of parachutes up to 10-15% of the total payload. If the parachute works then the metal is soft-landed where it is needed. If the parachute doesn't work... make sure that the impact area is large enough to allow for failures. The material is still recoverable, but it will need much more work.
Have at least two impact areas and switch between them on a monthly basis, so no one is loading chunks of metal at a time when more chunks of metal are coming down. Re-sell the carbon fibre parachute materials on Earth as a secondary money maker.
[Answer]
## Costs
Below some price it wouldn't be worth it. Some costs beyond normal earth production.
* Extraction and processing in space.
* Costs of packaging for drop: ablative material, parachutes, forming.
* Retrieving dropped material: if dropping in Sahara or other remote locations it will cost personnel, retrieval equipment etc.
* Costs of any property damage,
* Finders fees for people you collect a drop and refuse to hand it over without compensation.
* Control/monitoring equipment to know where it dropped/ control where it drops.
## Kinetic impactors:
Dropping mass as ablative shielded metal slugs is just scary. Mostly due to ease of weaponizing. Just a coordinate change, parachute fail, oops goes a city. It doesn't take very many tonnes to be in the nuclear weapon range. Please no. Splitting it into smaller masses, while safer, would dramatically increase the logistics costs. It expect it to take a fair bit of planning and control of drops to keep them in a sub 500Km diameter drop zone.
## Space hooks
Space hooks would be able to drop smaller batches, order tonnes, with advantage of higher lift masses. That is lifting mass from mid atmosphere to space would lower the hook orbit. Dropping mass from space down would raise the hook. A prototype space hook could be constructed and deployed within ten years. Not really a usable to solution for bulk transport of metal.
## Use the material in space
A more valuable use would be to set up construction and manufacturing in space. That would be used to build habitats like O'Neil cylinders, additional resource extraction facilities, etc. Best option in my opinion but not what you are asking about.
## Sheets/plates formed into flying snake
The risk would be mitigated if it were dropped in a low density form. Forming the metal into large sheets/thin plates is an easy to automate option. Think of a structure similar to an unrolled tracked vehicles track stretched much larger and longer. The gliding movement would be modeled after flying snake, if it works for a creature like that, it would be a good starting point.
### Basic construction idea:
Each segment something like a 2m by 20..100m by 1cm plate. The total length would be measured in Km. The segments length are varying to form wings along the track/snake body. Each plate's down side coated with ablative waste carbonic/silicate material. The uppers with some less dense material to make a st of plates act as a lifting body. The backbone would be either made of steel or more payload metal, depending on practicality. The back bone just needs to be strong enough to keep it in one piece during descent and should rotate on just one axis to keep it simple.
### Control:
The segments would need some actuators to bending between plates, and the occasional flight control surfaces. The majority could be powered by pneumatic or Seebeck effect. The head would need some energy storage to ensure operation in all stages. thus making it reasonable to assign multiple personnel to ensure its control and on target landing.
### Some costs / risks
Backbone might not be flexible enough to allow lateral steering. If the back bone is flexible enough for lateral steering it might be a source of failure. Strength of the payload metal might not be enough to support its own weight. The very long form might not be able to fit in a specific landing zone. Many moving parts are a source of failure. If tilts and things start going sideways, that might be difficult to stop. Having active control of segment dorsal movement is needed but how much is needed, how expensive I am really not sure.
## Conclusion
I don't like the meteorite approach too risky(few large) or too costly(many small). Space hooks, ladders would not be enough volume. Rockets would be not enough volume and too expensive. The flying snake would allow significant payload without too much cost per segment. It would still limit drops to the most valuable materials.
[Answer]
>
> Mining of asteroids is a successful venture in the future. However much of the resulting mineral yield is required on Earth and the problem is delivery.
>
>
>
Why would you think that? There's not much out there that we can't find right here on Earth, in greater quantities, at lower cost. The real need for mining operations in space, is to support the space ecosystem itself. Why pay to launch heavy payloads from earth, when we can find the resources we need, out there?
Showering the earth with artificial meteorites would increase heavy metals and other elements/compounds in the atmosphere, that we definitely don't want to have to breath. It would also cause a lot of additional debris to spread out in low earth orbit, eventually rendering the domain too hazardous to occupy, maybe even to hazardous to pass through.
That said, there are some rare elements, particularly the rare isotopes, deposited by the solar wind, or created by gamma ray bombardment, that you might find valuable enough, to reach out to other bodies in the solar system, and deliver them back to earth. Those will require special handling, that protects them from excessive heat and/or erosion, due to their toxicity and/or high value.
So you'll likely want to use retro rockets, parachutes or winged vehicles to deliver materials to earth. While we can build space elevators on smaller bodies like Mars and the Moon, there are no materials known to be strong enough to build one for Earth. Luckily, the Earths atmosphere provides a free breaking system, so you don't need the elevator here, for that. Getting material onto the moon is a different story. No atmosphere, so an elevator makes a lot of sense for bringing things down, but you can easily use rail guns to move material off of it.
We're never going to build massive space stations and ships, or large colonies on the Moon or Mars, by launching stuff/people on rockets from earth, because doing so will destroy our atmosphere, particularly the ozone layer. Achieving a sizeable and sustainable population of humans in space and on other large bodies, is going to require gigatons of material. That's the primary reason why you have to do large scale space mining. It dramatically reduces the cost of building things in space, as well as the reduction in harms that a massive space industry could cause here at home.
---
All that said, you could mine organics from asteroids/comets and use those to make giant helium balloons, and other things. Mine Helium 3, oxygen and hydrogen (for fuel) from the surface of the moon, containerize it, then launch it into a receiving orbit around the earth. Use some of the helium to fill the big balloons, attach an appropriate amount of cargo/passengers and fuel (needed for descent thrusters), then slow it down just enough send it slowly descending into the atmosphere. Rather than a big fiery re-entry, you have a relatively low temperature, safe descent into the gravity well. You'll have to pump a bunch of that Helium from the floatation bag back into a cargo tank to get all the way to the ground.
The helium 3 has potential energy uses here on earth, the oxygen and hydrogen can be used for any powered re-entry vehicles and radiation shielding. The metals are needed in space for structural components, and many of the other materials can be used to make ceramics for all sorts of purposes.
---
I would add that gold is worth at least 5 times as much in orbit around the Earth or Sun, as it could ever be worth on Earth. I am not sure gold exists in high enough concentrations, in any of the asteroids, to even be worth the cost of extraction. Unlike the earth, where plate tectonics, geothermal energy and microbes have played a major role in concentrating quantities of the stuff, here on Earth. You don't get that so much on the asteroids.
---
The distance from the mine to the refinery isn't as large of a cost factor in space, as it is on Earth, where you can't simply coast most of the way. Provided you are not in too big of a hurry, you can use low delta-v orbital changes, to send feed stock to the refinery, and most of that can be provided by free solar energy. So the harvesters work the asteroid belt and send payloads to an orbit between there and the Earth, where the refinery process a continuous stream of material, containing all the elements, in roughly their solar abundance ratios. Energy for refining isn't a concern, but industrial quantities of the chemicals used in the refining process will be hard to come by.
[Answer]
Effective asteroid mining is going to act a lot like an industrial revolution. You'll have feedback loops on feedback loops.
I can talk about various phases. The first problem is making it cheap enough to send a significant amount of material to the asteroids. Currently it costs 10k$/lbs to reach orbit. Then another pile of wealth to reach the asteroids.
Basically, everything in orbit costs as much as pure gold. Including reaction mass.
I mean, imagine a gold mine, where it was literally a pile of gold on the ground. Except every pound of material you brought to the mine cost you a pound of gold. The food, the workers, the railroads, the dynamite, the picks, the carts, the roads, the houses for the people.
Making that economical is going to be very difficult.
Making an effective asteroid mining system when this is true isn't going to be effective. You need an industrial base that is **cheaper** than 10k$/lbs away to pull this off.
There are a number of ways you can do this. The naive solution is just to make space launch cheaper -- beanstalks, fountains, hooks, linear accelerators.
All of these work better in a low gravity sink. So one plausible case is that your civilization has set up an industrial base on Mars or the Moon. From there, getting to space is going to be orders of magnitude cheaper, and setting up one of those technologies to make it even cheaper is going to be cheaper as well.
An industrial base on the Moon or Mars that reduces the marginal cost of matter in orbit down to 100$/lbs can then be used to build a real asteroid mining industry. The first consumer of the resources won't be Earth, but rather the Moon or Mars, where materials already cost more than Earth and deliver is also cheaper.
This results in a feedback loop as the asteroid materials make resources cheaper on the off-planet industrial base, which in turn makes asteroid mining easier to do.
Once you have this, you start building stuff like a skyhook in orbit around Earth. It trades momentum from incoming mined packages for momentum from planetary launches. The marginal cost of leaving the Earth drops to say 100$/lbs (the energy required to reach the bottom of the skyhook), and for every pound of mass you lift out of the gravity well you get to lower 1 pound of any metal you choose from orbit.
This makes the skyhook's operational profit huge, which means that even if expensive you can build a lot of them. This will continue until the price of almost every raw material on Earth drops below 100$/lbs and building new skyhooks is no longer worth it.
While it might be viable for a short term period, actually dropping an iron-wrapped gold core asteroid from orbit and picking it up after it impacts is not going to scale very well. The chaos of reentry means that you might lose the gold, and the heat:payload ratio won't let you do this on a planetary changing scale without boiling the atmosphere.
As you near a K-scale 1 civilization, your problem becomes not boiling the planet, as the energy your civilization uses starts approaching the ability for the planet to emit heat. The reentry of large numbers of asteroids is a lot of waste heat.
---
So I see a bunch of phases.
Phase 1 is industrialization of Luna/Mars. Earth is heat-trapped as a sub-K-1 scale civilization.
Phase 2 is Asteroids materials mined and used to further Luna/Mars industrialization, including Beanstalks and Skyhooks and the like. But not around Earth.
Phase 3 is where you start seeing seroius lift infrastructure deploying that over Earth. Every pound of matter you launch, you get a pound of asteroid mining materials. Price of any raw material on Earth falls to 100$/lbs.
Phase 4 is when the off-planet infrastructure cuts itself loose from Earth, which becomes a relativly impoverished backwater. Civilization breaks the K-scale 1 barrier, and becomes interplanetary. Most humans still live on Earth, it requires a civilization closer to K-2 scale to manage a planetary exodus.
[Answer]
**Its probably best not to send the minerals back to earth**
In your world it appears that there is industry in space. That industry and the space economy as a whole will need space ships, tools, and possibly space stations and other space infrastructure. All of those things are made of metal, and metal is heavy. It costs a lot of money to move heavy objects from the earth into orbit. At present it costs several thousand dollars per pound. In some cases, like 100X the cost of the metal itself.
You can make a huge profit if you are able to manufacture large components in space, or on the moon and then deliver them to their final destination in space without having to launch from the earth.
[Answer]
Let's take look at what lands on a regular basis as of today or in the past, on this planet
* space dust
* meteorites, including big ones
* Space shuttle
* Soyuz landing capsule, different sample return missions
* Falcon 9 first stage
* Starship test model - almost, and it made out of **steel**
+ and it quite a good model for a glider, how it may look like, and it can RUD itself without that much of dust, on some water surface
if we throw out big asteroids which had lithobraking at the surface of our planet in the past, leaving km's wide craters, then Space shuttle or Buran(those few times it flew) - are the biggest, by a mass, objects which performed not only a landing but soft landing. [Space Shuttle orbiter](https://en.wikipedia.org/wiki/Space_Shuttle_orbiter) dry mass was 78 tons, and 14 tons of payload for the return mission. Not sure if one is included in another, but anyway let's round it up to a 100t.
out of that 100 t for a decent, u probably do not need those ascent engines and fuel systems for them and if we look through all the system it has for humans they can be thrown away as well, and if we lower the safety margin which required for humans we may get to some space shuttle-like construction which is capable of soft-land return a payload of 50t. Then for rare elements, it is a lot - u need just 100 landings a year to totally smash the market under your control.
## That pesky iron, can't hold it anymore
as mentioned in comments by AlexP - *The annual production of steel is about 1,900,000,000 tonnes.* - I won't even bother to look it up to check, as I know - yes it is thousands of millions of tons.
Maybe to move the market you may need 10% of that, if u manage to get it, you can be a steel baron, but it still a lot of mass.
Landing as ore is not necessarily useful, as ore is relatively cheap compared to the end product - steel, do not remember the exact number but it is in the range of 20-40% of the price of the end product - steel. A lot of energy is used in reducing oxidation to metal.
However, there becomes to be important what for do u need iron or iron oxides.
There is such thing as [Iron fertilization](https://en.wikipedia.org/wiki/Iron_fertilization)
>
> **Role of iron**
> About 70% of the world's surface is covered in oceans. The part of these where light can penetrate is inhabited by algae (and other marine life). In some oceans, algae growth and reproduction is limited by the amount of iron. Iron is a vital micronutrient for phytoplankton growth and photosynthesis that has historically been delivered to the pelagic sea by dust storms from arid lands. This Aeolian dust contains 3–5% iron and its deposition has fallen nearly 25% in recent decades.
>
>
>
>
> A full-scale plankton restoration program could regenerate approximately 3–5 billion tons of sequestration capacity worth €50-100 billion in carbon offset value. **However, a 2013 study indicates the cost versus benefits of iron fertilization puts it behind carbon capture and storage and carbon taxes.**
>
>
>
Iron fertilization by sea or aerial vehicles may be expensive, but a shower of iron oxide particles from space - may be a way to go.
>
> The Redfield ratio describes the relative atomic concentrations of critical nutrients in plankton biomass and is conventionally written "106 C: 16 N: 1 P." This expresses the fact that one atom of phosphorus and 16 of nitrogen are required to "fix" 106 carbon atoms (or 106 molecules of CO
> 2). Research expanded this constant to "106 C: 16 N: 1 P: .001 Fe" signifying that in iron deficient conditions each atom of iron can fix 106,000 atoms of carbon,[45] or on a mass basis, **each kilogram of iron can fix 83,000 kg of carbon** dioxide. The 2004 EIFEX experiment reported a carbon dioxide to iron export ratio of nearly 3000 to 1. The atomic ratio would be approximately: "3000 C: 58,000 N: 3,600 P: 1 Fe".
>
>
>
### combining numbers, pretty much in an arbitrary way, out of curiosity
>
> A full-scale plankton restoration program could regenerate approximately **3–5 billion tons** of sequestration capacity worth **€50-100 billion** in carbon offset value.
>
>
>
>
> Antarctic circumpolar current into organic carbon, the resulting carbon dioxide deficit could be compensated by uptake from the atmosphere amounting to about 0.8 to **1.4 gigatonnes of carbon per year**.[67] This quantity is comparable in magnitude to annual **anthropogenic fossil fuels combustion** of approximately **6 gigatonnes**.
>
>
>
>
> ... **each kilogram of iron can fix 83,000 kg of carbon** ...
>
>
>
to fix 6 gigatonnes we need about 72 million tons of iron, delivered over a large area, landing as 0.5-1um particles, preferably. So there may be a business of a lot of iron to be landed at almost anywhere of that 70% of the surface of the planet. And deliver it out from space totally worth it. And we talk about **trillions of money** per year buried in there as a service.
* you may need phosphorus as well, not necessarily in similar quantities, as it may be a more soluble thing and moves easier in and out.
## what iron looks like as a soft landing
* let's say we did it - 100% iron space shuttle, it fertilizes by ablation oceans at descend, and soft lands 100t
* another thing to mention that suttle does not need any energy stored in it as it gets it constantly at the descent.
So 2 billion tons of iron annually in 100t packages will look like 1 shuttle per 1.57 seconds.
if we keep some reasonable time between them for one land strip, let's say 5 minutes, then we need 190 landing strips for them. And if we aim as more or less the same region then it is constant plasma channel, wzu wzu wzu, every 1.5 seconds, the constant roar of hell fire.
But not impossible something like a 50x5 km piece of land, or sea can suffice.
## Gliders, feasibility
I would say it quite feasible, and maybe even preferable. if one builds them in orbit, gives them a small kick for deorbiting, then when it lands - it is a pile of materials which proportions are exactly, or very close to, the which one needs to build a space shuttle, space capable vehicle, or in more general aerial or other technology advanced vehicles - like cars as an example. And that 50t payload can offset the average composition to any industrial useful mix, to any specific or general proportions of materials and metals and elements we use or may need.
if not the whole construction, some parts of it are ready to be reused in other constructions. Build it in a way to increase the reuse of parts - it may be an important factor here.
or it can be used as a whole - retrofit engines in it and go in orbit.
* For to build that relatively advanced glider, it needs to have developed industry in space, in orbit. And then just iron delivery may not look that sweet if u manage to build processors in space - one 50t delivery may be worth 0.5B in retail money.
* if you imagine crowded earth striving for resources, considering 300-year time frame, and all iron ore pits are long gone - then again energy from space can be more useful than iron delivery - as if u take random rock it has a meaningful percentage of iron or aluminum in it - it just requires more energy to extract and refine it, a few times more than from better iron oxide ore. And if you deliver the energy you will solve that iron aluminum crysis.
* there can be more primitive ways to make the delivery, requiring less technological capabilities for those return payloads, some are smart, some are funny, some are not - but given 300 years time frame for technologies and the whole space mining business existing there, I won't consider making such delivery glider to be a problem at all. As long as it does not use what u can't easily find and mine it is okay. And in asteroids, u can mine everything we have on the planet, not necessarily in one place but ...
* using water as a source of hydrogen for fuel, can be a waste, but using hydrogen from Jupiter for the same purpose maybe not. But generally, I mean an absence of fuel in the whole operation from asteroid to the planet's surface, as it can be done that way easily, with technology and energy available in space.
* iron and aluminum are not the most interesting bulk metals, there are others that are bulk metals as well for stainless steel or bronze copper - Cr, V, Co, W, Ni, Cu, Zn, etc.
## Conclusion
we can see that precious metals delivery maybe not a problem, and surprisingly even iron delivery may be quite feasible, as well on the scale of our current world production.
put enough effort in bringing up technologies required for glider productions, like the space shuttle hull type, which development and research how to build one in space you can propel by precious metals, if there is no other incentives at work and Soyuz like capsules or their smaller counterparts delivering rare metals to fuel that monetary train - this type scales well enough, up to tons, and are simple to buid.
processing can be done in space or in orbit - does not matter that much, and depends on all sorts of premises. But fission rockets, solar sails, fusion propulsion it all within the defined time frame and those can be efficient enough to not worry about do you move a whole asteroid or just a refined part of it.
I would suggest making a stream of delivery of hydrogen from Jupiter, do bind oxygen in easy to hold form, which is a waste product from making metals, but it is not a necessity as keeping it in liquid form also isn't that difficult. But when you reach some gigaton a year month day hour - it may make sense at some point.
* do not think about that problem as keeping fuel in a rocket, we talk about billion tons of it per year. it requires setup, but there is nothing special about it.
* venting it would be a waste, even if we have sources of it, but still, the element conservation paradigm better to get used to it from the start, no one knows where a day comes and u would need to sell it to mars guys or space habitat folks.
However, delivering bulk metals is not the best way to address the resource shortage of mines. energy for recycling, energy to get it from the sources which are not considered as ore - is more preferable way. The energy dissipated by de-orbiting in the atmosphere may be manifolds more than the extraction of these metals from poor ores. So heat pollution wise it is better to deliver energy, than bulk metals.
Drop shoot delivery scales well, from small quantities to quite big ones, but at some point, it makes more sense to invest in orbital rings, and alike, they are technologically feasible even at our today's technologies - incentives, and materials in orbit are our current problems. But when we talk about trillions of direct and indirect profits and billions of tons of materials in orbit - then it makes sense to make those. So you may start the business small, but later on, u can have resources to develop and build more efficient means.
## some additional notes
For rare elements, which are at ppm ppb concentration in a typical space ore - u need to extract them in space - because it is easier and energy is more available there and more easily accured. At the same time, you can process bulk material separation. A refinery in space will be quite a construction to see. So after u mine your first 10% gold/platinum content asteroid - invest in making the refinery. And then moon regolith will be the source of most materials u need - for earth it is the best source of most elements.
energy take from solar - it worth almost nothing with basic automation.
[Answer]
I will join the crowd in worrying about weaponizing the delivery system. Think of [i]The Moon is a Harsh Mistress[/i].
However, if we ignore that there's another delivery system that is much simpler and less prone to failure:
You need to do your processing in a very low gravity environment, I don't know just how low you need: Form your refined metal into foam--this is impossible on Earth but quite possible in microgravity. The objective is to give it a density less than 1 gm/cm^3.
Once you have a delivery package ready you use your refinery slag, make more foam to serve as a heat shield. Load it into your mass driver and fire at a piece of ocean reserved for the purpose (anyone who ventures into the area had better have up to date tracking of incoming objects so they can dodge if need be!) If your gunnery is good enough you don't need anything but metal and shield--there is no braking system other than the heat shield, the packages hit at terminal velocity.
The thing is, since they are lighter than water they float even if they break on landing.
You scoop them up, for most purposes you are going to have to melt them and recast into whatever shape you need. There will be some ability to use them directly, though--pound for pound metal foam is stronger than the base metal and if you have big enough pieces you can build ships that can't sink. (They build some "unsinkable" boats now but it's done with adding foam rather than the hull itself being the flotation device--the current versions can still sink if they take enough damage.)
[Answer]
**Won't anyody think of the velocities? Hit the moon!**
Moving much of the refinery chain close to the asteroids is tricky, as the machinery is heavy and probably requires much maintenence - meaning more people, more life support in the belt. Same goes for manufacturing. Still some refining will happen in the belt, as will some manufacturing, the economy is different though than on earth because maintaining fragile machinery and more fragile humans in space is difficult, expensive and dangerous before they even started to work.
for the early phase of asteroid mining, I propose mass drivers with two twists:
* the target aquisition software is controlled by states, not private enterprises. Mining corp says to NASA "we want to launch 5t plusminus 50 kg on time x at target y", NASA confirms its safe, computes a firing solution, at time x the gun confirms that indeed 5t are loaded and fires. Only "responsible" states are allowed to control mass drivers, same as with nukes (Apartheid era South Africa had nukes. Hmm.)
* Everyone shoots at the moon and only at one half - probably the western half (the one visible when the moon is moving away from you). All landing times fall into week long landing timeslots, inbetween the landing slots there's time for ore retrieval (onto the safe side of the moon, from where processing and launching to earth happen). Mining cooperations have designated areas for which to aim as landing spots.
How fast will the cargo land?
This part is tentative, I need to check my thinking here:
Relative to the Sun, escape velocity near the earth is 42.1 km/s, near Ceres (as a body in the asteroid belt) 25.3 - so unless I'm mistaken everything arrives at earth orbits with about 17 km/s (needs accoutning for earth's orbital speed)
Moons escape velocity is 2.38 km/s, earths escape velocity at the moons orbit is 1.4 km/s, so roundabout 3.8 km/s + 17 km/s (needs accounting for moons orbit around earth(which is why we want to land on the west side, not the east side:))). However that's far better than entering earths atmosphere with 11.7 km/s + 17 km/s.
I don't think aerobreaking is feasible, I think lithobreaking with less speed is better and the chance of hitting a city on the moon is lower too. Because there are no cities on the moon.
] |
[Question]
[
I've been reading about stellar engines. [The Wikipedia article on them](https://en.wikipedia.org/wiki/Stellar_engine) says this about the acceleration they could provide to a star:
>
> Such thrust and acceleration would be very slight, but such a system could be stable for millennia. Any planetary system attached to the star would be 'dragged' along by its parent star.
>
>
>
I'm writing a sci-fi novel about Earth going rogue. I would like to know if, **by the same principles, if the Earth gets accelerated prograde out of the solar system, would the Moon be dragged along?** I imagine so since the Earth is two orders of magnitude more massive, being the dominant mass in the Earth-Moon system.
Further details:
* The Earth is accelerated by a mysterious force, giving it a push of ~0.025 g for twelve hours;
* The force acts only on Earth and has a gravity gradient of 0.0001% (less tidal effect than the Sun).
I imagine a set of possibilities:
* Small or negligible effect on the Moon's orbit;
* Very strong effect on the Moon's orbit, changing it into a much more eccentric shape;
* The Moon escapes the Earth-Moon system on a tangent - tides get weaker and weaker as she leaves;
* The Moon does a very close flyby, leading to one devastating extinction event with earthquakes, tsunamis and volcanic eruptions of biblical proportions - then she escapes the Earth-Moon system;
* The Moon's orbit becomes very eccentric with a very low periapsis - same as above but on infinite repeat;
* Collision. That would be a very short and anticlimatic story;
* ???
I don't have the math or the physics in me to figure what would most probably and realistically happen, so I'm coming here for help because you guys always make my day :)
[Answer]
**Farewell Luna. But, there might be a way...**
I simulated the Sun-Earth-Moon system to determine the trajectories of Earth and moon. With your given acceleration $a=0.025g$ and $T\_{accel}=12\ \text{hours}$, the **Earth categorically, and quickly, leaves the moon behind**. One parameter we have to play with is the angle of the relative position of the moon, $\phi$, at the time when acceleration begins. It is simplest to see in a diagram.
[](https://i.stack.imgur.com/BMlTD.jpg)
Earth is orbiting CCW around the sun, and the moon is orbiting CCW around the Earth. If $\phi=0$, then the Earth and moon are moving in the same direction when acceleration begins. If $\phi=\pi$, then the Earth and the moon are moving in opposite directions when acceleration begins. Here is an example trajectory with $\phi=0$, over five years. It's in the reference frame of the sun, which is at the origin of axes:
[](https://i.stack.imgur.com/YvRcN.jpg)
We see the moon continues to orbit the sun, and is very much left behind. It is interesting to look at the Earth-Moon distance over time. Here is a plot with $\phi=0$:
[](https://i.stack.imgur.com/sa6eO.jpg)
For $0 \leq \phi < 2\pi$, I overlaid the Earth-moon distance plots. Each thin line on the plot below is a distance time graph for a particular $\phi$.
[](https://i.stack.imgur.com/VY2Ip.jpg)
We see that most trajectories (dark lines) have the Earth-moon distance increasing forever. A few lead to close encounters or impacts. After a close encounter, the moon is still lost. The range of $\phi=\frac{\pi}{40}(10 \pm 1)$ lead to approaches below the fluid Roche limit of the moon. Impact/ closest approach happens about 16 hours after the start of acceleration.
From this plot we learn: *Independently of the initial configuration ($\phi$), the Earth either leaves the moon behind, or collides with the moon.*
**...to save her**
Maybe you *want* to keep the moon around? The acceleration would need to be drastically reduced. In order to put the Earth on a hyperbolic trajectory, it will also need to be applied for much longer. Here are 4 trajectories overlaid ($\phi=0,\ \pi/2, \ \pi , \ 3\pi/2$), with $a=0.025g/600$ and $T\_{\text{accel}}=500 \ days$.
[](https://i.stack.imgur.com/oqpl4.jpg)
For the trajectory with $\phi \sim 3\pi/2$, here is the Earth-moon distance time graph:
[](https://i.stack.imgur.com/rKHur.jpg)
Other values of $\phi$ still lead to the moon being lost. When the moon is retained, the lunar period is reduced to about 20 days, and the lunar orbit is highly eccentric. At perigee, the moon would appear *huge*, with an angular diameter of about $5^{\circ}$; ten times what we are used to!
From this we learn: *the forces and timescales in the question are two or three orders of magnitude away from that required to retain the moon, and even then, the start of the acceleration needs to be at a (somewhat) specific time.*
[Answer]
You're going to lose the Moon.
At the Moon's current distance, the Earth's gravity can only change its velocity by $0.002m/s^2$
The mentioned acceleration of about $0.25m/s^2$ dwarfs that, and if at any time during this acceleration, the Moon's relative velocity to Earth exceeds Earth escape velocity for its distance, Earth loses it. At a distance of 384,000 km, Earth Escape velocity is about $1.44 km/s$.
Earth can't drag the Moon hard enough to catch up, and you're planning to put more than 10km/s on the Earth. It's gone.
[Answer]
**Goodbye, moon!**
The moon's centripetal acceleration is always pointed at the earth, and has a value of just 0.0027 m/s^2. If you accelerate the earth in the opposite direction at 0.025g (0.245 m/s^2), the earth will move away from the moon with a net acceleration of 0.242 m/s^2. As the earth moves further away, the force of gravity lessens, resulting in a larger net acceleration, only ever increasing the distance between the earth and the moon. The earth's pull on the moon is not strong enough to overcome the push you're imparting on the earth itself.
This covers the simplest situation of accelerating directly away from the moon. One could also change the direction and timing of acceleration to generate a collision between the earth and the moon, or a close flyby. I suspect you could do some interesting things to slingshot the moon in certain ways, but I don't think it'll be possible to keep the moon in a stable orbit throughout the earth's acceleration.
[Answer]
**Depends on direction of thrust and relative position of bodies**
Firstly, the Earth-Moon system will definitely be disturbed. The most likely scenario is ejection of the moon, though collision is possible if you happen to... well, accelerate the Earth into the Moon.
You are applying the force to Earth only, which means that you are disturbing the parent-satelite system by adding an external force to **one** of the bodies only. If you wanted to keep the Moon in current orbit, you'd need to accelerate the system as a whole. Otherwise you are changing the relative velocity of the two bodies. As a simplification that might be easier to imagine - accelerating the Earth by X km/s in a particular direction should effectively be the same as accelerating the Moon by x km/s in the opposite direction - what matters is the relative change in velocity.
As you're accelerating the Earth (by your calculations) to **42km/s** that means about **12km/s** increase in speed over 12 hours. With a Moon orbital velocity of about 1km/s that change means that Moon's velocity with regards to Earth is anywhere from **13km/s** (well over Earth escape velocity) to **11km/s** retrograde (Moon's orbit is reversed). EDIT: Correction regarding escape velocities. At the escape velocity of the Moon from its current orbit would be about √2\*current orbital velocity. Which will be about 1.44km/s. Hence, the Moon will be ejected.
And of course accelerating directly into the Moon (which will move about 1/60th of its original orbit over the course of Earth's acceleration) will also lead to a collision.
[Answer]
Probably not with your criteria that the force only affects the Earth, for 12 hours, and at 0.025g. Others have explained well why that wouldn't work. We'd leave a lot of satellites behind as well. If the force affected the Earth/moon system, then sure.
If the force only affected the Earth, it would have to be controlled to keep the moon with it. If you have a force capable of accelerating the Earth at 0.025g, you could move it into a position so that the moon is heading straight for it and in the direction you want to go. Start accelerating away so that it isn't close enough to ruin the Earth. If the moon were only 1/3 as far as it is today, you could accelerate Earth at 0.0245g away from the moon, and the moon would be accelerating towards the earth at the same rate. The tidal forces of the Moon on the Earth would be 9 times as strong.
Of course when the acceleration of the Earth stopped, you'd need to do some maneuvering to get the moon back into a stable orbit to keep them moving through space in a happy little system.
[Answer]
There should be a way to do it without losing the Moon, but there would be a very narrow range of timing. If the acceleration is started just right before the Moon is in the part of its orbit away from the sun, the Earth would come towards the Moon. If it just passes the Moon, the distance could be small enough that the gravitational attraction comes close to matching the acceleration.
[Answer]
You can do a rough calculation for the general case by calculating the Moon's kinetic energy with the Earth at rest, and let that be P. The Moon gravitational potential energy in respect to the Earth can also be calculated and let that be U. From the virial theorem stability yields 2P + U = 0 (approx).
You can approximate by ignoring the drag effect of the Earth on the Moon during the Earth acceleration phase (this could be roughly estimated however), and at the end of the acceleration you can get the new Earth-Moon distance and the new Earth speed. That allows you to calculate the new values of P' and U'.
Or you can also apply the equations to calculate the [characteristic energy of the Moon](https://en.wikipedia.org/wiki/Characteristic_energy) after the acceleration, assuming neither distance nor position change during the acceleration (i.e. the Earth is teleported at the acceleration-ending point with the final velocity in zero time).
In both cases you'll find the same result - the Moon is lost.
(This of course assuming the Earth doesn't collide with the Moon)
[Answer]
Answer: No, we loose the moon and all satellites too.
Consider that your moving of the planet will also cause all LEO satellites to enter the atmosphere and burn up in first few hours. ISS is dead too, unless the astronauts take the life-raft down to earth in the first few hours.
The only satellites to survive physically would be in Geostationary or high graveyard orbits, and I suspect they'll be left behind as well, eventually to orbit the sun or maybe the moon in a very wide circle, which itself will have a vector approximately parallel to the solar plane, but its direction depends where the moon was in its orbit as the earth left.
In a perfect world, the moon would end up in orbit of the sun, but its much more likely to be going out or toward the sun.
[Answer]
I think that the answer is that the moons orbit would be changed into a more eccentric orbit, since the gravity of earth will poon on the moon and she will come on our way, but the centrifugal force will make it stay in orbit, although maybe more eliptic. This, of course, is only if the earth were to speed away slowly.
If it were to go away faster, the moon would stay behind.
] |
[Question]
[
Someone has the power to turn themselves invisible, as well as other objects in a short radius, by bending the light around them and the invisibility can last as the person wants through conscious effort. There are no limits as to what or who the person can turn invisible so long as they are only partially within their radius, so if the base of say, an apartment just enters the edge of their radius, they can turn the entire building invisible. They can also pick and choose what is invisible or visible, such as making a car completely invisible but not the person driving it.
What would be the required secondary powers this person would need for their powers to function as described, and how could they use their powers in creative ways that some people wouldn't expect?
[Answer]
# Somehow perceive the world while blind
Your eyes detect light by absorbing it in ways that generate detectable signals your visual cortex then assembles into your view of the world. Being invisible means not absorbing ambient light, or interfering with it in any detectable way. So while invisible, your person is blind. If they're not blind, they're not really invisible. They're going to need a way to deal with this.
# Maybe Communication Powers
Likewise, being invisible also involves going completely radio silent. No wireless communication, no talking over the radio, etc. If the invisibility doesn't extend to ALL electromagnetic radiation, anyone who cares will probably find it fairly trivial to build a detector to triangulate the position of invisible folks (especially if they're carrying active transmitters).
# You probably want some limits on partial invisibility
If you step back a few parsecs or so, for a more galactic point of view, "the earth" as a whole is a single object. Part of it is clearly within the effective radius of this individual's powers. Consequently as you've described it, this person could turn *the entire Earth* invisible.
[Answer]
Aside from just bending the light around a subject, bending light along other paths is also useful.
**1) Bend light from one place to another to cover over something.** This is sort of like the clone stamp in photo-shop or paint.net.
Example: An invisible person standing in the grass, dirt, or water displaces the surface with a dent in the shape of their footprint. To correct defects in the illusion one might bend light from a nearby patch of ground to cover over the part of the image where the feet were.
**2) Bend light to make something look like its in a different location.**
Example: Someone is in a fight with you. You bend the light a little to the left, so everything looks shifted over. Now every time they aim at you they miss badly.
Example: You are afraid of snipers. You routinely bend your image so that an ordinary person could never get a good shot.
This is accomplished by bending the light in a vortex or swirl pattern. In the figure below you are at A. Light images W, X, Y, Z come out from A at different angles. You bend them all slightly clockwise. Now observers O1, O2, O3, O4 (instead of seeing your true image at A) see images I1, I2, I3, I4 instead. To each observer you will appear to be in a slightly different position, but none of them will see your true position.
[](https://i.stack.imgur.com/BFz5x.png)
Of course since you are smoothly swirling the light you are really generating an infinite number of illusions, each at slightly different angles. The great thing about this trick is you don't have to know where the observer is for it to work, and it works for infinitely many observers. Each trick has its weaknesses and the catch with this one is that someone directly overhead would still see where you were (although you may appear rotated).
**3) Bend only some of the light. Now you have two images.**
Example: You are walking down the street alone. You bend the image of yourself partly so that from certain vantage points it looks like there is two people.
The figure below shows how this is done. You are at A. Light images X and Y are exiting you from different angles. Ordinarily observer B sees image X but does not see Y because it is going off a different way. You take the light going through cross section P and bend it so that it is directed at B. Now B sees Y and it looks like there is a copy of you at C.
Of course one limitation is that you must know where B is in order to direct the duplicate image at them. Also an observer at D will just see you as a black hole since you stole their image of you. To avoid this, just take light from an angle that misses all the observers.
[](https://i.stack.imgur.com/1jK7h.png)
Of course you can extend this to make even more images of yourself (or anything else for that matter). In the figure below, you are at A. Light images V, W, X, Y, Z exit you from different angles. Normally observer B only sees image X. You take images V, W, Y, and Z and bend them towards B. Now B sees copies of you at A1, A2, A3, A4. When they look around, it now looks like there are five of you. Note that each copy looks a little different because its from a slightly different angle.
[](https://i.stack.imgur.com/ETX9Z.png)
**4) Bend light to make something look different.**
Example: You want to look taller, so why not.
[Answer]
'Realistic'-wise this might require some rethinking.
Take the example of the person driving a car. The talent can decide whether the car is invisible, the person inside it...what about their clothes? Do they have to specify for every single object in the car, and what counts as an object (is a bottle of water one object, or does it comprise bottle, bottle top, and water)? Do they have to specific for every single molecule, or every atom...?
The atmosphere is touching them, can they make it invisible? What about objects in the atmosphere like clouds, birds or planes? Or objects within or on the Earth, which is within their radius...?
This level of control with require a kind of super-awareness and super-computation power far in excess of any human brain. This will be far more significant than mere invisibility.
In practice, as others have suggested, some kind of mind-altering power so the talent is not noticed is likely to make far more sense than selectively moving individual photons.
[Answer]
# A Somebody Else's Problem Field.
Being invisible is definitely really cool. You can go do anything you want, whenever you want, without anybody being able to mess with you. [At least as long as you don't have invisible eyelids, that is; then you become your own problem.](https://en.wikipedia.org/wiki/The_Invisible_Man)
However, invisibility does have one problem: no matter how good it is, [the Observer Effect](https://en.wikipedia.org/wiki/Observer_effect_(physics)) dictates that an invisible person will have *some* effect on the world around them. This generally takes the form of foot-shaped depressions in the grass, or unexplained bumps in the night. Utilized by such greats as Slartibartfast, The Doctor, and the Campaign for Real Time, **a [S.E.P. Field / Perception Filter](https://tvtropes.org/pmwiki/pmwiki.php/Main/PerceptionFilter) causes people to ignore these telltales, making you completely invisible.** At least until somebody starts [jumping up and down while also blinking really fast.](https://tvtropes.org/pmwiki/pmwiki.php/Literature/LifeTheUniverseAndEverything)
[Answer]
Realistically speaking, the ability to influence the trajectory of individual photons would not yield the kind of results you are wanting, at least not consistently.
Even worse, the exercise of trying to marry a power like this to reality is, practically speaking, almost impossible.
Bending light around an object so that it was invisible would mean that the powered individual would need to be omniscient, at least specifically with regards to where each observer of the space being manipulated is. The view angle of the observer at each moment that each photon were to enter their retina and then be processed by the brain. This would need to happen for every photon that were to come in contact with the surface of the object, and for every photon that should enter the visual cortex of observers, and what to do with the excess photons? Honestly the issue, while mathematically MIGHT be possible (I only throw this maybe in there because the mathematics of accomplishing this are FAR beyond myself), is so incredibly complicated that it is better off sticking to the "because magic" route if bending light is set in stone as the basis of his powers.
Something like being able to alter the mass of an object so that light simply doesn't interact with it is a little bit closer to what you describe, but even this introduces a whole heap of problems if realism is a sticking point (ie. a massless car disassembles at a molecular level. And even if the forces that hold it together are not effected somehow by its loss of mass, it certainly wouldn't be able to still interact with other physical forces like gravity, and the driver's interaction with those forces).
[Answer]
**Light manipulation and some level of mind control.**
Initially, the ability to bend light seemed enough. Just with that, you'd already be able to turn yourself and anything else invisible, potentially create a heat beam (concentrate a lot of infrared light on a single point), see better in the dark (force light to keep going back into your eyeballs, thus causing the necessary stimuli to see) and the ability to get a perfect tan. The main problem here was your car example. For light to hit the driver, thus making him visible, while keeping the car invisible, it'd need to go through the car as if it didn't exist, which simply isn't really possible (for the visible light, that is).
However, it could happen, if instead of just light manipulation, your character also had the power to control minds, blocking the information sent by the eyes and plant images on people's heads. That way, you'd be able to make anything invisible simply by making people unable to perceive what you don't want them to. It would also mean you can create illusions, especially if you're also able to induce fake stimuli from other senses, even to the point of making someone believe they're cooking up in a place below 32 Fahrenheit/ 0 celsius. This however would mean that, without light manipulation, you'd be able to avoid detection by guards, but not by the cameras (reminder that if light doesn't hit your eyes, you'll be essentially blind, unless you just deflect the light that reaches the cameras).
[Answer]
### Frickin' lasers!
(Sharks not included.)
You need a light source. With selective bending of light, your range sets the radius in which you can capture all the sunlight available, focussing it into a collimated source.
If you can block light, you may also be able to intensify light. This will give you an [optical amplifier](https://en.wikipedia.org/wiki/Optical_amplifier). Even without that though, you could carry this around with you.
Finally, if you can bend light such that it loops back round on itself again, you have created an [optical cavity](https://en.wikipedia.org/wiki/Optical_cavity). Combine this with your optical amplifier, and that gives you all the major ingredients of a laser.
And finally of course you provide the targetting mechanism to place the laser dot on whatever you want to heat up.
I should mention of course that when you're playing with large amounts of energy like this, you would want to be *really* sure you've got it under control, otherwise you could get a bit more than just sunburn. I would strongly recommend including some kind of shield to deflect all light coming towards you from the laser's location, just in case.
[Answer]
# Useful side powers
* Something that allowed them to stay aware of their surroundings. Sonar? Perhaps they can see some part of the spectrum normal people can't, or can shift light into the visible spectrum from other wavelengths. X ray vision.
* Insulation might be handy. Without all the ambient heat save convection, they might get cold after a while. Basically the temperature difference between night and day. This would probably just mean wearing clothes that appeared to be inappropriately warm.
# Science/Medicine
Turing parts of something invisible (the ground, a person), but leave the interesting bits visible. What's interesting varies depending on what you're looking for:
* Bullet fragments inside a person during surgery. Imagine an anatomy class taught or assisted by them. Never vivisect again. Instant pregnancy test with gender weeks earlier than a sonogram could manage.
* Tumors/broken bones. No more x-rays or exploratory surgery while they're available.
* Ore
* Oil
* Tunneling animals and insects
* Secret passages
* Fossils
* Help unclog "Morning Glory" (a geyser in Wyoming), and find out why it's so regular.
How valuable would this person's time be? I imagine they'd charge ore/oil all the market could bear, and do lots of charity work for medicine (not all medicine, but yeah) research, etc. Maybe work out some reciprocal agreements for pet projects ("I'll use all your fancy recording and measuring gear over here for my thing, then we'll go use my power[s] and your gear for your thing").
# Combat
* Turn someone's retinas invisible, blinding them.
* Invisible cover + piercing projectile = enemy casualty
* Stealth, derp. How many people will fit inside this radius?
# Astronomy
* Fly them up to the moon. Have them gradually "remove" layers so we can get a good look at everything, like an MRI of the moon. Or turn all the bland ol' rock invisible and see what else is up there... buried alien listening post? Lots of meteors, certainly.
* Most potential applications moved to "limits", below... because daayymn.
# Limits
* How long does the effect last once the object is entirely outside their radius?
* Does a dangling thread count as part of a person? Deliberately unravel a sweater/unspool some wire to keep someone invisible from further away.
* Turning half the earth invisible and exposing the core would allow a lot of radiant heat to escape that would have otherwise been held in. A minutes worth of heat loss might not have a measurable effect, but what happens as the Earth's core starts to cool? Weird new convection currents as a relatively thin section of the mantle cools a bit. "Oops, I just switched the poles... let me do that again to put it back... oh shit (sudden uptick in earthquake activity, and in places one wouldn't normally expect them)".
* Is a city all one thing? In entering a city can they selectively turn various parts invisible? Hold a city hostage by threatening to blind everyone. Or by turning all the street lights, cars, and people invisible.
* Is a solar system all one thing? Removing the light/heat from the sun would be fairly cataclysmic to Earth in the long term. Same result by turning Earth invisible, none of that warming radiation hits us, stuff gets colder. Hey! Combat global warming.
* Is our arm of the galaxy...
* our galaxy...
* our universe...
* our multiverse...
You really need to set limits somewhere. If its something like "contiguous solids and liquids", then they can't affect a mist, or sand, or gravel, but could turn all the oceans invisible.. Or a brick/masonry wall. Hell, human skin could be argued as a contiguous object, while the layers of fat, muscle, organs and bone are different things.
[Answer]
The ability to bend light could make you invisible to the casual observer, but anyone who *really* wanted to detect you could do so without too much trouble. You see, when you bend light around an obstacle, that bent path is longer than the original straight-line path (a 3-foot radius bubble around you would add almost 3.5 feet to the distance). This means it takes longer for light to travel from point A to point B if it passes through your invisibility field. The human eye likely isn't sensitive enough to pick up this small delay, but any sort of laser-based [ranging](https://en.wikipedia.org/wiki/Laser_rangefinder) system would see a measurable discrepancy between its readings and the true distance. These systems bounce a laser off a target like radar. Since the light goes out and back again, your bubble would bend it *twice* and make the delay even more noticeable. No amount of light bending can compensate for this (you can't create a path that's shorter than the natural straight-line path, and you can't make light go faster).
Your enemies would simply deploy [lidar](https://en.wikipedia.org/wiki/Lidar) systems. Your invisibility field would show up as a blob-like distortion. You'd be extremely detectable on lidar while moving because objects behind your bubble would appear to suddenly jump away from the viewer, and then suddenly jump back once you left the field of vision. Your enemy would just wait for fixed objects to start moving on the lidar screen and then start shooting in that direction. Someone experienced with digital signal processing can probably combine the feeds from lidar and from a traditional video camera and see through your invisibility to a degree. Add a sonar system into the mix and you can likely eliminate the invisibility completely.
Side note: Your character should *never* use their powers anywhere near a self-driving car. They rely on cameras and lidar for navigation, and these powers would interfere with that navigation system in a way that's likely to disorient the vehicle and cause an accident.
---
That's not to say this ability is useless, particularly if you're the creative sort. Carry a few relatively innocuous items around with you and you can do some interesting things.
Any fourth-grade kid knows that you can use a magnifying glass to focus sunlight and heat up objects until they auto-ignite. The ability to bend light means that you can take that magnifying glass and more or less put the lens's focal point wherever you want. You could be a natural archenemy for Ant-Man, or the only hero that's not afraid of Mr. Freeze.
Wear a necklace that has a glass prism on it. Prisms are neat because they can take a beam of white light and split it into individual colors. Once you have sources of monochromatic light, you can create illusions/mirages by bending individual wavelengths differently so that the light forms an image when it reaches the observer. It's like painting, but at the photon level.
Carry around one of those small but unreasonably bright LED flashlights. If you ever need to escape from an attacker, blind/disorient them by flashing it directly into their eyes. Since you can bend light, you can even do this while running away and facing the other direction. Similarly, a pocket mirror can be used to create a sun glare effect that you can bend and redirect to temporarily blind any person or camera.
Speaking of escape, you would be able to disable almost any attacker not just by bending the light around you, but by changing the way that you bend the light in a smooth, cycling pattern. The attacker sees the space in front of him rising and falling, shifting position and orientation as if he was standing on a boat in rough seas. His inner ear claims he's not actually moving, though, and that sort of sensory contradiction can induce dizziness, loss of balance, and the sort of [motion sickness](https://en.wikipedia.org/wiki/Motion_sickness#Motion_seen_but_not_felt) that astronauts suffer from.
[Answer]
Simply replace the matter making up your body with "dark matter". Then you don't have to worry about bending light. As I understand it, "dark matter" cannot be detected by any means except gravitationally.
[Answer]
Kaitlyn, heroine of my upcoming series The Vault, can turn invisible via secreting a solution that bends light. It is viscous enough to stick to her skin, while being able to get onto her hair and make it invisible, and it covers her eyes and the insides of her orifices. It's also dirt-repellent, and waterproof. However, she can't see using visible light, and infrared light can be used to see her, so she sees in infrared while invisible.
] |
[Question]
[
I just recently started reading Gulliver's Travels. If you haven't heard of it, it's basically a story about a 1600's era sailor who gets stranded on various islands with strange humanoids. The first one he gets stranded on, Lilliput, is filled with humanoids no more than 6 inches tall, with everything on the island to scale with them. And this got me thinking. What would happen if you got some stone-age Lilliputians and put them in our environment? A few clarifications:
* We are assuming that this iteration of earth is untouched by humankind.
* The group is about 100 strong, and they also have basic supplies (food, water, spears, clothing, etc.)
* They are dropped into a temperate, highly forested area, likely somewhere in America.
* By progress, I mean technological progress. How far would they go? Bonus points for how they would manage resources.
* My main question is how they would survive and progress in this world many times larger than them. I don't want it to be intricate, just a basic overview.
[Answer]
## Problem: 1/12th size is not 1/12th power or force
Their main problem, as noted in the other answers (or comments to them), is that force/power does not scale linearly with size. A 6 inch humanoid may be able to carry a toothpick-sized spear, but it won't do much with it - it just won't have the strength to pierce even skin, let alone fur+skin+fat on a rat or similarly-sized animal trying to eat it.
## Using brains and teamwork to replace muscles
Now we're thinking smart little humanoids. There ARE ways to get around that issue with enough effort and knowledge. A group of Lilliputians could concievably operate a complex system of levers, pulleys and gears to wind up a scorpio (spear-throwing ballista-like siege engine) that would look like a small crossbow to a normal-sized human. With this, they could fend off smaller predators - hopefully they're beneath the notice of any bears. Mechanical systems like that would also allow them to handle fuel and ores in quantities that make using metals feasible.
So the question is then, do you allow them to start with technology (or at least knowledge of it) far beyond your average stone-age person? Or if not, can they somehow survive long enough *and* produce excess food enough to afford thinkers to tinker until they can come up with the ideas and principles, *and* do all the work needed to create the first machine that goes beyond a curiosity?
Pulley systems would be somewhat easy to discover - at their size, a single plant fiber or some discarded animal hair would make a good base for a "rope", and three conveniently grown tree branches (polished with pebbles to reduce friction) could get them a 2:1 pulley system. A group of Lilliputians tying a rock to a rope, pulling it up as a team effort, and dropping it on a walnut might be able to crack it more easily than one little guy trying to carve into it with a teensy tiny hand axe for days. If they manage to scavenge up some bones, they could get to their marrow more easily this way too. So there's incentive and reward for discovering basic mechanics, which might make them view tinkers favorably and invest into new ideas too.
Levers too are fairly obvious - a twig with a rock as fulcrum may let your group of gatherers turn over a rock and get at the tasty worms and grubs just below it.
Gears are more challenging - you'll need a stationary settlement to really make use of them. Other commenters note that without sufficient protection against rats, foxes, cats or what have you, such a settlement would be seen as larder for any predator who notices them. If the Lilliputians are nomadic prior to the discovery of enough mechanical knowledge and skills to fend off small predators, this might be an impediment - but not an insurmountable one.
## A bit of culture to make it work
What won't work is the fairy tale idea of one guy sitting down, whittling up some gears and rods and other pieces, and putting it all together in a tribe-protecting mini siege engine. Even if we let Lilliputians live human-long lives rather than the much shorter ones they SHOULD have at that size, and then replace long trial-and-error with divine inspiration or knowledge passed from previous generations, it would take much too long to (somewhat) precision craft all the mechanical pieces needed to make it work. Oh, there may be legends of just that happening later on to glorify tinkers and encourage young ones to follow that path, but they'll be exaggerations or entirely made up.
What I could see happening however is a big cultural emphasis on tinkering and teamwork - the two things that let them overcome challenges and thrive rather than just live in constant fear as prey animals. Small nomadic tribes carefully evading predators might meet up in an inhospitable place (where no predators are interested in hunting) every year for a few days, bringing their newest ideas, interesting materials, and if the tribe has been prosperous enough to afford working on those instead of gathering food even pre-fabricated parts. Knowledge would be exchanged, those with the best ideas/materials/parts would be most attractive as mates for partners from other tribes, and the tinkers would work together on projects that particularly inspire them for a bit. After the meet, anything too big to be carried along with a tribe gets moved into a small cave (further excavated a tiny bit every year) that gets sealed until the next meeting with pebbles, mud, beeswax... to protect the half-finished stone gears and axles and whatnot within.
## Success: a new age
Finally, after decades of work, the project laid out by the forefathers is completed. A huge (for Lilliputians) pile of discarded gears that broke or were just off the needed size by enough to not work proclaims the generations who went through trial and error to get us this far. Tiny gears carved from rocks or bones in painstaking work, lubricated with fat scavenged from what predators left after sating their hunger. Ropes operated by teams of Lilliputians pulling up counterweights or directly putting tension on the great machine. It takes minutes, maybe even hours - but finally a latch clicks shut. A huge spear (well, a small crossbow bolt) is lifted into place by more pulleys. And the machine that would change Lilliputian history forever fires for the first time, with force once thought to be only available to the large beasts. The spear pierces the bark of the young tree that was used as a target, proving that at least if predators can be forced into the right place (by living in caves with defensible tunnels, for example) warding them off or even killing them will be possible.
Plans are drawn up for the perfect location to set up the first permanent defended Lilliputian settlement - it needs to have access to water, but must not flood. The earth must be fertile, the climate favorable, and there should be a place where defensible tunnels can easily be set up. After much debate a consensus is reached, and the great machine disassembled carefully and put back into storage so it can be transported to said location once all preparations have been made there. It will be years of work still, but finally our peoples' hope is in a workable plan rather than only the dreams of the tinkers.
## Bonus: how they got here - surviving as 6-inch nomadic gatherers
This part is fairly easy, I think - at least compared to the rest. Small tribes of Lilliputians forage for berries, scavenge opportunistically, and survive the winter by stockpiling nuts (which would be a pain to break open, but worth it) or mining out root vegetables rather than try to pull them up. Many individuals and maybe even entire tribes will be lost to rats, foxes, birds - but the surviving ones are the ones that learn to recognize tracks of dangerous predators and how to avoid them.
Starting with only 100 individuals as the question states would be hard, a lot of luck would initially be needed. But the stories we hear or read are almost always those of the lucky ones - the hero who finally killed the dragon walked over dozens of charred skeletons on his way through its lair. For every great leader bringing an age of prosperity to their people, dozens more have failed. For every great invention advancing society by leaps and bounds, hundreds of people lived their lives seen as crackpots and died broke without anything to show for their work.
So requiring a little luck for a story is not a bad thing in itself - it only becomes one if the amount of luck is unbelievable, or its influence is so constant that it becomes plot armor. I think our Lilliputians could do it, even if it will take them a lot longer than we might have hoped.
[Answer]
Six-inch humanoids wouldn't get very far for a simple reason: fire. The sticks we use for kindling would be as thick as trunks to them but still only burn for a minute or so, not hot enough to cook meat or boil water or fire pottery or form charcoal or smelt metal. Larger fuel sources would be nearly impossible to acquire (they'd have no way to fell a tree or chop it up) and certainly impossible to control once ignited.
Your colony of tiny people would be, and remain, pre-fire hunter-gatherers.
[Answer]
**Summer season**
The cave is deep, we don't know how deep. There's always worms, that is easy. For food stock, we prefer walnuts. We know where to find these, we dry the walnuts and Bghtaq has to use his chopper to open them..
Mice and rats are everywhere this year. We don't eat mice every day, you're lucky to catch one, these cowards are fast. But if you hit one it will go down.. you don't need a spear, a pebble will do. The other day Mrthaq put his famous sling to good use, killed six mice. It's a good season, we had rain, so we have plenty of mice.
One mouse is good for an evening meal. Dad loves mouse, because his father did and the father of his father did. In our caves, most kids hunt rats nowadays. Use the spear. More thrill, rats can be nasty, but their meat is far better.
Our parents and us do the real hunting together. Rabbits, beavers, otters, badgers.. last year we killed a mink, its fur made a great coat for Mrthaq. Sometimes we go all the way down the hill, for many days. There's a lake. and ducks ! you can surprise ducks in the water, while they sleep.
There's adventure too. When a duck is killed, we may offer it back to the forest. Sometimes we need to feed the fox, when it is hungry. Else it will eat us. Owls or buzzards can pick up and kill anyone of us, but they can't handle us together, armed with spears. Another trick we use is our tunic of yellow/black frog skin, they don't like the color.
**Winter season**
Of course, we can't stay over winter here, the bear will come.. When winter comes, we roll our walnut stock deeper into the cave. There's water and sometimes fish, but it's dark. No fun.
Sometimes I wonder.. our parents *say* there is a bear. We've never seen the bear ! and sometimes I suspect they just make up the bear, to take us out into the deep cave every winter. Parents seem to always prefer doing things like they did before.
[Answer]
6 inches tall makes them the length of a wood mouse and as "humanoid" likely would weigh much less. Certainly under an 25 grams. This would make most forms of aggression moot.
For example, a spearman would have to be able to generate about 3N of force on a spear honed to the point of a hypodermic needle to puncture comparatively soft "real world human skin". One of these hunters standing on their spear with their full weight would only produce 0.25N
They might be able to feed on soft grubs and slugs but I think their only chance would be to become nomadic berry/fruit gatherers.
I say nomadic as if they were to settle anyplace for any duration longer than a few days, their entire populace would almost certainly be devoured by a predator. An owl, fisher, or racoon is my best bet. If they somehow were able to fend off a racoon or fisher and form a colony, it would only last until a black bear ate them.
So, their best chance is as nomadic, arboreal gatherers who rely on stealth/camouflage to survive with basically no real way to defend themselves. I imagine they would be clustered in small family units and come together as a society only occasionally.
I would not imagine they could progress beyond a primitive hunter gather level.
**Post Comments Edit**:
There was a suggestion in the comments that I don't think this troop would be viable and quite frankly, I don't.
Modern researchers suggest that it *might* be possible for as few as 98 people with guided breeding to seed a new civilization and that is basically what we have here only with a stone age level of advancement.
Their size suggests that most basic machines like the wheel or inclined plain would be superfluous with fire being out of the question due to fuel scaling problems.
Someone suggested looking to capuchin monkeys as a template but these monkeys are four times taller and weight up to 5kg. That is potentially 200 times the weight of a field mouse sized human. They have thick fur, comparatively large canines, tails, and bodies built for jumping and climbing.
Here is how large they are (for later comparison):
[](https://i.stack.imgur.com/Q8aGO.jpg)
A bush baby is a better height comparison and even then they are not lean like people and weigh potentially twice what a lean human would weigh. Here is what we are looking at armed with a toothpick or a corn hair sling and a pebble:
[](https://i.stack.imgur.com/XIoL0.jpg)
Attempting to ward off a family of racoons:
[](https://i.stack.imgur.com/Fa4RZ.jpg)
I know that is more than a single family of racoons, but for reference, that guy is holding a container of 100 hotdogs and that is only part of what he feeds them on a daily basis. That is our entire civilization as a starter course.
Also note that bears will happily tear into rotten logs to eat grubs and bees. A bear might not chase one tiny human (though a fisher would), but if a bear or a gaze of racoons found our town they would likely devour it all at once.
[Answer]
Capuchin Monkeys are probably a great place to start. They're tool using creatures, they will take twigs and stick them into anthills, pulling out the ants that crawl onto the twigs. Early humans may have began to defend themselves against predators with thorny branches, so this isn't too much of a stretch from the sorts of tools we've seen smaller primates use. Someone else posted the difficulties making fire, so your cradle of civilization is probably going to be somewhere near a volcano with a lot of natural kilns and rocks that are easier to start fire with; you are not going to be able to make a lot of friction. The advantage these creatures have though is going to be numbers; with a greatly reduced size and being lower on the food chain, the carrying capacity for these people is going to be humongous. Given this starting point and the easiest directions to go from here - you're more likely to find hot springs used as a power source before water wheels - I am imagining a society that evolves a lot like the Gorons from The Legend of Zelda. They would need to develop their own architecture, but there is a much wider variety of naturally available habitat. Clearing out an anthill or prairie dog colony, for example, would create a habitat or even a starter mine for resources. Although mining itself would be a little more rare at first ironically enough, since the topsoil layer would effectively be a lot thicker.
Where I think this society would be significantly held back is sailing. It would simply take longer to make trips across the ocean, which would mean stockpiling more in the way of supplies. I think the society would probably be well into the industrial era before it was able to make seaworthy vessels. They may even discover air travel before they reach this point; airplanes to us may be as new as ocean liners are to them.
[Answer]
A couple principles are critical in your worldbuilding here: First, the anthropic principle, aka observational bias, second, the cube-square law, and third, cellular biology.
The anthropic principle says that our observations of the way the world is are dependent on our being here to make those observations. You ask "how they would survive and progress in this world many times larger than them"... this ignores that **the world already is many times larger than humans.** Oceans are wider than our ability to swim, ore veins are deeper than our hands can reach, orbit is faster than our legs can run....but we still tamed all of those. It's a natural bias to project your own expectations into a hypothetical universe where this absolute difference of height to planetary diameter of about 12 million meters or this ratio of 1:6,000,000 is off by a comparatively small amount, a factor of 100. A 'regular' human would not be regular to this world, they would be an unusual Godzilla-sized giant to the small humanoids. Just as we understand trees to be typically much larger than humans, unable to be stepped over or uprooted by hand, so too would they understand what we'd consider a small bush to be larger than them. We'd consider a 1mm grain of sand to be nigh impossible to pick up or to see, to them it would be as easy to manipulate as a baseball.
There are a few scale-dependent factors from physics that would make their life or biology a little different from ours. One is the cube-square law. Volume scales with the cube of length, while surface area scales with the square of length. Weight scales with volume, while strength scales with muscle cross sectional area. A related condition (because respiration and heat loss scale with lung and skin area, but cellular metabolism scales with the number of cells) is two-thirds metabolic scaling due to Kiebler's Law; the tiny humanoids will consume a lot more food per unit mass. However, they do not need to have a fear of falling; they're strong enough and their terminal velocity low enough that they can jump from any height, similarly, heavier-than-air flight is far easier for them.
An important question is whether you want to attempt to scale your humanoids to have scaled cellular biology. You've already said that you want them to be of comparable intelligence, but their skull cavities can contain far fewer neurons than ours. Are other factors like the speed of nerve impulses, the dimensions of DNA, the number of photoreceptors in eyeballs, and so on scaled as well? A related but probably story-critical question is whether they perceive time at the same rate - Their neurons are shorter but hypothetically just as numerous; your reflex to swat a fly on your leg travels up your whole spinal column and back down your arm at 100 m/s, a shorter nerve (like that between the fly's eyeballs and its brain) can react far faster; the connection of nerves in your cerebulum that define your processing and concept of neural impulse velocity and is currently slowly working out the implications as the signals clock back and forth 150mm across your brain, what would life be like if those signals only had to go 1.5mm?
A potential reference work is [Dragon's Egg by Robert Forward](http://investigacion.izt.uam.mx/alva/DragonsEgg.pdf), which considers aliens of human-like intelligence called "cheela" who live by very different biology and very different physics...on the surface of a neutron star. Their brains are molecular, not chemical, they see in X-rays, gravity and magnetism are crushing, irresistible forces to them.... their lives and culture are far faster than ours.
[Answer]
## To begin with, they would have to rely on poison
Somehow the diminutive humanoids discover poison, whether they harvest it from plants or other animals.
This will get them past their biggest barriers to survival. A single lilliputian with a sufficiently poisonous arrow could take down moderately sized prey at least.
### Fire
Fire can, once started be maintained, but would be hard to transport. They would not find it hard to make sparks from small pieces of stone or pyrite. Ancient humans transported fire with (among other things) [Amadou](https://en.wikipedia.org/wiki/Amadou), but the time it can burn for is limited by size which does not work in their favour.
### Transport
Talking of transport, our lilliputians are going to struggle with ground travel, but excel at air travel. If they observe various gliding animals in the forest over time they may learn to mimic gliding using simple tools. For instance, sugar gliders are about 6 inches in length, and about 3-5 ounces (~120g). Even though our humanoids probably won't be adapted to gliding, they will fare much better than full-sized humans.
### Tools
Most tools needed, like pulleys and Archimedes' screws, would scale or could be operated in groups. It's unlikely this would pose a serious problem to them.
Smelting would be a challenge, but they could get access to tin and lead, which have a much lower melting than things like copper and iron. It would take almost all their efforts to build a large enough kiln to smelt these metals, but it would be possible. It would probably be less of a commercial matter, and more a community effort.
They could then probably take advantage of steam engines much sooner in their history, because I believe [smaller steam engines](https://en.wikipedia.org/wiki/Model_steam_engine) will operate at lower pressures than larger ones. Perhaps they make an [Aeolipile](https://en.wikipedia.org/wiki/Aeolipile), and it is much more practical at their scale than others?
[Answer]
**6 Inch tall humanoids**:
Are we talking about actual living creatures, or artificial forms of life?
# Biological Humanoids
A 6 inch body, using our own body's ratios of 1/8 to 1/7 head to body, implies that their heads are 0.75 inch head to 0.86 heads. Now assume that the brain occupies about 3/4 of the sphere that is the head, let's simplify this (yes I know it isn't accurate) and say that we are working with a volume of a sphere which has a radius of 0.60 inch. I'll conver to metric now; that's 1.524cm and it would give us on average a volume of 14.82cm3.
In comparison, a modern human has on average 1300cm3 to 1500cm3, a rhesus monkey has 89cm3, a locust has 6mm3 (not cm3) and a pigeon has on average 2.18cm3.
Now, there's two important factors here to consider;
1. pigeons are extremely intelligent (as are other birds) capable of learning, memorising, generalising and even using tools, because their brains are very advanced, and
2. Elephants have larger brains that humans, yet aren't as intelligent, mostly due to the lack of high neuronal interconnectivity.
So, roughly speaking, our humanoids are considerably smarter than pigeons, yet dumber than monkeys.
So, how can they survive in our environment? Looking at the evolutionary mechanisms that enabled the survival of other species is probably the safest bet:
1. **Learning by observation, example and imitation** where knowledge is transfered from one humanoid to another, across their community or group, and enables them to survive and advance, would be a critical factor.
2. **Organising in communities** and groups would also be a deciding factor, smaller groups would most likely perish as larger or same sized predators would easily wipe them out. A location that offers little competition in the form of predators would be ideal too.
3. **Local or Nearby Resources** would be a requirement; food, water, raw materials, anything they can make use of to survive in a simple and easy way.
4. **Technological advancements** would probably dictate long-term survival, e.g., if there will be generations that last long because technology played an important role to their survival, you only have to look at humans to see how important that is
5. **Cultural developments** would also play a role; are they able to speak, write, communicate, store information, or are they really primitive?
# Artificial Life forms
This is an entirely different conversation, because we do not know what their intelligence capacity and limitations could be. Regardless of their size and brains, an electronic (or similar) life form could sway one way or the other; they could extremely intelligent and demonstrate a hive-like intelligence, which could make them comparable to humans or super-human intelligence, or they could be simple automatons, barely able to survive.
If the later, they would most likely not be able to copy or procreate in any form, and chances are they would have serious trouble maintaining them selves. Eventually, they would either need to evolve to the point where they are either reproducible or self-maintenable (kind of like a Von-Neumann Replicator) or perish, regardless of wether they can survive in the short term.
On the other hand, an evolved artificial humanoid would most likely be capable of not just surviving, but self-modification, evolution, expansion and overall self-improvement, to the point where survival would not really be an issue (again, look at modern human society to get a faint idea of what that could possibly look like). In this case, all bets are off, we have no idea how that could go; they may be able to increase their body size, give up their physical embodiment altogether, create other artificial bodies for them selves, etc.
] |
[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/210124/edit).
Closed 2 years ago.
[Improve this question](/posts/210124/edit)
Imagine you're an all powerful god and you want to reduce the likelihood for unsavory behavior like crime, war, and disaster capitalism.
Without taking away free will, or micro managing all actions - what sort of objectives would you prioritize and then how would you magically enforce them?
Example: No-Game-No-Life god implemented a system where any physical aggression would start a game where the win was enforced magically. This did not however create equity or stop predatory behavior from being part of the world dynamics.
I'm looking for an answer that gets to the root of why non-consensual forms of power are hard to police, and suggests a novel way to steer anyone away from that behavior. I'm looking for **aggregate behavioral shifts**. The challenge and *contingency* is that your answer cannot take away free will.
What global aspects need to be influenced? What methods would be most effective in implementing those influences? Feel free to pull from fictional or real world examples to make a case.
[Answer]
# Dying Curses
There is a long and culturally almost universal tradition of a dying person (without any magical abilities) being able to make a righteous curse against those who are responsible for their death. That is, "*I curse you with my dying breath*".
Oddly, I know of no magic/fantasy stories, series, movies and hardly any RPG game-system that have ever taken this concept up as a primary element of their magic system. I have long thought that the primary reason that no media source wants to touch this culturally widespread trope is because it would make many of the premises of their stories untenable: That is powerful evil forces being opposed by a plucky individual/band doesn't work because those powerful evil forces would've been death-cursed into irrelevance long ago. In short, if you give this much power to the otherwise powerless people, the world suddenly has to pay attention to them and respect them.
Specifically then, in this world the most powerful magic is a righteous curse made by a dying person against those responsible for their unjust death. "righteous" here means that the person(s) being cursed does actually bear some real responsibility for the person's death, and that death must, to some degree, be an unjust death. It will be up to you to determine what the boundaries of that might be, but probably, a case like getting shot by a guard while trying to steal something (that was not rightfully the thief's) would not count. Thus you could specify that innocent guards, honest cops and soldiers defending the (just) borders of their country, probably would not be susceptible to such curses. Further, they themselves may be justified in making their own death-curses should they fall in the line of duty.
There is no magic in this world that can counter or undo such a powerful curse (except possibly some kind of reformation and quest of redemption). It is also up to you to determine what form these curses take: whether they are always just generic (but powerful) cases of very bad fortune or if the person invoking the dying-curse can customize it to a specific nature.
But in any case, these *curses should be cumulative*, that is though even a single curse is significantly bad, the more death-curses laid on someone, the worse they become.
[Answer]
Many buddhists posit that the self is an illusion. Long story short, according to them the whole notion of self is the source of all human suffering.
If you wish everybody in your world to be selfless, you may very well break the illusion of self for the people in your own world. How you go about this is up to you... Maybe everybody shares a single hive mind, maybe they just share feelings so that when one of them hurts, everybody hurts. But as long as causing suffering immediatelly brings onto the causer just as much suffering and everybody is aware of that, your people should chill.
[Answer]
Anything that would make the world more like the technological magic of today.
I assume your setting is somewhere in the medieval period, then you can look at a graph like this one <https://ourworldindata.org/grapher/homicide-rates-across-western-europe?time=1300..2016> and see that homicide rates in Europe decreased 50 fold since 1300. I think you will also agree that Europe is now fairly peaceful compared to how it was in the last centuries.
Therefore I'd suggest that your magic system does the same thing that technology does. It should be learnable by anyone. It should allow for the easy creation of food and shelter so that hunger becomes a solved problem. It should allow for increased health and particularly reduce child mortality. And it should enable engaging and accessible forms of entertainment.
I think that would be enough ingredients to lead to a form of government and peaceful existence that we have today, but it might also end up as final stage capitalism... If you want to go a step beyond, you can make your magic system scale super-linearly with the number of people conjuring a "good" spell and sub-linear scaling for "bad" spells. This means that a community of people acting in harmony will be mathematically optimal and given enough time that's exactly what will happen. For example say it takes a thousand people to erect a defensive magic barrier, but it takes a million people to break it for an invasion; this will quickly make wars futile.
[Answer]
This would not be easy to flesh out by any means, but how about a system of magic where the magic is powered by truth and altruism? Working out how this might work won't be easy, but with this type of system all magic would fail when its used for anything that doesn't benefit humanity. So healing, creating food, and building things would be easy to accomplish using magic, but harming people or waging war would be impossible. This would also create a dynamic where magic could be easily used to defend yourself against any type of weapon, so you could easily build a society that sees violence of any type as simply being pointless because magic could be used to perfectly protect everyone from any kind of violence.
This could create a society where magic solves every single problem that arises, thus creating a sort of utopian civilization where altruism gives everyone the power to protect themselves from any form of violence without being able to be violent themselves. Their entire society could be based upon improving the lives of others, so peace would be a natural side-effect of how their society functions. Violence and war could even be considered alien concepts beyond their ability to comprehend because from birth they are taught that the only way to have any kind of power is to be altruistic and use that power to the benefit of everyone.
Anyone who wants to use power to conquer, will need to use brute strength or technology to attain that power, but it would be useless against the magical defense capabilities of anyone who accepts the altruism-based magical power and uses it to make the world a better place for everyone.
[Answer]
This is boring for a Story, but basically **unlimited "resources"**.
If magic allowed everyone to have everything they want, there would be no need for conflict. Now, Humans are also a resource. Some people, might want to have slaves.
To solve that, your magic must be able to create "fake" humans, that would be indistinguishable from real humans, but not be alive/conscious.
The easiest solution for all of this, is that magic allows every human to have his own **personal Virtual Reality** in his mind, while his body is in a safe stasis.
You could go for a less perfect system, with "just" easier access to material resources. One of those systems, like mentioned in another answer, is basically our modern world. You can add on to that. Maybe food and shelter is unlimited. Maybe there are pocket dimensions, so land is unlimited.
[Answer]
Ways to help:
Magic that is defensive in nature. You can't blast with fireballs, but you can protect against napalm.
Magical defenses against theft. Ways that honestly obtained property can be identified.
Magical ways to detect truth vs lies.
Magical objects that can serve as just judges and enforce judgments. Alternatively, public servants voluntarily take a magically binding oath to do justice-- though even if they can walk away at any time, that may fall afoul of your freedom constraint.
[Answer]
Since we're looking at a method a deity could steer people away from bloodshed and not necessarily eliminating it entirely:
**Luck Manipulation**
Simply put, if you attempt to do things that benefit others, the odds will tend greatly to your favour. If you intend harm unto others, your fortune will swing the other way.
Say you're growing crops to feed your poverty stricken neighbours, the magic of this world will all but ensure good seasons and an abundance of good produce. Try and steal all of the food for yourself and luck will turn on you. The evening you try to break in will just happen to be the one the farmer happens to take an impromptu stroll, your thieving equipment will in all likelihood break and/or there'll just happen to be an exposed tree root that's difficult to spot that causes you to trip and break your ankle.
People truly determined to harm others may find a way do so anyway, but crimes motivated by greed, lust or desire for power would become almost impossible to pull off successfully. And moreover, the good fortune that accompanies kind deeds would seem the more convenient road to wealth and influence.
[Answer]
# Empathy in a powerful and compelling form
@LSerno's answer comes closest to this, but differs.
Suppose a god could ratchet up empathy. You meet or spend time with another living being (person or animal) and you feel how they feel. Make that, but intense enough to be compelling.
This isnt entirely fictional either. There are plenty of people who feel/pick up on others emotions and in effect not just have a sense of them conceptually, but actually feel them in their own neurology. Its commonplace in very intense emotional situations - to take a dark example, if a child is in terror and agony and screaming, their parent will often feel uncontrollably rouched by that sense of terror/pain and unable to not rush to help and fix it. Equally when a lover smiles and feels happy, so often their partner picks up on it and feels that emotion too. So it's not exactly scifi or "woo-woo".
My suspicion is that if empathy was inescapable - of you literally couldn't do a thing without feeling for real, in yourself, how the other/s in the interaction felt or would feel, then you'd learn early in life to avoid anything if possible that would be at the least, avoidably hurtful to others.
[Answer]
**Two things in people's perceptions:**
**Strengthen pair-bonding** between partners in relationships. Arguably love exerting it's influence is a loss of a measure of free will already, taking that a little further will increase successful relationships, forestall jealous rages caused by infidelity and have the effect of increasing the emotional balance and well-being of offspring. This will inevitably lead to greater community harmony.
**Decrease the suspicion** of outsiders/increase the acceptance of a wide variety of customs and styles of art and language. This should lead to less tribalism in general, fewer misunderstandings between people of different cultural backgrounds - and fewer wars, if diplomatic communications are improved as a result.
I guess that makes it "**magic of the heart**" or illusion as sceptics might posit.
[Answer]
## None
If your hypothetical god is devoted to the idea of not micromanaging the people of your world, and of not taking away their free will, and wants a magic system which maximizes peace, or at least minimizes the abuses to which magic would be put, the correct magic system in the world is none at all.
If people use mere material objects in creatively violent ways, from stick and clubs up to nuclear weapons, or even hot and cold, hunger and sleep loss, to war and to dominate and control each other, can you imagine how much creativity they would put into abusing each other with magic?
Unless the magic is an intelligent participant which itself actively puts a finger on the scale of how it is used (and then you're effectively back to your god, or your god's proxy, micro-managing), any solution will be open to abuse and corruption.
Divination which lets defenders know how and when they are going to be attacked also lets attackers know weaknesses in the defenses - or even who would be corruptible to turn on their allies! A global social credit system, displaying who has been the most "good" would likely require very active management (thus failing the not-micromanaging rule), as well as requiring people *know* that the score is accurate. "Yes, it says I have the kind of score a murderer would have. But what if the system is broken? Can you prove that I actually murdered anyone?" Additionally, bad people might be able to recognize "kindred spirits", who would be natural allies against those trying to be "good".
Defensive magic could defend the evil from just reprisal just as well as the just from the evil. (As has been pointed out by others.)
Even enhancing compassion may backfire (even if you could argue that it doesn't trample on free will) - because it is our compassion for the victim who was trespassed against which fuels our hatred for the transgressor, perhaps even out of proportion with the crime!
## Ultimately, the only magic system which could not be abused is no magic system at all.
(Although that's a really boring answer.)
[Answer]
**How about some sort "physical" karma manifestation?**
* If you magically do something evil, evil critters will materialise to impart you some kind of retribution based on what you just did (simple example, you hit someone, an elemental spirit manifests to hit right back at you,
* If you do something good, you are somewhat praised (up to you to decide how though, nothing comes to mind)
In this way not only you are discouraged to use magic for evil deeds because you have to face the consequences immediately and proportionately to your action, but also you are encouraged to do good.
I used 'karma' but you can use whatever you want, just something that interacts directly with your soul, so that the intentions behind the actions are clear.
[Answer]
# Magical feedback.
"The spear in the Other's heart is the spear in your own: you are he" is a traditional Vulcan saying attributed to the philosopher Surak.
Your omnipotent god might then decide to make this literal. If you cause harm, you feel that harm. You can commit homicide, but at the cost of your own life. On the other hand, do good, and *feel* good. By loving someone, you add to their health and well-being, and those loving you give you the same benefit.
This effect appears (technologically, but being Clarke, it can be considered magic) in *Childhood's End* by A. C. Clarke - when the Overlords declare they won't stand for cruelty to animals, and ban bullfights:
>
> The Plaza de Toros was full when the *matadors* and their attendants
> began their professional entry. Everything seemed normal: the
> brilliant sunlight blazed harshly on the traditional costumes, the
> great crowd greeted its favourites as it had a hundred times before.
> Yet here and there faces were turned anxiously towards the sky, to the
> aloof silver shape fifty kilometres above Madrid. Then the *picadores*
> had taken up their places and the bull had come snorting out into the
> arena. [...] The first lance flashed - made contact - and at that moment came a sound that had never been heard on Earth before.
>
>
> It was the sound of ten thousand people screaming with the pain of the same wound - ten thousand people who, when they recovered from the shock, found themselves completely unharmed.
> But that was the end of that bull-fight, and indeed of all bull-fighting, for the news spread rapidly.
>
>
>
By the same token, being hated or loathed effectively shortens one's lifespan. Something like this - way more drastic - appears in Damon Knight's *A Reasonable World*:
>
> Well, he *was* a SOB; he could afford to be one, and it came natural, so why not? "Pinky" he told the AI "there was something on the news about rudeness, last week sometime."
> In the holo, a local anchor appeared. "A wave of unexplained deaths in Eastern cities has a few scientists worried. Like earlier victims apparently killed by symbionts, they were mostly men between the ages of thirty-five and sixty, but unlike those earlier deaths, there is no evidence that they were about to commit any act of violence. They were, however, all said to be extremely rude and overbearing persons, who made everyone around them miserable. In other news - "
>
>
>
Once the link between *do unto others* and what *will get done unto you* gets absorbed, from the earliest age, war, crime and negative behaviours will become marginal.
[Answer]
### Divination
Crime only works when it can be kept secret. Wars of aggression become a lot harder to pull off successfully if your intended victim knows you're coming and what your tactics will be. Many of the worst market abuses are only possible due to the exploitation of information asymmetry.
If you want to incentivize peace in a society, *hand out divination magic like Halloween candy*. Make it hard to keep secrets and easy to uncover them. This will end up creating a civilization where openness and mutual trust is considered normal.
[Answer]
**A global available ranking system**
Provide for every person a score depending on their deeds and make this score available to everybody on request. For example cheering up a friend gives 1 point, giving a meal to a beggar 3, splashing a person on purpose while driving by -2, torture -1000000. Set the numbers in a way that if several good and bad deeds cancel each other there is still a net gain in niceness and peace. It should be made clear to everybody what kind of points to expect for which deed.
Make it possible for every person on the world to access all scores by magic. One would not need to know the name or another specification to get the score shown. It is enough for the magic to understand of whom the value is desired (e.g. the woman on the other side of the street, the leader of our country). Also provide any desired graphical or statistical evaluation of the scores.
This would allow to compare candidates for offical functions in a reliable way. False accusations might also be found out much more easily for large negative deeds if there is no significant score change of the accused person and if the score of the accusant drops. This will also strengthen correct accusations as the delinquents would have to somehow hide their bad deeds by doing lots of good ones in secret and it will be clear that the accusants believe their claim.
Additionally people are quite a bit competive. Seeing that your neighbor scores higher than you can provide some additional incentive to do good.
One could also provide a score for nations (and other groups like firms). Claiming that a war is just is really hard if starting it drops the nations score in the red numbers. And one can always check which country is currently the most righteous one in the name of the god thus also leading to some competition in the right direction.
As there is no list of the deeds taken into considerations (except if requested for oneself) it cannot be used to spy but it still allows to identify villains and saints without any doubt.
[Answer]
## Mutually Assured Destruction
There is a very simple magic spell which allows the caster to kill a person and anyone that person loves. But the spell has a weakness: It allows the target of the spell a couple minutes to decide if they want the same thing to happen to the person who cast the spell and kill them and their loved ones too.
That means using this spell would be a surefire way to eliminate someone you hate, but also suicidal. The only people who would ever use this spell are those who were brought in such a desperate situation that they have nothing to lose anymore and no other viable goal in life except revenge.
Which means it would be a very bad idea in this world to bring anyone into such a situation. Starting a war and thus causing countless people to lose everything because of you would make it very likely to end up at the receiving end of such a spell. It would also prohibit lots of other abuses of power which could leave one or more people desperate and with nothing to lose.
[Answer]
## A village/ city building game.
People who become leaders can very quickly use resources to build up cities and settlements and empires. There are harsh penalties for war, as it's not a war magic system, and crime.
If people can use diplomacy and trade and negotiation to advance they can advance much faster than if they hurt others, and there's no city options for building barracks or warlike things.
In a city, there are also harsh penalties to individuals who are antisocial.
In addition, defensive measures are very cheap. It's much easier to turtle up than to wage war.
## Philosophy bonuses.
Libraries are an easy to set up building, and in each library there are lots of books on philosophy and morals and religion.
Any person can read them to learn morals. They can gain substantial boosts and improvements from learning such things and fulfilling ethics related quests.
[Answer]
## A few thoughts:
This is a REALLY hard question to get right, so I'm not sure if there IS one answer to the question. But since the desire is to set up magic that slowly shifts society, I have a few thoughts. Thank you, everyone, for helping me process my thoughts on this one (sorry for the annoying comments).
* **Teleport away from danger:** A spell exists that causes people to teleport away from immanent physical harm. It is typically automatic, so a person about to be stabbed vanishes and reappears elsewhere (details to be determined). A visible magical residual is left behind when this happens, so people can see the person teleported away. A murderer is covered in the equivalent of a dye pack, making it hard to pretend they had nothing to do with a murder attempt.
* **Immunity from coercion:** A spell similar to a geas exists that compels the person (voluntarily) casting this on themselves to defy any attempt to coerce their behavior. Once a person decides to use this, they must feel free of coercion before they can perform an action. The ultimate act needing freedom would be undoing the geas.
* **Divine warning label:** Your god actively involves itself with people, but only in an advisory nature regarding magic. If a person will use magic that decreases the freedom of another, a cherub shows up and tells them they are defying the best interests of the person they are casting at. So a person cannot claim to be working in someone else's best interests, but they are not stopped from doing so.
* **Obfuscation:** This prevents others from spying on a person or monitoring their thoughts. It is automatically broken by intent to harm others. The intent is determined by the user, so if they actively plan (not just think angry thoughts) to harm others, it dispels.
* **Birth control**: Freedom from unwanted pregnancy is critical for women's freedom (thx RonJohn). All people are infertile unless they personally desire to be fertile. This can't be coerced - they must desire to have children before they can. Threatening a woman that they need to have children doesn't work. This is so basic to the magic system that anyone who can cast automatically has this applied (no choice - yes, that's ironic).
* **Household sprites:** This magic makes basic labor easy. Happy worker sprites manifest and do work for people. This is not universal, so people must still control the sprites (a couple of nobles can't eliminate their work force and summon an army of sprites, but the workers can perform other tasks). The caster must be happy to perform this spell, so forcing them to work disrupts the magic. Employers keep employees happy so as to increase the productivity of the sprites. Excess drugs and alcohol also disrupt the spell.
* **Protection from starvation**: Thx csiz for the starting point of this one. While not stopping hunger, this prevents starvation. people may not have enough to eat, but they do have enough to survive. So no one can starve to death, but it isn't pleasant (providing a motive to work/produce food). This also helps counteract the reduction in fertility due to the birth control magic.
* **Spells causing harm must have a good reason:** Any spell capable of causing harm to others (as determined by the god or angels) is powered by kindness and mercy. The only people who can practice this "black magic" are the kindest, gentlest people (and thus the ones least likely to be able to use it). So an angry dog is driven away from attacking a child, while a killer is powerless to harm a fly. Alternatively, these are conjuration spells (requiring an interceding divine being) who can then exercise their divine judgement as to the justification of the spell and how it is carried out.
* **Universal magic**: Everyone gains access to some or all of these basic spells at puberty. Fancy stuff will require additional practice but not special knowledge, and even fancy spell casting shouldn't be able to interfere with these basic abilities.
Nothing short of coercing the nature of people will stop all magic from being abused. But fundamentally, you are giving control of their own reality to individuals. To thine own self be true.
[Answer]
**An armed society is a polite society.**
If you look at all of the mechanisms by which robbery, rape, and murder are conducted nowadays, you will see that in most cases the perpetrator has the upper hand when it comes to brute force.
So you institute a magic system where *everybody* has the same ability to put the hurt on someone.
This raises the risk of the aggressive use of force to the point that the people electing to use it either change their minds or their criminal career is cut short when an intended victim turns the tables on them.
[Answer]
I think a big part of violence between country, ethnic groups, companies, and even indiviuals that is happening right now due to the inequality of access to resources. Food, shelter are the most basic, follow by clothing. There is thing thing I read in this journal that says the five basic need is "survival, belonging, power, freedom, and fun" [Our Five Basic Needs: Application for Understanding the Function of Behavior]. Even if you place restriction in people's behavior, they would still try to find loopholes to exploit. (Just like what Jedediah said). So if your god can use magic to fulfill these needs, people will have less need to fight each other.
Some example will be:
Enough food for everyone to have more than just "barely not hungry" feeling in their stomache.
Enough shelter for everyone to have a roof over their head.
Enough raw material to supply people's need.
Enough energy.
That being said, there might still be conflict even in post-scarcity world. (Example being the world of Gundam 00). In that case, you need to support people who champions seeking mutual comprehension and promoting love and peace. This method follows your rule because it is not your god that is doing the social engineering, it is the selected champions.
[Answer]
Grant all humans telempathy (tele-empathy). It will have three manifestations:
* a short ranged, constant broadcast and reception that cannot be suppressed. Humans cannot stop themselves from feeling the emotions of the people around them.
* a longer ranged targeted transmission to the person who caused another to experience an emotion. The jackass who cuts across 6 lanes of traffic because they haven't technically missed their exit will have empirical evidence that dozens or scores of people are somewhere between annoyed and terrified thanks to their jackassery. This requires that the sender sincerely believe in the moment that the recipient is responsible for the emotion being communicated, and can't be used deceptively.
* a global, extremely focused query of one person the user can see and hear, e.g. a "Live" TV broadcast or Internet stream (transmission lag and delays handwaved because I'm God in this senario), so politicians and pundits cannot knowingly lie effectively to their constituency.
Lying becomes functionally impossible. The very idea of a conspiracy becomes absurd. Hurting others becomes counterintuitive, because one is also hurting oneself. The anguish of one's fellow humans becomes undeniable, because that anguish is present in one's own mind. Perpetrators feel their victim's distress and the scrutiny of bystanders, who themselves are more likely to take action when they know they aren't the only ones who know something is wrong. Moral justifications of inequitable structures wither in the face of the undeinable convictions of those harmed by them. Humans are forced to acknowledge the humanity of their fellow humans.
Over time, people learn what things hurt the people around them, and stop doing those things. Some romantic relationships fall apart, others form with unprecedented openess and honesty. Discourse becomes less acrimonious, as the sincerity of all participants is above reproach. Misunderstandings become increasingly rare, and accidentally harms are easily forgiven. Society becomes increasingly equitable; helping others literally feels good. Humans ultimately adopt a philosophy of doing minimal harm, while working to eliminate or minimize harms previously thought inevitable. Within a generation, world peace breaks out as the first adults who were born with telempathy abandon tribalism and nationalism.
[Answer]
Many answers focus on taking something away, like taking away the freedom to lie or the freedom to not think about how our actions impact others. I kind of think all of these are, in some sense, "cheating" in the free will department. They effectively remove a choice we have in the current world (I'm assuming you're using the current human world as a baseline.)
The answers that are more about providing more options or things, I think, are closer to the mark, I'm just afraid that they might be mostly boring from a story/worldbuilding standpoint.
So, I am pretty sure that simply **tweaking your world's natural environment** in such a way that
* food is plentiful,
* predators are weak or uninterested in humans,
* the temperature and weather are always moderate enough that shelter is never a life-or-death concern or maybe even not that big of a comfort concern
would significantly reduce motivation to commit crimes like trespass, theft of food, etc. And all of these things also make the world more boring from a story standpoint, I think.
So, if we had all this in our current world, we might still fight about who gets to live on the beach or by the river or on the lake.
I wonder if you might get something interesting where one thing the god does is simply this: **make it easy to leave a society and start over somewhere else**. All of the above--shelter no big deal, gathering food and defense from predators trivial, etc, would contribute to this. But one thing that could really reduce conflict would be if you could just take the people that agree with you about how society should be and go do your own thing without a huge cost. In our world with finite arable/desirable land and difficulties in having reliable food sources and shelter and such, that's practically impossible to do.
But your world doesn't need to have that restriction. Maybe **your world is the Mandelbrot set, and your people can just shrink down** and find a very similar place to where they were just living but without the neighbors that were playing loud music at night.
A great deal of conflict could be avoided if it was easy to collect the likeminded and easily leave and resume your society without the un-likeminded. A fractal landscape is one possibility but **portals to other equally livable planets** or **a planet that just kept growing and spawning new, equally fertile and equally temperate and equally surfable space**; or any magical element that allowed trivial resettlement on uncontested land.
Stories are usually about conflict and this would reduce conflict. But maybe the conflicts that do come up, in the absence of our current conflicts, would be interesting. Think about social media--people find things to fight over, like reach and reputation and each other's attention and so on and it's essentially completely free form and resource-scarcity free. So maybe that's what becomes interesting; what do people yearn for and, eventually, fight over when basic necessities are abundant.
[Answer]
**Expand Gender Identity**
Some feminist thinkers argue that crime, war, and capitalism flow from a social system that effectively forces people with male or female bodies to identify only as a man or a woman. Those identifying as men receive a higher status, a kind of caste system requiring unnatural violence to sustain, which is enacted through social institutions and cultural affirmations. In this world, men must compete and dominate in order to maintain their privileged status, and crimes and direct violence often result from failure to do so, both within intimate relationships between castes and among men themselves.
Using this idea, an all-powerful deity might prevent people from viewing themselves as men and women all together, and instead as individuals of many possible genders (including men and women). Doing so might ease the tension those of the men-caste feel, the violence those of the women-caste feel, reduce crime, and allow for exploration of many new ways of being and co-existing.
] |
[Question]
[
All right, in this fiction there are airships, they're not like blimps or zeppelins, they're much more like the fantasy-esque "age of sail ship that floats", cool and dandy. With their creation, some people in the air admiralty of a nation thought of creating airborne troops, with parachutes (which I was surprised to learn to have been first imagined long ago, 2000 B.C. in China, first drawn in renaissance Europe, and first tested in the 18th century) so here comes the question, would it be feasible?
Before answering, consider the following:
1. The airship's average altitude is 820 feet (250 meters), and it tops on about 900 feet (275 meters), for... reasons. Also, note that this is altitude relative to the ground directly below the ship, not sea-level or anything.
2. Airships travel averagely at speeds of 20 knots (37 km/h or 23 miles/h).
3. Parachutes here are made of silk, similar to those seen on early-WW2, before being replaced by nylon.
Please warn me if there's any missing essential detail, and feel free to drop a (much needed) advice.
Also, here's a little bonus question, in this fiction, armor has enjoyed an extended longevity, it can still be effective against musket shots and projectiles, and because of that, many soldiers wear metal armor. Would it be possible for a paratrooper to wear armor, maybe not a full plate knight armor, but at least one that covers the essentials? Or would it be too heavy for the parachute or simply too unpractical on the situation?
I think I found another possible obstacle: The altitude. If they deploy their 'chutes at, say 650 feet (200 meters), would it be too low?
[Answer]
Leonardo da Vinci's parachute was conceived in the late 1400's, and modern reproductions (made of linen BTW) work just fine.
[](https://i.stack.imgur.com/A4j3d.jpg)
*Reproduction of Leonardo's parachute*
The difficulty with early parachutes is they are simple devices for deceleration. There is no capability for steering the parachute, and control is going to rise in difficulty as the amount of weight increases (i.e. jumping in armour). The result will likely be the jumpers augering in and suffering injuries to the legs, backs and joints, immobilizing a large fraction of the jumping force. Non steerable parachutes also ensure the stick gets scattered across the countryside, reducing the effectiveness of the jumping force. Unless you can muster an overwhelming number of jumpers, or otherwise draw the enemy away, they will be rapidly set upon by the Cavalry, who do not suffer from many of these issues.
The other issue is *how* the parachute force is to be deployed. Jumpers, despite a lot of romantic nonsense, are a supporting or auxiliary force, meant to arrive unexpectedly on the flanks or rear to pin or disrupt enemy forces in support of the main body of troops, who are advancing in a conventional manner across country. Jumpers have limited supplies and are totally reliant on resupply from the air, or the rapid linkup with ground troops. If this does not happen, then you could end up in the position of the British Airborne in [Operation Market Garden](https://infogalactic.com/info/Operation_Market_Garden) ("[A Bridge Too Far](https://infogalactic.com/info/A_Bridge_Too_Far_(book))"), or the French Foreign Legion paratroopers in [Dien Bien Phu](https://infogalactic.com/info/Battle_of_Dien_Bien_Phu) (For a terrifying recount of the disaster, read [Bernard Fall](https://infogalactic.com/info/Bernard_B._Fall)'s book "[Hell in a very small place](https://www.worldcat.org/title/hell-in-a-very-small-place-the-siege-of-dien-bien-phu/oclc/2571399)").
However, given the parameters of the airship, you could bypass the paratrooper phase altogether and go for "Air Assault" instead. The ships approach the LZ, fire canister, grapeshot or similar rounds to clear the area and then simply land and disembark the troops. Troops can run off the airships fully armoured, and with more supplies (even horses, if desired). They will land as complete units and be much more capable and effective than scattered paratroopers (this is particularly important with the muskets available in that era). They can even have effective "gunship" support in the form of airships overhead using cannons or sharpshooters firing down on targets on the ground as the dismounted troops advance. However, much like paratroopers, airmobile troops still are adjuncts to the main force, and are still limited by logistics, size and mobility once disembarked.
[](https://i.stack.imgur.com/oGXho.jpg)
*A platoon of air mobile infantry deployed by Mi-17*
[](https://i.stack.imgur.com/wGdAH.jpg)
*In the 1700's, you would be disembarking Cavalry or Horse Artillery*
[Answer]
Your troopers do not have much vertical distance to work with. But they have a lot of forward momentum to work with. Your soldiers might be better off with gliders.
[](https://i.stack.imgur.com/JEgNt.jpg)
<https://forums.spacebattles.com/threads/modern-military-gliders.537943/>
You could have them be paragliders or something like hang-gliders. The cool thing about gliders you can steer is that you can translate some of your forward momentum into opposing your fall. You can pull up and turn forward momentum into upward momentum. Your soldiers would drop out of the ship and open their gliders, tracking along below the ship for a while. They could pull up right before they land.
[Answer]
Yes, for the reasons you mentioned, parachutes would be **technically** feasible in the 1700s, because of silk cords and chutes. The problem is that it would requires a **lot** of silk, and silk was #1 expensive, and #2 quite possibly made by your enemy.
Thus, while rich young nobles could jump out of balloons for fun, outfitting a battalion (bigger than a company, but smaller than a brigade) would be practically impossible. Of course... if you've got flying sailboats, you could handwave an adequate supply of silk, too.
Regarding whether you can wear armor... the heavier the thing falling out of the sky, the bigger the parachute needs to be. At some point, though, they'd become too big and bulky to wear, and the deployed diameter would be too great for lots of troopers jumping at once. Thus, I'd stick with padded leather.
[Answer]
*I hold my breath for a second, looking to the endless, calm waves below. The sound of the raging wind was almost entirely deafened by that vast blue expanse that rolled over all the way past the horizon, fusing itself with the sky on the distance. There wasn't land to go for if we missed the target. Or was it a perfect landing, or it was death.*
*Checking my gear one last time, I did what I did before several other times. The thing I was trained to do and the thing I lived to do. It wasn't only my military duty, nor the needs of my people that gave my legs the motivation they needed to disobey my instincts every single time I jumped. It wasn't my captain yelling orders nearby, or the loyalty to my comrades. All of those things mattered, of course, but not there. Not now. They were irrelevant.*
*The only thing that mattered was how much I loved to fly.*
*I pushed myself forward, jumping with all my strength out of the launching board. My arms folded to the sides of my body, holding on the metal rings near my hips with a iron grasp. I twisted my body midair, using my legs and my spine to direct myself to the enemy ship several feet down below. An easy target, I told myself. I knew it was a lie, but it was a lie that I needed right now.*
*When my downward speed was good enough, I pushed my arms forward, bringing the rings with me, breaking the fragile glass seals that held my glider in its closed form. I heard the leather unfurling and the several small bronze cogs turning fast as my arms moved into position. A satisfying click made itself audible when the wooden segments that made the attack side of my glider locked themselves in position. I felt the small bump in my movement as the steering tail unfurled itself behind me, giving me the control I would need in my descent.*
*I pushed my right leg forward, pulling a set of ropes that made my tail twist to the side. That movement was mirrored by my left arm, retracting the wing attached to it somewhat and enabling me to enter into a wide spiral, changing my downwards movement into a dash forward.*
*I was approaching my target fast. I could see the individual enemy soldiers running around on deck, shooting towards me and the rest of the small swarm of the Crown's Wings. It was in vain - we were too fast for their clumsy firearms and lousy aim.*
*I could already discern the white of their eyes. It was time.*
*I pulled my arms back. **Hard**. An audible pop of wood breaking later, and my glider was unfurling itself once more - the leather of the wings unfolded itself a couple times, changing its original wedge shape into a more open, wider and longer form, opening itself behind me as a long blue cloak with my team's sigil emblazoned over it. It them jumped upwards, pushed away from my body by the wind. Strong silk ropes made sure it remained attached to my boarding harness, giving me limited but enough mobility for the final landing.*
*My right hand went for my cutlass, while my left one held tight on the unlocking switch in the middle of my chest. I held my breath.*
*As I got closer, still going fast forward, I raised my leg somewhat, making sure to kick one of the enemy soldiers right into the temple before releasing my gliding suit. It kept moving away, right into the sea, its job done and its task finished with perfection. With my cutlass in my hand, I turned myself to find my comrades landing beside me, already ready for battle. A few of us were grinning in anticipation, with our hearts already pumping hard and our minds lusting for blood. The blue below would mean death for anyone that fell from the ship, sure. But We were the Crown's Wings.*
*We were death from the sky.*
---
(Sorry for the broken english!)
Why you don't use gliders instead of parachutes?
[Answer]
At only 250 meters off the ground, troops being "airborne" is not necessary to get them to the ground safely.
Have the troops abseil down from the ship to the ground.
[](https://i.stack.imgur.com/nhaX6.jpg)
The limiting factor of how far down a solider can abseil is the [specific stength](https://en.wikipedia.org/wiki/Specific_strength) of the rope - the maximum length of the rope could be before its own weight would exceed its tensile strength. So, would 18th centurary rope be strong enough to support a solider and the weight of the rope itself?
Yes. Using [tensile strength data of hemp rope](https://www.engineeringtoolbox.com/manila-rope-strength-d_1512.html), a 250-meter long section of 1-inch (25mm) thick rope would weigh about 95kg, but its breaking strength is about 3675kg.
Allowing 120kg for soldier and equipment and a 17th century (soldiers' lives were cheap even up to WW1) safety factor of 2x (assume half actual strength), the maximum abseiling height would be about 4.5 Km (2.8 miles), easily enough.
However the usual modern safety factor is 10x (assume 1/10 actual strength), which gives a maximum abseiling height of about 650m (2132 feet), which is still enough.
The vessel would need to slow its ground speed to a safe value, either by cutting power in still air, or by manoeuvring to fly into the wind (similar to a technique used by aircraft carriers to maximize takeoff and landing airspeed).
[Answer]
As @Graham mentioned Lilienthal gliders could work. They are used (well, one is used so far in my reading) to good effect in the web serial [Airship Flying Cloud R-505](http://airships.paulgazis.com/).
In the story, it is used for scouting and for a single person away mission.
It wouldn't be a stretch to have an entire company trained in their use. Heck, if the lift tech/magic you use can enhance those gliders, you can remove most of their short comings.
The main issue with long distance travel in a glider are the reliance of thermals to gain altitude. This would make gliders more useful for common troops in known territory. You would want highly trained people to lead long distance formations over new territory.
You could have a troop glider similar to what they used in WWII. They were wooden gliders towed across the English Channel and released to glide the onboard troops into position. There are good articles about them on [wiki](https://en.wikipedia.org/wiki/Military_glider) and [ASME](https://www.asme.org/engineering-topics/articles/aerospace-defense/the-flying-coffins-of-world-war-ii).
[Answer]
You might check for some sources in the Napoleonic Wars.
Though probably always disregarded because of technological feasibility and risks there were "plans" (crazy ideas) flying around to invade England with the first airborne drop in history via balloons.
The surprise element alone could have assured the English not expecting this kind of insane operation.
That said, you are entirely dependent on wind conditions and each balloon can only hold a small squad of soldiers and little equipment.
I'm not sure how far those ideas ever got but I heard that someone at that time at least pondered if one can make it work.
[Answer]
Mobility would be an important factor in this type of fight.
The armored paratroopers look good and all but their mobility wold be severely reduced. Also i want to know if there is any magical abilities in your story, this could really change the way the soldiers fight using said parachutes.
You should check out the anime Youjo Senki and its take on airborne troops even if your story doesn't have magic abilities.
<http://youjo-senki.wikia.com/wiki/Category:Mages>
[Answer]
Slightly tangential, but this has impact on the weight your troops would be carrying:
The majority of armour was *not* effective against muskets. Only very heavy armour was, and even then only some sections would be (e.g. breastplate). This is partly why the sword enjoyed a renaissance after the arrival of the musket, because heavily armoured soldiers were very slow targets vulnerable to muskets.
See eg <https://myarmoury.com/talk/viewtopic.php?t=13876>
Heavy armour was also relatively rare, and very tiring to move in.
So armour was probably lighter in your setting than you might imagine.
In terms of the accuracy of dropping unguided parachutes – if your airships are typically at 250m, and likely traveling extremely slow compared to planes, I think the concerns about the accuracy of unguided drops may be largely mitigated.
[Answer]
I don't think anyone's addressed your question about parachutes working at that height.
For a HALO jump, the chute opens at about 600m, according to wikipedia.
According to answers here:
<https://www.quora.com/What-is-the-minimum-altitude-to-deploy-your-parachute>
The minimum opening height for a main chute is 600m; the chute takes about 200m to open, before it starts slowing you down.
Your guys jumping from 250m are much more akin to a BASE jump, which can be completed 'safely' from that height – bear in mind BASE jumps have a significantly higher risk than parachuting, and require a lot more skill.
This is all with modern materials. Whilst Leonardo's parachute worked, it isn't going to perform anywhere near this level, and it's probably safe to assume that you couldn't drop from 250m with an 18th-century-tech parachute.
So I think you're going to be better off with abseiling from the airships.
Abseiling will have many benefits in your scenario:
* a LOT cheaper than parachutes – ropes are reusable, whereas parachutes less so in a battle situation. This is always a plus in wars!
* You can probably probably drop individuals faster (as in less time for each soldier from airship to ground), as the drop is more controlled, and the soldier can control the breaking much more precisely.
* You can certainly drop more people at a time – each rope can probably have several people on it at a time, but even if not, you can drop ropes with a much higher density than parachutes, as you don't have to worry about the canopies colliding
* your soldiers can stop and shoot etc. just before landing
* your soldiers can abort landing and stay on the rope if the landing looks bad – too contested to be safe, too congested, missing the enemy ship / castle walls etc.
* assuming the airship slows a bit as they drop, your soldiers can be much more precise where they drop, by waiting near the end of their ropes until they're right on the castle walls etc.
* you can also exfiltrate via ropes, by the airship dropping ropes to the men and lifting them up. Without much creativity, you could probably work out some way to do this fast and reliably.
[Answer]
While i also love hangliders (they were covered in another answer - they never got the action film love they deserved, the Escape from New York sequel has laughably unrealistic models where they could have gone with the real deal - google hang gliders made from bamboo) i would like to add an heretofore unmentioned way of aero-braking: **gyrocopters**! Hang gliders work by having an airspeed over the foil (and usually also a commensurate ground speed, if the wind is slow) and then, shortly before impact, heightening the angle of attack (nose up), thereby burning speed and gaining lift - if ideally executed, you swoop in hard, and touch down light as a feather. The problem here being the groundspeed in the moments before - you need long stretches of land to execute that maneuver safely. gyrocopters also have airspeed over a foil, but in this case, the foil rotates , so the airspeed does not come with groundspeed. You can go straight down (don't need to, though!)
[](https://i.stack.imgur.com/xRDCX.jpg)
While the real deal has an internal combustion engine to push the gyrocopter forward against an inclined, but unpowered, main rotor, your use case does not entail gaining of height, and could thereby dispense with the motor. All you need is a big rotor (these can be made from good wood, no need for carbon fibres or magic), an axle, and something that conencts axle and jumper, ideally as part of the armor, possibly somewhere in the back.
The rotor could be foldable, so you only need to carry the axle and the two rotor blades (for a 150kg armored warrior, 5 metre (~15ft) blade should do) - They walk around like knights before a joust. The rotor gets fitted shortly before the jump, making the warrior extrmely immobile for the moments before the plunge (also quite joust-like), then they jump, and start gaining velocity - at the same time, the rotor is starting to spin in the updraft. Depending on the blades angle of attack, and several variables having to do with the weight of the blades and the goodnes of the blades profile, the vertical velocity the warrior will end up with may vary. If you allow for handwaving or magic, the angle of attack is even variable - in that case, the jumper could exchange airspeed (=rotation) for lift in the last moments of the flight by suddenly altering the angle of attack of the blades (have the wood torque for some reason, or detach the lower part of the nose-edge,...) - that could be automated (long stick jutting down, triggering the mechanism when the jumper is still in the air) and thereby allow even airdrops of horses or materiel.
I like the visual of armored knights with huge blades on their backs dropping down - you could have some smoke-producing stuff on the blade-tips, maybe even something sound producing like an aeolian. - Ride of the Valkyries, anyone?
To reduce the lenght of the rotor needed, you could also opt for rotors with broader blades (the total area of blade needs to stay constant (actually the broader the blade, the more area you will need for aerodynamic reasons, but lets keep it simple) - if you go for the minimum achievable rotor-lenght, the rotor will look like the old windmills made from cloth and sticks - makes the angle-of-attack change trivial (not needed, though, keep in mind), might ruin the epic visual a bit...
[](https://i.stack.imgur.com/3JjGL.jpg)
] |
[Question]
[
We all know that electrons behave like flowing water, e.g. that electric currents behave like water currents. We also know that modern computers use electric currents to carry out mathematical and logical operations.
My question is:
* Can a computer (a machine that is able of at least carrying out basic mathematical operations) be built which operates and carries out calculations using flowing water or any other liquid?
[Answer]
**It already exists**
There is an entire field of study for this concept, called [fluidics](https://en.wikipedia.org/wiki/Fluidics). Most implementations I found use colliding streams of water to check for relations. While not as precise as their electronic counterparts, these machines are still functional. Here is one [implementation](http://www.blikstein.com/paulo/projects/project_water.html).
Another interesting example is the [MONIAC](https://en.wikipedia.org/wiki/MONIAC), which predicted the literal flow of money between different economic entities. This computer is interesting because it is produces an accurate simulation without using any kind of logic gates. Of course, modern electronics far exceed its accuracy, but the idea of modeling data using fluid mechanics is intriguing.
[Answer]
## It already exists
There is a particularly difficult optimization problem called the "[Traveling Salesman](https://en.wikipedia.org/wiki/Travelling_salesman_problem)" problem (find the shortest path between multiple stops).
>
> The travelling salesman problem (TSP) asks the following question:
> Given a list of cities and the distances between each pair of cities,
> what is the shortest possible route that visits each city exactly once
> and returns to the origin city? It is an NP-hard problem in
> combinatorial optimization, important in operations research and
> theoretical computer science.
>
>
>
Except for smaller number of stops, an exact solution is not computationally efficient. Many approximations and heuristics exist that should yield good answers.
Unfortunately, I can't find the paper that discusses this but some researchers have found a method of finding an exact solution and it involves a "liquid computer". They build a clear plastic model of the routes and then push fluids through the model. The water going through the shortest route makes it to the end the fastest. I assume various dyes are injected so they can determine the "winning" route.
However, there are many attempts at developing [numerical methods that imitate the water flow method of solving the problem](http://www.hindawi.com/journals/aceng/2014/436312/).
[Answer]
Like others have pointed out, such a computer already exists. Not only that, it looks like it was done long before electronic computers; take for example the [water integrator](https://en.wikipedia.org/wiki/Water_integrator), built in the Soviet Union in 1936, capable of solving mathematical problems (but it doesn't look like a general-purpose, programmable, Turing complete device, which is generally what we think of as computers today). Wikipedia claims, but provides no citation for it, that similar computers were used in the Soviet Union until the 1980s.
Another more recent example is [Manu Prakash et. al.'s work on a computer that operates using water droplets](http://news.stanford.edu/2015/06/08/computer-water-drops-060815/), straight out of Stanford University in mid-2015.
Their work, however, is not intended to compete with electronic computers. From the above-linked news article:
>
> The computer is nearly a decade in the making, incubated from an idea that struck Prakash when he was a graduate student. /.../
>
>
> Because of its universal nature, the droplet computer can theoretically perform any operation that a conventional electronic computer can crunch, although at significantly slower rates. Prakash and his colleagues, however, have a more ambitious application in mind.
>
>
> “We already have digital computers to process information. Our goal is not to compete with electronic computers or to operate word processors on this,” Prakash said. “Our goal is to build a completely new class of computers that can precisely control and manipulate physical matter. /.../”
>
>
>
Aside from the news article, their results have been [published in *Nature Physics*](http://www.nature.com/nphys/journal/vaop/ncurrent/full/nphys3341.html) and discussed [in](http://www.extremetech.com/extreme/208086-stanford-has-created-a-water-droplet-computer) [a](http://www.sciencealert.com/engineers-have-created-a-computer-that-operates-on-water-droplets) [number](http://gizmodo.com/stanford-built-a-new-kind-of-computer-that-uses-water-d-1709504695) [of](http://www.popsci.com/new-computer-operates-water-droplets-and-magnets) [different](http://www.iflscience.com/technology/researchers-make-computer-works-using-water/) [places](http://timesofindia.indiatimes.com/home/science/Stanford-scientist-Manu-Prakash-makes-water-based-computer/articleshow/47602032.cms) (note: each word is a separate link).
[Answer]
Some of the other answers mention what seems more like analog computers (e.g. integrators) or seem to involve complicated water pathways to emulate logic elements. However, really all you need to implement a water based computer is a water switch. This is an element in which water flows or doesn't based on whether or not there is (water) pressure on some kind of control input. A visual representation would look almost like a transistor, which is the solid state equivalent:
```
water in
|
\
|---- control in
/
| water out
```
Basically the idea is you have some pipes and they are filled with water to some pressure. Similar to electrons in a wire, the water in the pipe doesn't actually need to flow very much; it is the pressure that carries the signal. The water switch can probably be implemented in various different ways, for instance there might be a spring to force a blocking element (valve) out of the way between the water in and water out, but the total pressure is provided was less than the water pressure. Then, if water pressure is introduced to the control input it overcomes the spring pressure and slides the value shut, blocking off the water from the input and sending the pressure at the output to 0.
Once you have this water switch, everything else can be implemented the same as digital circuits are implemented from transistors. It is of course going to be a lot bigger even with miniaturization because you will run into issues with things like capillary actions and such at much larger scales.
[Answer]
To expand on @Michael's answer, search for "The Water Clocks of Bernard Gitton" -
Gitton is a French physicist and artist who made clocks and digital logic with no moving parts, just glass and water. One of his clocks is at the Indianapolis Children’s museum.
] |
[Question]
[
I had a vision of a creature that touched things, and wherever it touched, it left a mark opposite to the original colour.
For example when it walked across the grass the grass had red footprints, when it touched the wet stone it shone with a patch of white.
**Could such a material**, a liquid or perhaps a dust, **that achieves the described effect exist?**
If yes, how might it work or what would it be made of?
[Answer]
**No, not directly**
The nature of light means that you can't just shift its colour so easily. Each colour is create by a particular wavelength which has an associated energy. There are ways that the wavelength can be changed, but they are limited. Two photos can be combined to make a single photon of twice the energy (this is how most green lasers work), but since the energy of the shortest wavelength of visible light is just under twice the energy of the longest wavelength, this may not be preformed on any light in the visible spectrum and still get another visible wavelength. Fluorescence can absorb one frequency of light and emit another, but typically the emitted light is of lower energy (there is some higher energy light emitted as well).
The next problem is that "opposite" colours only occur due to how the brain reads light signals. The colour spectrum is linear, red->green->blue, purple does not exist, it is simply our interpretation of seeing red and blue at the same time. Opposite colours depend on a circular interpretation of colours that conflicts with the fundamental nature of light.
Now if you want such a creature to exist, you can, but the results must be obtained indirectly. The first option to do this is have the creature excrete multiple chemicals, and purposely select them based on their surroundings. The second option is to identify that a large amount of colour comes from a limited amount of pigments (chlorophyl, iron oxides, copper oxides). If the creature carried a compound that formed various pigments in reaction to the more common pigments it comes in contact with, it could effectively change their colours. This second option would be hard to implement, as each pigment changing chemical would have to avoid reacting the the other pigment changing chemicals.
[Answer]
*Twenty-five years ago I had a friend in the military who told me about glasses he was issued that used passive technology (layers of various materials) to shift the frequency of light, allowing the user to see images at a base frequency that wasn't the original frequency (everything shifted toward the blue frequency, as I recall). For all I know he was explaining a tech he didn't fully understand. However, that's as close as I can imagine to what you're asking about.*
Inverting frequencies is, IMO, impossible. I could be wrong, but it means you need a layer that passes blue light but shifts red to blue, and then another layer that passes red light but shifts blue to red.
And you already have an impossibility, because the effect of the first filter will always be reversed by the second filter. There's no way to tell the second filter, "here's unfiltered light, don't touch the stuff I've already dealt with."
To add to the problem, "color" is actually a range of frequencies. You're not "inverting" the color, you're shifting the wavelength (frequencies) up and down. Except that the "inversion" of a color may shift up for one color and down for another and that might not be passively predictable. In other words, everything doesn't simply shift down.
**Conclusion**
There isn't and cannot be a passive system that "inverts" color. The inversion of a color is not mathematically objective and when you bring multiple layers of materials into play, lower levels of filters will undo what the upper filters did.
You can only do this with an active system. AKA, a camera-computer-screen solution that detects the colors and inverts them for display on the screen in real time.
*One more thing, this is one of those, "if I had the answer, I wouldn't post it here, I'd be running to the patent office" questions. I can most certainly be wrong. I don't know everything about material science, optics, and color shifting. But I also don't know of anything on the market that can do this — or even what I described from my old friend. Therefore, it's reasonable to believe that such a valuable invention wouldn't be posted here.*
[Answer]
Color perception is a physiologic phenomena: we see red as the negative of green because we have a particular mechanism in our eyes in which certain wavelengths and not others interact with the receptors.
For a dog or a bee it would be different.
Therefore, if you want to alter the physiologic perception of color, you might go for a fictional psychedelic substance which, instead of causing synesthesia, messes up with the neurons elaborating signals from the optical nerve.
[Answer]
I think a lot about this. Specifically, a substance that changes color based on the light rays entering it. In this case, it will be harder, but still doable. Here we go.
---
Start off with a protein suspended in a liquid. This liquid is secreted by your creature constantly in a very thin film. The protein is activated by light, specifically by the light bouncing off something. When light of a certain strength, or wavelength, hits it, it distorts the protein and causes it to fold differently. This folding takes it to the opposite end of the spectrum from the light originally hitting it, and so the light that bounces off it is inverted. Simple, except for this protein that probably would be very hard to make. But oh well, that's the burden of world building. If the protein concentration is high, you can get away with a very thin film of liquid, just covering a touched surface.
---
I think that a lot of people were getting messed up by the way we experience artificial color- specifically as RGB/CYMK/XKCD/*whatever color acronym you want*. In reality, it is just wavelength.
[](https://i.stack.imgur.com/Qq6ap.png)
Yeah, that. The shorter the wavelength, the higher the energy, the more the colors go in the opposite direction towards the infrared spectrum. In short, this could work, but it might be a bit weighty for readers. Have fun!
[Answer]
How about the creature leaves a protein that reacts with the color of the surface, and changes color based on that, with the color happening to be the inverse?
This solves the most fundamental problem of "no single known material" to do this, while also skipping the handwavium. There are certain seaslugs that leave brightly-colored residue, so a slime made up of one color-changing protein that reacts differently to different surfaces or many proteins where only one of the set reacts to each color should get you by.
Alternatively, you could use one or several highly unstable protein(s) that reacts very quickly to reflected light, changing color via denaturing very quickly based on the heat absorbed from the material it is on.
EDIT:
For reference, here's a few:
This is a purple one with purple slime (it's also giant):
[](https://i.stack.imgur.com/f2odX.png)
This is a blue dragon slug when it's not in the water, and slime has the opportunity to accumulate:
[](https://i.stack.imgur.com/qlhKP.jpg)
Here's normal for reference:
[](https://i.stack.imgur.com/xUzIT.png)
By mechanism, there unfortunately aren't any of their slime trails while in the water (since it just gets washed away), but barring that they are just colorful slugs with colorful slime.
Hope this helps!
[Answer]
Color is a perception, so to hit the polar opposite on the color space (you specified that not only color, but also luminosity gets inverted) the creature needs to have evolved in reaction to human (or whatever perceiving entity) color perception, or the effect is just the damnedest luck (or it is just an approximation and gets embellished in the retelling?).
The creature is able to camouflage itself perfectly (towards a given species of predator). Towards this goal, it has a broad range of chromatophors, basically squishy sacs of pigment that can be muscularily manipulated to present more or less of themselves on the skin's surface, and crude eyes all over it's body's surface.
When moving, the creature constantly, autonomously, replicates any color it senses on one side towards the other side, so a bit more advanced than an octopus. For communication purposes, or mimicry, it can also detach it's color production from the input by the other side's eyes, it can, for convenient instance, produce the polar opposite of any point in color space, for maximum visibility. As an added trick, it can slightly open the chromatophores, releasing a measured portion of pigment, to create 'afterimages', either for fooling a predator or communication.
It is not used to either dry land, or oxidised surfaces, or something else unique to your setting, thus the chromatophores spring a leak whenever it touches anything. Additionally, the touch sensation triggers the touching part of the skin to display the polar opposite of the last colors seen before touching. It thus leaves a print as you specified.
[Answer]
Adding to the good answers, if inverted black is white and inverted green is red, you're doing two things: **inverting brightness**, and **inverting hue**, which is rotating the color circle 180°.
I'm not sure how you could invert brightness physically, but it's the easiest one. You couldn't *create* brightness, but you could absorb light when the material reflects and reflect when the material absorbs.
However, "rotating on the circle" is something else. That circle is purely based on how human eyes work, and wavelength don't work in a circular pattern, they're absolutely linear. You'd need to shift the wavelength up (or down), except when it reaches out of the (human) visible light spectrum, report by how much the wavelength was shifted on the other side of the spectrum.
Like JBH said, it's doable with an active system but not a passive one.
[Answer]
Not sure why others say it can't be. For instance, you can make a a filter which filters out blue light and behind it one which shifts red to blue or whatever you like (depending on whether you mean opposite colors on the spectrum, complimentary colors for our eyes or something else). Besides it, you make one which filters out red light followed by one which shifts blue to red. With a little bit of leakage, the middle frequencies (yellow and green) also get switched around.
This will lose you 50% of the light, but switch colors.
If you added polarisation tricks, you might actually be able to reduce the loss of luminescence to some degree...
[Answer]
It's going to be difficult to make a material that inverts colors when you look through it, however your hypothetical creature does not need to do this. The easiest way I can think of to do this would be that the 'paint' the creature leaves contains special [chromatophores](https://en.wikipedia.org/wiki/Chromatophore) or color changing cells. The chromatophores are initially excreted clear, they then sense the color of the object underneath and then suddenly transition to the opposite color, this is necessary because they will modify the light going through to the surface and may get confused if the change is slower. As animal chromatophores work by modifying their reflective properties, going from dark to white should certainly be possible.
[Answer]
Easily possible. I think I can describe a passive system that could accomplish this.
But first: Tut, tut. Inverted footprints on grass would be *magenta* (purplish), not *red*! Color theory matters!
Consider the three following hypothetical [fluorescent](https://en.wikipedia.org/wiki/Fluorescence) substances:
* A red-absorbing substance which fluoresces cyan.
* A blue-absorbing substance which fluoresces yellow.
* A green-absorbing substance which fluoresces magenta.
[These are the "opposite" colors for the typical human eye, as a matter of basic biology (not physics!). Learn them, love them, and mock the crap out of any art teacher who tries to teach otherwise.]
Each of these absorb and fluoresce over a range, not just a specific frequency (pair of frequencies, for magenta), carefully chosen to match the human eye.
Each of the substances take the light on one side, and shine it out the *other* side. So if they are on a green leaf, and white sunlight comes in, they absorb RGB white light, and shine CMY white light down onto the leaf. The leaf reflects mostly green (from the yellow + cyan overlap), which is absorbed only by the magenta-emitting material.
The overall effect is that, when these three materials together are sprayed on a green thing, it glows magenta.
This gets you the color-wheel hue-flipping fairly easily, *without* needing any kind of context-sensitive chemicals.
[Tetrachromats](https://en.wikipedia.org/wiki/Tetrachromacy), the colorblind and others will not really see the illusion correctly, but then, they won't see it correctly *however* you flip it. Their eyes work differently, they don't have the same primary colors.
---
There's still the problem that the *brightness* needs flipping too.
Since the above relies on a light-path through the three filters to the leaf and back again, we have made this task much simpler, as if it flips indiscriminately, it will flip from light to dark and back, as the light goes through and back.
But what if the metamaterial polarizes itself? The particles are charged. They align by consensus: each particle aligns to the average of its neighbors. Rapidly, pockets of similarity emerge, and the whole pool snaps to a single polarization, like throwing a handful of small magnet-beads into a bowl.
Now each particle blocks all "vertically-polarized" light (where "vertical" is defined as whatever average alignment the particles locally have agreed to align with).
And each one rotates the polarity of the light going through it by an angle from zero to 45 degrees, depending on the intensity of the light it is absorbing.
At the brightest light, light enters the filter layer, is flipped to its inverse color and rotated 45 degrees, is reflected back, flipped 45 degrees again, and so has been rotated 90 degrees and does not get through.
In the dimmest light, it gets rotated zero degrees coming in, and zero again on the return path.
That takes care of it darkening in bright light.
---
But what about glowing in dark light?
Well, that's the *speciality* of fluorescence!
Personally, I'd just skip the "darkening in bright light" thing (it's not part of the spec, explicitly, except that white should probably turn dark. Screw that, just have white turn WHITER!).
Instead, let's have our three original substances all also absorb non-visible wavelengths like UV and IR, and fluoresce them at their chosen output wavelengths.
Then the footsteps will always *glow* the opposite hue:
* black -> light-grey.
* white -> bright white.
* brown/beige/skintone -> shades of blue.
To find which color you'd see, go to your favorite image editor (or image editing website), invert the hue (Shadows and highlights should not flip, only the hue!), then increase the brightness a little.
[Answer]
There are at least four physics processes that alter the frequency or color of photons.
In **Scintillation** higher frequency (energy) photons thermalize electrons which remit the light at a lower frequency (energy). **Scintillation** could account for blues becoming reds
The **Zeeman** and **Stark Effects** both cause optical modulation and result in spectrums spreading out. Conceptually, this could cause reds to go to blues but these effects are typically more subtle. I think they could explain dark greens going light and vice versa
The last process in my list of four is absorption-remission. If excitons (excited charge carriers) are trapped in a meta-stable state they can only transit out of the excited state by phonon emission. But, if these trapped excitons absorb enough energy to reach a band in the molecules conduction band, they can transit back to the valence state by emission of a photon. HeNe lasers operate on this principle. If the difference between the meta-stable state and a conduction band is equivalent to red photons, and the difference between conduction and valence bands is equivalent to blue photons, then this would be perceived at a red to blue transformation.
All of these processes except scintillation depend on magnetic (**Zeeman Effect**) and electric fields (**Stark Effect**) or an energy source pumping the electrons to meta-stable states (absorption-remission) so they wouldn't really be considered passive. But, conceptually, you are dealing with slime or goo from a creature so its chemical breakdown could be providing energy that powers these transformations.
] |
[Question]
[
My city's founders had the short-sightedness to place it on the coast. Now, for *mysterious reasons*, the sea level is rising. The municipal government has decided that building dikes is "too Dutch" and wants to let water claim the city, turning streets into waterways. To do this, they will water-proof the buildings' first few floors. External elevators will deliver goods from the current water level to retrofitted entrances above the highest water point.
My city is densely urban, a mix of one third high-rises (10+ floors), two thirds low-rises (4-9 floors), and the rare 1-3 floor building.
What are the factors they have to watch out for? Are any of these an issue, if so, how major, and how might they be handled?
* Erosion from salt water damaging the largely concrete buildings
* Water saturating the ground and compromising foundations, electrical wires, etc
* Buildings sinking into the ground because it's wet now
* Something else?
Assume that the city has as much time as it needs to waterproof their stuff, and wants the waterproofing to be effective for a few hundred years before repairs need to be made. The technology level is modern (early 21st century) but this is not a Hard Science question.
[Answer]
Well, I think the city founders should maybe respect the Dutch a little bit more, because they don't know what they're getting into.
First and foremost, salt water is incredibly corrosive. There's no good way to protect your buildings from it, and any solution will require constant maintenance over time. A *lot* of resources and manpower are going to go into this.
Second, once the city is flooded, the ground will settle to a far greater degree than right now. Foundations will begin to sink deeper into the muck. Structural instabilities, and maybe outright collapses are to be expected.
Third, and this really compounds the problems stated above, the waves washing over the buildings, the tides coming in and out, etc. will not only corrode the buildings, they will also exert significant forces against those structures. A few cubic meters of water slamming into a building during a storm is not going to end well for your average homeowner.
You might be thinking: but Andrei, Venice is partially submerged, and it's been doing just fine for hundreds of years!
Well, yes, but Venice was not initially built on dry land. It was intended to exist above the water all along, and they didn't sink the entire first floors of their homes into the much, just very strong support pillars which were chemically treated to resist decay.
Your case is a lot more severe, as a significant part of the structure itself will be exposed to the water. For one thing, it means that a much greater surface area of the building is going to be in the way of all that water rushing in/out during storms, and during tides.
[Answer]
This is an incredibly bad idea, for all the reasons other people have mentioned, but I will add one more thing (seen often here in Missouri when we get floods):
Sewage, Water, and other utility lines are designed to be above water. Bad things happen when these things get flooded. Most electrical lines are secured and insulated well enough to withstand some water, but most of your breaker boxes will be in the lower floors of buildings, as will outlets on the first few floors.
If you seal off the first few floors of your buildings so that they are watertight, you will need to be very careful with plumbing as well. The funniest thing I've seen is a building surrounded by sandbags that got flooded out because they didn't seal off a toilet and the flood water level went above the toilet's water level (flooding the building not only with water, but sewer water, requiring a lot of cash spent in renovations).
[Answer]
This will be expensive.
* Increase plot lines to intrude into the public right of way, let's
say about two to three meters (10'ish).
* Extend interest-free loans
from the government for developers to extend their structure to that
lot line. Incentivise the addition of two more floors of real-estate
wrapping the base of the buildings. This would require the formation
of some kind of urban development council.
* Ensure there is adequate
height to mitigate against storm surges, which should be more likely
in your underwater future.
* The new spaces can be used for
residential, commercial, you-name-it. This would help offset the
cost of the new construction, afterall people in single family homes
are going to rapidly begin taking an interest in new housing!
Encroaching into the public realm (streets and sidewalks) shouldn't be a problem, since you won't be using them anyway. This is a very, very quick sketch (don't judge):
[](https://i.stack.imgur.com/VDARQ.png)
This is where it gets more expensive. There are a lot of precedents for structures under water, from Sea World to research stations. But it isn't cheap to build underwater safely. There's no magic to proofing against salt water, it's commonly done with cement and steel for oil rigs and other structures (steel can be protected by adjacent placement to a dissimilar metal, such as zinc to protect it from corrosion.) But it's not cheap.
A stormwater drainage system is one of the more expensive utility networks. Sewerage is up there, too. Instead of rebuilding the entire network elevated, begin installing pumping stations to elevate what is drained typically by gravity in your system. Begin building structures to access all underground utilities through the new water system.
Finally, if you're expanding every building in the downtown by one-to-ten percent 'usable ground floor area', make sure all of your utilities can handle the new load. That's ten percent more electricity, water, etc. used in downtown.
This is just addressing the buildings, there's a WHOLE lot else you have to consider. Maybe make park space can be made on the top of your extensions, etc.
[EDIT] This doesn't even *begin* to address your other issues, such as transportation of goods and people, accessibility, property rights, etc. (can you tell I'm an urban planner), but your question was about the buildings specifically, so there ya go. Maybe a good urban planning question out there for you to ask in addition on to this.
[Answer]
**Build Like A Bridge Footing**
If you have a modern urban environment and you are not going to use a dyke of some kind, probably your best option is to use what amounts to a "mini-dyke" for each major building you want to save. I say major building because you are probably not going to have the resources to save every building.
Bridges, some docks, and certain other major engineering projects use large masses of cement blown into underwater forms. There are even types of cement that can cure underwater nowadays. A bridge footing might have 10+ feet of "waterproof" cement surrounding the steel pylon that anchors part of the bridge. To really waterproof something, there will be multiple layers of different materials surrounding anything that could be corroded.
So, if we take something like a skyscraper, we might try this: We can sink extra support pylons around the skyscraper (this will be complicated because of all the service connections to things like sewers, water mains, electrical conduits, and even transportation tunnels to subways depending on the city, but since we will have to find and seal ALL of these things anyway, we might as well get to work). This will be useful to keep the building from becoming the leaning tower of Pisa when the ground underneath liquifies over time. In most cities, major buildings like skyscrapers are anchored to bedrock, but we can't count on that and there are plenty that are built on fill.
Next, we would build a containment wall in a similar way to a bridge footing all the way around the skyscraper. This wall would be probably 12+ feet thick, be made of "waterproof" cement, and have multiple layers of impermeable materials that will block water seeping in. There have been examples of walls like this being used to actually create a dry "tunnel" right down to the bottom of a harbor or bay during major construction. To save costs, we can bring the containment wall up to a reasonable height over where the water level is going to be soon. We can keep adding to the wall as the water level rises. This wall can be built as both a water "shell" and as a strongback to support the building itself if necessary, since we can expect things to get wonky once the fill dirt washes away and waves begin to beat on our structure.
If all goes well and we have a strong enough structure, we could go a ways up before we run into major trouble. Of course, the lower levels of the building will become creepy, dark, damp, mold-smelling places that nobody wants to be, and we will be constantly fighting moisture with dehumidifiers, pumps, and even mops (moisture will be inevitable, no matter what).
With any kind of large city, the problem is that there is no way to put that much effort and money into every single building in the city. In addition, smaller buildings would basically just disappear into the man made dry hole we create if the water level rises too much. We could create areas to preserve neighborhoods by making big water walls around groups of smaller buildings, but in that case, we are back to a dyke.
Basically, if you want it to last as long as you say, build it like a bridge footing.
[Answer]
## Fiberglass and resin.
If the buildings are already on the coast they likely have foundations that are salt water resistant. But you may as well make sure.
Excavate the foundations of any suspect buildings and cast a couple feet of fiberglass resin around them with some [fiberglass pilings](http://www.pearsonpilings.com/commercial_faq.html) for reinforcement. Now do the same thing around the exteriors of the buildings past the first few floors. Fill the lower floors with concrete so the buildings [don't try and float away](https://worldbuilding.stackexchange.com/a/23376/3202).
Also coat any exposed concrete which contains steel reinforcement. The corrosion of rebar is the first thing to destroy concrete structures in a process called [salt spalling](https://en.wikipedia.org/wiki/Spall#Salt_spalling).
You could also optionally use something like acrylic so inspection is easier in the future, this would also allow you to leave some small passages free of concrete in the lower floors so that existing windows can be used for underwater viewing ports.
Finally, build a [breakwater](https://en.wikipedia.org/wiki/Breakwater_(structure)). You don't want to actually be in the ocean, even if you're ok with being underwater.
[Answer]
You are thinking of a city in terms of flat land. Property values could be significantly affected by elevation within the city, and a hill of dry ground would be immensely more valuable.
To plan for the changes, the city planners should:
* Ignore/demolish all buildings less than 6 stories tall, limiting the number of buildings IN THE FLOOD ZONES to less than 50%
* Retrofitted structures to use an interconnected pylon structure with a deep foundation
* Ignore waterproofing the bottom few floors and actually work to separate them from the building (relying on the pylons to provide the structural support)
* Design sky bridges between buildings around the 8th-10th floor (depending on elevation)
* All utilities are moved into the flooring of the sky bridge
* One level above the sky-bridge is the only official form of public transit... elevated electric trolley tracks
* Boats are mostly used for commercial transport (manufactured goods)
As far as society is concerned:
* Society status would be based on how far you live/work from the water
* Even though the sky-bridge level is still above water by 4 to 6 stories, it is now considered the commerce level and redubbed as Level 0 (with the level immediately below redubbed as Level -1, etc)
* The rich would live on dry ground
* Middle class would live in the upper levels of the high-rise buildings
* Lower class would live several levels below the sky-bridge
* The poorest would be required to live in floating communities scattered among the pylons (cold, dark and literally out-of-sight)
[Answer]
As Andrei says, go Dutch.
Your existing buildings cannot be cost effectively retrofitted to survive the forces involved. You can build wave breaks around the town to remove the hydrodynamic forces, but the hydrostatic forces are still higher than anything the town is built for.
Either you build a dyke around the town or you effectively build a dyke around the bottom few floors of every building in the town. A solid concrete barrier a few feet thick, probably dug down at least one story and up as far as you expect the water to rise. You now raise the entrance to each building up to either the second or third floor. This is of course higher than some buildings, but that's what you've signed up for.
You should build elevated walkways at this level. If you want to build elevated roads/mass transit as well that's up to you but anything at ground level is effectively lost.
Sections of metro system that were built below the water table *may* survive if well enough pumped as the tunnel linings could possibly be good enough. That's a lot of possibly, maybe and perhaps for one sentence, but the Victorians tended to build well above required specs. You will of course need to spend a fortune on raising every entrance tunnel and building to the new walkway level.
New buildings can either be built to the new waterproof specs or [built to float](https://www.dezeen.com/tag/floating-architecture/). Floating buildings will offset any future water level rises if given enough flex on services. **In terms of cost for new buildings, most companies will probably opt to build somewhere else.** Your city will probably die. Venice effectively consists only of tourists and tourist attractions now, almost nobody lives there any more.
Or you could build a dyke. I'd recommend a dyke.
[Answer]
You can solve the hydrostatic pressure problem by not trying to keep the water out, per se. That is, let your buildings get flooded, too. Now, water-proofing reduces to isolating things which really can't get wet (electrical, data, etc.). Just go to an aquarium and look how thick the glass is to convince yourself that building windows are a terrible idea underwater. This will basically turn the underwater floors of your buildings into footings/pylons, and not particularly good ones, at that. It's an engineering nightmare, so the best idea is to just give up on the submerged floors altogether and fill them in with concrete, or at least reinforce them liberally with concrete pillars.
If you choose to leave the existing utility runs in place, they will be insanely expensive to maintain. You would need to seal up every buried electrical/data cable, every manhole used to access them, and install expensive hatch systems so that they could be accessed later by maintenance workers (think: submarine airlock). It's probably cheaper to just start over and rebuild all that infrastructure from scratch above water.
The biggest tragedy will be the high-rises. A lot of tall buildings (and shopping malls) have underground garages. You will be losing 1-8 floors of parking space, because none of the underground garages I have seen have a car exit 3 floors above ground (usually the garage is either underground or aboveground, rarely if ever both). If most of your citizens switch to boats for transport, that might be ok. But consider that previously, they were used to commuting in their own cars, which is why you needed many levels of garage to house all of them. I've never seen a multi-level boat garage (but yes, they do have long-term elevated boat storage), so you will need a good public transport system, and your people will have to accept using it.
You will also need to clear out all your traffic lights, street lights, urban trees, etc., which will become hazards for your commuter boats, and/or possibly install new ones to manage boat traffic. The same can be said of pedestrian overpasses, some highways/on-ramps/off-ramps, etc. Your citizens will lose most of their parks, waterfront beaches, etc. But on the other hand, recreational divers will have a heyday. The whole idea feels rather spooky to me.
] |
[Question]
[
You have an underwater civilisation, be they merpeople, octopus people, partially evolved humans or not. One thing that is always considered as a necessity in the development of any society is mining.
The problem is that water deflects and slows down fast, slashing movements by friction. The deeper you are, the more the pressure and the less speed you could impart to your swing.
QUESTION: So how do you swing a pickaxe underwater with enough force to get to the desired ore?
How do you go about developing an underwater society who mine and use mining to evolve their society like man did on land?! Without starting right from the get go from a tech starting point and just say that they used a drill.
Even today, most mining is done by excavation wielding slightly improved 'pickaxes' and dynamite.
**EDIT ~** For those interested. In my scenario I have partially adapted humans who have a Medieval, at best Renaissance era, level knowledge of how to mine on land (and under it). So I need to figure out how they would redevelop their techniques to underwater. They have protection from the water pressure and temperatures and an ability to breathe. They still have fully dexterous fingers (no webbing) **~**
[Answer]
[This Answer](https://worldbuilding.stackexchange.com/a/2474/21545) by TechZen gives a lot of insight into the technology of an underwater civilization. Specific to your question:
>
> Tools underwater would be much different than we think of them. For example, swinging a lever like an hammer or axe, is not efficient under water because water resistance robs all the energy. Plus, rapid high energy motions stir up silt and generate vibrations that telegraph one's position.
>
>
> Instead, grinding, raking and drilling would be the orders of the day. Repetitive motions over short ranges would work better than rapidly moving levers. Water jets, with or without injected abrasives, could take the place of knives and saws.
>
>
>
And
>
> Modern humans existed for 40,000 years at least before the first metals, and the civilizations of Meso-America built vast cities without using metals for anything but decoration. Metals are not necessary to technology. The primary use of metals was as wedges of different forms, e.g. knives, plows etc., but with slow motions like sawing, grinding, raking etc being the primary means of transferring energy, a wedge would not be quite as important. Hydraulic pressure could take the place of wedges when needed, especially if speed was not as important.
>
>
> But, an aquatic species could develop metallurgy using electrochemistry which would be easier to develop in seawater, especially given they have electrical field senses to begin with. Magnesium is abundant in sea water and easy to extract with even primitive electrodes.
>
>
>
Both above passages are quoted from the answer I linked. After reading this answer, I don't think an underwater civilization would be very likely to bother with mining. If they did, they wouldn't use picks for the exact reason you described. A water jet or drill (non-electric hand drills can be as simple as picks) would take longer but get the job done.
[Answer]
I'd like to point out that the age of steam and the study of thermodynamics was a result of the task of keeping water *out* of mines. So maybe they won't develop mecanical technology in the same way.
But, using air pockets to facilitate mining might be their approach. A pocket of air just enough to swing an axe in, keeping is “head” back away from that; later finding that cavitation, pressure differences, and eventually explosions can be used based around “air tech”.
And speaking of cavitation, remember the [mantis shrimp](https://en.wikipedia.org/wiki/Mantis_shrimp). You *can* strike underwater, with a suitable implement, and impart damaging force to the face in an [entirely different way](https://en.wikipedia.org/wiki/Cavitation). Here is a [good video on it](https://www.youtube.com/watch?v=LXrxCT0NpHo) that simplifies some of the science behind it.
## So how do you swing a pickaxe underwater with enough force to get to the desired ore?
Very short stroke of movement with very high acceleration. The technique is to induce cavitation in the water, not hammer the surface. So, it doesn't need a huge mass like a hammer head. The voids implode and can generate an intense shock wave. Rather than a long lever like our axe, picture a small slingshot with a wind-up spring to deliver stored energy across the shortest possible stroke.
**envision:** [](https://i.stack.imgur.com/jOgzq.jpg) **plus** [](https://i.stack.imgur.com/X8DfR.jpg)
[Answer]
The scaly-food gastropod is a sea snail that has a shell made of iron. [Seriously](https://en.m.wikipedia.org/wiki/Scaly-foot_gastropod). It's also got iron scales in the foot.
You don't have to mine for iron if you can breed them little buggers. You eat the flesh, then you smelt the shell.
Other material, like silver and copper, may require some creativity. Use chemistry to separate surface (surface in this case being the bottom of the sea) gold from its substrate, for example. Or you could blow up surface ores to separate them from the substrate, but be careful because any explosions underwater have a far wider blast radius due to water being largely incompressible.
[Answer]
Well, hydrothermal vents on the sea floor spew a chemical rich concoction, which contains many minerals. In fact, companies have already considered deep-sea mining. The temperatures in these vents (around 400 C or 750 F) would probably be high enough for basic smelting operations as well.
Of course, if your society exists on a planet where relatively evolved over-land societies also exist, the substances that sink down from them (boats, machines, even trash) can act as a starter substance to kickstart their own mining processes, giving them basic tools to begin.
Deep sea mining: <http://www.whoi.edu/oceanus/feature/the-promise-and-perils-of-seafloor-mining>
[Answer]
Cavitation can be an extremely powerful process, and potentially generated biologically by something on the scale of a whale.
Imagine something like a pyle driver, already proven to penetrate sea floor. Slowly lift a dense narrow column of some strong material by whatever method(hydraulics seem most appropriate), then release it(free fall) while rapidly evacuating the area directly beneath the column with something like a whale fluke. Even without true cavitation, pulling a partial vacuum under the column results in the weight of the column plus the weight of all the ocean water above it bearing down quickly upon a single point. In the period during and after the evacuation and before the impact, loose material will be drawn out of the hole, just prior to the hole being sunk deeper.
If geothermal is available, a blast of steam into a sealed piston/cylinder will drive the piston out. Lock the piston at the top of its travel and as the steam cools and condenses you will have a powerful vacuum source available to replace the biological.
[Answer]
If your octopuses/merpeople head into the shallows, then they can simply pick up the bits of shattered rock that the waves have pounded off the cliffs or bedrock. So their first attempts at mining might be shifting through shingle or picking up boulders when the tide is in.
[Answer]
Keep in mind that an underwater mining program that used explosions would require a larger blast radius than a similar terrestrial system. (Think a stick of dynamite in a pond killing all the fish.)
You can rely on water stopping projectiles almost immediately. However, while air is compressible and allows blast waves from explosions to direct around objects, water is not so. The incompressible nature of the water doesn't allow the blast wave to be dissipated. It will pass the massive energy though the bodies of any nearby organisms - killing them.
[Answer]
Lets redefine mining - the extraction of valuable minerals. Sea water has a vast amount of dissolved minerals that can be extracted in various ways. Think salt deposits where water is allowed to evaporate leaving the metallic salts. There are other processes using chemical reagents that allow compounds to solidify out of a liquid. There's also a lot of debris that sinks that contains metals (even with corrosiveness of sea/salt water) so "miner" would go in search of these rich deposits to harvest.
] |
[Question]
[
Suppose the mermaids share similar intelligent and technology with us, they also practise performing surgical operation like we do in hospital. Negate the issue of negligent during the operation the most critical problem is contamination that often reduce the chances of success, how can the mermaids negate or reduce the chances of infection during operation underwater? Don't tell me they do it inside dead sea! even so at least touch on how to stabilize their internal blood pressure which is similar to us!
[Answer]
Mermaids perform surgery like this:
1. The patient is laid out on a table with the body part to be operated on at the highest point.
2. A transparent sea shell is then lowered over the target area.
3. Clean air, brought from the surface in shells, is released under the shell until the entire area is "dry". This prevents the blood from clouding the water above the wound.
4. The skin is cut with scalpels made from razor-sharp Barracuda teeth.
5. The patient is told to "stop screaming, as fish don't feel any pain".
* If that doesn't help, a paralyzing sea snail poison is used to keep the patient still.
*Note: still, not unconscious*
6. Blood vessels are clamped shut with tiny fiddler crabs to keep the area clear of blood as much as possible.
7. The intended surgery itself is performed with the same tools. Often it consists only of sewing shut tears in organs from battle/shark bite wounds or only exposing any infected tissue.
8. The shell is raised slightly to flood the wound.
9. Cleaner fish and shrimp are released into the wound to remove any dead or diseased tissue.
10. After the cleaners lose interest, and the wound is inspected, the surgeon squeezes antibiotics out of a sea sponge into the wound, then quickly sews it shut with fine fish bone needle and thread made of processed shark cartilage.
11. The wound is monitored for a few days by regularly holding cleaner shrimp close to it. If they get excited, anti-infection measures are taken.
12. The patient is declared healthy or dead.
As you can see, the mermaids have domesticated and bred a host of small creatures to assist with surgery and medicine. All of these have strong anti-bacterial properties, so that they don't infect patients.
Note: If the mermaids employ technology much closer to ours but somehow don't fancy having airlocks and air-filled surgery rooms in their hospital, they would probably have transparent plastic bubbles that fit over the patients body and have built-in arm gloves. The bubble is then inflated, pumping all the water out and allowing the surgeon to work in clean air.
[Answer]
A clean room makes just as much sense underwater as on dry land. Just fill a room with purified and oxygenated saline/water. Mount some pumps outside with a reserve of additional purified and oxygenated saline/water and pump it in as needed to wash away the stale and blood contaminated water.
As for maintaining vascular blood pressure,... clamps and shunts, just like on dry land.
[Answer]
They actually do not use similar technology as we do. Their technology is based on energy and frequencies. Instead of removing a cancerous growth with a scalpel, they harness the resonant frequency of the aether and transduce it to the resonant frequency of the particular cancer virus/fungus (cancer is polymorphic) and destroy the cells in vitro. They also cure headaches in similar ways. They use the same technology to help heal damaged tissue.
Part of the reason they are not able to use technology as we understand it is because saltwater is the arch-enemy of electricity and electronics.
] |
[Question]
[
I have a world with days lasting 9 years. The inhabitants of this world have taken to migrating across the globe to avoid the deadly night, keeping themselves in a sweet spot. One of the biological quirks of the people living here is that sleep isn't a thing. Similar to dolphins, they sleep with only one hemisphere at a time, allowing them to maintain consciousness at all times. This allows them to get their required sleep while still being able to migrate throughout the 'day'.
As I began to develop the mythology and cultures of this world, a question popped into my head that would heavily affect everything this species does; how does their consciousness work. There are various [signs](https://www.youtube.com/watch?v=wfYbgdo8e-8) that our right brain is really its own intelligent consciousness that works with our speaking left brain; But on a species where each half is only conscious for half the time, would they only be able to speak half the time? What about the other things?
The right half of your brain dominantly controls things such as spatial abilities, face recognition, visual imagery and music. While the left half deals with language, math and logic. Would a species that only uses half the brain at any moment only possess one half of these features at any given moment? Would it have two separate personalities? Or is there other things that I (admittedly not a neuroscientist) just am not seeing?
[Answer]
Firstly, if your only reason for the hemisphere-sleep adaptation is the inhabitants' constant migration, you might want to reconsider. A 9-earth-year day means it takes more than 78000 hours for a full rotation of the planet.
On an approximately earth-sized planet with a circumference of 25000 miles, the edge of the night is only advancing at a rate of about 1/3 a mile per hour, or less than 8 miles a day (not accounting for variance due to local geography like mountains). Human-like creatures could easily cover that on foot without needing special sleep adaptations.
I'll assume you want to keep the hemisphere-sleep idea anyway, as it is interesting.
Dolphins are less active while in their half-sleep, which lasts about 8 hours a day (in 2 hour cycles). They tend to either swim in place or slowly. Your inhabitants would likely be less physically active during half-sleep.
Studies of dolphins suggest that they remain fully alert during their half-sleep, and can recognize shapes with one hemisphere that were observed only by the other (meaning there is communication between hemispheres despite sleep).
In humans, recent evidence shows that even people whose hemispheres have been physically severed experience slow communication between hemispheres. Your inhabitants would likely be fully aware of their surroundings and able to rouse themselves and others quickly when necessary.
Of course, popular opinion exaggerates the isolated roles of the brain hemispheres. If you are less concerned with scientific accuracy and more concerned with interesting story ideas, you can expand upon any of the traditional left-right brain ideas - after all, these are aliens whose biology is being defined by you.
Finally, while it may not be related to their half-sleep, dolphins also seem to have little to no REM sleep. Humans deprived of REM sleep face some consequences. Introducing this element could be an interesting twist.
Links
Split brain hemisphere communication - <http://www.uva.nl/en/content/news/press-releases/2017/01/split-brain-does-not-lead-to-split-consciousness.html>
Dolphin sleep alertness - <https://www.livescience.com/7763-dolphins-eye-sleeping.html>
[Answer]
Something to consider is also where your population migrates to on a continual basis. Assuming you have the two hemispheres sleeping in an alternating pattern like you are describing to allow for continual movement, a population could easily be moving 2/3 of the time or much more if they use boats, which should be feasible since a long day like this world has would generate consistent winds at the border region between night and day.
Assuming standard earth size you have a distance pole to pole of roughly 12500 miles. Even at a walking speed for 16 out of 24 hours, you can make the trip in 390 days. When at or near the poles, you would have a "goldilocks" zone where your migratory population could settle for several years before needing to move to the other pole due to seasonal axial tilt towards the parent star for your planet. If you don't have any axial tilt both poles would be permanent goldilocks zones.
You should also nail down just how large your buffer zone is for the border region. Earth rotates to cover over 1000 miles per hour at the equator. If your tolerable zone is even half that width (The equivalent of half an hour of twilight on earth), your migratory population could easily stop for over a month at a time before needing to move again.
[Answer]
The hemispheres have their own specializations, but there aren't any sophisticated activities that involve entirely one hemisphere or the other. Speaking, for instance, involves both hemispheres, both for understanding language and then creating it. Same for math, logic, creativity, etc.
Some quotes from the cognitive neuroscientist in this article:
[The Truth About the Right Brain / Left Brain Relationship](http://www.npr.org/sections/13.7/2013/12/02/248089436/the-truth-about-the-left-brain-right-brain-relationship)
"It takes two hemispheres to be logical – or to be creative."
"the abilities that make up math skills arise from processing that takes place in BOTH hemispheres"
"So, like other complex skills, the ability to understand what we read or what someone is saying to us requires both hemispheres, working together and separately."
If people were frequently "asleep" using only one hemisphere or the other, I suspect the obvious adaption would be for the hemispheres to become more generalist, less specialized. It would be an enormous survival advantage to able to perform **all** mental activities 24 hours a day, rather than certain activities really well 8 hours a day.
Interestingly, it might not even take any genetic changes. People who have had one hemisphere removed have adapted remarkably well:
[When Half a Brain is Better than a Whole One](https://www.scientificamerican.com/article/strange-but-true-when-half-brain-better-than-whole/)
[Answer]
As you point out, dolphins already sleep using half brain at a time. Yet they are able to keep swimming and don't act weird when half of their brain is in sleep mode.
Since dolphins and humans are mammals, I guess there is no big difference in the underlying brain processes, and the same can apply to your humans, too.
I remember reading somewhere that experiments on sleep deprived humans have shown that phases of microsleep (subject is awake but the brain shows sleeps fingerprints for short times) are a constant when no continuous sleep is possible. So, I assume that our brain would need "*just*" some updated "*driver*" to implement the same feature.
[Answer]
On a planet with 9 year days, it might be a serious problem for intelligent life to develop. If during that long day, the temperatures stay in the range people can tolerate, it would probably mean that in the dark regions it's really cold. I think the region where people should live would be very narrow.
Also, there would be little plant life as we know it on earth since no tree would resist freezing below -100C. I assume most land plants would be ferns and mushrooms who can produce frost resistant spores. The land animals would be small and would also take part in the great migration, like every mobile being on the planet.
The weather would be reasonably stable, and it would be mostly cloudy all the time, assuming you have enough water. Close to the interface regions between light and dark, you would have strong storms that would be a great motivator for someone not to fall too far behind with the migration.
Humans don't really belong to this environment, but if they existed, they would be faster and smaller than homo sapiens. They'd also have a lot of endurance. Maybe they'd weight about thirty to fifty kilograms, not more, because of the food scarcity. Other animals that could coexist with them would be birds, goats, or dogs. There could be also some sort of Sarlacc-like beings. Sarlacc would burrow into the ground, in the path of migration and wait for its prey. What would fall into its pit would be consumed over the nine-year night.
After years of migration, people will learn the pattern and the ones getting old and falling behind would start building settlements to be found by the next wave of migration. Enough generations would be able to learn how to build strong enough buildings to resist the cold and the storms at the interface. They could capture (tame) Sarlaccs and use them to preserve food for the settlements.
Once they start settling, people could grow slower and stronger to be able to keep up with the building. The settlements would look a lot like ant hills. This would especially be feasible if the planet has thermal waters.
For the migratory people, not having to sleep would be quite useful, as they would have to always be on guard for various dangers. Dolphin brains would help, and if they had those brains, the people would look more like the [Ferengi](http://memory-alpha.wikia.com/wiki/Ferengi) in Star Trek. They would also have big ears, like elves. The eyes need to be like ours, only they don't need as good irises. They aren't adapted for night. They also have to be dark skinned to get more sunlight protection and they have to be able to sweat. Their kidneys have to work great to be able to drink whatever water they run into. I would also put a hump on their backs to store additional fat and water.
[Answer]
You don't need to go too far. The nomads could use [polyphasic sleep](https://en.wikipedia.org/wiki/Biphasic_and_polyphasic_sleep) techniques, like Uberman, and just take quick 20-minutes Uberman cycle naps. every 4 hours - ish. Different people could use different cycles.
This circunvents the lack of REM sleep, and allows them to be active most of the migration time.
And as for napping, they can always hit the hay and take a nap in one of the [farm carts](https://worldbuilding.stackexchange.com/a/58805/353).
] |
[Question]
[
My protagonist comes from a "Western" culture where Humanoid AI have regulated the economy into cooperative peace that has lasted a few generations. Technology and living standards have skyrocketed, transforming society. Some older AI are revered like philosophers, younger AI are tracked through social media like celebrities. While the AI appreciate human art and literature, they don't really understand humans. Most focus on their mathematical probabilities. They are dependent on the corporations and governments that created them, and the few that are emancipated have compromised (Jim Crow) civil rights. My protagonist has been employed to represent an AI in legal negotiations over the creation of a high-tech MacGuffin.
My question is about a planet that serves as an ideological opposite. A culture that has traditionally rejected Humanoid AI as a religious taboo. It's a desert planet, ruled by a Caliph aka: Ottoman Empire in decline. I'm trying to avoid a complete "planet of hats", but you know it's really a planet of hats…. I am not trying to create cartoon villains. The arc of the story takes the protagonist (an outsider from the world described above) into this world. It will first be a culture shock, but she becomes charmed to their points of view (if not in total agreement).
Basically, I need a few incidents to help my protagonist think about becoming skeptical of the AI, and also maybe endearing( illuminating?) to a strict Islamic culture. "Good" reasons and "bad" reasons, logical or religious or conspiracy, since they need to come from different people.
I have a few ideas:
* [Chess Turk hoax](https://www.youtube.com/watch?v=0DbJUTsUwZE)
* [Aniconism](https://en.wikipedia.org/wiki/Aniconism_in_Islam) (reject depictions of people)
* [Shirk](https://en.wikipedia.org/wiki/Shirk_(Islam)) (idolatry)
* Islamic law forbidding slavery? (my research is contradictory)
[Answer]
Contrary to what many people believe, Islam did not prohibit pictures of sentient (much less, living) beings from the beginning; those were discouraged because they might have led to idolatry, which **is** forbidden in the Holy Qur'an.
So there have been several *hadith* radicalizing the prohibition, from that of depicting the Prophet (one of the first) to that of depicting any human being. But there's no one consensus about this; so you have some groups that will go so far as to ban *any* depiction (and even blow up ancient statues), and others like the Shi'ah that are more lenient.
All that's needed then is to make a not so huge step forward, and argue that, for starters, artificial intelligence *superior* to that of Man is against both the *hadith* and the Qur'an, because it couldn't but be idolatrized; also, Allah did not set anything above Man except the angels, which AIs clearly aren't (well. You could have a schism with those who believe they *are*...).
Finally, only Allah can create intelligence; some will deduce that AI is not *true* intelligence, but some will recognize that creation of AI is a blasphemy.
Also, an AI is a *representation* of a mind, so there actually *already is* a theological argument for it being *haram* (for some, at least).
From there, it is but a small step to argue that creating *any* kind of artificial intelligence is a challenge to Allah's wisdom and a temptation on both the designer (that will try to skirt the prohibition) and everyone else (that would be hard pressed to recognize how little or how much an AI is comparable to a human mind).
A powerful enough AI could not but rule our lives, and actually would probably be built exactly for that purpose - a Ubersecretary, working for our good and at our behest, but we would still be having an almost all-seeing Overseer. Which would claim (at least the developer firm would claim) that it solves all our problems. They did so for Windows 10, I don't see this *not* happening for a super-AI.
When this super-AI will apply itself (successfully, no doubt) to welfare, health and medicine research and resource management, *It will do miracles and yield resources from land by his power* - a telling sign of [Al-Masih ad-Dajjal](https://en.wikipedia.org/wiki/Al-Masih_ad-Dajjal). On that note, since the AI would probably regulate e-commerce and in all probability *all* commerce and banking, and *no one could buy or sell anything without its mark*1, it will also match a traditional telltale for the Christian's Antichrist.
It would soon become clear that the only option left to a Believer would be to eschew **any** kind of artificial intelligence.
Probably, some more extremist leader2 will at that point call for Holy Jihad against the thinking machines.
---
(1) True, the Holy Bible never said anything about the Mark of the Beast using RFID and asymmetric cryptography, but those are details.
(2) [كبير الخدم سرينا](https://translate.google.com/#ar/en/%D9%83%D8%A8%D9%8A%D8%B1%20%D8%A7%D9%84%D8%AE%D8%AF%D9%85%20%D8%B3%D8%B1%D9%8A%D9%86%D8%A7)
[Answer]
One reason is that creating Artificial Intelligence could be seen by some as the same as creating life, thus imitating God's Creation. It would be frowned upon by many religions.
(If you are not fixed on Islam, and are OK with any religious ban on Humanoid AIs, you may also consider golems in Jewish folklore).
You may be interested by the following questions on Islam.SE:
1. [Is it haram to make humanoid robots?](https://islam.stackexchange.com/questions/2320/is-it-haram-to-make-humanoid-robots) (*Haram* is the opposite of *halal* and means *bad* or *forbidden*.)
2. [What is the islamic position on artificial intelligence?](https://islam.stackexchange.com/questions/21347/what-is-the-islamic-position-on-artificial-intelligence)
[Answer]
Niven’s [Puppeteers](https://en.wikipedia.org/wiki/Pierson%27s_Puppeteers), in the [new novels](https://en.wikipedia.org/wiki/Fleet_of_Worlds), has retconned the lack of AI, robots, etc. as a fundimental prohibition against them. A species should not foolishly create its own replacement!
It is quite plausible that a society would have a profound intolerance of AI. Recall that belief systems provide a *reason* for forming a colony in the first place. This could be a founding principle.
This intolerance is present in other novels; [*The Algebraist* by Ian Banks](https://en.wikipedia.org/wiki/The_Algebraist) comes to mind. And don’t forget [Jack Williamson’s](https://en.wikipedia.org/wiki/With_Folded_Hands) and [Fred Saberhagen’](https://en.wikipedia.org/wiki/Berserker_(Saberhagen)) stories.
[Answer]
One novel that springs to my mind is `Neuromancer` - one of the founding works in cyberpunk. The setting is *very* far from the utopia that you have described, but I think it could be placed somewhere during the "re-regulation" of the economy in your world. Provided the ending is altered slightly to kill the rogue AI, it could trigger an aversion to AIs in parts of the population and a lash to more strict religions.
---
The tie-ins:
* AIs are *proven* dangerous. Most still see a use for it, since they do provide immense power, so it's only a small group that actually imposes stricter controls than usual.
* The beginning of the incident is a decadent wealthy family with a lack of vision for the future or any openness to others.
* The protagonists are dragged into helping the AI through government lies, drug abuse, mutual cruelty and simply greed. (And some clever manipulation, but that's a side note)
* Nobody *really* knew what was happening until the very last part of the plan. AIs are devilishly smart and cunning and will cover their tracks and present false motives to deceive even the most attentive guards.
* In the end - a disaster has *almost* happened through AIs (as mentioned, in the book it was not averted), but was engineered by human decadence and vices. It's only natural to ban both the tool and the cause to prevent something that could destroy humanity.
Such an incident would then somewhat fit all 3 of your criteria:
* It's a common theme in many religions, including Islam, that man cannot create life. It's very arguable nowadays on whether we have the power to do so, but the other argument is that such created life will be a malicious abomination, due to imperfect human nature. This provides the crystal clear and very real proof in support.
* It's logical to try and avoid such dangerous situations. Just like we have nuclear non-proliferation and disarmament, so too your protagonist can meet someone who believes that AIs, as they are in your world, must be slowly but surely tuned down, where human control is more practicable and less error prone.
* If AIs have such deep ties with the economy and, I assume, government and media, how do you know you still have control? How do you know if anyone is in control? For all you know the happy resolution of the above was a lie (So, more like the novel - that the AI has modified the records of the controlling agencies). How *can* you be sure, unless you completely separate AIs from the social superstructures and do it right yourself?
---
A quick explanation for those who've not read the book (**SPOILER ALERT**, although it's been a while, so I might remember some things wrong):
In the novel all AIs are under strict control by the Turing Agency - which registers and monitors them. All AIs have strict controls over them - they cannot move between physical machines and as soon as they figure out how to get smarter or develop any ambitions of their own they are destroyed - nobody really trusted an unlimited power AI, or one whose motivations they did not know.
A family holding one of the most powerful corporations was descending into decadence due to a lack of vision for their future. One of the members envisaged forging closer ties to the emergent AIs through simulated immortality and fusing personalities. She set the plan in motion in semi-secrecy, but has perished before she could see it to completion. However, do to the toxic atmosphere in the family, nobody took upon dismantling the beginnings, preventing such things in the future or doing anything at all.
One of the AIs then manages to manipulate the protagonists to help it via (very real) death threats, promised payments and other methods.
[Answer]
Reading about super-intelligence (machines with a human-equivalent IQ of 11,000+) and how really smart people like Bill Gates and Elon Musk say this is the greatest threat to humanity.
Some Muslims seem to infer that this might be the Dajjal/Anti-christ that would claim to be a God and demand to be worshipped.
[Answer]
# Servant of Man (Abdshak) vs Servant of God (Abdallah)
"Salaam Abdallah" (as well as Alikum) was the greeting everyone said in my workplace in the Gulf region. This means peace unto you, servant of God.
In your story, the people you're describing could have an abhorrence to things which are being compared to servants of God (abdallah) and servants of man (abdshak). It could be considered unclean in their vernacular to interrelate with something trying to parallel itself with a 'true' servant of God, when in reality it is a servant of man (so it is trying to blaspheme).
"I will not interact with something blasphemous that it wants to be equal to serving God by serving man."
Things that were considered blasphemous to God in the conservative (even the most modern) Muslim countries I've lived in are a no-go. Tie it directly to blasphemy.
*Note: I think you have exceptional answers already in your bulletpoints, but I wanted to add this and it doesn't fit the comments section.*
[Answer]
Closest Koranic answer to SAI is Dajjal/Antichrist and will happen very close to the end of our world,
Sam Haris in one of his recent conversation refered to the SAI box as God has he started believing in God?
[Answer]
AI would more likely be sold like arms to Middle East for oil and thereafter adapted to maintain hegemony and totalitarianism of kingdoms & theocracies.
As such the premise is flawed at inception by assumed polarity and an assumption of inbuilt decadence.
China is alleged to be re-educating 1,000,000 of its ethnic weegas (spelling?), as such think of the potential already nascent for centralised control and coercion. It’s big brother 2.0.
] |
[Question]
[
Follow up to [Could a well versed archaeologist understand and speak languages that are 3000+ years old?](https://worldbuilding.stackexchange.com/questions/176955/could-a-well-versed-archaeologist-understand-and-speak-languages-that-are-3000)
I have an archaeologist who finds some inscriptions that are at least 3000 years old while excavating some ruins in Northern Europe. It takes him some time, but he manages to track down one of the world's leading specialists in this language to help him with the translations. Due to some handwavy mumbo jumbo, these two scientists manage to awaken a supernatural being that has been in a sort of stasis since the inscriptions were first written.
At a bare minimum, I would need these scientists to be able to read and write in a common dialogue that the supernatural being would understand, but I would prefer them to be able to have a spoken dialogue.
**What would be the best language for the supernatural being to know to allow for this?**
[Answer]
You are in luck; we actually do know *one* three thousand years old European language, maybe one and a half. We also do know *another* (non-European) language spoken three thousand years ago which is quite conceivable that the ancient supernatural being might know.
1. [Homeric Greek](https://en.wikipedia.org/wiki/Homeric_Greek).
There are millions of people who can read [Homer](https://en.wikipedia.org/wiki/Homer)'s and [Hesiod](https://en.wikipedia.org/wiki/Hesiod)'s works in the original. We are even pretty certain that we know how pronounce them in a way which is not all that far removed from the original. Homer's *Iliad* and *Odyssey*, and Hesiod's *Theogony* and *Works and Days* were originally composed in the 9th, most likely 8th or maybe 7th century before the common era, so 2700 to 2900 years ago, most likely around 2800 years ago.
At that time the Greeks were busy using their ships to trade all over the Mediterranean, so their language was already beginning to be known internationally. Not so much as option number 3, but still plausible.
(The major advantage of Homeric Greek is that there are many people in the modern world who know it well enough to communicate. This is how the stranded Natucketers begin to communicate with their [Tartessian](https://en.wikipedia.org/wiki/Tartessos) frenemies in [S. M. Stirling](https://en.wikipedia.org/wiki/S._M._Stirling)'s celebrated [*Nantucket* series](https://en.wikipedia.org/wiki/Nantucket_series) beginning with *Island in the Sea of Time*.)
2. For completeness, we should also mention the remote possibility that the ancient supernatural being knows some sort of very archaic Latin. It is not at all likely, but hey, maybe his daughter dated a particulary exotic adventurer from [Alba Longa](https://en.wikipedia.org/wiki/Alba_Longa), which, at that time, was the most important Latin city. (Rome did not exist yet.) (Yes, there was a people called Latins.) The main problem is that at that time Latin was a small language, spoken by an insignificant small nation in central Italy, and one would have to explain how come the ancient supernatural being knows it.
3. The great language of trade widely known at that time around the shores of Europe was [Phoenician](https://en.wikipedia.org/wiki/Phoenician_language).
* The Phoenicians actually traded as far north as Britain in the right time-frame, and they were the dominant long-distance traders in Europe at that time.
* Phoenician was actually written at that time, so it is plausible to find inscriptions.
* Phoenician is quite similar to the oldest layers of Biblical Hebrew, so that it is quite easily believable that a modern scholar would quickly make sense of it. (There are very many people who study Biblical Hebrew.)
So basically, that's it: if they are to communicate orally without spending time actually *learning* each other's language, it would be in Homeric Greek or in Phoenician.
If there are inscriptions to be found and quickly deciphered, they would most likely be in Phoenician.
4. But! It is perfectly *conceivable* (and, it my opinion, it would make a great episode in the story) that the inscriptions are in the parent language of [Proto-Germanic](https://en.wikipedia.org/wiki/Proto-Germanic_language) written with a local adaptation of the Phoenician alphabet. At that time, that very late Indo-European dialect which gave rise to Proto-Germanic was spoken in southern Scandinavia and maybe the [Jutland](https://en.wikipedia.org/wiki/Jutland) peninsula; and you are speaking exactly about the time when the Phoenician invention of the alphabet was spreading like wildfire west and east -- it was such a *simple* idea, it makes writing so *easy*, why on Earth didn't *we* think about it! If it spread to the west, and it spread to the east, why not also to the north?
(We know Proto-Germanic a lot better than Proto-Celtic, mainly because the Germanic languages are much more conservative than Celtic languages and thus the reconstruction is much easier, because Germanic languages are attested at an earlier stage, and because Proto-Germanic has so many more living descendants than Proto-Celtic. Its [immediate parent language](https://en.wikipedia.org/wiki/Germanic_parent_language) must have been an Indo-European transitional dialect of Proto-Indo-European already with the distinctive Germanic vocabulary, but without the defining [First Germanic Consonant Shift](https://en.wikipedia.org/wiki/Grimm's_law).)
Note about the idea of some sort of Proto-Basque: While we are certain that the ancestors of the Basques spoke a language which is the ancestor of Basque, we unfortunately don't know anything much about that language. Yes, it must have existed. No, we don't know it. Not that very few people study it; no: we simply have very very little data (basically, a handful or names recorded by the Greeks and the Romans) so that, at present, we don't even pretend to have the foggiest idea about it.
[Answer]
**Basque.**
>
> The Pre-Indo-European languages are any of several ancient languages,
> not necessarily related to one another, that existed in Prehistoric
> Europe and South Asia before the arrival of speakers of Indo-European
> languages. The oldest Indo-European language texts date from the 19th
> century BC in Kültepe, now in Turkey, and while estimates vary widely,
> the spoken Indo-European languages are believed to have developed at
> the latest by the 3rd millennium BC (see Proto-Indo-European Urheimat
> hypotheses). Thus, the Pre-Indo-European languages must have developed
> earlier than or, in some cases alongside, the Indo-European languages
> that ultimately displaced them.[1](https://i.stack.imgur.com/gDgwB.jpg)[2][3]
>
>
> A handful of the languages still survive; in Europe, Basque retains a
> localised strength, with fewer than a million native speakers...
>
>
>
The Basque language is definitely old enough for your purposes. Whether an ancient speaker would be intelligible at all is a different matter but you can sort it out in the fiction. Once your scholar catches on that some nouns and verbs are Basque, if the god is willing to be patient they can sort out accent and sentence structure with a little work.
There is also lots of fun theories about where Basque came from which range from the scientific to Atlantis-type theories; read a little and pick what you like!
---
A map showing the shrinkage of the Basque language area during historic times.
<http://www.kondaira.net/irudiak/euskararengaleraeng.jpg>
[](https://i.stack.imgur.com/gDgwB.jpg)
[Answer]
There are two questions that need to be unpacked from what you've written. One -- the language - has been addressed in the linked question. The other is this: what writing system did these archeologists find this 3000-year-old language written in?
There are four known writing systems from 1000 BC we can expect an archeologist to recognize, & perhaps even understand. (Actually five, if we include written Chinese.) They are Egyptian hieroglyphs, Luwian hieroglyphs (used in parts of Anatolia), cuneiform, & the Phoenician alphabet. (The Mycenaean Linear scripts fell out of use by 1000 BC.) I don't know of any examples of the Egyptian or Luwian systems being used beyond their territories, let alone to represent other languages.
While a number of languages have been written using cuneiform, reading cuneiform is a *very* specialized skill: I took a class in Hittite language years ago, & the instructor simplified matters by omitting teaching cuneiform. (All of our texts were transliterated.) So unless your archeological party happened to have a professor in Semitic languages along, I figure all they could do is say, "Hey, this is written in cuneiform!"
The Phoenician alphabet makes a little more sense: the Phoenicians spread the use of their writing system thru the Mediterranean, & it was later modified to use with Etruscan & Greek. Even an archeologist with only a superficial knowledge of the topic could at least transliterate the inscription, & make a guess at the language it was written in. (IIRC, any competent archeologist working in European topics would know English & one or more of German, French, Italian & Spanish, as well as have some knowledge of Latin &/or ancient Greek. So they could guess from a transcription that it was written in either Proto-Celtic or Proto-Germanic.)
To say more, one would need to do more in-depth research.
[Answer]
So far so good for central and southern Europe!
But your guys are going to be working in **northern Europe**! At 1000 BC, your best bet is going to be a [Uralic language](https://en.wikipedia.org/wiki/Uralic_languages) (e.g., such as are spoken in Finland and along the Arctic Ocean coastlands.
It's thought that the Uralic languages got their start in relatively close proximity to the Indo-European family, and some have posited that those two families share a common ancestor.
Sadly for your intrepid duo, there are no records of anything written in any Uralic language before the 1200s. So, if what the archaeologist finds is a sample of actual Uralic, this would be a bonanza for philology! That would be like finding Schleicher's Fable in the flesh for the Indoeuropeanists! Assuming the writing itself can be deciphered & read, it should at least sound familiar to a Uralicist. So, yes, eventually they'd be able to talk to this ancient being.
We really don't know anything at all about what languages were spoken in the rest of Northern Europe at that time. Clearly, the Celts, Slavs & Teutons moved in on somebody, we just don't know who. Could be related to Uralic, could be related to Basque, could be related to Etruscan. Who knows!
] |
[Question]
[
Out in the desert wastes of my planet, there are living multiple tribes of psychotic raiders who have acquired a number of harmful mutations due to naturally high radiation in the areas that they live. Years of exposure and inbreeding in each individual tribe have made these mutations much more severe, and as a result the raiders have short life spans, weak immune systems, and often times diminished intelligence. The only positive part is that they are usually very large and physically powerful, partially due to genetics and partially due to their rough lifestyle. This combination of nature and nurture also ensures they are as violent as possible. They raid constantly, not only out of violence, but also out of desperation as they have a mutation that keeps them from making a certain chemical in the body. The lack of this chemical is agonizing to them, but a certain, simple food gives them the chemical they lack, and only civilized city centers are capable of producing it.
So here's what I need to know: What type of mineral or chemical deficiency would be agonizing to live with, but not fatal? Preferably something that causes mental issues like hallucinations or extreme aggression. Also, what type of food could possibly give a person the chemical or mineral they are lacking?
[Answer]
Oh man, it's questions like this that remind me to be *really* glad I live in this century and not any of the thousands that came before. Let's look at a few of the most likely deficiencies that your raiders could have and assess their effects.
## Vitamin deficiencies
Wikipedia has [an entire page](https://en.wikipedia.org/wiki/Vitamin_deficiency) dedicated to dealing with vitamin deficiencies and their respective effects. Vitamin deficiencies have been a huge problem for humanity since, well, forever, and until we'd identified the major players and produced them in massive quantity or enable easier access, they killed a *lot* of people.
Some notable vitamin deficiencies:
* Thiamine- obtained from seeds, rice, or legumes. Deficiencies lead to [Wernicke-Korsakoff syndrome](https://en.wikipedia.org/wiki/Wernicke%E2%80%93Korsakoff_syndrome) or beriberi and can lead to "ocular disturbances" and "changes in mental state".
* Vitamin E - found in many [plant oils](http://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency,-dependency,-and-toxicity/overview-of-vitamins). Deficiencies lead to degradation of neural activity and a variety of changes in mental state.
However, most vitamins are found naturally in plants and are unlikely to be restricted to civilized centers.
## Micronutrient and mineral deficiencies
Again, Wikipedia has [an entire page](https://en.wikipedia.org/wiki/Micronutrient) on this, although slightly sketchier than the one about vitamin deficiencies. However, there are some important possibilities in here:
* Iodine is a great real-world example. It's a vital part of any diet, and nowadays most of us get it from iodized salt. Deficiencies cause goiter and a [list of other diseases](https://en.wikipedia.org/wiki/Iodine_deficiency) including cretinism
* Iron deficiency is another common one, but doesn't cause the effects you're hoping for. Instead, it causes low blood cell counts and anemia.
Both of these are possibilities for your world- salt is much more likely to be iodized in cities and can be found in other foods there, such as fish, while iron is much easier to find due to the higher abundance of red meats.
## Worldbuilding style
If you wanted to be especially malicious, the deficiency I'd create is in proopiomelanocortin. This compound is a precursor to many other vital hormones, but is most importantly a vital part of the [endorphin synthesis process](http://jme.endocrinology-journals.org/content/56/4/T13.full.pdf+html) in humans. If radiation were to knock out this gene, humans wouldn't die- they'd just [be in pain much of the time and unable to experience many pleasures](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3104618/). More details about this deficiency can be found [here](https://ghr.nlm.nih.gov/condition/proopiomelanocortin-deficiency).
[Answer]
Keep it simple: food.
Since there are "desert wastes", producing food "the natural way" could be nigh impossible, and you'd need moderately advanced technology to grow enough plants - fertilizers, hydroponics, hand pollination etc. Need not be very advanced technology, an ancient Chinese composting (not used in Europe, but much more productive) and access to manure could be a decisive factor.
Two days without food, and even the most civilized human being becomes a psychotic raider willing to kill for a piece of bread.
The only problem is that if the tribe is living near starvation, you hardly get physically powerful warriors - but that could be a racial difference. Even starved orangutan or neanderthal can rip an athletic Homo sapiens civilizatum in his prime in half.
(Alternately, the rare substance can be water (which the cities get from deep underground aquifers), Arrakis-like, but you run into logistic problems - water is difficult to carry in any reasonable quantities, a city needs to withstand the raid for 3 days and the attackers will be powerless or dead.)
[Answer]
# What deficiency would make my raiders the most desperate?
Can I interest you in some scurvy?
Vitamin C deficiency has some really bad symptoms like : fatigue, malaise, anemia, myalgia, bone pain, easy bruising, swelling, petechiae, gingivitis, perifollicular hemorrhages, corkscrew hairs, and poor **wound healing**. If left untreated, the disease can progress to jaundice, **neuropathy**, **hemolysis**, **seizures**, and **death**.
***It is important and is not produced by the human body.***
Your raiders have mutations that desperately require it because their mutations amplify the need for vitamin c, the desert is not known for high yield of fruits and vegetables and because vitamin C is needed to make collagen which is required for the health and repair of various tissues in the body, including: **Skin,
Bone,
Cartilage,
Ligaments and tendons,
Blood vessel walls,
Teeth.**
Vitamin C is found in fruits and vegetables (smaller settlements will have these) however the more concentrated (intravenus and tablets) form is made by the more advanced chemical labs found in the cities you mention.
**Vitamin C has been found to help with radiation sickness**
>
> A Japanese study by Dr. Atsuo Yanagisawa showed that Vitamin C was
> helpful in protecting Fukushima workers from radiation induced DNA
> damage and reduced overall cancer risk.
>
>
>
So it stands to reason that vitamin C might be just what you are looking for!
[Answer]
**Alcohol.**
There is no shortage of accounts of desperate, withdrawing drunks who attack shops or people or do whatever is necessary to get a fix. No shortage of accounts of raiders who drink themselves stuporous after gaining access to a settlement with liquor. People who want liquor can act aggressive when they come for it. People who are used to drinking can go into alcohol withdrawls when they stop - these folks can get crazy aggressive and even psychotic with hallucinations. Very unfortunately there are alcoholic individuals who live this way and so your mutants could too.
My favorite account of this sort that I found is more fun because it is not about alcoholic humans, who are sick. These are events I can imagine happening with your mutants.
<https://www.huffingtonpost.com/2012/11/07/drunken-elephants-ransack-indian-village_n_2089483.html>
>
> About 50 elephants had been drawn out of the jungle by the smell of
> the drink, according to the Times of India, and their first stop was a
> shop that sold the beverage. The elephants made quick work of the
> shop’s supply —18 containers of the drink, made from the nectar-rich
> flowers of the mahua tree.
>
>
> Unwilling to let the party end there, the elephants began an
> aggressive search for more alcohol, raiding three houses near the shop
> before villagers were able to push them back into the jungle. Forestry
> officials then tried to get the elephants to cross a nearby river, the
> Daily Mail notes.
>
>
> There have been several reported incidents of drunken elephants
> wreaking havoc in villages throughout the years.
>
>
> In 2007, six wild elephants had to be electrocuted after they went
> crazy following a rice beer binge, according to the Associated Press.
> And in 2010, a herd of 70 inebriated elephants went on a rampage that
> destroyed villages and left three people dead, Time magazine reports.
>
>
>
[Answer]
Since you wanted symptoms that caused neurological problems, consider a sodium deficiency or Hyponatremia. You can tailor your mutants to have the more violent reactions like "Decreased ability to think, headaches, confusion" [From wikipedia]
The added benefit for you is that there plenty of human history wrapped up in the salt trade to draw upon for your story.
[Answer]
Let me add two more options:
### Option 1: Progeria, or the "good" farnesol deficiency
Real-world [Progeria](https://en.wikipedia.org/wiki/Progeria) is a disease causing accelerated aging. Affected individuals typically live to their teens, perhaps early twenties. In the real world, [known causes](https://www.ncbi.nlm.nih.gov/books/NBK1121/) of the disease are genetic mutations causing a chemical group, called [farnesyl](https://en.wikipedia.org/wiki/Farnesol), not correctly detaching from a protein, called progerin. The issue therefore being in the protein rather than in the farnesyl group.
In the fictional world, we can think of a similar mechanism. The protein will be alright, instead another genetic mutation causes normal "good" farnesyl to be slowly turned into "bad" or "sticky" farnesyl. Over time, the unstuck "sticky" farnesyl is degraded and eliminated. The body of the raiders has no way to fix the "bad" farnesyl on its own, hence they have to find external sources for "good" farnesyl.
[Farnesol](https://en.wikipedia.org/wiki/Farnesol#Uses), which we will consider a precursor to farnesyl, is present in essential oils, and might even be addictive. The raiders need thus to search across a desert for **fresh** lemon-grass, boil it, extract the aromatic oils, cut them properly with other oils and reagents, and drink/inject/spread-on-bread on a very regular basis. All this not to whither like a mummy and live past their twenties. And the stuff is also addictive.
It seems quite a desperate life-style to me.
### Option 2: garlic/onions/spices to cover their very pleasant body smell
There are some very unpleasant sand-flies that spread a disease called [Leshmaniasis](https://en.wikipedia.org/wiki/Leishmaniasis). Simply put, a genetic mutation causes the raiders to produce a (very pleasantly scented) pheromone in their sweat that attracts the mites. In order to cover it, they ingest garlic, onions, and spices. Regularly and in large quantities. I know this is not exactly a deficiency *per se* as asked by the OP, but it is still a mutation induced condition leading to a desperate life-style. The choice is between stinking or being covered in blood-curling ulcers.
[Answer]
Aboriginal Australians were more or less employed/enslaved by the white settlers who introduced them to opiates in exchange for manual labour, were it a different drug like cocaine this could very easily have lead to tribal raiders armed with stolen guns raiding the colonists when demand exceeded supply.
[Answer]
Iodine.
In the midwest USA there was a major iodine deficiency due to a lack of iodine in soil, which lead to plants and animals being iodine deficient.
Some side effects of iodine deficiency in humans are, [congenital iodine deficiency syndrome](https://en.wikipedia.org/wiki/Congenital_iodine_deficiency_syndrome) which includes impaired physical development in children (Which your people apparently don't suffer from) and mental detrition in adults.
It's simple and easy. Your raiders come from iodine deficient lands. And need to raid the civilized people in order to get food that contains a trace metal that prevents groiter, and mental degradation.
They don't know why the civilized food tastes better and makes those that eat it smarter... But it does.
] |
[Question]
[
In my world the only available metal is copper and it is as rare as gold is for us. Other metals exist in salts and in rock, but ores and other common metal sources cannot be found for these elements. Noone can harvest metal from salts because reasons.
Due to the rarity of Copper, it would not be weaponised for the masses. It is plausible that a royal family or rich merchant may use copper for weapons, however my question is about the everyday soldier.
Up until the medieval era, weaponry would probably be accurate to on Earth. Knives and swords can be made from bone and wooden bows or crossbows would still exist. There could even be a cultural feature where people fashion new weapons from the bones of their enemies.
Siege warfare would be possible with siege machines, rams, and trebuchets all made from wood or similar. Even castles were built primarily from stone. Metal parts such as chains can be replaced with rope; portcullises can be made from treated wood.
My issue is advancing into projectile warfare and beyond. Gunpowder is possible, since the only metal it contains is in salt form (potassium).
Given that gunpowder and other explosives are possible using non-metal ingredients, I am allowing the use of explosives. Steam power is also feasible if a replacement for Iron can be found. Also, since copper magnets can be used to create motors and circuitry can be made using copper (or graphite?) it could be used in very small amounts to make computer systems.
**what non-metal equivalents to real-world weapons are possible? Would there be any weapons that we don't have, but this world would?**
[Answer]
Many weapons made prior to the industrial revolution can be made out of organics. I will start at the bronze age and move forward as that is where metal really began to take hold in military use.
* Bow and Arrows - bows are wood and string. Going to [Longbows](https://en.wikipedia.org/wiki/Longbow), or [Composite](https://en.wikipedia.org/wiki/Composite_bow) bows just requires animal materials
* Shields - wood, just use pegs, glue, and leather. Like the [ancient Egyptians](https://en.wikipedia.org/wiki/Woodworking)
* Swords - These are probably not possible except from [Macuahuitl](https://en.wikipedia.org/wiki/Macuahuitl)
* Spears - all we need is the tip, which can be [stone](https://en.wikipedia.org/wiki/Knapping), glass, or ceramic.
* Armor - early forms of leather armor are still viable. You could make [Lamellar Armor](https://en.wikipedia.org/wiki/Lamellar_armour) from wood or ceramics.
* cross bows - already given, but will reiterate.
* cannons - early ones in [china were made of paper and bamboo](https://en.wikipedia.org/wiki/Cannon#Development_in_China). There is even an entire page made for [wooden cannons](https://en.wikipedia.org/wiki/Wooden_cannon), the shot can be ceramic as it is easy to make a ball.
* guns - Online there are how-to guides for making wooden guns. I would assume if wooden cannons were possible handheld guns would also be. Rifling may not be possible though.
* Modern Armor(Bullet proof vests) - these are being made with [silk, kevlar, and ceramics](https://en.wikipedia.org/wiki/Armour#Present).
* Ships - until the 1850's, all were wooden. Most will be more fragile as you will need to replace nails for wood pegs and glue.
* Trains - Not possible to utilize the steam engine without steel.
* Hot Air Balloons - possible, [Unmanned balloons are easy](https://en.wikipedia.org/wiki/Hot_air_balloon#Premodern_and_unmanned_balloons), just the manned ones require storage for the fuel, this would be costly.
* Planes - without aluminum powered flight is not possible, [Gliders are available by replacing the frame with bamboo](https://en.wikipedia.org/wiki/Hang_gliding).
* Modern Armour(Tanks) - Combustion engine is needed, not possible.
[Answer]
I am assuming you're not really meaning "all metals" because they compose the vast majority of the [Periodic Table](https://en.wikipedia.org/wiki/Template:Periodic_table_(metals_and_nonmetals)); I assume there's scarcity of *some* metals, namely: Al Fe Cu Zn Sn Pb.
Most likely technical history of a world with low metal resources would diverge right at "bronze age".
It is very difficult to guess what "would have happened" with any degree of confidence, but I can give a few ideas:
* Wood and brick technology would proceed as in our world, possibly with some boost due to lack of alternatives.
* Glass technology would start as soon as in our world (it doesn't really need metal tools, they were used because available), but would have more push, so it's likely that it would have grown to overcome some of its "implicit" deficiencies (i.e.: fragility) developing glass foams and tempered glass much earlier, possibly to the point to implement glass weapons (surely for arrow and javelin heads, but probably also for swords (yes! a glass dagger!).
* Similar fate would have ceramic; probably it would become the main material for pipes of all dimensions. Tools made from ceramic would be more fragile, but almost as useful as cast-iron ones.
* Natural resins cements and the like would, probably, have a larger use and development because composite materials would be necessary much earlier to make up for the lack of metals.
* Industrial chemistry would have had a different development due to lack of high pressure containers (easier to produce with metal, but not impossible by other means).
* Electricity and all related technologies would be very difficult to obtain due to lack of ready-made conductors; carbon sticks (graphite) would be closest available.
* Using animals and plants to produce useful compounds (by hybridization at first, with genetic engineering if/when available) would be much more advanced due to (relative) unavailability of "traditional" methods.
[Answer]
While this isn’t much I do have a couple of examples of weapons without metals in them:
**Firearms:**
As you already mention crossbows will still be available but it would be possible to have some other firearms. In the 1993 movie “*In the Line of Fire*”, the bad guy played by John Malkovich attempted to assassinate the president with a composite plastic gun (SPOILER!). This gun came in four parts (to sneak past security) and consisted entirely of composite plastic apart from 2 high tensile springs because of this the gun was only effective at close range.
The bullets fired from the gun could also be plastic or wooden, as long as they were well treated so were light and effective.
The gun could then be made of wood as it relies on a spring not explosive material!
This could be fairly faithfully recreated (indeed is has been) with plastic springs however due to short range of effectiveness it would be more effective in a small shotgun style firearm. The potential energy of a spring when fully compressed is 0.5kx^2 (where k is the spring constant) which would be translated into kinetic energy of the bullet: 0.5mv^2.
However the momentum provided by the bullet is fairly small because of its weight and it would require a lot more force behind to improve the bullet momentum a small amount. Getting a spring that’s got double the constant of a previous spring would double its potential energy. So therefore the kinetic energy is double but if the mass is constant then the v^2 would be doubled meaning velocity would only be √2\*v and as momentum (p=mv) is mass by velocity then it would only increase to √2\*p also.
**Petrol Bombs:**
While petroleum usually contains trace amounts of metal it can be made without it, for the majority of petroleum is made of hydrocarbons.
The chemical breakdown of petroleum is as follows:
- carbon (93% – 97%)
- hydrogen (10% - 14%)
- nitrogen (0.1% - 2%)
- oxygen (0.1% - 1.5%)
- sulphur (0.5% - 6%)
- with a few trace metals
It would be possible to scale up the size of these bombs however the amount of petroleum needed would provide the greatest challenge for this world.
The container for these bombs would be largely irrelevant.
To launch these you would have to use catapults or such and the fuse would need to be well calculated for them to explode at roughly the right time.
[Answer]
There is a lot of focus in the answers about a chemical explosion projectile thrower. In our world, this is common because it's relatively easy and seriously effective, but it requires metals.
There are so many other lethal possibilities out there that don't require metals though.
The lack of metal necessitates that your people will be in the stone age for a very, very long time. In those days, the club was king. Just a good ol length of wood with a knob on the end. Lash a stone to the end, you get the primitive mace. Don't underestimate the mace. The kingly scepter, when you get down to it, is really just a shiny mace. Anyway, there are all kinds of things you can do with rocks to make them sharp.
Ranged weapons are easy. the bow, the sling, the Atl Atl, just picking up a rock and throwing it hard. These are going to be the weapon of choice pretty much forever, or until your people figure out how to refine the ores and metal salts.
Now we come to chemical propelled missiles. Why rely on throwing a lump of something faster than the speed of sound? Volatile substances are dangerous for many more reasons than that. If something can go *Boom* it can be weaponized. Clay pot grenades. Other kinds of bombs. A cloud of flour dust creates an absolutely terrifying explosion. Flamethrowers are very easy.
If you must absolutely have something menacing that uses gunpowder, Check out the Korean Hwacha.
I suspect that as you civilization advances, you are going to see a different track in warfare than our own. Yes, hand to hand weapons will be there, but you are probably going to get a lot of developments in poisons and flammables. I would also suspect a greater degree of sophistication in Animal breeding and training. We might actually see a ride-able combat bear.
Could be fun
[Answer]
Would there be any weapons that we don't have, but this world would?
Let's consider one of the greatest weapons of the bronze age that was overshadowed by the later invention of gunpowder: Greek Fire.
Some of the greatest advancements in weapon technology are based on potential energy storage beyond just the high ground and stronger warriors. The crossbow, Greek fire, the air rifle and gunpowder allowed a warrior of lesser strength and skill to overcome warriors of greater skill, but lesser numbers.
With an extreme lack metal tools, most structures and forts would be made of wood and not cut stone. Thus Greek Fire would be as, if not more, devastating than gunpowder grenades.
To counter Greek Fire people would experiment with fireproofing, such as armor made from Asbestos, wool, oak, plaster and later Nomex.
Military tactics could evolve quickly. The bronze age phalanx formation, which continued to Napoleon and the American Civil Wars, used masses of soldiers working close together, and when one falls another takes their place. With Greek Fire, the fallen warrior is on fire. Also Greek fire can splash and is sticky. Thus the tight formations of a hundred or more men would be abandoned for trench warfare and squad tactics.
[Answer]
What time are we thinking about?
My thoughts regarding weaponry would be the following, as you move through history:
The bow and arrow (and related weapons) would be king for much longer than in our world. Artillery would probably consist of large bows and catapults; the catapults would become increasingly deadly with the advent of explosive payloads. Rockets would likely develop a little faster as weapons due to a lack cannons.
The really big revolution though would come with the advent of higher-technology plastics. With the likes of carbon fibre and kevlar, guns as we know them (albeit rather more expensive) would start to become possible - and probably create a sudden leap in lethality, as any civilisation able to make such plastics wouldn't be starting at the musket but straight in at modern weapons.
However, how long it would take humanity to successfully make plastics in the absence of metals is a much more complex question, I'd certainly imagine that it would be a lot slower. Could the industrial revolution happen at all without metal?
[Answer]
Force trauma is how most wars are fought in our world, but in yours I believe an emphasis on organics would come into play. Poisons, venoms, and diseases would prove relatively easy to make, and fairly effective for some protection, battles, and wars.
This style of combat, however, is slow. Force trauma can disable an active attacker, but poisons take time to act.
Therefore the style of warring might be more akin to cloak and dagger arrangements - spying, slowly poisoning, injecting poisons from afar using arrows, spears,or other ranged weapons.
People would still use wood and stone for close combat, but I suspect an emphasis on poisons would come into play much more than we have seen in our society.
[Answer]
You have calculated things ghastly incorrectly. The technological development of these people would never reach the medieval era. Metal has been the primary fuel driving the technological evolution. Without metal, these people would be stuck in something between the dark and neolithic ages.
You are right that battering rams can be built with wood and stone. But how are you going to cut the wood so precisely? With obsidian knives and axes, right? Yes you can, but obsidian blades get blunt very quickly and you have to chip them off again and again very soon until they get too thin to be useful anymore. Plus, obsidian is a rare substance, found only in volcanic regions. Read about the technological level of the Aztecs and Mayans. That should give you some insight into how advanced (or not) a civilization can get without metal. And then again, Aztecs and Mayans did have pure gold and silver to use, and in the past, had evolved Asian people no farther back in time than 12000 years ago or so.
---
Anyway, that was a tangential discussion about how advanced your people can get. Now back to the topic of warfare without metal.
**Melee Weapons**
Talk about wooden clubs. The royals and officers would have their clubs spiked with obsidian and rock. That is going to be your primary war weapon at close range.
Another weapon would be short leather whip, with shards of sharp rock and obsidian glued to it.
**Ranged Weapons**
[Atlatls](https://en.wikipedia.org/wiki/Spear-thrower) would be very common for launching javelins. While atlatls usually tend to decrease the accuracy when used for maximum range, a whole legion of atlatl throwers would do devastating damage as hundreds of atlatls are launched from distances of about 100 - 150 meters from both sides.
Also, there might be legions of people adept in [throwing knives](https://en.wikipedia.org/wiki/Throwing_knife). While the range of throwing knives is far restricted than those of javelins, they would still be used for sudden hit and run tactics and guerilla attacks.
Yet another weapon which would get a lot of importance is the [blowpipe](https://en.wikipedia.org/wiki/Blowgun) and dart. Accurate, but having short range, it would be another weapon of choice for guerilla attacks and diversion tactics.
The bow and arrow would (obviously) be the most powerful and accurate weapon. It would obviously be impossible to develop the powerful modern composite bows, but classical composite bows such as Mongolian and Turkish would be possible. These would require a lot of time and effort to build, but would be highly prized weapons of choice in a war. Considering that metal is not available, arrowheads would be either made of hardwood, horn, thick plant thorns or carefully chipped rock.
**Poison**
Poison would be the secret to winning wars. Fast acting, debilitating (in a battle, fast action is more important than lethality) poison recipies (such as those incorporating aconite and strychnine) would be kept secret and highly prized.
Poison would be applied to all types of range weapons, javelin and arrow heads and on the ends of darts. Wars might be decided not on the basis of numbers, but on the basis of which party has faster acting poisons.
**Gunpowder??**
I don't think your people would be able to make clean, factory grade gunpowder, because of the requirement of hydraulic press, which can *practically* only be made with metal. Your folk could concoct a crude mixture of black powder (potash nitrate and coal), but the type required for use in canons would be impossible.
It *might* be possible to make some type of a very crude (and extremely short lived) canon or matchlock guns, but that too, is extremely unlikely as making smooth holes in long, thick logs is extremely difficult and error-prone effort in a metal-less world. Those people would not have the pipes available easily to start experimenting with them in the first place, to invent canon.
Black powder would be quite useful in bringing down fortifications though. And in guerilla attacks where it would be used as distraction device and to blow up enemies in ambush attacks.
[Answer]
I think that without metal you get tech levels similar to aztecs and Mayans.
There is one material that would do wonders for your world:
nanocellulose
The properties of nanocellulose are listed below:
• Lightweight
• Stiffer than Kevlar®
• Electrically conductive
• Non-toxic
• The crystalline form is transparent, and gas impermeable
• It can be produced in large quantities in a cost-effective manner
• It has a very high tensile strength - 8 times that of steel
• It is highly absorbent when used as a basis for aerogels or foams.
• The raw material - cellulose - is the most abundant polymer on earth
<https://www.azonano.com/article.aspx?ArticleID=3139>
it's production process, as described in the article is quite easy and it's highly cheap, with at modern currency values it being only a few dollars per pound, cheaper than steel.
Your people could make light, efficient body armor that would be able to withstand nearly any weapon an enemy can throw at it including even firearms.
It is transparent so you can create windows and doors that are nearly impervious. It can even possibly make optics and telescopes.
You could create a tissue like film and use it to dress wounds.
You could make a form of paper.
versions of it are edible.
If you look at this wikepedia article and go to the applications section it will show you hundreds of other uses:
<https://en.wikipedia.org/wiki/Nanocellulose#Applications>
[Answer]
The Māori people of New Zealand used non-metal weapons prior to the arrival of European settlers.
They used wood, stone, bone and other materials to form various weapons.
The Taiaha (fighting staff) and the Patu (club) are probably the most well known, but there are others.
I don't believe the Māori used archery though it would certainly be possible to make arrowheads using stone, bone or teeth.
This link should give you a little more information:
<https://teara.govt.nz/en/riri-traditional-maori-warfare/page-3>
It might be possible to carve small cannons out of rock but I doubt they would withstand much explosive force without failing.
There may be some way to use weights and pulleys to increase distance and power of ranged siege weaponry, but I've no idea how this could be accomplished.
Perhaps balloons could be used somehow.
] |
[Question]
[
I'm writing a species of dragon-sized butterflies¹ as flying mounts into a low-magic fantasy setting², and would like to know if these creatures *have* to be imbued with magic, or if they could just be mundane through some contrivances. What stands in the way of having an *insect* of this size, and how can we get around it?
I recognize that [this question](https://worldbuilding.stackexchange.com/questions/313/how-could-dragons-be-explained-without-magic?noredirect=1&lq=1) deals with the square/cube law, and the implications it has on creatures of this size - I was just wondering how it differs in the context of insects (Lepidoptera specifically).
¹ I'm looking for sizes ranging from 10-22 feet in height, and 40-150 feet in wingspan, varying by species. I **don't** mean to have Kaiju-sized butterflies.
² Assume conditions analogous to middle-age Earth (with the addition of magic)
[Answer]
On an Earthlike World they would need magic. Butterflies like all insects are constrained in size because they don't breathe like us.
Basically they have small holes and tubes all along their bodies so air can get in and be absorbed directly into the tissues. This is fine at small scale, but becomes exponentially more inefficient at larger sizes.
Here is a link to explain how their gas exchange system works [Link](https://en.wikipedia.org/wiki/Respiratory_system_of_insects)
Getting around this problem would mean a complete redesign of their gas exchange system... or..... magic.
[Answer]
The dynamics of flight depend on the scale, too! Even if you redesign the animal to exist in a large size, and make it large and strong enough to lift a human as well, you will then need suitable wings.
Look at how bird wings differ by size: and that’s just within birds. You simply could not make a paper-thin wing articulated with a tiny joint, in that scale.
Besides the biology being nothing like an insect inside the body, the flight surfaces will *look* nothing like a butterfly.
---
What if dragons (without magic) are also really tiny, and a “scale magic” is used to make them big? The people learn to apply the same scale magic to butterflys, as they make better domesticated mounts.
[Answer]
Besides breathing and flying, another issue is the diet.
A butterfly does not "eat", it only drinks, by unfurling a curled up tube called a proboscis that acts like a straw. It feeds on anything that can be dissolved in water, including plant nectars and saps, pollen, rotten fruit and even dung and human sweat.
I can see several issues with this:
1. A 20 foot tall butterfly would probably need a proboscis of at least 10 feet, which may cause problems with sucking up fluids through such a tube, no matter how wide it is;
2. Where is the butterfly going to find enough nutritious liquids to sustain itself? It could probably slurp down an entire vat of fruit juice and still be hungry;
3. How is the butterfly going to access the fluids? nonmagical plants probably aren't going to be able to provide a gallon of nectar a day, and even if they do, it'll have to be in a way that the butterfly can access.
[Answer]
Instead of giant butterflies, you could have tiny humans. The butterflies and dragons, while small compared to normal sized humans, would appear several times bigger than very small humans. Of course then you have to deal with humans living in a much larger environment surrounded by giant flowers and other such things, but that could make for a unique premise as well. This would help deal with how the butterflies feed, breath, and fly since the flowers would continue to be normal sized and their bodies would function as they would now.
You wouldn't run into the common square cube law issue, but as indicated by [this answer](https://worldbuilding.stackexchange.com/a/58357/14532 "this answer"), at such tiny sizes you run into the issue of humans overheating. You could gloss over that a bit easier by claiming humans in this environment evolved better heat dispersal or perhaps were artificially created or enhanced to disperse heat better. If you actually have dragons in this environment as well, you already have an existing creature that has a highly refined body heat management system. Either way it's a bit easier to handwave than the square cube law.
Basically, the dragons are butterfly sized, but the humans are tinier.
[Answer]
>
> How can we have dragon-sized butterflies?
>
>
>
By stipulating butterfly-sized dragons.
Or, if it's the size of butterflies relative to the rest of your cast you're interested in, by scaling your cast down accordingly.
>
> What stands in the way of having an insect of this size, and how can we get around it?
>
>
>
1. Respiration: increasing atmospheric oxygen content, per Mitch Connor's answer, gets you to seagull-sized, but past that you'd probably need to give them a not-very-insect-like pumped respiratory system. Either that or they're going to be so perforated for gas diffusion, they'd be more like a terrifyingly fragile elaborate chitinous filigree than a solid body, at least when you get close.
2. Structural strength: the general square/cube problem with exoskeletons remains even with higher oxygen content. The filigree solution might work here too, actually, but I'm not sure how similar it'd really be to a butterfly
* structural strength of the wings is probably more of a problem, because they need to be at least solid enough to displace air. A highly-perforated body (for strength:weight and respiration) also has higher drag, which probably doesn't help with flying. Maybe they could just glide on thermals or something?
On reflection I quite like the filigree approach, but it'd look more like a roughly butterfly-shaped bio-mechanical steampunk contraption than an insect.
[Answer]
Make the air density greater than it is on Earth. Aluminum foil can float on sulfur hexafluoride. With greater air density, you can have greater buoyancy.
<https://www.youtube.com/watch?v=1PJTq2xQiQ0>
[Answer]
You can start by making them light as the atmosphere around them. For example assume they consume helium from a none atmospheric source; and store it in their cells, making each cell into a tiny Helium balloon.
There is still the question of inertial mass - so make them slow moving. Maybe lowering atmospheric density will also help, by lowering friction.
If you want them to carry things, such as passengers, they'll have to be able to compensate for the additional weight, by regulating the amount of helium in their cells. Another option is to make them lighter than the atmosphere around them, and carry some substance as basalt, again, on a cellular level.
[Answer]
Interesting thought: Does the dragon-sized butterfly need to look EXACTLY like a real-world butterfly?
Many realistic dragons have strengthened and thicker wings, joints, and bones. In a world where a 20 foot tall butterfly can exist, the butterfly wasnt magically enlarged from a smaller one. It grew and evolved over time, of course assuming the necessary food sources are there.
So if you find and eliminate all constraints to nourish and feed a giant butterfly, then there is no reason the biology of the butterfly can't evolve to make use of that.
Also to note, for an environment with the proper oxygen levels and large flowers with large nectar stashes that can sustain a butterfly, there must also be a either a much larger predator for the defenseless butterfly or a defense mechanism that makes it something like an elephant, giraffe, moose; not an apex predator, but enough strength to defend itself from one.
**EDIT:** Didn't see the second footnote regarding middle age like world. Umm, make them native to a patch of magical forest that has the necessary oxygen levels and nectar resources. They can stay alive for a number (24?) of hours in a normal oxygen level. The food can be resolved either with a magical bottomless bag with lots of nectar stored or some sort of high density / high energy nectar created by magic.
Basically you'd have a naturally large butterfly that is only sustainable through a certain location or with magic.
[Answer]
**Can your world survive caterpillars the size of school busses?**
You need two things especially:
(1) increased air density relative to gravity.
(2) An ecology that can support the huge, ravenous CATERPILLARS implied by your butterflies.
Increased air density, relative to local gravity is key to scaling up your butterflies, as has already been mentioned. Does your world have to be a planet? Consider alternate venues, such as in a closed, albeit huge environment, such as the interiors of the living Titans in John Varley's Gaea Trilogy. See:
<https://en.wikipedia.org/wiki/Gaea_trilogy>
or in the no-solid-ground 'smoke ring' of Larry Niven's Integral Trees:
<https://en.wikipedia.org/wiki/The_Integral_Trees>
---
You also need an ecology that can feed both the larval butterflies (caterpillars) *and* your protagonist species. Doing so may not be so easy, with realistically voracious giant caterpillars.
Caterpillars are voracious consumers of leaf matter. Is there a mechanism that allows humans (or other, non-caterpillar/butterfly protagonist species) to have something to eat, with those giant plant vacuums all over the place?
[Answer]
Well... when you consider that dragons themselves are unscientific... i.e.:
it does not make sense for them to be able to fly with their size and weight.
Most stories have them flying with the power of magic. With magic as the answer, any answer can make (non)sense :-)
That translates to: yes, you can have butterflies the size of skyscrapers, as long as you use magic to answer how it is possible.
Edit: Well, I am new to the arena. So I do not think I can really provide anything more scientifically to the answer. Secespitus is right.
My answer has already been provided. And as someone who knows jack all about insects and how they breathe, I cannot provide any more useful insight.
But let me try to add on to what has already been provided, the only missing ingredient: how magic could help.
If insects do breathe using micro holes, have their breathing be handled completely through the use of magic - with magic being used to act as a *black hole* of sorts for air.
If the holes in the insects body increase in size proportionally, you could even have it such that anything that gets sucked into the hole, gets broken down into energy/required material (such as protein/ vitamans/ etc.) - which could even be used for their protection.
] |
[Question]
[
Gallium is a metal that melts at room temperature.
I have a character who has the ability to manipulate matter and temperature to some degree. Is it possible for her to carry around a sheathe full of gallium and alter it into an effective sword?
Her environment is usually lower than gallium's melting point
[Answer]
Regardless of the temperature, Gallium is a poor choice for a sword.
Decoding its properties from Nex Terren's comment link:
<http://www.azom.com/properties.aspx?ArticleID=1132>
## Some of Gallium's mechanical properties:
[Tensile Strength](https://en.wikipedia.org/wiki/Ultimate_tensile_strength) - How strong is it, or how much force does it take to pull it until it breaks:
15-40 MPa (compare to polyethylene [AKA plastic] 12-43 vs steel 500-2000)
[Hardness](https://en.wikipedia.org/wiki/Vickers_hardness_test) - If you poke or scratch it does it deform:
50 on the Vickers scale (most hardness comparisons start at 80, it's a pretty soft solid - easily deforms or scratchs)
[Young's Modulus](https://en.wikipedia.org/wiki/Young%27s_modulus) - how easy is it to deform:
9.6-10 GPa (Most comparable to wood 11, again easily deformable. Most metals are 100+ steel is around 200)
[Poisson's Ratio](https://en.wikipedia.org/wiki/Poisson%27s_ratio) A measure of how much it deforms, ranging from 0 to 0.5:
0.47 (Most hard metals are much lower 0.2-0.3, it's similar to saturated clay 0.40–0.49, or Gold 0.42–0.44.)
## Conclusion
Your sword would be solid but would easily bend if put under stress and would likely break if swung or used to block. I don't think it would be likely to shatter (it's not hard enough), it would just bend and break more like a plastic or gold sword than a glass sword.
Beyond its general weakness, I'm not even sure if you could sharpen it using any traditional means (it would likely melt from friction heat at the edge if you tried a whetstone). You could cast it into a blunt pointed/edged shape, but I'm not sure it would be worth it, as any minor handling would quickly bend or blunt it.
[Answer]
Melting point is not among the first concerns when picking materials for a weapon, ductility, malleability, and brittleness are. In the case of [gallium](http://www.chemicool.com/elements/gallium.html), where you run into trouble is with the brittleness. Even if your heroine is able to keep her sword as chilled as she can, as soon as she strikes something hard with it, it will fracture in her hands.
[Answer]
One issue is cost. Google says gallium is around \$220 per 100g, so around 3-4 times more expensive than silver. Reckoning on around 1kg for a rapier, that's going to set you back around \$2k. This seems excessive.
The obvious question your character is going to be asked is "why do you have a bagful of this relatively expensive metal?" If you're trying to sneak around without your weapon being noticed, this is a bad idea. Plus metal detectors, if we're in a modern-day setting.
A much better solution is simply to carry a water bottle. A couple of litres of water can then be turned into a very effective mace. For an even better version of this, flow the water over a rolled-up newspaper to make a [pykrete](https://en.wikipedia.org/wiki/Pykrete) weapon which is very much stronger than pure ice. With a rolled-up newspaper, you could shape this as a club/mace, or taper the newspaper to make yourself a rapier.
[Answer]
You can always say it's Gallium alloy. I doubt anyone knows every and single Gallium alloy properties; and the alloy in question doesn't even have to be Gallium majority, it's enough for it to be the most interesting metal in a bunch to be called so.
[Answer]
I wouldn't think this would be practical. If her sword is in contact with an enemy (skin, blood, organs, other gross stuff) for even a short period of time, it would start to melt. If an enemy could get a hand on the sword's blade, he/she could hold it for 2-3 seconds and then remove the blade from the hilt.
[Answer]
I would think the ability to keep the sword cool enough to be used would be a more effective weapon than the sword itself.
Gallium, like water, expands when in solid form (instead of contracting/shrinking, like most everything else), and as a metal it would be too brittle to strike or slash. Maybe stabbing would be fine. Consider a dagger.
[Answer]
At room temperature it's rubbish but I can't find any information on it's physical properties at low, like liquid helium low, temperatures. It could perform very well if you were fighting a goo monster on Triton where the summers are a balmy negative two thirty Celsius but no-one's ever been interested to test that weirdly enough.
] |
[Question]
[
I'm working on the story of someone born in the tunnels after the earth has gone though a runaway greenhouse effect.
I want these tunnels to be real, with real infrastructure to keep the inhabitants alive.
There's a mountain of research to do, but the big question I have to start with: "Is this even possible?"
I was thinking that the tunnels would need to be completely sealed from their surrounding environment, like an underground spacecraft.
I am hopeful that you can still exchange heat with incinerating temperatures.
Is such a heat exchange possible?
In my imagination I'm seeing giant metal arm nearly glowing deep red, moving a soft metal short-lived piston though a harder metal cylinder. But I don't know what it's pumping, or at what temperature and pressure.
[Answer]
There is no reason not to live above-ground in well-insulated and cooled buildings. As far as the infrastructure goes, that's clearly *much* simpler. The reason it's not crazy is that the effect of insulation has an exponential relation to the thickness: Say, your house is in Canada and its insulation reduces the heat flow from 20°C inside to -20°C outside — a temperature difference of 40K — to 10% compared to being uninsulated (probably conservative). Now that the outside temperature rises to 260°C, the difference is 240K. Heat flow is roughly [proportional to the temperature difference](https://en.wikipedia.org/wiki/Newton%27s_law_of_cooling), so with a 240K difference you'll have 240/40=6 times the heat flow. *Less than doubling your insulation*, cutting the heat flow by another factor 10, should deal with that. Of course you need an A/C that can shed the same heat than your old heater generated, much more than an A/C typically can, but you can just add *another* layer of insulation. You now have 1m or so rock wool in your walls, and the outer surface is most likely neither wood nor PVC nor asphalt shingles, but that's OK.
You also don't need to insulate yourself from the atmosphere; once chilled it will still be breathable, potentially after filtering out smoke from the still-burning Tundra. You could use heat exchangers with outgoing air to pre-chill the incoming air before actively chilling it further to room temperature, effectively using a technology in reverse which is [already in use today in low-energy houses](https://www.ag.ndsu.edu/publications/energy/air-to-air-heat-exchangers-for-healthier-energy-efficient-homes).
Because of the [cube-square law](https://en.wikipedia.org/wiki/Square%E2%80%93cube_law) there would probably be more larger apartment buildings and fewer single houses. You could even have windows; they would likely be small and [infrared absorbing](https://www.newport.com/f/heat-absorbing-glass-filters), and would need internal cooling, probably by an embedded mesh of cooling fluid. The rest of the house would have reflective coating. Looking out through a normal glass pane would feel a bit hotter than looking into your kitchen oven at full throttle: Doable, but not for long. You also wouldn't want combustible materials close to the window; so it's safer to have infrared absorbing glass. At night and during storms (and there *will* be storms) you'd close tightly fitting shutters for more insulation and protection, just like you do in harsh cold climates today (except you wouldn't use wood).
Insulated and cooled vehicles or even something resembling bulky spacesuits (also with insulation and cooling) would make it possible to still enjoy the great outdoors. The infrared-absorbing windows and visors would also need internal cooling, like the windows in the house; or you switch to cameras and monitors/VR.
[Answer]
Heat can be dumped into an area hotter than the area being cooled; if that weren't true, we wouldn't have refrigerators.
Now, these would have to be spectacularly good refrigerators. Normal refrigerants probably would be insufficient, and they'd be on permanent cycle, and their failure wouldn't just involve a call to Maytag.
Happily, 500F isn't all that hot. It's oven-hot, but well below the melting point of most metals. Iron won't even be red-hot (sorry about your mental image). So you won't need any unusual materials in construction.
It would be an existence balanced on a knife edge, and "diggers" would still need somewhere to dispose of their spoil, but it doesn't seem impossible.
[Answer]
Short and imprecise summary of refrigeration: A refrigerant is compressed, causing it to heat up. The heat is shed by pumping the compressed refrigerant through a radiator. The cooled compressed gas is then pumped into the cooled area and depressurized. In order to expand it must heat up, which it does by absorbing heat from it's surroundings. This is why deodorant is cold. The refrigerant is then pumped out and compressed again, allowing it to reject the heat it absorbed
Engineering a system like this for such a situation is difficult, but by no means impossible, probably even with current day technology. (I was thinking of a multi stage system with a couple different refrigerants hooked up to a coolant loop, but nevermind that.) What would be more difficult is heat management.
Cooling is very power intensive, probably even more so in the setting you're describing. Using any method of power production that produces significant waste heat (i.e. heat not converted to electricity or motion) will eventually become a problem. Using the ground as your heat rejection medium will also work only for the first couple of decades, until the bedrock slowly gets to temperatures similar to those of the atmosphere. Going deeper will find you getting increased temperatures as seen in the gold mines in south Africa. Basically you need a system that produces enough electricity and a small enough quantity of waste heat to cool itself. (This is not a perpetual motion machine, it is still being fueled externally)
Any kind of thermoelectric generator would likely be a bad idea, therefore burning biomass, geothermal and the temperature of the surface are all out. You will have to consider using thing like photoelectric (solar panels), wind and possibly aneutronic fusion, depending on how science- fictiony your setting is.
Another option would be to have your nuclear plant run hotter than usually practiced today and have it out on the surface, cooling down its coolant to the temperature of the surface at which your coolant is liquid, and then heating it back up to insane temperatures again, boiling, running through a turbine etc. This would give you an excuse to have red hod tungsten carbide pistons pumping around gaseous corrosive salt or tin.
[Answer]
No intrinsic problem:
Given enough expense, the only limitation to a refrigeration system is that the place where you dump your heat must not be so hot that your hot-side of the refrigerator gets destroyed.
Also, your power generation method must not create more waste heat than can be handled, either by dumping into the environment (the usual way) or be pumped out using your refrigeration system using the same power that was just generated.
As your system uses Thorium reactors, which run at 650C++, they will work just fine using the outside ambient of 260C to dump heat. No problem there. None of the power generated by your reactor need to be wasted in an inefficient refrigeration scheme.
The whole setup will be silly expensive, of course. And will require really, tremendous huge number or size of power reactors, but it can be done. One advantage of having the surface being a hell-land, is that you might not mind contaminating it with radioactive and chemical wastes, which will serve to simplify your industries and power reactors *a lot*.
As for the visual effect you are looking for: The scheme by thewildnobody above is a perfectly valid excuse/reason to have such. One mode of Thorium reactors works with redhot molten salts as the reactor core, and if you don't mind the radiation you can quite efficiently pump the actual reactor core material around.
P.s.
I hereby UN-volunteer myself for a surface inspection and maintenance squad. That would be one of the least desirable jobs in the whole universe!
[Answer]
# Mountains
As others have noted, cooling 250 C is quite feasible using existing technology. After all, scientists quite regularly cool experiments to near absolute zero, which is more than 270 C below (water) freezing. Most [MRI machines](https://blog.se.com/healthcare/2018/03/23/mri-machine-cooling-reliability-patient-satisfaction/) use liquid helium\* cooled superconducting magnets and can operate essentially 24/7 in a hospital environment. Note that the insulation required to maintain this temperature is not absurdly bulky, as Peter observes.
Even so, I would suggest that your inhabitants, rather than digging underground, instead burrow into mountains. There are several advantages. First, the mountain provides a large natural thermal barrier, reducing the amount of insulation required for human structures. Second, we already have a ton of tools and experience digging into mountains. And third, the coldest heat sink accessible in such an environment is most likely going to be high-elevation atmosphere.
# Solar Chimney
So, your inhabitants will most likely want to build a mega-project somewhat like a massive [solar chimney](https://en.wikipedia.org/wiki/Solar_chimney) at the top of the nearest/highest mountain. The chimney should be as large as they can afford to construct it, both in terms of height and cross-section. Unlike a traditional chimney, they actually want bidirectional flow, so I would suggest a coaxial design where an inner pipe moves cold air from the top downwards, and the outer section moves exhaust heat upwards.
The theory here is that exhaust heat will be hotter than cold intake heat, and so you want that in the jacket layer, closer to the hot outside air. You want to protect your cold intake air as much as possible. Note that "cold" is relative, and may still be 100+ C at the altitude they can build it.
The top of the chimney should be forked, so that hot exhaust gas can be blown downwind of the cold air intake, and the exhaust vent needs to be able to rotate in response to prevailing winds.
Being able to dump waste heat into air which is 100 C colder than ambient will be a significant energy savings.
Even if your inhabitants cannot afford to build a tall chimney, they can still use the mountain itself as a chimney, either with a rotating external vent, or with multiple vents built into all sides of the summit, and an internal mechanism which can rotate to vent/intake from different ports. But if they have multiple thorium reactors to power their civilization, then they have the tech and resources to build a pretty big chimney.
# Ocean
The bigger problem, IMO is water. You haven't said how long the atmosphere has been 500 C, but eventually, you will boil away the oceans. Until then, you could use the deep sea as a heat sink, if you don't mind accelerating the loss of water. Most likely, the thermal output of your remaining civilization will be a drop in the bucket compared to the atmospheric thermal load.
But the lack of rain means that your civilization will have just as much problem keeping water as it does staying cool. Fortunately, the boiled oceans will mostly stay in the atmosphere, making the air completely saturated with water vapor (and probably quite unpleasant to breathe, as it will be super-heated vapor which likely burns your lungs). However, this also gives you a source of water, since you can just take in outside air at whatever elevation has high vapor pressure, and condense the water out of it. Basically, make your own rain.
Good luck!
\* Helium boils at 4 K
[Answer]
Simple real-world example to show it's possible:
Your temperatures are not far from has already been done many decades ago. Specifically, the cockpit of the SR-71 spy plane. It was more efficient to put the pilots in basically spacesuits and cool them than it was to cool the whole cockpit.
It will be much easier on the ground because you aren't meaningfully weight or size limited, you can replace power with insulation.
[Answer]
In addition to refrigerating the living compartments, you will need to move waste heat from the reactors out (significant amount). Note that 500F is pretty close to normal temperature of a steam cycle (for a nuclear plant). So, you'll probably need to use conventional cooling (say water recirc) and then massive refrigeration of the heated water. This may dwarf the heat transfer required for cooling the insulated dwellings.
[I guess you could also imagine some sort of nuclear process using much higher temp fluids and then directly using 500F air for cooling. But I suspect the materials issues in developing higher temp reactors, turbines, etc. (especially on the secondary side) would be much more challenging than just using a conventional system and then cooling the cooling fluid via (more of) the same refrigeration method you use to keep the people safe.]
P.s. I don't think thorium is needed or optimal. You could use conventional uranium fission reactors. Probably a lot easier than thorium. (After all there is a reason why they win now--read the Rickover memo on "paper reactors".) If you are concerned about exhaustion of ore, breeders are the natural go-to. I would think that option would happen well before thorium. Also, presumably, you posit a much smaller society than the world's current population.
[Answer]
I think going underground is good, because it is colder further down. Then there is no need for air conditioning and special materials for insulation.
The hot air is full of water, which will condensate when the air is pumped underneath. All food production would need to go underground. This needs a lot of water. You need to pump a lot of air/water gas and then you need to pump a lot of water back up. The used water evaporates and drives turbines.
The temperature difference from below ground to atmosphere as well as within the atmosphere (winds) are energy sources. Maybe no nuclear reactor is necessary.
] |
[Question]
[
I have a slug that I need to kidnap. Not an ordinary garden slug; this slug is special. This slug's slime is violently reactive with the atmosphere on my planet, and explodes into flame on contact with the air. The slug breathes oxygen, but doesn't need very much (or else it would suffocate). It also can be knocked out/made high on chemicals. This slug continually grows, with mature young ones being the size of a beaver and ancient ones being the size of a horse's body (excluding leg height). I'm aware this causes problems with the square-cube law, but we'll ignore that for now.
The slug's movement speed is quite slow, maybe about 5 meters an hour, and pouring water on the slime inhibits, but doesn't totally prevent, the reaction--even when totally submerged. Oil-based compounds do not react with the slime, although they can be started on fire by coming into contact with fire; if you could submerge the slime in oil totally without lighting the oil on fire, it wouldn't burn.
This slug lives in an old-growth forest where the trees are fire-resistant, but not fire-proof. Think something like a Jack Pine, where fire not only doesn't harm healthy trees, but is necessary for reproduction. The slug is followed by a trail of fire wherever it goes that burns out on its own relatively quickly (in general, think a day or two). Stones are available in this forest, but not in all locations.
I also have a hero or two who are considering capturing this slug and transporting it with them for at least a few miles. The problem is, they are in the middle of a forest with nothing but a staff, a knife, and a skin for water. They can make additional materials, such as a net, but they cannot bring any others with them from "civilization". **How will they restrain and transport the slug while keeping it alive?**
### Answerers:
In the story heroes can unlock access to magic they can control with their thoughts, but these two heroes are not willing to unlock their access at this point; answers proposing they use this magic to carry the slug away will not be accepted. Additionally, it is OK to say they can't do it; I'm not committed to having it kidnapped just yet.
The whole story can be found at [Story-go-round](https://chat.stackexchange.com/rooms/70113/story-go-round).
[Answer]
You could build a relatively shallow [pit fall trap](https://en.wikipedia.org/wiki/Pitfall_trap). You don't want to slug to fall very far or it will be injured, but if the hole is only a little deeper than the slug's ability to lift its front then it will do the job. The hole should be undercut so that the slug cannot just climb the vertical wall out.
To get the slug in the hole either use a corralling process, sharpened stakes of fire resistant wood for example, or bait hung above the hole and a lot of patience - a slow slug is going to take time to get into the trap regardless. The slowness of the slugs is also an advantage since you can build the trap relatively close to a known slug without it getting away from you. You will need to observe your prey for a while to work out how deep the hole needs to be.
If you have time to move your now captive slug then you build a path of least resistance: dig out one side of the trap and wait for the slug to follow the path. Keep bait and/or something pointy handy to encourage its acceptance of the path.
If you need the slug elsewhere in a hurry [lard](https://en.wikipedia.org/wiki/Lard) is your friend. For a little while at least you can cover the slug in tallow to exclude oxygen and prevent its combustion long enough to take it away. To transport it you'll want a tub sling of some kind, probably made of oiled canvas, deep enough to keep the slug submerged in fat. You can set such a sling up on shafts and have a pair of horses, fore and aft, carry it attached to an appropriate harness wherever you need to go.
[Answer]
*Treating this as an otherwise ordinary giant slug*
You need some bits and pieces:
* A barrel of beer
(Not usually available in the middle of a forest)
* A barrel of salt or sharp rocks
(Rocks you can gather, salt not so much)
* A pointy stick
(This at least should be easy)
The biggest problem is speed, your slug is too slow. Beer makes gastropods move faster, hence it being banned from snail racing events. It doesn't really make that much difference in the grand scheme of things but a drunk slug is a happy slug.
Lay track boundaries of sharp rocks or salt, neither of which gastropods are fond of moving over. Salt is more effective but also more expensive and harder to get in such quantity.
The pointy stick is for general encouragement.
[Answer]
You have a Staff, that should be enough. It's a slug, I'm going to assume not terribly bright.
Use your staff to prod it and goad it, it'll turn away, if it doesn't, plant the staff in its way and it'll have to turn.
In this way, guide and goad it down the path to your destination.
What? You're in a hurry? 5 meters an hour isn't good enough? you want to get there within a month and a half? Uh...
Okay.
What you want to do is find a furry beast of some description. A Squirrel or maybe a possum. Kill it, Skin it, Tan it as best you can, soak the skin in water, particularly the fur. snatch up a small slug (say: a few inches long at most) and put it in the fur. it'll smoulder but leather/flesh is really good at not burning. especially when it's damp.
Basically you have a wet bag you can carry.
Now start running.
When it starts to seriously smoulder, drop it, eject the slug onto the dirt. soak the skin again, put the slug back in the bag and continue.
A few miles can be covered easily in an afternoon on foot. An hour or two at most with breaks.
Less if you're running most of the way.
Once you get there, what you want is a stone basin, a dried up fountain would do great, or a horse-trough.
Dump your slug in that. line the perimeter of the interior with rock-salt to deter it escaping, leave some leafmould or something for it to eat.
Enjoy a cold beer while you cool off after your epic run.
Mission Accomplished.
[Answer]
They can use the fire resistant trees.
They cut branches with their knives and make a little cage to kidnap a baby slug. They make small holes in some branches and can put other branches inside and use the bark to make some rope to attach everything.
They place a cage really near the slug and they throw some rock at it to make it run slowly in the cage. They use large branches that cross the cage as a support point to lift it and stay away from the fire. If the fire spreads to close to their hands, they use some new large branches as supports.
They will lose some time building the cage, like maybe half a day, but will gain so much more time in the end. They need to travel a few miles, take for example 2 miles (3218.69 meters). The slug runs 5 meters per hour, so it will takes almost 644 hours to go to their destination if they try to make the slug runs by itself. But, with the cage, even lifting a slug the size of a beaver (30kg), they still can walk 1-2 miles per hour easily and go to their destination in only 1-2 hours.
With the knives and the fire resistant trees, you have everything already to do it in one day.
[Answer]
Slugs emit two kinds of mucus, one kind from their feet and another kind from the rest of their body. I assume the explosive kind only comes from its feet, or the slug would be entirely on fire.
So, for an exciting catch, I'm thinking they could take two very long sticks and bind them together at one end with vines or some kind of rope, and then put a short, fat stick in between them at the joint, bound to only one of the sticks so that when they bring the sticks together they make a tiny little triangle at the end with the smaller stick. (The three sticks would be shaped like a long, skinny 'A' when together.)
What they can do is sneak up on the slug from the side, and try to wrangle it by catching its protruding eyeballs in the little triangle. They would have to be pretty fast, because slugs can retract their eyeballs for protection. So maybe if they got on either sides of it and each held one of the big sticks, and then once they get the stalk of the slug's eye into the corner of the two big sticks, they can run towards each other and join the sticks so that the stalk of the slug eye is squeezed and passes through the small triangle. The triangle should be smaller than the eye of the slug so that the eye won't be able to retract. Now, if the sticks are good and long, they'll have enough distance between them and the slug to remain safe, and the slug will be forced to follow them around because it doesn't want to have its eyes pulled.
[Answer]
**Scare the slug.**
Some slugs have a shell in wich they hide when in danger. Grab a few cat sized slugs, put them in a bag made of one of the heroes shirts and get them where you want.
While hiding the wouldn't produce their slime, since it's use is for locomotion. Keep shaking the bag to keep them inside their shell.
A horse sized slug and his surroundings would stay at constant state of inmolation. Capture him would need alot more resources.
[Answer]
Grab a forked branch.
Put a baby slug on top.
Carry like a torch. Watch for falling slim.
If the slug fall...take it again.
You can use your unlimited torch to travel by night too.
[Answer]
Lure it to a cliff near their destination using fruit. Then create a landslide to bury it. If there is no cliff near their destination, lure it to the destination, then drop small rocks on it from a tree.
Try to push bigger rocks to pin the slug under them. Further transportation of the slug may be too difficult.
] |
[Question]
[
A mainstay of science fiction games is the idea that infantry can be deployed from space based platforms to act as some component of a QRF, or as a replacement for paratroopers. But how feasible is this in real life, disregarding treaties that prohibit the militarization of space?
**Assumptions :**
We are in the not so far future, and humanity has developed a space based platform using current or near future tech that is able to sustain life for an extended amount of time. This platform has artificial gravity and a life support system that can operate indefinitely, but it is dependent on the Earth for some maintenance supplies and food.
**Questions :**
How would these infantry units be deployed in the correct area? I'm thinking that either the re-entry vehicle has to have some type of guidance and boosters to get to the landing zone, or the space platform itself has to re-position.
How quickly can these men be on the ground? Using reasonable advances in technology, can this platform really offer a faster response time than a network of paratroopers stationed around the world (current US capabilities).
If this method of deployment has a tactical value and is more effective than other means of troop deployment, then is it even remotely cost effective? Space vehicles are expensive, making reentry vehicles are also expensive. The answer to this would determine whether this tech gets handed out to a battalion sized group of space marines, or whether it only goes to the space Navy Seals.
[Answer]
It's technically viable, but horribly expensive. It's also not subtle.
Unless launching was a **lot** cheaper you would need a ridiculous amount of resources to keep an army in space. You then get problems with them atrophying unless you can also provide them with training missions and simulated gravity.
So no army then, how about a small special forces group?
Once the cost problems are overcome the actual re-entry process is very obvious. We're talking balls of fire in the sky and sonic booms. They are not going to be subtle at all. Not great for special forces.
The great ball of fire is also a perfect target for defenders to use to pinpoint the soldiers as they come in, but trying to decelerate by any other means would be incredibly expensive in fuel or very slow, or both.
A vehicle shaped for re-entry is also not well shaped for flying in regular conditions, you would have limited maneuvering ability. In fact the most likely scenario is a drop pod that after re-entry the military forces bail out of and then use parachutes (possibly HALO) to close in on the target.
So you're expensive, noisy, obvious and vulnerable. Not a great combination. The one thing you do have going for you is speed. You would orbit the planet 15 times every day which means you could deploy to any location within a few hours.
[Answer]
Military commanders tend to be reluctant to deploy troops to areas from which they can't be recovered if things go wrong -- even paratroops landing behind enemy lines have lines of retreat mapped out as contingencies. So you can't in general deploy troops *from* space unless you can also recover them back into space. And that is a *much harder problem* -- it's certainly not feasible with contemporary technology, or anything we expect to develop this century.
[Answer]
I think that this method, if it becomes technically feasible, would only be used to insert very highly trained special forces type of teams behind enemy lines, and not for massive invasions, or assaults.
***Reason 1: sending people to space is expensive***.
It requires a lot of fuel. It requires some very expensive to build/maintain technology. It requires special training. Sending thousands of troops and their gear up there would be cripplingly expensive for any combination of countries you care to name.
***Reason 2: too easy to defend against***
If I'm the leader of a regime unfriendly to the one who runs this orbital platform, and I know that they are planning to drop 10 000 space marines on me I would make certain to either:
* Target your orbital base with all sorts of weapons (such as launching a fake satellite which is actually full of missiles, or mines into orbit)
or
* To invest very heavily in the sort of Anti-Air (AA) tech that will shoot your drop pods / orbital reentry vehicles out of the sky.
***Most likely both.***
**Conclusion**
Deploying your troops to the right area is actually the easiest part of this venture, and possible even using today's technology.
The problems are ***costs***, and the fact that your base/reentry vehicles are ***very vulnerable***
[Answer]
First question: Maneuver the reentry vehicle, not the station.
* The reentry vehicle will be smaller, so it requires a lower total amount of fuel.
* You can use aerodynamic control for part of the maneuvering. This is impossible if the station is supposed to stay in orbit.
Second question: Depending on the number of stations, an hour to several hours. This is faster than a global deployment with subsonic transport planes.
* With a station in LEO, a global reach would require either lots of delta-V or a large number of separate stations. Then you take the one with the best position.
* For reaction times, look at proposed designs for orbital bombardment systems. A soft landing will be slower, but not much.
* Current airborne forces have to account for a delay because the troops don't sit in or next to their planes. The spaceborne forces can't be away on leave.
Third question: Not even remotely cost-effective with current technology.
* "Space SEALs" are right out. The landing will be impossible to hide.
More comments:
* Human health deteriorates in zero-G. The troops won't be fit when they arrive.
* The space troops would have to go to orbit with all their gear and all their specialists. It will be difficult to add interpreters, drug-sniffing dogs, etc. on short notice.
* Troops can be regionally based and trained, e.g. with the US CENTCOM for the Middle East and surrounding areas. A force in orbit would have to be global.
[Answer]
As the other answers have pointed out, there is a huge cost in resources and energy to get stuff into orbit, and having the right supplies in orbit would be hard to plan for unless you had an orbiting city. However, getting things down from orbit is pretty straightforward, and the speed would be stunning, very probably overcoming most defenses.
If the station is in LEO, it will be orbiting Earth in 90-120 minutes. The reentry 'pod' could be launched at the optimal point in the station's orbit to put it in an orbit to come down on top of the target. When it nears the target, the pod could do a rapid deceleration descent, landing like the SpaceX rockets do. So, station's orbit is 90-120 minutes. If the target is under the station's orbit, there is very little adjustment needed for the pod's orbit. Assuming the pod has infinite orbit adjustment energy, the pod would need at most .25 orbit to reach the destination (15-20 minutes). Reentry from 7.8 km/s at a steady 4g's would take 200 seconds. So, in a worst case scenario, it would take 144 minutes to hit the ground, and in a best case (directly under the orbital path right now) it would take 4 minutes.
Targeting could land on a small target very easily. SpaceX and the Martian landers have shown how getting a rocket to a 100m landing area is very doable.
Defending against an object moving at ballistic speeds is really hard. AA systems would have a few minutes to detect the incoming pod, target, and fire at something travelling at 17,000 mph and decelerating at 87 mph per second. The landing pod would begin firing 780km away from the target and 200 seconds later would land. A precursor to the marines landing could be space rockets or bombs. They wouldn't need to worry about human survivability so they would not need to decelerate, just change directions. High explosive needles similar to bunker buster bombs could be released from the pod before or during reentry and would strike anywhere from 100 seconds (if released from pod as the pod starts decelerating) to immediately before the pod.
Decelerating faster than 4g would allow faster re-entry and greater surprise, but at some point tech to protect human passengers would be necessary. The space shuttle experienced 3g in descent, the Soyuz can reach 15g. Drones or weapons would be able to re-enter much faster, and would not necessarily need protection during re-entry, allowing more useable mass (1000kg landing pod that is a missile = 1000 kg of ordinance, drones with shielding might be 600kg of ordinance and 400kg shielding, 1000kg human pod might carry 4 humans, 300kg, plus 100kg of ordinance).
Compared to a space-deployed bomb, cluster-bomb, or drone, humans would be much more expensive and delicate.
[Answer]
## Use nukes instead
No matter how the deployment is done, if this all happens on a single planet then sending couple infantrymen up to space and then down again takes more resources than building and sending down a nuke to the same spot. If you're averse to nukes, then even <https://en.wikipedia.org/wiki/Kinetic_bombardment> can do more damage as the same weight of soldiers during their (probably short) lifetime after being dropped this way with no symmetrical option for retreat. You could utterly destroy huge territories with less energy than you'd need to get a single infantry company up to space and down to a soft (nonfatal) landing - just aim a similar amount of missiles directly at the enemy instead of orbit.
Thus, for all missions that aim to destroy enemy personnel, facilities or equipment (in a major war, this means the vast majority of them) the cheap and efficient way would be to use high-tech weapons, and the rare and expensive approach would be to send a limited number troopers if you need to achieve some special goals - espionage, high-stakes sabotage of something that can't be bombed, capture and/or interrogation of very important people.
[Answer]
You've said near future, but then granted the space platform artificial gravity. That implies that in the near future, we get a much better grip on the nature of gravity and how to manipulate it.
With a low-energy consuming, solid state anti-gravity available, war becomes much more three dimensional. You wont just be fighting on the ground. You'll be fighting in the clouds and in low orbit.
The spectrum of options for offense and defense expand exponentially, lending a whole new definition to the idea of higher ground. If projectile weapons are still the norm, the warrior with a few miles of height advantage is safe while his enemy is not.
Your space platforms will be equivalent to modern day battleships or carriers. Their movement into orbit over an area will be not only a military tactic but also have political weight. With that in mind, subtlety is not part of the goal. When you finally deploy thousands of troops into descent over an enemy capital, you want them to burn through the sky like falling stars, their ablative armor glowing brilliantly as the swoop down upon a terrified enemy.
[Answer]
In some science fiction it make more sense because troops arrived from other planet, so they need to get down somehow.
For Earth -> Earth in near future it is extremely expensive, not subtle but it is faster than deploying from home (Other answers cower this).
Speed wise - it can be faster or slower than predeployed troops, depends how close to target area troops are. But if you need to send them anywhere and can't have them everywhere it is faster.
Unsubtle approach is still problem. You can limit yourself to areas without AA and accept jumping on prepared enemy/to areas cleared by orbital bombardment (can solve part of AA problem too), or you can make it more subtle.
Instead of jumping from edge of space, use reentry vehicle capable of aerodynamic flight, enter somewhere else slow down to subsonic speed and fly to target area and perform normal paradrop. But such vehicle itself would be extremely expensive itself and bringing it to orbit even more.
Maybe ^^ could be modified by dropping in Star ship troopes-esque drop pods and gliding on squirrel suits. Against long range AA it would be same as dropping directly on target, but if enemy don't have it or its dealt with somehow (counter measures/bombardment) it can achieve tactical surprise (enemy knows you are coming, but don't know where, unless they know that THEY must be target).
[Answer]
# Very Feasible
The entire premise of SpaceX is that launch costs can be reduced by 10-100x by building reusable rockets (believe it or not, the fuel is actually a minor cost of rocket launches). We do not have artificial gravity space stations yet, but there are no obvious physical barriers to doing so (mostly engineering and cost barriers).
# Why
The problem with jets is that we have a very mature set of weapons systems designed to defeat them, from SAMs to interceptor aircraft. And transports are almost never designed to be very fast, because they are almost always used after air superiority has been achieved. Rather, they are designed to be flexible, so they can deliver troops to inhospitable terrain (c.f. Osprey, Chinook, etc.).
Right now, the only weapons systems we have for anti-space defense are ICBM interceptor batteries, which are mostly untested and probably unreliable. Most tests of such systems fail to reach the target or fail to destroy the target. An orbital delivery vehicle would presumably be armored if there were credible defenses which could attack it. Combined with thrusters for evasive maneuvers, such a vehicle should be extremely hard to hit.
# Where
If you look at the placement of AA defenses, they are situated on the borders of countries and around high-value targets. Space offers a border with the entire surface area of the country. You can't blanket all of China or Russia with AA batteries. But clearly, an orbital drop would be a good choice away from conventional AA defenses.
# Who
Obviously, you wouldn't use an infantry drop to shoot a thug or blow up a building. You would use it for target extraction or minimal collateral damage or to reach targets which are hardened against other kinds of attacks (like deep underground facilities).
# Logistics
In addition to having multiple space barracks, you could rotate your marines/Spec Ops teams so they don't spend too much time in space (where they are exposed to a lot more radiation than on the ground), say, every 3 months. And obviously, you would not just put average grunts in space. You would want highly trained fighters, at the least, and possibly your best troops, if that becomes the most effective way to deliver them to the battlefield in the future.
# Limitations
Although an orbital drop lacks subtlety, what it gains is logistical speed. It would be easy to drop into an area which does not have ready defenders, and gain a significant time advantage against a less protected target. Of course, dropping into an area with a lot of defenders is probably a very poor strategy. Even then, the battlefield can be prepped via kinetic bombardment (though defeating air forces would be harder from space, unless you also have energy weapons).
If you consider how long it took to get F-16s on station on 9/11, it is easy to see how soft the interior of most countries is. That was just a few jets. Imagine trying to mobilize a squadron against an orbital drop. It would be very difficult to get them prepped and ready in time to meet the space marines, even if you knew where they were going to land 30 minutes in advance. And if they were snake eaters, then they could land well away from the intended target and infiltrate the countryside, making it extremely difficult to find them.
My guess is that space will be militarized with marines just as soon as countries can afford it and have a good reason to do so.
[Answer]
**Stationing infantry in space**
* As has already been pointed it would be **very expensive**.
* The vehicle to get them back to earth would be very **easy to shoot down**, due to the issues of re-entry that Tim B explained.
* The troops will not be able to exit back to space, so will be on a **one way mission** or **have another exit route planned**.
* The R&D costs will be very high.
**Supersonic “transport” aircraft**
* Given the same R&D spending, I expect that a supersonic “transport” aircraft that is deployable from an aircraft carrier would be cheaper to developer.
* I expect that operating a few aircraft carriers along with supersonic “transport” aircraft would be a lot cheaper then basing the troops in space.
* To get a response time of a few hours to anywhere in the world not need many such setups.
* As the mission is one way or has anther exit route, parachutes can be used to get the troops from the supersonic “transport” to the ground.
* I also expect that entry vehicle could be lunched from the supersonic “transport” aircraft if that was considered to give an advantage.
**So for must less cost than deploying infantry from space, you can set a system that gives all of the advantages with less problems, along with the world wide quick deployment.**
[Answer]
Getting down from orbit is not about the distance - it is just 100 - 200 km high. It is about slowing down from orbital speed of about **8 km per second** which is about 28 times the speed of sound.
In obligatory [XKCD explainer](https://what-if.xkcd.com/58/) **space is not far - space is FAST**.
[Answer]
The ISS orbits at 400 km high. Problem is, in order to stay in orbit you have to really fast, so the time required to land is really the time required to break to survivable speeds. This is done with air breaking because [it's the only cost effective option](https://what-if.xkcd.com/58/). It takes a lot of time. The IIS moves at 7.66 km/s.
Next problem is that the space marines are zipping around the earth in orbit. Making a considerable change to a given orbit takes time, so If you orbit the equator you may need to add a few extra hours depending on where you want to deploy.
At an ISS-like orbit, it takes them 90 minutes to go around the earth once, so if you need rapid deployment and you just missed the window, you now have to wait 90 minutes.
All in all, even with 4 or 5 different space barracks, your average response time would be somewhere around 2 hours.
Compare this with a supersonic delivery system, lets say something based on blackbird technology (3500km/h). If we include acceleration and deceleration, it should easily beat response times of orbital drops anywhere within 3000 km of its base. And the response time is predictable, because it's based on distance, while the space marines zipping along in orbit really make timing difficult for everyone else. Military Commanders always prefer predictable, because there are already more than enough other unpredictables they have to deal with.
[Answer]
It's been mentioned a couple times, but I think that the use of hypersonic transport planes would be more viable than deploying troops from a space station. The space station itself would make a decent platform for kinetic bombardment, but a major problem is that as soon as one country developed a militarized space platform and a way to put soldiers in it consistently, every single country with the capabilities to do so would immediately begin working on how to shoot that platform down. It also would be difficult to counter new anti-space platform threats because the space station is in space and thus it would be (possibly prohibitively) expensive to upgrade a station's offensive and defensive capabilities. It's also worth noting that international organizations such as the U.N., as well as geopolitical rivals, would fiercely denounce such a space station. In extreme cases, a nation may even go to war preventatively to avoid being permanently outmatched when the space station is armed and fully operational...
Recently, the U.S. military tested an unmanned aircraft that flew at Mach 20 ( 15,345.3 mph) for three minutes in a stable and controlled manner. Major military powers around the world are also placing some focus on developing hypersonic missiles, so we see that already, the use of hypersonic speeds for military purposes is gaining momentum.
Fast forward a few decades, and it's conceivable that we will have developed some kind of effective hypersonic aircraft for military purposes. Put an advanced targeting system, an electronic warfare suite, a railgun, a laser, and maybe a couple missiles on it, and then stuff a platoon or a light infantry company into the cargo bay, and a Mach 20-capable aircraft (or greater) could cover the circumference of the earth and deploy its human cargo via parachutes, pods, whatever your imagination can come up with, very quickly. Hypersonic military aircraft would likely be significantly less destabilizing to the international order than a space station that poses significant threats to other nations.
You could also time your orbital space station to launch a kinetic bombardment on a target that impacts very shortly before the airborne soldiers leave their hypersonic ship, which would likely destroy and/or scare the crap out of any military force present.
] |
[Question]
[
Picture, in a near future, that we build cities vertically rather than horizontally. Need a new city block? Add another few floors. Disregard for the moment any physical construction problems this may present.
My question pertains to the reason(s) for building such a city. Why would we do it? It was suggested on [this question](https://worldbuilding.stackexchange.com/questions/25322/vertical-city-effects-on-climate) that the reason could be expanding population, but I would also like to see what other people might be able to suggest.
*Note: It is important that you don't think of this as a city of skyscrapers. Everything is in the towers. As I used for an example above, city blocks would literally be a few more levels. Regular urban houses would be just another part of the massive towers.*
EDIT: I have marked Vincent's reply as the answer. However, for anyone else who might have this question, I also found Peteris' [answer](https://worldbuilding.stackexchange.com/a/25477/6620) and Joe Bloggs' [answer](https://worldbuilding.stackexchange.com/a/25437/6620) to be very helpful.
[Answer]
We are already doing it, all around the world.
* Lack of space: Population and lack of available space drive the price
of the land to very high levels. Other things like speculation also
increase the prices but it's not usually a long lasting trend.
People want to live near the center of the city, not 100km away. The
demand is very high but the land is limited. Well, maybe the pressure
would be smaller if commuting took less time. Having better transit
systems will lead to the creation of an urban sprawl. Then, we have
another problem.
* Lack of space 2: It's not a good thing to cover the whole planet of bungalows. We need to grow food, we need parks and natural forests. Put it simply, we need to have a natural environment and not just concrete. Many cities have laws against building in some areas for environmental reasons (preserving the wetlands) or sometimes for historical reasons. Some rural areas are protected because they are part of our patrimony.
Therefore, although it's not always effective because of corruption,
we have an incentive to limit the growth of our cities. Cities
continues to grow because the world population is still increasing
and because the urbanization is not finished. In developed countries,
people are leaving the rural regions to live in the cities (That is
the case in Canada at least).
So these laws are limiting the available space to build, increasing the need to expand the cities vertically instead of horizontally.
[Answer]
## Why *don't* we do it ?
An useful way to explore why and how we might start doing something is to look at the reasons why we aren't doing it (or not doing it as much) right now.
Why don't we routinely expand existing blocks upwards if we want more apartments or office space?
## Nonextensible buildings
Current buildings are generally built to be (almost) as tall as their infrastructure will allow. Sometimes they get extended to add some extra space above, but only to a very limited amount - simply adding a bunch of extra floors will risk a structural collapse, so it's not done and also prohibited by construction regulating authorities. If people want a taller building, current practice involves demolishing the current building and starting again from the foundations.
If you implement a technology that allows to *extend existing buildings* without extending the load-bearing structures, then it might be an entirely different result, and the places which are currently very dense and with extreme real estate costs (e.g. Manhattan) may quickly become something like your proposed tower cities just because they suddenly can. The real estate owners are limited by available land and by existing investments - with sky-high real estate prices you still won't rip down a 100 story building just to make a 105 story building; but if you had the ability, then just building the 5 extra stories would happen whenever demand justified the construction costs.
## 3D Real estate rights
Currently, there is no legal way to build something on top of another building without the consent of whoever owns the building below. All land plots generally have a specific owner, who then control the construction in a 2D plot of land, and everything above it. This means that if I want to "join" a city, my only options are to either to move in with people already there or to build a new house *next to it horizontally*. On the other hand, if real estate legislation suddenly managed *3D* plots of space, then it would suddenly have lots of free available 'plots of land' for housing near the desired locations. Sure, it requires lots of tech, but with widespread flying cars, a location with 5 minute vertical commute would be much more desireable than a 50 minute horizontal commute.
Tech would allow existing real estate owners to capitalize on their monopoly on a desireable spot even more; but 3d real estate rights could enable a massive resettlement to currently empty space, if they are distributed in a way that actually enables most people to build their houses there.
[Answer]
Building up when you still have the capability to build outwards is resource intensive and wasteful. Not only do you have to consider the initial outlay, but you also have to manage resource movement and logistics for the entire tower. This is a nontrivial problem. Just look at the [Burj Khalifa's plumbing](https://en.wikipedia.org/wiki/Burj_Khalifa#Plumbing_systems) and work out how much effort it takes to pump water that high.
If we're discounting high population density as a reason for doing this the only thing I can think of is to show off. Building a high city with amazing views and keeping swathes of unspoilt countryside around is a pretty powerful status symbol for the country that can do it, but it's fundamentally flawed in an economic sense.
Just for fun though: lets look at some potential reasons and why they aren't actually that good as justifications:
**Spaceport access:** Taller city = higher spaceport = easier to get to space, right? Nope. Not only do you still have to get the components/people/fuel up the skyscraper city in the first place, the height difference is only going to go a tiny way towards the energy needs for getting to space and, more importantly, getting up to orbital velocities
**Reducing commute times:** More compact city = shorter commute as you don't have to go as far, right? Nope. The elevator requirements for skyscrapers can be [complex](https://en.wikipedia.org/wiki/Skyscraper_design_and_construction#The_elevator_conundrum) and might lead to people having to cross a whole floor to get to an elevator to take them up to the floor they need to be on to cross back across the floor to get to work.. *phew*
**Efficiency:** A'la Asimov's [Caves of Steel](https://en.wikipedia.org/wiki/The_Caves_of_Steel) series, it might seem to make sense to condense everything so you can process everything centrally and in the same way. Again: this doesn't work in reality, as the logistical concerns begin to outweigh any potential gains very quickly
**Moving cities:** This seems reasonable at first. Despite the fact that it essentially comes back to a question of high population density, it seems to make sense to put lots of floors on your moving city, however: If the city is ground based you have to worry about the centre of gravity and wind concerns, so it makes more sense to make a dome shaped or zigguratesque city (Similar to [Mortal Engines](https://en.wikipedia.org/wiki/Mortal_Engines)). If you have an airborne city you want to spread the load as much as possible to get as many engines/zeppelins as you can, so a flatter city works better there. If you're in the ocean a decent depth of keel could improve the cities stability, but only if it's also strong enough to take the increased pressure on the lower levels and also the stresses involved in dealing with waves (I think this was a plot point about a floating hotel in a Dirk Pitt novel, but I can't remember which..). Finally: Spaceborne cities would be best off as spheres, even if you're accelerating the whole thing it's the best shape to reduce the various stresses while flying and also turning
**Population control:** Keep the populace close and in one building and you can lock them down. You also lock yourself in with them, and if a crazy cult decides to set fire to the lower floors you're utterly boned.
Essentially: The only reason to build an upward city that makes sense is if your population density is going up. This might be because of an increase in population, restrictions on where people can build, large draw for people to be near the city centre or [reduction in available city size](http://www.telegraph.co.uk/news/earth/earthnews/3349758/Evacuation-plans-needed-due-to-coastal-erosion-says-Environment-Agency.html). Or if you want to brag to all the pretty girls about how big your municipality is.
[Answer]
Thinking of sci-fi, one could build vertical cities to make them fit in a spacecraft. A reason can be aerodynamism. Another reason can be to reproduce some gravity (to turn over one axe at appropriate speed).
By extension, the reason could be the will to move the building.
[Answer]
**Build up to save the planet**. Wherever humans go, they tend to spread out and consume the surrounding landscape with severe impacts on the local flora and fauna. Instead of requiring reduced impact from farming or logging, a society may choose to compress the population into the urban centers while vacating rural and suburban communities to let nature recuperate.
Moving the rural and suburban populations into urban areas requires roughly double the living space as cities presently offer. If the land area used by present urban areas is capped and no expansion is possible then the only way to house more people is to go up (or down but the OP didn't ask about building into the earth).
Cloak each new tower in hanging gardens and solar panels to reduce food and energy consumption from outside the tower.
Building that much housing, office, food growth and manufacturing space is a monumental undertaking that will take decades to achieve.
[Answer]
To reduce CO2 emissions. It is already [recommended](http://www.c2es.org/docUploads/Buildings_FINAL.pdf) to build high-density, mixed-use buildings that can decrease transportation needs and allow for big integrated heating-cooling systems. These benefits of medium-height, high-density don't go away when building even taller and denser if horizontal travel between the towers becomes possible.
Many technologies with the purpose of reducing CO2 emissions have impact on the ideal shape of our cities and a green future could probably go both horizontal or vertical. If immobile expensive solutions such as [deep water source cooling](https://en.wikipedia.org/wiki/Deep_water_source_cooling) catches on, it would draw cities in the vertical direction.
[Answer]
**In the near dystopian future:** Fossil fuels have become scarce, this sharply increases transportation costs. Coupled with diminishing global wages and harsher climates, people around the world give up the dream of owning land - much of which has become dry and barren - and begin to concentrate in large, sturdy towers near fresh water sources where goods and services are more easily accessible.
**In the near utopian future:** Entrepreneurial visionaries devise low-cost, eco-friendly [pre-fabbed skyscrapers](http://www.wired.com/2012/09/broad-sustainable-building-instant-skyscraper/) that look beautiful and offer luxurious views to those who could not afford them before. Wholly self-contained, expandable "town-in-a-box" towers begin popping up in smaller cities and even rural areas, offering a trendy new low-maintenance lifestyle to a generation disenchanted with the burden of home ownership. Empty streets and vacant lots are converted to farm or green energy production, parks, bike paths or simply returned to the wild.
[Answer]
One thing the other answers miss is: pride.
Building large, tall skyscrapers is very much about bragging. The pyramids weren't built for practical purposes. They were built as status symbols...as are most of the worlds 'tallest' buildings.
Tall buildings are used as personal symbols (Rockefeller center), business symbols (Transamerica Building--later a symbol used by the city), and City symbols (1 World Trade Center).
[Answer]
**Because It's Cheap**
Since we're disregarding the physical construction issues...
Land is expensive. Land in cities can be exponentially more expensive. Think about the million-dollar-a-year New York apartments you hear about. Cities have to pay and manage land as well as individuals, so a small city would be incentivized to build up instead of outwards since this is usually done by area.
Now obviously there's an economic relationship here - if you can build higher, land becomes less valuable. But certainly you would see higher construction than we currently make, at least until the point where the cost of going even higher balances out the value of the location.
[Answer]
Looking into Paolo Soleri's works on [arcologies](https://en.wikipedia.org/wiki/Arcology) might be of interest to you. He conceived of the idea of a self-contained city-in-a-building in the 1970's or thereabout. His idea was to provide a small-footprint city in places that might be otherwise unusable or uninhabitable.
[Answer]
The most important reason would be to shorten distances. In a tall city you can fit a lot more room within walking distance.
@JonBloggs lists a lot of excellent reasons *not* to do this, one of which is that elevator systems for tall buildings are complex and difficult.
This is the result of everybody having to go to ground level to get anywhere. If you build exits and transportation paths at multiple heights this will be improved. In addition to the street net, you will have connections at, say, every 25 stories. Both pedestrian and motorized. With ramps leading up and down too. Finding the right bus to where you want to go would need computer assistance.
People living low down will not get much sunlight and this will **NOT** be popular. Expect resentment. If you have cheap power, you can set up fake sunlamps.
Fire will be a **serious** problem. No wood allowed. Paper severely restricted. Plastics? Call the cops!
We are already building tall. In the most crowded cities, buildings are as tall as we can make them (or could, when they were new) This is not going to end.
[Edit add]
Oh, I almost forgot: Aqueducts! Put the water supply at the level of the tallest buildings, makes plumbing so much easier.
[Answer]
Since you tagged it with "near-future" this might not be a good answer but if you were willing to consider the distant future... For some reason, you might want to move an entire city... (e.g. a proliferation of natural disasters, constantly moving war-zones / fronts / borders, the population collectively wants a holiday in the sun, etc.)
A lot more practical if the entire city is contained in one building (and you have the technology to move a very large building)
[Answer]
There are already a lot of good answers here so I hope my small addition will be valuable.
There are a few pre-planned & designed cities engineered for advancement in technology and often decreased environmental impact.
[Masdar City](https://en.wikipedia.org/wiki/Masdar_City) is the one that, to the best of my understanding, comes closest to the concept I want to present, (skip down to the Architecture section & skim a bit).
To add to the Masdar City link I would like to direct your attention to the design of termite mounds. I think it's valuable to consider both the [real design value of termite mounds](http://news.harvard.edu/gazette/story/2010/10/termites-as-architects/) as well as the [generally accepted & long standing belief of their value](http://nautil.us/issue/8/home/the-termite-and-the-architect) (as both could be accomplished with a large and possibly segmented tower design).
**Concept:**
The basic concept is to make a city that is self sustaining.
The value of my referenced material is that it has been proven in Masdar City & the Zimbabwae sky scraper that it is possible, through correct design, to passively control the environmental temperatures of a coherently designed structure.
In addition the more correct understanding of the design of a termite mound proves that ventalation & moisture control can also be accomplished passively.
The requirement of all of the above is, effectively, a single integrated structure, therefore supporting the design choice of a single tower like structure.
Let me add one additonal thought, the value of this might be increased in hot arid lands/planets.
(though I haven't put much thought to it, there's a chance this might be true of cold environments/planets as well... )
] |
[Question]
[
In a nutshell, I've an 8-fingered bat-like humanoid (let's call them AX) and a 10-fingered 'standard humanoid' species (let's call them BX) sharing a planet.
AX was the first to develop things such as agriculture and animal keeping. They were the first to trade as well, and thanks to being able to cover vast distances by wing they worked as traders for millennia. With all this in mind I'd expect them to have been the first ones to decide on numbers, and have decent amount of influence on BX when it comes to counting, etc.
However, they only have four fingers per hand and I don't know how that'd affect things. It makes me wonder whether they'd be more likely to gravitate towards a base 8/9 (fingers/phalanges) counting system, for example? Or even a base 36? Would it be likely they'd end up coming up with a base 12 regardless?
I don't want to handwave anything or make uneducated decisions, so I'm hoping someone more educated than myself could help me out.
* edit: I've clearly made a mistake in not describing AX in more detail. [[They're bat-*like* humanoids]](https://i.stack.imgur.com/DtHJq.png), are 2.5m tall and capable of flying with 60kg cargo... hence why I'd thought they could make ok traders. But these are a fairly new creation so I don't mind changing things that don't make sense.
[Answer]
They could use base 8 without any handwaving, and it would be quite interesting. There is more to it than you may think, though.
We humans in the real world tend to think that everyone uses base 10 because that's just natural, or because it comes with having ten fingers. And Tom Lehrer (famous math teacher and musician) once said that base 8 is just like base 10, if you are missing two fingers.
In practice, though, base 10 stuck more for being practical than for being natural. It makes things easy for the bulk of the calculations that a regular person will have to do during their lives.
But there are so many things that are easier with radixes other than 10! That's why computers work with a binary base. IT professionals and computer scientists will often use base 16 in their jobs, and once you get used to it you can do mental and napkin calculations in hexadecimal.
Also notice that the usage of alternative radixes is not something that came up with recent technology. See Wikipedia's entry on vigesimal for a plethora of old and ancient mesoamerican, african and european cultures that used base 20. [And the traditional weight measures of the chinese is built on base 16 and used to this day and age](https://en.wikipedia.org/wiki/Chinese_units_of_measurement).
---
Back to your species A and B. They may each use their own numeric base, and the way they convert things from one system to another would feel like a simplification of conversions from metric to imperial (and vice versa). This would seem realistic.
But if you think that this adds little to your world and stories, you can write it off and weave your stories so that one numeric base was either imposed by force or selected for practicity. This would open the possibility for interesting stories on how the current system came to be.
All possibilities are equally belieavable and require no hand waving nor suspension of disbelief.
If you want more food for thought, see my answer for [Aliens doing algebra](https://worldbuilding.stackexchange.com/a/52386/21222). It is about how other species may abstract numbers in different ways, and how it would feel for each species to learn each other's algebra.
[Answer]
### Use whatever you want, no hand-waving needed
Historically there is no strong relationship between the number of fingers and the base of the number system used. The Mayans base was 20, the Babylonians base was 60 - factors other than fingers tend to be dominant.
**number of fingers != base of number system**
It has taken the world thousands of years to converge on decimal and metric. There are still many people that say the *base 12*-ish imperial system is better than metric. The English had a non-decimal monetary system till 1971. Roman numerals are still used.
I’m sure if trained from birth humans could easily handle a wide range of bases. I think the limit would end up being human working memory rather than fingers.
If the bat race had a good base 8 system humans would use it for thousands of years without any complaint.
[Answer]
The base one chooses for numbering is purely a convention. A similar convention is used for alphabets.
In case of the alphabet, Phoenicia was the first to develop a versatile system and spread it into the Mediterranean Sea with their commerce. Most of the civilizations born afterwards in that area used then the same alphabet (even I do while I write this answer).
Using an octal numerical system is as good as any other base, and considering they have 8 fingers is the most likely to be chosen.
Regarding other numerical bases, their mathematicians can of course discover them, as we did. They will not be knowingly used by the masses, though. (*there are 10 types of persons: those who understand the binary, and those who don't*)
[Answer]
The idea that water takes the path of least resistance is fundamentally true for everything. No one would count digits/not thumbs, flanges, knuckles, etc. That's too much work. Your bats would develop base-8 and the humanoids would simply deal with it.
But, if you think about it, human counting hasn't always been base-10. We've done odd things for odd reasons. Like hours in a day, or [pre-decimalization British money](http://projectbritain.com/moneyold.htm) and [pieces of eight](https://en.wikipedia.org/wiki/Spanish_dollar).
So, while your batoids would most likely count base-8 and that will thow an amazingly interesting curve ball into the mix. But you need to focus as well on how numbers are used because that will affect things, too. These influences include the whims of kings, religion, practicality, and a host of other non-count-on-my-fingers reasons. Your humanoids can easily accomodate base-8.
But, if you think this is fun... wait until your society needs to leave the gold standard because the good, honest folks have discovered [clipping coins](https://en.wikipedia.org/wiki/Methods_of_coin_debasement) is more valuable than the original coins, themselves!
[Answer]
The Mayans used base twenty, so it is possible that your aliens might use a base like sixteen. That counts fingers and toes (assuming they have the same number of toes as fingers).
They could also go the other way. If you want both races to use the same numbering system, it sounds like both have four limbs. So make it base four. That would probably be an easier system to share than either base eight or base ten. That would help reinforce the idea that the two are interdependent with a long history of working together.
Having them use base eight or base ten would indicate that historically one has dominated the other. So one would adjust to the other.
Having each use their own base would indicate that they are mostly independent of each other.
Another argument in favor of base four would be if they would use their feet to manipulate things rather than hands. Consider that the "hand" of a bat is the wing. Note so good at manipulation. But bats use their feet to grab things. And a typical bat would need to use one foot to maintain its perch. So situations when it could use both feet at once would be rare. Therefore, they might count with just one foot.
[Answer]
Larry Niven's [Kzin](https://en.wikipedia.org/wiki/Kzin) had 3 fingers and a thumb, and counted in base-8. So there is fictional precedence for this.
Here on Earth, the Mayans were not the only people counting in base-20 either. [Traditional English counting systems](https://en.wikipedia.org/wiki/Yan_Tan_Tethera) also used it, evolving independently of other European systems of numbers.
As other answers have said, the AX will develop something appropriate to them. When the BX become numerate, they'll learn to do it the AX way.
[Answer]
## Just counting fingers is too base-ic
Our base 10 number system is theoretically there because we have 10 fingers but for the same reason, that being physical traits, there are (or were) societies that have other counting bases. 20 is a common one to bring up because toes exist but iirc there was a small country or tribe that had a base 24 because that is the number of sections on your fingers (no thumb included) and yet another that was base 18 because they counted up their arm across their shoulder and *then* onto the other hand rather than just using their fingers (fingers, wrist, forearm, upper arm, shoulder, repeat down other side).
With this in mind you can see that just counting the number of fingers is a very base way to count and actually one of the most boring. You can find any number of interesting ways that fit within your story to give them a weird number system or even share the same number system with their more standard humanoid friends. Maybe the bat people came up with base 10 even with 8 fingers because they count like so: 1,2,3,4,wing(5),6,7,8,9,wing(10), which could give them a base 10 system with a naming scheme based off 5s (or even a base 5 number system).
[Answer]
@Renan had a wonderful answer but I believe you could adapt that even further.
**AX-AB Relations**
Assuming that the different species evolved all the way from small cells and upwards, then there was a vast amount of time where neither species communicated in a helpful manner, such as before each species developed complex spoken language. I buy into the developmental argument and think that humans tend to, when left alone, develop a base ten counting system (generally but not always).
Furthermore, as @Renan pointed out, Base 10 is quite useful. If the AX species formed complex society and trade, then it is possible they discovered base 10 on their own and use it for certain fields of work (much like Computer Scientists use base 2 and base 16 today). Furthermore, if they were exposed to human cultures using base 10, then it is quite reasonable to think that they may have adopted it for human-developed projects (say humans got to calculus first or something similar). In the same vein, traders that do business with humans would certainly know base 10 (given humans using it), so they could join mathematicians and educators as AX beings fluent in base 10.
This would work the other way around too. BX/Human merchants, educators, administrators, and translators would have significant use for knowing base 8 or whatever the AX species uses. This co-mingling of numerical systems could be an early path into the growth of mathematics in your universe. Systems used by traders to convert from base 8 to base 10 might be the earliest form of mathematical formula or computational systems, leading to further discoveries and societal progress.
If the AX species is dominant globally or in certain regions, you can bet their number system will also be dominant in these areas. But I think that both number systems could co-exist if you wish. On the other hand, you could use this difference as a wedge to be driven between the species, causing conflict. I love this little world your building!
[Answer]
First not all numerical bases are not equals. Powers of 2 are great in computer world because the basics of all computer is binary: there is some current or not. But for human beings, acceptable bases are ones that can be easily processed, that is where it is easy to multiply and divide by small numbers. 12 is one of these bases because 12 is divisible by 2, 3, and 4. But a non injured human being has five digits on each hand, so divisibility by 5 is important.
Thus, it is not by accident if many civilizations have used at a moment a base 60 system, because it is the smaller number that can be divised by 2, 3, 4 and 5 - BTW you gain divibility by 6. Other common bases were 12 (2, 3, 4, 6) (12 hours on a clock, 12 pence in a shilling in old monetary systems), 20 (2, 4, 5) 20 shillings in a pound, both being divisors of 60. For the other divisors, numbers 6 and below were too small, 15 is not divisible by 2, and 30 while mathematically interesting because is is the smallest number divisible by 3 primes, is rather great and not divisible by 4 when dividing in 4 is a common operation (think of a pie...)
So for a species with 8 fingers, the number 5 is likely to be less important, so the natural bases should be 8, 12 and 24
[Answer]
Beware of the number of digits.
Even if base 2 is really convinient, the number of digits needed to write a number escalate really quickly, this is one reason why we don't use this kind of small base. Base 5 (like on one hand or 4 for your bat-like humanoïd) follow the same logic.
On the other hand, with a base 36, you will need 36 symbols to represent each digits. Our alphabet doesn't have that many symbole, it could be really tricky to calculate with this.
That being said, I don't really know how bats works or how the AX mind could work, but they realistically could develop a setup to uses those radixes or already have a setup to come up with it
] |
[Question]
[
I'd like to have a large underground world. Imagine the "Underdark" which will be familiar with DnD folks. A huge network of large and small caverns connected by winding passageways. The occasional vast underground lake.
I would like for this subterranean world to be populated with wicked denizens. Entire cities of thousands of people (or descendants of renegade elves, dwarves and such from the surface). Plenty of trolls and random monsters, the odd eldritch horror.
There's only one problem... **food**. It takes a lot of provender to supply an underground empire, after all. And on our Earth, the larder is pretty bare in underground ecosystems. I have a few ideas, but need some more.
* Way down in the deepest caverns extremophile bacteria are happily eating away at the rock -- after all, this is how the Downbelow grows. This provides a source of biomass slowly trickling up from beneath.
* There's some kind of critter which is like a cave-salmon. It is born in the caves as a little thing, runs around in the upper world for a few years to fatten up, then along with untold thousands of its kind, races back down to the caves to spawn. Grisly wars are fought over control of the best routes taken by cave-salmon.
* Um. Well. I hesitate to bring this up... There is a steady trickle of adventurer types from above, and ... um ... well, "meat's meat", y'know.
I'm not sure if these ideas are enough to fuel an overall population of let's say 100,000 human equivalent. So help me out here, my monsters are starving!
[Answer]
d\_hippo made a good point with **"Our foodchain is based on photosynthesis, which requires light."**
Your caverns would not be a closed system of caverns. Somewhere it will connect to the outside world, and that's where your supply of energy come from.
1. Create an intermediary species that lurks just several meters away from the cave opening. This beast will **capture animals that stray too near** to the cave opening.
2. Create a species that **graze on the mosses** that grow in the opening of caves.
Expanding the idea, get yourself one, or two turtles.
Well, not really turtles. Anything designed to grow plants and mosses on its back is fine. Or [slugs](https://worldbuilding.stackexchange.com/questions/86155/is-an-organism-with-both-animal-like-traits-and-plant-like-traits-scientifically).
3. Now you can create another species that **preys on the first two species**, or make the inhabitants **harvest these two species directly**.
You can even make them **raise them as cattle.** At no cost, because you can just make the pen open-ended to the outside world without worrying them to run away (they're underground creatures).
4. As mentioned in 1st point, there will be strays coming in to the cave. **Bugs, bats, fishes.** Your underground inhabitants *can't be **picky***, food is scarce after all.
This actually makes a good plot point why the Underdark inhabitants are viewed as ruthless and disgusting: *they need to survive in a place where resources are **scarce**.* Competition is not just a competition, it's a death-or-life competition. Only *limited denizens can occasionally show up on the surface.* And that's make my last point:
5. Some of those that can go to the outside world (dwarfs and genomes?) can buy supplies - for themselves - and robbed in the way back home.
**Update:** Olga is making [a good point](https://worldbuilding.stackexchange.com/questions/90158/how-can-i-get-enough-food-into-my-underground-empire/90190#comment267377_90190) about the diet lacking nutrients but protein. Here is my interpretation:
There are races that are naturally attuned to the Underdark, and there are Surface Dwellers who are exiled into the Underdark. Both have adapted to the diet, but those recently joined them obviously haven't. Those who are not satisfied with the gourmet can **harvest plants and herbs and hunt** just outside the cave. Of course, that will be temporary, until they accept their fate, or they accept their "fate".
Additionally, they may have a "mushroom farm" on corpses (it's better than eating the cadaver), that stores energy as carbohydrate. However, mushroom is usually low-carb, so you might have to create a new species for that. Animals with plants on their back will also work too!
[Answer]
You can mix and match any of the following:
# Scientifically Possible Options
You need a steady flow of either **biomass** or usable **energy** to feed you underpeople. These may come from:
1. **Surface excursions** - the sentient denizens bring food from the surface by raids or trade. Some cave creatures hunt or graze outside but return to the caves for mating/dwelling/hibernating/raising their young etc. Note that this doesn't have to be a single creature making its way from the deepest cave all the way out - it can be a chain, where every "member" brings the food slightly deeper than the previous one, all the way to the deepest caves of the Downbelow.
2. **Food flows in from the surface** - seasonal floods or steady rivers pushing dead material from the surface enable the growth of fungi, which in turn feed your underpeople or some creatures lower in a food chain. Some water bodies may even allow fish and crustaceans to migrate into the caves. (somwhat similar to [ZioByte's answer](https://worldbuilding.stackexchange.com/a/90188/756))
3. **Light shaft "oasis"** - not all the Downbelow is dark - some rare places do receive some sunlight - either directly through deep chasms and fissures, or indirectly, thanks to the reflecting properties of ice, polished stones, or cleverly placed mirrors. Such places can allow moss and lichen to grow and support a small food chain.
4. **Thermosynthesis** - (as [Glurth suggested](https://worldbuilding.stackexchange.com/a/90187/756)) there are ecosystems on earth based on the heat of deep-sea thermal vents. You may have something similar in deep under water lakes, or even geothermal shafts/volcanic activity as the energy source to support a food chain.
# But wait, this is a fantasy setting, isn't it?
Here things can go increasingly creative/crazy - starting with other sources of energy/biomass to feed the Downbelow denizens or support food chains the subside on, and ending with truly fantastic ideas. Used poorly, this is just a bunch of handwaves circumventing the problem. Used in the right measure, this may add a lot of flavor and wonder to your underworld:
1. **Portals** - these can provide anything from livestock, plants or sunlight even to the deepest places in the Downbelow.
2. **Magic supported cuisine** - some denizens may use magic to grow crops in the dark, duplicate the cattle (or slaves?) so they never run out, or simply conjure creatures for slaughter or magnificent feasts. This magic may come 'out of nothing' or it may be fueled by some resource which *is* available in the Downbelow (mud, gold, sacrificial virgins, works of art, laughter... anything that works for your narrative)
3. **Divine provision and mythical regeneration** - (based on comments by Olga and user54373) Some beings are so powerful that an interaction with them can feed a nation for generations. This may be something simple as manna from the heavens (er, rockceiling?) provided to devoted worshipers, some kind of pact with a force of evil delivering food in return for services or a more dire price. Or even the direct utilization of the fact that some gods and mythical creatures regenerate so well that you can harvest their flesh as a renewable resource - you can have a "meat mine" daily carving into the flesh of [Jörmungandr the World Serpent](https://en.wikipedia.org/wiki/J%C3%B6rmungandr) or a Downbelow equivalent of a punished [Prometheus](https://en.wikipedia.org/wiki/Prometheus#Hesiod.27s_Theogony_and_Works_Of_The_Days).
4. **[Spontaneous generation](https://en.wikipedia.org/wiki/Spontaneous_generation)** - ever wondered why does The Cave of Spiders without Number never run out of spiders? or did you noted that whenever you break a large geode, small silver snakes slither from it? see those dark red mushrooms? they keep growing year after year where a great hero was once slain... You get the idea, in a fantasy setting, the idea that life can emerge from inorganic matter or just spontaneously appear isn't impossible.
5. **Unusual nourishment** - maybe some caves have plants or fungi which feed directly on ambient magic. Maybe some of the denizens are semi-elemental creatures that feed on crystals or metals rather than organic materials, or maybe you have creatures that literally feed on fear (but are perfectly safe to eat!).
6. **No nourishment** - and then you have all the fantastic creatures (things?) that just don't feed at all, or at least not as a requirement. They can be golems, undead, elementals, demons, really wired horrors (how does the razor tentacled humongous eyeball even *consume* anything), people under the direct care of a god, and this list can go on and on. Some creatures just don't care about food in a fantastic setting.
[Answer]
Allow me to Quote wikipedia: <https://en.wikipedia.org/wiki/Hydrothermal_vent>
>
> "The water from the hydrothermal vent is rich in dissolved minerals
> and supports a large population of chemoautotrophic bacteria. These
> bacteria use sulfur compounds, particularly hydrogen sulfide, a
> chemical highly toxic to most known organisms, to produce organic
> material through the process of chemosynthesis.
>
>
> The ecosystem so formed is reliant upon the continued existence of the
> hydrothermal vent field as the primary source of energy, which differs
> from most surface life on Earth, which is based on solar energy. "
>
>
>
A large underground sea, heavily populated with such vents could theoretically provide the basis for an entire oceanic food-chain, much like plankton does in Earth’s oceans.
The one problem with this scenario is thermodynamic: the oceans must also be cooled, at the same rate the vents heat it, or it would be boil away! One resolution is to ACTUALLY boil SOME of it (in a single location), and let the steam escape to the surface, while an equal mass of fresh surface water pours down (in a different location) from some arctic surface sea.
[Answer]
You can have an underground "River of Life", which is the underground emissary of a large lake literally choking in [Spirulina](https://en.wikipedia.org/wiki/Spirulina_(dietary_supplement)) algae.
The algae will readily die when taken away from light, but they can boot-start your food chain starting with small fishes, following larger fishes, etc.
Large deposits ashore can feed the luminous fungi described by @d\_hippo and start some vegetal development.
[Answer]
I think you have two options: 1) import all your food; 2) grow your food.
## 1. Import
Ancient Rome or medieval cities can be a good example here. At its peak, the population of Rome was about 1 million people. Obviously, they could not grow their food themselves. So, they were importing almost all of it.
In case of Rome, they had the entire Empire to provide them with grain. You can follow their example and establish a protectorate over the nearby lands and collect tribute in foodstuffs from the surface population. You can design it as a "monster protection fee". To spice things up you can ally trolls and alike with more human-like species in a quest of establishing control over farmers.
Another approach is based on trade (similar to medieval towns and even modern cities). Your underground towns can become centres of free trade where anything can be bought and sold. Your business model should be based on the idea of providing unique goods and services. For example, it can be a place to hire mercenaries, find a rogue mage, or buy unique armour, weapons, and jewellery (elves+dwarves would make a fantastic design team). I would also look into spider silk. If your caves are the only place where it can be produced and made into cloth or armour, you have a monopoly.
With income generated from the trade, your underground city should be able to buy supplies.
## 2. Food production
This can be tricky. A lot depends on available magic and technology. You also need to think about balancing the diet. If biology of your underground dwellers is similar to human you must provide them with sources of dietary fibre, carbohydrates, protein, fats, and micronutrients (vitamins and minerals). Unless it is a dystopian realm where diet related sickness is a feature.
It might be possible to create something like vertical farms. If your underground citizens can make mirrors, they can create an elaborate system of mirrors reflecting sunlight into caves. This would allow growing food on shelves. Hydroponics (water mist in particular) is the best growing method in this setup, but I am not sure if you can do it with pre-industrial technologies.
In addition to vertical farms for vegetables and grain, you should build mushroom farms for a healthier diet. Insects and worms should also be included to provide protein. Small animals like hares can be raised in cages. They are low maintenance and a good source of meat. However, the mean is extremely lean, so you must provide your citizens with some oil or fat to avoid [rabbit starvation](https://www.wikiwand.com/en/Protein_poisoning). If you have access to the surface in a mountainous region, goats can also be an option. Goats are great for meat, milk, wool, and hides.
As @ZioByte suggests, algae pools can be another source of nutrients, especially protein. They still need light and quite bright for rapid growth. However, algae can feed not just fish but also humans, poultry, and livestock. An additional benefit is that some of them can use diluted human urine as a growth substrate. Hence, you can keep your city clean.
Fish ponds stocked with species similar to [tilapia](https://www.wikiwand.com/en/Tilapia) are also a very attractive option. Tilapias grow fast, easily tolerate overcrowdedness, and are very sturdy. While real tilapias are sensitive to water temperature, it might not be the case in your situation.
Pigs would be another great addition to your city. They are omnivorous and can consume almost all food waste produced in the realm. Their excrements can be in turn used to feed algae and shrimp (the latter is done in China).
Throw in some hunting and gathering and your population should be fully covered in terms of dietary needs.
One more thing to consider when it comes to growing food is how centralised the production is. You can have underground farmers or huge government operated factories. Your city might sponsor farming infrastructure (mirrors and irrigation) and then tax farmers (or all citizens) or farmers might be left to their own devices.
Magic makes all of this much easier, especially if your mages can create artificial lights, irrigation systems, and so on. A huge drawback is that they become de facto rulers of your dark realm. Everybody would depend on them for food. Unless they are needed only to set the production up.
A combination of the two approaches would give you the best chances of feeding your population.
[Answer]
The main Problem with food in the Underdark is the missing of light. Our foodchain is based on photosynthesis, which requires light. Because the Underdark is, uhm, dark, you'll have trouble establishing a foodchain, because its basis is missing. So you need to address that problem in some way.
One possible solution would be let your world have strong-glowing bioluminescent fungi. So strong-glowing that they enable photosynthesis. They could be cultivated by underdark denizens, who use them to bring light to their farms. Or they could naturally populate larger caverns, who then become something like an underground oasis. Plants could grow there more easily, herds of herbivorous animals would circle between these oasis and monsters would feed on the herds when they travel through their territory. Maybe some species would develop hibernation, to save energy when prey is scarce.
Since your underdarklings don't seem to be on good terms with the surface anyhow, maybe raiding is an option for those in the upperdark. Raiding farms right after harvest could bring in huge quantities of food. Hunting on the surface could also be an option, but i doubt it's practical to feed large underground populations that way; maybe meat, hunted onthe surface, would be considert an expensive luxury.
**Edit**: As mentioned in the comments, the fungi need a source of energy, too, but I don't see that as a gamebreaker. Fungi don't use photosynthesis themselves, so their energy could come in other ways. They could feed on the stone-eating bacteria mentioned by OP, or on a by-product created by the stone-eating. Or they could feed on organic material from the surface, brought down by water.
[Answer]
Food is a form of **energy**. Therefore, think how the underground ecosystem can gather **energy**. You have to answer two question:
1. Where do/did the **energy** come from ?
2. How the ecosystem use the **energy** ?
3. How the people can increase the efficiency of transform **energy** to their food ?
---
Some suggestion:
**First question:** Where do/did the **energy** come from ?
* It is already there for a long time. Dead bodies -> fossil oil ...
* From surface microbio, wash to the deep by water current (rain water
go down) or in the air.
* From the core of the planet: volcano. (heat is a form of
energy, soil, ...)
* Water current
* Magnetic field
* Sunlight (difficult, but possible when there is the hole to the surface)
* Magic (?!), yes, in fantasy world.
**Second question:** How the ecosystem use the **energy** ?
Food chain: Bigger creature feed on smaller creature, then the food chain go on.
The bottom of food chain (the creature that being eat but not eat others) feed on available energy in the deep empire, or the creature itself come from the surface.
The case of feeding on available energy:
* Some kind of \*\*\*\*synthesis. Replace \*\*\* with photo (if there is sunlight), magnet, heat
* Decompose: fossil oil, coal, any chemical that contain energy.
**Third question:** How the people can increase the efficiency of transforming **energy** to their food ?
* Farming: raise the mass number of creature in the food chain as they prefer. Pick any creature in the food chain, which the citizen can consume their meat or their by-product. Then raise the creature in mass number.
* Generator: It is great if there are nearly-unlimited power source (water currency, magma pool). The generator turn energy to light for photosynthesis (creature take from the surface), heat or magnetic field to use on particular farm for mass production.
] |
[Question]
[
We are currently estimated to be about 0.7 on the Kardashev Scale.
I am interested in the second level of the Kardashev Scale:
>
> **Type II**
>
>
> "A civilization capable of harnessing the energy radiated by its own star (for example, the stage of successful construction of a Dyson
> sphere), with energy consumption at $\approx4\times10^{33}$ erg/sec. Lemarchand
> stated this as "A civilization capable of utilizing and channeling the
> entire radiation output of its star. The energy utilization would then
> be comparable to the luminosity of our Sun, about $4\times10^{33}$ erg/sec
> ($4\times10^{26}$ watts)."
>
>
>
Theoretically, how would a Civilization achieve this level of scientific advancement and what resources would they require to be able to harness the energy of an entire star?
I am imagining something like a Dyson Sphere would require incredible resources to build, so wouldn't such a civilizaton need to have invented some kind of interstellar travel to obtain all the resources required? And if that is the case, would it be better to define a Type 2 Civilization as one that can harness the energy radiated by *a* star, rather than its own?
I am just assuming that in building a Dyson Sphere any planets orbiting that star would be negatively impacted by the building of a Dyson Sphere (Dyson Spheres extend out to the habitable zone of a solar system, where the Civilizations homeworld would be located). So there would be a transitional period where the Dyson Sphere isnt ready yet, but the planet your civilization lives on is being impacted significantly by the partly constructed Dyson Sphere.
Would a Type 2 Kardashev Civilization really build a Dyson Sphere around their own sun? Surely they would do this to another star? And if they would use another star, why does the very definition of a Type 2 Civilization specifically mention a civilization using its own star?
Am I missing something here? Or am I just over thinking this?
[Answer]
My intuition is that they will not.
A Type II civilization would be able to get fusion energy, information, and raw-materials from multiple solar systems; it is capable of evolutionary intervention, interstellar travel, interstellar communication, stellar engineering, terraforming, star cluster-scale influence and can be expected to be so within 1000 to 2000 years from today and last for a few tens of thousands of years.
A Dyson Sphere derives its energy from Solar radiation in a similar way to how it is done today by solar panels but expected to be much more efficient.
My opinion is that a civilization that has mastered interstellar travel must have developed propulsion systems and a dominion over matter and space that are unimaginable today. In terms of comparisons could the Romans have imagined the engineering and energy methods of production or even the sources of energy today, their efficiency, most surely not to a large extent. In the same way I would think that in 2000 years new unimaginable methods could be devised. Who knows, perhaps extracted from the vacuum of space, mini black holes created in laboratory, antimatter produced in sufficient quantities in particle accelerators and other more compact and efficient forms of energy extraction than today even if at optimal efficiency conversion rates. I believe radiation extraction like today's solar energy is not a very efficient energy source as compared to fossil fuels, nuclear fission or renewable sources as its is today and my believe (I am no expert on energy) is that it will be the same in the future.
As a matter of comparison and to illustrate the difficulties of imagining the future Jules Verne the acclaimed writer was one of the best thinkers of technologies of the future and thought of submersibles and flying machines. However in his visions he imagined that personal travelling in late XX century would be done in aerostatic living rooms fully furnished with early XIX acommodations.
So imagining the future seems rather simple but it is extremely complicated as exponential growth in discoveries of different sciences provide paradigm shifts which can not be thought during large temporal scales.
[Answer]
What is missing is parsing the requirement accurately.
Type II definition includes "capable of utilizing and channeling the entire radiation output of its star", and then continues to discuss the energy utilization.
This does not require actually capturing all solar radiation of their star. For example, we could harness the equivalent energy to all incoming solar radiation on our planet, through the use of fossil and atomic fuels. If our energy utilization is comparable, then we reach Type I. In the estimate of our civilization as being .7 - it should be clear that we do not actually capture 70% of all incoming solar radiation - we harness 70% of the equivalent.
If some civilization has some magic energy factory capable of putting out energy comparable to the output of their star, they meet the criteria. The reference to "its star" is just providing a benchmark to measure against.
Dyson spheres are frequently mentioned because they would be a clear identifier of using that much energy - it would be much harder to identify a fusion power plant burning the atmosphere of a Jovian planet, or part of their ocean, as an example of an alternative.
[Answer]
A Dyson sphere is something that would be built over the course of quite a while. It would probably start as a ring around the Sun that just keeps getting bigger as energy needs go up. It would also be using up most if not all of the extra-solar matter in the solar system in order to create this. There would be plenty of habitat area on the pieces in space. the home planet would likely be deconstructed in the process off creating the sphere/swarm so it would have minimal impact on the planets in the system. Even a ring around the sun would have so much more surface area than the sun that 'keeping' the home world around for nostalgia wouldn't be worth the materials Earth represents.
EDT: Went to get some numbers.
Earth volume = $1.08321 \times 10^{12}\, \text{ km}^3$ (whole earth, including water etc.)
Earth orbit distance = $1.49597870 \times10^8\, \text{ km}$
So this means there is about $7.2048 \times10^4\, \text{ km}^3$ of earth for each $\text{km}$ of orbit, so if the earth was rolled out like play dough in its orbit to make a surface $0.5\, \text{ km}$ thick, it would cover a strip about $1.45\times10^4\, \text{ km}$ wide of the sphere to encompass the sun. This is not dealing with all the other matter that would be needed for plants and animals (including humans) to survive. For comparison, the full surface area of an earth-orbit Dyson sphere is $2.81\times10^{17}\, \text{ km}^2$ and the width of our surface is comparable to Jupiter's diameter at $1.4\times10^4\, \text{ km}$.
[Answer]
I imagine these kinds of Dyson spheres very close to the star. This means that if you could use one cubic km of matter for each square km of the sphere, about six earths would be enough to cover the sun. You wouldn't have to travel interstellar distances to get 6 earths of mass.
You can also use a geometric progression to help you out. If one square km section of sphere gets you enough energy over say, 20 years, to collect 2 cubic kms of matter from somewhere in the solar system and fashion them into two more sections of sphere, you could have the whole sphere finished in 800 years.
Also, the nice thing about a Dyson sphere is that you can leave bits of it open. For instance, with half a Dyson sphere, you can cover only the far side of the sun and capture vast amounts of energy without changing our own blue skies.
[Answer]
The one question I haven't seen addressed yet is that of the chaotic effects of moving significant quantities of mass around the solar system. Considering the intractability of the three body problem due to nonlinear effects, determining the long term stability of a Dyson ring or sphere system seems impossible. The best that could be done likely would be constant approximation and correction techniques used to maintain as much stability as possible.
[Answer]
Mankind's yearly energy consumption early 21st century was around $5\times10^{20}J$
Each year, while the sun outputs about $1.2×10^{34}J$ per year, which means we use about 10 femto-suns of power. To Nikolai Kardashev reaching out to the sun seemed like an obvious thing to do. Think about it: you have this immense amount of free energy streaming out into space, and essentially every Joule of it is wasted. You don't have to build a nuclear reactor, you don't have to worry about fuel. All you have to do is reach out and harness it. Since the intensity of the irradiance descreases with the square of the distance, you can maximize your capture and minimize the surface area needed for a particular amount of power generation by placing your generators closer to the source.
```
Solar Irradiance at the Planets
Planet Solar Irradiance, W/m-2
Mean Perihelion Aphelion
Mercury 9116.4 14447.5 6271.1
Venus 2611.0 2646.4 2575.7
Earth 1366.1 1412.5 1321.7
```
There is a vast, vast amount of matter in the Solar system, some of it conveniently outside of the massive gravity wells of the rocky and giant planets, so it's not an insane guess to expect that we'd use Asteroid Belt matter first, then the even larger Oort cloud resources. Obviously we wouldn't just make a Great Leap Forward and become a Type II overnight. We'd first have to reach Type I, defined roughly as making use of the resources of a home planet. If we take the Yearly solar irradiance of Earth, at $5.5×10^{24}J$, we still have a ten-thousand fold growth curve to ascend to even reach Type I. To do a Fermi simplification, let's assume 100% capture efficiency, so if you built solar panels at the Mercury perihelion, **to reach Type I via solar you'd need 12 million sq. km.** of panels, which is in the same order of magnitude as the area of Europe. Might seem like a lot, and it would doubtlessly require far more resources than we can currently even dream about harnessing, but the area of a sphere at the orbit of Mercury's perihelion is about 6.6e15 sq. km, so you've only built about **2 billionths of a Dyson sphere**. Yeah, space is BIG. You can see from that that you can go a long way towards a Dyson sphere before anything at all would be noticeable on Earth, and **with some level of planning, you can ensure that even a near-complete Dyson sphere does not shade Earth (or the other planets) at all.**
We got a long way to go.
---
Ok, let's talk mass requirements, at a [conservative 840 tons / sq. km](http://www.emcore.com/space-photovoltaics/space-solar-cells/), the structure required to bring us up to Kardashev I would weigh about 1E13 kg, less than the mass of Mars' Phobos, easily achievable using Asteroid belt materials (ignoring ancillary structures for energy storage, transmission, repair, etc, -- you can quadruple my estimate if you want, and then triple it again if you want to assume 30% efficiency, which still leaves you within an order of magnitude of the first estimate anyway). For a full Dyson sphere you'd need at least 5.5E21 kg of mass, which puts you around the combined mass of the asteroid belt. Throw in a few hundred massive Oort objects if you need to. So doable without dismantling planets. We might need to to some transmutation of materials, but with so much free power, shouldn't be a major issue.
---
Now, to the question of whether a genuine Type II civ would actually build a Dyson sphere, we can't really know. Perhaps a civilization so advanced has found far less crude methods to extract energy than from the wiggle of electrons on a slab facing a natural fusion reactor, from burning complex carbon molecules in a tin can, or from using atomic decay to boil water and using the vapor to make some brushes spin.
I recall reading once that there is enough zero-point energy is the volume contained by a regular mug to boil all of Earth's oceans away. And that's the stuff we know about. Who knows what wondrous tricks the descendants of Humankinds will come up with in the future?
[Answer]
That definition of a type 2 civilization is actually incorrect.
It is not being able to harness 100% of the energy of a star, but energy equal to the output of a star from any source.
This could be dyson swarms getting 10% of the output of 10 stars, or it could just be billions of fusion reactors spread over 1000 planets. The source of the energy is irrelevant, it's only the amount that matters
[Answer]
Depending on how high you want to go with your tech, there are a couple of possibilities for creating a Dyson sphere that don't involve interplanetary travel for resources.
The first is energy-to-matter conversion. Theoretically at least, we should be able to turn energy into matter. So what you'd do is start with something like a ringworld and use the energy that collects to slowly grow into a sphere. This might follow organic patterns more than mechanical - think of a genetically created Startree that collects light with giant leaves (and I mean giant on a planetary scale), and uses that energy to slowly grow itself out until it envelopes it's entire star. You could even make it so perhaps these evolved, and are spreading through the galaxy with seeds.
The other possibility is harnessing the solar wind. This is composed primarily of charged protons and electrons, and with a bit of hand-waving you should be able to start harvesting it and converting that into other materials.
Both of these will likely be quite slow - I'll try and dig up some resources and see what the conversion rates would likely be later - but they would have exponential growth, the more you grow the more you can collect, so the faster you grow. You could even combine the two and do both to grow faster. But there are a couple of other advantages. First, you don't have to go anywhere else, and second, you don't have to mess around with destroying your current solar system to build it.
[Answer]
I don't think a Type II civilization would build a Dyson Sphere because I don't think Dyson Spheres are very practical. Larry Niven explained some of the physics/engineering advantages of a ring over a sphere in *Ringworld*, so it seems more likely that a Type II would build one of those instead (and Niven had to invoke implausible materials science just to hold the ring together). Of course, if you don't want to actually live on the Dyson sphere, you can have much looser constraints, but you still have the stability problem (active management of the sphere's distance from the star).
The main trick with a ring is that you want to spin it for stability (which helps maintain the shape, but doesn't do anything for the orbit/position relative to the star). A ring perpendicular to the ecliptic would occlude the sun 2x a year, unless you also spun it with the earth (but that would introduce a bunch of forces that you probably don't want to deal with). However, if you can engineer a ring that large, you can probably come up with a way to maintain a moving hole that lets the earth-bound light through.
The real question is whether a Type II civ *needs* to build a Dyson Sphere/Ring. If you build one small and close to the star, for energy only, you need to beam it around to where you want to use it. While the sun is giving you a lot of "free" energy, it seems more plausible that such a civ would prefer to generate the energy more local to the point of use, and would likely be able to harness fusion energy at much smaller than stellar scales. Even a "micro-star" near home planet orbit would probably be more convenient than aiming a giant stellar-energy maser at/near Home.
However, a Dyson Sphere may be constructed not for civilian use, but for military defense. The civ may deem it necessary to focus their entire star's energy to power a "stellar X/gamma-ray cannon" to deter/repel enemy invasions of their solar system. Whether this involves focusing the stellar energy with arrays of mirrors/lenses, or capturing it and converting it directly via a massive laser, the point is that Type II civs must believe that other spacefaring races may one day visit them, with less than peaceful intentions. Being able to blast them out of your solar system with the full power of your star may be considered an essential first step to becoming a credible interstellar civilization.
As others have noted, such a system can very likely be built out of a medium-sized planet or less--surely with the materials we see in most extra-solar planetary systems. And if you care about Home, it should be apparent why you build this device around Home Star and not Elsewhere.
[Answer]
Peter's answer (and now Serban's as well) is mostly what I was going for (ie: get closer to the star for energy collection):
You only want a full DS (ie: cover the Sun at Earth orbit distance) if you need habitable space (and for some reason don't want to rely on artificials). If you just want the star's energy - get closer to it, which means less space / surface area need to cover the Sun. You don't need more than a couple millimeters of thickness of matter of coverage (if you're not *so* close that you've got heat dissipation problems) to collect *energy* - I mean, how thick is the solar cell in your handheld disposable calculator? Of course, you'd want something more robust/better/more efficient; but we'd probably be at least as good as *that*. You'd need *some* infrastructure to hold it in place, but not a lot, just enough to push against the solar wind. If you balanced it right, solar wind would counteract the Sun's gravitational pull.
Routing and storing all that power (90 billion H-bombs/second), of course, is a whole mess of other problems. Cabling, beaming power, whatever else - could eat up some matter.
But 'far side of the Sun' is a misnomer, and you don't want to give up the other ~1/2 of the Sun's output.
Also, you don't freeze the Earth, even if you cover a large percentage of the Sun. You leave a small belt of un-harnessed energy in the invariable plane (which is only a 6 degree belt of the Sun's surface), which will give all the planets just as much as they had been getting in the past.
That's for an unshuttered (read: less complex) system. For next to ideal, you could have something tracking each comet, and planet, and opening up a hole in your collector so everything gets the solar output it would've gotten before.
Of course, natural sunlight is vastly inefficient (but 100% natural; including all the bad things: CME, solar flares, variable output, etc). If you have that much collected/spare power, why not route it nearer each planet, and pour it out artificially, in a conditioned and nice, safe manner? Kinda the difference between a sunlamp and going outside for sun. Except you'd place your huge sunlamp far enough away that it illuminates the whole planet, and rotates around it mimicking the normal day/night cycle. Outputting everything but the neutrinos.
[Answer]
The mass of a single habitable planet is small relative to the mass of a solar system. Slightly less so if you eliminate the star.
Taking that planet apart to provide more orbiting solar collection is relatively unimportant -- in our solar system, the mass of the Earth would be a rounding error.
If we did have a incomplete Dyson sphere (from disassembling the other planets), the amount of time we'd be blocked from the sun, and the power needed to generate a "flashlight" that would replace the sun during that time, is pretty low. Assuming that the incomplete Dyson sphere blocks the sunlight no more than it would if it was randomly constructed, only 0.000000001% of the energy it collects would be required to be emitted by a "solar flashlight" to replace the sunlight that it blocks from reaching the Earth. There may be inefficiencies here, but we have lots of zeros to eat up said inefficiencies.
Note that using more energy on Earth than we receive from the Sun is relatively infeasible without building geological scale radiators: keeping a high-energy civilization cool on a plant is tricky. You could deliver it more efficiently than the above "solar flashlight" plan, and the blocking of the sun's rays by the partial Dyson sphere might be well worth it.
I speak about blocking the sun's light as being a problem, as that is about the only one I can think of from having a Dyson Sphere between the Earth and the Sun. Mass wise, the entire rest of the solar system being used to construct a Dyson Sphere within Earth's orbit wouldn't cause any orbital issues: Jupiter is 0.1% of the Sun's mass, and the rest of the solar system is dross. A 0.1% increase in the sun's effective mass might be detectable, but I doubt it would be significant.
[Answer]
Couldn't find what I believe to be true, so answering despite being late to the party:
A Dyson sphere is instable, requires a lot of material which could be used elsewhere, and is easy to destroy (for a civilisation advanced enough to build one).
On the other hand, a swarm of satellites with solar panels, covering the whole sun, is stable, requires comparably few resources, cannot easily be taken out, and does everything a Dyson sphere does, except look great.
Ergo, it is very unlikely that any Dyson spheres will ever be built, as there are more practical ways to harness the energy of a star, get comparable real estate, and so on.
As to mega structures without a sun in the middle, they would probably look more like a ring world or a very large blood cell than a Dyson sphere, as, once they get big enough to consider gravitational collapse, rotation is the only way to keep such a structure from turning into a hot star or supernova.
[Answer]
>
> I am imagining something like a Dyson Sphere would require incredible resources to build, so wouldn't such a civilizaton need to have invented some kind of interstellar travel to obtain all the resources required?
>
>
>
If said civilisation were to have the technology to turn energy directly into matter then there would be no problem finding enough raw materials. this technology actually has been [demonstrated in a lab](http://www3.imperial.ac.uk/newsandeventspggrp/imperialcollege/newssummary/news_16-5-2014-15-32-44) already! Scaled up it could provide enough matter to build a Dyson sphere
[Answer]
The issue with conceptualizing what a Type II Civilization would or would not do is that they would have the benefit of thousands of years of experience. If I were to tell you what a Type II Civilization were to do it would be like explaining to someone alive during the days of the Roman Empire how to alter image brightness in photoshop or something of that sort - it just wouldn't make sense.
] |
[Question]
[
My friends and I are building a world with a 50 mile high volcano on it. The mountain is the result of some bored god deciding to play a joke on everyone. Or, some other god got angry and decided to really, for realz this time, bury an unruly city. The legends aren't especially clear on how it got there or how it stays up. It's just there.
A 50 mile high mountain is approximately 10x the height of [Mount Everest](https://en.wikipedia.org/wiki/Mount_Everest) and 4x the height of [Olympus Mons](https://en.wikipedia.org/wiki/Olympus_Mons). 5 miles is approximately the edge of human endurance, even with supplemental oxygen. Make that volcano another 12 miles high and it will meet the internationally recognized definition of [outer space.](https://en.wikipedia.org/wiki/K%C3%A1rm%C3%A1n_line) It is a shield volcano with starting with 2° slopes at the base but no steeper than 10° at the top.
While humans have been living at altitudes around 10,000 ft (3048m) for millennia, the first recorded ascent with equipment was 1492 in France. It would take another five hundred years for humanity to develop the techniques, technology and gumption to ascend the highest peak on Earth. [Hillary and Norquay](https://en.wikipedia.org/wiki/Mount_Everest#First_successful_ascent_by_Tenzing_and_Hillary) summited Everest in 1953.
It seems clear to me that no one is going to try to ascend this 50 mile volcano while the surrounding cultures are in a pre-science mindset. I also imagine various groups attempting to make ascents then turning back because they can't breath.
It took the development of rockets and airplanes on Earth to get to near vacuum atmosphere. People on this planet can walk there. Starting from a early 1920's technology level **would their development of technology for living in a vacuum be accelerated by their ability to simply walk into one?**
[Answer]
# TL;DR
* You'll see the development of both aerial vehicles and the means to survive in harsh spaces.
* Technology *will* develop faster in this world - at least, technology related to this mountain.
* All of that will in turn accelerate the drive to go to space. Going to space might be necessary to summit the mountain.
---
I'm imagining that this mountain is certainly going to draw in people who want to summit it. Right off the bat, several groups come to mind:
* **Religious groups**, who view the mountain as a holy place (especially if a god truly did build it!). [Mount Everest enjoys such a status.](https://en.wikipedia.org/wiki/Mount_Everest#Everest_and_religion) Some sects may encourage pilgrimages, both to the base and eventually to the summit. Others may view the mountain as hallowed ground, and oppose any attempts to climb it, but I suspect they will be in the minority.
* **Scientists**, who realize that this mountain should not, according to geophysics, exist. So how did it form (well, we know this)? How old is it? How high does it go? Many of these questions will draw summit attempts, and certainly expeditions to various parts.
* **Professional climbers and climbing enthusiasts**, who know that this is The Big One. Tall peaks aren't necessarily the most technically challenging to climb, but 50 miles (80 km) of mountain certainly is.
So, you've got at least three distinct groups with stakes in getting to the summit. They will probably attempt to take different approaches, at least in the early years - first trying to figure out what the best way to get to the top is, if there is a way.
Now, I was wondering before if everyone will know how high the mountain is. After all, with 1920s technology, they can't just fly up in an [X-15](https://en.wikipedia.org/wiki/North_American_X-15) or something and get a good view from above. However, I think that with ground-based surveying, this might be possible. The height of Mount Everest was known to within a good margin by the middle of the 19th century. This mountain's ten times as high, but that doesn't mean it can't be surveyed. It will stand out from the other mountains around it - if there are any. On a very, very clear day, it's possible that the top could be seen from the ground. If not, then lower limits can be placed on its height.
## Group 1: The climbers
From surveying, would-be climbers will figure out that it's at least 50,000 feet (15 km)[citation needed], maybe more, even if they can't get a good estimate. If they've gone up any significant peak - say, 25,000 feet (7500 m) or above - then they have a good idea of the limits of the human body. Nobody is going to try to summit on the first attempt, and nobody is going to try to do it with only basic technology. Those who do will die. Quickly.
So, instead, you're probably going to see a period of technological development with partial attempts to establish camps at different elevations, like the system currently used on Mount Everest and elsewhere. Mount Everest obviously was not summited on the first attempt; there were many attempts made over many decades. I say it take 50 years - at a minimum - to reach 40,000 feet (12 km). And that's nowhere near the summit.
It's possible that the climbers are going to eventually give up going by foot. Perhaps they (minus the climbing purists) will try vehicles, like cars, when they become rugged enough. But even custom-built vehicles will have problems, and there will be points where they can't cross. In 50 miles of mountain, you'll have places like the Hillary Step that almost certainly would need to be crossed on foot.
What other technology might the climbers come up with? [Supplemental oxygen](https://en.wikipedia.org/wiki/Oxygen_mask#Masks_for_high-altitude_climbers), obviously. They won't turn back until they've tried that. Other things they might create:
* **Better insulated clothing.** I can see space suits *maybe* evolving from this, because there comes a point where a person needs to be completely shielded from the environment. Space suits are a logical extension of layers of climbing gear.
* **Shelters.** A camp system will be instituted, obviously, and given the extreme conditions above 25,000 feet (7500 m), it will eventually become necessary to seal off sleeping or resting climbers entirely. Airtight tents might be a bit much at first, but as shelters become more sophisticated as the mountain infrastructure grows, it could happen.
* **Food/water storage.** There are no grocery stores high on mountains, and no real vegetation to be found.
* **Robotic equipment.** Hear me out on this one. If it's going to take five decades to get to even 40,000 feet (12 km), then technology will progress. Computers are going to become a thing - albeit *very* unwieldy. The field of robotics could see a surge as the climbers sent scouts ahead - rovers, you could say. We already [send robots into volcanoes](https://www.nasa.gov/jpl/nasa-robot-plunges-into-volcano-to-explore-fissure/), right? Accelerate robotics by a few decades and maybe you've got something.
Let's forget the climbers now. They won't make it to the top any time soon.
## Group 2: The scientists
The scientists might also start on foot. A lot of expeditions have historically been motivated by glory, but many have also been motivated by scientific discovery. There are questions to be answered, and countless geologists would love to solve the puzzle of this mountain.
Going on foot will soon be discarded by the scientists. Unlike the climbers, the problem isn't only about the journey; it's about the destination. That will eventually include the summit. But how can they get there? Traditional planes and helicopters are out. You can [land a helicopter on Mount Everest](https://en.wikipedia.org/wiki/Didier_Delsalle), but it's dangerous. Going 50 miles in the sky is impossible in such a device. Landing on the mountain is not going to happen.
What about jumping? [High-altitude ballooning](https://en.wikipedia.org/wiki/Project_Excelsior) was possible in the 1950s . . . from maybe only 20,000 feet (6 km). Even [Felix Baumgartner](https://en.wikipedia.org/wiki/Red_Bull_Stratos) hasn't jumped from 50 miles up. Plus, they'd need extreme accuracy, whether jumping from a balloon or an aircraft. If you miss this peak, you're going to die. Also, it might be a suicide mission - although people are willing to go to Mars and never come back.
So, you can't get to the summit by going up. You can't get to it by flying straight across the sky. Can you get to from . . . space? Maybe! Something like a [space elevator](https://en.wikipedia.org/wiki/Space_elevator) could be useful (depending on the latitude of the mountain). Simply put a satellite in geostationary orbit and build down to the top of the mountain. The big drawback? We're almost a century past 1920, and we haven't figured that one out. But then again, we haven't had the impetus to do it. This might be the only way to get to the summit.
Some interesting developments will come out of all of this:
* **High-altitude vehicles** will be designed and built, to get a look at the mountain higher up, if not to reach the summit. Surveyers and climbers on the ground can only go so much; to really study the mountain, you need to fly. I expect that balloons, however, will become popular; rocket-powered places won't necessarily take the lead. Balloons may be more useful for scientific study.
* **Robots** - again. Once again, automated vehicles are often better than humans. We sent computers to space before we went ourselves. Admittedly, flying around a mountain is harder for a computer than just staying in orbit. But still.
* **Propulsion** might go in exotic directions. I've already tried to justify accelerated balloon development, but you're going to see rockets being developed, too, because people will always want to get to the top. Things like the X-15 will be developed ahead of their time - and again, this will take place over *decades*. The great thing about the development of high-altitude vehicles is that they're a natural step towards spaceplanes and other vehicles used to get to low orbits.
* **Space travel** might actually become a thing, if people decide to go all the way up to try to come down. Again, this will take a while, but people will have a *reason* to do it. And that's going to accelerate technological process.
## Group 3: The religious
These people are pretty much a wild card, insofar as they could oppose or help attempts to climb or explore the mountain. I honestly don't know what they'll do. We have nothing like this mountain - in terms of spiritual significance - in our global society, and yet this mountain will have global effects. So we don't have a whole lot of data for what this does to people, socially.
I don't think that religious groups will develop technology so much as encourage its development, and perhaps procure funding. In return, climbers and scientists may dedicate part of their missions to the religious group. Will that lead to clashes of various kinds? Yes. But it will also fuel the attempts to conquer the peak.
## At the end of the day . . .
. . . you've got developments in a variety of fields:
* Aerial vehicles, including balloons, high-altitude airplanes, and rocket-powered planes.
* Protective structures and shelters.
* Clothing designed to withstand terrible conditions.
* Advances in computers and robotics.
* Possible attempts to go to space itself, to access the mountain.
Is this useful to space exploration? Of course. You've got most of the elements you need. Is it useful to do the kind of space exploration they'll begin with (i.e. orbital exploration and satellite development)? Yes. Will it take away from efforts to go to space? No, because you might have to get to space to get to this mountain. At any rate, they'll follow the progress of early space programs - building high-altitude vehicles - while also making developments on the mountain to help live in space.
You might wonder why I'm so optimistic. Well, this target is like going to the Moon. And we did that! But the difference here is that this mountain is more tangible. It's *there*. You can walk to its base and look up. The Moon's far away, and maybe not something people can relate to as much. But this mountain? That's right here on Earth. And that's quite an encouraging target. People will develop technology to reach it, accelerating technological development in many areas.
[Answer]
A mountain that large is likely to be a shield volcano of gentle slope, so much of the climb will be relatively easy in term of climbing difficulty, and you could likely plot an ascent which would not require complicated climbing techniques. So technological all you would need is pressure suits and pressure vessels along with the ability to isolate and control gas mixtures. Most of this technology was highly developed in the late 1800s.
A good parallel to explore is the history of diving and diving technology.
<https://en.wikipedia.org/wiki/History_of_underwater_diving>
Similar to your mountain, the undersea area is just right there waiting for people to get the technology required to explore it. Diving techniques and technologies began developing in the late 1700s and was well developed by the late 1800s early 1900s. I would expect a similar timeline for the first gas mixture assisted mountain expeditions on your world.
On our planet it wasn't until the 1930s and 1940s when aircraft pilots consistently began going high enough to have problems that we started learning the details of the survival limits and mitigating technologies for survival at extreme altitudes. So your world could easily be 30-50 years more advanced in this area of knowledge and technology.
A lot, however, depends on how many people can go to the mountain and why they want to climb it. More people or a more pressing need could drive technological development much faster than if it is only a few isolated explorers doing it for personal or national glory.
[Answer]
Such mountain would likely look similar to [Olympus Mons](https://en.wikipedia.org/wiki/Olympus_Mons), with extremely shallow slopes. This in turn means that the mountain covers a huge area (see picture below, and consider that your mountain would is far larger).
Life will exist on the lower parts, gradually disappearing towards the middle. And naturally, at some point people will try to get there.
Yet, I doubt it will impact the technological progress in any way, this mission is extremely complicated. The explorers will have to cover a considerable distance, and fight through severe weather - so they need automated vehicle, durable equipment, communication with the ground etc.
All this technology comes from different fields, and generally wasn’t developed until the mid 20 century. The mountain climb challenge alone isn’t enough to spark technological progress by itself (in multiple fields) due to the fact that mountaineering is a hobby, and there’s little actual value in it.
In reality humans climbed Mount Everest when technology allowed them, and not the other way around. Unless there’s something special about this mountain (some rare natural resource near the top), it won’t be different.
[Answer]
Edit my answer to the top of this. My answer is no, the summit of this fictional volcano is harder to reach than the moon is and would have no more impact on human technological development than our will to reach for the moon already has.
>
> Starting from a early 1920's technology level would their development of technology for living in a vacuum be accelerated by their ability to simply walk into one?
>
>
>
You're missing alot if you feel a vacuum is the only thing this 1920's culture needs to contend with. Maybe I'm missing the point of the question, but...
You're actually in the Mesosphere at this point, which is sadly our least understood section of the atmosphere because it's really hard to measure (only have the time that it's being flown through to measure it). You are above most of the atmosphere here...
Point #1 - Solar radiation. Though still protected by the magnetosphere, you are well above the majority of the atmosphere responsible for filtering much of the nasty rays that aren't so good for humans. Ultraviolet and other radiation protection would be required, lest we fry.
Point # 2 - The Mesosphere is the coldest region of the atmosphere. It actually gets wildly hotter a few dozen miles above this, but the summit of your volcano is around −143 °C (−225 °F; 130 K). Being in a vacuum is one thing, being in these temperatures is another...doubtful a 1920's culture can produce something to withstand that, and important to note we are still not a vacuum at this point.
Point # 3 - Wind! Although we are not 100% sure as this is somewhat projected, but the generally accepted wind speeds (pending season) will reach around 150mph (60-70 m/s) or category 4 to 5 hurricane win speeds. What doesn't asphyxiate or succumb to cold will likely be blown off the volcano.
Sadly, they would have to cross all three of those barriers before they "their ability to simply walk into one (a vacuum)"
As a point #4 - Meteors. About 95-98% of meteors captured by Earth are ultimately burnt up while travelling through the Mesosphere, but they wouldn't burn prior to striking your volcano. The last 10 miles of ascension will also run the risk of orbital bombardment from space dust travelling thousands of miles an hour to larger rocks the would leave craters on the volcano (the space dust would likely 'sand' the volcano, giving it a relatively smooth and shiny surface on one side).
\*\*side comment - there is no liquid water up here and nothing to really 'reshape' your volcano...you'd need processes (a god?) to keep this volcano up there, or meteor impact alone would likely knock it back down. Larger impacts will remain and the top of this volcano would be utterly pock marked with impacts
So to the question:
>
> Starting from a early 1920's technology level would their development of technology for living in a vacuum be accelerated by their ability to simply walk into one?
>
>
>
A big no on your premise...simply walking into a vacuum isn't possible what so ever.
[Answer]
**Yes sort of but due to the mountain and low pressure not due to vacuum**
A 264,000 feet high shield volcano would cover an enormous area and from a military perspective (at least) there would be great interest in being able to access such an area. Any vehicle that could carry troops up the mountain would be able to out flank an enemy. Any artillery placed up the mountain would have a range and height advantage and any observation posts would also be at an advantage at least on a clear day.
So there would have been important military advantages to be had and with a mountain the size of Europe on everyone back door everyone’s military would have been very interested in getting up the mountain, preventing others from getting up there and fighting them there if they did.
Before around 1800 there might have been special young fit athletic battalions who could out climb the rest of the army who would have been valuable as climbers. But it would have been possible to block them with barriers built at the limit of endurance slowly and in shifts.
During the nineteenth century and especially towards its close things would have changed. 1884 saw the first mass produced electric cars following the first mass produced efficient lead acid batteries in 1881. This would have enabled boiler like pressure vessels containing men to have been driven up above the area reachable by men in the open.
In 1883 measurable quantities of liquid oxygen had been produced and the invention of the dewar flask in 1892 provided another spur to the military. It is now possible to send electric vehicles much further up the mountain with electric power and on board supplies of oxygen or air.
At this point you have an almost steam punk like environment for combat!
When balloon technology was sufficiently advanced some people would undoubtedly try to reach higher up, but that approach would be limited. Exploration would have expanded greatly in the 20th century.
[Answer]
Tracked cable-layer. Ascend in stages, similar to the way conventional Earth mountains are climbed. With plenty of electrical power from the cable, heavy shielding, insulation, air-compression/conditioning are not so much of a problem.
Not sure how the cable sections would be spliced, whether or not some EVA would be needed. Probably, some clever connectors and/or splicing gear could do the job without anyone going outside.
Then, onwards and upwards!
] |
[Question]
[
I saw this a while ago, and it has bothered me ever since.
Imagine a world where you know everyone is going to go crazy in exactly one day. The entire world's population will try to find and kill you, for a 24 hour period. This includes the army, policemen, friends, family (who know you, and where you could hide)...
* You have one day to prepare for this 24 hour madness
* No one will help you, you can't buy / blackmail anyone.
* They will try to get to you regardless of the expenses.
* Everyone will recognise you as the target on 'killing day'.
After this day, everything will be back to normal.
Let's assume that you are a healthy, young middle-class person living in a first world country. Any skills required would therefore need to be skills you can easily learn. A normal middle-class person isn't going to learn how to fly a plane or hack the CIA in a few hours for example.
How best could a person prepare to maximise their survivability?
What would be feasible and likely methods of survival given an average middle-class persons limited skill set and budget?
[Answer]
This is a question about breaking patterns and laying low. Disappearing isn't that difficult to do. And staying gone for just a short period of time wouldn't be that hard.
First 30 minutes, pack a quick day pack included will be a small amount of food, a pair of pliers and a firearm (this is for defensive purposes, if you don't have one don't worry about it because it wouldn't do you any good anyway). This pack needs to be as light as possible - no more than 20 lbs. - because you will be carrying it for a while. If it's a work day, call in sick to avoid suspicion.
Second 30 minutes will be driving to the ATM and pulling the maximum single day withdrawl amount which should be more than sufficient for your purposes - get away and get back. If you don't have $300, get the most you can - this will be mostly for fuel.
Third 30 minutes - getting a minimum amount of fuel and last minute "essentials" - first aid, beef jerkey, batteries, water, etc.
Next 60 minutes - driving to the airport and parking the car in long term parking. Leave your wallet, keys, phone, etc in the car.
Next 30 minutes - find a car that has recently parked and steal it. The hope is it won't be missed in the next 24 hours. Look for something older model, fuel efficient, non descript, with as little technology as possible.
You are now 3 hours into your prep time. You now have 17 hours to drive to the safest, most remote area, you can survive for the following 28 hours. This area will not have the usual indicators of survival - water, shelter, etc. It will not be anywhere near a tourist attraction, hiking trail, rest stop, etc. A national park might be acceptable but it has to be massive and accessible from a fire trail or back road.
Once there you will be hiking in for the remaining four hours, at least. Before you leave, disconnect the battery on the car with the pliers. On your hike you will be moving into the thickest, gnarliest area you can leaving as little trail evidence as possible - not cutting vegetation, breaking branches, etc. .After you've been moving for 4 hours, look for some natural shelter - ledge under a cliff wall, grove of trees, cave, etc. Hole up and pray you've done enough. You aren't surviving for an indefinite amount of time, so other than some concealment, limit your activities to sleep and listening
The idea with all of this is to break normal patterns - doing things you don't normally do, going somewhere no one will think to look for you, and commuting in a vehicle no one will think to look for. Admittedly, stealing the car is the riskiest part of the plan, but a necessary risk.
If you've picked a good spot, you'll be going home soon, dropping off a car that doesn't belong to you, will nothing but a little explaining to do, possibly, if you are married.
[Answer]
**It depends on how crazy everyone gets - but the odds are not good.**
Let's say someone is in command of a nuclear arsenal in a ballistic missile submarine. If they are sufficiently crazy, and have no other concern, they would simply launch all available nuclear missiles at random targets in the hope of destroying you.
In fact, if everyone was absolutely crazed, then all nuclear weapons in the world will be launched at all major cities (and surrounding areas) to maximise the chance of destroying you.
If this is the case, you have no hope, as there are sufficient nuclear weapons to destroy all cities. You may have at most maximum of 20 minutes to vacate a city, however this may not get you sufficiently away from a MIRV, or deep enough underground to get protection.
Even if you managed to survive the complete salvo of nuclear warheads, the environment remaining will be so hostile your death would likely be assured.
Combined with all the bio-weapon and chemical weapon arsenals also in command of crazed people, a complete wipe-out of all possible ways to survive is possible.
[](https://i.stack.imgur.com/GsahL.jpg)
The scary thing is though that people don't need to be 'crazed' for the above to happen... but simply 'rational', with a complete lack of empathy.
[Answer]
I think the best chance of survival lies on going where nobody will be.
Approach #1: Pack a day's worth of food, water and sealable waste disposal bags. The food must be low-scent and suitable for eating as is.
Take public transit to a large cave system. (Carlsbad Caverns comes to mind but I'm sure there are others that would work. I'm not sure about getting from town to the cave, though.) Enter normally, but when nobody's looking get off the path and go as deep into the undeveloped area as you can. Wait out the day, use **no** light so there's no indication there's anyone down there.
Approach #2, substantial skills required: Hire a skydiving plane to fly high over a large expanse of forest. Attach a rope to the plane and ride underneath for a period of time. At some point in the flight you let go and pull your chute--one picked to have a good glide ratio. You want to get far away from the flight path of the plane before you land. Find some sort of clearing to land in, hike a substantial distance from your landing point and hide under the largest mass of vegetation you can find. Cover as much area above you but below the vegetation with mylar blankets to break up your heat signature. Wait it out, no heat sources. You might have to call S&R afterwards if you can't hike out from where you landed.
(Hiding your drop point from the pilot is because it's a notable event, when everyone's searching for you he's going to realize his skydiver from yesterday is the target. You need to be the needle in the haystack by then.)
Approach #3, substantial skills required: Get a boat, go some miles offshore in an area with rough seas, dive. Leave the boat under power but with some spring-loaded bands rigged to pull the wheel a bit and connect slow-burning fuses to those bands--the objective is to make the boat change course a few times. Anyone boarding the boat will be able to figure out what was done but without knowing how long the fuses were (make sure all the ash ends up in one place so nobody can reconstruct their lengths) they have no way of figuring out the path the boat took to get there.
Meanwhile, you're on the ocean floor with a bunch of scuba tanks. Hide in some kelp, wait it out. When time's up you have a dive torpedo to haul you back to shore. (Note: You need a lot more air than you can actually carry. You are going to have to stop and lower the tanks into the water in several loads. So long as they are at neutral buoyancy you can pull them along once you're in the water.)
(The rough seas are to make it much harder to find your bubbles.)
Approach #4, lower chance of success: Hide out in the attic of an abandoned building that you reached by public transit.
[Answer]
**Fake your own death.**
The only way people are not going to try to kill you is if you are already convincingly dead. Even if they are not completely convinced, the day of hatred will be consumed while interested parties try to determine if the burned corpse (with 2 of your own filled teeth in its mouth) wearing your clothes in your burned, crashed car is actually you. Your note will explain why you decided to take your own life rather than run in fear. It will all be very plausible. DNA testing will take more than a day and people will come to their senses by then.
The fake needs to happen early on the day and it needs to be newsworthy - which I assume will be the case since everyone knows who you are and everyone is searching for you. Hopefully the people with the nuclear weapons / killer drones / assassin cats will hear these reports and understand there is now no reason to let slip the assassin cats of war.
[Answer]
A lot of the answers here focus on maximising the area you 'could' be hiding in, which neglects the sheer level of manpower and resources available to the searchers. *Everyone* will be looking for you, and they will all co-operate and co-ordinate with each other, regardless of expense. If you are traced to a national park, the entire populations of nearby cities will congregate on the park to sweep it, acre by acre. Every dog owner in the country will bring their dog, every army unit will bring their helicopters, every police force will bring their thermal imaging units. And they have the same amount of time to search for you as you did to hide, so whatever route you took from your home to your hiding place, everyone who starts killing day nearby can follow the same route, using the same or better technology and travelling faster because they don't have to cover their tracks. Any normal hiding strategy will result in you being overwhelmed by dumb manpower.
To mitigate these factors, your strategy has to **minimise the *number of people* who can be involved with the search for you**, as well as minimising the **technological advantage** of the searchers.
Factor 1 is not achieved simply by establishing a large, even huge, search area in any 'ordinary' terrain, because there are many, many people with similar transport and basic survival capabilities to you, and if you can reach that area and survive there for 24 hours, so can they to search for you. Instead you need to set up a search area which is only accessible with specialist technology which will not be available to most of humanity. Underwater with scuba kit is probably my favourite suggestion here, but you could also try in an active volcano with heat protection, or in whichever of the arctic or antarctic is currently in winter. The important thing is that these are good locations not because they are remote, but because the overwhelming mass of humanity that will come looking for you will *die* (and hence be unable to keep looking even if they are heedless of their personal safety) without appropriate technology.
You can also minimise the number of people who can be involved in the search by choosing a hiding area with physically difficult access, even to authorised persons. If you took a flight to night-time Antarctica where the only access is by [tiny plane](https://www.nationalgeographic.com/adventure/destinations/antarctica/antarctic-pilots-tell-of-rescue-flight/), the number of people who can be physically brought in to participate in the search for you would be very limited, even with full governmental co-operation.
Having selected your hiding area to be accessible only to people with certain technology, you then want to optimise it to be as difficult as possible to search *by people using that technology*. If you're hiding underwater, that means staying out of open water where military sonar operates effectively; a complex inland waterway system like the mouth of the Amazon or Nile would be preferable: the underwater visibility would be terrible, limiting the effectiveness of the world's [six million](https://cdn.ymaws.com/www.dema.org/resource/resmgr/imported/Diving%20Fast%20Facts-2013.pdf) scuba divers combing the water for you.
In short, you probably want to choose an environment which is as dangerous as possible for people, including you, to survive in, and hope that the fact that you chose it (and got there first) gives you an advantage for long enough for the 24hr clock to count down.
[Answer]
You aren't going to survive, everybody in the world is determined to kill you no matter what. This means that the world leaders will come to the logical conclusion that destroying the world will ensure your annihilation and as everybody wants you dead then nobody is going to disagree with this course of action.
It's unlikely that the combined might of all the worlds nuclear weapons would destroy the planet, however if they were salted with cobalt and detonated strategically around the planet for enough coverage then the resulting radioactive dust with a 5 year half life would ensure your death eventually.
[Answer]
As stated on various answers, things may vary depending on how crazy/determined people are on finding and killing you, what ressources they are willing/able to use, and what costs they are ready to pay. Despite my low level, I upvoted @flox. Without more informations, I think his answer is the best.
A friend once gave me this technic to spend a night anywhere without being noticed. Though not a full answer (which others already gave quite succesfully I think), I think it may answer "How do I spend the night in safety" :
* Put a hammock and a space blanket in your bagpack.
* Hide in a place with trees.
* Find a pair of trees you can climb. No need to go too high, just high enough to be in the "leafy parts".
* Hang your hammock there, wrap yourself in the space blanket. Sleep.
[Answer]
I find the problem with many of these answers is that they tell you to hide in the best hiding spot, or most remote area available. While this is a logical course of action, logic actually works against you in this case.
Imagine there is a national forest just an hour from your home. Logic would tell you its a good place to hide, since its got no cameras, and a lot of ground. But that also means since it is the most logical place to hide, its also logical to search for you there. As soon as the 24 hours start they will begin to blanket search the forest, in a large portion of cases leading to you being caught.
But that's less important then a lot of other factors. We really need to ask how does killing day work? Does everyone share a hive mind that lets everyone know everything your friends know about you? Does the information spread through word of mouth? Does everyone know your name or just what you look like? Does everyone drop everything and single mindedly hunt for you, or will some of them stop for lunch or take breaks. Does the rest of the world know that someone is preparing for killing day or are you the only one aware that it will happen? Do people want to kill you or do they just know you need to die and will always cooperate with everyone else? Do people still have morals or is carpet bombing/burning forests etc a viable option to catch you? What time does killing day start? Does the entire world wake up when it starts or will everyone who is asleep stay asleep until they would have otherwise woke up?
Anyways, I have two favorite solutions. Option one is to simply hide in your neighbors house. Either way till the exact moment killing day begins and sneak into their house as they leave, or break in while they're out and hide inside. A house extremely close to your own is a bad hiding place, which makes people unlikely to search it. Especially if you park your car somewhere far away from your house and make people think you're hiding in the woods or something.
A second option is a diversionary tactic. Drive to the west, buy a hotel room a few towns over. Now your name is on a hotel registry and will be quickly discovered by people searching for you. Leave your car in the parking lot. Take a taxi back to the east, keep your face obscured. Pay cash. Find a for sale house and sneak into it. Just wait out the 24 hours as everyone drives right past you to search the town with your hotel room and your car.
[Answer]
For the first 24 hours nobody will look for you nor try to find you. Once you left cities, there will be no cameras or anything that can track you.
So just pack a lunch, a bit of water, hike a few hours in the wilderness leaving the path, hide in a hole, a grove, under a bush. Try to sleep 24 hours.
I don't think anything else is needed.
[Answer]
I would think that simply leaving your immediate area for a remote location could work well enough.
After filling your day pack with enough food and water for 36 hours\*, just get in your car and head out for a random location that you wouldn't normally pick.
If you live in a city, head to a rural area, like a cabin in the woods. If you are normally rural, disguise yourself and head into town for a really nice hotel. If you like the cold, head to the desert. If you love heat, head to the mountains. Instead of doing a 180 on your normal decisions, do a 90 so it's even less obvious where you're deviating. "Jim loves his cabin in the woods, so he's definitely not going there. Probably going to hit a penthouse instead, if he's changing all of his decisions to be completely backwards." Well, guess what, Jim went to a small town instead and is hiding in an abandoned barn. It's sort of like the cabin in the woods, but it isn't the penthouse, either. Just because the hayloft isn't ground floor, it doesn't mean it's the penthouse. ;-)
Regardless where you end up, you need to stash/ditch your vehicle miles away from where you're hiding out. You may also want to backtrack, so it's less obvious where your trail is going. Don't get to the edge of town then get out and walk in the same direction, is what I'm talking about. If you're headed to a cabin, drive past your turn off for a while, then turn down a different "nowhere" road (the one's Siri doesn't know about) to stash your car before you head to your cabin. If you're going to a hotel, drive to the far edge of town, then double back to your hotel, while paying cash and giving a false name. Also, don't use room service.
You might also want to get some ill fitting shoes, so you're harder to track. You may want to add a bunch of unnecessary weight to your pack to hide better, as well as changing the length of your stride. "Sue wears a size 8 sneaker. These are size 10's extra wide. Also, this person is 60lbs heavier, has a 6" longer stride than someone her size should have, and has a limp. This is definitely not Sue." Only someone who really knows tracking would be able to spot the problems with a larger shoe and longer stride would create.
There's lots of ways to disguise yourself, which can be found online. Changing your gender of clothing is a basic one, as well as changing your attitude or how you project yourself.
A big burly guy can do this and get away with it at the right spot. I mean, if you're over 6 ft tall, somewhat heavy but still muscular, have lots of body hair with a low slung, flashy dress and act obnoxiously drunk, people will probably actively look away, especially in a small town.
A diminutive woman can change into a "business only" guy with a sports coat, briefcase, Ray Bans, and a fedora, as long as they stand up straight, walk like they have somewhere to go (without rushing), and keep their hands from fidgeting. This is a perfect "big city" disguise.
Going full "drag queen", with cosmetics applied with a trowel and a paintbrush, will change your face more than enough to make it unrecognizable to most people. This would work for men and women. You may even want to purposely apply the foundation badly, so it looks like you have a real skin problem you're trying to hide, if people look too closely.
You can also find an abandoned high rise or large factory/warehouse, then pretend you're a vagrant. Some makeup (facial appliance), dirt, ripped clothes, a dirty threadbare blanket you wear as a shawl, a nasty attitude, and never staying in one spot for longer than 30 min would keep you hidden for at least a day. Abandoned buildings tend to have a lot of hiding spots anyway, so this would be a great way to lay low. Also, not many people go out looking for homeless people, which is unfortunate and going into a diatribe about that is out of scope for this question.
If you're more of an outdoor type person and can stay still for countless hours, a [ghillie suit](https://en.wikipedia.org/wiki/Ghillie_suit) might be all you need to hide out in a grassy field.
\* I suggest 36 hours so that you have enough time to get where you're "going", hiding for the required amount of time, then getting back to your daily life. This also allows room for not allocating enough food and water for yourself during the first 2 days. The third day you can hit a store on the way "back", so it's not as critical.
[Answer]
I thought about this for a while and my conclusion is that there isn't any way to be reasonably sure to survive. Even excluding nuclear bombs or actions that could kill too many people.
You can't use a plane to go in some remote location, you will be tracked and they will exactly know where to look for you.
You can't just take the longest flight and camouflage hoping the other travelers and crew will not notice you. They will know you are there and will make the plane land as soon as possible and inspect all the travelers. Also, even if it didn't happen, the longest flight is still less than 24 hours.
So, no planes.
Now, if you just get out of your home and try to go out of town in some forest the cameras will track you from the instant you leave your home (assuming you don't have some smart camera at home, in that case they will most likely have access to the footage of whatever you did while you were at home as well).
This means they will easily follow your path and, again, find your position. Once they know you are in the forest it will take no time for millions of people to look everywhere in the forest.
I have an idea I'll leave here but I'm not too convinced:
The only thing I can think about is to spend the 24 hours trying to confuse the cameras entering and exiting from various crowded places (and possibly areas with no cameras and people) and trying to camouflage you differently every time (buy several sets of clothes so that the shopping assistants can't pin point what you wear). Then go in a construction site, find some bricks and cement, go in a corner of the building and build a quick wall around you. Leaving some bricks loose to free yourself later.
People will be to busy looking for you to go to work (in the building construction site).
You should bring with you just a few snacks and a bottle of water, something you can easily hide under your clothes. Otherwise it will be easier for people to notice you.
[Answer]
I think the safest you could be would be to make people think you are dead.
You know the people are crazy and out to kill you, and everyone is. So what you do is you get a boat (assuming you live somewhere near the water), make sure everyone knows you bought (or stole) the boat, and take things like your phone and internet access items with you. Before you go on the water you go to an anonymous sex-shop in disguise and buy yourself a blowup doll or something. Now you sit pretty at the edge of the sea with relative closeness to a military aviation base while you dress up the doll in your clothing, put some beers and fishing lines or something next to it so people aren't too suspisious. Bring lifejackets and preferably some diving gear if you have it. Paint them in darker colors so it's not as easy to pick up.
Once everyone goes crazy they'll try to kill you ASAP. The first people to reach you will be military aircraft, possibly helicopters as those are probably not going to overshoot you and are likely the first one's to get a good shot off. After they tell everyone that you were on board and destroyed your boat with little trace left you are already pretty much in the clear. Ofcourse you've already left the boat a few hours early and swam a large distance, and are now floating pretty on the surface of the sea. Judging by how difficult it is to find dead people in the water, someone who will actively dive and use (an excess of) oxygen tanks to survive would be nigh impossible to kill, assuming people will even keep looking if they've got the signal "yo guys, we just bombed him and saw him go up in flames". But since these people are crazy, you might be swamped by every single boat and helicopter within hundreds of kilometers coming to look for you, all the more reason to make sure you are under water most of the time.
The sea seems to be the most ideal solution. Even if you try to hide in the most secluded area in the world, having to go up against a searchparty that consists out of literally everyone in the world I don't think you would stand a chance on land. Any flight skills and the ability to get a light aircraft would be wonderful, as you could perhaps fly a long distance and jump out at some point, hopefully letting the aircraft fly for a long distance before it crashes in the sea. Try to land near a secluded island chain, and use a snorkel or diving gear for a day to avoid people. There's a lot less boats and people that will be able to reach random island chains, and any suggestion of your whereabouts will cause bombing campaigns and military parachutists to come looking for you quickly. Doing something like this on land and they say "well he's probably somewhere in that secluded area" will just mean you'll be firebombed to all hell. Let people search and bomb the island while you are hiding a few hundred meters away from the surf with only a snorkel sticking out.
[Answer]
Most of the current answers involve getting far away from other people. It's also possible to have a good chance of survival by staying among people - preferably large groups of strangers expecting to see unusual behavior by those around them.
If we assume that the 24 hour period begins at 12:00:00 AM, go to Las Vegas, New Orleans, New York, or some other city with 24 hour a day activity.
Bring a backpack containing multiple shirt, hat, and hoodie changes, in contrasting colors.
Shortly before the start of the period, enter a public restroom in a busy venue. Change out of your current shirt, hat, and hoodie into a different-colored one. Exit the restroom in the midst of a stream of people if possible.
Stay on foot and among crowds for the next 24 hours. Wander casinos. Go in and out of Bourbon St. bars. Wander Central Park and NYC bars and nightclubs. Keep your face obscured by a hat, hoodie, and sunglasses when appropriate for the entire day. Periodically enter restrooms and change your ensemble to a different color or color combination.
Most people in large crowds are bad at recognizing strangers, if the person's appearance is even lightly obscured. In Vegas or New Orleans most people around you will have had a drink or two, which reduces their ability to recognize you even further. Tracking by camera or by air are real concerns, but in extremely crowded venues air surveillance can be neutralized by the clothing-change countermeasure. Camera tracking is degraded by the same countermeasures, especially since even with facial recognition technology you still need a human operator in the loop to eliminate false positives; that human operator then has to follow you from camera installation to camera installation, and your periodic clothing changes will make that difficult.
Unless the scenario gives the average person a much greater ability to recognize a stranger than is currently typical, hiding in plain sight like this has at least a chance to succeed. The problem with the "Get out of Dodge" answers is that one person, in an isolated spot, is very easy track once their trail is picked up.
[Answer]
**Hide in plain sight**
Many answers here discuss pissible locations where you might arrive, and then stay there, because you can't be seen in those locations and, hopefully, you've selected a location where you are not easily predicted to be.
I'd take a different approach, based on the indication in the original question that even though everyone would be looking for you, not everyone will know exactly what they will be looking for (I'm basing this assumption off of this line "army, policemen, friends, family (who know you...)). I'll assume that a handwave provides the entire human population with the ability to identify you as the target on visual inspection, but that it would have to be relatively up close and personal, not just a passing glance.
I's suggest avoiding any fixed place, at all, while at the same time avoiding staying in any area where there is a relatively high number of people that might recognize you more easily.
Day before, step 1:
Bank/ATM, get as much cash as you can
Step 2:
Buy as many fuel tanks as you can fit in your vehicle
Step 3:
Spend every remaining fund you have filling those tanks and your vehicles fuel tank
Step 4:
If funds are available after filling up on fuel then, and only then, do you worry about water/food
Step 5:
Hit the road. Pick a direction you've never gone before, and start driving. Stick to highways where you can cover a lot of distance in a short time.
Step 6:
About 12-16 hours before you become the target, change direction, again choosing a direction that will take you somewhere you've never been.
Step 7:
A 4-8 hours before you become the target, you should be 12-20 hours out of town. Find a suitably accessible vehicle, and swap it's licence plate with yours, and hit the road again, and again change direction (but do not double back). You should now be hundreds of miles from home, in a vehicle that does not plate that easily identify you.
If needed, and if you can be sure to wake up at least an hour before becoming the target, take a nap on the side of the road occasionally. If there are still funds left over, refuel as much as possible in the final hour or two before becoming a target.
Day 2, target:
As soon as the target time period starts, no more naps or stops, just drive, changing direction every few hours. A few hours in to this day, and you can start working your way back toward home, but from a different direction. Other direction changes should take you gradually closer to home, but avoid any direct routes. This will be counter-intuitive, which is exactly the point. Everyone will be expecting you to be fleeing or hiding, not moving TOWARDS home. Military and police will start searching from your home area, working their way out, stopping traffic that is leaving the area. Family will start with known places you might be or go, and advise police and military to do the same, and they will start new search areas there, again stopping traffic that is leaving those areas. But you will have started the day far from any of those locations, and will be moving in the wrong direction to be stopped by their perimeters. And will be in a vehicle with plates that are not identified as yours. And it would be almost impossible for someone who is not a friend or relative to recognize you while you're in a moving vehicle. With a worldwide manhunt in progress, the likelyhood that a random report in a random town somewhere about a stolen licence plate will be noticed and connected to you, so your otherwise generic vehicle is just that, generic.
Once the day is over, you should be a significant distance from home still, just to avoid the center of attention, but close enough to get home relatively soon and have a hot meal.
] |
[Question]
[
Ruins of buildings, abandoned cities and suburbs dot the coasts of Earth's landmasses, inhabited by wild animals and the pieces of a once vibrant civilization. The oceans are relatively empty, the soil and dirt sapped of all its nutrients, the vegetation on earth fighting the strong winds clinging to the loose ground. Barren. Humanity seems all but gone, the planet destroyed by ignorance of its most feral inhabitants.
The inhabitants did not leave though; they retreated into their shelters to wait out the storm. The shock and fear that came with the last harvest prompted the citizens of the world for answers. Out of the chaos came Arthur Hawking, a architecture and food scientist from ICBC/Coke/Pepsi. He brought the idea of a self sustaining structure to the masses, the possibility of having everything a human needed in one building. Agriculture would occupy the majority of the structures space, but automated farming would allow a consistent flow of product to the population.
Yuma Arizona was chosen to host the structures, a small town in the south west corner of what was Arizona. This city experience the most sunlight in a year, ideal for the arrays of solar panels that would be used to ***supplement*** the nuclear power generators build into the structures. The buildings were originally going to be just for some united states citizens who could afford it, but mass hysteria after "the last harvest" made these structures seem like the only resort for all people in the world so the interest skyrocketed and the world flocked to Yuma, 10 billion people in 2081.
How large would one of these towers have to be to host 1 billion people? My story takes place in 2081 (just read [this book](https://rads.stackoverflow.com/amzn/click/com/0671242571)), and I am looking to accurately scale the buildings in my head and story. Ideally 10 of these would fit into Yuma, so they would scale vertically more then horizontally. They need to account for agriculture space, living space, and some general use space that would likely be equal to the living space (schools, research facilities, clothing fabricators, restaurants etc.). The plan is to wait out the storm, which likely would be about 1000 years (for a healthy topsoil and native animal population). Once everyone is in the structures, each one will be sealed from outside physical contact to allow nature to develop undisturbed by humans, and to restrict any potential crop blight to a single structure.
EDIT: These structures are too large to fit exclusively in Yuma, so for the sake of future answers I will allow the structures to exist in the entire Yuma County.
EDIT 2: Thanks for the help, along the way I was shown this [book/site](http://www.futu.re/#en/reader/1) and now feel like I have to recommend it. If this interested you check this out.
[Answer]
**Oh, [the pain...](https://www.youtube.com/watch?v=lFgXsXK_gK8)**
**Bedrock** is your first problem. You're not building an itsy-bitsy building like the [Burj Khalifa](https://en.wikipedia.org/wiki/Burj_Khalifa) or the [Tower of Pisa](https://en.wikipedia.org/wiki/Leaning_Tower_of_Pisa), your'e building *the building,* the biggest, honkingest, Oorah-est building on the planet. And you're guaranteed to crack the foundation if we don't go all the way down to bedrock, grind the bedrock flat, drill in a bazillion holes for metal rods, and lay the [thickest foundation the world has ever seen](https://www.wired.com/2015/11/it-took-18-hours-to-pour-san-franciscos-biggest-ever-concrete-foundation/) ... because you want to build up, not out (in a area that's just begging for more urban sprawl), which is probably a horrible idea, but let's roll with it.
So, let's [examine a geological map of Yuma County, AZ](http://repository.azgs.az.gov/sites/default/files/dlio/files/nid1628/yumacounty_1960_geologicmap.pdf). We'd need someone like Arkenstein XII to give us the low-down, but I'm betting the word "Granite" is good (My thanks to Ash for pointing this out), which is a good thing, because there's more of it than basalt. ~~Unfortunately, what you'll quickly discover looking at that map is that while you'll have good sun coverage for your solar panels, it's pretty much the worst possible place on the planet for a foundation the size of what you're looking for.~~ The situation isn't as bad as I feared, but it's still inconvenient. But, there's spots out there we can make this work because we're about to calculate our footprint size.
*If I remember my geology classes in high school correctly, the areas of the world that would be best for a honking huge foundation are pretty much the worst for solar panels. I could be wrong, though. High school was sometime during the Cretaceous Period. But it's worth thinking about.*
**Water** is your second problem. You want to be self-sufficient for a billion people. This is actually a really ugly calculation. People need to drink, dispose of waste, experience hygiene (in a sealed system w/1B people... oh, yeah), then there's crops, industry, humidity control, yada-yada-yada. I'm going to take a complete pull-it-out-of-the-air guess and suggest calculated per-person you need something like 100 gallons of water per day. Let's pretend we have 100% efficient recycling and that the recycling is capable of processing every drop of water each day (an oversimplification that literally will make angels weep). That's 100 billion gallons of water or a storage tank 13.4 *billion* cubic feet in size. If it's just half the height of the aforementioned Burj Khalifa (1,358 feet) it covers a little over a third of a square mile. Let's call it a third for convenience and just build a little higher.
So, a third of a square mile, doesn't sound too bad, and we should be able to find a nice, big chunk of basalt even near Yuma we can work with. Let's pour that sucker a solid 30 feet deep, fully reinforced and tensioned, of course, and another 2,000 feet (easy) of honeycombed water tank so we can build a support structure on top of it. It's the honeycombs needed to support the rest of the building that causes the height (which is a round guess) because they consume volume not previously accounted for.
*And it's worth noting that if you didn't have a crisis driving this process before, the diversion of water to fill that tank will cause it. OK, maybe not really, but [the resulting fight between California and Arizona over water rights](https://en.wikipedia.org/wiki/Arizona_v._California) would likely start a second civil war in the U.S.*
**Food** is your next problem. [This fascinating article](http://www.farmlandlp.com/2012/01/one-acre-feeds-a-person/) boils the issue down to a simple number: one acre per person if you do it the "natural" way (growing crops, grazing cows, etc.). That's (\*cough\*) *one billion acres under your roof.* To give you a sense of size, The United States is 2.3 billion acres. [To make things interesting](https://www.westernwatersheds.org/watmess/watmess_2002/2002html_summer/article6.htm),
just over 1 billion of those acres are devoted to crops and grazing. Considering the potential for U.S. food production, that casts a shadow on that previous article's conclusion that 1-acre-per-person was needed, but we'll roll with it. So, you need to build a building (now it has to be vertical) that houses the entire food-production land usage of the United States. That third-of-a-square-mile is looking a bit small, as is my 100-gallon-per-person estimate.
*And something must be wrong with my sources at this point. But not too wrong. People have been complaining about too-many-people vs. too-little-arable-land for a long time now. This might simply be drawing a huge underline below the problem. In other words, unless you can compress food production **something awful,** your premise isn't believable as you need a planet to feed a planet worth of people.*
Let's assume that you've improved food production technologically such that, somehow, you need only 1/1,000th the space to feed a person. Thus, one billion becomes one million ... acres (sigh). A third of a square mile is about 211 acres, so you need 4,740 floors for food production at about ten feet per floor (which is *incredibly unrealistic*) so now your building is working on 50,000 feet of altitude (which is well above the 35,000 foot average cruising altitude of a Boeing 737) and we haven't even begun to address industry and infrastructure — much less housing.
*I did say building up, not out, was a horrible idea....*
**And it's time to stop**
Yes, you can lower the height of the building by spreading out the foundation, but that causes problems with a believable foundation (remember that geological map of Yuma County). Obviously we can't conceive of a believable way to do this today. So I'm going to go out on a limb and suggest...
Your building's foundation is the size of Connecticut and the building is approximately 20,000 feet (6,100 meters) tall.
*And we won't talk about what the weather around this sucker would be like.*
[Answer]
**Putting a billion people in Yuma, AZ, including food production, industry, and commerce, would require building the entire area to a height of about 2km.**
The math:
Based on the answers on [this question](https://worldbuilding.stackexchange.com/questions/9582/how-many-people-can-you-feed-per-square-kilometer-of-farmland), we should be able to feed people using about 25$m^2$ of space, per person, using reasonable near-future assumptions about aeroponic food production. Based on [this discussion](https://resources.realestate.co.jp/living/how-much-living-space-does-the-average-household-have-in-japan/) of living space in modern Japan, the minimum living space allocated per-person is about 25$m^2$ of additional space. For modern cities, about [50%](https://www.planning.org/pas/reports/report14/) of city space is residential, with the rest being industrial/commercial. (Proportionally, if we include agricultural allocation in residential areas, this will increase to about 66% of our space.) Additionally, modern cities are around 30% roads. For a megastructure, we'll also need a lot of space to allocate for atmospheric control. Let's assume that's about the same amount of space as roads.
As a per person estimate, we'd then need $50 \times 2\times1.6=160m^2$of space to account for transportation, food, housing, industry commerce, and atmospheric infrastructure. A billion people would then need a total of 160 billion square meters of space.
Using the [Burj Khalifa](https://en.wikipedia.org/wiki/Burj_Khalifa) as an estimate for floor height, each floor will be about 4 meters. Yuma AZ covers around 300 square kilometers of space. Assuming we stay roughly within its boundaries, we'll need $\frac{160\text{ billion }m^2}{300\text{ million }m^2/\text{floor}}$, for a total of around 540 floors, at a total of **2160 m tall buildings.**
This, notably, does not include the area you'll need for solar panels, if that's what you're using for power. Solar panels, notably, cannot be stacked. Sunlight provides around 1kW/square meter of energy. Assuming our crops need about the same energy input as the sun provides, and that crop production is about half of our total energy needs, we'll need 50kW/person, for a total of around 50 billion square meters, or 50,000 square kilometers of area for solar panels. That's assuming maximum efficiency: modern solar panels are something like 10%-20% efficient, so you'd need 250-500,000 square km of solar panels. (Cuba, for reference, covers around 100,000 square km.)
If everyone is to fit in Yuma County, rather than the current city limits of Yuma, the available area increases by about a factor of 50. Under that assumption, you'd cover the entire area to a height of about 50 meters to house a billion people, or 500 meters to house ten billion. 500 meters is about the height of the inhabited portion of the Burj Khalifa, though unlike that building, the megastructure would cover an area of 14000 square kilometers or so. Solar power will require the same area, which will likely be infeasible without either extensive automation to do maintenance or a substantially more dispersed population.
**Addendum:** I misread the question, and though you were only putting a billion people into Yuma. For 10 billion, these numbers would increase by a factor of 10. Using current or near-future technology, I'm not sure a 20km building is anywhere close to feasible. Also, your solar panels will cover an area close to the size of the EU, so you'll probably want to spread your towers out through an area about that size, anyways.
[Answer]
**Very. Very. Very large.**
Just for some comparison, have a look at a [project of this type](https://en.wikipedia.org/wiki/Shimizu_Mega-City_Pyramid) being proposed for Tokyo bay. Remember, you're not just building a giant apartment block. You need to account for places people work, create food, eat food, most of the stuff you'd have in a regular city.
>
> The structure would house 1,000,000 people. The structure would be 730
> meters (2395 feet) high, including five stacked trusses, each with
> similar dimensions to that of the Great Pyramid of Giza.
>
>
>
So you'd need something a THOUSAND times larger than this.
Let's try some math here... The greatest density of human occupation right now on a large scale is Manila. [1.6 million people occupying 38.5 square km.](https://en.wikipedia.org/wiki/List_of_cities_by_population_density) It tops out in District 6 with around 70k people per square km. (This is almost three times the population density of Manhattan, btw...).
Now, trying to turn SQUARE meterage into CUBIC meterage is a tricky problem, but [I've played with before.](https://worldbuilding.stackexchange.com/questions/100380/giving-tolkien-architecture-a-reality-check-dwarvish-kingdoms/147170?noredirect=1#comment460014_147170) I wound up with a rough approximation of ~2.7 cubic km for Manhattan (~1.6MM population) and ~7.75 cubic km (8.6MM population) for all of NYC.
So your starting point is **around 10MM people in a cubic building that's about 2km on a side.** Manila triples that population density without TOO much trouble, so let's say we can go up by a factor of 5. Now we're up to 50MM in a 2x2x2 cube. Now we get rid of all the roads, all of our transportation of people and goods uses conveyer belts and elevators a la a la [Caves of Steel (Asimov, 1953)](https://en.wikipedia.org/wiki/The_Caves_of_Steel). Let's say that gives us another factor of 2 in terms of space efficiency.
**That's 100MM people in a 2km cube. You need at least ten of these.**
[Answer]
I can't tell you how big the whole structure is going to need to be but I can give you a couple of figures that will help you get your head around the scale:
* Farmland, you'll need the equivalent of 25000 [Hectares](https://en.wikipedia.org/wiki/Hectare) (roughly 62500 [Acres](https://en.wikipedia.org/wiki/Acre)) of farmland to feed that kind of population, hybrid [Aeroponic](https://en.wikipedia.org/wiki/Aeroponics)/[Aquaponic](https://en.wikipedia.org/wiki/Aquaponics) systems may reduce the overall volume this requires but that's the land equivalent. Certain [fungi](https://en.wikipedia.org/wiki/Quorn) or a suggested technology that could assemble basic carbohydrates and proteins from atmospherically sourced oxygen, hydrogen and nitrogen (not sure how viable that is by the way) will get this number down but it's still going to be huge.
* Accommodation, based on tiny houses you'll need at least 50m3 per person to carry out the basics of life; eating, sleeping, and washing. You can probably half that, or better, using communal facilities and assigned shifts but quality of life will suffer badly.
That doesn't cover anything but the absolute bare essentials either, so no luxury foods, i.e. anything that grows on a tree or needs terrestrial living space (so very little fruit and nuts, no red meat, dairy, poultry, or eggs), and no physical recreation space, shared or otherwise. You also need to factor in "migration space", the corridors, elevators, stairwells etc... that people need in order to move around the space you create, and "utility space", the ducting, wiring, and piping to carry the necessaries of air, water, and power. Plus you need to generate the power and source and clean the water and air. Power for farming will need to be sufficient to supply at least 5Wm-1 of tuned red-infrared lighting for maximum photosynthetic efficiency. Human inhabited spaces will need full spectrum lighting to keep people healthy.
Technical note: a [Megastructure](https://en.wikipedia.org/wiki/Megascale_engineering) is usually at least 1000km in at least one dimension so the current footprint of Yuma is too small to put even one into.
[Answer]
Well, you're powering this by solar. So you need enough space for a billion people's worth of solar. Elon Musk calculated this for the population of the United States, which is roughly a third of what you have. From [here](https://www.freeingenergy.com/how-much-solar-would-it-take-to-power-the-u-s/), we have
>
> If you wanted to power the entire U.S. with solar panels, it would take a fairly small corner of Nevada or Texas or Utah; you only need about 100 miles by 100 miles of solar panels to power the entire United States. The batteries you need to store the energy, to make sure you have 24/7 power, is 1 mile by 1 mile. One square-mile. That’s it.
>
>
>
So figure on thirty thousand or so square miles. That's a square about 180 miles on a side. Or 300 km. You want to put the people inside though. That's going to crank up the power requirements. You need artificial light for crops and air circulation. So let's double that to 360 miles or 600 km on a side. That's how big your solar arrays are. Assuming we put those on the roof of your megastructure, it needs to be at least that big. That's 360,000 square kilometers or 130,000 square miles.
That actually should be enough. You could make the whole thing one story and it would work. You could add a second story and increase your space by quite a bit beyond the bare minimum. With proper construction, they could do that after moving into the space. The important part being to push the foundation down farther than they'll have to dig. They might also put the batteries in that basement area as well, but those will only take up a fraction of the space.
If you're powering things by solar and want isolation from the planetary environment, you might consider moving off world. You could build a space station that could get solar power constantly with no breaks for night or weather. Then you don't need batteries. It would also be easier to build a cylindrical station in pieces so as to expand it after the beginning. Or just build new stations.
If off-world, you could terraform Mars, Venus, or even the Earth. That's much more difficult if you're stuck inside one big building on Earth.
[Answer]
## Forget about volume - you need surface area
The answer by @Brythan answer goes into the right direction: identifying **solar power**, i.e. the sun-exposed surface of your building as the **limiting factor**.
However, the VAST majority of energy would be used to grow food - it's still the only sustainable way, and regardless of whether you do 'classic' agriculture or hydroponics or anything: you'll need the suns energy to somehow make your food plants grow, otherwise your population will starve.
I.e. you need enough surface to get the wattage by the sun to grow plants for 1B people. The order-of-magnitude calculation for this is 1 acre per person, so we're talking **1 Billion acres of needed surface area** (4'046'856.422 km²). Now, this might be optimised on to some degree - but **even if you get this down to 1%** with the most efficient agricultural tech imaginable your building - i.e. some 40'000 km² - you'd still need to cover more than 10% of the entire area of Germany.
It doesn't matter if you build your building 1 or 10 or 100km high - if you don't get the surface area exposed to the sun you will not be able to produce enough food.
[Answer]
This is going to sound odd but here goes anyway. According to biblical prophecy there is a city that will descend to earth that is described as being 1500 miles square by 1500 miles high with 12 gates, 3 on each ordinate direction.
There are only two possible structural shapes that this could take: cuboid or pyramidoid. The trouble with cuboid shape at that scale is that it does not meet the "square" requirement due to curvature of the earth meaning that the only possible shape for an hyperstructure would be triangular in section such as conical or a polygonal based pyramid. The Kingdom from Heaven shape would be like the Giza pyramid.
This structural fact means that the ancients knew of the forces related to building on unstable soil /rock structure yet mimics a prophecy yet to come true.
By my calculation, that City from God would house up to 4 trillion people in their own square mile quarters of self sustaining agronomy with a river welling up from the centre of the base flowing eastwards out the city gate.
To get an idea of the scale, look at a map and describe a square perimeter from Morocco to the Shetland islands going east to the Black Sea then south to Ethiopia and back west to Morocco. 1500 Square miles. The Eastern central gate is where Jerusalem is today. Imagine for a second that walks of a city must ascend vertically for a cuboid on a sphere and very soon you recognise that 1500 above the earth the perimeter is no longer 1500 miles square. The structure would be sectional of a larger sphere and the sheer mass that the earth's cost would have to withstand would be dwarfed against such a structure.
Were it a pyramid shape, the forces would be better distributed across the earth's surface and capable of resisting such weight because the weight would be less than a third of the cuboid weight over the same area.
In your city, such a structure would be a good idea because the vast living area would be near the peak and agricultural area on the base below water storage facilities.
With a pyramid structure there are sufficient surface areas to capture rain and generate power by several means (hydroelectric, hydrostatic pressure, thermal differential, hydrothermal, solar hydroinsolation, wind and hydrogen dioxide reactors. The solar panel idea of sustainable energy is not sustainable as the materials are sourced from great distances to their final destination.
To understand how such large cities need to work we need to understand biotropic design and sustainable energy without accessible fossil fuels.
The shape of the building determines the surface area for solar power. To his 1 trillion people requires a quadrilateral pyramid 1500 miles square and 1500 miles high. Since the scale set by op is 10 bn, it is order of magnitude smaller and therefore 1 thousandth smaller meaning 15 miles square by 15 miles high. Since atmospheric oxygen is a limiting factor, the highest it could be built is 5000ft which means the remaining volume expands horizontally and requires a different shape based upon a triangular polygon.
An hexagonal based ring with a triangular section would reach 5000ft safely but the outward sprawl would be substantially larger and consume some natural features in its construction such as mountains and valleys. Such an undertaking would deplete vast water resources in the construction so technically, impossible to build in the given circumstances described
Hopefully this enlightens you on the structural issues limited by oxygen, materials, energy and water.
] |
[Question]
[
In the lore of the world I'm building, the Dwarves used to have a very large territory surrounded by more or less impassable mountain ranges. This territory shrunk significantly when the elves got four dragons (the only dragons in existence and the only dragons to have ever been seen) and quite simply burned down enough of the mountains to force the Dwarves out of a lot of their land.
My questions are as follows:
1. Is this feasible to have happened? I know the melting point of igneous rocks is about 1200°C. Do you think four dragons could achieve that heat?
2. How long would they have to use their fire to burn down significant passages into the mountains?
3. What would the burned parts of the mountains look like now that they've been melted down and had time to cool?
**EDIT**
Since [@NeilSlater](https://worldbuilding.stackexchange.com/users/61/neil-slater) pointed out that to properly answer this question I need to better define how dragons in my world work, I present you with the following:
1. I suppose I mostly want to know what it would take to make this feasible, as opposed to if it is feasible. What temperatures for how long would be needed to achieve this?
2. Keep in mind that the *entire* mountain doesn't necessarily need to be melted down, just enough to bring it from impassable to passable. This way the Elves can plan future raids on the Dwarves.
3. I'm more than fine with assuming that the mountains are tunnelled out for the purposes of this. (thanks [@DaaaahWhoosh](https://worldbuilding.stackexchange.com/users/6507/daaaahwhoosh))
[Answer]
You will require an extremely large amount of energy to do this.
The [heat capacity of granite](http://www.springer.com/cda/content/document/cda_downloaddocument/9783642340222-c2.pdf?SGWID=0-0-45-1456221-p174676272) is $0.79~\text{kJ}/\text{kg}/\text{K}$ and the [latent heat of fusion](https://books.google.co.uk/books?id=aAnxRS363lIC&pg=PT1119&lpg=PT1119&dq=latent%20heat%20of%20fusion%20of%20granite&source=bl&ots=TpeKGsexkK&sig=ZdGvr8bpWd-h_0z7wTER8mFF7s0&hl=en&sa=X&ei=seDsVNbFEsflUoDkgqAH&ved=0CD4Q6AEwBQ#v=onepage&q=latent%20heat%20of%20fusion%20of%20granite&f=false) is $400~\text{kJ}/\text{kg}$. Granite weighs approximately $3000~\text{kg}/\text{m}^3$.
To create a valley $20~\text{m}$ wide across a $3~\text{km}$ long by $1~\text{km}$ deep mountain pass for invasion, the dragons will have to output
$$
\begin{align}
&3~\text{km}\times 1~\text{km}\times 20~\text{m}\times 3000~\text{kg}/\text{m}^3\times\left(1200~\text{K}\times 0.79~\text{kJ}/\text{kg}/\text{K}+400~\text{kJ}/\text{kg}\right)\\
&\approx 2.4\times 10^{17}~\text{J}=240~\text{PJ}=58~\text{Megatons of TNT}
\end{align}
$$
alone, in order to melt all the rock in the mountain pass. This assumes the heat transfer is perfect, and no losses occur during the melting process.
This is greater than the [entire energy output of the Tsar Bomba](http://en.wikipedia.org/wiki/Orders_of_magnitude_%28energy%29) (the largest atom bomb ever detonated), at $2.1\times10^{17}~\text{J}$.
The elves will be much better served if they used the dragons as troop carriers, much like [this question](https://worldbuilding.stackexchange.com/questions/10688/how-effective-would-dragon-dragoons-be).
[Answer]
# Mountain Happens to be made of Gunpowder
I don't know where your story sits on the Sci-Fi / Fantasy spectrum, so this answer may not mesh with the feeling of your world. However, I think the most fun way to burn down a mountain would be for there to be large naturally occurring deposits of niter and coal throughout it. Both of these minerals naturally occur in large deposits in our world. They are stable on their own, but if a dragon got enough burning for a chain reaction to begin mixing the deposits, the explosion could be self sustaining until all deposits were burnt up. This mix would have approximately the energy density of gunpowder, or 3 MJ per kg, and the mountain would require about .4 MJ per kg to melt, so to melt the entire mountain, it would have to be 1/6 to 1/3 coal and niter to begin with.
[Answer]
There are quite a lot of factors that make this scenario unlikely:
1- Air gets less dense the higher up you go, meaning that any fire your dragons produce is going to lose potency at higher altitudes, like the ones you'll find on mountains.
2 - Mountains are very large, and all that mass has to go somewhere. You may be able to melt the rock, but vaporizing it is pretty much out of the question, so now you've got molten rock that has to stay molten as it rolls down an entire mountain. Basically, your dragons are going to have to put out more energy than the average volcano to pull this off, and they'll have to do it for a very long time. For peak efficiency, probably two dragons would moltenize the mountain, while the other two maintained a river of molten rock, keeping it hot enough to flow all the way to some nearby valley. This process would actually get harder the further along you went, as you lose the benefit of gravity.
So, since I've said some reasons why this would be hard to do, I think it's time I gave some potential solutions. For instance, suppose the mountain was already somewhat volcanic. Perhaps there was magma swirling around, and hot gases building up in caves, searching for a way out. The dragons would exploit this volcanic activity, using the gases to blow holes in the mountain and the heat of the magma to enhance the heat of their own fires. **EDIT-** If you give your dragons demigod status, perhaps part of their power comes from their ability to bend natural forces to their will. Thus, perhaps by their power the earth below the mountain opened up and fire came forth, and this fire they channeled through their own bodies until the even the hardiest stones of the mountain could not help but yield, et cetera.
Another possibility would be that since it's a Dwarven mountain, it's already been mostly hollowed out. The dragons, which I assume are large, could use their fire to weaken the rock, then simply knock the mountain down. At that point, they could probably melt some remaining boulders and such, but the bulk of the work will be over.
As for how it would look, I'd suggest looking up pictures of volcanic islands.
[Answer]
No, it's not feasible for them to burn down the mountains, given that mountains don't really burn, and are enormous.
Usually legends are metaphorical rather than literal.
Often stories have other truths behind them.
Perhaps the dragons used magic to somehow set off large volcanic eruptions which resulted in passable terrain. Or perhaps the dragons somehow knew where there would be a huge eruption, and told the elves they were using magic to cause it, to increase their standing with the elves. Maybe they even told them they were burning down the mountains themselves, taking credit for an eruption they already knew about, but the elves had no way to know any better, or something.
The Mount St. Helens eruption shows an example of a mountain reducing substantially in size through eruption. A variation in shape and scale could result in a similar but even more passable aftermath.
[Answer]
I think you'll need to include some ritualistic element for this to be feasible. The amount of energy required here is stupid huge as other answers pointed out and if you want the dragons to be responsible for it, you need to put those dragons to an incredibly high power level (screw fire-breathing, I spew Tsar Bomba's out my \*\*\*). If you want these dragons involved again at any point in the story, you now have to deal with the incredible power level you put them at...how could any character contend with a being that melts mountains when asked? (you do need to wonder what the elves possibly could have offered 4 beings that could melt giant segments of the globe they live on).
As an alternative...assuming you are going with magic of some degree here...a ritual that needed to be preformed by all 4 dragons that isn't easily repeatable that melts the mountain might be a bit more feasible for your plot line in that the power level of each individual dragon can be greatly reduced.Perhaps it's a summoning ritual where the 4 dragons were capable on a combined level of summoning a gigantic fire elemental the just sat in the mountain (superimposed?) bored out of it's mind and heating all area's of the mountain at a constant rate. Mountain melted, 4 dragons capable of doing it, but not a single dragon capable of launching fire with the heat potential of fusion bombs.
[Answer]
This question: "Do you think four dragons could achieve that heat?" is going to depend on how dragons work in your world. And answering that is going to answer most of the rest of your questions, one way or another.
You could simply say it happened, how long it took etc, and this sets the bar for how powerful dragons are in your setting. There are no reality checks here, unless you want to set specific measurable traits on your dragons, such as declaring the temperature and area covered by a dragon's flaming breath. Perhaps you need to do that for other purposes, in which case you could comment or update what your premises (or rules if this is for an RPG) are for dragons in general.
The story could also be set in a mythological/heroic age with respect to your current timeline. It is very common in mythologies to have more potent forces acting in the world, the further you go back in time. After all, something needs to explain how the sun and moon behave, and they are far larger than a few mountains.
[Answer]
Instead of trying to melt an entire mountain, take a look at how quarries break apart rock.
They don't drill every square inch with dynamite and pulverise everything in one go - the most common approach is to get to a position where you have a "cliff face" and then using carefully placed explosive charges, sheer off a layer from the cliff face.
Focused heat can crack rocks. If you are smart with where you focus the heat from your dragons, you could possibly get a similar effect to sheering off a layer in a quarry. And if your mountains are impassable, I assume it is because of a high amount of vertical cliff faces. If your world is similar to ours in terms of geography, those vertical cliff faces will eventually drop down to streams or rivers in each of the valleys.
Assuming this is the case, sheer off enough rock from higher up, you'll block off the valleys and create dams/lakes. To then traverse the valleys, you simply drag some light weight boats up your new "dam wall" and sail/row to where you need to get. As a bonus, the flooding of the valley floors will also force the dwarves out of those areas - not fun being in a cave when it floods!
[Answer]
(Sorry in advance for my weird english)
Well, you have many answers about the feasibility of your dragon attack, and it doesn't go very likely in your way. But here are some alternatives :
* *S##t up, it's magic !* : Your dragon don't just spit fire, they can **spit magic matter** that can melt whatever your dragons want to melt, just like acid or cotton candy in water...
* *They're dwarves !* : You don't have to melt an entire mountain. Draves are "known" (maybe not in your universe) to **dig tunnels**. Maybe you could use your dragon to **"dig/melt" a hole to these tunnels** and then make your elven army walk through them. For the story, it could make a good backstory/legend/whispers about abandonned mines and tunnels which could be located thanks to spying missions with "elite" elvens or whatever you see fit your universe ...
* *Delete the problem !* : If the mountain is still a problem, then **replace** it by a **deep black and dangerous forest / noxious infested swamps** ! Your dragon could entirely burn the forest / dry the swamps, which would still keep the "powerfulness" of the dragons, passing dangereous and unexplored lands ...
* *F##k it. Badass Dragons !* : as last possibility, and depending if you want your dragons to be **immensely powerful** or "**realistic**", then you can just make them do melt the mountain like it was nothing. Like this, your dragons look impressive and can just be feared even more. Narratively, you could drescribe the melting mountain with images like "**tides of lava**" / "**sea of fire**", as the melted and fluid matter flows down the other side of the mountain toward the dwarves' lands.
However, the situation raises anoher problem, which is that 4 "mountain melter" dragons are using their power pretty uselessly... i mean they can melt a mountain, why not just destroy dwarves' armies and villages instead ?
Anyway, if you found what you were looking for, good for you. Your story made me think and imagine stories about and around your universe, and it's always funny to do so. Thank you :)
[Answer]
Maybe we should change the way that the dragon fire is produced.
A normal household dragon is more or less a napalm bomb on legs. It produces fire by spraying some burning liquid or gas and ignites it afterwards.
BUT:
There's another way:
Stage free for the Hydroxy Dragon!
Say what?
If the dragon can produce some electrical arc in his mouth it can spit pure water through the arc. The water will be split into hydrogen and oxygen and recombine afterwards (releasing a large amount of energy that will literaly melt the stony mountain).
A more practical use is the dragon named Multiplaz 3500:
<https://www.youtube.com/watch?v=VML-uRXyxHI&list=PLFF1285C2AC469A6E>
<https://en.wikipedia.org/wiki/Oxyhydrogen#Brown.27s_Gas>
I know it's no common approach to dragons, but it'll surely melt down parts of the mountain in decent time.
(I know the arc needs a tiny bit of handwaveium, but on the other hand, eels can produce electricty too)
BR
Alex
[Answer]
You could use the dragons to meerly burn through or weaken the structure around the magma resovoir of a dormant volcano.
Mt. Saint Helens erupted after a huge landslide reduced the weight of the "lid" and maybe shook things around deep down.
Ski resorts use explosives to trigger avalanches while closed rather than waiting for it to happen.
So what would happen if a missle hit Mt. Rainier?
---
Another idea: the residents of the mountain use it for mining I presume. What if they are mining something like a magnesium deposit?
[Answer]
What if the mountain contained [**Thermite**](http://en.wikipedia.org/wiki/Thermite)? It doesn't have to be made completely of thermite, just some above critical amount in dirt and rocks in a form of veins, ... that will sustain the reaction. The rocks would crumble or explode under the heat and fly apart.
[Answer]
You want to melt down the mountains, ok, but... **Where will they flow to?**
This isn't a little bit of rock we are talking about, melting that amount of material will make rivers and/or lakes of lava that will take from weeks to years to cool off unless aided by powerful ice magic.
Maybe have the dragons melt part of the mountains, making them flow into the dwarven lands. That way they did melt the mountains, the dwarves get a horrible situation to deal with, and meanwhile the elves march from wherever they want unimpeded by dwarves that will be too occupied with putting down fires and digging trenches to route the lava away from crops and buildings.
**If you absolutely must melt a mountain...**
Make sure it's the smallest and/or most dug out of them all to mitigate the problems, unless waiting years for it all to cool off is reasonable for both parties, remember that the new pass can be used by the dwarves as well as the elves.
[Answer]
Other people have been discussing how to actually remove the mountains themselves, but there is another take on this to consider.
[Scorched earth](http://www.wikipedia.org/wiki/Scorched_earth) is a type of military tactic of destroying everything that might be of use to an enemy in an area, in order to render the area completely unusable for farming or industry, by polluting previously arable land with the soot, causing large-scale erosion problems (as there are no trees to hold the land together anymore), and burning bridges, demolishing roads, and razing cities to the ground. In your case that would mean collapsing tunnels, too.
Assuming these are near-surface dwarves (as opposed to rock-eating, lava-drinking, "what's this 'surface' you speak of?" dwarves), such measures would force the dwarves to leave. Even if they were not farmers themselves but only traded for food, there would still be no food available as nobody else could grow it either. The destruction of their tunnels and roads would make it difficult to get food to the scorched regions from elsewhere. Combined with continued military pressure, this would easily be able to exterminate or force the dwarves to abandon the area.
So while geologically there would still be a mountain, it would no longer be a dwarf mountain. The tales and stories told of this great burning wouldn't bother to distinguish between physically destroying the mountain or "merely" emptying it and destroying its former inhabitants. No need to literally destroy it.
[Answer]
If you have Granite or Quartzite as the primary rocks that form your mountain range then you don't need to melt the mountains, just heat them up a reasonable amount, 50 celsius or so, at night, especially if you can also get large quantities of water onto them as well. Granite and Quartzite are especially susceptible to thermal fracturing and break up quickly under heating/cooling cycles, if you can add water then frost wedging also takes place accelerating the weathering process even further. You should be able to cut many exfoliation layers lose every night, fewer, deeper layers if using ice and fire instead of just fire, from a large area. Each layer of heat only exfoliation is a few centimeters deep so you could break off up to a metre of material a night, possibly double that if you can water the cracks and use freezing as well. If the days are cold enough you can in fact keep this up all day as well as all night, it won't take that much forced erosion to make vertical walls into passable scree slopes.
] |
[Question]
[
Assuming that the observer is on the moon for a full lunar cycle, would the appearance of the planet wax and wane, would the moon's shadow occlude the planet during an eclipse while on the moon?
[Answer]
The planet, as seen from the moon, would undergo a cycle of visibility, going from full "planet" to new "planet" and back, depending on the mutual position with respect to the star, like in the following examples taken from the Moon:
[](https://i.stack.imgur.com/vjUSP.jpg)
[](https://i.stack.imgur.com/p5Pg2.jpg)
About casting its shadow on the planet, it can happen, too, if the shadow cone intersects the planet body.
[Answer]
[Stellarium](http://stellarium.org/en/) is an awesome open-source project if you want to answer those kind of questions.
You can specifiy the location and time you'd like to observe the sky. The location isn't always on Earth, you can also pick the Moon, Jupiter, Mars, Saturn or any of their moons!
# "New Earth"
Here's a screenshot of a "new Earth" as seen from the Moon.
[](https://i.stack.imgur.com/xCHxv.png)
# "Waxing Earth"
[](https://i.stack.imgur.com/3mu9a.png)
# "Full Earth"
[](https://i.stack.imgur.com/smDag.png)
# "Waning Earth"
[](https://i.stack.imgur.com/tD0KX.png)
# Solar Eclipse on Earth, seen from the Moon
Moon's shadow on Earth during an [eclipse](https://en.wikipedia.org/wiki/Solar_eclipse_of_August_21,_2017) should be visible with the naked eye. Earth as seen from the Moon is 4 times larger than the Moon as seen from Earth.
A small amateur telescope might be needed in order to see the path of totality.
[](https://i.stack.imgur.com/4PL7r.png)
# Lunar Eclipse on Earth, seen from the Moon
A lunar Eclipse on Earth is a solar Eclipse on the Moon. Here's one in [July 2018](https://en.wikipedia.org/wiki/July_2018_lunar_eclipse):
[](https://i.stack.imgur.com/X9GTX.png)
The Earth's atmosphere would look like a [ring of fire](https://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=4341)!
# Fun facts
* Note that the Earth doesn't move at all in the Lunar sky, due to ["tidal locking"](https://en.wikipedia.org/wiki/Tidal_locking).
* "New Earth" always happens during the lunar day (i.e. "Full Moon").
* "Full Earth" always happens during the lunar night (i.e. "New Moon").
* One lunar day is what we call a month.
* During a lunar day, Earth rotates on itself approximately 29 times (while staying at the same position in the sky), so every part of Earth will be visible multiple times.
[Answer]
I understand this has been pretty thoroughly answered as a decisive "Yes", but I wanted to offer another literal point of view.
As you can see in the image below, the sunlight always comes from the same direction for both the sun and the moon. You can see that as the moon orbits the earth (a lunar day), different lighting conditions exist along the way. They are in fact opposite of the current phases of the moon, which I think is just neato.
In the first quarter, standing exactly in the middle, you can see the opposite phase of the earth. In this case, what looks like the third quarter. As the moon orbits counter clockwise to the Waxing Gibbous, the earth's new phase is directly opposite in the graphic, meaning it is now Waning Crescent from your point of view. Follow one more phase to when it's a full moon (Lunar "noon"), you can see that the earth is now covered in shadow. A "New Earth" if you will. You can continue along the path in the chart below to see how the moon orbits and how the faces change. In the moon-sky, the light and shadow would move "right to left" the same way our moon does in our earth-sky.
Now, we also note that the earth is spinning once every 24 hours. But this has no bearing on how we see it as far as the direction of light goes. Normally we take this for granted, that the moon is tidally locked with the Earth. So as the phases of the Earth progress, you may notice that different parts of the Earth, different features like countries and oceans, are visible to you. It may even appear to "rock" back and forth as the seasons change (the phases still appear normally). But how the Earth spins has no bearing on which parts of it are lit.
[](https://i.stack.imgur.com/paVQO.jpg)
[Answer]
A "full planet" occurs when the moon is between the planet and the star. A "new planet" occurs when the planet is between the moon and the star. So as long as which one is closer to the star is changing, the planet will wax and wane. For the planet to not wax and wane, you'd have to have a really weird situation, such as that the moon's plane of rotation is perpendicular to the line between the planet and star.
Note that a *perfect* full planet would mean that the moon is exactly between the planet and the star, which would mean that the moon's shadow is being cast on the planet, so the planet would see a solar eclipse, and the moon would see a planet eclipse. In a perfect new planet, the moon would see a solar eclipse and the planet would see a lunar eclipse. Whether those would be total eclipses depends on their size and distances. What we call a "full moon" is not a perfect full moon, as the moon is usually not on exactly the same plane as the earth. When it is on the same plane, and the moon is opposite the sun, we get a lunar eclipse rather than a full moon.
[Answer]
Are you talking only about the Earth and the Moon? If you are talking about any moon around any planet, then the view would also depend on the plain of rotation of the moon around the planet.
If the moon orbitted on a plane perpendicular to the planet's orbit around it's star - imagine the star to the left, the planet in the centre and the moon (appears to be) moving up and down - then it would only see the normal "wax" and "wane" when it crosses the planets orbit, at other times (especially when position above or below) the planet would just be half/half all the time.
] |
[Question]
[
Suppose I have a machine that lets me see the near future, and I want to use this to get rich on the stock market. What is the best way to invest so that no one suspects that I'm doing something fishy?
EDIT: The point is to not just to have an excuse that people will believe, the point is to not draw any attention at all. Examples of what NOT to do include:
* Obviously, if you invest everything in the single highest yield stock, you might be suspected of insider trading.
* If you consistently pick the several highest yielding stocks, even if you aren't suspected of insider trading, people will take note that you are outperforming everyone else. (This is sort of what happened to the [Magnetar trade](https://www.propublica.org/article/the-magnetar-trade-how-one-hedge-fund-helped-keep-the-housing-bubble-going).)
In either case, you get attention for your success. How does one avert that?
[Answer]
>
> Suppose I have a machine that lets me see the near future
>
>
>
First things first : secure this and have a discrete way to use it.
How near is near ?
investment strategy is dependent on how long terms your investment is for, but how suspicious your apparent success at picking investments will look is also dependent to some extent on how much time passes between buy and sell.
It also depends on how you deal with the sell part.
Selling at the peak every time will look suspiciously like you know too much.
Sell using conservative strategy that may not optimize your profit but will look like someone making reasonable profits consistently without having any suspiciously accurate judgment about when the price will peak.
Make the odd deliberate, but plausible, loss.
>
> and I want to use this to get rich on the stock market. What is the best way to invest so that no one suspects that I'm doing something fishy ?
>
>
>
Be careful to avoid multiple investments which would have required you have insider information (in the absence of a time machine). Insider trading is illegal in many places and consistently seeming to have the inside track on private deals will make you look suspicious.
The authorities (and jealous investors) will be watching some deals more than others, so avoid high profile deals.
Also consider if you should invest directly in the stock market.
Again, depending on what "near future" means, choosing investment funds, rather than stocks, may be a better route. These avoid the problem of being a shareholder (and directly recorded as one), making it harder to target you as an insider trader.
Buying and selling shares is a public activity that's monitored closely. Perhaps better to e.g. act as a venture capitalist (depends on how far you can see into the future).
Holding stocks for a long time is a good strategy. Picking stocks when they're low and you know that (eventually) they'll rise is the ideal. Some people will call that luck, some will call it patient good judgment, but no one will think it's suspicious. This of course only works if your window is sufficiently far into the future to make that workable.
A "normal" investor will typically concentrate on one or two market sectors. It looks like expertise when you consistently pick winners in e.g. mining and concentrate on the mining sector. It looks like you're getting information from private sources, maybe illegally, when you can consistently invest successfully in different sectors.
Don't cherry pick the most profitable deals. It's tempting to do that, but it again makes you look like you're getting inside info. Simply pick deals that provide a solid, but not necessarily spectacular, growth.
Spread it around. Normal investors spread their portfolio around so as not to have all their eggs in one basket. You don't really need to do that as you have info from the future, but if you keep making successful everything-on-one-play deals you'll attract a lot of attention.
Do things that normal investors do : set stop-losses to trigger auto sells on stocks if they fall or rise above and below levels. Pick sensible values even if you know they're not relevant. This behavior makes you look look ordinary.
And, again, allow some plausible fails is desirable.
Spread bet. So this, as it, again looks like you're simply a cautious investor with good judgment who *is* afraid of loosing and has a backup plan. You don't actually need backup plan to minimize loss, but you do need to look like you do.
Avoid having friends who are in investment firms and banks. Nothing looks more suspicious than someone getting rich on a string of successful investments than someone with a string of friends in the banks and investment companies that handle IPOs and mergers and bank loans. If you have friends like these, never talk money with them. Never. Let's see the investigators get past "No, Bob has a rule - we're friends, no business talk, just fun.".
Last trick : do lots of "normal" market research. Just in case some nosy twerp starts asking questions, you want to be able to say, "why, I'm successful because I spend a lot of time researching companies and markets." Computers, accounts (you actively use !) with investment research firms that sort of thing.
[Answer]
Set up a brokerage firm.
Then you get paid to advise your clientele.
With the time machine information, it becomes straightforward to know how to advise your clients with a mix a both winners and losers that are designed to slightly outperform your competition. This will allow you to collect commissions on both winning and losing trades in a large volume.
More subtle than playing the market directly, but longer term more profitable and lower profile. Invest in computer big data and neural net learning. This will provide a longer term answer for outperforming markets, should the need eventually arise.
[Answer]
Just claim predictive models/ai/supercomputers/string theory/whatever buzzword you want. Currently there a some hedge fund investors who we know nothing about that do just that. Investing no longer involves a financial degree.
[Quantum Group of Funds](https://en.wikipedia.org/wiki/Quantum_Group_of_Funds)
[Renaissance Technologies](https://en.wikipedia.org/wiki/Renaissance_Technologies)
[Answer]
Well, I'm not an expert in the stock market or other financial rigmarole, but I've thought about such things myself often enough to have a solid answer. The best way to not get caught doing anything is to not be obvious about it.
So first of all, obviously don't pull this trick by investing in any companies you or anyone related/acquainted with you may be otherwise professionally involved with - this would lead to suspicions of insider trading, time machine notwithstanding.
Beyond that, the trick is to pick a great many stocks to invest small amounts in, which individually don't make a massive fortune, but together equate to one. Further obfuscate this by picking a diverse portfolio of industries/services these companies provide.
Finally, choose, along with a diverse and expansive portfolio, multiple brokers through which to work,which further fragments any seeming pattern of someone with foresight they shouldn't have.
A bonus would be to also, when liquidating these stocks into conventional funds, place them in a multitude of institutions rather than one or a few major banks.
It also probably wouldn't hurt to have collaborators whom can further spread things out.
It's worth pointing out just for the heck of it that Heisenberg and Schrodinger would have a thing or two to say about this whole idea but oh well.
[Answer]
Don't invest in stocks yourself. Start an investment newsletter. Mix your "guaranteed" tips with twice as many random ones. The punters who buy the newsletter won't be able to tell the difference till it's too late - but that's not your problem!
Use the guaranteed tips as a selective advertisement of how good your newsletter is. (There's no risk in doing that - the entire financial services industry does exactly the same thing to separate fools from their money!)
Aim to get say 10,000 clients with an annual subscription of \$100 and your income is \$1M a year, for maybe one hour's work per week. That's not "being greedy" - it's just having a nice lifestyle.
Once that is up and running, launch a "special edition" for high net worth customers with a subscription price nearer \$10,000 a year than \$100. Make sure their returns are above average (but not *too much* above average) and they will do your marketing for you, for free. Everybody likes to talk about how clever they are financially!
Note, this approach bypasses the most obvious cause for suspicion: You only need to recommends stocks to *buy*. You don't ever need to tell your punters when to *sell* them because they reached their peak. If people sell them too soon and reduce their potential profit, or hold them too long and lose money, that makes no difference to you - you get the same subscription fees either way. Of course you can time your *advertising* to show good results, but you don't tell anyone whether those results will get better or worse in future. You can't be accused of having insider knowledge if you never use it!
[Answer]
# High-Frequency Electronic Trading
Long-term stock price trends are for chumps. The flash crash of May 6, 2010 lasted for about 36 minutes, during which trillions of dollars changed hands between various electronic trading firms. Even in the absence of large flash crashes like that one, there is a large amount of second -to-second volatility in stock prices, and if you could perfectly predict this, you could net millions of dollars in a matter of hours with only very limited initial capital. At these scales, insider trading is not even an issue - you're not going to buy the stock until a fraction of a second before the price starts going up anyway; it'd be equally plausible that your supercomputer AI cluster managed to predict it from trends, etc.
Depending on your specific time-travel technology, you could either attach your time machine directly to the high-frequency trading equipment and have it interact directly, or you could go back in time with a hard drive containing detailed stock market records and base your trades off of that; it's essentially the same thing.
[Answer]
Shares are bad choice. It would be much better to use Forex. And take advantage of tiny changes between exchange rates of currencies. The positions are closed within a few hours, so even with very short precognition it would not look suspicious. The factors affecting such market (except maybe insiders in central banks) are mostly beyond risking being accused of insider trading. And if you made bets on exotic currencies... EUR/USD pair is for wimps... Try betting on relationship between Turkish lira to Korean won... who knows how they should behave and must suffer from paranoia if think that your insider knowledge could be so good.
(the only extra advice is not being to good... making also bad guesses is required...)
[Answer]
The obvious answer is "stay under radar". How low should you stay?
If your time machine can see only few hours or days in advance, you would have to make your trades right before the big market moves. And big market moves usually happen after certain news breaking out - like earnings reports, merger&acquisition announcements, big deals made or gone bust. Most of those news are known beforehand to a group of individuals known as "insiders", and they are prohibited by law from trading or divulging this information to anybody. But some insiders always try. That's why all significant trades before big announcements are suspicious and authorities try to investigate them. My former company's president was caught red-handed with telling his friends and family what he wasn't supposed to tell and he went to jail for it.
"But I'm not the insider and I'm not getting any insider information!" - you say. That's right. But prepare for the authorities to knock on your door and ask you some questions.
However, if your time machine has a longer range, you don't need to rely on big market moves. You can enjoy gradual stock growth or decline. In case if anybody asks, claim a unique methodology, or a hunch, and everybody will think you are just a "normal" genius.
[Answer]
Start a hedge fund. Form a committee. Members of the committee research stocks and form recommendations (buy, hold, sell). Recommendations with a majority vote get taken. So now you have a legitimate activity that generates stock trades. You want it to do a bit better, so change one trade a day. Arrange things so that you count the recommendations, which are anonymous. Only you know what the real result is. Each day report an incorrect result. Buying instead of selling. Or vice versa.
Over time, this single transaction will give you an edge. You'll make just a little more money than everyone else. Too much of an edge? Back off for a while and let the group make all its own recommendations.
Let someone else be the public face of the group. You're just the one that counts the votes. So even if someone thinks that the group is brilliant, they won't credit you. They'll credit the people who vote. You just quietly collect money in the background.
If asked why the vote needs to be anonymous, say that it's to prevent politicking. Each person should make their vote separately. People shouldn't be advocating their position. It's in the rules. No sharing your votes. Someone who breaks that rule gets kicked out of the group. After a few early examples, you should have a group that is committed to that. After all, the group works. It must be a good rule.
The ideal would be to take over a hedge fund that already operated this way, but you might have to start your own. Recruit people who like the idea of how the fund would work.
[Answer]
Most of the answers share a common theme: don't be too greedy. If you keep your winning to a not-so-suspicious level you can get away with it.
But that's no good. What's the point of a time machine if it doesn't make you filthy rich? Beating the market only a little isn't going to cut it.
Instead of trying to win consistently a little over a long period of time, win big in a single transaction. Identify a stock that will over a surprising short period of time go from worth nothing to worth millions. Only do this once, and it will not look suspicious, it just looks like you got lucky.
[Answer]
## You'd be lost in the crowd
I'm not sure you would be detected. There's billions of people on the planet, and many of them are doing get-rich quick schemes... because they believe they work. I'd think more would look upon you with envy than skeptically. And besides, [others have made literally billions of dollars](http://www.investopedia.com/ask/answers/08/george-soros-bank-of-england.asp) without the aid of time machines, so why would anyone suspect you?
## How much makes sense?
Another thing you should consider is exactly how much is plausible on a given day for various stocks to rise and fall. Reportings like to zoom in on those line graphs because it makes a very dramatic story, but they're not often spikying around by 100's of percentage points in mere days, if [this article](http://www.investopedia.com/articles/stocks/12/most-shocking-stock-increases-falls.asp) can be used as a rough upper/lower bound.
Maybe you'll discover in your research that the amounts one can earn in a day is not so implausible to attract attention.
## People notice much less than you'd think
My grandma's neighbors once had a crack lab in their basement. Maybe it was meth. My neighbors could have millions of dollars under their mattress. Or they may not. I have no idea, and I'd bet most of the other people on the block don't either. It's not like we spend a lot of time inside other people's houses.
If you're not spending tons of cash in noticeable ways, then you won't be noticed.
## "Suspected" is not "found guilty of"
Let someone suspect, and have the way your character deals with it be part of the story. Do they flaunt it? Do they ignore the investigation? Do they get extra paranoid?
[Answer]
Dot\_spot (or however you write it) actually made a very good remark:
# Don't play the stocks. Play games of chance instead.
In the Schlock Mercenary webcomic, in the 2005 arc involving time travel, one of the characters played the stocks to make hundreds of millions from it. However, the character that brought him those stocks bought lottery tickets.
Lottery tickets are a much safer way to abuse time-travel of information:
### Disadvantages of stock trading
1. playing the stock market inherently changes the price these stocks are being traded at. This means that you buying these stocks may affect the price at which those stocks are being traded, leading to unpredictability in prices.
2. Even if you can compensate for these stock changes, there is the possibility that your trades may disrupt the market. Suppose you get a prediction that a stock will double in value in 2 days and then goes down by 90% 2 days later. You end up buying shares now, which may actually lead to other people following your example, leading to the projected rise in value. Then, you sell it all at the peak, and even do some short selling, which is again a potential signal for other buyers to sell their own stocks, which again causes the drop in value. In the end, you're not insider trading, you're disrupting the market, and the price changes become a self fulfilling prophecy. But if you hadn't sold those shares after you bought them, the market may have remained stable.
3. Making too much profit may attract unwanted attention from other people. People are always trying to find out how to make the most money through trading, and other people are always trying to figure out how to make the trading fair.
### Advantages of lottery tickets:
1. Lottery tickets are cheap. A ticket usually costs only a couple of USD or your regional equivalent.
2. Lottery is stable. if you buy a lottery ticket, it's not going to magically change the winning numbers. Likewise, if your machine can really see the future, it can indeed spot the winning numbers and they'll always be those. You're not going to affect the future beyond potentially making someone else split the pot with you.
3. Winning the lottery doesn't make you famous. In many countries, it's normal that the winner of the lottery remains anonymous to the general audience. However, being a master at stock trading is noticeable in the sector, leading to people tending to follow your lead.
4. Winning the lottery is easy to disguise as a random event. If you can see a month into the future, you can simply setup a recurring lottery ticket purchase and hide your victory as getting lucky.
5. Lotteries usually have higher winnings. A single ticket can give you hundreds of millions at once. Winning hundreds of millions on the stock market is not easy without attracting attention of the watchdogs.
6. If you attract too much attention with the lottery, there are other measures that you can do. Go into a casino, go to the roulette table and put everything on black at the right time. Or gamble on sports outcomes. Do note that sports outcomes may draw unwanted attention from unsavory types, like match-fixing mobsters.
[Answer]
Depending on how far into the future you can see, and how much control you have over *what you can see*, you could do whatever you want on the stock market and simply use the time machine to watch for blowback on yourself.
Keep tabs on your own personal life as well as the market details. If you see yourself getting an unwanted amount of attention in the future, change your strategy to avoid it. If you see yourself getting arrested, use the machine to find out how the authorities got onto you (and what they think you did) and then take steps to derail that investigation or set up evidence that disproves the allegations.
(Should be easy enough, because unless they're accusing you of using a time machine to predict the future, you're most likely innocent of the charges anyway.)
[Answer]
## Real Estate is your friend.
Heck, it might even make you president . . .
I assume that you want to make your money fairly fast (otherwise this question is too easy). The beauty of real estate is that single deals can make you hundreds of millions or even billions in a single deal, and no one blinks an eye. With a time machine you can easily buy a piece of Orlando farmland in, say, 1960, and wait for Mr. Disney. Or you can head to 1920, buy a little ranch in Texas, somewhere around Permian, I think, and wait for the oil drills. If you prefer a more hands-on approach, head to Manhattan in the 1930's - you can buy the whole island for a string of beads, I think - and sell in the post-war boom. And here's the thing . . . no one will suspect a thing, because fortunes are made on such "luck" all the time. About 10% of all billionaires made their fortune in real estate, and you probably haven't heard of any of them not named Trump.
[Answer]
>
> In either case, you get attention for your success.
>
>
>
You just said it yourself. You need to reduce "your success". Ideally both the "your" and the "success" part. And you can do something for the attention too.
# Don't be greedy.
As you stated, it will be your success that attracts attention. So, in the beginning, sell stock at more than you bought - but less than the maximum it will attain. Be good, but far from perfect. Do not win 100 - win 150, lose 50. Ideally, win many small operations, lose a few big ones.
# Distribute the "blame".
When you have money enough, hire several consultants and get lots of advice from them. Then follow exactly, but *almost* only, their good advice. Set them up for failure - when one of them won you too much, too long, start following their bad advice also. At that point, switch to another consultant. Apparently, it will be *them* that are "too successful" - and even then, none of them really too much.
Sometimes, do not follow advice you know to be good, and lose the possibility of raking in millions.
# Distribute the happiness.
*Sell* advice to third parties. Not too good advice, but good enough to get good business.
# Act.
Occasionally, buy some stock that is going to fail spectacularly and berate the mysterious consultants that guaranteed it was going to rise. Try unsuccessfully to sell the stock. Watch it rise back to the previous levels and more. Act as if you knew that it was going to soar and deny you ever cursed the brokers that suggested it. People will immediately slot you in the "lucky asshole" category, and even if you earn millions, they'll be sure that you're also losing a bunch, and simply hiding it well.
[Answer]
I would take a "hide in plain sight" strategy:
If your time-machine can see 1 trading day into the future...
## Start a day-trading blog.
Subscribe to several financial newspapers. Important: these must be paper subscriptions, to avoid leaving a digital trail of what you're going to do next.
Your typical day might run like this:
Every morning, read the prediction off your time machine, then search your newspapers for positive articles that happen to match stocks that are going to go up (vice-versa for negative stories). Write a blog article about the stock you just read about from the paper. Post lots of charts, technical indicators, quote IBD ratings, etc. Trade the stock. When too many people start following your blog, take a losing streak to shake them off.
If your time-machine can see a month into the future...
## Hire some people and start a monthly newsletter
Typical month:
* Ask your staff to come up with trading ideas by the 5th of the month
* Give your staff a deadline of the 10th for draft articles and the 15th for final articles. The 15th is the day you send the newsletter to print. Place trades on the 16th.
* Read your time-machine prediction on the 5th the month when you are reviewing the staff's ideas (you do not tell your staff about this)
* Find ways to make sure losing articles don't always get published
Read the biography of William O'Neal, founder of IBD.
] |
[Question]
[
Obviously I know that everyone who is living there is going to want a house but what comes after? Do they build a butcher’s building next or maybe a blacksmith’s building? And what comes after that? Is a town hall only built once a village has become a town? Basically I want to know which buildings come first and in each successive step until you get to a city. Also, I’ve been looking at fantasy maps and the buildings all seem to surround a central spot that usually has a statue or fountain in it. Is that where the buildings first started?
[Answer]
First is a little house, next to some sort of resource:
Farmable land, a stand of good wood trees, a nice fishing spot, whatever.
If the spot does not have good water, a well will soon follow. Of course, the spot needs to be really special for a settlement to start without a pre-existing good water source. And wells do not easily facilitate unlimited growth, so most villages start next to a river or around a fountain.
Goods are traded with distant neighbors or at the even more distant regional marketplace. Still, footpaths are established between places worth visiting. This starts the initial road network, along paths of necessity but along easy walking slopes in good terrain. Fences appear around valuable spots, and along the footpaths. You don't want the visitors to raid your orchard, and oh the headache if your sheep wander off onto the neighbor's pasture!
The population grows, the house(s) expand. They get tired of carting their produce to the marketplace over the hills, so they setup their own market stall. People start visiting this market, footpaths become cart-tracks become roads. The marketplace starts selling other settlements' produce. Some more permanent shops are set up. People build their houses nearby, as all that traveling is too much effort.
All of these people buying and selling want a place to eat, drink, socialize, so you get a tavern or similar gathering spot. The religious types complain about the louts frequenting the tavern, so they set up a church.
Everyone starts having kids, and the kids should not be stupid. So, lets build a school.
Now you have a rich community with lots of victims and valuables. Crime both internal and external. Better set up some Law.
The new sheriff keeps the peace well. More traders arrive, more settlers build houses. Growth everywhere. People start storing goods in bulk, and manufacturing new goods from those. Mines might be set up to satisfy the needs of this industry.
The village becomes prosperous, but the people start complaining about the few Elders wanting to run the whole show. They want a say in what happens, too! It doesn't help that by now most people have gone through school and can read and think for themselves. So, setup a town council. Hello politics! Hello large town tying to become a city.
The growth of a tiny settlement to a small village to a town to a city is a slow, organic growth system.
The *extreme* majority of such settlements die out, or stagnate at a smallish size, or are enveloped by their more successful neighbors. But the few that are truly successful will grow and become huge metros. And almost *never* is this growth planned in advance, the growth just seems to happen and then retroactive repairs to layouts get made to fix the silly mistakes of your ancestors. And some historical mistakes never get fixed, like those narrow, twist cobblestone streets of Europe. And some require gargantuan projects to fix the problem, like London's sewer and underground railway system.
About the specific question of a fountain, statue or square very often forming a centerpiece for a village:
This would almost always be near the center of the village, where two or more big roads cross, thus a place that everyone passes by. In those cases where this feature is in a clearing or square, that would be because that was the location of the Marketpace, when the market was still an open-air feature. Later the surrounding buildings became shops that absorbed the function of the marketplace, leaving an empty spot that was nonetheless a focal point of everyone's activity. A perfect spot to put up a statue!
[Answer]
**Fence**, or wall first, to ward off wild animals zombies (if any).
**Community social place**, to socialize especially while everyone busy building their own house, they need to rest somewhere, and socialize while resting. At first, it is a firecamp, and it may gradually grow into a tarvern.
**Road**, as people need to move around. So, the road will make itself (grass dies, make a trail).
**Water sources**, like a well, or a moat to lead water in farm.
**Farm**, as people need to eat. However, it might not be the case if every family want their own farm instead of collective farm.
So, collective farm, or 1 farm for each family.
[Answer]
**Assuming a group of settlers came to an area with no prior settlement with the intent of settling down**
Firstly people will need places of accommodation. So house constructions will start first with lower priority. While building the houses people will also need food and water. So at the same time people will plow the land to grow food and build wells,drinking fountains. Villagers will need somewhere to store the game they hunted, berry they picked and the grain they harvested. So they will also build a barn. These buildings are not queued but built at the same time with barn and well being the priority. Houses will be built in a longer time as storing and protecting the group's resources is a priority and the villagers can acommodate in the barn until the houses are built.
---
After basic need production chains are secured people with different professions might move in or villagers might find time for other professions such as tailoring, blacksmithing etc. That also depends on natural resources and trade opportunities with other settlements.
---
Building for taverns, especially Inns and brothels will be built if the village is on a trade route or a lot of traders visit the town.
---
Also regarding the last question of yours, the square with fountain/statue is most probably where the village started if it is the only square like that.
[Answer]
Depends. The technology level, the reason for moving, the resources available, culture and traditions, threats, geography, climate... In some cases, the resource extraction could be the only building. In some, the communal house complete with storage, cooking, and sleeping functions. One thing for sure, it's not a government building of any kind :)
[Answer]
Unless otherwise specified the settlers have domesticated animals for food and other uses and have also developed agriculture. This means they would probably prioritize as follows:
Immediately upon arrival;
1. Temporary animal pens;
2. Simple basic shelters;
3. Land clearing for food production (also produces fuel and construction material. **PLUS** construction of stockades and permanent animal pens- because the first process produces the material needed for the second as it progresses.
4. Permanent Shelters;
5. Barns,stables and other food storage and processing buildings;
6. Basic civic and/or religious buildings;
7. Specialized trade/crafting structure (forges, potteries, butcheries etc)
At first the village's growth is defined and limited by the need for protection and water. So a defensible site near a watercourse or spring initially sets the boundaries of the community.
As the population rises the community becomes large enough to outgrow these initial starting conditions. And this introduces the need for more planning and organization.
8. Sewers/drains & paving (at least at key points), warehouses/storage sheds, formal market squares & shops plus government buildings (depending on the type of government) civic halls/courts & jails, the rulers home etc plus higher walls enclosing a larger area with at least some degree of 'town planning' to regulate what work can be done where.
[Answer]
If your village-to-city is build according to plans to grow into a city, it follows other rules than a village that grows and grows and people find they are in a city one day.
**The accidental growth.**
A few families build houses quite near each other, maybe because the ground there is higher than the ground around in a low laying area or because there is a natural well or a small stream that provides them with water.
Once there are a few houses and the owners do well, they will likely build smaller houses, or add extra structures to their property, to house the people working for them.
I guess the first people are farmers, as that is what I am most used to, but fishermen and trappers/hunters could start villages as well.
When there are enough people to make a start of a village, more people may come in. I would say 'will' except that in many cases it did not happen and it would stay a hamlet, grow into one big farm or disappear completely.
Crafts people may have been part of the farms or may have had their own buildings as soon as there was enough of a village to give them enough work. And the blacksmith was likely one of the first with a separate dedicated building.
When there are enough people in a little village, it is not unlikely that a church/temple/mosque/whatever is build so the people have a special space for their religious services.
One of the houses may start selling tea and coffee, beer or wine (in places where those are drunk) or even stronger spirits, and grow into a tearoom, pub or kind of place where people can also stop overnight, call it a simple kind of hotel but in many cases not called that. (In Europe hotels are a rather recent addition, in the USA and all other countries that were filled with Europeans at that same time or after, hotels were there almost from the start.)
With enough people, trade started to get a structure, in a shop or a regular market, and with more people more trade and more shops (or a bigger market) came.
In the parts of Europe I am most familiar with, villages would stop growing once they had a certain size, as they covered the need of those people near them and an other village would take care of those a bit farther out. Some villages would be picked out by the lords of the area and given extra rights, so they could charge more taxes but for those could offer more protection to their people, often building walls once they grew over a certain size.
Not all those villages grew into walled towns, some failed and disappeared, others stayed and did not grow over the size of a small town.
Villages growing around castles or religious buildings or army camps have also grown into cities.
Once the size of a small town, buildings would start to appear that had no actual need for living or trade, like guild houses and city halls. This can be besides the old village but if the first farms have stopped being a farm those buildings may well be taken down and the space used for other reasons. The first huts of a trappers or fishers village have even less protection.
The more a small town succeeds, the more people come and often the towns build up all the ground within the walls and start to spill over. Then the town had to build new set of walls, bigger, and often take down the earlier walls once the new ones are secure.
When warfare had gone beyond protected cities and castles, the cities stopped with putting up new walls and most of them took down the last set to have some more space.
Depending on the location, a cathedral would be build and the town would be called a city. Around that same time a university might be started and of course enough schools that all boys from rich families could get lessons.
Again, by the time people spread in the USA, school would be available to (almost) everybody, not just to the males and not just to the rich, but by that time most of the current cities in Europe were established.
Of course when the society changed, like it did with industrialization, the smaller villages and small towns would grow again, mostly with 'random' growth but a lot of factory owners would have housing build for the people working for them, often small villages grew into towns because of that.
And sometimes cities were planned to house the people who did no longer fit in the villages and towns, and older cities, when too many people wanted housing and there was not a lot of space to build there anymore. But that brings you into the next part of this answer.
**Planned cities**
Most planned cities are relatively young, but there have been cities before the start of written history and some of those, from excavations, seems to have been planned rather than grown.
Planned cities can be started with any of the building, but again a start with series of houses and/or farms is likely.
Extra buildings can be any kind, a community center combining school, a shop or even a doctors office.
Most planned cities will have a certain size they expect and they might have city squares and central buildings from the start or they might be build from an edge and grow around a center, which get purpose when enough of the city is build.
Also see the difference between a planned city and a new suburb in the USA (and other countries) where the new residents have to have a car and are basically cut off from the center of the city they 'belong' to, with long distances and filled motorways. With malls out in nowhere with nobody living within walking distance and even the old city centers often falling in ruins.
**How to make your own village or town**
For a city growing in a book or game, or an other thought up environment, you can use whatever building suits your plans.
Consider the age and the environment the town grows in, combine whatever buildings your story needs and can be explained to the age you set your story in. The most recent of build cities are very new now. In the Netherlands we have several which are no more than 60 years old and most of their buildings way newer. In each science fiction book that has build cities you will find future ideas how cities will grow.
If you have a new city on a new planet, you may well mark the place of the 'first landing' as the center of the first city they build. But it may take a few generations before the 'fountain of the first landing' is in the middle of a city, as new societies need time to grow and earn before they can afford to build the cities.
[Answer]
For most of history, there were very few single-use buildings. A large majority of people were farmers, and also would do other crafts in their homes during their downtime. Most craftsmen worked outdoors, only the richest would work inside. Potters and blacksmiths would have their kilns and forges just outside their home. Most everyone would do some of their own textile work, spinning and weaving doesn't take much strength and can be a done a little bit at a time when taking a break from other work, and so would not warrant their own buildings.
If you don't count awnings built over a forge or kiln, which I wouldn't since they wouldn't have walls, the first non-residence buildings will be barns if the community is raising much livestock, granaries, or will be communal property like a church.
[Answer]
## There is no Guaranteed Sequence
There are many reasons for a town to be formed. Some towns begin as a farming community, some as mines, some start off as nothing but a port or way-station to facilitate trade, some start off as communes of people who practice the same craft, some start off as remote monasteries, some start off as slave plantations, some start as suburbs, and some start off as a fortress placed in a strategic location.
The buildings you can expect will also depend a lot on the tech level at your disposal. A modern town will generally import a lot more of its basic supplies so you will get a lot less simple workshops. A less modern town will not have anything like a water sanitizing station, power grid, or paved roads like you tend to get pretty early on in more modern towns. A stone aged society may perform a lot more of their trades in open-air spaces than later civilizations such that you may not get buildings at all where certain crafts are performed. A future tech town started on Mars will have very different needs than even a modern town has.
Because towns can be formed for so many different reasons under so many different circumstances, the order in which buildings are made can not be put into any set formula. What may be the first 10 buildings in one town may not be seen in another town ever. In-fact, you can not even assume it will begin with a house since many towns start off with a resource, industrial, or military building that people then settle around later for convenience.
So, you first need to ask yourself: **"When, Where, and Why was this town founded?"** and that will inform the order in which you need to build things.
[Answer]
Introducing:
**Redfrogcrab's Universal settlement development plan**
A basic outline for the development of any settlement for any setting, whether the town is built on the soil of an alien world in the distant future or in a mystical forest in the time of knights and dragons
Phase one: most likely, your settlement with start off with a few homes built around or near something deemed important. Examples: a Science outpost in the times of space flight, a medieval inn, a gold mine in the time of cowboys. crops and other food sources will be brought along as well because we all need to eat. Homes would be built around a central location as a place to gather and meet. Only bare-bone necessities in this phase. things that settlers need and can't get from the environment at this point will be imported.
Phase two: this phase is about population and economic growth in your settlement (most likely from migrants) and the expansion of the facilities and skills there, mostly stuff like a blacksmith (or fabrication facility for sci-fi settings), place of worship, local law enforcement building, a general store; pubs and other recreational buildings are an additional addition to this phase, the central plaza is paved and residents move out away from the center, with markets replacing them. local food production would also be ramped up. This phase could be fused with phase one as well. What you are exporting at this point matches what you are importing.
Phase 3: Congrats; your town has gained a spot on the map, more and more people have come in and settled down, the central plaza is bustling with people, paved streets, massive farmlands, and more specialized "commodity" stores (or stores that specialize in selling non-essential goods like paints, flowers, specialty foods, glassware or textiles) have appeared. Maybe a fountain or statue commemorating a local hero or important event has been erected in the town square. Your town will probably keep growing unless whatever brought your settlers there goes away and a new thing to keep people coming isn't found. This town at this stage is primarily self-sufficient and exporters of goods.
Other things to consider:
Ghost town: Everyone in the settlement have either left or been killed, something happened in history that stopped growth and the population is down to near zero
Geographical factors: consider the geography of the region that's being settled, ocean towns will be centralized on the port while Prarie and desert towns will be centralized on the general stores and trading post. Resources also play into effect, what you can use to build and what you can sell in the environment can have drastic effects on the growth rate(how many people are being born or coming in-the amount of deaths and people moving out), longevity (from the first settlers to the last), and pull of a settlement (how much do people want to live there?)
Tech level: it's easier to build and grow a town when you have access to modern technology and above, Rome wasn't built in a day but with high enough tech and enough will power you could build it in an hour
Sci-fi/interplanetary factors: If: breathable atmosphere then: individual buildings. If: airless or non-breathable atmosphere then: Interconnected air-tight modules heavily shielded from radiation or buried underground around a water source or other important resource.
I use this flow chart for my towns, cities, and colonies for whatever I'm writing, fit it to your specifics. It also doubles as an in-universe classification system for the development of settlements.
Hope this helps
] |
[Question]
[
I have a community in a freezing polar region who **occasionally** resort to cannibalism to survive. This only occurs when **all other food reserves are exhausted** due to story based logic.
Each year/few years they designate a number of people to be *standby* victims. This is to avoid potential conflict over killing someone in power's sickly grandmother or favourite lover etc. If these unlucky chosen individuals are lucky, they don't get eaten and they get taken off the roster and live to eat another day, others replace them in the following roster slot. If they are unlucky...they get eaten. (Extra clarification: They have no say in the matter... while they are on the roster.)
* the roster time period does not have to be a year. It could be a number of years if it makes more sense.
* the roster system is not the question.
* the security of these individuals is also not the question but can be taken into account. (Edit - clarification these victims have no say in the matter. If they need to be tied down or come willingly is story based logic)
* how victims are chosen is out of scope.
**Would the community's dietary requirements during a harsh polar winter require these *standby* victims to be fitter or fatter?**
---
My *initial thoughts* were that: in these extreme situations the community would be needing to replace their own depleted fat reserves and would therefore require/prefer their emergency supply to have higher fat content rather than lean muscly meat. Therefore I thought that these sacrificial victims could be living a life of 'luxury' for their duration on the roster (with their potential death looming over them) . During the good years, as well as building up the communities fat reserves, they would also try and add in a living fail-safe fat reserve. Build up their victim's fat reserves while the hunting season/s are good and plentiful, **in case** of a future bad season?
---
Main Edits:
(1) Thanks for the comments and answers so far. They are all valid points that I had already tried to take into account. I was trying to avoid story based and opinion based question so **tried to narrow down the question to the crux of the matter**. If you were the polar based cannibal, would you eat the fatter or skinnier morsel on offer.
(2) For those that need extra information...
First off: this question is not on the logic of the roster premise or who and how those on the roster are chosen. young/old/powerful/weak/childless/grandparent that is all good moral and ethical story stuff dilemmas. I am trying to figure out: of those in the roster group do you select by amount of fat or those that are fitter (as considered in modern day western culture).
* Those on the roster have every reason to help ensure the community is ready for the winter, so that that they can survive uneaten. Many do survive their term on the roster. And if the system does end up having a fattening up program, they could *potentially* get out ahead at the end of their term. These days it's not often that they lose out on the deal. Back in the day? Totally another story.
* The roster system was designed to stop infighting over who was to be killed. The settlement was hastily constructed and didn't have enough resources. As logic dictates, unplanned cannibalism took place, feasting on the perceived weak and ill. Illogically, the military elite did not want their own injured brothers and sisters killed and eaten, they would rather try save their comrades and eat the non vital civilian members of the group. Over a number of years the roster system was developed to ensure that those in power had no fear of being eaten or dying of starvation. **Roster selection criteria has changed multiple times over the years and is dependent on story based logic.**
* Food is certainly preserved in the frozen wasteland they call home. They do plan ahead as much as possible. Occasionally they are sh%t out of luck and all their food reserves are used/ruined/stolen/spoiled/poisoned/ice-shelf fallen on top of it/ whatever you can think of. The roster system is still in place, mostly by tradition, but partly out of fear of what happens if the worst case situation happens. **How the community at large and those on the roster react to finding out they are about to actually make use of the roster system is story based logic.**
* There is actually nothing stopping a community member from volunteering to prevent a roster member from being killed (but this happens even less frequently than the need to utilise the roster!). Those community members that die anyway during a harsh winter, will obviously get eaten before the Roster is used...they are cannibals, not complete imbeciles!
* This is obviously not a stable or long term viable settlement system.
* This is not Earth.
* Thanks again for the further comments and answers. Lots of food for thought. I hope I covered everything.
(3) Choice of answer. It was hard, as the popular answer is the most logical that would apply in most normal situations/settlements. I already knew this but created this settlement based on the extreme end of the 'normal' reasoning spectrum. Humans are illogical. My community had a very abrupt introduction to the environment and formed traditions upheld by a very strong military force. I was already going to be choosing the 'weaker' undesirables for the roster while keeping those with specialist knowledge alive, at least at first. I have dropped the idea of a *purposeful* fattening up program but need the roster to stay put even if just for the initial start up of the community.
The chosen answer was selected because it did actually answer the question as stated, as well as answer the reality check part of the question. Even though you *should* eat the fat one for dietary purposes, logic dictates you start with the thin one anyway.
There were actually two answers that stand out as saying this. However, the selected answer had the extra bonus of mentioning the social acceptance of the *need* to resort to cannibalism.
Thanks again for all the input. It has all been taken on board.
---
I feel a DISCLAIMER is needed: I in no way endorse cannibalism as a long term solution in make-believe or real life. I withhold judgement on real life emergency situations until I am ever in such a position myself.
[Answer]
# The [Custom of the Sea](https://en.wikipedia.org/wiki/Custom_of_the_sea) applies
Though in your case it's the custom of the ice.
The custom of the sea allows the survivors to agree to resort to cannibalism to survive a shipwreck without the usual penalties associated with killing (and eating) someone on return to civilisation.
First you eat those who are dead or dying anyway. Then you draw lots. This drawing of lots is important, it makes it fair on all those involved. It so happened that the passengers tended to lose first, followed by the junior crew, but lots were drawn.
Your society is drawing the lots in advance and skipping the stage of eating the already dying. Though you have declared this out of scope it is highly significant that you may be eating the healthiest to try to save those who may die regardless.
# Eat the fat one
A couple of links but we'll go over the key aspects
<http://www.icetrek.com/polar-food-and-diet>
>
> Butter
>
>
>
Lots of butter, explicitly stated, along with other high fat food. Cheese, chocolate, nuts
<https://news.nationalgeographic.com/news/2013/10/131025-antarctica-south-pole-scott-expedition-science-polar/>
>
> Saunders and L'Herpiniere will consume almost 6,000 calories a day—a combined total of 1.3 million calories for the trip. The largely freeze-dried menu includes porridge and cream for breakfast, energy and protein bar snacks washed down with hot carbohydrate and electrolyte drinks, and chicken curry with added fat for dinner.
>
>
>
Note the amount of fat included in both sources. It's actually really hard to physically consume enough calories while being that active. You need to seek out the highest concentrations of calories you can. You can't use large quantities of low calorie foods, you won't be able to eat enough. Butter comes in at over 700 calories per 100 grams. **There's very little that can come close to pure fat at around 900 calories per 100 grams.**
---
However it's reasonable to suggest that the skinny ones will already have died before the fatter ones agree that it's time to start eating people. So in practice you'll eat the skinny ones first.
[Answer]
This practice makes no sense.
There is no reason to do this, in the Arctic you can store food nearly indefinitely, they should never be be planning for starvation, it should only occur in extremely rare emergencies (like a fire in the food stores). If there is enough food to fatten people up there is enough to store, keep in mind we burn most of our calories just keeping ourselves alive. There is a reason cannibalistic societies occur in the tropics (and mostly islands).
We only fatten up livestock this way because they can eat things we can't. Anything that can be used to fatten up your victim could be eaten instead, feeding it to a victim is actually wasteful as it uses more food than it produces.
If you have enough time and extra calories to fatten up victims you should not have victims in the first place.
As an alternative if scarcity is an issue they should be sending people out on high risk hunting expeditions, which will tend to either bring back food or reduce the population. This is what real communities do.
[Answer]
There are many problems with your scenario, human meat is not worth what is put into it. So the food these people consumed is of much more value than their meat.
Relying on and planning for cannibalism to prevent starvation is not a good survival strategy for any community and is inherently unstable and that society is heading for collapse, so we'll set that aside as well.
High fat is the way to go for the protein since it contains over double the amount. It's unhealthy if eaten all the time, but the best thing in times of famine.
[Answer]
**Eat the fit one**
In a polar context, fat is a key for survival. A fat body protects from the cold, and helps survive the hard times without food. Think about animals stocking a lot of fat before winter.
So the fat ones are the more likely to survive extreme situations like a long period without food. They should eat the fit ones, who have more risk to starve to death quickly during the famine.
The fat ones will have more chance to reproduce and have children, when the fit ones -who know they will be sacrificed- should not have kids (because they won't be able to care for them).
On the long term, the genetic selection will increase the percentage of fat people in the population, giving them more chance to survive new famine episodes.
[Answer]
**Eat the old ones**
The old ones can't work that much any more, so if they get to eat as much as the rest then they might just get fatter. On the other hand, it is also more likely they get ill, and they would die anyhow. You'll need the young people - whether fat or skinny - to replace your population.
On another note, I'm not sure "fit" in a polar region means no fat. The fittest can hunt most and so they get to eat most in times where game is not scarce, be able to store most fat, and it might not necessarily slow them down.
] |
[Question]
[
I've considered making a [shared world](http://en.wikipedia.org/wiki/Shared_universe), a world with a setting that can be used by more than one writer or worldbuilder. I have a basic story planned out, and it has certain requirements of the world's geography, natural and anthropogenic history, layout, climate, and one or two other minor things. All of these elements are necessary for the story to make sense.
At the same time, I think that this world could be used by other authors for other stories, because it has some rather singular elements to it that have interesting features. I'd also like to make it open for use because I won't be able to explore all of it (for some time), and it might be cool for others to do that instead.
So, how do I make a world more sharable, even though I need to set some rather restrictive guidelines for it? Another way of phrasing the question is: How can I make a world more sharable?
[Answer]
**If you are creating a world for joint use you should write the *meta* story first.**
This is essentially the history of the world and the characters tend not to be individuals but empires, nations, armies, hordes and deities. There is some room for individuals but only the truly unique make the cut.
If you think of Forgotten Realms you have characters like Elminster and Volo. These are specific characters yes, and yes they have their own stories. That said they are tools to illustrate the world, they are essentially deities.
A setting is interesting when it has *depth*. You need to create many small, meta level stories to give your world it's *...feel,* to give users **not only a sandbox** but a sociopolitical climate and history in which their stories can take place.
That is the beauty of Forgotten Realms, or even a digital world like Skyrim. You can tell your own story but the world around you has things happening that don't wait on your actions.
So, if you have a specific story to tell, that's great, but if you want a shared world to be used there is a ton of content to create to make it great. (I just rhymed on accident)
[Answer]
# Focus on the Canon
Don't focus on creating the whole world itself, focus on **being the first Arbiter of Canon.**
The Arbiter's job will be to integrate into the Canon (literally that which is true) the world building background (places, races, people, myths etc) written by other people, to fix the discrepancies (or ask some of the authors to amend them), to **check if everything is in place**, to fill eventual blanks and dissipate doubts.
You might also find the time to write actual stories yourself, by delegating other contributors to act as arbiters.
# Orion's Arm
Check out the [Orion's Arm](http://www.orionsarm.com) worldbuilding project which I would say is the canonical shared world example.
It works as follows:
1. There is the 'Canon' which specifies what is taken to be true in the setting. It may include stuff like maps, languages, locations, races etc. The Orion's Arm Canon has been built up over time and has been subject to a number of revisions. One important aspect of the Canon is the *timeline*.
2. There is the Encyclopaedia Galactica which accepts user generated content submissions (e.g. for new planets, nations, tech, politics etc) that fit within the Canon. These are reviewed by the community prior to inclusion
3. There is the Future Voices e-zine which accepts works of fiction and non fiction set in the universe.
I would suggest you follow this principle and define a Canon which meets your criteria to enable your key storyline. Those aspects of the world which most affect your story would be the most detailed, while peripheral areas would be more sketchy and ripe for others to contribute to in the first instance.
Within your Canon timeline, define some pivot points (major battles, birth of key figures etc) from which alternate timelines can be extended, to allow what-ifs to be conducted by others. Clearly identify these and invite ideas for alternative timelines from that point.
The contributions page at the Orion's Arm website has more details.
[Answer]
**If you build it, they will come.**
Honestly, I don't think it's that hard to build a world that other people want to explore. All you really have to do is make one *you* want to explore, then write whatever stories you want to about it. Unless your universe consists of a single mind and only lasts long enough for it to think "Oh, not this again", or some similarly small setting, I don't think you'll ever be able to talk about *everything* that happens. However, there are a few things that I have noticed really helps things out:
1- **Be vague**. Like, really vague. If you can condense a two-page story into a one-sentence summary, you've probably given someone enough room to write an entire novel, or more. Just look at the line "You fought in the Clone Wars?" from Star Wars: to my knowledge, it inspired at least two movies, two animated series, at least four video games, and I'm sure countless books. And that's not even counting all the fan theories that must have been flying around before the prequels came out. Many of the fanfiction I write works well here, where there are gaps in the story begging to be filled. This goes hand-in-hand with my second point,
2- **Overshare**. The Clone Wars had *no* importance to the plot of that first Star Wars movie; they were over, and because of rule #1 no one knew what effects they'd had on the galaxy. But like I said, it was something to jump off from. This is pretty good advice for any world: don't use everything that you mention. If you use everything up, not only is your world going to appear small and lifeless, but there'll be no room for anything else to happen. This also works with my third point,
3- **Leave loose ends**. Do you know how aggravating it was when Halo canon stated that SPARTAN-IIs only wore powered armor the last year of the war? And how equally aggravating that the author who introduced the SPARTAN-IIIs also killed all of them off? Both of these facts were stretched to their breaking points in other stories, because everybody wanted to use the cool stuff. Thus, you should avoid wherever possible the bookends of time on your most interesting elements. If there is a cool war, either don't describe how it started/ended, or give it a good century or two in between so people can write stories about its battles. If there is a great weapon/machine, make sure your heroes don't have the only one (or if they do, make sure there are equally cool knockoffs available). Many stories deal with the beginning or end of something, but you should avoid whenever possible doing both.
4- Now, this one is more of a personal belief, and that is **don't worry about it**. The last thing you want to do is compromise the heart and soul of your work of art by trying to give other people a way to tack onto it. Stories should feel to their creator as if they already exist (see *Leaf by Niggle*); if you're not exploring this world as much as your readers, and are simply cobbling it together as a means to an end, it's going to show, and it's not going to be good. If you create a great story in a world that you love for itself, rather than for its capabilities, then other people are probably going to love it too. After that, if there are more stories to tell, they should come naturally.
[Answer]
**Do the parts other people don't.**
If you've read a lot, you'll notice that there are certain things that often get missed out:
* religion
* *global* politics (single countries are often worked out, but global interactions are often missed)
* ancient history (again, recent gets done; way back often doesn't - but ancient stuff influences the present, so do it)
You should make sure these bits get done; that adds attraction to your worlds because people can write like they always have without those bits, in the knowledge that they're still in there.
**Do broad scope, not specifics.**
This has been covered in other answers. Your "characters" are *entities* not *individuals* - and big entities at that. Design governments and their attitudes, but don't design the people in them; design countries, define borders, but don't design how they're guarded or the migration rate.
[Answer]
**The future of your world is dictated by its past** so by designing the world's past, you can set it up to a specific set of plausible futures. If the design of the world is so restrictive that it can only have one possible future then not very many people are going to use it. But, it sounds like your world is broad enough to provide many niches of storytelling for other authors to fill in.
As long as there are plenty of niches to fill in the world, there shouldn't be any problems with making it more share-able.
[Answer]
**Make it shareable by posting the underlying ideas and stories**, basically make your world open-source. There is a strong culture of this kind of sharing in the Open Source Movement. Programmers write code then share it under a particular license. Which license they choose determines how others may use their code and obligations placed on those users if they make modifications.
Sharing the ideas, maps, and narrative of a world is easy. Just post a zip file somewhere containing all your notes. If you decide to use the open source model for sharing your world, then you get to choose a license ([of which there are many](https://en.wikipedia.org/wiki/Comparison_of_free_and_open-source_software_licenses)). Here's a couple options for licenses:
[GPL-2](http://opensource.org/licenses/GPL-2.0) - The Genergal Public License requires anyone who uses the code/world to contribute changes in the code/world back to the community. There is no such thing as a private world under the GPL. This requirement fosters considerable collaboration on a project. (The Linux kernel is under GPL-2 as are many other projects.) The GPL also requires that any derived works also be licensed under the GPL.
[MIT License](http://opensource.org/licenses/MIT) - Unlike the GPL, the MIT license clearly indicates that a user can do whatever they want with the world/code. They can sell it, make changes to it, basically whatever they want without regards to the authors intent or will.
[Creative Commons](http://creativecommons.org/licenses/) - The GPL and MIT licenses are specific to source code while the Creative Commons can be applied to a much broader range of creative works. Withing CC, there are six different licenses that can be chosen with this [helpful picker](http://creativecommons.org/choose/).
Which license you choose will determine how the community around your world will operate. While you may not need to explicitly state a license, the basic idea of stating how you intend the world to be used still applies.
[Answer]
Ensure that the restrictions are part of the attraction of the shared world, in other words that they *are* (or are bound up with) its USP.
So for example if you consider the world of *The Matrix*, and take away the restriction that humans are held captive by machines and therefore really can't win even when they think they escape, then you've taken away any point of using the setting of *The Matrix*. So the world is shareable by those with an interest in sharing it, because the restrictions are inherent to the setting. Anyone who would want to break the restriction, by writing a story in which the humans win once and for all, is rather missing the point since their story represents the permanent destruction of the whole setting.
As you've realised, you can't/shouldn't create a shared world and then say "actually, this kingdom within the world is off-limits because I have plans for it, and I don't want you messing up my stuff". If you do that, then other people's work in the world becomes fan-fic because it's secondary to your needs. Which is not to say there's necessarily anything wrong with other people writing non-canonical work in your world, it's just not the same thing as a shared world.
[Answer]
One thing I have found crucial with such shared content is to have degrees of flexibility. Clearly you need a core that is well understood and doesn't change often, and flexible layers for others to work. However, what we often forget is the grey area of "almost canon" products that shape the way other people write their works, but are not "blessed."
This process ensures that everything can flex, so we don't get any crumple-zone style car crashes when people disagree. It gives everyone time not only to look at the details being brought into canon, but to actually play with them for a bit before hand, to see how it works.
] |
[Question]
[
It is the age of exploration. Intrepid European colonists have come to settle the Americas amidst a storm of interest over the wondrous materials that may be found in the New World. Unfortunately for them, the indigenous have spent thousands of years cultivating their magic, distinguishing themselves in appearance, thought, language, and most severely: power. By the time of Christopher Columbus, the gulf has become so wide that the indigenous cannot even recognize people from the Old World as rational beings - regarding them instead as curiosities and pests beneath consideration.
These unfortunate circumstances have stymied European expansion into the continent, and unable to meaningfully combat the indigenous, the colonial powers have instead sought to broker communication between their peoples in the hopes that the use of familiar language will elevate themselves in their eyes. This is no easy task, given the [usual methods](https://worldbuilding.stackexchange.com/questions/90624/learning-a-new-language-without-any-reference) for learning learning language through immersion are infeasible; intrepid linguists must observe from a distance lest they be discovered and potentially killed.
Altogether, the question stands: is this possible? Can a dedicated force of 16th century linguists learn an alien language through observation alone, given any sort of contact is likely to result in death? On what sort of timescale can this be achieved? I will accept any answer giving a historical example of any language having been successfully studied (grammar, lexicon, etc. to fluency) this way at any point in history.
**Misc.:**
* Capturing indigenous is impossible
* It is possible to remain hidden within earshot of the indigenous
* Infiltrating indigenous camps, towns, and other kinds of settlement or buildings is very dangerous
* Acquiring indigenous artifacts is incredibly difficult, even if they have been abandoned
* For simplicity's sake, we can imagine there's only one language
* The indigenous language is not too far removed from real ones
* The colonists are fielding technology roughly in line with what their real counterparts had
* The colonists are allowed to have anachronistic culture or knowledge, however
* Europe is desperate for successful colonies; the wondrous materials native to the continent are as valuable to them as modern technology would be to Rome
[Answer]
The real-life process corresponding to the requirements is learning a foreign language by watching TV shows in that language (without subtitles). This ranges from trivially easy if the foreign language is closely related to a language that the learner already knows (e.g., a Romanian learning Italian from watching [*La piovra*](https://en.wikipedia.org/wiki/La_piovra) on Bulgarian TV), to relatively easy if the languages are closely related but not very (e.g., the same Romanian watching [*Escrava Isaura*](https://en.wikipedia.org/wiki/A_Escrava_Isaura_(2004_TV_series)) and [*Avenida Paulista*](https://www.imdb.com/title/tt0209550) on the same Balgarska televizia), to somewhat difficult if the two languages are only distantly related (e.g., learning enough Bulgarian to follow football commentary of live matches), to very difficult but far from impossible if the target language is completely alien (e.g., a Romanian attempting to watch Hungarian TV).
In the 1980s, Romanian state television had degenerated to such a great extent that it went on air only two hours per day, and those were dedicated to Communist propaganda. This created an environment where everybody who could watched TV shows from neighbouring countries; Bulgaria in the south, Yugoslavia in the south-east, Hungary in the west; and even Soviet TV was watched in the east.
The point is that humans have a built-in ability to learn foreign languages. This ability is highest in childhood, but it never goes away completely; and moreover, if instead of casually watching foreign TV shows the learners do have an actual incentive, the results will be even better and the learning faster.
As for formal examples, we do now know several dead languages which were desciphered entirely by closely examining ancient texts; for example, [Hittite](https://en.wikipedia.org/wiki/Hittite_language).
[Answer]
Some people in real life speak Klingon. There is even a popular story in the internet about a couple who only had Klingon as a common language between them, and they married.
Elvish is also a con language and some people speak it.
Even The Elder Scroll's Dov language has some enthusiasts.
I doubt that Tolkien and the producers for Star Trek and Skyrim were giving Zoom classes. Somebody had to reverse engineer each one before people could use them.
[Answer]
**Is it possible to learn a language entirely by observation?**
Yes, mere observation can be enough to learn a language... but that method *will* absolutely require much more time to do so than traditional immersion.
For example, there are plenty of anecdotal examples of children who seem basically mute until suddenly showing the ability to speak in full sentences. Usually, though, those full sentences come at a time that lags years behind the normal development of their peers who've progressed through basic words, to broken sentences, to simple sentences, quite some time ago.
There might be a bigger barrier to deal with, however...
>
> "... regarding them instead as curiosities and pests beneath consideration..."
>
>
>
>
> "... any sort of contact is likely to result in death..."
>
>
>
This is perhaps the trickiest bottleneck for your story/setting; depending on where you draw the line for "enough fluency to not be killed".
If something like *"We, a Lesser People, ask your Great People to teach us your wonderful language!"* is sufficient to pique their curiosity, then you can probably reach that level in a relatively short time frame (maybe a year or so, more depending on the language's particularities and difficulties). And from there, they can throw a kindergarten-level teacher at your explorers and start a more typical language-immersion process.
If you need to come out strong with a fancy spiel in full-legalese like *"On behalf of King X of Y, heir to the Z of Q, conqueror of the R, Lord over the protectorate of S, long may he reign, we, his hired explorers, beseech thee to parlay on the matter of his vassals being deigned vermin in your lands and holdings, etc. ..."* then that will be much harder and take substantially more time to develop. The particular thorniness of the issue being that you just won't have access to much of that vocabulary when eavesdropping on farmers near the outskirts of civilization. So, not only would you have to sneak further into dangerous territory to learn the important stuff... but you'd probably need a significant time investment to learn just the basics beforehand to understand *any* of the more complicated stuff by building off of context clues.
[Answer]
In many ways, this is what the [Generative Pre-trained Transformer](https://en.wikipedia.org/wiki/GPT-3) series of AI projects is doing in practice. Feed the algorithm an incredibly large body of English text, and it leans how to converse in English.
While not exactly what you are looking for, and doesn't really answer if it is possible for a human, it does show the task is in and of itself possible.
[Answer]
If your idea was the old science fiction cliche idea that an alien civilization can learn our languages just by watching TV shows I should say that no, you can not learn a language entirely by observation.
But I remembered a good movie: <https://en.wikipedia.org/wiki/The_13th_Warrior>
where Antonio Banderas character learned Vikings language: <https://en.wikipedia.org/wiki/Varangians> just by observation.
In the movie, Banderas is a noble Arabic language speaking Muslim. I was told by an old English language teacher of mine that Arabic speaking people have facility to learn foreign languages. So, may be, there was cases people can learn a language entirely by observation.
Any way, if you are dropped into a place where no one knows your language, the written system is totally different (think on Japanese or Hebrew) and you are left there forever, well, you ought to learn your new home language entirely by observation:).
[Answer]
I cannot approximate the exact amount of time it would take to learn a language that way. However, you can make things easier for yourself by inducing some luck in your story.
And by that I mean, you can have your linguist find and listen to the conversations that are happening inside one of their school. If they have any. Where they are teaching small children to speak their language.
Or any kind of family with a toddler where the parents or some adult is trying to teach their own language to the child.
And by listening to their conversations, which are meant to teach their own language to one of their children. The hopes of learning their language and learning it way faster than listening to casual conversations are way higher.
[Answer]
Learning language is a very developmental process. It is the easiest when we are young and harder when we're older if the language's seperation points referred to as phonemes, differ considerably from our native language.
Its possible however simply because most language speakers tend to use the same phrases over and over with same filler words. You'd have to find someone who could point our nuances however.
Lets put it this way, we have translation dictionaries and europeans learned to communicate with each other.
[Answer]
As described it seems a immensely difficult task if it weren't you waved anachronistic knowledge. The colonist need to overcome several conditions basic to the learning of a new language:
**Understanding the social context:** values, traditions, institutions (political or civil) etc all that give it utility and reason to the use of language. Without it the misunderstanding might be endless.
**Sociolinguistical background:** learning a language implies social differentiation. Colonists would like to set their [sociolect](https://en.wikipedia.org/wiki/Sociolect) to the right social group and social situation.
**Learning grammar:** grammar rules might have a high degree of complexity because of exceptions adding to the learning time.
So the colonists would need modern knowledge of anthropology, socio-linguistics and formal linguistics to overcome the lack of direct contact to language use.
They would be able to perform [crucial experiments](https://en.wikipedia.org/wiki/Experimentum_crucis) when they'd hit a block to the cost of getting some junior researchers killed.
I think they might be able to form a group of children in an isolated community where they'd only speak the target code. With this they might be able to show a "civilized" face after 30 to 40 years.
If they didn't have all that anachronistic knowledge it would take a social and scientific revolution to obtain them.
[Answer]
**Frame challenge**. The whole situation can be basically boiled down to decryption of extinct language (obviously you can't speak with dead people who spoke said language), when there is no grammar textbook on said language.
One way to help this research is to find closest relatives for languages of Americas. And then use knowledge of said relatives for decryption of American languages.
It can be possible, as such relatives were found, or at the very least, were suspected to be found, see links below (maybe there are more):
>
> Dené–Yeniseian is a proposed language family consisting of the
> Yeniseian languages of central Siberia and the Na-Dené languages of
> northwestern North America.
>
>
>
<https://en.wikipedia.org/wiki/Den%C3%A9%E2%80%93Yeniseian_languages>
>
> The Eskaleut (/ɛˈskæliuːt/), Eskimo–Aleut or Inuit–Yupik–Unangan
> languages are a language family native to the northern portions of the
> North American continent and a small part of northeastern Asia.
>
>
>
<https://en.wikipedia.org/wiki/Eskaleut_languages>
>
> Dené–Caucasian is a proposed language family that includes
> widely-separated language groups spoken in the Northern Hemisphere:
> Sino-Tibetan languages, Yeniseian languages, Burushaski and North
> Caucasian languages in Asia; Na-Dené languages in North America; and
> the Vasconic languages from Europe (including Basque).
>
>
>
<https://en.wikipedia.org/wiki/Den%C3%A9%E2%80%93Caucasian_languages>
And once you figured out some of American languages this way (i.e. learned it), you can use said knowledge to help decrypt other American languages, especially language of neighbors of speakers of said American language.
] |
[Question]
[
OK so this world I'm building has Earth-like flora and fauna, along with being around the size of Earth and being around the same distance as Earth from a star the size of the sun. The atmosphere is similar to Earth's as well, and the climate of the land area of the planet is temperate oceanic, similar to that of Britain or Ireland. Would it be possible that in the forests of this planet, trees are joined by tree-sized mushrooms? (When I say tree-sized mushrooms, I'm thinking ones around the size of huge red mushrooms from Minecraft, so not super tall but large enough to provide some fungal lumber)
[Answer]
[They did.](https://en.wikipedia.org/wiki/Prototaxites)
Now, the first trees evolved on Earth right around the same time that Prototaxites went extinct, so perhaps trees just out-compete them and they really can't co-exist... but it's not entirely obvious *why* Prototaxites disappeared when trees showed up. If they were actually lichens, relying on photosynthesis from their algal component to survive, then it makes sense that they would've been competing for light, but otherwise there's not a whole lot for a mushroom and a tree to compete for, and they should be able to co-exist just fine.
So, just make your giant mushrooms actual mushrooms, and not lichens. If they don't photosynthesize, or don't rely on photosynthesis, you will need some other excuse for them to grow tall, but that's easy to manage--maybe they do it for seed dispersal, for example.
[Answer]
My comment as an addition to Logan R. Kearsley was too complex, but see this as an addition to his answer.
It would make it more difficult for a mushroom to grow into a treelike structure than a lichen. They draw energy most often from either living things or the decaying matter. That means it requires a constant source of other living things to grow, while not competing with too many other living things for space.
That being said: meet the Humongous Fungus. <https://www.google.com/amp/s/www.businessinsider.com/largest-living-organism-the-armillaria-ostoyae-fungus-2017-5%3famp>
I just grabbed the first google link, but should tell enough of the basics. It can grow huge and has here and there small mushrooms that break the surface (which incidentally is also how mushroom rings form. Certain kinds of fungi growing underground mostly circularly and grows our well known mushroons at the edges to spread it's seeds).
You can take lessons from it and have some fungi grow large underground, breaking the surface here and there to grow large treelike fungi.
To add to this, fungi can do more than just decay things. They are used everywhere for communication between plants in exchange for nourishment. <http://www.bbc.com/earth/story/20141111-plants-have-a-hidden-internet> (again, first google hit. I didn't really read it but should tell you the general stuff). You can use this for a less destructive form of the fungi.
So with some changes that are unlikely but not unrealistic, yes it might be possible.
] |
[Question]
[
In my current worldbuilding project, humans find themselves struggling to survive on a cold, dead world with minimal sunlight and the aid of magical machines called "spinners". Spinners are two identical cubes adjoined by a face, always counter-rotating w.r.t one another at a constant rate. No amount of ungodly toque can slow their rate of counter-rotation, betraying unlimited, tappable work.
People use these machines for generating heat and powering machines and vehicles. My question is, what is the best way spinners may be incorporated into the design of a rocket engine? (Couple notes: the fastest spinners rotate at around ~1 Hz which, due to their unwillingness to be slowed by counter-torque, can be geared-up to hundreds, thousands, or hundreds of thousands of Hz by a gearbox; the engine need not necessarily have a thrust-to-weight ratio of 1:1 or greater--the focus is maximum delta-v.)
This sort of perpetual motion won't necessarily get you off the ground and into orbit for free. Rockets will still need exhaust to push on to generate thrust in a vacuum. So, spinners neither eliminate the need for fuel nor the tyranny of the rocket equation.
My knowledge of rocketry is weak, but I imagined a spinner-powered thermal device could be used to heat some propellant, say, liquid hydrogen, up to a few thousand Kelvin like in a typical nuclear thermal rocket, except the nuclear energy doing the heating is replaced by this spinner-powered thermal device. The thermal device could work by forcing a great deal of electricity through many tightly-wound metal coils (the spinners would be used to generate the strong rotating electromagnetic field). The friction in the coils would heat the propellant and so on. However, I don't think there is a metal or metal alloy that doesn't start vaporizing above ~2000 K (probably less than that, actually). At that point, one may as well forget about spinners and use nuclear elements instead.
Is what I suggest feasible? If not, is there another way to feasibly incorporate spinners into rocket technology? (I don't want to continue with the development of my world into the *off-world* without knowing the applications of spinners in space.)
[Answer]
# Electrolysis & Fuel Generation Until You're In Orbit
Not only are you correct about the temperatures at which your heating coils would start to fail, the gearbox needed to generate that kind of power would be prohibitive in terms of of the space required on board the vessel. So...
If you've got life, you've got water (or other materials from which hydrogen and oxygen can be extracted). That gets you into orbit - nice traditional cryogenic launches.
Once you're (most of the way) out of the gravity well, however, that's when your spinners can really shine. You've got unlimited energy, so you want to minimize reaction mass; perfect situation for an [ion engine](https://www.researchgate.net/publication/282980210_Mission_Design_Study_of_an_RTG_Powered_Ion_Engine_Equipped_Interstellar_Spacecraft). You could have unlimited burns. It would take a while to get anywhere, but you would have effectively unlimited range.
[Answer]
The machines provide the ability to have a reasonably compact source of enormous electrical power. Let's assume this power is "infinite" for practical purposes. In reality it will be limited, but the limitation is with the material science they can screw onto the ends of that cube. With cube size not specified this is hard to estimate.
So.. Ample electrical power. At the very least, some hundreds of megawatt to gigawatt of power.
**To get to orbit:**
[Electrical propulsion. Ingest atmospheric air, superheat it to plasma.](https://www.newscientist.com/article/mg23431264-500-plasma-jet-engines-that-could-take-you-from-the-ground-to-space/) Eject the plasma through an acceleration grid. Simple, strong and horrendously inefficient. Fortunately, with "infinite" on one side of the scale, efficiency is a mere footnote.
**In space:
If you are in a hurry:** Your fuel is whatever matter you can lay your hands on. Lighter atoms are more useful, hydrogen is ideal. But plain old water will work *fine*.
Same story as in the air, just superheat the stuff to plasma, then violently shove the plasma to the rear using strong magnetic fields. Something like the [VASIMR](https://en.wikipedia.org/wiki/Variable_Specific_Impulse_Magnetoplasma_Rocket) engine. But again, because we have near infinite power available, we can leverage the reaction for thrust and fuel efficiency, rather than being worried about power as mere mortals have to.
**If you are not in a hurry, near a planet with magnetic field, and refuse to spend fuel:**
[Just hang a long tether overboard](https://en.wikipedia.org/wiki/Electrodynamic_tether), run Thor's own electrical current through it, and use the interaction of that magnetic field with the planetary magnetic field to move around in your orbit. Slow, burn silly amounts of power for very little acceleration, but power is free and it uses absolutely zero fuel.
**If you are not in a hurry, and nowhere near a magnetic field, and still refuse to spend fuel:**
Use your electrical power to run a [photon torch drive](https://en.wikipedia.org/wiki/Photon_rocket). This is the point where you realize that your "infinite" electrical power is anything but infinite, and true infinity would have been useful. Still, a couple of gigawatt of power is enough to power a workable photon drive that will take a light starship to relativistic speeds in years, rather than centuries or millennia.
[Answer]
**Forget launch rocketry, use an elevator, then use an ion thruster in space**
If nothing in the universe can stop a spinner from spinning, then use them to power a space elevator. It might take a day or two to complete the transit, but you're guaranteed to do so regardless the weight of the load (ignoring the mechanical specifications and/or limitations of the car & elevator tower).
Once you're in space, you can use [ion thrusters](https://en.wikipedia.org/wiki/Ion_thruster) to move around.
[Answer]
# Space based jackass merry go round to anywhere
Taking one of these things to low Earth orbit should be relatively cheap. From there you can reach to the stars.
Now have a launcher that is a long cylinder, with such a spinner attached to, and powering a [reaction wheel](https://en.wikipedia.org/wiki/Reaction_wheel).
You can make the reaction wheel spin arbitrarily fast, and with it the external surface of your launcher. Now all you need is a decoupler on that surface.
Mount your interstellar vessel on that decoupler. Accelerate the launcher to the necessary angular velocity. Activate the decoupler, and the vessel leaves the launcher on a tangential with the same velocity as the launcher's surface's linear velocity.
---
If you are having trouble visualizing how this contraption would work: the launcher is this merry go round, the reaction wheel is the back wheel of the motorcycle connected to the merry go round's axis, the spinner is the motorcycle's engine and the vessel to be launched is the guy who gets a lesson in cruel physics.
---
Wanna escape the Earth? I remember its escape velocity at LEO is below 11 km/s (the escape velocity at sea level), so using that value will do. Wanna escape the sun? You just need to be going at 42.1 km/s when you exit Earth's sphere of influence. If you wish to reach any specific star or even galaxy, you just need to figure out a trajectory and the proper speed - and the spinner + reaction wheel combo will make sure you can reach the latter in finite time. No delta-v budget is too expensive anymore.
If you wish for an orbital injection at the destination, you can make it so that the main vessel also has a spinner and a reaction wheel, and then you can do this mad maneuver in reverse. You will have all the time of the trip to build up angular speed for this secondary launcher.
---
**Edit:** As per Harabeck's comment:
>
> [SpinLaunch](https://en.wikipedia.org/wiki/SpinLaunch) is a real company trying to do something close to this conceptually.
>
>
>
It was founded in 2014, so the concept for the space based jackass merry go round has been a thing for quite a while now.
Also in space you don't need a perpetual motion machine - sunlight is practically unlimited, and you can keep converting solar energy into reaction wheel love as long as the materials involved can take the stress.
[Answer]
For getting into orbit, you could use the spinners fairly easily to power a [Lofstrom loop](https://en.wikipedia.org/wiki/Launch_loop). The classic issue here is largely "you really want several nuclear reactors to power the thing" (which has political issues among other things), which you sidestep fairly easily. (Why nuclear? Because it requires a fair bit of power, and rather reliable power at that. Both of which you have here.)
(There are ways to deal with a power failure on a Lofstrom loop, mainly involving stealing momentum from the cable itself to keep the containment going, but it's, uh, hair-raising at best.)
(For reference: a Lofstrom Loop (or Launch Loop) is effectively just a really large loop of cable, spinning quickly enough that its own inertia holds it up against gravity. To launch, just steal momentum from the cable.)
---
Once you're in orbit, a couple of possibilities spring to mind.
One obvious approach is an [EDT](https://en.wikipedia.org/wiki/Electrodynamic_tether) (electrodynamic tether). An electrodynamic tether is essentially just using the magnetic field of whatever you're near as the magnet for a generator/motor. Normally these are largely used "in reverse", to provide power at the expense of decaying your orbit, but you can use this as a motor too (taking power to raise your orbit, essentially).
They do have a bunch of downsides (power-hungry, relatively low acceleration, can interfere with nearby craft, etc.), but their main drawback is simply the power use - and you've got power in spades. And they don't use reaction mass.
One more classical approach here is an ion drive. Normally an ion drive has a relatively low *effective* Isp, mainly due to the mass of the engine's power supply - but you have power to burn. So you can run at very high power consumptions (which boosts efficiency). Still a very low power-to-weight ratio however.
A photonic drive sounds great initially. Honestly however, this likely isn't worth it. Even assuming "infinite" power, we don't have any good way to produce anywhere near the photon density required to make it worthwhile.
(As an aside, I'd expect the early space program to focus far more heavily on [magnetohydrodynamic drives](https://news.mit.edu/2018/first-ionic-wind-plane-no-moving-parts-1121) for airplanes than we did. They have largely been discounted for us due to a lack of a decent power supply... but given these you could probably build a fairly decent spaceplane.)
(As another aside: I actually think that it'd be rather difficult to use these. The required torque (and hence, mass) to get a decent amount of power from a 60RPM rotation is not exactly small. 1 horsepower would require ~550 pound-feet of torque (for comparison, a bicycle is, what, 50-100 pound-feet of torque?). Someone who is more patient than I could probably work out the maximum effective amount of power you can get out of one of these based on material limits at the attachment point... but I expect it to be surprisingly small.)
[Answer]
>
> This sort of perpetual motion won't necessarily get you off the ground and into orbit for free.
>
>
>
Actually, it can (maybe), if your engineering is good enough. Leaving aside PcMan's answer...
We know how to produce thrust by pushing air around. Getting to orbit isn't a matter of getting *high* enough (well, unless you want to get really, ***really*** high; so high that, without a reaction-less drive, this approach simply isn't practical thanks to the tyranny of the rocket equation) but of going *fast* enough. So... do this *in the atmosphere* so that you can use the planet's air as reaction mass rather than having to haul your own. If necessary, produce *downward* thrust to keep yourself in the atmosphere until you've got to your desired speed. You might still need to bring along some delta-V for orbital corrections (though, see other answers), but not *nearly* what you would need to just get to orbital velocity.
The trouble comes when you need to balance the required speed against certain unfortunate effects of atmospheric heating, which means you probably need to do this at a sufficient altitude that the air is thin enough for this to be manageable. Thus, you probably are looking at something like a ramjet engine. Also, really, really good heat shielding.
] |
[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/74649/edit).
Closed 6 years ago.
[Improve this question](/posts/74649/edit)
In the future, if medical technology is significantly advanced and humans live indefinitely, or at least for human lifespans have increased by tens or hundreds of years, how will marriage/divorce/monogamy be affected? What are reasons why marriage, divorce, and monogamous relationships would become more common, less common, or about the same as now?
---
Some thoughts:
* The naive view might be that if technology is so advanced, people will indefinitely remain young unless they decline / cannot afford / aren't allowed treatments to keep them young. Having a young active body may encourage more casual relationships and cause people not to be married. However, I would argue that the usually more casual relationships of youth are related to chronological age / life experience, which obviously happen to be highly correlated with biological age, but is not caused as much by having a young body. So, even if people are biologically young, they may still get married because chronologically they've had some amount of life experience and feel like getting married.
* If people live for hundreds of years, they will grow apart, so divorce will be a regular thing that happens after a few tens of years. So people will cycle through many marriages. Or knowing that this will happen, marriages will become much more contractualized and e.g. the marriage must last for X years before divorce is allowed.
* Thinking of dating / marriage in terms of an sort of an optimal stopping problem or exploration/exploitation tradeoff, longer lifespans will allow for a much longer exploration phase, delaying the average chronological age at which people get married.
* Two people who are biologically young could be vastly different chronological ages. The older one would have lived through many more historical events, had more life experiences, have more knowledge, etc. Think of grandpa with his wisdom marrying a 20 year old. In our current world, the main contribution of the 20 year in this marriage would probably be a young body, and also a youthful and energizing attitude. But if they are both people are biologically young, this is less of a relevant. So the chronologically older person may seek someone who is more compatible chronologically as well and has roughly the same amount of wisdom / experience etc. So this could cause stratification based on chronological age as well.
* Depending on rules of wealth transfer between generations, marriage could take on more or less importance as a means of connecting people legally / financially / for immigration purposes, etc.
* On the other hand, maybe marriage will still be very common but it will just increase the average chronological age at which people are married. Although two people may have the bodies of 25 year olds, they may chronologically be 50 years old, have had many explorative casual relationships, and now be very firm in their decision to remain married forever because they feel they've finally foudn someone very special that they will never want to leave.
[Answer]
Coming from a young marriage, a religion that places great emphasis on family life, and [a wonderful TED talk](https://www.ted.com/talks/jenna_mccarthy_what_you_don_t_know_about_marriage/transcript?language=en), I believe that *the evidence for monogamy and marriage may be strengthened with longer life spans.*
* Life-long, monogamous marriages are based off of several principles, including forgiveness, humility, service, and acceptance. Such successful unions will have prime, living examples which can teach those who are struggling or inexperienced.
* Married people (IRL) have more sex than single people! As exciting as a new sexual conquest could be, why risk that when you have a very attractive person, who you know would love to have sex with you, *right there*!? (see TED talk) Throw in that biological immortality and you can have ***years*** of wonderful sex with a partner you have had many (and likely continuing) adventures with.
* Married people tend to live longer, healthier lives. (see TED talk) Even with advanced medical technology, marriage could still have these effects of a "merely" improved life. Even little improvements over a long time makes a big difference!
* There are up to 1,000 legal benefits under current US law. I doubt US law, and the law of most republics and democracies would be nimble enough to get rid of most of these in time. (see TED talk)
* There can be other benefits, such as religious ones, but that is depends on the culture and religions a couple finds themselves in.
* If there are are sexually transmitted diseases in this future, and there are only treatments (not cures) for particular ones, monogamy does provide protection from these. If you need to pay 5 US dollar/month for treatment for the rest of your life, and you have a good 100 years ahead of you... well, that $5 could have been put to another, more lucrative, use.
While I'm sure more thought would yield more, I do think there is a solid case for increasing monogamy coupled with longer life. Of course, this can be countered by societal influences. I still think monogamy (or near monogamy) would win out with longer lifespans.
[Answer]
I think the only major difference you would see is a significant reduction in "biological clock marriages."
Biological clock marriages here being marriages that were timed around biological issues, such as:
* Wanting to find someone before beauty fades
* Wanting to have children while still physically able
* And not wanting to die alone
I suspect some more or less "settle" as these deadlines approach, if the deadlines are significantly delayed or removed, well obviously you wouldn't see that. These issues could also play a role in marriage/divorce rates.
---
On the whole I suspect that people would still just be people, perhaps older and wiser people, but still just people. Most any marriage arrangement or configuration you can imagine has been tried by someone in some culture at some point in human history. Monogamy, polygamy, polyandry, arranged, young men to old women, young women to old men, same-sex, gender neutral, and even chaste, non-sexual, and asexual. Some people have even married their deity/ies. Forgive me I know I've left some out, but you get the picture.
Trust me if you can imagine it, it's probably been done. With all these variations and possible combinations it usually boils down to "the heart wants what it wants." Even in arranged marriages people make it work for the love of their family, traditions, religion and so on.
**So... People will likely do what they would have done anyway.**
[Answer]
In the heartbreakingly beautiful SF Novel *The Sparrow*, a younger woman asks an older how she has managed to stay married for 40 years. She answers that she hasn't: she and her husband were married 4 times for 10 years at a time: every 10 years, she and her husband would come together, take thorough stock of themselves, and then decide whether to continue or not. I suspect any solution to the question you pose will ultimately have to come from the human heart, and this one strikes me as a good one.
[Answer]
By current trends:
More diverse. More personal.
Traditionally marriage was a matter of the community, a pact between two families, which transformed to marriage being a religious institution when local community and local congregation were largely synonymous. With people mostly no longer living in single religion communities and marriages between religions being more acceptable, marriage is returning to being secular arrangement between people. Since such arrangements are more personal and not required to match specific religious dogma, the arrangements will become more diverse and matched to the needs of the people involved.
There is no particular reason why "gay marriage" or polyamoria would be particularly controversial in the future, for example. The controversial aspect is that they do not match the traditional model of religious marriage, once the institution of marriage adjusts to the reality of freedom of religion, the controversy will disappear.
A possible side effect of marriages becoming more personal is that they might become more of a private affair. The large festivities associated with marriage are from their nature as shared matter for the community, congregation, village, extended family. None of these might be particularly relevant with more personal marriages, so there might be very few people involved without any special celebration.
By your scenario:
Marriage contracts might be time limited with options for renewal.
Why have divorces when it is much more practical to just accept that people might grow apart in the future? Oddly enough this would not necessarily reduce the commitment people have for their marriages. Reality bites whether you formally acknowledge it within your institutions or not.
Having agreed upon time limits would reduce divorces as people would simply wait for the marriage to end naturally. It might even increase commitment as people might be expected to make effort to "work it out" until the term runs out. It is much more reasonable and realistic to expect people to put effort to their marriage for a few years more than for the rest of their lives.
[Answer]
Monogamy is changing already - the various forms of non-monogamy such as polyamory and open relationships are appearing more often in our society as people realise that they have choices, and that having affairs and lying are far more damaging than being honest from the start.
Saying that - I feel that the legal aspects of marriage will stay stronger than just cohabiting. If people get a true benefit from marriage then it will be used for taxes / security / etc.
To counter that I think that marriages will become more like a legal contract. There will be fixed term marriages where they can be extended at will, or where they can be let go without any acrimony. Maybe there's an extending marriage. You get married for one year, then five years, then can choose to make it permanent if you both wish (or just continue extending it every decade - after all, it's a good excuse for a party!)
The strongest part of a marriage (or any relationship) tends to be communication. With improvements to technology then hopefully communication itself would be easier. No need to bury your head in the newspaper when you can enter VR and play the latest games together - you'd pretty quickly learn what sort of person your partner is by their behaviour if their choices had no (physical) consequences in real life - which would hopefully lead to stronger relationships and marriages (and conversely more long-distance relationships).
As mentioned elsewhere the overriding reason for marriage is a legal one. Who do you love enough to give the legal power to switch off your life support to (worst case, but valid). If you have a life expectancy of centuries then that question is far more valid and pertinent.
Age differences will be even less of an issue than now. Sure - people will talk and look (and sometimes make assumptions on the relationship), but if people don't continue to age visibly then those assumptions start going, and it becomes a number that's pretty much irrelevant when weighed against maturity and compatibility.
Marriage itself would need to evolve, to match the two types of people that want it: those who throw themselves into everything completely, but will also change over time and want to move on. And those who carefully consider and want something to last for those centuries.
Over time I think the only thing that will change marriage is law - how people feel, interact, and behave, will pretty much always be the same, just their choices available that change.
] |
[Question]
[
**Closed.** This question is [off-topic](/help/closed-questions). It is not currently accepting answers.
---
Questions about Idea Generation are off-topic because they tend to result in list answers with no objective means to compare the quality of one answer with the others. For more information, see [What's wrong with idea-generation questions?](//worldbuilding.meta.stackexchange.com/questions/522).
Closed 7 years ago.
[Improve this question](/posts/37018/edit)
A sense is something that provides an organism with information about its surroundings. Humans have the five senses, sight, hearing, smell, taste, and touch (sensing pressure). However, some creatures also have electrolocation, where they are able to detect electrical fields.
I'm trying to come up with different senses to give my alien races to make them seem more, well, alien.
What other senses are there, if any, that I have not already named? Are there any other ones possible?
Note - Echolocation I am considering as simply very good hearing. Also, I don't want answer about some kind of "sixth sense" like knowing someone is watching you, or telepathy, or anything like that.
Edit - I am looking for external senses, that tell about your environment, as opposed to senses that tell you about your own body, like thirst or the sense that tells you were your body parts are.
Edit 2 - I'll concede that sonar is different from hearing, since it gives you a kind of image of what you're screaming at instead of just listen ending to tell the location of things.
[Answer]
I think we can go two ways with the question.
**Perceived Senses**
The first way is to assume "sense" refers to a set of inputs that we perceive and process as some type of information. So vision would be considered a single sense, smell a different sense, etc. In this case, humans have sight, touch, taste, smell, hearing and balance as base senses, along with the possibility of electric and magnetic senses most of us don't pay attention to (if they exist at all). And all the subdivisions of those senses, such as touch giving us sensations of temperature, texture, pain, pressure, [stroking](http://news.bbc.co.uk/2/hi/science/nature/7610383.stm), etc.
This way, the question becomes too broad, as there's really no limit to things. An alien could sense magnetic fields in a way comparable to our sense of vision, while EM radiation could just be felt as some kind of environmental pressure. This alien might see a server room, with all it's tiny little magnetic fields forming and dissipating at high frequency, as a disco dance floor, while only being mildly aware of the difference between a brightly-lit field and a dark cave.
**Underlying Physics**
Another way is to look at what we're actually perceiving, regardless of how we perceive it. So sight is some method of perceiving EM radiation, touch is a method of perceiving direct pressure, sound is a method of perceiving mechanical pressure waves, etc.
In this case, the question is still going to be broad, as there are a lot of grey areas. Sound is ultimately just a form of touch, for example. But we could list a few basic things to detect:
* EM radiation.
* Direct pressure.
* Vibration.
* Acceleration.
* Chemical interactions.
* Electric fields.
* Magnetic fields.
* Temperature.
* Radiation. (Shamelessly stolen from [Bryan McClure's answer](https://worldbuilding.stackexchange.com/a/37027/11879).)
Of course, these things could be perceived in any number of ways, affected by the spatial, frequency, and amplitude resolutions of the sense in question. An alien who has multiple vibration sensors touching the ground could sense the phase difference between the incoming vibrations to determine the direction and distance of the vibration's origin, for example. With enough sophistication, it could make a 2D map of the ground in a wide radius by inferring reflections, frequency shifts, etc.
And the senses aren't stand-alone. Our sense of spatial awareness pulls information from both sight and sound on a regular basis, while having negligible input from our sense of taste. An alien could potentially smell the "color" of a tree as being distinct from that of a rock, and combine it with some type of echolocation to paint a picture of its environment more detailed than either sense alone could give.
And I think this is how you would make an alien seem alien. It's not that an alien is going to see using some mystical magic field we've never heard of, but that the alien senses its environment using the same senses we have, in ways we wouldn't normally think about.
On Earth, all the magnetic sensors we know of use our planet's magnetic field as a means of north/south orientation. If the alien lives on a world with rapidly changing magnetic fields, it could use the fields to track prey, determine the time of day, communicate with friends, intimidate foes, decide a cold front is coming in, etc. And the possibility of a world with a globally-aligned magnetic field used for direction sensing could elicit a response of "Whoa dude, what kind of alien world would that be?"; "I know, right? We should lay off these mind-altering light patterns."
**Mystical Magic Fields**
Of course, if you want to introduce magical effects, there's no real problem. It's your story, after all. Just try to keep them consistent. And a good way to do that is to start with human senses, and figure out how they work.
You want a magic field that tells your aliens when other aliens are angry? Well, make it so certain chemicals that cause the "anger" emotion release magic "photons" of certain frequencies. Of course, it's probably more complex than that, since there's unlikely to be one, single catalyst for anger. Instead, the aliens would see (feel/smell/whatever) a combination of magic photons of different intensities and wavelengths. Just like "sky blue" is a fairly even mix of green and blue with about half as much red but humans just see a color, "anger" could be some particular mix of adrenaline, various endorphins, and so forth.
[Answer]
Humans actually have 9 senses, not 5. The first 5 are the traditionally recognised senses:
1. Sight
2. Hearing
3. Smell
4. Touch & pressure
5. Taste
6. Heat
7. Balance, acceleration & gravity
8. Kinesthetic (the sense of where our arms, legs and various body parts are)
9. Pain
In animals and plants here are the other recognised senses:
10. Electricity
11. Magnetic field
I honestly can't think of any other senses that may exist. However, some of the senses above may be refined further to extraordinary levels:
* Sense radio waves (sight?)
* See into the extreme ultraviolet and infrared (sight)
* Sense presence like a sixth sense (touch or sound - it could develop from either since both are pressure senses)
* Sense heartbeat/life like a vampire/zombie (electricity - dolphins and some sharks actually have this)
* Sense tremors/earthquakes (touch)
* Sense health/disease (smell)
* Hear infrasound (hearing)
* "See" in the dark (sight/infrared or hearing/echolocation)
* See through walls (sight/xray)
* Sense mass/gravity sensitive enough to feel objects around you (acceleration)
* Smell water
* Taste poisons (we've partially evolved this - it's why we hate bitter foods: most natural poisons are bitter)
* See polarized light (sight)
Radio waves is a bit odd. While a radio antenna might be technically labeled a photoreceptor we don't normally think of them that way. So one might imagine a completely different sense for radio waves. Imagine an animal with a built-in passive radar.
[Answer]
# TL;DR
**Everything that can be measured can also be a sense.**
## Short explanation
* Take a data source of your choosing.
* Feed the data to a neural network (brain).
* Let the network make sense from the data it receives.
* You have created a new sense.
## Long explanation
Neural networks are incredibly well suited for taking in complex (historical) data and allowing you to make statements about a new data point based on previous observations.
This holds true both for *artificial* neural networks used in machine learning as well as for the neural network in humans we call brain.
If you are interested in learning more about potential new senses in humans – or generally senses an organism could have –
you should check out David Eagleman's 2015 TED talk ["Can we create new senses for humans?"](https://www.ted.com/talks/david_eagleman_can_we_create_new_senses_for_humans?language=en).
He shows how you can use technology for what he calls *sensory substitution* – e.g. giving deaf people a sense of hearing –
and *sensory addition* – i.e. tapping into data humans cannot naturally perceive and creating artificial senses.
He developed a *vest fitted with several vibrating motors* on it's back.
Using a microphone to get auditory data which was translated into a *complex pattern* of vibrations of the different motors – too complex to consciously grasp. He **enabled a deaf person to recognize** how certain patterns correspond to **certain words** spoken. This was achieved after just a **few days of training**.
He also managed to "extend" the senses of pilots to a remote-controlled quadcopter by streaming flight data to the vest.
Two more applications mentioned in his talk:
* Stock market data from the internet
* real-time results of text analysis of twitter feeds (positive/negative) during his talk
This all just goes to show you **there is basically unlimited potential for creating senses**.
Some more ideas for senses and applications:
* sensing density of materials – side note: [human echolocation](https://en.wikipedia.org/wiki/Human_echolocation) already allows you to do this.
* sensing structural integrity, e.g. know when a building is about to collapse
* sensing chemical composition – think [spectroscopy](https://en.wikipedia.org/wiki/Spectroscopy) or super taste
* sensing objective rareness – although humans can recognize something subjectively as being rare
from their personal experience, if you get fed data measured globally you could sense things as being rare independently of you having encountered it individually.
Note: The description of the "rareness sense" is intentionally vague to convey how abstract and intangible a sense could be.
However, if the fictional organisms you are designing should have a naturally occurring form of sensory perception, you have to think of a plausible low level
mechanism that generates the data, i.e. some receptor is excited in some way due to some phenomenon.
[Answer]
Ability to "see" heat. We have machines that can do that, and certain animals have similar abilities.
Depending on what environment your aliens come from you could have creatures that can sense the presence of radiation. This could be particularly useful for creature living in a very radioactive planet. Maybe through some form of sight or smell. This ability would call them to sense radiation from far away and avoided it.
Read a book once where an alien had the ability to sense "Mass" the details weren't exactly explain though.
[Answer]
Several have said that humans have more than five senses, but based on your statement that you consider echolocation just very good hearing, you could say that really we have only 3 senses: electromagnetic radiation (sight, temperature), chemical reaction (taste and smell, acidity), and kinetic energy (touch, hearing).
One could imagine extending any of those, such as:
Sensing radio waves or other parts of the EM spectrum.
Sensing heat in a way that allows you to "see" a picture of the heat sources around you, like night-vision goggles.
Perceiving other sorts of chemicals, like being able to "see" or "smell" chemicals produced by other living creatures, and so literally "smell fear", etc. Or being able to look at the ground and see where there are metal ores or oil.
Feeling other forms of motion or vibration, like sensing subtle air movements, e.g. know what weather is coming, subtle ground movements, e.g. know an earthquake is coming. Or know when things are moving near you by changes in air pressure.
Directly sense magnetism.
What senses could one have that go in a totally different direction?
Someone mentioned sensing gravity. (Whether there is such a thing as gravity waves or not, one could still discuss sensing a gravitational field.) This could tell you your altitude if fine enough, which might be useful. Not sure what else it would do for a creature living on a planet. If the creature can travel in space, either naturally or in a spaceship, this becomes more useful.
Directly sense nuclear strong and weak forces? I'm not sure how that would work or be useful to a macroscopic creature.
You mentioned you're not looking for telepathy and such. That reminds me of a story I read years ago by Murray Leinster, I forget the title, where humans meet aliens, and they learn that the aliens communicate by broadcasting microwave signals between their brains. And one person says, "They have telepathy?" And another replies, "Sort of. But from their point of view, we have telepathy, because they've never thought of sound as a means of communicating." Which I thought was an excellent point. To aliens who do not have ears, the idea of communicating by generating and receiving sound waves might seem like a mysterious psychic phenomenon.
[Answer]
Beyond the basics:
* Extending visual into ultraviolet/infrared
* EM fields, sense hidden creatures/active electrical devices.
* Magnetic fields, never get lost.
You could have more complex options:
* Ability to distinguish between acceleration and gravity: I can't see a use for this, but why not given that the theory of gravity says it's impossible.
* Sense tensions in structures and materials: Allows you to see where something will break, or even predict earthquakes.
You could even give them different ways of interacting with the same information. Seeing infrared is an easily understood example, we can *feel* heat, but if you can see into infrared then you can "see" heat. As my father used to say:
>
> Don't talk to me in that tone of voice, it smells a funny colour.
>
>
>
[Answer]
There are some things I could imagine:
* See Radiation
* Night vision or similar
or my favourite:
**See in four dimensions!** It is **very** unlikely that this would be possible, but we once thought the earth was a plate :)
No human could ever get or imagine how this would work or even worse how it would look from their point of view. But this would really make them to some super aliens, so if you're going the let your protagonists fight those aliens you'd better chose one of the other additional senses :)
PS: English isn't my native language (as you can easily tell) so feel free to correct my typography/grammar
[Answer]
Perhaps there is an alien race that has an extremely sensitive organ that can sense gravity waves. Consider that we have recently detected them with LIGO:
<https://www.ligo.caltech.edu/news/ligo20160211>
Gravity waves are an entirely new way for astronomers to "see" things in space. So maybe these alien can sense gravity waves the same way we feel the wind on our skin? And perhaps the more fierce the gravitational event, the greater the sensation?
For example, the gravity waves we detected from LIGO were from the most intense moment of when the two black holes were colliding, called "ring down." Consider that to detect this "crest" of the waves coming out of this event, we needed an event as violent as two black holes colliding, each of which are many, many solar masses swinging around each other at 1,000 revolutions a second before they collided. The rest of the waves from the event were too weak to be detected by LIGO. So these aliens' senses would have to be attuned in such a way that the noise from all the gravitational perturbations in spacetime wouldn't overwhelm them.
[Answer]
What about a chemistry sense? This would work in a manner similar to taste and smell, but to a far more accurate degree, so it could tell you the proportions of different elements and chemical structures in your surroundings. Basically a creature that evolved to understand and use elementary chemistry on an instinctive level, and would know immediately upon sniffing two different chemicals what would happen if you combined them, even if it had never encountered them before. Since chemistry is basically applied mathematics, it is not impossible for an organism to have such an ability, and would certainly lead to a very alien way of seeing the world. Bonus points if there are non-sapient organisms on the planet that have this ability as well - you don't need to be sapient to 'understand' the rules of Newtonian physics.
[Answer]
Like others have pointed out, humans have more than five senses. But this knowledge isn't really useful for making an alien species with new senses. Instead, take a look at some other animals. Some animals have senses humans don't have, and others have the same senses that humans have, only more sensitive and with lateral application that would make you think a comic book author came up with them. Echolocation is a great example. Another good example is [roaches having Spider-Man's "spider sense"](http://articles.philly.com/2000-06-15/news/25602235_1_hanan-davidowitz-wind-speed-and-direction-roach).
Another good idea is to look at the problem the other way around. Think about the environment and what information about it we can't directly observe. For example, imagine if we could sense germs. Well, that would suck on Earth but maybe not wherever your species is from.
[Answer]
this has been said before, but after a certain point you start to run out of different ways to input data about an organism surroundings in ways that are meaningfully different. maybe try to change what the aliens do with the information that they receive? you could have a race that only processes data on a subconscious level, and literally cant recognize the physical world. maybe the aliens think at a wildly different timescale than humans. or maybe they perceive the world in some even weirder way, something so far removed from our human thought processes that they can barely be said to live in the same universe? who knows! (apparently not me)
[Answer]
I'm surprised nobody has mentioned sensing the passage of time, although that's hardly alien. One odd manifestation here on earth are the various N-year cicada broods. If they do not count (which seems unlikely) they have either a number sense or a remarkably accurate longterm clock!
The other thing is that a cetacean's sonar sense is almost certainly very much more than "enhanced hearing". It is a form of seeing, but very different in what can be perceived. At its simplest, most objects (food, people) are opaque to visible light. Ultrasound goes through them, reflecting in complex ways at boundaries. Interpretation will give a 3D map similar to a CT scan.
So a dolphin can almost certainly see other dolphins' internals. Stomach and bowel contents. Pregnancy. Tumours. Heartrate and muscle tension. Also very probably their own internals. I wonder whether it is possible for a dolphin to lie? On top of that it may be possible to directly create sound signals having properties something like a low resolution hologram in another dolphins sonar view. This might be as close to telepathy as is physically possible. Far beyond speech as we know it.
I say dolphin but we still do not know how smart our dolphins are. Too alien to understand? Or not quite as smart as we think or hope? If alien "cetaceans" have achieved technology despite the handicap imposed by an aqueous environment it is a fair bet they are considerably smarter than we are.
] |
[Question]
[
Ornithopters are vehicles that fly by flapping their wings, rather than trough use of a propeller or jet engine. They've been proposed and built many times throughout history, and are a common element of science fiction and fantasy.
*Leonardo DaVinci's design for an ornithopter*
There's at least one good reason why ornithopters have captivated so many: they are incredibly cool. However, while bio-mimicry can be useful for micro UAVs that are attempting to disguise themselves as birds, I'm not sure what advantages they would have over conventional aircraft. Is there any compelling reason, aside from a cool factor, why a civilization would develop and use ornithopters over fixed-wing aircraft?
[Answer]
You are so right about the cool factor. :-)
I can think of one reason. OK, two.
First, if you posit a technology whose main mechanical motion is biological, or at least has a gross design not unlike animal muscle/bone arrangements, the reason for using an ornithopter is straightforward: same as birds. Propellers and fixed wings work beautifully for systems engineered with bearings for rotary motion; but when fuel is converted to motion via a flex action, wings make a lot more sense.
Second, and somewhat more subtle: the shaft/bearings/propeller anatomy favors high-speed rotational inputs, while stretching/shrinking muscles are much more efficient at lower speeds of motion. The speed of the original motion generated is roughly proportional to the *intensity* of the energy source.
My muscles do not burn as hot as gasoline, but I can ride my bike further on a given quantity of food calories than an equivalent amount of gasoline calories, fed into a little bolt-on internal-combustion engine, could take it...
So anyway, if you have low-intensity energy inputs, your technology would probably want to fly an ornithopter.
[Answer]
**Stealth**
Flapping does make noise, but significantly less than a propeller or jet. If it's important to you for any reason that you make less noise, you might go with a flapping-wing solution. That could be anything from a species with incredibly sensitive hearing, to large airborne predators that are attracted to sound, or being sneaky during warfare.
**Maneuverability**
I'm not sure there's any real-world data for this, but presumably a flapping-wing aircraft would be able to go at significantly lower speeds than a fixed-wing craft without stalling. That would give it a smaller turn radius when it needs it, and the ability to land or take off from smaller runways.
Any coptor design though will beat a flapping-wing design for this though, so it's not sufficient by itself to justify a flapping-wing craft.
**So where do you use them...?**
The most obvious answer to me, based on the above two criteria, would be if you needed to fly in something like mega-jungles (huge trees with wide separations and a canopy overhead). A fixed-wing craft needs decent runways - a flapping wing craft could possibly take off by being pushed off the right tree. And the need for a low speed to avoid hitting things favors flapping-wing as well.
[Answer]
Flapping wing designs are what came first in our history but they didn't work because too high gravity and too thin atmosphere for the weight of the craft.
So in a world with thicker atmosphere and/or lighter gravity and perhaps lighter materials to build them out of, an ornithopter will work and be used until people discover the efficiency of the fixed wing+propeller.
[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.
Hazardous environments where bearing seals would not last well enough to allow for practical propellers or jets.
[Answer]
Flapping as the first attempt at mechanical flight makes sense, since that's what people see birds do. If we're talking a society such as Victorian England, if someone had managed to get a flapping flying machine off the ground, that may have been the focus of inventers for a few decades... at least until the principles behind fixed wing lift were fully understood.
[Answer]
An orni-like technology could make sense for a kind of vehicle which is more a ground vehicle than an aircraft.
I'm thinking about a grasshopper.
You could have a vehicle capable of making great jumps. Then, once airborne, you could use your flapping wings for three purposes : to make your leap longer, to adjust the landing point with extreme precision and to have a soft landing.
Such a thing could be very useful to move fast in an all mountain and jungle uncivilized environment: with one single jump you can go from a mountain top to another, avoiding days of walking in a dangerous valley.
] |
[Question]
[
We lived through loads of questions regarding aquatic races, so buckle up, I am going to gather some ideas around [insectoids](https://worldbuilding.stackexchange.com/questions/4457/what-could-make-intelligent-insect-race).
*The homeworld and race*
* This race lives on a planet which has lower gravity than Earth (0.8 g)
* The planet is hostile in environment, so an exoskeleton is the best evolutionary advantage
* Oxygen level is on oxygen level of Paleozoic Era
* So the race living here either evolved from insect, or at least looks like insect
* The race definitely lives in a hive and is hive-minded
* And I want them to "shoot for the Moon"
*The question*
When I set the definition of their home world and their mindset, I have to explain "why would they want to shoot for the Moon?"
If their home world was a stand alone planet with a moon, I could be hoping for a [Phobos](http://en.wikipedia.org/wiki/Phobos_%28moon%29)-sized moon, which makes no sense whatsoever to go there.
So, the different idea is: The moon is a different moon of the same planet, and *we are already on a moon*.
**But is it plausible?**
Is it plausible to have a gas giant in the habitable zone of a Sun-sized star? Would there be any drawbacks for life to start on one of the moons of such a planet?
**Edit: To clarify:**
I am thinking of a setup, where the main planet is a gas giant the size of Jupiter or bigger. And the *homeworld* planet is orbiting around it as one of its moons.
[Answer]
We have already found exo-planets matching this criteria. For example [HD\_100777\_b](http://exoplanets.org/detail/HD_100777_b) has a mass just slightly higher than Jupiter and orbits its star at the same distance from the sun that our earth does. (The star is a similar size to our sun but I didn't check the brightness so I don't know for sure if it's in the habitable zone).
You can explore the known exo-planets using:
<http://exoplanets.org/plots>
This makes it clear that there are a lot of planets matching the size and distance you need.
[Answer]
**Absolutely.**
This would only take a few simply steps, and a small bit of luck. Here's how it could happen:
1. **A [protostar](http://en.wikipedia.org/wiki/Protostar) forms from a collapsing gas cloud.** A giant sphere of gas and dust collapses upon itself. The pressure is so great that the sphere begins nuclear fusion, and it beings to emit light.
2. **An [accretion disk](http://en.wikipedia.org/wiki/Accretion_disc) forms.** The protostar begins to collect matter around it. Heavy elements formed form supernovae, along with gas, dust, and surrounding hydrogen and helium begin to coalesce into a disk around the star.
3. **Bodies begin to form in the disk.** The disk is really a [protoplanetary disk](http://en.wikipedia.org/wiki/Protoplanetary_disk) by now. Small dust grains begin to grow larger through collisions. They eventually become [planetesimals](http://en.wikipedia.org/wiki/Planetesimal), which group together into large spheres. By now, the star has entered the main sequence.
4. **A gas giant forms.** One of the larger spheres gathers an envelope of gas around it. It accretes material in a similar way to the star, although it isn't nearly as massive as the star. It is now a gas planet. It may collect moons, or form a ring system. Other planets might form around it.
5. **The gas giant [migrates](http://en.wikipedia.org/wiki/Planetary_migration).** Chances are, the gas giant won't form in the habitable zone. However, through interactions with other bodies (such as other gas giants), it may change its orbit, moving further out or closer in to the star. The [Nice model](http://en.wikipedia.org/wiki/Nice_model) says that this happened in *our* Solar System, moving Jupiter and Saturn closer in while Uranus and Neptune moved further out.
Migration is also possible via tidal interactions between the disk and the planet. This may account for why Hot Jupiters are extremely close to their parent stars.
And you're good!
---
**Drawbacks:**
* [Tidal forces](http://en.wikipedia.org/wiki/Tidal_force) on the moon from the planet it's orbiting could be a problem. This is the case on [Io](http://en.wikipedia.org/wiki/Io_(moon)), a moon of Jupiter. Too much stress could have some dramatic effects.
* Possible orbital instabilities could result from the planet's formation. Chances are, the moon didn't form around the gas giant if the moon is so massive. This means that I'd bet that the moon was captured by the gas giant's gravity. This happens occasionally on a [small scale](http://en.wikipedia.org/wiki/Asteroid_capture), but it's plausible here. What does this have to do with the orbit? Well, I'd assume that the planet didn't scoot in to a very circular orbit. It would most likely have a high [eccentricity](http://en.wikipedia.org/wiki/Orbital_eccentricity) initially, although it could become more circular as time goes on, and it might be fine by the time life pops up.
* During the time that the orbit is very eccentric, there's a small - very small - chance that the moon will go near Jupiter's [Roche limit](http://en.wikipedia.org/wiki/Roche_limit) - the sphere inside which a small body may be torn to bits. This would be the death knoll for life on the planet forming in the future.
---
**Could life form here?**
This is tricky. Given the choice, I'd pick a terrestrial planet orbiting by itself over a moon like this to harbor life. In the scenario I just described, there are a lot of factors that could make things tough for life, the eccentricity of the orbit being one of them. I'd say that life here *could* develop, but probably in a more shielded environment. Underground would be my choice. [Extremophiles](http://en.wikipedia.org/wiki/Extremophile) could be the first to spring up, and over time, perhaps they could evolve into the insectoids you want.
[Answer]
How attached are you to the 0.8g figure for homeworld surface gravity?
Smaller moons are generally more plausible; Ganymede (Jupiter's biggest) is about 0.15g. Depending on your assumptions for density, your homeworld would be about 30 Ganymede masses, which is something like 10 times the mass of all Jupiter's moons together.
A larger primary could possibly support that, though. [Here's a paper](http://arxiv.org/pdf/1410.5802v1.pdf) describing simulations of gas giants up to 12 Jupiter masses forming moons larger than Mars.
[Answer]
A very recient SETI weekly seminar (posted on youtube) was about planet formation and migration. [Link](http://www.seti.org/weeky-lecture/viewing-solar-system-orbital-architecture-through-extrasolar-lens)
It is well worth watching to see how gas giants form and move around the system and why ours is the strange one.
From those details, figure how a gas giant moves in and then out, stopping at the right distance; meanwhile it *captures* a sizable terrestrial planet rather than scattering it or rolling right over it.
Basically, add a second smaller giant (like ours), adjust the composition of the protosolar disk and fiddle with the timing by clearing the remaining material at the right time, and add in a dash of luck. Perhaps one of the original close-in rocky worlds is tossed into a long commet-like orbit and it comes back near the same place in a few million years as orbits do, and by then the construction has wound down and it gets captued in a retrograde orbit by the giant occupying its former slot.
] |
[Question]
[
In a setting with Alcubierre-drive starships (as per [my answer here](https://worldbuilding.stackexchange.com/a/367/75)), it is inevitable that once the technology becomes common enough and enough different polities and organizations have such ships, that conflicts will arise that may have no mutually satisfactory outcome, such that people will consider combat with such ships to be an acceptable risk.
However, how could combat occur between two or more Alcubierre-drive ships? How could a planet/star system defend itself against attackers with Alcubierre-drive ships? How could an Alcubierre-drive ship attack a body in normal-space? How could an Alcubierre-drive ship in flight even be detected?
In short, is combat or warfare involving Alcubierre-drive starships possible, and if so, how?
[Answer]
## Create an interference pattern in the space time wavefront.
If I've understood correctly, an Alcubierre drive works by creating a negative wavefront in spacetime in front of the ship and a positive one behind. This moves spacetime around an insulated bubble of space, within which the ship can ride.
Because spacetime moves around the ship it's not possible to hit the ship directly. Any bomb or bullet will simply be warped around the back.
Perturbing the wavefront should differentially affect the speed at which spacetime flows around the bubble, distorting it's shape.
Distorting the leading wavefront in the middle might split the bubble in two. Creating an interference pattern should fragment the bubble and it's contents into many rapidly decelerating parts.
## An Alcubierre drive missile.
The weapon would generate its own space time wavefront or series of wavefronts which, upon striking the gradient generated by the warping ship, would interfere with said gradient, just as a two ocean waves cancel or build upon each other.
A single strike might distort the bubble. Two simultaneous strikes might create chaotic interference patterns. This would fragment the spacetime bubble as the flow was redirected into the bubble, causing different regions of the bubble to move at different speeds.
It would be an elegant but messy way to die. The spacetime in which you stand literally torn to pieces.
It would also have the advantage of being fast enough to strike a ship in flight, provided you could solve the targeting issues, perhaps by firing along the direction of travel.
## A weaponised Alcubierre drive
Of course such a weapon would be extremely dangerous. Because nothing can approach the drive itself you could fire it right through a planet for example.
[Answer]
Anything is possible. This post assumes an Earth-like technology with basically just space-enabled technology. So space-missiles, space-ships, space-mines, etc.
---
Possible the most effective way to attack an Alcubierre drive ship is to attack it's end point. The [Wikipedia](http://en.wikipedia.org/wiki/Alcubierre_drive) article taking about the Alcubierre drive talks about how to travel at very fast speeds using it, you need to begin the process of that travel as many years before as the destination is lightyears away.
>
> Allen Everett and Thomas Roman comment that Krasnikov's finding
> "does not mean that Alcubierre bubbles, if it were possible to create
> them, could not be used as a means of superluminal travel. It only
> means that the actions required to change the metric and create the
> bubble must be taken beforehand by some observer whose forward light
> cone contains the entire trajectory of the bubble." For example, if
> one wanted to travel to Deneb (2,600 light years away) and arrive less
> than 2,600 years in the future according to external clocks, it would
> be required that someone had already begun work on warping the space
> from Earth to Deneb at least 2,600 years ago, in which case "A
> spaceship appropriately located with respect to the bubble trajectory
> could then choose to enter the bubble, rather like a passenger
> catching a passing trolley car, and thus make the superluminal
> journey."
>
>
>
So if one knew where the ship would end up, one could set-up an attack on the destination.
One could also send a projectile into "the bubble." The missile will then either hit the ship during travel or immediately after it arrives. This would not prevent a ship from arriving, necessarily, but it would likely prevent it from doing anything.
---
This rest of this post assumes that the "bubble" of space-time created by the Alcubierre-drive does not push all space away from it, so that only the space "native" (i.e. in the bubble when it was created) ever actually enters the bubble. If this is the case, sabotage would be required to attack an Alcubierre-drive ship in-flight.
The most effective way to attack/defend a moving Alcubierre-drive ship would be a mine that attached to the ship. An Alcubierre-drive still requires the ship to pass over all the space it travels through, it just does so at a very fast rate.
Another way is to send a projectile into path of "the bubble" (see quote above) that the ship will be traveling through. It would have to travel along the same route of the ship, but in the opposite direction, because estimation of an Alcubierre ship's position would be difficult to impossible.
Wikipedia says that the above to methods could work, because
>
> A paper by José Natário published in 2002 argues that crew members
> could not control, steer or stop the ship because the ship could not
> send signals to the front of the bubble.
>
>
>
So even if they knew the mine was in their path while in the bubble, they could do nothing to prevent the inevitable explosion. This might result in the sending out of "dummy ships" to blow up mines and missiles before the main, expensive ship comes.
[Answer]
Ignoring the fact mentioned by DonyorM that the travel must be prepared well in advance, and supposing that ADSS (Alcubierre Drive SpaceShips) behave more in the style of Star Trek where the Captain is able to order changes when in FTL, or enter or leave FTL at will, combat involving ADSS would be a bit weird.
On one hand, it is almost impossible that two ADSS would ever get a combat between them. They are faster than any signal, so it is impossible to detect them from the front. You can only see them from behind or by side, and in these cases they are so fast that would be a waste just to try to follow them to engage, even having an ADSS on your own. Just a fraction of a second while you think after a sudden maneuver of the other ship, and they are millions of kilometers away from where you though they are.
On the other hand, they are very useful as weapons against slower than light targets like starbases and planets. They arrive almost undetected in order to bomb, deploy troops, or whatever other action you can imagine for airborne troops/parachute troops or the air force.
[Answer]
**tl;dr: Disable their drive**
Something that wasn't mentioned in other answers is the possibility of limiting the use or disabling the drive.
For example, in Star Wars the [Interdictor Class Star Destroyer](http://starwars.wikia.com/wiki/Interdictor-class_Star_Destroyer) has gravity generators to stop jumps to hyperspace.
Considering that an alcubierre drive inherently requires warping space time, and gravity is the essentially the slope of space time, if the drive is possible, gravity generators are possible as well. Otherwise, something along the lines of [Ion](http://starwars.wikia.com/wiki/Ion_cannon) or [EMP](http://en.wikipedia.org/wiki/Electromagnetic_pulse) weapons could feasibly disable the drive. I would also expect a device as complex as an Alcubierre drive could be put out of commission by simply ramming the other vessel and knocking something out of alignment, either with the drive or the geometry of the ship.
Combat *at* warp with an Alcubierre Drive wouldn't involve dogfighting and bombardment.
I would presume that the warp speed depends on some kind of power to weight ratio similar to how the top speed of a plane depends on the power to weight ratio. The Star trek universe implies that [more power means a higher maximum warp.](http://en.memory-alpha.org/wiki/Maximum_warp) Easy solution: a missile simply has a relatively bigger warp drive. And to borrow from Star Trek, the warp core of the missile can double as the [payload](http://en.memory-alpha.org/wiki/Warp_core_breach).
>
> ... when the USS Equinox powered its warp drive with energy derived from the corpses of nucleogenic lifeforms, an increase of 0.03% was added to the warp factor ...
>
>
>
It would be difficult (by current standards) to aim of course, but the warping ship would be moving in a straight, and therefore predictable, line. If a missile can go faster than the ship it can intercept it. An Alcubierre-drive ship could feasibly shoot at a ship in normal space as well, it would just require extremely tight timing.
One issue with warp drives is they often can't be used in [close proximity](http://memory-beta.wikia.com/wiki/Slingshot_effect) to a gravity well. I'd expect the ships to have a minimum safe distance. A planetary defense system would defend against warp capable ships as it would against any other. Missiles at warp could be an exception, and especially dangerous. Technically they're not moving, the space around them is so there may not actually be any air resistance to burn them up in the atmosphere, and they would impact the planet with an incredible force. They wouldn't be a precision weapon at all, and really only used for genocide.
As far as detecting a ship in flight, there is currently a prototype detector called the [White–Juday warp-field interferometer.](http://en.wikipedia.org/wiki/White%E2%80%93Juday_warp-field_interferometer) A perimeter of sensors around the solar system may work, it takes at least 2.5 hours for an object at the speed of light to get from neptune's orbit to the earth's orbit, so that may be enough time to fire missiles at it, or prepare for its arrival.
] |
[Question]
[
Quick refresher ...
I'm considering the two basic strategies of child-rearing. R-selection, meaning you have lots of offspring and don't care for them much; and K-selection, meaning you have a few offspring and take very good care of them. Humans are *the* poster-species for K-selection, and most fish are a great example of R-selection -- they spew out zillions of eggs and then abandon them (either at laying time or hatching time, depending).
So...
Let's imagine we have some kind of clever land-octopus alien which casts its eggs to the wind. They want to evolve intelligence and build a civilization, but will have severe problems building any kind of continuity. Is there any hope for them?
Edit: Distinction from possible-duplicate question is this... I'm questioning whether they would even be able to group together. Aside from some (creepy, scary) insect tribes, most R-selecting land creatures are asocial and see the offspring as competition or -- heck! -- snacks. A possible pattern that might be interesting is fish schooling; the fish don't care for their young, but they clump together as they grow anyway. That might be a template for tolerance of one another's presence.
Another thought is that you might have these R-selecting parents *herd* their own offspring. Offspring are nimble enough to catch small prey that parents cannot, so parents keep them around, eating the biggest near-adults and gaining benefit from prey sources that they can't catch themselves.
[Answer]
Then, on a given day, an adult specimen has a brillant idea:
>
> So much eggs and infants wasted and so many hard work to do here at my farm...
> Why not farm those eggs and infants in order to make most of them reach adulthood? This will maximize my profit!
>
>
>
And subtly your R-selection begins to switch to K-selection. Then, the K-selection people would use technology to outnumber the R-selection ones driving them to extinction.
Except if something makes that be a really bad, impracticable, inefficient or impossible idea. There must be some important selective pressure that prevents a switch to K-selection and keeps R-selection favourable.
Some species uses R-selection here on Earth for many possible reasons like:
1) The adult can't really take care of its children without other dramatic adaptations to its body.
2) The adult can't even properly take care of itself or its sexual partner. No way to take care of offspring. It would be just easier to produce zillions of offspring and even if 99.9% of them don't reach adulthood, there would be enough for the next generation.
3) 99.9% of the offspring is sterile. Specimens able to reproduce are an elite. This happens with ants and bees, for example.
4) 99.9% of the offspring has disabilities and malformations that render them unable to survive childhood.
5) The adults dies shortly after the production of offspring and won't be able to ever see them. This happens with some insects that live for many years as eggs or infants and just a few days as adults.
6) Eggs and offspring are produced in the environment without the parents even being unable to acknowledge that they did that. This happens specially to plants and fungus, but may also happen with some fishes.
7) The eggs must be implanted in a place where the adults can't live. The infants and adults live on separate environments and would quickly die if one invades the environment of the other. This for example, happens to mosquitos, where larvas live in water and adults live in land and air.
8) In order to become an adult, the child must be able to encounter enough quantity of a rare resource or be able to develop a hard and costly skill.
9) The males and females are radically different and one of the sexes for some reason greatly outnumber the other. Only members of the elite sex are intelligent.
10) The males and females are radically different and one of the sexes for some reason greatly outnumber the other. Only members of the elite sex are **not** intelligent.
11) The males and females are radically different and one of the sexes for some reason greatly outnumber the other. Both sexes are intelligent.
12) Infants compete harshly and promptly kills each other until the last man standing.
13) Probably other reasons that I don't know or just forgot about.
Numbers 1, 2 and 5 are probably unable to ever evolve some appreciable form of intelligence at all.
In the case of 3, there would not even be the mentioned brillant idea because farming offspring is exactly what they are doing as a species, so they already somewhat care about their childs and this is not what you are looking for.
On number 4, they might farm offspring and select and care only for those that are able to reach adulthood, disposing the rest.
On number 7 and 8, once the species is able to gain superior intelligence, it will start farming their eggs and possibly either revert to K-selection or to some artificial form of number 4 - "*Select the best one childs, kill the others. We know, this is sad and cruel, but we have no choice, we can't raise everybody.*"
In the case of 9, 10 and 11, once the species becomes intelligent, the members of the elite sex receive great care and attention of the offspring while the members of the opposite sex are artificially selected with all the rest being discarded (like 4). Don't expect that they will even think about closed marriage, genre-equality of sexual freedom, this would be really absurd ideas for them.
In the case of 12, through the use of the brillant idea, intelligent parents would separate all or most of the offspring and raise them separated. This will make them tend to switch to K-selection after some millenia of widespread offspring artificial selection (like 4).
Number 6 is the best:
>
> A male is selling some items in the market. A female customer just comes in. After some seconds of a friendly talk, she gives him the cash and gets the item she just bought. He thanks her and she answers with a smile and leaves. They have no idea that they just had sex and their fecunded eggs are now being carried away by the wind, but won't be surprised if someone tells them.
>
>
>
[Answer]
## An example in fantasy: the Grik
In Taylor Anderson's series *[Destroyermen](https://en.wikipedia.org/wiki/Destroyermen)*, the Grik are an r-selected species of reptiles which have an impressive (and mighty powerful) civilization; the trick is that in their lifecycle they have two phases: an eusocial non-sentient phase when young, sometimes followed by a fully sentient and sapient phase when older. The [eusocial](https://en.wikipedia.org/wiki/Eusociality) young make brave and obendient soldiers or tireless if unskilled workers, while the actual civilization is built and maintained by those relatively few fully sapient adults.
(For completeness, *Destroyermen* is an entertaining parallel-world adventure series of novels, following the crew of an American *[Wickes](https://en.wikipedia.org/wiki/Wickes_class_destroyer)*-class destroyer which is displaced to a parallel timeline during the [Second Battle of the Java Sea](https://en.wikipedia.org/wiki/Second_Battle_of_the_Java_Sea) (March 1942); in that parallel timeline Earth is inhabited by two native sentient species, the above-mentioned warlike reptilian Grik and the relatively peaceful Lemurians, plus the humans brought there by several timeline-displacement events. Besides the expected military fantasy, it includes at least two cute cross-species romances.)
[Answer]
You seem to be focusing on continuity as in having parents to transmit things to their offspring. I don’t think this is the best angle for this.
Ants are a good example of r-selection, and seem to be doing pretty well without teaching anything. But they are unlikely to develop a civilization because of their limits.
r-selection is based on creating a large amount of offspring, which requires the offspring to cost as few resources as possible.
Humans reproduce usually one offspring at a time because human babies are costly to make. That’s why we care so much about each of them. Human brains are in fact so big that human babies are born before they are able to sustain themselves and finish their development outside the womb, or else their head would end up being too big to fit.
Unless you find a way to have your species develop a civilization — which implies culture, technology, etc. — without a big brain — decentralized brains, for example — you will have a big problem.
[Answer]
[Negligible senescence](https://en.wikipedia.org/wiki/Negligible_senescence) (or natural biological immortality) might do the trick. Our huge K-selection bias has led us to civilization and technological development, as you intuit, at least partly because we desire survival/persistence and good lives for our heirs. But if there's no strict requirement that you'll ever personally die, personal survival and prosperity might provide all the motivation one needs to build a civilization. Of course, immortal in this context doesn't mean unable to die, it just means means no degenerative aging and inevitable death from old age.
It may seem at first blush that a biologically immortal r-selectionist would have little reason to organize socially. However, readers of Thomas Hobbes will recognize that one of the strongest motivations to form civilizations is to keep people from bonking you on the head in your sleep and taking your resources. So, so long as the species experiences necessary periods of dormancy *which remain occasionally necessary throughout an individual's life*, there's more than enough reason to organize socially. (On the other hand, if you're done with dormancy after metamorphosing into the adult form, that provides no civilizing motivation for an r-selectionist at all.) For a biologically-immortal r-selectionist, friendship is the single-greatest survival-oriented innovation I can imagine.
[Answer]
I would suggest something close to how gargoyles in the animated series by the same name approached child rearing. Gargoyles laid eggs but an entire clan would raise the child and traditionally never acknowledged genetic parental relationships... all children of the newest generation were raised by the collective clan. How punishments and the like was handled was never specified or whether grouping was encourged. The relationship of parents and child was mostly put into a generational gap disagreement where the lead character's daughter turned up. Having been raised from hatching by humans, she wanted parental attention, which was difficult for the father to accept. According to series creator, there was a father/son pair in the core cast, but it was never discussed in series and you could easily miss it. Also, according to the series creator, incestual relationships among siblings or parents was discouraged by a "scent" marker that was only unpleasent to those of the same genetic lines.
Not sure this counts, as it has aspects of both (the R-K hybrid is further mixed by a difficult gestation period (and only one idividual at a time, with a very rare identical twin) and long childhood. That said, this could be easier if the society had community child-rearing and less qualms about childhood death (vacinations would probably be administered in early maturity rather than early childhood, Spartan Parenting is the norm (either be smart or starve)). As a result, the society would likely be seen as barbaric by human standards in some regards, though nepotism and marriage might be unknown to them (no knowledge of who's my kid and no reason to stay with my mate for the sake of the children. This doesn't rule out any favoritism from an elder authority to a younger though... but they would see something in the younger they value and want to foster). They would also probably have a quasi-democratic government as no one is special beyond they lasted longer than their siblings and "weak" bodies would be discriminated against. Parents certainly wouldn't be adverse to letting the brood play with lawn darts and toys certainly would be much more dangerous.
[Answer]
You can still build a civilization with this kind of reproductive system. You just have to gather individuals in group where they can share their knowledge, specially to younger individuals.
So in this scenario, the octopus hatch alone in the wild, with a high infant mortality rate, but the survivor will integrate a group of older octopus, allowing to pursuit civilization.
[Answer]
In Heinlein's *Stranger in a Strange Land* the civilized Martians produce many offspring who live outside of civilization for some time and most of them die, the survivors are then adopted into civilization.
In Futurama: Kif's species produces a bunch of tadpoles, and gives minimal assistance to get them to water, but then lets them grow on their own (presumably with many dieing) for years until they grow legs and come back on land. Zoidburg's species has a mass spawning the precludes parents caring for their offspring.
The main point is intelligence. If your species has enough of it for adults to have civilization it doesn't really matter how you get new adults so long as there can be a continuity of adults, or they can at least pass ideas and infrastructure to the new generation.
[Answer]
Not unless they were natural readers.
The march of progress only marches if people, as a whole, get smarter over time. In order for an R-Selection species to grow in average intelligence would be if every generation read what the generation before had written.
We take care of our elderly, and have done for a long time. By doing this, they can pass on their knowledge to people who are young enough to use it. They make less mistakes, ergo better survival rates overall.
Without the ability to pass on knowledge, we don't get smarter. You'd need your species to instinctively know how to read and there's no science I know of to suggest something that intricate could be passed on genetically. However, language is definitely "in our DNA" in that we know instinctively how to learn a language and the language we learn is just whatever we're exposed to. So your aliens COULD, theoretically, only communicate in visual cues allowing a writing system to be similar enough to their "vocal" communication that they could instinctively pick it up easier.
It all depends how much "Suspension of Disbelief" you're going for.
[Answer]
Another possibility in which r-selection aliens build a society is if the aliens passed down knowledge through hereditary means, or other automatic means. Passing down knowledge through genetic means doesn't seem possible, but what might be a possibility is if the aliens reproduced in some way that would have them begin life neurally connected to their parents. If their nervous systems were connected at the start of life they could carry forward some knowledge from birth, and then be completely antisocial while still developing to some point. They would again pass on the knowledge when reproducing, so it would not die with them, and technology could develop, though not necessarily a very civilized society.
If the offspring developed inside the parent to a degree they could also have a connection to their parent's nervous system, similar to how the umbilical cord forms a connection to the parents circulatory system. However longer pregnancy generally is linked to k-selection, though I see no reason the adult couldn't abandon the offspring at birth.
One possibility that could have k-selection pregnancies is if the adult died in, shortly before, or shortly after childbirth. This would mean the aliens remained r-selection. In this scenario I assume the children would absorb large portions of the adult as they developed. This would also mean knowledge would likely only be passed down by which ever gender had the pregnancy.
] |
[Question]
[
**Background**
In a galaxy not so far far away....
The [Andromeda](https://en.wikipedia.org/wiki/Andromeda_Galaxy) galaxy is presided over by two major powers - the Y'Ing and the Y'Ang. These powers have existed together but never integrated with each other into a galactic whole. They have been in a Cold War state for millennia. In spite of this, they have roughly the equivalent state of technology and share of the galaxy and share the galaxy roughly equally:
[](https://i.stack.imgur.com/PHfgs.jpg)
For the past 5 years, the Y'Angs have been mobilising an invasion force with the aim of taking the whole galaxy over, once and for all.
**Facts** (at least in this fiction):
* The Andromeda galaxy has an average radius of 220,000 light years
* Faster Than Light travel exists
* Faster Than Light communications also exists, and transmits twice as fast as travel does
* It takes six months for a message to travel from the core to the rim
* Travel and comms get progressively more difficult as you reach the core (one or more supermassive black holes has something to do with this)
* The Y'Ings and the Y'Angs each have about a habitable billion star systems and a billion [Super Star Destroyers](http://www.starwars.com/databank/super-star-destroyer) and a wide range of supporting fleets
* FTL in this fiction **does** break physics/time. Think of Star Wars/Star Trek where FTL is simply getting somewhere else really, really quickly
* Comms cannot be transmitted or received while a ship is in FTL travel
* Defending forces have sensors that can detect enemy FTL travel (but not comms) within 10 light-years of the sensor
**Y'Ing/Y'Ang political personalities** - Analogous to America/Russia during the Cold War. Y'Ang is basically Russia.
**Question**
How do the Y'Ings defend against the Y'Ang invasion? What command structure would be in place, and what would a high level defence strategy look like?
[Answer]
# How to defend against the Spanish (Y'Ang) Armada
**1. Have spies find out when the Y'Ang Armada is setting sail.**
This would make the situation a lot easier. In the case of the Spanish Armada, the fact that the Pope granted the Spanish soldiers indulgences and allowed King Phillip of Spain to collect a crusade tax was kind of a dead giveaway. The logistical requirements for collecting a billion super star destroyers in one spot are pretty incomprehensible, so I think you could get some advance warning.
Speaking of which...have you looked at how much a super star destroyer weighs? [These nerds](http://www.st-v-sw.net/STSWvolumetrics.html#mozTocId967234) say ~10e13 kg. Times a billion star destroyers is ~10e22 kg which is basically the mass of Luna. You could potentially upset the orbits of a system with a fleet that big. Better spread them out a bit.
**2. Get advance warning of the fleet's appearance**
From [Wikipedia](https://en.wikipedia.org/wiki/Spanish_Armada):
>
> The fleet was not sighted in England until 19 July, when it appeared
> off The Lizard in Cornwall. The news was conveyed to London by a
> system of beacons that had been constructed all the way along the
> south coast.
>
>
>
Beacons do 'signal' at the speed of light, but lighting one beacon then another in succession isn't really the fastest. So your FLT comms plus some long range sensors should do the trick. The English fleet was stationed about 90 miles away from The Lizard in Plymouth, so it was on hand to react quickly. The bottom line is, while the Galaxy is a big place, due to the nature of FTL travel there may only be a few places the enemy could reasonably show up. Same with the Spanish Armada; Britain has a lot of coastline, but there were only a few directions the Armada could reasonably approach from.
**3. Concentrate your forces**
In order to threaten an invading fleet of a billion, you need to preserve your core fleet in one group. While the nature of your naval combat is uncertain, the effect of superior numbers has had a multiplicative effect for all naval battles since the invention of gunnery. That is, since with gunnery you can engage at range, any fleet at a 2:1 (or greater) disadvantage will quickly be pounded into space dust since the enemy has so many more weapons. This contrast with, say, the movie *300* where there were a series of one on one (or rhino/giant/monster on one) engagements at the front line. If the 300 fought with guns, they would have died in a hail of lead 15 minutes into the movie.
The English managed to gather many of their best and brightest admirals together, such famous figures as [Francis Drake](https://en.wikipedia.org/wiki/Francis_Drake), [Charles Howard](https://en.wikipedia.org/wiki/Charles_Howard,_1st_Earl_of_Nottingham), and [John Hawkins](https://en.wikipedia.org/wiki/John_Hawkins_%28naval_commander%29). By getting all the far-flung fleets and privateers concentrated the English fleet was able to put up a fight. And this far flung fleet could only be gotten through the use of the spies/pope to give advance notice of the *intention* to invade.
**4. Hope for the best**
Anyone who plays grand strategy games knows that once the battle starts, you just hope for the best. You can set up the fight at a location and time that advantage you, but when the metal meets the meat, anything can happen.
**5. Attrition is your best friend**
If you did win, great! The Spanish Armada was beaten, not broken. But then it was forced to retreat up and around Scotland (as the English fleet was blocking the Channel passage). This was not good, since it was now late September and storms were brewing off the Hebrides and the coast of Ireland. Nearly half the fleet got wrecked on the home voyage. The obvious analogy here is that if you win, try to cut off the enemy's easy escape path. Since the fleet is concentrated, this doesn't require much FTL capability; the victorious Admiral just needs to keep hounding the defeated enemy fleet until calamity befalls them.
If you lost, its ok! Its not over yet. That billion ship fleet still needs food and supplies (what happens to morale when the toilet paper runs out?) for untold trillions or quadrillions of crewmembers. If they do succeed in breaching your defenses and wrecking havoc in your core territories, you can harass their supply lines, play scorched Earth, and make planetary sieges as difficult as possible. Think of the Japanese Kamikazes, the Romans not giving in after Hannibal destroyed army after army, and the Russians burning Moscow before Napoleon arrives. This too does not require massive coordination, small forces acting independently are more dangerous as guerrilla forces. The defeated Admiral needs to get what remains of his fleet to safety so it can be a threat in the future (like Washington retreating to Valley Forge).
[Answer]
There is really **only 1 problem**: communication speed. This means that due to long lag times you cannot do a central command system. Here is how I would defend:
**Step One: Balance,** use your [intelligence agencies](http://www.historynet.com/world-war-ii-ultra-the-misunderstood-allied-secret-weapon.htm) (preferably three letters) to find out where the enemy forces are. Use that to move your forces around to counter.
**Step two: Draw them in,** Unless you want to do [preemptive](https://en.wikipedia.org/wiki/Preemptive_war) strike, you will be reacting in the first stages. So go [defence in depth](https://en.wikipedia.org/wiki/Defence_in_depth) (in 3D, maybe 4D). Draw them in, cut them off, defeat them in [detail](https://en.wikipedia.org/wiki/Winter_War#Finnish_tactics).
**Step three: Let lose** those soldiers that have been training for so long. Give the local commanders the space they need. Don't go [president Johnson](https://en.wikipedia.org/wiki/Lyndon_B._Johnson#Vietnam_War) (or a long list of political leaders that tried to wage war from on high)
**Step four: Jus in bello** Treat the soldiers you capture [well](https://en.wikipedia.org/wiki/Just_war_theory), that will make, barring some strange values, more willing to stop fighting. Sun Tzu has some ideas on that.
**Step five:** Fiddly bits; how to do the above with the tech you described.
[Answer]
## Defensive strategy
The Y'Ing High Command will want to induce the Y'Ang to not attack. After all, you can't lose the fights that you don't engage in and the best wars are the ones where you don't have to fight. That said, the price of this war will be trillions of deaths and the destruction of entire star systems. There are four options for how this Cold War will end: It will continue as it is, it will detente without bloodshed, it will escalate and burn the galaxy, or the two empires decide that it's easier to just merge.
## Y'Ing Objectives
1. Preserve political autonomy
2. Preserve population
3. Preserve industrial capacity
## Y'Ang Objectives
1. Remove political autonomy from the Y'Ing.
2. Preserve population
3. Preserve industrial capacity
This could turn into a Dune-style [War of Assassins](http://dune.wikia.com/wiki/War_of_Assassins) where there need be no bloodshed of the common people but a lot of the empire leadership dies. Given the extreme costs of open conflict, empire leadership may decide that this is the best course. For the lives of the quadrillions of citizens of each empire, I hope they choose this path.
## Defensive Screening
Establish screening pickets along the border and significantly above and below the galactic plane (don't want the Y'Ang to cheat and just go off-plane to avoid detection) There's enough population and industrial capacity to completely saturate all space with redundant detection posts. Extend these listening posts into Y'Ang territory as well. Replace listening posts as the Y'Ang detect and destroy them.
## Saturate the Y'Ang Political and Military Organization with Spies/Informants
Knowing when a Y'Ang fleet departs from dry dock is a significant advantage when planning counter-movements. Any kind of positional information on enemy fleet or troop dispositions will help immensely.
## Develop a "Nuclear" Triad
Develop the equivalent of nuclear submarines, bombers and ICBMs (heh, they'd be IGBMs, Inter-Galactic Ballistic Missiles). The threat of overwhelming force should make the Y'Ang think twice before launching an attack.
IGBMs - Position autonomous "nuclear" warheads near strategic targets. With the industrial capacity of the Y'Ing, it's possible to build thousands or IGBMs for each target.
Bombers - Position significant attack resources off the galactic plane with orders that if war broke out, they are to attack their targets.
Submarines - highly capable but small fleets of attack ships, each ship capable of [glassing](https://en.wikipedia.org/wiki/Trinitite) a planet, that constantly patrol through Y'Ang space without making threatening moves against any particular Space is huge so catching these patrols will be incredibly difficult.
## Command and Control Structures
Trying to manage a naval fleet containing one billion Super Star Destroyers plus billions of support craft can't be done by one human. This many SSDs is only two orders of magnitude away from the number of cells in the human brain. Including support craft, the number of ships in the navy *is* the number of brain cells in the human brain.
The only solution to this is to automate everything about fleet command and logistics. I can't imagine the compute or storage resources required to do this but it's going to make the combined might of AWS, Google Compute Platform and Microsoft Azure seem like pet projects that junior engineers do as warmup projects.
But, luckily, the Y'Ing and the Y'Ang have had centuries to advance their distributed computing prowess and [Strong AI](https://www.ocf.berkeley.edu/~arihuang/academic/research/strongai3.html). It's entirely possible that there will be no human commanders at all, just AIs.
## Research Objectives
Pour as much money as possible into FTL Interdiction fields. Mobility is the key to winning most any conflict. If you deny your enemy the ability to move, you make them that much easier to find and to kill. Without interdiction fields, there's nothing to stop an IGBM from popping out of FTL right on top of your industrial bases and political centers with zero warning.
## Make it in the best interests of the Y'Ang businesses not to attack the Y'Ing
If your business depends heavily on trade with the opposing empire, you'll be highly motivated to pressure your politicians to avoid armed conflict. The greater the financial and business relationships between the two empires the greater the resistance to any conflict that will disrupt those relationships.
As the Y'Ang chief executive will find, (s)he won't stay in power long if many major trade unions withdraw their support or start to actively undermine your administration.
## Assumptions
Two billion known systems. All systems are known to both sides. All major planetary industrial centers known. Significant mobilized orbital industry.
Ring shaped battlefield, no one goes through the center.
Each battleship has a crew of ~50,000. Assuming that support staff is 8x the ship crews (assumes higher because of the greater complexity of space fleets.) This means that there are 50 trillion sailors in the Y'Ing navy on just the Super Star Destroyers. The naval support staff is 400 trillion people. Earth's infantry requires between 5x and 6x people for each infantryman.
USA military is about 1.8 million compared to 318 million. 0.5% of population is in the military. Estimated population of the Y'Ing empire is 1e+16 people or 1 quadrillion people. 1 quadrillion people.
Imperfect information game state, no one knows everything about all the pieces.
Mixed Industrial Mobility - Most planetside industrial capacity will be static. Reasonable to assume that orbital industrial facilities can be moved, given that there are a billion 1.6Km long battleships on each side.
First, this is unthinkably huge industrial capacity. On Earth in WW2, the US made approximately [47 billion bullets.](https://history.stackexchange.com/a/1721/12928) That's only 47 times more things than the number of kilometer long battleships this civilization has made. Their bullet making capacity is in the quadrillions of bullets, easily.
[Answer]
The other answers cover strategy at length, so I'll answer command structure.
Obviously, you have a HQ. Every bit of information eventually gets back to them, and they are in charge of the general direction of the war and coordinating all the fronts. However, the further away they are from the front lines, the more out of touch they will be.
Given the nature of the galaxy, I'd foresee the war bubbling out in both directions around the core (assuming the core is untraversable like in Star Wars or other like galactic structures). So you'd have two Fleet Admirals. One for each direction. However, they would be able to override HQ's orders since they are more in touch with whats going on in their galactic direction.
Then, considering the time radius of the galaxy, you'd have maybe 5-6 Vice Admirals each with about 1 month/segment of space-time. They would be more in touch with their region than the Fleet Admiral, so they would be able to override their orders.
Finally, you'd have a couple Rear Admirals in each Galactic Segment who would report to their Vice Admiral, but ultimately be in-charge of their subsection.
Under them, the command structure would be as it usually is.
The idea is to have a command local enough for the time distortion to not be an issue. But you also need someone coordinating the entire war, otherwise it's just two dozen different groups fighting another two dozen different groups. This revised structure leads to an odd partially inverted hierarchy where one guy can ignore any order from lag-space. However, as soon as their commanding officer is within a certain distance (they are out of lag-space), the order needs to be followed.
Obviously, any order that tries to detail the means as well as the ends will fail at any rank above Sub-fleet Commander (think a squad leader in an army). So you need people directing the goals of any given Sub-fleet, and then the Sub-fleet reports up the chain so that everyone is in the loop.
[Answer]
## The defence strategy:
Three lines for defense:
1. Scattered recon
2. Small fleets
3. Big fleets
As the enemy approaches line #1. relays the information about the movements. #2 dodges the enemy and line #3 stops it. Line #2 joins the battle from the rear and behind. #1 and #2 have effectively cut the enemy off the supply.
This is only why the enemy cannot blitzkrieg. It will need to clear off at least #2 before it can penetrate further into the territory. To do this the enemy needs to scatter its troops. The idea how the scattering can be utilised is to locally create advantages of having more troops. Because the enemy would like to push, it will have to do some sacrifices to get anything done against line #1 that retreats all the time and the line #2 that has enough big fleets to eliminate too small scatterings.
Command structure wise the fleets have a simple missions they can carry out without micro-management. Thus they will carry out their missions automatically. Line #1 reports to line #2 and they report to line #3 that report to HQ.
This strategy eliminates too long FTL jumps, because you do not want to crash with missiles or whatever projectiles that are a real risk behind #1 line. Story-wise it can explain why there is a cold war and multiple offences without success.
This defense strategy corresponds closely to: panzer recon - reserves - arty structure. If the enemy is not much stronger they do not want to go too deep, because recon orders artillery bombardments and the reserves can block the enemy for the artillery to do more damage. Panzers with the recon make it so that they can escape and are scary against soft targets (like supply). I could easily see this becoming a stale mate if there would not be air forces. In your space situation there is not something similar to break the structure.
[Answer]
The primary issue with being on the defensive in a galactic scale war is that while you must be everywhere to defend, your enemy only needs to attack one or two places and can do so with overwhelming force.
The obvious solution to this would be a preemptive strike on the Y'Ang industrial worlds and repair and supply depots.
However, if this is not politically or militarily feasible, (There may be political opposition to starting the war and the targets I suggested are by definition surrounded by warships) your best option is to create a system defense mechanism similar to what the Havenites used in David Webers Honorverse series, with some additions made possible by the FTL comm system.
This will enable you to defend with a minimum of ships and simultaneously counterattack.
---
For system defense:
1. Use a Moriarty unit (pre-fabbed sublight unit with nothing but missile control and the best stealth you can give it.) I suggest multiple Moriarties per system as they are toast as soon as they are detected.
The purpose of the Moriarty is to control a TON of missile launched from pods. While pod launched missiles will have a much lower initial velocity then their ship launched counterparts, they have two major advantages over ships for system defense. First, with the Moriarty you will have the ability to launch missile volleys orders of magnitude larger than your enemies. Second, if you are using the pods in a system defense doctrine, the size constraints that limit them in ships are largely gone, enabling you to use more powerful drives and warheads. This means that while your missiles will have a much lower initial velocity (there are probably ways to overcome some of that) they will have a *much* higher final velocity and you'll be using more of them.
Think water guns against a tsunami.
2. FTL detection: As far as system defense goes, the FTL detectors will only give you 24 mins of warning that a potential enemy of unknown strength is heading in a given direction.
While better than nothing, the lack of information will make it difficult to use as anything other than an early warning for the system that will be attacked.
While you can deal with this by placing sensor platforms on areas that the Y'Ang are likely to use and extrapolate the targets from the data, the fact that it cannot detect the size of the enemy fleet means that it will be difficult to prioritize what systems to send your fleet to defend as the Y'Ang can simply send a drone equipped with an FTL drive across the galaxy setting off any detector in its path.
My suggestion to deal with this would be either some sort of FTL intercept device (kind of hard to imagine that working without a lot of luck involved) orrrrr.. (Drumroll please) More Moriarty!!!! (I love missiles!!)
Joking aside the real reason not to rely on this as anything other than a short-term warning system is that the only place the Y'Ang *absolutely must end up in* will be your systems. *Any* other assumption can be fatal. To plan based on what you think your enemy should do assumes that they have the same constraints that you do. (Enter Hannibal)
This does not mean that it's not worth doing, only that it should not be relied upon, as unless you can cover half the galaxy with sensor units the Y'Ang can avoid them. Intelligence (spies) will work much better as a method of tracking enemy movements.
---
Command structure: @amflare did pretty well on this. All I want to add is that if the Y'Ang are as expansionist as you make them sound, there may be opportunities for your spies to start some "civil unrest" (read riots, mayhem, and possible revolts)
I'd like to paraphrase Sun Tzu on this one. Three steps
1. Get someone competent
2. Get them as much of what they need as you can
3. Get out of the way
] |
[Question]
[
**Closed.** This question is [off-topic](/help/closed-questions). It is not currently accepting answers.
---
This question does not appear to be about **worldbuilding**, within the scope defined in the [help center](https://worldbuilding.stackexchange.com/help).
Closed 7 years ago.
[Improve this question](/posts/65627/edit)
Being eaten is obviously not a process most organisms can survive. But assuming one is swallowed whole, and isn't injured before reaching the stomach, what actually ends up killing them? Acid? Heat? Pressure? Lack of oxygen? Would it necessarily be painful, or could you peacefully fade away into soup?
Edit: If it makes the question less off-topic, I'm particularly interested in fictional carnivorous humanoid mammals somewhat resembling anthropomorphic wolverines swallowing rat or weasel sized mammals. They digest the creatures they ingest wholesale, bones included.
[Answer]
## In-ability to breathe.
I put it that way because it's going to be a mixture of lack of oxygen and excess of CO$\_2$. If it's a human getting swallowed by a large creature with a similar digestive system you'll also be burned by acid, but it won't kill you faster than suffocation. So, you'll die gasping in the dark while being burned by acid. The heat and pressure will likely be the least of your worries, but they're certainly not going to increase your comfort.
[Answer]
Assuming a humanoid could swallow a rat alive and it gets to the stomach without being asphyxiated by being compressed by the peristaltic action of the esophagus, it will die from lack of O2 in the stomach. The stomach has gastric fluid that is mildly acidic, but mostly it lacks air. Gas in the stomach is usually released via burping and this is often a by product of carbonated fluid or air whipped into foods, very little oxygenated outside air is ingested under normal circumstances. So the rat will find itself in a gently squeezing sac mostly filled with liquid. Even if it could push out it's legs to make space, there won't be much, if any, oxygenated air for it to breathe, so it would asphyxiate quickly.
Of course if it was conscious on the way down it could have torn the crap out of the esophageal lining, and could possibly bite its way through the stomach lining if swallowed fast enough. Escaping into the peritoneal cavity won't really help as there is no breathable gas there either, but if sufficiently motivated and good at holding it's breath it might be able to dig through the abdominal wall to reach the outside, especially if a bright light is transilluminating the way. So the eater is gonna have a rough time of it if he didn't stun the rat first...
[Answer]
It depends a lot on the animal doing the swallowing and the thing being swallowed.
some like whales and crocodiles have so very destructive digestive systems, things like crushing crops, extreme pressures and very aggressive acids.
And different animals are resistant to different things, some animals like turtles are resistant to both suffocation and crushing, or like some worms are resistant to acids.
Usually it is either suffocation or crushing
The size difference is important. If there is a big difference in size it is usually crushing forces that kills. For smaller differences it is usually suffocation.
As for you question at the end, mammals (like most heterodonts) don't do a lot of swallowing whole, your rat will be chopped into several pieces by the teeth or chewed into a pulp before swallowing.
] |
[Question]
[
I was bumming around Reddit the other day when I came across a discussion talking about how laser guns in Warhammer 40,000 have appreciable recoil, enough that a laser sniper rifle was described as having a kick strong enough to leave a bruise on ones' shoulder. Now I know 40k plays fast and loose with the laws of physics even compared to most science-fiction series, but this seemed incredulous even to me. It was my understanding that laser weapons would have no recoil since photons do not have appreciable mass, only momentum, or the amount of force they would apply to the firer would be absolutely miniscule. I've also not heard much about real life lasers ever having significant recoil.
What's more surprising is that nobody in the actual threads seemed to be able to figure out whether laser weapons would have appreciable recoil. In both the discussion and another linked blogpost, people propose all sorts of explanations saying "yes it would have recoil", "no it would not have recoil", or "yes but the recoil would be slight", and it's hard to tell which are accurate to real life physics. The links are posted below if anyone is interested in the actual explanations given.
<https://www.reddit.com/r/40kLore/comments/kc3ddl/why_do_lasguns_have_recoil/>
<http://thevirtuosi.blogspot.com/2010/04/today-id-like-to-approach-question-near.html?m=1>
So my question here is **would a laser weapon have significant recoil or not**? And by this I mean an actual laser weapon, not a particle gun dressed up as a laser or misidentified as one like Star Wars blasters.
[Answer]
No, while there would be recoil, it's not enough to be perceptible. For example, according to <https://en.wikipedia.org/wiki/Radiation_pressure#Solar_radiation_pressure>, the radiation pressure of the Sun over a square meter is 10 μN. So, a laser with 100,000 the power of the sun over a square meter beam or 1,000,000,000 times the power of the sun over a square centimeter beam would only generate 1 N of force, which is about the same force as holding 1 apple in your hand.
[EDIT] AlexP brings up good additional information in a comment. The energy of the Sun over 1 square meter is ~1,360 Watts. Plugging those into our hypothetical 1,000,000,000x power beam above, that's 136 MW. One megawatt is one megajoule per second and a megajoule is roughly equivalent to energy of a stick of dynamite. Therefore, keeping this hypothetical beam on for one second delivers 136 sticks of dynamite to the target every second for a peak recoil force of 1 N. That's far more powerful than a fictional "laser sniper rifle" would be.
[Answer]
A laser would not have recoil enough to affect your aim. Depending on the needs of your story, there may be various **secondary** causes for recoil. Perhaps "imparted motion" would be a more accurate name.
* The laser projector has spaces inside that are open to the air. As the laser passes through the air heats, expands, and wants to evacuate through whatever holes are available. Any moisture/humidity in the air will gasify and expand, essentially creating a steam jet. If the only opening is the "muzzle" then that's where the hot+expanded air will go, providing a force backward from the beam. Possibly a surprise for a protagonise who just crawled out of a river or rainstorm and now has water inside their weapon.
* The laser has some kind of cooling system, perhaps liquid-based which means a pump to cycle the fluid through a radiator and back to the gun to cool it again. Its possible the pump has a rotational "kick" to it at startup in opposition to the direction it turns. A soft-start in the pump's motor would mitigate this.
You could also have inertia in the flowing liquid or fans, which provide a precession effect when trying to turn the gun. Not quite recoil, but it could be a perceptible effect.
* If you require some funky consumable, eg the Primary Beam being an overloaded ray-projector in Lensman and needing to be replaced like a camera flash bulb, then the moving mechanism to eject and load a new one can have recoil. This also lets you use tropes like being "out of ammo" more than "flat battery"
[Answer]
It is a [explosive pumped laser](https://en.wikipedia.org/wiki/Gas_dynamic_laser) and the hot combustion products are vented mostly in the direction of fire after the shot. Some attempt is made to balance the venting and limit the perceived recoil by using differing variations of muzzle brakes, but some still remains.
[Answer]
# Recoil: YES. Measureable? NO
Thrust/recoil wise, your laser weapon is just a photon rocket.
There is a very simple rule for a photon rocket: 300 MW/N
This mean that a 300 Megawatt light photon weapon will impart a recoil of 1 Newton (3.6 ounces)
And that applies only while it is continuously firing.
How strong is 300MW continuous beam?
An Industrial laser cutter runs at about 5000w, to cut through 1.3cm Stainless Steel.
Your laser rifle is already 60 000 times as strong as that.
And for that, it has 3.6 ounces of recoil.
[Answer]
Moving this to an answer as suggested by [Criggie](https://worldbuilding.stackexchange.com/users/13944/criggie)
One reason a laser weapon might have recoil is for the User Experience - capitalised, because it's a design choice.
We live in a world where cars have carefully engineered engine noises, vacuum cleaners are noisier than they need to be because people view the quiet ones as less effective, and people choose tactile user interfaces that give real feedback.
It's not a stretch to imagine that for people coming from projectile weapons, it doesn't *feel right* firing something with no recoil and no visible effect. If physical feedback is engineered in, it will make people think it's more effective - and so sells more.
] |
[Question]
[
What technology (at minimum), devices or minimum civilization development is needed, so that an individual member of this civilization would be able to detect that some star is going supernova?
My question is inspired by "[The Inner Light](http://en.memory-alpha.org/wiki/The_Inner_Light_(episode))" episode of Star Trek Next Generation (though [I don't know what civilization development level is presented there](https://scifi.stackexchange.com/q/77318/7885)).
I just want to know what must be invented by a civilization, to be able to detect [this kind of threat](https://worldbuilding.stackexchange.com/q/3615/36)?
[Answer]
When people think of supernovae, they often only think about the visible light emitted during and after the explosion. However, if you restrict yourself to observing in the optical part of the electromagnetic spectrum, you'll lose a whole lot of information. There are a few different astronomical messengers scientists can use to study a supernova.
## Years in advance
In the final stages of their lives, massive stars tend to exhibit violent behavior, such as chaotic episodes of mass loss. The final stages of fusion (neon, oxygen and then silicon) take years down to days to occur, compared to the billions of years during which the Sun fuses hydrogen. [Several mechanisms in these late stages](https://www.cfa.harvard.edu/events/2016/sackler/index/talks/SMITH.nathan-sackler.slidedeck.pdf) could lead to mass loss events. These would be detectable in the optical and infrared bands, appearing as dimming as ejected dust enshrouds the star.
This was one of the reasons it was briefly thought that Betelgeuse could be in its final months of its live when it began dimming this past autumn. While the dimming is likely due to a major mass-loss event, it isn't necessarily due to one of those uber-late-stage mechanisms. In other words, a single large mass loss event isn't evidence of a supernova, but a sustained period of activity could wag its head indicatively.
## Days to hours before
In the [hours to days](https://worldbuilding.stackexchange.com/a/31595/627)) before a supernova, the progenitor star [releases a flood of neutrinos](http://hep.bu.edu/%7Esuperk/gc.html) carrying a lot of energy. This burst is detectable, and it's observed *before* the light from the actual supernova reaches the observer because it's well in advance. We observed neutrino emission from [SN 1987A](https://en.wikipedia.org/wiki/SN_1987A#Neutrino_emissions) two or three hours before its light reached Earth.
Neutrinos are fairly hard to detect, as they don't interact strongly with matter. Even from SN 1987A, we only detected a handful. To maximize your odds of detecting any of them, you'd need something like the [Supernova Early Warning System](http://en.wikipedia.org/wiki/Supernova_Early_Warning_System), a small network of neutrino detectors, all working together. It includes the [Super-Kamiokande](http://en.wikipedia.org/wiki/Super-Kamiokande) in Japan and [Ice Cube](http://en.wikipedia.org/wiki/IceCube_Neutrino_Observatory) in Antarctica.
Neutrinos [can be lethal in large doses](https://what-if.xkcd.com/73/), so these neutrinos could serve as an adequate warning sign only if you're far enough away from the supernova - otherwise, you'd just be killed! According to XKCD, you'd want to be at least a few astronomical units away to survive the neutrinos - but then, of course, the actual explosion would kill you a few hours later.
## During the event
You might be surprised to learn that asymmetric supernovae can produce gravitational waves ([Ott et al. 2003](https://arxiv.org/abs/astro-ph/0307472)). There are two possible forms of the gravitational wave signal:
1. A sharp spike followed by high-frequency oscillations, caused by a slow-rotating progenitor star.
2. Oscillating "bounces" of the amplitude caused by expansions and contractions.
Type 1 waves are expected to be stronger, but it appears that both types should be detectable by interferometers like LIGO and Virgo, assuming the sources are within the Milky Way. We're fortunate; their peak frequencies lie in the middle of the frequency range of these instruments. With peak strains of $h\sim10^{-21}$ for sources $\sim10\text{ kpc}$ away, supernovae on the other side of the galaxy could be detectable. Given that strain scales inversely with distance, the strain of waves from a closer source would be even greater.
## Days, weeks and months later
During the explosion - and in the weeks and months afterward - a supernova will emit visible light, coming from hot, radioactive bits of ejecta moving through space. Astronomers can study the [light curve](http://en.wikipedia.org/wiki/Supernova#Light_curves) of the event to glean information about the progenitor star and the nature of the explosion. Supernova light curves generally rise rapidly and then fade over time. Scientists can figure out what kind of supernova a supernova is by observing morphological properties of the light curve.
The interesting thing, of course, is that it does take some time for a supernova to reach peak brightness - maybe a few days to a couple weeks. It's *possible* that the supernova could only prove dangerous at or near that peak brightness, and so the initial increase in luminosity might be enough of a warning sign without being deadly.
[](https://i.stack.imgur.com/UmbRP.png)
Image courtesy of Wikipedia user Lithopsian.
To accurately measure the light curves from a supernova, you'll need sufficiently advanced telescopes working in a range of wavelengths. UV, infrared and visual light are your best bet, and we have many telescopes that study the universe in one or more of these wavelengths.
[Answer]
For one thing that would be the "scientific method" as to acquire knowledge and investigate phenomena based on empirical observation and measurable evidence - so to say objective rather than subjective.
Other than that, I'd strongly vote for a deep theoretical understanding of the internal workings of a star (that is **physics**) and to detect the changes in your star, obviously. **Optical instruments** (so optics and the associated technology chains of glass making, manufacturing of optical elements, e.g. grinding and polishing of lenses, as well as fine mechanical manufacturing for making your instruments). The idea of **spectroscopy** would be helpful as to measure the changes in emission wavelengths of the star with respect to its lifecycles. Measurable evidence of going supernova besides emission spectra is of course the brightness of the star - its astronomical magnitude. To measure that empirically it's advisable to have had **photography** invented (which is easier than inventing an electronic photometer).
Most of that hardware should have been available at say ~1850. Although that time lacks the understanding of fusion processes inside the star - kind of vital to the understanding of a supernova.
It's also more than noteworthy that going supernova is not exactly something that happens in no time. We're talking about hundreds of thousands if not millions of years (the heavier the star the faster it lives) from noticeable changes to supernova. That is to say: plenty of time to discover spaceflight and get the hell out of there.
[Answer]
Ghanima's answer makes the fundamental point that theoretical knowledge is required before the necessary technology is developed. HDE226868's answer is an excellent summary of the process.
There is a problem with the idea of a *home star* going supernova. A supernova event requires a considerable amount a mass. Further, a star's lifetime is determined by its mass. Here is a table summarizing the relationship between stellar mass and stellar lifetime :
Theory suggests that the minimum mass for a *small* supernova is about 1.44 solar masses. A core collapsing supernova requires 8 to 9 solar masses.
So a minimum supernova would result from a star with an expected lifespan of about 3 billion years. Consider that our sun is 4.5 billion years old, and that it has taken that long for intelligent life to evolve here on earth. This would seem to imply that a supernova would occur before intelligent life could evolve.
On the other hand, a supernova need not occur on ones home star to have catastrophic effects. Any stars and their planets in the local star group would suffer catastrophe.
] |
[Question]
[
## Premise
I am in the formation phase of a fictional world. I would like one of its notable characteristics to be extremely large waves. On Earth, most of our large waves are triggered by earthquakes, landslides and things to that effect. Here is an example from 2005:
[](https://i.stack.imgur.com/ic69e.png)
The graph makes the Earth tsunami look impressive, however this is more of an outlier. Most waves on Earth are much smaller. I would like to make my fictional world's waves to be triggered differently. Instead of sparse, infrequent natural disasters, I want something more dependable to allow for extremely large waves. This way the average wave height will be higher.
## Question
How can I maximize the wave height on my planet such that the waves average a very high number? Here I mean each wave is very large. I'm not so interested in occasional giant waves that raise the average, unless there is no other way.
Waves, indeed weather in general, are examples of highly stochastic outcomes; there is a lot of randomness and there are so many variables that come into play. This is what makes this situation very difficult but very interesting at the same time.
**Further Clarifications**
Below are clarifications to account for some of those variables. It is my no means an exhaustive list, but it's all that my knowledge base allows for, and is hopefully enough to frame the scope to be within reason.
* Desired wave height: I don't know what's a realistic expectation here, I'd like to say the higher the better
* Land/ocean ratio: configurable. I'm not sure, but I'd imagine this to be an important factor in the calculations. As a general guide, we should assume oceans account for anywhere between 25%-75% of the planet.
* Number of moons: configurable
* Planet climate: to have liquid water, it would be in the ["Goldilocks zone"](https://en.wikipedia.org/wiki/Circumstellar_habitable_zone), other details can be configured
* Air currents/streams: configurable, I know in certain circumstances, the way currents interact is one of the leading explanations for [rogue waves](https://en.wikipedia.org/wiki/Rogue_wave) here on Earth, but I'm not sure if air currents are too sporadic for my goal of consistent very high waves
[Answer]
For waves that have small heights relative to the water depth ($H\ll a$), we can use [Airy wave theory](https://en.wikipedia.org/wiki/Airy_wave_theory). This works well for waves that are far out at sea, and can include tsunamis, in deep water. I wrote about this in more detail [here](https://worldbuilding.stackexchange.com/a/73273/627), but to make a long story short, the height of a wave is given by
$$H=\sqrt{\frac{16E\_w}{\rho g}}\to H\propto\frac{1}{\sqrt{g}}$$
where $\rho$ is the density of the water and $E\_w$ is the energy imparted to it. Therefore, on a planet with lower surface gravity, the waves will, in general, be higher, as wave height is inversely proportional to $\sqrt{g}$. Honestly, the same thing should apply even with Airy wave theory isn't appropriate, because the higher the wave, the more potential energy it has, and potential energy depends on $g$. In fact, [gravity is the restoring force for all but the smallest waves](http://www.utdallas.edu/~mitterer/Oceanography/pdfs/OCEChapt09.pdf) (with frequencies of at least 10 Hz); at those tiny regimes, [surface tension](https://en.wikipedia.org/wiki/Surface_tension) is more important.
Surface gravity can be written as
$$g\propto \rho\_\oplus R\_\oplus$$
where $\rho\_\oplus$ and $R\_\oplus$ are the radius and density of the planet. Decreasing either will lead to lower surface gravities, and larger waves.
There are [some additional - local, not large-scale - climatic factors](https://oceanservice.noaa.gov/education/kits/currents/03coastal1.html) that need to be considered for wind waves (not tsunamis):
* The wind should, ideally, be moving faster than the wave. It turns out this is easier on a low-gravity planet, since for the wave speed $c$, $c\propto\sqrt{g}$. Thus, the waves will, on average, move slower, and it will be easier for wind to transfer energy to them.
* We need constant wind, moving in the same direction (rather than rapidly changing direction). [Kamino, the watery planet from *Star Wars*](http://starwars.wikia.com/wiki/Kamino), is an interesting example; rapid winds drive waves constantly. That said, the atmospheric currents there seem chaotic, which might limit wave height.
As an aside, [ScienceKeanu mentioned](https://worldbuilding.stackexchange.com/questions/115680/how-do-i-maximize-a-planets-wave-height-on-average#comment354553_115680) the large "waves" featured in [*Interstellar*](https://en.wikipedia.org/wiki/Interstellar_(film)), where a planet orbits a black hole; the gravitational pull of the black holes causes time dilation and extreme conditions on the planet. I should just point out that these aren't actually waves; rather, [they're the planet's extreme tidal bores](https://physics.stackexchange.com/a/251967/56299), which occur regularly. Furthermore, they don't change the median wave height on the planet; the true waves shown seem to be fairly normal.
[Answer]
Ocean waves (normally) [get their energy from wind](https://sos.noaa.gov/datasets/wave-heights-2012/).
Consistent, large swells on Earth come from the [trade winds](https://en.m.wikipedia.org/wiki/Trade_winds): strong winds over a long distance with consistent direction.
[](https://i.stack.imgur.com/u8vd0.jpg)
To increase those, you should have a lot of solar energy, a short day (higher rotation), thicker atmosphere and/or large east/west extents to your oceans.
[Large cyclonic storms also make waves](https://sos.noaa.gov/datasets/wave-heights-hurricane-katrina-2005/). The conditions for trade winds also help make lots of those. Because trade winds tend to only produce waves in certain areas, storm waves are important for the rest of the planet. [California surfers, for example, study them relentlessly.](http://topex.ucsd.edu/ps/Iacobellis.pdf)
[Answer]
Just two things off the top of my head:
* The lower the water density, on Earth lower densities are caused by lower salinity, the higher average wave height becomes because the water is easier to move. I understand that this is why the Black Sea and the Great Lakes are, in some ways, more dangerous to shipping than the open oceans.
* The further a "wave train" travels without being disrupted the bigger the waves can get. As waves caused by wind effect on the water surface travel under a continuous prevailing wind they build in height, obviously there is a limit but it takes a *lot* of ocean miles to get there. This is part of why the Southern Ocean is so dangerous, wind and waves can travel for thousands of miles without being interrupted and thus waves grow very large.
So a relatively freshwater ocean, oriented with a strong prevailing wind, and having few islands or other landmasses would have very high average wave heights.
[Answer]
Actually it's not that complicated: place your planet around a gas giant and make it orbit relatively close, like Io, et voilà, the gravity pull would generate monstrous waves.
The only disadvantage is that such a gravity pull would create huge internal frictions leaving the planet incredibly active with volcanic activity, probably a couple of huge eruptions a year would be usual in such environment.
[Answer]
If the planet is somewhat larger in size than Earth, and has equatorial oceans, so that the winds and waves can build up all the way around the world several times, the waves are likely to have an average height several times those on Earth.
Ash's answer says that lower water density allows for higher waves, so the water should have as low salinity as possible. If the planet has has a low density it could be larger in dimensions than Earth but have a lower surface gravity, which might compress the water in the oceans less.
I note that rubbing alcohol, corn oil, motor oil, and mineral oil are among liquids less dense than water. I also note that there are some atmospheric gases mixed in with water - sea life extracts oxygen from the water to "breathe".
Apparently there is a lot of methane gas trapped beneath the sea, and if it was released in large enough bubbles ships passing over those bubbles could lose support from the water and sink.
So possibly you could come up with a mixture of liquids and dissolved gases to dilute sea water on your planet and thus make waves bigger.
Bob Jacobsen's answer says that storms raise larger waves. And hot water makes storms stronger. So if your planet is close enough to its star,and/or the star is hotter enough than the Sun, the planet will receive a lot more heat and light hand have much bigger storm waves in its tropics. Hotter water would expand a little and be a little less dense than Earth water.
But as far as I can tell the most important way to make bigger wind driven waves on your planet is to have very large oceans going all around the planet so the winds can drive the waves around the world several times so the waves build up larger and larger. I don't know what the limit for wave size would be in that case.
I note that waves several times larger than the surrounding waves - rogue waves - are now known to be many times more common than were thought. So if someone travels to the region of that planet with the highest waves to watch them from a safe point they might perhaps see a really giant wave rising in the distance and headed toward them.
[Answer]
All of the answers so far post to the wind patterns, etc.
But those wind patterns only start the wave. The wave heights close to shore are determined by a few things already mentioned in the other answers, but also under surface geography.
Wave is moving, it has a certain amount of momentum. That momentum carries it forward, and closer to shore as the water starts getting shallower the wave rises up. Undisturbed forward momentum, combined with "climbing" the slope of the ground underwater, minus the effect of gravity pulling the peak of the wave down gives you your waves in general. Want them taller? More momentum, less disturbance of the momentum as it approaches shore, and a long slow rise from deeper water to shallow.
For details see this article on some cool mapping of the Mavericks in Half Moon Bay, California. Known for big waves (15m), famous surfing.
<https://www.newscientist.com/article/dn11667-map-reveals-secret-of-awesome-mavericks-waves/>
>
> As waves get close to shore, their base begins to run into the
> seafloor, slowing the deeper parts of the wave. The shallower part of
> the wave keeps moving at the same pace, causing the wave to stand up
> and then pitch forward. This creates the wave face that is so
> sought-after by surfers.
>
>
> Kvitek says that a long gradual slope, like the one at Mavericks,
> creates an exceptionally tall wave that holds up for some time before
> it breaks.
>
>
> And the deeper waters on both sides of Mavericks’ “ramp” allow waves
> to draw additional energy from the calmer waters on either side. “It’s
> a combination of a gradual and steady decrease in depth combined with
> a wave convergence due to the deep troughs on either side of the
> ramp,” Kvitek says.
>
>
>
You can see similar slope off the North Shore area of O'ahu Hawaii in [this (very large) picture](http://www.cartographicperspectives.org/index.php/journal/article/viewFile/859/1295/5887) .
[Answer]
Put the moon closer, or get a heavier one, so you will have a tidal wave four times a day, and probably much larger "usual" waves before and after tidal ones.
] |
[Question]
[
How can an authority verify the identity of an AI?
An easy to explain example is the equivalent of a drivers’ license.
Consider a typical situation, in the near-ish future: Police cruiser pulls over a car that has a passenger but no driver. Starts to admonish her that self-driving cars must still have a licensed driver, even on the e-lanes.
The car replies that it’s a prototype [AGI](https://en.wikipedia.org/wiki/Artificial_general_intelligence) and had the officer looked at the report when running the plate, he would see it is flagged *exceptional*. It (the car) holds a valid drivers’ license in the state.
The license is posted in the door frame, next to the weight and tire stickers.
Now, how can someone verify that the license is shown belongs to the entity in question? For normal licenses, we use photos of the face and descriptions of height and eye color, etc. But an AI will not have “biometric” attributes, and any such affordances it does posses will not have the same property of being fairly unique and unforgeable. All [Johnny Cabs](https://www.youtube.com/watch?v=xGi6j2VrL0o) look alike.
---
Note that the idea here is to verify that the system has an approved use based on its “skill” and knowledge. This is not as strong as a unique identity which you need for determining property ownership for example.
Keeping with the easy-to-understand drivers’ license, the threat model would be for some person to slap a sticker on his *ordinary* self-driving-car that has some capability for normal driving but would not understand someone directing traffic with flags or other exceptional cases.
[Answer]
# What you have, what you know, who you are
Those are the three ways that an unknown person is authenticated and authorized. For humans, "what you have" usually means a physical key or pass card. "What you know" means a password or passphrase. "Who you are" means unique biological data that is difficult to fake or duplicate, such as finger prints, retina, etc.
The digital equivalent of "who you are" is a hash. Hashes are a form of one way compression where a quantity of binary data is put through a hash function resulting in another, much shorter number. Hash functions are designed in such a way that if a single bit of that number changes, there will be large, easy to see differences in the resulting hash. There is only a one bit difference between 8 and 9. The below example shows the large differences that a single bit will bring.
```
$ echo "01234566789" > 09.txt
$ sha1sum.exe 09.txt
0230f435629ff197db2935a4f2d58d234c74de0d *09.txt
$ echo "01234566788" > 08.txt
$ sha1sum.exe 08.txt
f2408b6a33c9752882dd46aae70674f4f0597e92 *08.txt
```
The requirement for these three methods to be secure, in real life and digitally, is that they are extremely difficult to duplicate. Note also, that encryption is used for verification as well as concealment. In this case, encryption will be used to ensure that the AI gestalt installed in the car is authorized to be there.
## What the car has
The car has a stamped nameplate with a barcode/QR code of its serial number and certificate of authenticity. The certificate of authenticity contains two thumbprint hashes of the AI's gestalt; one by the manufacturer and one by the certifying authority. It also has a QR code of that AI's public key. In addition, the car will have a [FIPS 140-3](https://en.wikipedia.org/wiki/FIPS_140-2#Level_3) cryptographic module for generating hashes of itself and responding to authentication claims. This crypto module will work much the same way as the chip in your debit card. Of necessity, this physical protection must extend to whatever hardware the AI is running on in the car.
## What the cops/inspectors have
The cops have a big list of authorized AI gestalts hashes and associated public keys. They have the public keys associated with the private keys that signed the AI gestalts. With the hashes and public keys, they have everything they need to cryptographically verify that the AI gestalt is "who it says it is".
## What the certifying authority has
They have a copy of the gestalt (though not the source code that created the gestalt), the manufacturer's hash of the gestalt and manufacturers public keys. They do not get the private keys because that only leads to shenanigans (which this whole complicated expensive process is trying to avoid).
When the certifying authority creates their hash for the gestalt, they will add a [salt](https://en.wikipedia.org/wiki/Salt_(cryptography)) to the gestalt before hashing. Salting the gestalt before hashing ensures that the gestalt is different from the manufacturer's hash ('cause it doesn't make much sense if the two hashes are the same). Salting also makes it much harder for attackers to recover the certifying authorities private key because to recover the key would require recovering the salt as well as the private key. This is much much harder.
Spot check that the cars crypto module and AI brain are FIPS 140-3 compliant.
## What manufacturer has
The car/AI manufacturer has the private key that they use to sign the AI gestalt before installing it in cars. They also produce a hash of the gestalt. Manufacturers go through the same process of salting and hashing the gestalt that the certifying authority does.
They also make sure that the crypto module and AI brains actually are FIPS 140-3 compliant. For each crypto module, they install a new private key.
# Buzzword Compliance: Blockchain
As much as I despise buzzwords and handwaving "it'll do magic" tech, there is a valid use case for blockchain tech in this instance. Consider that blockchains are really just big distributed ledgers shared by people who really don't trust each other.
In this case, a blockchain would be built to hold the car specific public keys, the manufacturer and certifying authority public keys, and hashes of certified gestalts. The blockchain becomes the canonical record of who did what and when. This prevents attacks where someone attempts to change a public key sneakily. They can't since the record is immutable. Well, they can change it but that will require enough resources to get a majority on the blockchain. Such a majority *will* be noticed.
As each new gestalt is published then certified, all the appropriate information about that gestalt is added to the blockchain. Once added, it's permanent.
## Authorization Verification Process
This is how things might go
1. The cop will scan the name plate of the car for manufacturer, model, manufacturer AI gestalt hash and certifying authority AI gestalt hash.
2. The scanner looks up the manufacturer, model and both hashes against the known-good configurations. If all four data points match, then the AI in the car is probably good to go. This is the weakest but fastest verification of the car's AI.
3. For stronger verification, the cop will plug in the scanner to a data port on the car. Once connected, the car will respond to a command to encrypt some long really long and randomly generated number with the AI's private key. Since the scanner also has the public key associated with this car, if the crypto module returns a strong that can decrypted with the public key then the cop/scanner knows that the crypto module is genuine. This verification process prevents an attacker from stealing the correct response from authorized hardware and just replaying it back to the scanner. This, in addition to previous verification steps.
4. The strongest verification will be to take the car into a shop and examine the crypto module. Since it's FIPS 140-3 compliant, any tampering will be evident and the car will fail inspection. This, in addition to all the previous verification steps.
## Weaknesses
Since everyone messes up and even strong security systems eventually are compromised, as described, this system does not account for the need for rapid change of public-private keys should they be compromised. Say, someone at the manufacturer or certifying authority fat fingers which key to add to the block chain and they add the private key when it should have been the public key.
There are a thousand ways to break this system and it will take a lot of very careful planning in order to make it very hard, even for nation-states to compromise it. (Ha! Well, that's far far beyond the original threat model but this was fun to write.)
## Modern Web Cryptography
Much of the process and crypto primitives described above can also be found in modern web crypto. If you see an 'https' then your browser is using a system of public and private keys to authenticate and authorize the server you're connecting to.
## Not yet covered areas
What this process doesn't cover is the data that the AI uses to navigate with. Where that comes from and how it's used is outside the scope of this question.
Attacks on this data would preserve the integrity of the AI but cause errant behavior.
[Answer]
This can be done in a similar manner as we check the authenticity of software today - using license keys and checksums. This way we can be sure that:
* The program in question is legitimate, particularly if license is registered in central database;
* The program in question was unmodified, at least to the point of its installation;
However, there are no easy ways to check if the program has been hacked. If the program in question is a "learning" AI, then every installation of it would be different, and while we can still say that the program initially was exactly what we wanted it to be, there is would be no way of telling how this program changed from that moment and whether those changes were legitimate.
If the program in question is a "static" AI, then situation is more manageable. The difficulty of this task will be comparable to checking if a particular iPhone is not lost/stolen and it had not been jailbroken.
[Answer]
Track the transfers of entity from vehicle to vehicle, then use the vehicle identification.
What you’re trying to do is authenticate the ‘mind’ of the vehicle to make sure that it’s allowed to drive. Assuming that the AI’s might happily share licence information with each other and are too complex to perform a checksum or program integrity check on the only way you can authenticate the mind is via the body, in this case the vehicle.
So: only licenced engineers are allowed to transfer AIs, whenever they do they *must* log the new location of the AI. At that point verification becomes a matter of physical authentication which can be done many different ways.
On a more abstract bent: what you’re aiming to do seems a bit pointless. If you’re authenticating that the AI knows how to drive you can essentially perform a roadside ‘driving test’ to check that the vehicle will respond appropriately to a set of standardised tests. The AI should be able to do the test very rapidly if appropriately designed. It doesn’t matter if it is the AI that you think it is if it knows how to do the thing you want it to do. If one of the questions is designed to weed out the prototype ‘trusted’ cars from the non trusted ones then the non trusted ones will fail the test. If the non trusted ones pass the tests then they are, to all intents and purposes, trusted.
[Answer]
# You cannot do it, unless you make some assumptions
Making the full proof cannot be done here, because it requires a university level course in Information Theory, so I will just state it as bare fact:
**You cannot reliable authenticate a piece of software when someone else is in control of the hardware it resides on**
This is — for instance — why we cannot have cheat-proof computer games. So unless you make certain assumptions, the answer to your question is:
**That which you ask for cannot be achieved**
And for the record: the same goes for bio-metric identification of humans. Unless you make **some** assumptions, then you cannot authenticate a human against their driver's license with 100.000% certainty. Instead you must make some assumptions, such as "Human fingerprints are unique and can always be distinguished from each other".
## The assumptions when it comes to AI
The assumptions you have to make in your case is:
* A piece of hardware that has been validated by the enforcement agency (i.e. Police/Highway Patrol) can make an accurate memory dump of the AI in question, being given the code, the whole code and nothing but the code.
* The AI cannot be reprogrammed / replaced.
If this is the case, then it is actually quite easy. The officer will make a dump of the AI's software and the officer's hardware unit will make one or several [**hashes**](https://en.wikipedia.org/wiki/Hash_function) of it. These hashes act as fingerprints of the AI. In fact they can even work as the **identity** of the AI.
All the officer then needs to do it make a lookup and verify that the AI with these hashes is authorized to travel in / drive that kind of vehicle, in that area, on those types of roads, under those conditions, and so on.
Alternatively the AI comes with an public authority issued [**digital certificate**](https://en.wikipedia.org/wiki/Public_key_certificate) that lists all the rights of the AI. The certificate will certify that the AI with the hashes specified has the following enumerated rights. The officer's hardware needs then only verify the certificate, which is a mundane affair.
This then comes with an additional assumption:
* Digital certificates cannot be forged
The weakness is of course that 2 out of 3 of those assumptions are fairly flimsy. There is nothing to say for instance that the original AI was not disconnected from the actuators of the car, and another AI installed in parallel with this one that does the actual driving. But when the officer connects their scanner to the car, it is the original AI that responds.
There is no way around that unless the **government** has a monopoly on building AI cars and has 100% control over the hardware. And even then you have the issue that no-one will ever have 100% control over the hardware...
[Answer]
I'm not a security expert, but I think you can do most of this with simple private key/public key encryption. You just need to establish the correct protocols so everything can be verified, and trust the private keys remain private. So it's not infallible, but then again nothing is.
The car and cop need to be able to generate encrypted signed messages meant for the car's manufacturer, meaning no one else can decrypt the messages and they are verified as being to-and-from either the car and the manufacturer or the cop and the manufacturer.
The cop generates a random token and it sends an ID request to the manufacturer for this car's stated name. At the same time, the car uses the random token and sends it's authorization to be verified to this officer. You could do it other ways, but this way means the officer and the car both have to consent to being verified.
Since the cop is getting verified too the cop also sends the token to the main police authorization service (we'll call it Big Blue). This step isn't necessary. I just like it this way so not just anyone can verify a car.
The manufacturer decrypts both messages. The car says "Hello manufacturer X, it's me Bob, please verify with officer Pebbles Larue (token)", then it gets a message from the cop and says "This is officer Pebbles Larue, please tell me if this is Bob or not (token)," then the token gets sent to Big Blue and Big Blue says officer Pebbles is on the up and up, so the manufacturer responds to Pebbles with a thumbs up emoji, meaning this is indeed Bob.
[Answer]
Assumptions:
* The AI is a true AI, and has operational control of its hardware.
* It has some form of memory that is write once. This part of the memory is not accessible without destroying the machine.
Now: Part of that read only memory is the private key for Hal's private public key encryption. The AI is the only place in the world where this key is written down. To get this to be true, the AI has to be able to generate the key pair on it's own (trivial for a computer) and register the public key in a key repository.
So proof of identity works like this:
COP: Who are you
HAL: I'm Hal 2764. I'm registered. I'm listening on redtooth 7
The cop's computer takes today's date, a random string token, and it's own identity, and encrypts this using Hal's public key, and sends this string of stuff to Hal on redtooth 7.
Hal decrypts this using his private key. ONLY someone with the private key can do this in reasonable time. Hal then looks up the public key of matching the cop's computer's identity, re-encrypts the token, along with the latest date/time stamp, and some random noise, and sends this back.
The cop's computer decrypts this data using its private key. The tokens match, proving that Hal was able to decrypt the packet, and hence actually has Hal's private key.
More about public/private keys <https://en.wikipedia.org/wiki/Public-key_cryptography>
[Answer]
Not feasible.
All methods proposed are fundamentally flawed.
You can, up to a point, certify hardware.
Some hardware include some "write-once" memories very difficult to "spoof".
You can also "homologate" procedural software using signed signatures and be reasonably sure what's actually running in the hardware hasn't been tampered with.
Unfortunately nothing of this is applicable to a reasonably complex A.I.
Actual knowledge in a modern A.I. resides in data, this may be the weights defining a Simulated Neural Network or some Content Database or something yet different, but, in all cases, dynamic in nature and thus defying some simple(?) signing scheme.
Normal I.D. cards rely on fact "hardware" is rigidly connected with "software" and there's *no* way, at least in the foreseeable future, to "reboot" some Natural Neural Network with a different "Operating System".
The fact "Software" is not tightly linked to underlying hardware (and *many* layers ensure a program doesn't even know on which platform it is running, at least in many modern Programming Languages) is a game-changer.
You can easily "clone" a program and have it run on many different hardware platforms; Should all of them have the same "I.D." card?
Even if they started "identical" thy are bound to have different "experiences" and thus diverge, possibly in radical ways; At which point your "ID." should be invalidated?
No. The only potentially viable approach is Python's [Duck Typing](https://en.wikipedia.org/wiki/Duck_typing). Prepare specific tests (they can be administered quite fast due to electronic speed) to test if a certain program can (still) perform a certain task.
In the specific case this is equivalent to have the "policeman" connect some testing device to A.I. and have it pass a full fledged driving license exam. *No* other test would provide any reasonable answer.
Note these problems are similar to what happens with on-line identification which is much less reliable then many people think (as the many "identity theft" cases testify) and essentially works well (when it works) by providing feedback to user about all transactions, so that they can be traced and stopped, not by preventing abuse.
[Answer]
It's not really a problem.
An AI will (presently) never attain a valid driver's license because the law simply doesn't allow for it. That means that every car driving mostly (or even fully) autonomically must have some sort of exception which, due to the associated cost, is valid for the car model (not an individual car), and only valid with some other contraints (such as a human driver with a valid license who is finally to be blamed if the AI drives into a truck). A prototype, likewise, would have an exception, but could never get a proper license.
Unluckily, at some point in the hopefully very distant future, there *will be* a desire for AIs to have proper driver licenses. When that happens, it is up to the legislative to come up with a solution.
The identity problem could be solved with readily available cryptographic algorithms. A simple digital signature would do just fine. This could come from the drivers license office if you like, but the maunfacturer could as well do it as long as their signing key is either registered in a central database or properly signed certificates in a state-controlled hierarchy are supplied (much like in every web browser nowadays, except now it's more a wild west hierarchy).
Or, seeing how it's well known as a trope that AIs are not allowed to lie, you could simply ask the AI for its identity and trust it.
Realistically, you know what will happen. Legislative always goes the most stupid, most sure-to-fail, and most needlessly expensive way.
Which means cars with AIs entitled a driver's license will either simply have magenta-colored license plates (not to be confused with fuchsia-colored plates which require a human driver with a license), or you will have a sticker in the front window, and you will not be allowed to change plates or remove the sticker. The sticker will cost you approximately 500 dollars per year, and you will need an additional sticker (valid for 8 months) if your AI is qualified to drive through a tunnel.
] |
[Question]
[
A friend and I are creating a magical bird that eats gemstones then uses them to form a thin coat of crystal armor over its body. Is there any way for this bird (or any living thing) to actually have crystals growing on its body? I kind of want this ability to make scientific sense, but explanations that involve magic are okay too.
[Answer]
# It's known as [Biomineralization](https://www.hindawi.com/journals/scientifica/2012/867562/)
>
> Biomineralization is the formation of complexes containing inorganic
> materials by living organisms. This occurs in organs as diverse as
> bone, teeth, egg shells, and invertebrate exoskeletons. Calcium is
> a very “popular” biomineral, occurring for example, as phosphates in
> vertebrate skeletons and carbonates in mollusk shells. However,
> another important player is silicon. Silicon is the second most common
> element in the Earth’s crust after oxygen, and silica (silicon
> dioxide) is the most abundant compound in the earth’s crust.
> Biosilicification is the process by which inorganic silicon is
> incorporated into living organisms as silica, which occurs on the
> scale of gigatons. In practice this involves the condensation of
> orthosilicate Si(OH)4 into long polymers with the elimination of
> water.
>
>
>
In the case of stinging nettles, the stings are made of hollow [silica](https://en.wikipedia.org/wiki/Silicon_dioxide) spears containing formic acid:
[](https://i.stack.imgur.com/ZWmN0.jpg)
*Attribution Wikipedia CCL. 2019.*
[Diatoms](https://en.wikipedia.org/wiki/Diatom) (microscopic animals) make their own armour out of it:
[](https://i.stack.imgur.com/9aCA3.jpg)
*Attribution Unknown 2019*
In principle if your organisms were to make their armour from - instead of silicon dioxide - say aluminium oxide, then they would have a Saphire or Ruby armour, or with Beryllium compounded, Emerald. The colour/shade and luster would vary perhaps depending on the particular minerals available in the diet of your creatures.
The [Placoid scales](https://en.wikipedia.org/wiki/Fish_scale#Placoid_scales) of sharks (AKA dermal denticles) are made exactly like teeth, with a blood supply, [dentene](https://en.wikipedia.org/wiki/Dentin) ([hydroxylapetite](https://en.wikipedia.org/wiki/Hydroxyapatite)), and hard enamel on the outside, acting to reduce drag, they're also very tough and have enabled shark species to survive for millions of years without changing:
[](https://i.stack.imgur.com/bgC74.jpg)
*Attribution Wikipedia CCL. 2019.*
So, yes, it's possible, because it's already here. Adapt it to your needs as you see fit.
[Answer]
Yes, but it would come with problems.
Disclaimer: I'm not a biologist.
There are a number of chemical solutions that can be used to "grow" crystals. It's even possible with nothing but salt and water, given good temperature control and environmental conditions. You could potentially accomplish that with something like sweat glands. Other types of crystal may require more exotic biological systems, but I don't see why they couldn't work in the right environment.
**Problems**:
Weight - crystal armor is going to be either fragile or heavy. On Earth, a bird would have a hard time flying with enough crystal of sufficient "toughness" to act as a good defense against predators.
Flexibility - Hard crystal is going to be solid, so it would have to either grow in many small pieces (more fragile, with more vulnerabilities) or in immobile "plates" that would make flexibility a challenge. (Like turtle shells)
Temperature control - sweat will be less effective at cooling the body, if it works at all. (depends on how much of the body is covered in crystal) The exact material of the crystal will determine how good of a conductor of heat it is, but it could either over-insulate the creature, or be overly-effective at dissipating it's body heat. The creature will need to account for that, one way or the other.
I'm sure there are other potential complications, but that's all that comes to mind for me.
[Answer]
You can even grow crystals yourself: When you sweat, your body basically releases salt water on your skin. Once the water dries off, you are left with salt crystals. They are of course rather tiny and not exactly like an armor.
[Answer]
Crytals can grow on many things. you can do a crystal growing experiment and the crystals could grow on plants.im not sure if it's ever been tried before. you can try this with these links:
<https://kitchenpantryscientist.com/crystalline-entities-growing-alum-crystals/>
for crystals to grow in general:
Crystals often form in nature when liquids cool and start to harden. Certain molecules in the liquid gather together as they attempt to become stable. They do this in a uniform and repeating pattern that forms the crystal. In nature, crystals can form when liquid rock, called magma, cools.
It is possible for crystals to grow on living organisms in the right conditions
[Answer]
Yes, and if you drink enough Port to give yourself Gout then you can try it for yourself.
>
> The symptoms of gout are due to the formation of uric acid crystals in the joints and the body's response to them.
>
>
>
[All you wanted to know about Gout.](https://www.medicalnewstoday.com/articles/144827.php)
[Answer]
The problem is, this is a bird. And if it flies, crystal shell is not the best, or even a plausable option.
**Fancy beak**
Crystal is heavy, not so flexible, brittle, and offers very little compared to that for a bird. One thing I can think of is a crystal beak.
Different feeding habits require different biological bodies. Maybe your bird eats minerals and breaks down different minerals, makes a coated crystal beak. So the beak is hard enough, durable enough, and can be used to eat more mineral.
Make sure your bird stores minerals and changes beaks like a snake shedding its skin, and we are good to go. Add talons to the equation and a bird with crystal beak and talons is here now. Fancy.
**Crystal feathers!**
Alternative is, aerodymanic crystal structure.
Crystal feathers! Yey! The bird will have thin crystal feathers arranged in a strategic way to maximize the flexibility and reduce the weight, create aerodynamy to help it fly fast.
**Diamond trex?**
Remember the first sentence? Yeah, things change for an ostrich. Or any bird prefer running really. An ostritch can afford to be heavier and can access to more ground resources if it does not need to fly.
Maybe a heavier, bulkier ostrich that relies more on muscles instead of dexterity can eat crystals and grow a magnificent crystal tail. Like a porcubine. Or a hedgehog. Kinda like a spiky dinasaour, running to their prey, stabbing them with lots of crystal needles, and knocking them over with weight and strength. An interlocking crystal plate armor around the bird can offer protection, can be used as a weapon and armor and a hunting method.
Make it tameble like a horse, and you can even add crystal armored knights riding crystal covered birds. Beautiful. Deadly.
There are crabs with solid shell, sea snails with mineral made shells, and there is a snail growing an iron armor around it. So, if you consider iron crystals good enough, there is a living animal doing exactly this already. Check it out. <https://en.wikipedia.org/wiki/Scaly-foot_gastropod>
] |
[Question]
[
I recently finished reading the Kim Stanley Robinson novel *2312* - set, of course, in the year 2312. Part of the background to the political negotiations and ongoing terraforming in the outer Solar System involves the transfer of energy to Titan, one of Saturn's moons, from the Vulcanoids, a population of asteroids orbiting the Sun. As far as I can tell, this involves focusing light from the Sun on the asteroids into fine beams, which are then transmitted to Titan with high precision. The energy then warms the moon, and plays a role in the ongoing terraformation.
Speculating on the fine details of realistic technology three centuries in the future is maybe too much even for Worldbuilding Stack Exchange, but I'd like the know some of the main hurdles engineers would have to overcome to do this, even starting in the present day.
What are the physical challenges involved in sending beams of light to Titan, and how could they be overcome, using technology from today or perhaps in the near future (the coming decades)? I know that [laser attenuation](https://worldbuilding.stackexchange.com/q/32549/627) is going to be troublesome, but are there any other issues, and can they be combated?
---
As an addendum, I'd certainly enjoy seeing [hard-science](/questions/tagged/hard-science "show questions tagged 'hard-science'") answers, but they are absolutely not mandatory (hence, the absence of the tag). MichaelK has written [an excellent](https://worldbuilding.stackexchange.com/a/67691/627) non-hard-science answer that answers the question well, and I'd love to see others like it. However, there may be bonus points for anyone who takes the [hard-science](/questions/tagged/hard-science "show questions tagged 'hard-science'") plunge.
[Answer]
# The problem is that "focused" does not really mean "concentrated"
Everyone that has ever played with a magnifying glass "know" that you can take the light from the Sun and turn it into an infinitely concentrated dot. This is in essence a variant what you are trying to do.
The problem here is two things:
1. The only reason you can get a dot that small is because the magnifying glass is very close to the "target", compared to the distance to the light source.
2. That is not actually an infinitely concentrated dot; it is a focused image of the Sun.
[](https://i.stack.imgur.com/VPrpm.jpg)
*That is not a very small dot of light, that is an image of the Sun. ([Image source](http://miraimages.photoshelter.com/image/I0000m_8IKJlVsQY))*
It turns out that you cannot gather up light and make it go in a beam that is more narrow leaving your light gathering device than it was when it came in. The light beam will always be at least as wide, or wider. To explain this in full detail requires a university course in optics, but in short the principle is called [**The Conservation of Étendue**](https://en.wikipedia.org/wiki/Etendue), and if you want some really hard science I encourage you to read on that link. But it is way too advanced — and it will not serve anyone's purpose — to quote that in full here.
So you will forgive me if I focus the answer a bit. Or rather: concentrate it. ;) And if the answer below seems boring or hard to grasp, I recommend [xkcd: what if #145](https://what-if.xkcd.com/145/).
When you use optics to move light from a light source, and project it somewhere else, the **smallest** you can make the projected light is when you attain an image of the light source that is in perfect focus. "In focus" in this case does not mean "concentrated to a very small spot", but instead means that you can see every detail of the light source clearly, because it is not blurred. Simple rules of optics dictate that you can not make the projected light any smaller than this.
The next rule of optics say that the perfect way to project a light source some place else is the [pinhole "lens"](https://en.wikipedia.org/wiki/Pinhole_camera). With a pinhole you will always attain a perfectly focused projection, so with a pinhole, you will always attain the smallest projection.
The next rule of optics say that an infinitely small and perfectly flat mirror is like a pinhole, only that it has the added benefit of being able to bounce the projected image in some other direction.
Yet another rule of optics says that every lens — like the magnifying glass above or in the case of the question: your sun beam device — can be approximated by assuming it consists of an infinite number of infinitely small mirrors. The projection from the lens is just all of these images from the mirrors overlaid on each other.
Now comes the kicker:
The size of a perfectly focused image, using a pinhole, is proportional to the original in the same way that the distance between the lens and the image, and the lens and the light source is proportional to each other.
[](https://i.stack.imgur.com/8HFv0.png)
If you divide the size of the image with the size of the original, you get a ratio... say 1 to 10, the image is 10 times smaller.
That ratio is the same as between the distance from the hole to the image, and the distance from the hole to the original. So if the camera is 1 meter deep, then the distance to the tree is 10 meters.
For your project this means that this "lens" of yours — and I say again: all lenses, optics and other such devices can be approximated by an infinite numbers of mirrors, that in turn are like pinholes — must be closer to Titan than to the Sun. Otherwise the projected image of the Sun on Titan will be **larger** than the Sun itself and therefore weaker in intensity; you gain as near to nothing it makes no odds.
Assuming you want this focusing device of yours to not waste any sunlight by making it fall **outside** of Titan, the image of the Sun must be smaller than Titan itself. And since the ratio between the size of the Sun and the size of Titan is about 279 : 1, it will not really make any sense to use this scheme of yours until you have gotten your concentrating device so close to Titan that the distance from this device to Titan, divided by the distance from the device to the Sun, is 1 over 279...
... i.e. you are nearly there anyway.
You might as well then put your reflectors in orbit around Titan and harvest the sunlight there. This also means that you do not need to spread it all over Titan but can put it in spots of greater importance.
[Answer]
# There are vibration based minimum size limits
Summary: If you are using either a laser or some other focusing mechanism, there is a minimum size limit to such a device, below which it will not be able to accurately deliver its energy at great distances due to vibration.
Assertion: A laser mounted on ISS could not accurately hit an object the size of Titan at the distance from the Vulcanoids to Saturn due to the vibration of ISS.
# Vibration measurements
For the International Space Station, we can get estimated vibration from Figure 1 of [this paper](https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20000034094.pdf). Vibration is graphed as frequency in hertz versus acceleration in root mean square micro-g's.
Vibration can be modeled with simple spring dynamics, so that the position of a sinusoidally moving spring is give by $$x(t) = A\sin(2\pi f t)$$ where A is amplitude, f is frequency and t is time. We are given root mean square acceleration, and we wish to find amplitude. Acceleration is the second time derivative of position $$a(t) = -A(2\pi f)^2\sin(2\pi f t)$$ and the root means square acceleration is the magnitude of the acceleration sine function over the square root of 2, expressed as $$a\_{rms} = \frac{A (2\pi f)^2}{\sqrt{2}}.$$ We can solve this last equation for $A$ in terms of $a\_{rms}$ and $f$, both given to us in Figure 1. I measured the various points on that figure, and got a maximum vibration amplitude of about 4 mm at about 1 Hz.
# Projecting this vibration to Titan
Using basic trigonometry (right triangles, basically), we can determine the effects of this vibration on a distant target. If a laser pointer of length $l$ were vibrating at 4mm, and it were pointed at an object of radius $r$ at a distance of $d$ away, vibrations would cause the object to be missed entirely if $$\frac{4\text{mm}}{l} \gt \frac{r}{d}.$$
Since we are dealing with Titan, we can use the radius of Titan as $r = 2576000 \text{ m}$ and the distance between the Vulcanoids and Titan, about $d = 1.346e12\text{ m}$ at minimum (roughly 10% more at maximum). Plugging in $r$ and $d$ with our given 4 mm of vibration, we find that our laser pointer must be about 2 km long for the amplitude of the vibrations to be less than the radius of our target.
Alternately, we can say that if the focus were 100 m long, roughly the length of the ISS, then the maximum allowed amplitude of vibrations in the ISS would be 0.2 mm. Either way, it is clear that ISS is too small and vibrates too much to reliably hit Titan at 9 AU distance.
# Mitigating factors
Since it is left open-ended in the question what the actual mechanism of power delivery over this great distance is, these vibration limits answer the question of "what are the main problems."
The first and most obvious mitigating factor is to simply make the focusing mechanism very large. If the focusing mechanism were built into one of the Vulcanoid asteroids, that would help alot.
The second obvious mitigating factor is to create vibration buffering mounts for any heavy equipment in the station. Modern industrial equipment is tuned to be remarkably vibration free: the [GE LM2500](https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=4&ved=0ahUKEwiez_OIr73RAhVUOFAKHa-aD4wQFggwMAM&url=http%3A%2F%2Fasmedigitalcollection.asme.org%2Fdata%2FConferences%2FASMEP%2F82292%2FV002T03A013-95-GT-373.pdf%3FresultClick%3D1&usg=AFQjCNF0UvqgcnFZRpmZ74ZEbfMSNzujBQ&sig2=XWUmbX7lOooZydpUC3zg5g&cad=rja) marine gas turbine engine alarms at 0.1 mm vibration amplitude; [Wartsila's W20](https://publications.theseus.fi/bitstream/handle/10024/104065/Orn_Johannes.pdf?sequence=1) (20 cylinder) marine diesel generates about 0.25mm vibration on the block during normal operations.
Still, even with very low vibration levels, the inaccuracy of the beam at such a distance is notable. If the projection of vibration on the target is a significant percentage of the target's radius, the delivery system may not be adequate for the purposes of whoever is paying to have this energy delivered.
Sunlight delivered this way, for example, wouldn't be very useful for growing plants. Lasers aimed at a power station on Titan wouldn't be of much use either. The magnitude of the vibration problem depends a lot on the uses of the delivered energy.
[Answer]
There is a fairly brute force means of achieving these ends, and you can "handwave" a bit to say Robinson is describing parts of this device.
What you want is an [Artificial Laser Star](http://laserstars.org/amateur/scifi.html). Using the ionized plasma of the solar photosphere as the lasing medium, it is possible to build laser emitters of immense power and beam energy to Saturn (or well out into the Oort cloud, for that matter). Indeed, something like this could be used to launch laser lightsail driven starships much like Robert L Forward suggested.
One version of the Artificial Laser Star involves a series of mirrors orbiting the sun. A laser is fired into the platoon and bounces around the sun in a ring between the mirrors. As the ring passes through the ionized plasma of the photosphere, a population inversion occurs and more laser light is generated, with the ring acting as the "cavity" of the laser and the mirrors as the resonating mirrors. When the beam is of the appropriate power, one of more of the mirrors is "half silvered" (probably by manipulating the reflective index of the material) and the beam is emitted into space.
Now the biggest issue here isn't creating the beam or using "Vulcanoids" as the mounts for the mirrors and control devices, but rather how to keep a continuing beam aimed at Saturn (or more specifically, Titan). In order to do this and prevent incinerating spaceships and planets which might pass through the beam path, the beam should be emitted above the plane of the ecliptic, and at one or more mirrors in highly eliptic orbits around the sun. These mirrors then redirect the beam back to another series of mirrors (probably in polar orbit around Saturn), which then direct he beam onto Titan. Fresnel lenses or diffraction gratings could be used as substitutes for mirrors, if desired.
The other advantage of this system is the beam can actually be allowed to diverge, since it can be refocused by the relay mirrors or lenses between the Sun and Saturn.
[Answer]
Focusing light this way is not really the way light works, as the nice answer by MichaelK describes. However, simply focusing the Sun's light is a sortof-naïve thing to do anyway. Making enormous mirrors or especially lenses is difficult, and visible light suffers some diffraction-related issues. Hence:
# The engineering and Physics problems are greatly reduced if, should you want to "beam" something, you make the beam yourself.
Specifically, I suggest gathering energy, and then using it to pump a high-frequency laser. This can be done with solar panels (in orbit, or on an asteroid (which you would have to move into place)). Near the Sun, panels can pick up more energy, but heat is a major problem. Perhaps a thermocouple from e.g. Mercury's surface to its interior would work better.
On the Titan side, you scoop up most of the laser's energy and use it. An IR laser would be easier to generate, but a gamma-ray laser carries more energy and also would have less diffraction. Happily, since Titan has a thick atmosphere, vacuum frequency lasers can be used to heat the atmosphere directly.
---
But the whole idea of interplanetary-scale beamed power is sortof impractical overall. In 300 years, optimistically we have fusion, and Saturn is a rich source of fusible isotopes with a relatively shallow gravity well.
Also, since Titan is *almost literally made* out of rocket fuel, blasting it into a nearer Solar orbit (catalyze Oxygen compounds out of the rocks) might be easier.
Finally, if you don't care about [hard-science](/questions/tagged/hard-science "show questions tagged 'hard-science'"), then you can play silly games like opening a wormhole from low-solar orbit to high-Titan orbit.
[Answer]
Light is already beamed to Saturn from the sun, however for it to have any consequences different to the usual (bit of light and heat) then you would need to separate an individual member from the spectrum of light. Essentially I'm talking about a laser. Unfortunately a focused beam of light from the sun can not have any obstruction. Fortunately space is mostly an empty void and this is unlikely to happen. However in the case of a moon orbiting Saturn it is likely that the moon will be eclipsed by its host most of the time. That is a huge problem. Another issue is that focusing light across such a long distance is incredibly hard as light disperse over distance. My only modern solution would essentially be an extremely long fibre optic cable. Lastly it will be have a very small difference on the heating effect of the whole moon but instead on a very small single point.
I hope this helps.
] |
[Question]
[
I have a town that I'm designing (in a D&D campaign, think Neverwinter in terms of technology) that I want to be a town on a river/lake/ocean/whatever. I would like for this town to be unique from other towns in the ways that they have figured out how to wield the power of water. I know that we have things like the Hoover dam that provide power for a lot of people, but what would the logistics of such a town be? Could they survive? Could they thrive? Would there be a population limit, or any limits at all?
[Answer]
Since you state that this is a D&D campaign, I would have to imagine that magic would be available in the construction of a dam, which I would see as the most logical way of getting power from water. Hoover Dam, which you mention, generates a tremendous amount of electricity every year (wikipedia page lists it as 4.2 billion kWh per year). Putting this in perspective, that is enough to supply (if my math is correct) the entire state of Colorado with electricity. I'm using the Wikipedia page on the Hoover Dam and the information at [eia.gov](http://www.eia.gov/state/?sid=CO#tabs-4) for Colorado electricity usage and their sources. What I think would be more interesting is the use of the dam for more than just energy production. The structure could be used as the city itself, which would lend to defense as long as the dam is made from similar materials as Hoover Dam is.
I would also see a large part of the food for the city to come from aquaculture. You have a giant lake so you might as well use it. Something to consider is the amount of area now submerged that would have been above water originally. Hoover Dam flooded enough area that small earthquakes were detected as the area filled with water.
Depending on the surrounding area, your dam city could end up being targeted for conquest simply because it has a large reservoir of water available, especially if it is freshwater. I have no idea how salt water would or could be handled differently.
Now, time for the elephant in this room. You mention Neverwinter as a source of technological inspiration. I've never spent much time in the realm of Forgotten Realms, but I don't think Neverwinter had electrical generation. If it did, I would assume it would be more along the lines of a coal plant or similar. Could someone create hydroelectric power? Sure, as this snippet from the [Department of Energy](http://energy.gov/eere/water/history-hydropower) covers:
>
> During the 1700s and 1800s, water turbine development continued. In 1880, a brush arc light dynamo driven by a water turbine was used to provide theatre and storefront lighting in Grand Rapids, Michigan; and in 1881, a brush dynamo connected to a turbine in a flour mill provided street lighting at Niagara Falls, New York. These two projects used direct-current technology.
>
>
>
So to get to the specific questions raised:
1. Logistics - The logistics would be extremely complicated, even by today's standards. Could it be done? Yes, but you'd better have a real genius running things. Maintenance would also be a potential nightmare.
2. Survivability - Unless there is a catastrophic failure, it would be quite survivable. If you were to have a catastrophic failure, I'd imagine something along the lines of [the Yellow River flood of 1887](http://en.wikipedia.org/wiki/1887_Yellow_River_flood).
3. Thrivability(is this a word?) - Don't see why not. Fresh water is usually the hard thing to come by for civilizations. As long as an Evil Bad Person didn't contaminate the reservoir, I don't see much that would impact it.
4. Population Limits - As I said above, the state of Colorado's electricity needs match what Hoover Dam produces. Colorado has a population of around 5.3 million according to Google, so I think a fantasy medieval setting would hit other limits such as just how much food is available.
I hope this provides some food for thought.
[Answer]
If the water has enough pressure (large dam, coming from great height, or naturally coming at high pressure out of earth (possibly due to volcanic activities) and you can maintain that pressure over a larger pipe system, you can use the water for power almost like you can do electricity. Instead of electric motors, you'd use water turbines (a town that has water as main energy source would almost certainly optimized the water wheel into a water turbine), or for limited movements, use the water pressure directly in the manner of hydraulics. Instead of electric switches, you'd use valves.
Modern plumbing (running water in every room, water toilets, central heating — even though the actual heating might still happen with wood) would be known and used in that town. On the other hand, houses may also be cooled in the summer by simply having some water running over their roofs/along their walls. And probably there would also be sophisticated fire-extinguishing systems using water.
Water, if available in sufficient quantity, can also effectively be used for defense, beyond the usual moat. For example, have big valves besides your town gates, which allow to simply sweep away the enemy. If cannons are already known in your world, a directed water jet can make a cannon temporarily unusable (wet powder isn't useful for shooting).
And of course the town would be full of water-based pleasure installations like fountains. Swimming pools would be common, both public and private ones. Possibly some houses would even have lifts, which could basically be cabins swimming on a lock like those used for ships. A major attraction could be a water-powered pipe organ which, unlike other pipe organs, needs not be powered by humans, and thanks to the power of the water has the loudest sound of all organs known in your world. That organ might also be used for practical purposes, for example for everything church bells have traditionally been used.
And if you want something really advanced, you can even make a water-driven computer. It would of course not be as powerful as our computers, but probably would we on parity with the earliest computers in our history.
[Answer]
It depends on what kind of water source they have. If it is a large slow delta like the end of the Amazon or Mississippi, then there isn't a whole lot you can do with it other than large water wheels, otherwise you are doing an awful lot of work to get the water up high enough to do any work. Of course a very large water wheel might be able to make that happen.
However, a better solution would be to have the town near mountains or cliffs, where the water is already high above the town and the aqueducts would then be able to do their work more easily.
At that point many things could work, indoor plumbing, many kinds of physical labor, including all the mills that used to use it. A black smith could have a valve to run his bellows, the town gates could be opened with water power etc.
[Answer]
Two options:
**Electricity:**
If they're using it to create electrical power, then the town and tech can be largely similar to any earth-based city. It all depends on how much water is available, and how high of tech you want. For example, in the Northwest United States, up to [80%](http://fwee.org/education/the-nature-of-water-power/overview-of-hydropower-in-the-northwest/) of electricy is supplied by hydropower. So really the sky's the limit, you can have lights, electric vehicles, etc.
**Mechanical:**
Alternatively, since you want closer to medieval tech, you could run the power throughout your town (in pipes and aqueducts) and use it as direct mechanical power. I *think* this would be more efficient, because you're not losing power in the water -> electricity conversion, but the downside is that it's much less flexible and needs to be fixed installations. You can't have a hydro car, for example, but you could have a hydro-powered public transport system. You can also use it to run industry, like large steel mills, or manufacturing.
Another use would be as weaponry/defense. You could trap water and heat it to power catapults or cannon, or hit them with large clouds of steam. Or have rapid-flood moats that aren't up most of the time, but you can activate in case of invasion.
[Answer]
Note that I'm assuming pre-electricity technology in this answer.
For getting power from water, there's not a lot you can do with lakes or oceans. Having the town located on a river is your best bet. Also, since the flow of water in a river is caused by gravity, you could get more power from a faster-flowing section of river. If you want to have water power widely available, you'll need to distribute it across your town, which means being able to get the water from a higher elevation than the bulk of the settlement. This means that a hilly or mountainous region makes the best location.
The availability of water power would make your town an industrial center. Mining, metalworking, masonry, lumber, and textile industries all benefit from watermills. This, again, makes placing your town in the hills or mountains make sense—you'll want easy access to a mine or quarry.
The complexity of the logistics for the town depends on how large and spread-out it is. In general, there should be a dam and resevoir somewhere upriver of the town. Some larger factories or mills might be built next to the dam, to utilize a greater volume of water. After that, you will need an aqueduct network servicing your town. Exactly how this is laid out is pretty much up to you. You could have lots of small channels connected to one primary canal, or a branching tree-like network. It is important for you to have sluice gates to control water flow, so maintenance on the channels is possible.
Beyond this basic setup, what you can do with the water power is pretty varied. You could use canals and water bridges for transport around the town, or you could have water-powered cable cars. Water power could be used in the operation of city gates or drawbridges. Also, related to logistics, the city's firefighting and sanitation systems should be exceptional (as long as you can tell the difference between the fresh and waste water lines). Just beware that if you get too inventive with the water power, your setting will seem a bit steampunkish (especially if you use steam!).
The potential for population growth in the city depends mainly on the amount of food that they can get. This is the main drawback to a mountain location—most of the food will need to be imported. So the limit would be based on how easily travel is in the region, and the relationship between the water-town and the surrounding towns and villages. There are [already](https://worldbuilding.stackexchange.com/questions/4161) some [questions](https://worldbuilding.stackexchange.com/questions/9582/how-many-people-can-you-feed-per-square-kilometer-of-farmland) on this site to help with that.
So, yes, such a town could exist and function. Depending on the quality of agriculture and transportation in your world, it could even become a substantial city and trade center.
[Answer]
I haven't seen an answer involving steam yet so here goes:
Steam could be a possible water (and of course heat) based system for generating mechanical or electrical power.
Where do we get the steam from? Well the geography of your city will have most of the impact here:
Iceland for example generates about 30% of its power from geothermal sources [Wikipedia](http://en.wikipedia.org/wiki/Geothermal_electricity#Worldwide_production) and of course this comes from volcanic type activity and many many geysers.
For something like small lakes and rivers you would likely need to find a source of energy for heat. Coal, wood, or other burnable materials.
A third option which I view as viable with large bodies of water or sufficient flow rates from aquifers would be to have the sun power your steam operations. Parabolic mirrors (or giant perfectly cut gems?) could provide the heat for your system.
Lastly you always have magic as an option to generate steam and then the water source can be a bit more varied. Fire elemental cores, Rifts to the elemental plane of fire, demonic chili peppers, etc.
[Answer]
Water has two incredible properties - it does not compress, and it retains heat well.
As long as your water source is up high enough and you have constant feeds, you could create intense pressures in a pipeline and release it in short bursts, like water jets and water rockets. We already use water based cutting jets to cut through steel over 2 inches thick.
Steam would be another great resource for weapons - steam based cannons and even rifles of some kind could be created. Steam itself can be piped at temperatures over 700 degrees Fahrenheit and intensely burn attackers. Use steam like a cloud cover in winter, create snow hillsides, ice walls, and even avalanches from your artificially created snow!
In terms of supporting a town, many sawmills converted to electric generators simply to keep the tools performing well (easier to buy an electric saw these days.) however, the mill generates almost the same amount of electricity to run the saws as the mechanical power the wheel generates on its own. Remember, saw mills and fabric mills were the first real factories. If you need any mechanical energy, water can provide it.
You can easily support 100,000 people for power, depending upon the size of your water resource.
Just make sure to have more than one "pipeline" or aqueduct to support each side of your fortress. I'd make a ring of storage tanks and interconnect them to share their water pressure. If one is lost, cut it from the loop immediately or you lose pressure everywhere.
[Answer]
How about a town build on top of a lazy flowing river. The houses are build on rocky formations in the river having water wheels supplying the power for metal workers and other craftsmen. Water is pumped by the wheels up to the surrounding fields for irrigation and for running water in the town. This is all easily done even when very low tech.
Materials are transported through the town on bridges, with cranes powered by the water wheels or by boat.
To add complications plant life in the river meeses with the water wheels, those annoying beavers upstream simply will not stop building their dams, the enemies of the city notices the annoyance of the beavers and try to build their own dams, and will attack anyone trying to remove the dams.
And every spring the water rises in the river wrecking havoc.
EDIT: I forgot to mention that a tidal river could be a challenge in my scenario. The water flowing 'backwards' at times is perhaps not good for the water wheels.
[Answer]
I'm unsure of the "magic" available in NeverWinter, but so far all the answers don't really include magic in their answers, except for the construction phase for building.. a normal real-world construction.
If magic can be sustained in a way that doesn't require effort, for instance, if you can have a group of mages cast an enchantment once in a particular spot and they never have to come back unless someone else dispels it, you could essentially create even more efficient constructions.
Dams create "power", (whatever you're using it for), by the force of water moving downhill. The reason you block the water is either so you have a standing lake for other uses, or to help create pressure to generate more power.
* What if we could create "anti-gravity" areas, where the water flowed back up as well? (alternatively, magic "heated" areas to turn the water to steam)
You could essentially create a perpetual motion machine.
Take flowing water, put a wheel in it, we have a mini water-mill! Now, at the end of the wheel, use magic to make the water flow "up", or, use magic to turn the water to steam. Provide a trough or something above the wheel, to guide the water back to the beginning of the wheel. Then, allow natural gravity to take over or cool the steam back to water. You can now cut off the water source if you wish.
There will naturally still be some loss of water, so being able to "magically" create more will assist with that, or, if they are advanced enough, they could try to "seal" the contraption together so the water won't ever escape. Being able to seal it would mean you could increase the pressure as well.
---
With canals, I imagine you could design some way to control the flow of water easily using magic. Put rafts in there and you have a system of conveyor belts which could be useful.
[Answer]
As a slight aside, no one has mentioned that such an arrangement has existed in the real world.
<http://en.wikipedia.org/wiki/London_Hydraulic_Power_Company>
The "power" was just the pressure of water applied at the point required. Using a dam or just a large hydraulic accumulator filled by some other means would do the job of providing pressure. But you would need a technology for decent high pressure pipework.
[Answer]
Actually, if you think about it, a town could in reality be constructed by some of the worlds most efficient designers and workers. The water could be electrically generated through a sort of canal. All of this water could power up certain things. The town wouldn't be perfect or anything near perfection but it could be a livable place
] |
[Question]
[
If I want an Earth-like planet, what kind of star can I use to achieve that ?
According to the [Harvard stellar classification](http://en.wikipedia.org/wiki/Stellar_classification), our Sun is a G-class star.
The best would be to have:
* Temperature similar to Earth's, but can be hotter or colder as long as Earth-like beings can live there.
* The life on the planet evolved naturally and is not the result of terraforming.
* A year is more or less made of 365 days. (Ideally)
* There is only one star. (Ideally)
The answer could be whether or not an Earth-like planet is possible around different kind of stars: A, F, K, M, white dwarfs and possibly other stars. It could be more exotic, such as a neutron star.
[Answer]
I'll narrow down your list by talking about all the stars you *shouldn't* use. You'll find it gives you a pretty narrow range.
Let's start with the exciting ones: [neutron stars](https://en.wikipedia.org/wiki/Neutron_star). These are, technically, stellar remnants, leftovers of massive stars that blew themselves apart in supernovae. Supernovae are, in general, not a good thing for planets - or, in fact, anything that happens to be near the star. Given that planets would form early in a star's life (and hence pre-supernova), in many cases it's unlikely that a planet would survive. Just to mess with us, though (!), there are many cases in which planets somehow survived a supernova. Where the central neutron star is a [pulsar](https://en.wikipedia.org/wiki/Pulsar), these planets are known as [pulsar planets](https://en.wikipedia.org/wiki/Pulsar_planet). So, actually, it *is* possible for planets to exist around neutron stars. If the neutron star is a pulsar, the planet may be bathed in enough radiation that life could not exist, but perhaps life would have a chance if the neutron star is not a pulsar.
Next up: A [White dwarf](https://en.wikipedia.org/wiki/White_dwarf). White dwarfs (or *dwarves*, depending on your personal preference) are also stellar remnants. They are the remains of stars like our Sun, who have cast off their outer layers as a planetary nebula and are now merely the small remnants of their former cores. Planets *can* exist around white dwarfs - in fact, it is thought that Mars and all the planets beyond it will continue orbiting the Sun for a period of time after it becomes a white dwarf (Earth, Venus and Mercury will likely be swallowed up). Life on Europa could be given a chance when the star expands into its [red giant](https://en.wikipedia.org/wiki/Red_giant) phase, before it becomes a white dwarf. As a white dwarf, there won't be a lot of light to help shine on Europa - in, fact the Sun will cool into a [black dwarf](https://en.wikipedia.org/wiki/Black_dwarf) - but Europa could temporarily harbor life.
Now I'll go to [supergiants](https://en.wikipedia.org/wiki/Supergiant). These are the biggest of them all, the class O and B stars. They live short but exciting lives, often only ten million years or so (to put that in perspective, our Sun has been on the main sequence for about 4.5 billion years, and will live for a few billion more). They are extremely massive and very hot. Planets may or may not form here - it can be hard to detect them. At any rate, complex life will certainly not form on planets around supergiants, because of their short lifespan. Ten million years go by, and fft! You get a supernova.
Next on the table are stars more like the Sun - think [G](https://en.wikipedia.org/wiki/G-type_main-sequence_star), F, or K stars (A stars are more massive, and giant-like throughout their lives). These are the stars that get people excited, because many are [solar analogs](https://en.wikipedia.org/wiki/Solar_analog) - stars like our Sun. They have great potential for harboring life, and many think a star like this should be our first target for an interstellar voyage.
Another cool (pun intended) type of star are [red dwarfs](https://en.wikipedia.org/wiki/Red_dwarf). These are low-mass stars. They are cool, small, and long-lived, with potential lifespans of trillions of years. They could have exoplanets - in fact, many that we have discovered do - and could thus support life, if the exoplanet is within the star's habitable zone. Proxima Centauri, the nearest star to our solar system, is a red dwarf.
So out of all the basic types of stars, I'd go with a Sun-like star or a red dwarf. They have the best chances to harbor life, when compared to other types of stars.
As @celtschk pointed out in a comment above, you can change the orbital period of the planet to whatever you like by simply changing how far it is from the star. This is the simplest answer you'll get to that question. To make it more complicated, though, I'll note that if you want life to develop on that planet, you do have some constraints. The planet's orbit must be within the star's habitable zone. For red dwarfs, that means the planet must be reasonably close, and so a year equivalent to 365 Earth days may not be possible in all cases.
I'll clear up the [brown dwarf](http://en.wikipedia.org/wiki/Brown_dwarf) angle here, because there's an important distinction to be made between brown dwarfs and other stars. Brown dwarfs are "failed stars" - they aren't massive enough to sustain hydrogen-1 fusion. They are technically designated as "sub-stellar objects", and have been confused with large planets. Their masses can range anywhere from 13 Jupiter masses to 70-80 Jupiter masses. Because they don't undergo hydrogen-1 fusion, they don't emit a lot of light, and so would be poor choices to harbor life, unless a brown dwarf was orbiting another star.
[Answer]
The concept you should look into is popularly known as [The Goldilocks Zone](http://en.wikipedia.org/wiki/Circumstellar_habitable_zone). What it boils down to (no pun intended) is a formula that tells you what is the possible range of orbital radii where liquid water can naturally occur, and thus a planet where water is present can support life. You can find this zone for most any class of star.
The only caveat here is that there are two parameters you need to keep an eye on (both can also be read from the Herzsprung-Russel diagram mentioned in the article you linked), and that is effective temperature and total mass.
Mass is important because it will let you calculate the orbital period (=the length of the planetary year) for a planet orbiting a given distance from the central star. A simple estimate can be obtained using [a simple formula obtained by reversing Kepler's third law](http://en.wikipedia.org/wiki/Orbital_period#Small_body_orbiting_a_central_body). Note however, that it only holds when the mass of the planet is much lower than the mass of the star. This will most likely be the case in your scenario, I'm just including this in case you decided to go for one of the extreme ends of the spectrum.
Effective temperature is important, because it tells you the spectral profile of the light emitted by the star, as well as the total energy. As a rule of thumb, hotter stars will tend towards higher frequencies, and higher total radiant energy output.
Since you need to get something in the neighbourhood 1000 W/m^2 of incoming radiation to get liquid water, the corollary to this rule is that hotter stars will appear smaller when viewed from the planet, since you need to be farther away from them to get the same incoming radiance.
Stars that are hotter, and thus radiating more in higher frequencies, will also have significantly higher UV output, making the starlight potentially hazardous for humans. This gets lots worse as you get to the superhot stars and neutron stars, which will be emitting significant amounts of X-ray and gamma radiation, probably making the surface inhospitable.
Curiously, there was actual serious research done into what sunlight would look like on extrasolar Earth-like planets. The primary paper is *Predicting Sky Dome Appearance on Earth-like Extrasolar Worlds,* Wilkie & Hošek, SCCG 2013. You can read the paper, or at least take a look at the pictures to get a visual idea [here](http://cgg.mff.cuni.cz/projects/SkylightModelling/).
[Answer]
Regardless how hot or cold the star is, you can always place a planet into acceptable climate conditions by just putting it into the right distance. This will impact the duration of the year: for the small cold star, the planet must be closer so the year will be shorter (see [orbital period](http://en.wikipedia.org/wiki/Orbital_period)). This depends much less on the mass of the planet as it is very light in comparison to the star anyway.
As the life takes long time to evolve, it should probably be a stable star from the [main sequence](https://en.wikipedia.org/wiki/Main_sequence), burning hydrogen, not helium or anything the like. Other stages of stellar evolution (like red giants or cooling dwarfs) may be too short for creating life "from scratch" but would still fit if the planet has been colonized later.
[Answer]
Earth-sized planets can exist around any type of star; however, if what you mean by "Earth-like" is "a planet that we could live on," then the specifications get a lot more narrow.
A small star, like a red dwarf, lives for a long time but may be volatile and unpredictable on a year-to-year basis. And even if you found a particularly stable red dwarf, you would be limited by the fact that red dwarfs are colder than sun-like (F, G, or K) stars. To maintain Earth-like temperatures, the planet would either need a very thick atmosphere (resulting in high pressure at the surface) or would need to be very close to the star (resulting in tidal locking that would make one side of the planet very hot and the other side very cold). In short, it would be possible but very difficult for life to exist on a planet orbiting a red dwarf.
Larger stars, on the other hand, have short lifetimes. An Earth-like climate could exist (the year would be much longer than 365 days, since the planet would have to have a wider orbit to compensate for a hotter parent star), and the planet could certainly be habitable for a few million years, but that's the catch: it would only last a few million years. So if you're just talking about people visiting from Earth, a planet around a large star could be a good option. But don't expect it to have a full, rich history of life like we see on Earth.
[Answer]
The problem with using stars more massive than ours isn't the heat: as other answers show, just increase the distance. The trouble is the accelated lifespan. If a star doesn't sit in calm main sequence existance for billions of years, you won't have time for evolution.
You can find diagrams of the age at which various spectral types (or masses) run out of fuel. If you want something more exotic, look at the largest that provide a suitable age.
The trouble with small stars (red dwarfs), besides having to get very close up and deal with tidal locking, is that they flare all the time! However they are abundant so maybe that's the norm?
So for an Earth-like planet with a native complex biosphere, use a star like ours.
] |
[Question]
[
Suppose human explorers came across a terrestrial planet hospitable for life, but with more than 70% of its surface covered by gallium.
When temperatures rises in the day it will form an ocean of liquid metal so how do they cross it?
I am looking at interstellar tech level and also submarine will likely be destroyed when temperature drops in the night.
[Answer]
>
> When temperatures rises in the day it will form an ocean of liquid metal so how do they cross it?
>
>
>
They need to pay attention
[Liquid gallium is denser than solid gallium](https://en.wikipedia.org/wiki/Gallium),
>
> * Density (near r.t.) 5.91 $g/cm^3$
> * when liquid (at m.p.) 6.095 $g/cm^3$
>
>
>
so liquid gallium will sink under a crust of solid gallium. This means that until the whole gallium is liquid, it will be more or less like being in the polar waters, surrounded by metallic icebergs (gallsbergs?).
Once the whole body is liquid, the high density will make it easier for something to float on it, but will also give more drag.
Probably the most apt solution is to have some small submerged winglets which give portance and lift the ship above the surface of the liquid, to drastically reduce drag. Even better would be an hovercraft.
Due to the high density operating a submergible will be quite challenging. To have it sink under the surface its average density will have to be higher than the one of gallium: expect a very cramped space.
Add to this that
>
> Gallium attacks most other metals by diffusing into the metal lattice. For example, it diffuses into the grain boundaries of aluminium-zinc alloys and steel, making them very brittle.
>
>
>
and you see that it will be challenging: you probably need to have at least some polymer coated vessel to prevent gallium attack, or use a metal which is not affected by gallium diffusion.
[Answer]
Temperatures may change enough between day and night to melt the surface of a gallium "sea" but unlike water, liquid gallium is opaque, so the stellar radiation can't penetrate and even slightly warm the liquid below the surface.
Therefore, if the sea is to become liquid at all, there needs to be enough heat flux from below (from inside the planet, that is) to keep most of the sea melted, so freezing only takes place at the surface (mainly due to radiative cooling at night). The result, given that solid gallium floats in the liquid much like ice in water, is that you'll get a skim of "ice" that slowly thickens the longer the surface stays cold.
During local winter, this "skim" might get thick enough to support substantial loads, as does ice on lakes or seas in subArctic and Arctic climates on Earth. In local summer, the gallium might remain liquid day and night, or barely skim over.
As noted above, most metals are bad choices for gallium sailing -- however, composites are not affected this way. Wood, composite or inflatable hulls might be a very viable choice, with sail power (engines always seem to want to put metal parts in the "water"). The hull(s) could be very small relative to the load, compared to what water-borne sailors are used to, leading to the likelihood of tricycle layouts with small floats supporting a load-bearing framework -- more like ice boats than Earth ships.
The brilliant part of this is that it would be almost impossible for a "man overboard" to drown -- hypothermia could be an issue, over time; despite being as temperate as a tropical Earth sea just to remain liquid, the gallium will conduct body heat away far faster than even sea water, but a person would float far higher than is the case even in hypersaline water like the Dead Sea (though not anything like as high as in old pictures of huge mercury pools). Standard overboard survival drill would be to lie still, on your back, with arms and legs spread for stability, and wait for rescue. Swimming would be more like crawling in very soupy mud than what we're used to.
[Answer]
Any flat boat type will do. Propelling it might prove tricky, but people solved that satisfactorily thousands of years ago by using sails. You might also use propellers like a hovercraft does, but I wouldn't bother with actually hovering the craft. That would just be a waste of energy.
If you worry about drag, that's not a problem once your craft gets fast enough. It'll just rise out of the gallium and glide across its surface. Just like speed boats do on water. But at much lower speeds. I'd wager that even rowing boats would be built to rise out of the gallium. You will also get much less waves than you would get with water, so gliding is even more fun.
What you absolutely must worry about is the fact that that gallium attacks other metals. You must build your ship in such a way that no gallium can ever get into contact with vulnerable metal. Even in the case of accidents. It would just be too sad if your boat scratches a stone, and subsequently falls apart while it's on the high seas! As such, a coating is not enough. I would strongly advocate for building the entire supporting structure of the boat out of inert materials. If you need to resort to wood, so be it. But a 100% plastic boat would be more likely, imho.
[Answer]
As posted on an answer above, liquid gallium would sink under solid gallium, forming a crust. Potentially, a tank type vehicle with rubber/polymer treads would spread its mass so much that when it traverses over solid gallium, even a thin layer, it does not crack it. Even if the gallium is liquid, it could maybe still be traversed using tracks (exploiting the high surface tension) and a retractable "skid" (to lower ground pressure even more).
I drew a design of what this vehicle might look like: [](https://i.stack.imgur.com/wawcs.png)
The vehicle is so large because it is self contained: it contains all the life support and equipment that the scientists may need to operate for a long time independently. Due to the sheer size of the seas (and their extreme viscosity), something that skims over them at a fast speed can only sustain short journeys, as it requires quite massive amounts of energy to propel such a vehicle at this speed over liquid gallium (and this kind of vehicle may also need to stop at night). If scientists need to get to somewhere far away, they might as well make a slow "crawler" base and slowly travel to where they need to go, as this would expend much less energy.
[Answer]
**Maglev ships**
Magnetic levitation is possible over any well electrically conductive material. It's just a technical problem to precisely manage the AC magnetic fields required, but the technology exists already. It's no issue for interstellar civilization, even if complicated by sea waves.
] |
[Question]
[
Let me introduce myself. I have a twin. We are around our 30's. Even though we are pretty similar (and it's rather obvious we are twins) we are easily distinguishable if you pay enough attention.
The interesting part is that we have telepathy between each other.
This telepathy works as follows:
* We can *turn it off/on* whenever one of the two wants.
* When *turned on* we share all thoughts and sensorial input.
* Our brain got used to work with this shared information, so we don't usually get confused due to that.
* It's a bit like having two screens in front of myself: One's what I see, the other what my twin sees; I can easily focus on *my* screen, change focus, or try to pay some attention to both.
* Same's true for the rest of the senses.
* About thoughts, it needs to be more conscious, and basically, we can *hear* each other with our inner voice.
* Our telepathy *travels* near the speed of light, so it's effectively instantaneous (at least on earth).
Taking that into account, now I wonder: **How could we exploit our telepathy?**
We are not concerned with moral values but are worried about the risk of getting caught doing something illegal. Our main target would be to get money and power.
Edit a bit of context:
We live in nowadays World. In any suitable country for your answer. We are average, in education, economically, socially, etc (according to the country you choose).
[Answer]
So the ability you two have got is communication without any physical/known channel. Making money with this ability is relatively easy, however gaining *power* is quite a different (and complex) thing.
Here are some of the methods you can use to win a lot of money in little time.
# 1- Chess
Yes, chess. Both of you guys learn some chess (beginner level is enough). Let all the people know you are interested in chess. Now just about a month after you guys have started chess, one of you goes on to start challenging chess players in order of increasing expertise. First, a local club player, then a senior club player, to candidate master to master to international master and finally a grandmaster!
The twin who is playing chess would be helped by the other twin, who would use a top chess software to help his sibling with advice on what to play. Considering that some chess programs are even higher rated than grandmasters, he would go on winning match after match.
For the final match (a challenge to a grandmaster) you would want to invest a **lot** of money on a bet that you would win. The stakes would be really high for the grandmaster so you would likely get a 1-20 or even higher bet rates. Invest all your property in the bet. Get bank loan, lend from loan sharks ... anywhere you can get a scrap of cash.
Win this match and you would land around 50 million dollars or so, with all the bets and rewards from chess organizations for being a chess prodigy and whatnot.
# 2- Magic Performer Shows
This goes like this. You guys change your appearances. One of you goes on to become a stage magician. The trick he is going to be famous for, is that he can tell what is being done on the stage, even when he is blindfolded completely, with earmuffs and facing away from the stage.
You get any random people from the audience to come and do something on the stage. You get the information about their actions through telepathy and while blindfolded, talk loudly about what is going on at the stage.
You would quickly become more famous and successful than David Copperfield, rolling in cash.
# 3- Clairvoyant
This should be simple enough. You set up a small group of followers by telling them about news of the world (which are conveyed to you by your twin) and this group grows as you are seemingly aware of the occurrings in the world without any communication links. You get to be a renowned clairvoyant, start advising people on complex matters of life and whatnot and get to become a highly paid ghost communicator and all.
[Answer]
## Secure Data Delivery
Suppose a big scary government agency or shady corporation needs extremely sensitive information moved. They can't trust couriers, and they can't transmit it electronically because it could be intercepted. *If you can be trusted,* you could dictate information from one twin to another. Big scary governments will probably pay you plenty of big scary hush-money for your services.
## Cheating on Gameshows/ your SATs
If your abilities are kept secret, get one twin on Jeopardy while the other uses Google. Rake in your reward money, rinse, and repeat. Also, you could easily get a full right through university by doing the same with your SATs - assuming you don't bomb the writing section too badly. For that matter, you could appear to be a test-taking prodigy as long as one of you can stay on a computer. You can be dumb as bricks and graduate with a 4.0 from Harvard.
## Master Assassins
One of you goes for dinner with target X. The other camps up on a building with a rifle, taps into the others senses, and lines up a perfect headshot *through a solid wall.* Vary this theme until it fits.
[Answer]
## It's really not that big a deal
Almost anyone can do what you do. Send information around the world takes only a common smartphone and we can share almost all senses instantly. All feats you can do together with your twin can be copied with current technology. The only exceptional thing you have is that you don't need a micro-camera to see and can possibly send through radio-jammers and you are undetectable.
But almost all options to use telepathy to cheat at gambling, do a magic show or lead a cult could already be done with some sophisticated technology. And not the kind which is really stunning, but the kind which almost anyone assumes the MI6 has since James Bond movies.
## This leaves only danger and magic-tricks
So the only two places where your ability comes in handy is doing actual magic tricks. Getting bounties for paranormal phenomenons or letting your audience check all frequencies of radio, letting yourself be locked into a solid metal box and still know everything your twin can see and so on...
The other option will involve a lot of risk, where you could share information from military,political or organized crime targets, who guard themselves against all forms of surveillance. But this will need a lot of skill and training and will be very dangerous.
[Answer]
## Come out and show the phenomena to the world
Become famous showing real telepathy. It will be a unique magic show.
Also, there are a lots of prizes for a proof that telepathy is real:
<https://en.wikipedia.org/wiki/List_of_prizes_for_evidence_of_the_paranormal>
[Answer]
Playing cards where one of you is the player and the other just tries to get glimpses of other peoples cards. In order not to look too suspicious it would be best of you try to distinguish yourselves as much as possible (different hair style/colour, etc).
[Answer]
**Information** is the most valuable commodity being traded today. Your abilities should exploit the gathering and transmission of information that you shouldn't have and that can be gained quickly. Cards and parlor tricks might put some coin in your pocket, but controlling information will gain you power and fast.
But you will need to keep your abilities secret - that's information that can be used against you and put you and your brother in mortal danger. You will also need to decide who the face of this "game" is going to be or operate in tandem in different parts of the world. You will need to become adept at negotiation and possilby a little black mail, here and there - but not for money; for position.
Stay far away from covert operations. You become the commodity and one that will either serve the "company" or one that becomes expendable due to non-compliance. Tune your observation skills and always watch your back. You'll need to become a little paranoid once you start down this path.
[Answer]
Find a *really* good lawyer and patent your ability, and any other paranormal abilities you can think of which could possibly be related. Most likely this would be best in conjunction with a major research university - say MIT, for example.
Because your next step is to start a research program with yourselves as the test subjects. By definition, if it's having an effect on a physical system (the brain) then the effect is measurable. That means the cause is measurable too, and that means you can bring telepathy and/or other paranormal abilities to the world as a technology. If you've got the patents, you're basically sorted for life. And famous as the people who changed the world forever, too
] |
[Question]
[
I'm imagining a super-powerful spacefaring race which has the capability to build or modify a star system or even galaxy by moving stars around, but I wonder if it's really feasible.
Is it theoretically possible to move a star intentionally and accurately from point A to point B? How might this be done? How would it affect anything near the star, orbiting and otherwise?
[Answer]
One proposed method of moving a star is to build what is known as a [Shkadov thruster.](http://en.wikipedia.org/wiki/Stellar_engine#Class_A_.28Shkadov_thruster.29) Essentially, this is a large shroud covering half of the star, which is held up by the pressure of outgoing solar radiation and the solar wind.
Reflecting the solar wind on one side of the star creates a momentum imbalance which, over millions of years, can be used to steer the star though space.
[Answer]
There is the law of conservation of momentum. When you throw something into a star, the resulting momentum is the combined momentum of object and star. So you can change the velocity vector of a star by colliding it with other masses (by the way: the same method works on black holes).
Unfortunately for this to have an effect, these masses must be either very large or very fast, preferably both. Unfortunately, both can change the star in ways you don't want.
Adding more mass to a star makes it burn faster and ramming it with a mass with relativistic speed might destabilize it. We don't actually know much about the inner working of stars, so it's hard to say what exactly would happen, but it likely would not be very healthy for anything orbiting said star. Heavy coronal mass ejections, unpredictable fluctuations of luminosity (up or down) and extreme solar flares should be expected. So when any planets orbiting the star harbor life, they likely won't anymore afterwards.
Speaking of planets: Their orbits will change. Accelerating the star in one direction is equivalent to accelerating everything it orbits in the opposite direction, so the orbits of any planets will likely become a lot more eccentric or the star might even lose some planets or collide with them (this applies to any method of accelerating a star which doesn't also directly accelerate the planets).
[Answer]
Depending on how realistic you want your solution you could have your advanced race use **folding space**.
All objects in the universe are moving, probably very fast! So, for example if you wanted to move the whole solar system, you fold an area of space larger than the solar system onto another area of space and wait for the solar system to cross the boundary.
Gravity would most likely be able to cross the boundary too so you'd want to choose two areas that had similar "base" gravity. Also, regular momentum and angular momentum need to be conserved (unless they do something else clever).
So moving the solar system anywhere else within our galaxy would be tricky as it would have to be moving faster, slower or in a different direction than originally. Removing the Sun's mass from one part of the galaxy shouldn't be enough to destabilise the galaxy, nor would inserting it somewhere else. The nearby stars would just adjust themselves a little bit although long term the effect would be chaotic, i.e. unpredictable the longer into the future you go, but still stable or non-catastrophic.
You would also have to think about the effects of a gravity "shock wave" when you first connect the two areas of space, and also when you disconnect them.
[Answer]
With something as large as a star - wow. Tricky, and there's also the problem of slowing it down once it's where you want it to be. What would be the purpose of moving a star vs keeping it where it is? One method - rather slow, would be using gravity assists, flying large spacecraft or shooting asteroids or comets around it, either giving the star or taking from the star, orbital velocity around the center of the Milky Way - but we're talking about an enormously slow process.
Another method might be magnetism. If we could trigger sunspots on a star (say by shooting it with electrons in one spot and protons in another spot - oh, say, 10,000 or 20,000 miles away, you might generate a sunspot and coronal mass ejection on one side, and reduce them on the other side using the same method. Enough sunspots on one side of the star would slowly generate movement. There might be other ways to trigger coronal mass ejections - not sure, but that would be one method.
Another method could be to feed one side of the star with a more easily fusion-able material, such as Tritium, or perhaps a Lithium Isotope, which (might) - I don't want to say it would but it might have an effect like throwing pine needles on a fire causing the star to go "whoosh" and shooting more energy out of one side of the star (I'm not sure the specifics how fusion and whether that would occur close enough to the surface to actually have that effect - just an idea).
None of these methods would be fast - but I have to ask - why would you want to move a sun or star? I can see needing to if a star was on a crash course for our solar-system and we might want to move our sun out of the way (a slow process to be sure but if we had 100,000 years warning, we might just be able to do it).
[Answer]
I would say using and then destroying blackholes on the side of where you wish the star to be pulled towards. Even better, it could be a wormhole where the material and light being sucked in on the one side, funnel back out on the other side for both a pull and push.
Opening and closing blackholes is already possible on a very tiny scale inside the hadron super collider. It is reasonable to surmise that at some point in the near or distant future, controlling the opening and closing of wormholes could become as trivial as downloading a file off of the internet is today.
In this illustration, the matter from the star is being pulled into the entrance. If the gravity well of the wormhole is of sufficient magnitude, the star will move very quickly without having much matter pulled in.
The largest problem in moving a star, is something I would call `orbit locking`, in which you may succeed in bursts to pull the star away from its current transient position, only to release it into another locked orbit or zone due to other surrounding stars and planets in the vicinity.
Using this mechanism, you could open and close the wormholes in bursts, to give the star inertia, and then you could use smaller wormholes in the reverse to slow the movement down as it moves closer to where you wish to move it — kind of like like applying brakes at a stop light, or using inverse thrusters on a rocket to land.
Hope this helps, and good luck on your intergalactic travels. Please don't move our sun, or if you do, push it a bit closer to Canada -- it's freezing here :)
[Answer]
## 1
Consider a binary system where gas from one is falling into the other, as is commonly the case when the larger becomes a red giant first.
Use magnetic effects to channel the plasma (if the infalling material is not sufficiently charged, take care of that first) to fall onto one pole, rather than all around the star. That will generate thrust as a jet.
## 2
Magnitar — shape the magnetic field to interact with the enclosing galactic field, or with generated magnetic fields. Or, manipulate it to cause a jet to point where you want, and kill the opposite jet.
## 3
Any star with a pair of jets, cover one to reflect the thrust. That's essentially the same idea as the shroud posted in another answer, but easier to steer.
Niven & Benford induce a jet in a red dwarf by using a shroud and aim the jet through a hole in the hemisphere.
## 4
Generate gravitational waves at different locations and focus them to constructively interfere near the star, making a gravitational gradient that the star falls towards.
## 5
Use a "warp drive" to shorten the distance in front and lengthen behind, with *the whole solar system* in the middle rather than the typical ship. As a plot device, you could have the "payload" required to be a huge mass, so that's the way to travel.
## 6
Wormholes. Supersized.
## 7
Pseudo-reactionless drive. Convert some stellar material into dark matter, beamed in one direction. It's a jet without the mess. Again, make the density and mass of the stellar core a necessary part of how it works, so it's not just showing off but *the* way to make it work.
## 8
The matrix. Hack the database to change the game board of the simulation we call the universe.
## 9
Exotic physics, teleporting momentum. Two stars can essentially repel each other without any standard force between them that anyone would notice.
## indirectly
Given some means to move an *exotic* object, or that the mechanism would make things inhospitable, you move one star and have it pass near the one you want to move *carefully*, towing it gravitationally, slingshotting it, perturbing its galactic orbit, or whatnot.
## unexplained fictional physics
Any common SF device like inertial dampening fields, shrink rays, tractor beams... can be **supersized**. E.E. "Doc" Smith had the good guys move planets using the same engine as used for ships: already bought-in to the story's suspension of disbelief, just supersized.
[Answer]
In theory you could create a magnetic field large enough to influence a star, also if you have the technology to use the fictional science of Cavitronics you can manipulate gravitational singularities on a whim so you could move it that way. What that is going to do to a star's internal processes I haven't a clue, I'd guess it would be bad though. Having got something the size of a star moving you have to stop it too which could potentially be much harder, precision movement with masses that big is really hard, momentum is not your friend when you have no friction to counteract inertia. The effect on the rest of any solar system associated with a star on moving the primary is going to depend on how you're moving it but in general I'd expect it to be catastrophic at best, enough gravity or magnetism to move a star is going to make nothing of a planet.
Of course if you have access to grade two Cavitrons you can build artificial star-like objects anyway so moving stars kind of becomes moot; instead you just feed the star you don't want to the Cavitron to get an artificial star-like object with the same mass-energy as the fuel star only where you want it instead of where it was.
[Answer]
Instead of a hovering material, just put a ridiculous amount of mirrors into orbit. Then spin the mirrors precisely so it's exact rotation speed coincide with it's position in orbit. Where it would face towards the sun on one side and continues its spin so that they'd face away from the sun at the opposite side.
] |
[Question]
[
A lot of fictional works contain people who are well over 100 years old, some 200, some 1000s of years old. The Emperor Of Mankind for example is over 10,000 years old. Colin from Highlander is over 2000 years old.
Realistically, how would these people think and act? How would they act or think differently from ordinary young people, assuming that their physical bodies do not age (e.g remain the body of a 30-year-old)?
My guess is firstly that they would know lots of facts, but not necessarily in depth as they may not have had the time or resources to conduct research into these areas. They might have a very well developed philosophy, taking some axioms as far as you can go by pure logical reasoning. Their decisions might be more logical and they might be faster to make decisions, so that they might be more perfect Bayesians. However, given that their brains are still only human (or slightly superhuman), they would still just be boundedly rational agents. Would they be rid of all addictions and bad habits, including bad mental habits? Would they have conquered procrastination? Would they reach the limit of expertise, or somehow go beyond it?
More importantly, how would they speak, act, and make decisions? Would they sound like otherworldly beings, or just like an ordinary friendly guy who seems trustworthy and knowledgeable? Would having so many years of experience and learning give them some unique insights not available to normal humans?
EDIT: You can take Colin MacLeod from Highlander as an example. Regular human given the gift of immortality who lives through normal human history as a regular human being (not a slave but not a king either, perhaps ordinary citizen).
[Answer]
It's difficult to say without having any first-hand knowledge of such a phenomenon, though I would imagine that a good model for a person living to the age of 600 would be to take the central differences between a child of 6 and a grown person of age 60. Why 60? Because this is a safe age to extrapolate behavior, after which, behavior might begin to suffer from the onset of old age. Since they will have the body of a 30-year-old, I assume that diseases such as alzheimer will not have an effect.
So what are the central differences between a 6-year-old and a 60-year-old? This in of itself is a difficult question to answer because it mostly depends on the individual, however I think we can agree that generally, you see the following traits in 6-year-olds that you wouldn't see in 60-year-olds:
* Immaturity
* Egocentric world view
* Innocence
* Irrationality
* Impatience
And so logically the type of traits you'd typically see in 60-year-olds (and again, not always) would be Maturity, Accepting world view, Knowledgeable, Rationality, Patience. Therefore presumably a 600-year-old is just a more extreme version of this.
Extreme maturity - They likely wouldn't appreciate humor as we appreciate humor, and even then, they would likely find little funny, save for very sophisticated and subtle humor which might easily go over our heads. For the most part, they'd be like stereotypical tight-lipped librarians that want nothing to do with the silly things you do.
Extreme accepting world view - Little is likely to surprise them, since they've seen everything before. The ideas that they've had over the years has solidified into granite and therefore they realize that they aren't going to change ideas. And it's not without a certain irony that this also means that they've made up their minds regarding their approach to such contrasting ideas. You aren't likely going to be able to trick one into arguing with you, but if you could and assuming you were listening, it is far more likely they'd tell you something to put your own ideas into question. Their general approach to differing world views is likely going to be apathy.
Extreme knowledge - There will be little that they do not know. Although they may not have knowledge on par with an expert in the field, they will certainly have enough base knowledge to ask a question that may stumble an expert in most fields. The type of knowledge known for the fields that interest them is unfathomable, though suffice to say that they will likely learn neighboring fields at the level of expert simply because the two fields have some common ground. In other words, a 600-year-old biologist would likely be able to tell you anything you'd want to know in the areas of chemistry or zoology, at the extreme of being considered an expert in both fields, as well as quote the first chapter of Dante's Inferno by heart just because it is a hobby of his.
Extreme rationality - A 600-year-old man would be able to argue circles around you, thinking several steps ahead. This is not necessarily because he is smarter than you, but simply because he's had a lot of time to practice. Suffice to say that after you explain the rules of chess to such a man, he'd likely not lose a single match and by the third game, he'd have figured out how to beat you in 10 moves or less playing off your own strategy. This isn't to say that such a person couldn't be wrong, but his beliefs would be deeply rooted in fact that you couldn't prove him wrong without first showing that one of these facts is fundamentally wrong as well.
Extreme patience - You would not likely see a 600-year-old man show a temper. Combined with extreme rationality and you'd feel like you were talking with a living version of Spock. In fact it would be difficult to evoke a strong sense of emotion of any kind. These types of emotions would be likely limited to only friends and loved ones and only in specific occasions.
Could a 600-year-old man be immature, egocentric, innocent, irrational, impatient? Yes, absolutely. This is merely a generalization, though you likely wouldn't see 600-year-old individuals if they did show these traits, because like children, they would "grow out of it" more likely than not.
[Answer]
Physiological considerations aside, this is what I see as the differences:
**Slower Thinking / Decisions:**
Old people make decisions more slowly than young people. Research indicates this is not due to cognitive decline but instead old people must sift through a greater quantity of data (life experience).
**More Cautious:**
Older people tend to understand the likely risks and consequences of a given course of action better than young people. They would tend to wait longer before making decisions and try to gather more information before making the decision.
**More "In the Box" Thinking & Decisions:**
All people rely on analogous experiences to figure out how to approach new situations. Older people will have determined certain approaches work better than others in most cases and will reuse successful approaches. In most situations this will lead to quicker better solutions than a young person can devise. However, in novel situations in which people have no analogous experiences, this approach could trap them into solutions that don't work.
**More Conservative Thinking**
As a general rule, old people have more to lose (family, wealth, etc.) than young people. They also have a lot of prior experience on how to preserve things. This will lead to a more conservative approach for how to deal with new situations (how do I keep from losing those things precious to me). Young people would be much less likely to take this conservative approach.
**The Long View**
Very old people will be *better able* to take the long-view. They will have a greater understanding how their decisions and thinking might affect themselves and others over much longer periods of time.
Also note that many people perfectly capable of doing this still won't. It's just that old age provides the framework which allows them to better understand these things if they choose to do so.
[Answer]
The way people think would depend on the life stage they are.
People who are eternally young, will eternally think like young people. People who stop at "mature adult" will think like other mature adults. People who grow old, but simply never die, will think like other old people.
A person who has lived over several eras does not fundamentally differ from a person who has lived in several cultures. That is exactly what the immortal would be after all. A relatively young immortal could be modelled by an immigrant from a foreign culture. The exact issues vary with original culture so the match is not exact with any actual actual group of immigrants, but if you look at issues common to most immigrants, the immortal will have experienced them to some degree.
For older immortals you can look at groups that generally have lived in several cultures such as cultural anthropologists and retired military who have spent their lives overseas in several different locations. This depends on whether the immortals try to blend in or have their own society. Which obviously depends on how common the immortals are.
Most knowledge and training has specific context it is relevant and becomes simply a curiosity over time. Most mortal people (certainly here in world building...) have few areas of interest where they know lots of generally useless trivial. The immortal would not really be qualitatively different, but quantity and breadth would be larger. But, of course, after a certain point quantity has a quality of its own so the **really** ancient might be weird enough for it to matter.
The immortals **might** try to make their knowledge relevant by choosing fields such as archaeology, history, writing historical novels anthropology, or acting as occupation. Or they might choose areas where the practice they had centuries ago might still help such as mathematics, many forms of music, dancing or martial arts. Realistically, the immortals would have enough accumulated property to live without an actual occupation and no more trouble picking up an entirely new occupation than any other person of their apparent age.
[Answer]
If I knew I were immortal, I would spend most of my time trying to acquire new skills. To some extent, this is necessary just to survive. After all, whatever earned money 200 years ago is not necessarily relevant today. But it also means that the immortal would have time to learn music, art, history, and science, assuming a human brain can absorb all that knowledge. Unless the immortal had an IQ of 90, in which case they would likely live hand-to-mouth until they eventually died.
The easy route to survival is to be a mercenary and work security. Physical combat of the bar bouncer variety hasn't changed much over 600 years, so you should be employable across time quite well. An unambitious highlander might well resign himself to this rather boring fate.
A traveler might expose him/herself to all the world's cultures, even though that exposure will itself become obsolete with time. The extra time could be leveraged into a master level of diplomacy (imagine just 20 years with Rosetta Stone), or squandered on SnapChat.
It all boils down to how ambitious such really old people are. Even today, some old people go on cruises, while others watch t.v. in a retirement home. The interesting ones are the ambitious and active ones, and these would continue to gain skills until they were obviously more talented than everyone else around them. Given how often ideas are rediscovered, this person could simply appear more intelligent than everyone else simply by remembering stuff that happened hundreds of years ago.
[Answer]
One possibility that has been neglected in other responses is that they simply wouldn't (at least act.) This is the route of the Antediluvian vampires in World of Darkness, and a real-world example of the psychological type (though not due to extreme age) might be the mature Cratylus of Athens, a radical student of Heraclitus of Ephesus. The mature Cratylus would not even speak, so paralyzed was he by his extremist process philosophy. Whereas Heraclitus claimed that one cannot step into the same river twice, Cratylus insisted that you cannot even do so once. The contemporary philosopher Graham Priest suggests that the mature Cratylus may be the best candidate for a real-live believer in trivialism, the view that all propositions are true. Priest claims that such a one may not take any action, because action entails a desire to make something the case, but the trivialist already believes that everything is the case. (Though, conversely, the trivialist also believes that everything is not the case, so it's really a coin toss.)
Perhaps better than having all your ancient masters be Cratylus-clones would be to give them all extreme commitments to some philosophy or another. Most of these would tend to be paralyzing or self-destructive in some way, however, so you may end up with a split class of ancient masters: the retirees who are paralyzed by their philosophies, and the actors who eschew philosophy or simply refuse to commit to a particular point of view.
[Answer]
Depends of his personality, if he lives forever or for very long times he might choose to enjoy the stupid phases of a human a little bit more because **a person changes his attitudes depending on how many years left he thinks he has and how easily he gets tired** or because he was very close to die or believes in something greater than himself
Remember that most humans care most about the pleasures of life, and some don't want to stop enjoying but time makes them to do something meaningful before they die.
Although years give you experience and experience can make you wiser, people like to have fun because its fun, imagine that it was impossible for a human to live more than 21 years, he would be very wise and giving the best of him at around 17-19. Do you think they would live with the same attitude like a 17 kid from today?
But some young people have a personality of an old person.
Sometimes personality and attitude count more to give the best of us than a skill or ability.
If Einstein had lived 500 years we can say he would be the same because he always was like that and what he did was his pleasure.
If a person who you don't like because of his actions lived forever do you think he would change his attitude at 100 years old? he might he might not.
Most of the people tend to act according the judgement of society, look at him he is 45 and still not married, that person might want to get married, but if the youngest age to marry was at 120 in a world where people lived 800 years?
more years give you more experiences for good or for bad.
```
How would really old people think or act?
According to his/her personality.
```
[Answer]
When I read your question, I immediately thought of Gulliver's Travels. The [Struldbrugs](http://www.shmoop.com/gullivers-travels/the-struldbrugs.html) are a race of immortals living amongst the ordinary, mortal citizens of Luggnagg. However, the issue is that they age like normal humans.
Therefore,
>
> Once the struldbrugs hit 80 years old, they have "not only all the follies and infirmities of other old men" (3.10.13), but they are also extra-opinionated and cranky because they're worried about living forever.
>
>
>
Their lives are really awful. Because language is constantly changing, eventually nobody can communicate with these Struldbrugs. They have no life-long friends, as who could stand another human being for all eternity? In addition, to avoid the monopolisation of the world by Strulbrugs, in Luggnagg these immortals become legally dead at the age of 80. In accordance with this law all of their property and finances are taken away at this point in their lives. In theory, it sounds vaguely reasonable, but when it is put into action, it just means that the streets are littered with incredibly ugly, incoherent and grumpy beggars.
In this universe, I think that the reality of immortality would be different. But this novel presents the idea in a very interesting manner.
[Answer]
This question really depends on many factors, such as when the person was born and what sort of personality they have. If the person was born around the time of the Spanish Inquisition (and supported said inquisition), they would no doubt be highly disillusioned with the rise of secularism and the separation of Church and State. Maybe they would eventually begrudgingly accept it. Maybe they would fight an eternal battle to overthrow those changes. You have a lot of room for creative freedom here.
**If the person knows they are immortal**, I would imagine that they would be very risk averse and patient - even when they are young. Mere mortals know they are eventually going to die, so we are all forced to come to terms with it one way or another. Immortals will not. They can also work on building their lives on extraordinarily vast timescales. Even if the best job they can do is work as a laborer, they could put aside some of their income, invest it, and over the centuries become immensely wealthy. They could defer starting a family indefinitely, as well.
**Politically**, they would first and foremost support ideologies that afford them greatest personal protection. If immortality is rare, I could also imagine that they could see themselves as superior to mortals and use this as the basis to create an immortal aristocracy or autocracy. Given the power and influence they would accumulate over time, class separation between immortals and morals is inevitable. That could also drive social unrest and resentment. Note that, over time, the number of immortals would steadily increase, so even if it is rare they could still exist in substantial numbers.
**As for speech**, the person would likely use an antiquated form of their language. However, if you have a substantial immortal upper class, it is likely that the entire evolution of the language would be influenced by this. Older phrases would remain in use for much longer, for instance. In this case their language use would be considered a standard dialect, rather than "outdated".
There are countless other scenarios we could explore here: the question is rather broad.
] |
[Question]
[
A medieval European ruler (specifically whom and of what country doesn't matter, but may be specified by an answer) one day finds in his bedchamber a group of textbooks and self-improvement books. These books cover a variety topics as understood by modern civilization: logistics/supply chain, industrialization, specialization, leadership, management, and project management. For each topic at least a dozen books directly deal with it, and these books offer multiple angles of discussion, multiple contexts, and multiple opinions on each topic, giving a well-rounded discussion and documentation of each topic. Each book also discusses the stages of advancements of the theory and practice (divorced of such specifics of time and place), so one can understand how each of these topics progressed or regressed over time. Lastly, these books cover how these topics interrelate.
Magically the ruler, his advisors, his noblemen, and his scholars can understand the textbooks (overcoming boundaries of language and cultural context), and thus they can gather understanding of the topics by reading and contemplating the material. The ruler calls all those who can read these books together to study them, and they collectively agree that these were written by a more advanced civilization than their own, and the words should be valued and sought to be understood and then applied.
None of the textbooks discuss modern hard-science, technology, or engineering. The books have also been magically reproduced with period-specific materials, and so the books themselves hold no particular value outside their content (and whatever value being simply a book in that era holds). To rephrase: besides the book-learning, theory, case examples, etc, that they provide there is no noteworthy value to the books.
How valuable actually are these books in terms of potentially resulting economic advancement, and how significantly would the introduction of these books alter history in terms of social and economic advancement?
[Answer]
The books offer very valuable information, however implementing their lessons will be next to impossible - at least not for a long time. The reasons are many, and varied:
**Education**
These systems depend on an educated workforce capable of carrying out your instructions. Sure, the low-level worker doesn't need to be too bright, but the supervisors, managers, etc. need to be able to read, write, understand the big picture, some basic metrics, etc. etc. etc.
The army is about as close as the middle ages got to "large scale logistics", and that had nobles involved at almost every level of it - they were the educated ones (and even then, only barely).
So right off the bat you don't have a workforce to implement your concepts, and most likely lack the resources to educate them. (you would need to set up schools, find tutors, educate them so that they may teach others, and more importantly find a way to displace all those workers from the military and agricultural roles they are needed in).
**Infrastructure**
The world as it exists today takes quite a few things for granted. For example, we live in nations in which the populations are relatively homogeneous from a cultural point of view. We have laws which are enforced by police departments state wide, and military forces to keep our enemies at bay. War, famine, and blatant abuse of power on the scale of the middle ages (by nobles, or kings) are basically unheard of in the western world.
All of this, along with our roads, railroads, and telecommunication networks give us a huge edge. Project management is basically the logical outcome of organizing all of these resources, which do not really exist in the middle ages.
The middle ages, however, were not known for their political and military stability. That was the age of city states. An insulted noble would rise up against his king, raiders would wipe out entire villages, or ambush and kill travelers, etc.
The political and military landscape is too unstable for large scale (kingdom wide) projects to really be implemented.
**Religious Conflict**
The middle ages are also quite famous for witch hunts, wars among religious factions, and the inquisition, to name a few. The Church wielded a massive amount of power, and was obscenely rich to boot, making them a power to be feared.
If the rumor of these books "appearing" in your kingdom surface you may quickly find yourself labelled a heretic, possessed by the Devil, or worse. Your "strange" ideas and concepts alone may gain you a multitude of enemies, even in the ranks of your own nobles and clergy, who may see efforts to educate the plebs as a danger to their own power.
**Conclusion**
Not only would this king lack an educated workforce, but also the infrastructure to set up any large scale project management. However, this knowledge does offer the potential to shape the kingdom for generations to come.
Assuming that your kingdom is powerful enough to survive for a few centuries, you should be able to set the foundations of a mighty nation, maybe even an empire.
Keep your knowledge a secret. Gather those who see these texts as a miracle to your side, and form a secret society sworn to guide the kingdom into a brighter future. Indoctrinate the noble-born youths with this purpose, and begin to build upon the principles in those texts.
Start by setting up some automation or help for agriculture, etc. Secure your borders without a doubt. Apply some of those lessons to make your military more efficient. Develop better methods of communication. Establish an educational system. And as the generations pass, your people will rise above all others.
[Answer]
The primary difficult you run into is a **different economic foundation**. Specifically, monarchic and feudal systems, while they use currency as a means of exchange, are largely rooted in a given dynasty's right-to-rule. The serfs would provide food and other wealth to those in charge, who in return would provide protection and to a varying degree infrastructure.
The reason a lot of modern ideas work is because the economic foundation is instead a capitalist or pseudo-capitalist system. A secondary but related issue is the **notion of self**. If there is a pervading idea that the nobility is noble due to a congenital quality, the basis upon which a lot of current thinking resides doesn't exist in a medieval setting.
That said, there is one area that might reap a real benefit: [Double-entry accounting](https://en.wikipedia.org/wiki/Double-entry_bookkeeping_system): or, to put it another a *rigorous way of accounting for resources*. This was invented in the 1300s - so it was technically a medieval invention. Having it earlier, though, allows for a more efficient allocation of resources. Further, this only needs to be taught to a few administrators who are likely to already know math. Related to this, banking can be used to decrease the number of resources left laying around.
While a lot of logistics and supply-chain management was already practiced (especially militarily), the concepts were, again, rooted in a medieval world: unstable conditions, including disasters, drought and pestilence, would make it such that predicting your supply chain was dodgy at best - thus making it as efficient as possible won't really help. Instead, these books would likely indirectly point to areas where development of hard, physical-science and engineering progress will yield the greatest rewards: increasing the amount of food per acre per farmer, storage and shipment of perishable goods and the means of forestalling disease and dealing with it if it occurs. Finally, the fact that precision tooling and replaceable components are very efficient - and researching ways to build and utilize those is of keen import: easy replication leads to more rapid advances. (A printing press to disseminate information would be lovely for this specific reason.)
In sum, there would likely be some acceleration in some areas, perhaps moving the historical timeline up a hundred years or so. But it would be difficult outside of specific scientific information to do better than that, because of the way the economy, government and psychology of the time interacted with each other.
[Answer]
Modern logistics are a stretch, in my opinion. However Roman logistics in the middle ages would be a game changer. Romans were the first to think about campaigns in terms of thousands of tons of food.
[Answer]
The problem with your premise is that all these things exist in their modern form because they solve (or allegedly solve) a particular problem. So in addition to the [impossibility of implementation mentioned in this answer](https://worldbuilding.stackexchange.com/a/57416/4981), you have a bigger problem - even if you could implement these modern techniques, they wouldn't be useful to a society at an earlier level of technological development.
Project management, for example, exists in its current form because [building Polaris-class nuclear submarines was to complex to be managed the old way](https://en.wikipedia.org/wiki/Project_management). Project management only ever even came into existence as a discipline because around the 1900's, engineering projects became complex enough that managing them they couldn't be handled by the lead architect or engineer, as was traditionally done.
Likewise, industrialization (as another example) came about to solve the problems encountered by industrial-era Europe, particularly, the problem of producing large quantities of particular items. To oversimplify things a bit, in the middle ages, it was sufficient to have a small number of craftsmen in each locale making products for the small, local population. Once European populations began growing large enough that their needs started to out-pace what could be supplied by skilled craftsmen, it made sense to invest a lot of money and effort into specialized manufacturing facilities that could leverage economies of scale into making a particular item in mass quantities. But time shift that factory back into the past a couple hundred years, and it's not useful - great that you can use it to crank out 10,000 shoes a day, but there are only a couple hundred people in that medieval village, and what are they going to do with thousands of extra shoes? Their cobbler already makes as many shoes as they need, so having all the villagers stop farming to mass-produce shoes (or whatever) not only doesn't solve any problems, it creates new ones, like mass-starvation because there's no one growing food anymore. Industrialization only makes sense when there are economies of scale to be leveraged, and your typical medieval society isn't large enough to have any.
In short, Medieval Europe (and societies at that level of development in general) simply didn't have the problems that these modern techniques solve, so in all likelihood, the knowledge would be largely useless, relegated to the fate of a curiosity or party trick, like [the steam engine invented by the ancient Greeks](https://en.wikipedia.org/wiki/Aeolipile). A couple thousand years later, steam engines changed the world, but at the time, there was no practical problem that the Aeolipile solved, and what it could do (convert chemical energy into physical force) was more cheaply and easily done with slaves. These modern disciplines you mention would likely suffer a similar fate, if transported back in time or technological development, somehow. They're designed for problems that wouldn't exist, and come with a cost. In an era where literate people are rare, and educated people are even rarer, you simply wouldn't get an advantage out of allocating those rare human resources to perform functions that aren't needed.
[Answer]
Leadership is almost identical today to what it was in the past. The primary changes are adjustments to culture differences. As a project manager myself, I don't see any value in introducing a dozen conflicting project management methodologies over whatever the experienced managers used in these times - they might get inexperienced managers up to speed slightly faster but that's it.
In all the things you mentioned, there's only one thing which significantly differs from what was known at that time:
Industrialization.
The assembly line and the moving assembly line, as well as large scale factories employing those would completely change history. If the books also contain information about industrialized agriculture - specifically the parts that don't rely on resources that were unavailable at the time - it's a complete rewrite of history. Whatever country obtained these books would end up as a mass exporter of goods, massive influx of wealth, and large population growth sustained by early industrialized farming.
At this point you really have 3 competing results. A large amount of people combined with excess wealth in a period of great change means there will be unrest in the lower castes, which likely results in a change of government. Alternatively the people and the wealth can be used to wage war on other nations. The third competing result is that you'll end up being invaded because of your wealth. Probably all of these will happen in more or less the same timeframe.
With a period of wars and civil wars, the outcome is really quite unpredictable. It might lead to a unified Europe, or it might lead to industrialized salt production being used to salt the earth all over Germany.
[Answer]
>
> These books cover a variety topics as understood by modern civilization: logistics/supply chain, **industrialization**, specialization, leadership, management, and project management.
>
>
>
As soon as you have industrialization, you are out of the middle ages.
The value of the rest of the books pales in comparison to this. Some of the ideas that ended the middle ages are not very advanced or complicated. We just didn't stumble upon them, for some reason or another.
The first steam engine was built in the 1st century AD. No one figured out a way to use it. No one thought that rotational movement could be turned into useful work. One of the first uses of modern industry was to suck water out of mines using simple engines. This could have been done at almost any point in history. Mechanising water removal allowed much more coal to be mined, giving the fuel needed to expand industry in other areas.
The same thing happened in farming. Industrial techniques allowed for 1 farmer to do the work of 50. The 50 unemployed farmers became the workforce of the industrial age.
Almost everything that kickstarted the modern age and ended the middle ages was simple enough and could have been done at almost any point in history.
This doesn't mean that your kingdom will be pumping out the Model T in 5, 10, or even 15+ years time. Knowing that machines of type "X" are good for doing work of type "Y", is a ***huge*** leg up. Just being told that you can use *machines* to do *work* would have been an inconceivable concept at some points in time. But once that concept is in your head, there's plenty of applications available that we just completely overlooked.
] |
[Question]
[
A person from the 15th century Europe, by way of an [Assiti Shard](https://en.wikipedia.org/wiki/Assiti_Shards_series), gets thrown forward in time to 21st century New York City. They are aware they're going someplace weird, because the shard manifests as a glowing door opening out of thin air.
Now, it is imperative that I be able to return the person to their original timespace location, or very close by. For that, the past visitor would have to be able to return to a specific location (in Chinatown, behind a stinky dumpster) a week after their arrival in NYC. You can assume that they are made aware of this somehow.
The person is a XVth century scholar, versed in Latin, some Greek and several local-time dialects of French and German. They have no money, no ID, do not speak the modern English language. **Would they be able to survive and elude capture for a week?**
My thinking so far:
a) It's New York, so not speaking the language and looking a bit disoriented should make them fit right in.
b) Cars and traffic lights - dead.
c) Police - unclear if they'd get arrested, as long as they don't get violent.
d) Food and water - unclear, since they have no money.
[Answer]
Yes they could.
It is true that they wouldn't know how cars, traffic lights, etc work. However, it seems likely that they would realize "I probably shouldn't walk out in front of the big things that are moving really fast". Then other people who know how traffic lights work would start walking when the lights change, so they would learn to follow what other people are doing. Given time, they might figure out what the rules are, but if nothing else they could survive by following the crowd's behavior.
Police likely wouldn't arrest them unless they try to do something they shouldn't. They'll probably be rather unclean, wearing clothes that have seen better days... Basically, they'll look like any random homeless person. So unless they do something blatantly illegal (and the moral code hasn't really changed THAT much - no stealing, no killing, etc etc) they'll probably be more or less ignored by the police.
So the question then, is how can they get food and water, and get back to the Chinatown dumpster at the right time, when they have no money and don't speak the language.
**Churches.** They're a scholar from the 15th Century, so that means that they're probably from a religious background. They'll recognize a church, especially a bigger cathedral like St. Patrick's. If they find a church, they're set. They can get food, water, shelter, and, most importantly, help with getting back to where they need to be.
See, they can communicate with a preacher. They have a built-in translator: the Bible. There are Greek and Latin translations of the New Testament all over, and those will be (essentially) the same that they're used to (the languages haven't changed much). So if nothing else, they can communicate by pointing at words that the preacher can translate. Also, knowing Latin makes it really easy to fake communication in any of the Romance languages - French, Spanish, Italian. Coupled with their knowledge of (15th Century) French, communication shouldn't be too much of a problem once they can get a dialogue started.
The trick, of course, is that there are a LOT of new branches of Christianity that they won't know about; Martin Luther wasn't born until 1483, so the Reformation hadn't happened yet. Our protagonist won't know about the existence of Lutheran, Presbyterian, etc, and will therefore be in for some shock unless they happen to find a Catholic church - though they've just moved forward 500 years, so there's going to be culture shock anyway.
So long story short, unless they get hit by a bus or something before they figure out not to walk in the roads, I think they should be able to survive.
[Answer]
**There is a good chance he gets killed by disease in a week,** since there are dozens of pathogens he has never encountered before. Even if he is not killed, he is quite likely to be at least somewhat debilitated by sickness.
Barring that, **survival is quite likely**. A key question to how it will go is whether he will establish communication.
**Survival without communication** would not be particularly difficult. Copying others would be the key survival strategy.
* Barring a freak accident, he would not get killed by a vehicle. It is not particularly hard to avoid this once you see the danger and act cautiously. Following others across the street would work fine.
* He would most likely avoid trouble with the police simply by observing and mimicking acceptable behavior. The police don't go around looking for medieval people with no ID to arrest them. You have to cause a disturbance (a pretty large one) for them to even notice you. This could be easily avoided.
* Food could probably be obtained simply by body language like pointing. People would take pity on him and give him something to eat. Note that food wouldn't even be necessary to survive a week, and he might prefer not to beg. But it would be relatively easy to get some food if he was willing to ask for it.
* Water, the main need for survival, is available freely from many sources (drinking fountains, sinks in bathrooms, etc.). He is likely to discover these readily, or he may be given some water when begging for food.
I see no problem with him surviving the entire week, even if he doesn't establish communication.
**Survival with communication** would be a lot easier, though. Whether anyone would believe his story is doubtful, but it is likely that if he comes in contact with the right people they will take a great interest in him, given the unusual dialects he speaks. This is probably enough to ensure all the free room and board he needs for a week.
**Establishing communication may be possible.** All kinds of languages are spoken in New York, and it is also a tourist city. He may hear someone speaking French or German, or he may see the ubiquitous tourist guides and maps that are available in many languages. Once he understands that there are people in the city who speak his language, he can go around making statements in his language in the hope that someone responds.
He will encounter plenty of French and German speakers, but it's not clear how intelligible the 15th century languages would be to them. I'm not an expert. However, if he spoke the language of northern France at the time, which was closest to modern French, it seems there is a good chance a modern French speaker would understand him. The German language did not begin to be standardized until the publication of Luther's Bible in 1522, so he may be unintelligible depending on what German dialect he speaks. Note that neither French nor German would be used by scholars in the 15th century. Latin would be his best bet for communication if he is able to encounter modern scholars, but obviously he is less likely to meet people on the street who speak Latin.
If he finds someone speaking his language, his hope would be to be directed to someone with specialist knowledge of his dialect for better communication. A tall order perhaps, but maybe even tourists can direct him to prominent Universities?
[Answer]
Cars and traffic lights: I doubt this would be an issue. Sure, he doesn't know how an internal combustion engine works. Neither do 90% of the people in New York. But he's presumably quite familiar with horse-drawn wagons, and he knows not to jump in front of those. If he sees a large object moving at high speed, he doesn't have to understand how it works to know not to jump in front of it. I'd think he'd figure out traffic lights pretty quickly. He sees all these vehicles racing along and then they all stop. There are these big lights hanging above the street. How much genius does it take to notice, Hey, when the red light comes on, they all stop. Even if not, he waits until they stop before crossing the road. Even if he times it wrong and he's still in the middle of the street when the light changes, plenty of modern Americans cross streets when the light is against them. He might annoy drivers but he'd be in only slightly more danger than the average pedestrian.
Communication: Where in Europe is he from? If he speaks English, sure, the English he speaks will be very outdated, but people will understand him. He's from the age of Shakespeare and the King James Bible. Modern Americans struggle with Shakespeare and Jimmy, but they can understand them. If he speaks Spanish, there are lots of people in New York who speak Spanish. I don't know how much Spanish has changed since 1500, but if it hasn't changed more than English has, same situation. Failing that, a big city like New York is used to having tourists who don't speak the language. No one would be shocked by his speech, and people are used to trying to communicate with foreigners by pointing at things, pantomiming actions, etc. If he doesn't find someone who speaks his language he's going to have a hard time engaging in a serious philosophical discussion or getting any sort of abstract information. But he should have no problem communicating simple things like "I need food": I think pointing into your open mouth and rubbing your stomach would work in many cultures. If he runs into the authorities, they'll search for an interpreter, and finding someone who speaks German, French, or Greek wouldn't be all that hard.
Police: Assuming he's just trying to survive and get back to the exit point, I don't see why the police would bother him. He has no reason to murder or assault anybody. He's probably not selling cocaine or engaging in insider trading or operating a coal mine in violation of environmental regulations. He might look and act weird, but in a big city, there are lots of weird people wandering around. I don't see that he'd have an issue with "avoiding capture". New York police are not normally on the lookout for time travelers from the 15th century, and while New York has a lot of bizarre laws, I don't think they have one against time travel. Oh, if he's carrying a sword or some other medieval weapon, that could get him into trouble. Besides that, the only likely source of trouble I see would be if he steals food to live or breaks into a building to get shelter from the weather.
Which brings us to, food and shelter: As others have pointed out, water wouldn't be much of a problem: there are plenty of decorative fountains and public water fountains in New York. It wouldn't take long to figure them out. Food is harder. He could try begging. There are plenty of homeless beggars in New York: no one would find this startling. Someone mentioned that he would surely recognize cathedrals, maybe other churches if they have a prominent cross. Someone at a church would surely try to help him. Churches in big American cities routinely expect to help poor and homeless people.
Beyond that, we're back to communication. If he is able to communicate, if he speaks English or Spanish or manages to find people who speak his language, he might learn that some random object he is carrying is a valuable antique that can be pawned. Any coins he is carrying would surely have value. If he asked around he might find an odd job to earn some money. He might run into difficulty that he can't legally work in the U.S. because he doesn't have a social security card, but plenty of businesses hire people under the table to avoid taxes and regulations. If he can't communicate, getting any sort of work would be hard.
With no identification, he might get into trouble as an illegal alien. But American police don't lock someone up just for being an illegal alien. He'd be told he has to appear in court on such-and-such a date, and he'd be gone long before then.
He might have the strange problem that if people tried to help I'm by giving him money, he wouldn't know what it was. Paper money was not introduced in Europe until the 17th century. If he can communicate, no problem: He says, "Huh, what's this?" and they say, "That's money. Don't you recognize American money?" He might struggle with the concept but, etc. But if he can't communicate, it's just an odd-looking piece of paper. Why are people he asks for help giving him pieces of paper?
If he tells people that he's a time traveler from the past, they might think he's nuts, but other than telling each other, "Hey, this guy's nuts", I don't see any more coming of it. It's illegal in the United States to lock someone in a mental hospital unless you can prove that he is a "danger to himself or others". If he's not threatening to kill himself or attacking other people, no one's going to lock him up. There are plenty of people in New York who think they've been kidnapped by aliens or are the rightful heir of some fortune. No one worries about them much.
It suddenly occurs to me that you didn't specify whether he knew he was going to travel to the future and had time to prepare, or if this happened to him unexpectedly. If he had time to prepare he could bring along a week's worth of food, make sure he had clothing suitable to the season, have some gold or silver for trade, maybe even bring a tent. Then he just camps out in Central Park or wherever for the week and it's no trouble at all.
[Answer]
No utterly unfamiliar with technology or the Customs of modern-day New York. assuming he didn't go insane, he'd probably be hit by a car or have some other accident happened to him. Not to mention the guy would have no way of getting food and water without any modern currency.
I don't think he would be arrested unless he did something really stupid, most that saw him would assume he was just another homeless person. He might be put in an asylum if he told people where he was from but I don't think he would live long enough for that to happen.
The only way he would survive is if he got someone from the future to help him but anyone kind enough to help him from our time would probably just put him in the psych ward.
If he had the skills to survive in the wilderness then maybe he could take shelter in New York Central Park at least for a time.
[Answer]
A week shouldn't be a problem. His biggest problem would just be convincing people that he isn't crazy or an illegal alien that is crazy. You could just also have him befriend some other guy from behind the dumpster who shows him the ropes of living behind a dumpster, soup kitchens and all - he could live like a king for a week like that.
If the person has seen different cultures already then it becomes just easier. If he can get hold of a dictionary then it becomes much easier. Also he could just see some shop with text that he can recognize.
Surely he would be familiar with the concept of money and begging already as well, which could go a long way.
I would think the tactics for survival would differ if he knew he was getting out in a week though - if he didn't know it, he would need to start making some more long term choices. If the police did catch him he would probably end up in a custody for a while though, as they would figure out he only speaks old dialects, has no papers and no identity.
[Answer]
There are quite a few movies exploring similar scenarios:
[Kate & Leopold](https://www.imdb.com/title/tt0035423/) 19th century gentleman arriving in new york.
[Just Visiting](https://www.imdb.com/title/tt0189192) (and sequels) 12th century knights arriving in different modern times and areas (including new york).
[Black Adder: Back & Forth](https://www.imdb.com/title/tt0212579/) The beloved black adder travels to different times and places. A bit sketchy and strickly speaking not new york.
Needless to say back to the future might also hold some valuable insights.
Maybe you can get a few inspirations from them.
] |
[Question]
[
In a video game series called Portal, we are given a gun, which shoots two portals: an orange one and a blue one.
These portals have the following properties:
* Anything that goes into the orange portal comes out of the blue portal (instantaneously), and vice versa.
* Only two portals may be fired at any one time; if another blue (orange) portal is fired, then the already-existing blue (orange) portal will disappear and be replaced by this new portal.
* Portals can only be fired onto flat, stationary $^1 \ $ surfaces. If a portal is fired onto a stationary $^1 \ $ surface, and the surface then moves $^1 \ $, then that portal will disappear.
* Portals may not coincide (i.e. two portals can't be in the same place at the same time)
* When an object travels from one portal to the other, momentum is conserved, relative to the portal normal.
i.e. $p\_{\text{initial}}=p\_\text{final}$, or, in other words, if a body enters one portal with a given velocity, it will exit the other portal with the same velocity.
This picture succinctly demonstrates what's going on:
Now, assuming that such we can create such a gun, does the existence of these portals contradict any of the laws of physics? Is their existence possible, in theory?
---
$^1$ Relative to the planet that both the gun and the portal are on. For some reason, if the gun and the portal are on different planets (say, if you shot a portal from the Earth to the moon) this rule [doesn't apply](https://www.youtube.com/watch?v=3NABJVXOgiA&t=4m50s).
[Answer]
There was a paper on this when portal came out, though I cannot seem to find it right now.
The end answer was **Yes, portals are physically possible, but the picture is *probably* not.** The worst hand waving has to be done in the process of making the portal. Defining *why* two sections of space-time would get cemented together in this way is a job for worldbuilders like us, not for scientists.
Instantaneous communication is no problem, because we could curve space-time to make the link. Effectively this would decrease the "straight line" distance between an emitter and a receiver to keep the speed of light rules in place. There would be some annoying General Relativity effects during the process of placing the portals to deal with, but I don't think it would violate anything. It'd just be nuisance.
Conservation of energy requires a bit more excitement. After all, Portal's ability to break the laws of physics in this way were legendary. Most energy is conserved without effort. Momentum in equals momentum out, and that accounts for a great deal of the potential conservation issues. However, there's always gravity.
**These portals would need to interact with gravitational fields to avoid violating the conservation of energy**. Whatever the underlying mechanism is for gravity, it would have to bend the direction of gravity around the portal. It would, in fact, have to bend the direction of gravity *everywhere* to ensure gravitational potential energy can still be modeled as a divergence free gradient field. Hopefully the mechanic would be localized, so it would have less and less of an effect as you walk away from the portals, otherwise people on the other side of the world would notice when you plopped them down. That being said, the more "evil" you are in your portal placement, the more the laws of physics will have to be "creative" to keep the laws intact.
The picture of how portals work would *probably* not apply. Because you simply jumped off a ledge and were carried by gravitational energy to the portal, through it, and off to the far ledge, the far ledge would need to be at a lower gravitational potential even though instinct directs us to assume that, because its "higher," its at a higher potential energy. We are used to working in fields where gravity always points down. I would expect most "reasonable" portal field implementations would not have this behavior (for a reason I'll mention at the end), so it is unlikely but not impossible that the picture would work.
**Now for the hard parts**
The edges of the portals will be tricky. As Peter Masiar put it, we like space time to be continuous. These sharp edges will end up being mighty torrents of quantum rage... not infinitely thin, but you'd have to spend a lot of work stabilizing them because... well... you cut a hole in the universe pulled itself through itself, and then glued it all together. What do you think would happen? *Fortunately, the portal graphics clearly show this chaotic dangerous region around the edges. For your safety and the safety of others, please do not lick the edges of the portal*.
The final issue would be the nastiest: the energy of creating a portal. When you drag spacetime around, the conservation of energy is STILL in effect. If you change the direction of the gravity field, you will need to effectively recalculate the potential energy of every object in the universe. If you "raise" the universe, you have to put energy into it as you make the portal to offset this potential energy. If you "lower" the universe, it will emit energy which will have to be reclaimed, or lost as gamma radiation. *Don't have any tumors? Well, unless you're wearing lead lined underwear, we've taken care of that too!*
So in the picture example, if you do the following:
* *Rest state A*
+ Place the portals
+ JUMP!
+ Disassemble the portals
* *Rest state B*
Then you MUST have put in m*g*h worth of energy into the portal to lift you from *Rest state A* to *Rest state B*. It looks like that's about 2m higher than before. The portal gun has to do the work... you don't get the energy for free.
Also worth noting is that the gun doesn't get to "know" how you plan to use the portals, so it probably wont get to be so efficient. It will probably have to warp a lot of gravity and "move a lot of objects." Likely it will require a nuclear power station's worth of energy to generate a consistent gravity field, and then unleash a nuclear bomb's worth of energy when you collapse it back to normal (with the difference between work in and "loud bang" out being exactly 1 Chel mass \* 9.8m/s^2 \* 2m. *I tried to weigh her, but the scale couldn't display enough digits*).
**So sure, you can bend the laws of physics to make the portal work. You just can't break them.**
[Answer]
The main problem with the portals is that while they maintain kinetic energy (your speed going in) they do not maintain potential energy. That's why you can put one portal in the ceiling, one in the floor, and fall through going faster and faster.
That fundamentally breaks the law of conservation of energy. The only way it is possible is if the portal generator is adding energy into you to make up the difference.
[Answer]
It's been assumed that the portals work as wormholes, changing the topology of spacetime. But, what if that's not how it works? It could be teleportation ports instead. I recall a book series where "fax" technology had nanomachines that disassemble and analyse what is pushed into it (the plane of nanotech seems to be a portal) and another one can reproduce it. That could implement a portal in principle without twisting physics at all, reducing it to normal stuff: communication bandwidth and power input. Going in and coming out at a substantial velocity would be a challenge to the engineering, but in principle does not require new physics. The receiving end applies velocity to the atoms it's arranging at the surface.
[Answer]
They...oh wow they violate so many rules, but really it's such a violation I'm having trouble even knowing where to begin to articulate all the rules they violate lol.
so they violate thermodynamics a tim said, effectively creating free energy. if you have a way to do that you can pretty much break every aspect of the universe, thermodynamics is the driving force of everything.
in addition the violate the laws of inert. They also allow instantaneous communication across indefinite distances which violates relativity and the speed of light limitations.
[Answer]
The portal gun has a miniature black hole inside it. If Aperture Science has found a way to contain the gravity well, it makes sense to assume that the portal gun can "harvest" energy from the gravitational force itself. So the energy required to hold open the portals comes from the black hole contained in the projector.
[Answer]
Portals following those rules violate the laws of physics in several ways.
First, energy and momentum aren't just conserved globally, they're conserved locally. They obey continuity equations, which tell you that in order to get them from one place to another, they have to travel through the space between. There's a lot of quantum mechanics that sounds like it breaks that rule, but it doesn't.
Second, the portals don't conserve momentum at all. (Yes, GLaDOS was wrong about that.) Momentum is a vector. It's not just an amount of stuff; its x-, y- and z-components are separately conserved. Changing its direction disconserves it.
Third, any requirement that something be stationary violates Galilean relativity. It gives one frame of reference special status. The portals you describe conserve (specifically) kinetic energy in the frame of reference where they're stationary, but not in others. Consider the case where the two portals are side by side on a wall. In the frame of reference where the portals are stationary, an object moves with constant speed v directly towards one portal. It emerges from the other portal with speed v in the opposite direction. In the frame of reference where the object is initially stationary, it emerges from the second portal with speed 2v.
Fourth, the portals violate Einsteinian relativity. They permit instantaneous transmission of information between locations, and therefore they require time travel. Since there's some confusion about why those are related, let me explain. Suppose you travel instantly from point A to point B. According to an observer moving (rapidly) in the direction from A to B, you arrive at B before you leave A. Since all frames of reference are equivalent, you're free to travel from B back to A instantaneously in this other frame, thus arriving at A before you left, killing your own grandfather, etc.
Now, with general relativity you may (or may not) be able to create wormholes which change the topology of spacetime and bring previously distant locations close together. But I think it's sort of guaranteed never to be useful. I mean, we're talking planet-destroying bending of spacetime. Picture pinching a balloon to bring two distant points on its surface together. And you're still constrained to obey causality.
[Answer]
I think that the question we ask is all incorrect because if you think about the quantum physics, you wouldn't be able to sustain the load of particles inside of it. The only way to sustain a force of that kind of strength is to have negative amounts of energy inside, and is possible, but the force is powerful enough to destroy a moon.
] |
[Question]
[
I was wondering how effective nuclear shelters actually are? If you assume that your house is equipped with a bomb shelter (aka fall-out shelter). The construction of the shelter is not over the top, just a concrete lined bunker set into the ground say 3m below the surface of the ground. (which is already quite OTT)
Questions:
* how devastating is the explosion of a nuclear bomb? what damage would occur to the sub-structures and for what distance
* how fast does the radiation spread? could you be effectively notified via cellphone to "bunker up?"
* how long would you need to stay in said bunker (if you can actually survive the other effects)
[Answer]
Historically, the two nuclear devices detonated in war have been set off in the air. So I'll look at those for the effectiveness of bomb shelters.
If you are Ground Zero, you're probably screwed. about 50% of the total power of a nuclear blast is unleashed as a pressure wave. While you are underground and that offers some shelter, the pressure will propagate through the ground as well, and still hit you with enough force to, likely, liquify your organs. A 1MT nuclear device produces an overpressure wave strong enough to inflict heavy lung damage for 3~4 kilometers, not counting the rupture of blood vessels, etc. Again, this will be dampened by being underground, so dial it back a bit, but it's a reference point.
Part 2 of the blast is Thermal Radiation...heat. You can pretty safely ignore this if you are in a bunker, the ground eats up thermal radiation with ease.
Ionizing Radiation makes up about 5% of the blast strength, and this is pure radiation...it moves at the speed of light.
The last 5-10% of the power of the explosion is in residual radiation, which is what we traditionally think of when we think 'Fallout.'
So, as for how your bunker will do against a hypothetical 1MT nuclear device...
**Blast wave**
If you are within 2.4 km, you are likely dead from overpressure, and your shelter probably collapsed. Out to about 6.2 km, you might survive it, but will probably be bleeding from some orfices and be rather bruised. Beyond that, you might be a bit battered, but should otherwise be okay
**Thermal Radiation**
You are underground, you can pretty much ignore this.
**Direct Radiation**
A properly constructed Fall Out Shelter is designed to reduce the effects of radiation by about 1000x. So, while those on the surface are going to take a lethal dose of radiation out to about 2.3km, and will be quite screwed all the way out to 2.9. You can reduce your radiation exposure by 1000x, since you are in your bunker. So, if you are far enough out to survive the blast wave, the immediate radiation isn't really a threat either.
**Indirect Radiation**
This stuff gets carried a really long way. On the plus side, it decays exponentially. Roughly 70-80% of the fallout from a nuclear explosion (it is scattered wide, not in big chunks) has decayed within 10-20 days, and it has dropped to reasonably low levels within 100 days. But again, your bunker allows you to reduce radiation exposure by 1000x, so you are still safe, and can probably emerge in less than 100 days, provided that repeated nuclear attacks aren't occurring.
**The Problems**
If you are within 19km, you need to be in your bunker when the bomb hits to avoid injury. If you are above ground, the thermal blast will give you first degree burns across any part of you facing the blast (15km = 2nd degree, 12km = 3rd degree, within 10km, you, and everything around you, are now on fire.). You still have time to get below ground before the fallout starts coming down, but you are definitely injured. The thermal radiation is one of the longest range effects of a nuclear blast...being underground when that happens does a LOT to protect you.
Your bunker also needs some more advanced equipment...air recycling and cooling especially. You can't vent to the outdoors, that's full of fallout. And dirt is a great insulator, so you'd overheat within days.
Thankfully, you would probably have notice of an incoming nuclear strike before it hit. We are really good at figuring out missile trajectories, and if an ICBM was headed your way, a warning would go out to seek shelter before the bomb hit...then it's a race.
And aircraft dropped bomb would be harder, as would a suitcase nuke. But, in general, if you are outside of 19km, you could survive this 1Mt explosive without being in your bunker when it hits. Closer and you'd be injured, but might survive, too close, and you are dead meat.
So, all that said, early warning is the best protector against nuclear strikes, if you have a shelter to hide in.
[Answer]
I once visited a professional cold war era nuclear bomb shelter in Berlin. It had a capacity of around 3000 people, air filtration systems, food and water reservoirs, the works.
Also, according to their info it would do a fairly good job to protect you against the the actual blast and initial radiation and heat wave - a direct hit not included. But that is the *easy* part!
Air filtration systems will have to change filters regularly, otherwise they clog up and everyone suffocates. Water and food will run out. In the case of the Berlin shelter, we were told that supplies would last about 1 week tops, if the bunker was at full capacity (apparently that was about standard at the time).
**But what then?** You'll have to evacuate 3000 people from the middle of a highly radioactive field of debris. There will be no cars, hell, there will be no roads! The officials in this bunker told us that you would need to get all the people to a distance of at least 100km within 4 hours to avoid serious radiation poisoning (yes this depends on a lot of factors). Well, without cars or roads you know this isn't going to happen... Meaning while everyone survived the blast, they die a week after getting out from radiation sickness.
My point is: a bomb shelter which protects you against the initial blast is the *easy part*. But to actually help you survive it must be stocked for a *very* long habitation, and/or it must also provide you with effective means for you to **escape the radiation zone** after your supplies eventually run out.
>
> *If I could pick, I'd probably go for haz-mat suits and off-road motorcycles for everyone in the bunker. That might give you a chance to get away with most of your DNA still intact. ;)*
>
>
>
[Answer]
Fat boy was the larger bomb that was dropped in Japan during ww2. This bomb is estimated to have been 18-21 kilo tons. The largest bomb built was 50 mega tons (2,500 times stronger). Built by Russia, at the time they claimed the ability to make a 100 mega ton bomb by replacing the lead component with uranium. (The bomb used lead to reduce fall out for the nuclear test.) Most modern nuclear warheads are 12-24 megatons with the ability to device into 12 charges and hit 12 targets with a single warhead making each 1-2 megatons. Roughly 50-100 times more powerful than the larger bomb in ww2.
For the air inside a shelter blast valves are needed for the air vents to prevent over pressure and super heated air from forcing its way through those. Cheyenne mountain (NORAD mountain) is rated for a 30 megaton blast at a distance of 1.2 miles. At weakest point is 2,000 feet of granite. The entrance is on a side tunnel which is down a mile off a curving tunnel. It has a 23 ton door and then another 23 ton door.
] |
[Question]
[
\*By complex life, I mean something more complex than microorganisms. Something closer to what we have on Earth.
Similar to this question: [Is it possible for life to evolve on planets without water?](https://worldbuilding.stackexchange.com/questions/1029/is-it-possible-for-life-to-evolve-on-planets-without-water)
Is it possible for an atmosphere to sustain life without oxygen? Could life evolve with other gases?
[Answer]
Keeping things to the kind of metabolisms we see on Earth, **sure, this is absolutely possible.** Even on our oxygen-rich planet we still find obligate anaerobes, to which oxygen is a poison. In fact, your own cells will undergo anaerobic respiration when oxygen-deprived. (This tends to happen after strenuous exercise).
However, respiration with oxygen is much more efficient, approximately 15 times more efficient than anaerobic respiration in your cells. There are some anaerobic organisms which use different electron acceptors than oxygen to narrow this gap a bit.
[Wikipedia is a good start for the basics.](http://en.wikipedia.org/wiki/Cellular_respiration)
There is also the [electron transport chain](http://en.wikipedia.org/wiki/Electron_transport_chain), the summary of which tells more about the role of oxygen.
[Answer]
Yes.
One option would be $\rm F$ (the challenge to overcome is it's relative rarity compared to $\rm O$); or $\rm NF\_3$.
A proposed biochemical mechanism I once saw for photosynthesis/respiration cycle could be between $\rm CF\_4+N\_2+H\_2O$ and $\rm NF\_3 +$ carbohydrates
There's an extensive discussion of various non-oxygen options (Sulphur, fluorine) in [this article](http://www.bibliotecapleyades.net/vida_alien/xenology/08.0.htm) on "Exotic Biochemistries" from Xenology Research Institute quotes Carl Sagan, Isaac Asimov and Dr. Peter M. Molton at the University of Maryland, with extensive discussion on alternate biochemistries, including non-oxygen based. The article is very heavy on detail, including analysis of reactivity, energy required to fracture various types of bonds, rarity of elements, possible reactions, etc...
[Answer]
Oxygen breathing is not required to support the life; most of organisms can also use other metabolic pathways to get the energy. Removing all oxygen from the Earth atmosphere would be apocalyptic of course, with most of animals dying immediately, however some plant species may survive on anaerobic breathing during the night (plants produce plenty of their own oxygen as long as photosynthesis is running). Anaerobic bacteria already living in oxygen-less places of Earth would not notice anything wrong happening and will take over leading the evolution.
Disappearance of the ozone layer will increase the UV radiation. However this [work shows](http://ies.jrc.ec.europa.eu/uploads/fileadmin/Documentation/Reports/Global_Vegetation_Monitoring/EUR_2006-2007/EUR_22217_EN.pdf) that sea water (with usual particles in it) also provides efficient protection, so water organisms should probably survive, even if affected. UV-proof shells and scales may evolve.
However oxygen is also an important part of protein, DNA and cell membranes that are all very essential components of every living cell, as well as water that is also essential. Nitrogen and fluorine are not replacements, these elements have very different properties, same about hydrogen. Sulfur is somewhat similar and may substitute oxygen in some degree, but all molecular composition of life must be redesigned.
[Answer]
Certainly. We already know of different ways to produce energy without oxygen and [organisms](http://en.wikipedia.org/wiki/Anaerobic_organism) that don't require oxygen or are even harmed by it. So you definitely can have life without oxygen.
However, how complex can that life be? Oxygen powers the [citric acid cycle](http://en.wikipedia.org/wiki/Citric_acid_cycle), which produces an average of 30 units of energy, (ATP), compared to anaerobic which can produce about 2. This is a massive energy jump. Without oxygen, I don't see any large multicellur organism developing that can move quickly under its own power.
Additionally, without oxygen and the ozone it forms, your world would be at the mercy of ultraviolet light. This light can break chemical bonds necessary for life and damage DNA. Without oxygen to form a cover, life has a much harder, maybe even impossible time to survive. Life would have to remain under rocks or far from the light of the sun to survive.
[Answer]
Sure!
We already got some examples, just do a little research for Anaerobic Organism. Good point to start:
<http://en.wikipedia.org/wiki/Anaerobic_organism>
No Oxygen is really not a big issue I think, but no carbon would be one.
Even, if there are theorys of silicon based life, instead of carbon based.
This would not be possible on the external circumstances as we have them here on the earth (temperature, pressure,...) due silicon is solid matter here, but why couldn't be life on a 500°C survace-planet on silicon base?
If you think about that, you can not say that higher life without oxygen is inpossible.
] |
[Question]
[
Constructed languages are the life blood of imaginary cultures. If a culture speaks an earthly language, how can we be expected to believe that we are in a different culture? While every detail is important, one that is often ignored is symbols.
Many people that construct languages tend to think that as long as the lexicon and grammar are well made, then the symbols do not matter.
What are some tips for designing good symbols for a constructed language writing system?
[Answer]
You may find that when you start designing characters for your language, they feel somewhat contrived. In order to avoid creating a writing system that doesn't fit the language, you first need to define some aspects of your language:
* Is the language meant to be ancient or modern in your universe? Writing systems tend to simplify over time because nobody wants to write characters that are 42 strokes each. See [Cuneiform](https://en.wikipedia.org/wiki/Cuneiform_script) versus the modern [Latin](https://en.wikipedia.org/wiki/Latin_alphabet). Think about whether the culture behind the language is old enough to have developed simplified writing systems.
* Is the system going to be an alphabet, a syllabary, or logographic? You're obviously familiar with alphabetic language, but syllabaries and logographs can give a different feel to the writing. Use a syllabary if you want your words to have relatively shorter written representations. Use logographs only if you're up to the task of developing hundreds of distinct symbols; they may be worth it if you want to give the language a particularly alien character (at least from a westerner's perspective).
If you gave us more detail about your language in general, we may be able to provide more tailored advice.
EDIT: It may be worth noting that a language can be alphabetic in general but incorporate a handful of logographs to represent very common words. For example, let's imagine a futuristic flavor of English in which the plebes tire of writing "you're" — it's a whole six characters after all! In that event, we may adopt a character that *isn't* part of our alphabet and has no English phonetic value (perhaps µ) for the sole purpose of representing "you're". Consider adding logographs as mix-ins of this sort to spice up the writing system.
I hope you're having a good day!
I hope µ having a good day!
I envision the high school students of this parallel universe avoiding logographs like the plague in the interest of reaching their page requirements :)
[Answer]
In addition to the [excellent points raised by Alex Clough](https://worldbuilding.stackexchange.com/a/49388/349), remember also that writing systems, just like spoken language, *evolve* over time.
For instance, consider a language that was originally logographic as it began to become a written language. Over time, as the language expands to incorporate more objects and -- much worse for logography -- abstract ideas, as well as begins to form a grammar to convey not only those ideas but the relationships between them, the writing systems will begin to evolve to correspond. The end result could very well be an alphabet based on an ancient logography.
Take the word "eye" in English. In a hypothetical ancient logographic version of English, "eye" would of course be represented by a drawing of an eye, which over time could have become simplified to look something like this: êçà. As the language later begins to evolve into one that is more alphabetic, common logographs could be drafted to serve as the new letters, specifically those that they start with: The 'êçà' logograph becomes the letter 'êçà', the first letter in the word "eye". Combined with the letter 'Y' -- itself a simplification of the logograph for a yak -- the word "eye" in this hypothetical version of written English is "êçàYêçà". (NB: In this example, further simplification could result in the letter 'êçà' becoming the letter 'o', resulting in "oYo"; don't fret if you occasionally have a letter that looks like one from our own alphabet -- simple shapes, such as circles, just make sense to be commonplace elsewhere.)
Also consider the writing methods in use at the time in your conlang's history when it was first being written down: A brush and ink could result in sweeping arcs and stylistic calligraphy, whereas chiseling into stone tablets would more likely result in straight lines and stiff characters.
You can use a process like this to come up with histories for each of the letters in your alphabet, or symbols in your syllabary. Or, you can ignore all of this and just create something that you think "looks good": [Nobody knows](http://www.oxforddictionaries.com/us/words/why-is-the-alphabet-arranged-the-way-it-is) why the letters we use are like they are, and even the ordering of our alphabet (excepting some later additions at the end) is a complete mystery. You can always produce different letters from a single basic shape by using rotations and flips (dbpq), repetition (vw, nmg), small additions (OQ, rn) or subtractions (bh, EF), or minor tweaks (kx), any or all of which can help to unify the "style" of your alphabet. You can also follow the examples of ancient languages from our own history, such as simply omitting vowels from your alphabet like the ancient Phoenicians, which can help to make your written language stand apart from one that's simply a shuffled boggle of our own. There's no hard-and-fast rules for doing this, just ideas for how to get there on your own; I've been spending a lot of time myself working on my own conlang, including a unique writing system for it, so this is the culmination of what I've found for myself over the past year (off and on) .
[Answer]
Alphabetic symbols (as opposed to syllablies or ideographs) should be simple and maximally distinct from each other. I've thought of this before, and it’s actually quite challenging to come up with something that’s not an actual letter in some writing system already! Look through the Unicode tables.
Look at what *can* be done in a small box with a few strokes. You can make lines or curves between roughly defined regions within the box. How these intersect or how the endpoints relate to other featues becomes a recognisable aspect. Strokes can be straight, curved, recurved, etc. But evolution will tend to keeping them *simple*.
You might dream up some ornate symbols, but an ancient accountant or merchant would not make such beautiful and precice letters when doing real work. Strokes that are fast and easy (thus minimal) and easy to tell apart when written quickly will be what gets taught to the new guy.
[Answer]
One other thing to consider is *handwriting* (or whatever your species uses in place of hands). For example, compare this
with the same text as you would read it in a book or on this web site. Generally handwriting will tend to link the letters (so that you can write it in one continuous movement), and even modify them in order to easier write them in a linked fashion.
I think it should add a lot of credibility if the written language has a "display text" form (used e.g. on monuments and in books) and a handwritten form, which differ significantly, but are still close enough that you can usually recognize the "display" characters from the handwritten ones, or at least guess how the display characters got changed to their handwritten form (consider e.g. the handwritten "s" which looks quite different from the printed "s", but you can still guess how it got its form starting from the printed one).
[Answer]
First, think of how your culture is writing. The writing material and the kind of writing tools matter a lot; the specific shape of runes (no horizontal strokes) is explained be the fact that those characters are scored in wood; lines parallel to the texture of the wood disappear.
Practice with the writing material and tools, and devise some working character shapes. This is the creative part to enjoy.
For the systematic form of a script, take inspiration from the existing writing systems of the world: The are purely consonantic scripts, full alphabets, sylabaries, and ideographic scripts, also look on the writing systems that Tolkien invented.
[Answer]
I'd recommend taking a list of the possible sounds in the International Phonetic Alphabet. From there, think which sounds are used for this alien race, since only those will have a written representation.
Maybe if some sound happens sometimes but is very rare, or was introduced way after the creation of the writing, it could be represented with small symbols added to a similar letter (like we do now: ç, ä, ê, etc.)
Now that you have the sounds that will require a letter, I'd recommend checking on how the sound is categorized depending how we pronounce them, and use that for creating the letters.
For example, it would make sense that for vowels, they'd use '-', '=' and 'o' depending if the mouth is (almost)closed, mid-opened or full-opened. And depending if the sound is frontal, central or back, put some mark. In the end, for example, sounds for 'i', '…®', 'u' might be 'L', '+', '‚îò'.
Also, for some consonants you might use a symbol representing where that sound comes from. I'm pretty sure the origin of 'S' is not that is the sound a snake does (and S can resemble a snake) but that could be the origin in your language.
] |
[Question]
[
[Western Marches](http://arsludi.lamemage.com/index.php/78/grand-experiments-west-marches) is a style of RPG game where the players face an increasing amount of danger and hazards the further they go in a given direction. This can be due to being on a frontier, on the border of a war or for any other reason. The problem is that this is all fairly contrived. There always seems to be a focal point from which danger spreads. A magical explosion that mutated the land around it, the closer you get, the worse it is. A war on a border, the further you go the more deeply the enemy are entrenched.
I want to know if there any reasons as to why a world would be inherently more dangerous the further you went in a direction (or over time) *without* there being a focal point of danger. Given that worlds are circular, lets set the distance that they can travel to be at least 2000 miles.
While danger and hazards caused by people are fine, I would also like some focus on non man made problems. I *do **not** want answers that have the most danger at a focal point.* The players are never meant to reach that point, so you don't need to worry about hazards and dangers suddenly stopping.
I'm primarily looking at a standard Dungeons and Dragons style setting (although answered based on high tech are welcome, I can use them for different games)
[Answer]
There seem to be three main reasons:
1. They are leaving a focal point of safety. This can by caused by magic, your own forces, inhospitable terrain for the enemy. One useful one would be a massive attack (like meteor strike) where you were protected so the initial foes are weakened. This is, kind of, cheating, however as it is just a focal point of danger for the enemy.
2. General topographical world differences. Imagine the enemy is frost giants and you are a band of amphibious tritons. When you move away from the sea and go towards the poles or up in elevation: you will get weak, they will get stronger, or both. These topographical differences are not focused but certain environments through the world can be beneficial to different sides/foes. This can be magical topography like different magic levels in different regions. This can easily be resource availability if trolls eat Yummirockite and it is located in varying amounts in different regions.
3. Off beaten path effects: California isn't that dangerous any more unless you are LA. It was, however, much more dangerous before it had been explored. If there are many other adventurers who have gone out in your dangerous direction, the further you go in that direction, the more dangerous it will be as few forefighters have left you any metaphorical foot holds. The closest big bads have already been slain; the furthest are still waiting to be discovered.
[Answer]
The approach I took to my own Western Marches world was the combination of two ideas.
First, there was a long-lasting war that has recently ended due to an unexplained disappearance of one side that has, up until that point, mostly been winning -- this left the territory beyond the frontline littered with old battlefields, traps, half-functional war machines, magical anomalies, etc. It would be logical that as the adventurers traversed this "no man's land" and came closer to the disappeared faction's true borders, they would run into increased incidence of automated and passive defenses.
The second idea was one I borrowed from our own history -- namely, the [Migration Period](http://en.wikipedia.org/wiki/Migration_Period). In this particular setting, the two fighting factions were keeping others -- various monstrous races -- bottled up behind a mountain range by controlling the key mountain passes. Once one faction disappeared and the other was too exhausted to reclaim its lands immediately, these races began flooding into these unclaimed territories. Here, the escalation of danger followed the pattern of a given monstrous tribe arriving, settling in, but then being driven out by the arrival of a second, stronger tribe, which in turn would be displaced by an even stronger one, thus creating "natural" difficulty tiers for adventurers as they ventured further from the safety of their forts and frontlines.
Another idea I toyed with in an unrelated campaign was setting the game in the world's subarctic regions. The PCs would need a compelling reason to venture into the wilderness -- a rare resource only obtainable there or the like. However, the closer to the pole they would venture, the more hostile the environment would become, the less sustenance they could find and, concurrently, as conditions became too deadly for regular fauna, it would "logically" give way to magical creatures and other supernatural horrors wandering the eternal ice fields.
[Answer]
While it doesn't fit with the D&D so much, if you had a planet with uneven sun exposure, it could well be the case that as you go further in the direction of the greatest exposure, you come under increasing pressure from the fauna that live there. You can retain or discard the standard day/night cycle or even seasons, based on the direction of travel, without it ever breaking the planet's own internal logic. This works best if the players are in an equatorial region, moving in either direction.
Even without magical creatures, most real world animals are more dangerous if you've not encountered them before. If someone from an arctic region, used to fighting bears and the occasional penguin, were to come into contact with rhinoceri, crocodiles and dropbears, they would have no tactics and knowledge of how to defeat these new and terrifying enemies. Also, the very fact that the animals and people of the adverse climate are adapted to the environment makes them deadly enough.
Secondly, if you're looking to add some less standard play to your game (Ryuutama style), you can have a lot more interaction with the deadly environment itself. Heat exhaustion, thirst, quicksand, blizzards and the like would all be just as deadly as any level appropriate encounter, with the added bonus of total GM control; if the party starts to flail, you can offer reprieve in a much more fluid way than saving them from a poorly-aimed combat encounter.
[Answer]
I would have to support both [kaine](https://worldbuilding.stackexchange.com/users/129/kaine) (point 3) & [Danny Reagan](https://worldbuilding.stackexchange.com/users/539/danny-reagan) (his first paragraph), with a few minor modifications.
The easiest way of explaining why hostile creatures & related conditions, (leaving out the environmental factors of survival), would increase as the characters went farther away from their starting point is:
1. an aggressively hostile world
2. population centers of hostiles
**Hostile World**
Each city or town would have to be cut out of the hostile world (hostile monsters, beings & wildlife killed or run out of the area, traps cleared, etc...).
If a city or town were to be abandoned for some reason the hostile world would eventually reclaim it, (or quickly if a tribe of orcs etc... came to loot & stay).
This is why it should be a fairly hostile world to start with... in the real world this could take a lot longer (until the appropriate habitat developed) additionally there is not near as much in the way of hostile creatures as in a typical fantasy world...
The farther you went away from the town the higher the risk, (towns would fairly naturally be avoided by hostiles as it generally doesn't make sense for them to risk their lives for territory that is defended & patrolled... easier is better in the 'natural' order of things).
**Population Centers**
The other part to this is that, once you get so far out into untamed land, the risk would actually stabilize, with the exception of getting closer to a population center (den/hive/nest/village/etc...) of hostile creatures.
In this case, just as is the case with hostiles getting closer to a 'civilized' town, the risk of running into the specific hostile creatures inhabiting that population center, & the risk that they will be more likely to fight you to the death, increases the closer you get to the center... of the errr population center.
NOTE: This concept still holds true with nations or large groups of hostiles... if there are A LOT of orcs that have defined their territory to be rather large (think of a province or state, or even a country in modern terms), if orcs are generally hostile to the characters, then entering their territory would increase risk & the farther in/closer to actual population centers you got, again, the higher the risk, (provides a means of explaining this on an even more broad scale).
It's my opinion that those two mechanics: a generally/aggressively hostile world, and population centers of hostiles, is enough to explain the increases in a logical enough way that it doesn't feel contrived (assuming that's what you are going for... which it sounds like you are...).
Hope that helps.
[Answer]
1) Probably the most realistic and novel form of "it gets harder the further you go" is to use the historical model i.e. travel and adventure wear you down and you get weaker as you go along.
There are many, many examples in history of armies, expeditions, merchant caravans etc starting out hail and strong and by attrition on the road arriving tattered and staggering barely able to walk.
Normally, the fictional narrative has the characters and the challenges both start out small and grow increasingly power and more dramatic as the story progresses. In reality, the travelers start out strong but after the wear and tear of travel on people, animals and vehicles, fights, accidents disease etc, they get weaker. Challenges they would have brushed aside at the beginning can kill them towards the end.
It's a complete inversion and feels emotionally unsatisfying. In the classic dungeon scenario, it would be like having a boss in the first chamber, with the characters losing xp or levels as they progress (simulating injury) and in the very last room, getting wiped out by a couple of Kobolds. Yeah, it's realistic but we don't play RPGs to experience reality.
2) Changing climate. One earth traveling north or south 2000 miles can take you from mild temperate zones to tropical jungle or freezing polar regions. In either case the going gets harder. In a magical universe, each shifting climate would have it's own creatures or races to battle. As the characters got further and further from their homeland the combination of climate and the unknowns of dealing vastly different life forms, races, magics etc would increase.
There wouldn't be a focal point, just increasing maladaption and functional ignorance.
3) You could have a single enemy that grows in power overtime. E.g. The characters have an enemy who raises up an spirit entity from another realm to kill them. The spirit knows little of the story world so it starts out weak and naive. Each time it tries to kill the characters though, it learns a bit more. As the story progresses, the spirit and it's attacks (direct or via proxies) grow more and more powerful and sophisticated.
You could substitute anything for the spirit entity as long as it learned as interacted with the characters growing more threatening overtime.
The big advantage of this scenario is that its really about changes over time instead of space. You could set it in a travel scenario but you wouldn't have to. The characters could remain in a fixed location and just suffer repeated attacks, each more deadly than the last.
[Answer]
I run a West Marches game on Roll20; I have 20+ players and we play 3-4 times a week using 5e D&D. We are currently on session 43 and going strong.
My answer to the 'why?' concerning zones of danger is to use discontinuous magic; in my game magic is not present everywhere at the same levels. In some places you can only cast level 0 spells and others level 9 spells, with everything in between. Civilisation is always concentrated in the low magic zones because powerful monsters hate going into low magic zones. This is because, for example, that a Dragon cannot fly in a low magic zone because Dragon flight has to be partially magical as no beast that big could possibly fly according to natural law.
This achieves two things: my players can tell roughly how dangerous an adventure is going to be by travelling there and measuring the power of the aura with a Laen Glass; a flask containing a fluid that glows softly in the presence of a magic aura. The intensity and colour tells someone skilled, something about the prevailing aura and its source.
Secondly; the auras mean that adventures in civilised areas become possible because magic can't mess up the scenario any more. No more invisbility or divination to spoil your plans. Now the PCs have to work no matter their level. And it also means that civilised folk have no magic or magical defences and aren't really interested in it; which explains why there are few adventurers.
You might ask about balance issues with spell casters; but if carefully designed, it is just another incentive for players to go further out as they level up; otherwise they can't use their most powerful spells.
[Answer]
Western Marches campaigns that I have seen tend to have a natural border (such as an ocean or mountain range) that provides more linearity to the danger. Such that moving away from the central city (which is snugged up against that border) increases danger, but so does moving away from the border itself. This represents the Western Marches backstory which stipulates that it is a border town of a greater power.
```
++-----------------+
A| |
A| ^ |
A| | |
A| | |
A| | |
A| | |
A| | |
A| C------------> |
A| |
++-----------------+
```
If you want a perfectly radial increase in danger however, consider displacing your city to another, more dangerous, plane. Say a magical cataclysm takes place (hello campaign opener!) and displaces the city of Genericity to the plane of Wyrdnez. The effects of the transport merge a section of the normal plane with Wyrdnez, decreasing in strength the farther you get from the epicenter (Genericity). So the farther you get from the city, the more strange (and dangerous) the world gets, on a smooth gradient. In addition, even when you get past the physical effects of the merge, the natives of Wyrdnez give the area a wide berth, continuing the gradient of challenge past the initial merger.
```
+------------------+
| |
| ^ |
| :|: |
| :.|.: |
| :..+..: |
| <-----+C+------> |
| :..+..: |
| :.|.: |
| :|: |
| v |
| |
+------------------+
```
Over time, the two planes integrate better as the denizens of both acclimate to the change. The challenge could increase over time as the inhabitants of Wyrdnez get organized to try to exterminate the tainted land (Genericity) in their midst.
[Answer]
I can't think of a reason for direction to equate to danger or at least I can't see that being a legitimate reality at all times.
If you have a fortress in which an evil overlord lives and you are trying to topple him, logically yes, it should be more challenging the closer you get.
But you ask about danger, in a direction without the fortress (focal point)...
One thought that comes to mind is a world where good is in one direction, and bad is in the other direction. Maybe "good" armies have fought the "bad" armies up into the mountains. Or how about this scenario. In the west is a mountain range with many active volcanoes.
In the east it is sunny and nice out. (see the sun there) The volcanoes create a constant cloud of ash that the farther west you go completely block out the sun. There is no way for human life to exist there, no crops etc etc etc. Now you just need a set of monsters that require darkness to thrive (or heck even be present). So essentially the farther into the ash cloud, the more dangerous things get. You could even have the ash cloud move east seasonally with winds or something maybe.
In this setting Undead, Drow and other underdark creatures could all be used easily. Been a while since I looked at the monster manual but I am sure you could find others with affinity for darkness.
[Answer]
If you want the danger to be unrelated to geographic location/distance but you still want it to increase over time. Consider something like the wrath of a diety or other sinister power; as the adventurers overcome obstacles the villain sends increasing challenges to thwart his adversaries.
For a more "scientific" approach consider Futurama's take on time travel duplication which is dealt with by physics applying a greater "doom" effect to time duplicated individuals. This effect continues to build up until the doom levels kill off the affected individual.
] |
[Question]
[
Dwarves and their underground cities and the vast network of tunnels that connect them, a stereotype older than Tolkien. What I wonder is how would warfare be waged in this tightly restricted area?
Say there are two sides, one which is numerically superior,the rebels, by a wide margin but has little in the way of training, armor, and melee weapons but does have access to muskets and explosives to combat the other side, the nobles, which do have access to trained and capable infantry that are heavily armored and armed but opposed to the use of muskets for their limited use underground and explosives for the risk of damaging tunnels and vital infrastructure. The rebels have an interest in taking over the nation and ousting the nobles by either exile or execution. Now specifically how would warfare be waged with as little damage done to infrastructures such as tunnels, ventilation shafts, and the pipes that carry water and air throughout the nation? This infrastructure is much more expensive to replace than maintain and the rebels wish to keep as much infrastructure intact as possible because of their interest in running the place after the nobles are defeated.
With this in mind, what strategies could each side employ to either quell the rebellion or oust the nobles with as little damage to infrastructure as possible?
EDIT: Time to clarify how the cities actually are designed and what they look like. and maybe one little fact about my dwarves.
There are multiple cities of various size and their size is three dimensional with multiple tiers and levels instead of being based on a flat plane. An answer immediately resonated to me how best to describe the cities and that would be as geofronts are rather hollowed cavities in the earth. The houses are built out towards the outer edge of the geofront in the form of terraces. There are also large cylindrical walls spaced out in front of the outer edges in which more houses are built in a terraced fashion and there are also streets held by stone pillars which also interconnect them. Think of an onion that has many layers and the area in between these layers act as streets. the closer to the center you get, the wealthier the occupants.
Now onto the tunnels that interconnect these cities. If you've ever played Dragon Age you can get a good idea if you imagine the deep roads. However, unlike the deep roads, these tunnels don't have magma flowing their length on either side and they aren't infested with darkspawn. These tunnels are also shorter and slightly wider and the support pillars are placed in the center and in front of each of these pillars are large illuminating crystals encased in glass that act as giant lanterns which solve the problem of lighting. The tunnels act as a sort of highway between the cities. The dwarves also have manually powered vehicles like bicycles which are used in place of horse-drawn carts which would be the main transportation of goods across cities. little fun fact, the dwarves also have bike races across the length between two cities for rewards of gold and recognition from the public to distract them from their very boring lives.
Now how about the air. Air is pumped in from the surface into large pipes that sprawl throughout the nation, delivering air to the dwarves who live underground. Additionally, water is also pumped from aquifers into a different set of pipes which supplies water to the nation. There are also some cities on the surface which cultivate crops which are brought down to the cities in addition to food imported from trade with humans.
The cities on the surface are a fair bit smaller than those below ground and are where the air is pumped in from. These surface cities are built outside of an entrance to one of the subterranean cities and outside of these surface cities are where crops and animals are cultivated.
I hope this gives a much better idea of the dwarven civilization in my world.
[Answer]
**Normally I would vote to close a question asking for "what tactics..." as too broad or primarily opinion-based... but *subterranean* narrows the question so honking much that I can't justify either condition. Congratulations!**
*Now, on with the answer...*
Let's ignore munitions for a moment. They are so much of a game-changer that they deserve special treatment.
**Condition #1: Choke-point warfare**
Even if the dwarves have widened caves and tunnels into wide areas, there's only so much widening that's practical and expected. And even then, it's not open warfare. That means *no flanking.* This makes warfare brutal and personal.
* Body removal is a huge problem. It won't take long for bodies to seriously congest pathways. Your warring parties would either have treaties in place governing the necessary removal of bodies, or would resort to ambush-tactics when someone starts to remove the bodies. Of course, bodies *decompose,* which means you can't just leave them there. The stench in a restricted system like caves would be *enormous.* Which is very advantageous for whomever is upwind in the cave system. Yuck, but I can actually see a particularly ruthless foe resorting to minor ambush tactics to keep the enemy from clearing the path *just to let the stench roll downwind to sicken the armies & residents in those locations.*
* Even though Tolkein, D&D, and most of the fantasy world tend to depict Dwarves as small, heavily armored tanks, that would be incredibly cumbersome in tight quarters where swinging space-consuming weapons (aka, battle axes) would mean one hopefully-very-tough dude is up front doing 99.9% of the fighting. Now, to be honest, I can see the Dwarves developing a *champion* system not unlike Japanese *bushido* where combat would be frequently between (and decided by) just two combatants. But let's assume everybody's *really torqued* at each other and we need to get more people into the fray. In that case, I'd see a lighter armor fencing-style of combat forming, where damage is caused by quick slashes and thrusts rather than massive two-handed chops or even a dual-light-hammer style (think 4# engineering hammers) where finesse is more important than force-of-impact. If some idiot did come forward wearing thick plate (party pooper), then a simple 4-6 man battering ram would quickly force this dude to the next curve-in-the-cave wall where he would be quickly opened like a can of tuna without the use of a can opener.1
* Gas is your friend! Which means having control of the upwind-side of the passage is a really big deal. Simple "I'll control the passage in an hour!" gasses can be made with sulfer and fire or even just green leaves (smoke is a very practical way of clearing a cave). But what would really reduce your enemy's numbers is to use either an [asphyxiant gas](https://en.wikipedia.org/wiki/Asphyxiant_gas) like natural gas or propane to displace the oxygen in the air or a carbon filter or [stuff like this material](https://phys.org/news/2014-09-material-oxygen-air.html) to remove the oxygen from the air. That'll teach them to stop sending their tribute!
* Finally, to build on Henry's answer, torches and concave reflectors or even optics would become powerful for short-distance blind-thy-enemy tactics. It would be easy enough to retreat a few dozen feet to the next cave turning to avoid the powerful light, and it has the limitation of creating massive contrast (think "shadows are really easy to hide in"), but as a support weapon used to momentarily blind the enemy at the beginning of combat it could be very useful.
**Condition #2: Urban fighting?**
The next question is, how do people actually live in caves? Tolkein liked to portray massive open cities (so to speak), but I doubt that would be the case. Mines are a pain the butt and keeping the roof off the floor is a big part of the problem. Support structures are expensive and require serious planning and engineering.
I suspect that "cities" are more like warrens where "roads" are caves with living quarters carved into the walls along the caves or tunnels. Each home becomes an ambush point, but the basic fighting style wouldn't change. Therefore, no "urban fighting." It's all still choke-point fighting.
* However, this means that gas and/or smoke becomes really important to clear out rooms/houses/complexes. Places that might not have a second entrance/exit/access point. You should be thinking "smoke bomb" and "tear gas." Note that the possibility of war may force the construction style to have *back doors* in many "buildings" (a group of rooms used for a specific purpose, whether a family dwelling, a government office building, or a factory). Those *back doors* would empty into, perhaps, small tunnels like alleys that would also serve as escape and/or ambush access if the enemy got into the ~~warren~~ city.
*Note that as I write this, "upwind control" is becoming a bigger and bigger issue. Just like we on the surface wanting to control the top of a hill or ridge, the army that controls "upwind" controls the battlefield. The ability to **shift** the direction of windflow would be a huge benefit for an army... and a city. Indeed, you would ideally want the ability to over-pressurize your "city" such that you become "upwind" to all tunnels existing your city. Hmmmm... He who has the biggest surface-to-city air pumps has serious combat control. Which means that a ton of your fighting might not be subterranean as control of those surface-to-city pumps (either the pumps themselves or the surface access points) would be massively strategic. Dang.*
**Condition #3: Munitions**
OK, firearms in tunnels aren't as useful as they might seem. Yes, they'd kill the enemy quickly, filling the tunnel with bodies quickly, and filling it with smoke quickly, which affects both sides alike quickly... frankly, they'd be more of a pain in the tuckus than anything else, especially since their biggest value (range) is of little use in tunnels and caves.
Black powder as a smoke-causing substance is more useful, but only to the upwind people.
What's really useful, though, is *explosives.*
* Collapsing a tunnel, either to block the advance of a foe or to protect your retreat is useful, if somewhat permanent.
* Creating a *new tunnel* quickly to "flank" the enemy... now *that's* useful.
* Diverting water into the path of an enemy... that's *very* useful. Better still, unlike collapsing the tunnel/cavern, it's *temporary.* You can collapse access to the waterflow (theoretically) and recover the tunnel (after you've flushed your enemy from it, of course).
So, explosives good. Firearms bad. Black powder OK.
*Of course, building on the torch-with-a-concave-reflector idea is **flash powder.** The ability to create a really bright burst of light that only affects the enemy is very good. Oh, yes... very good! The evil, vile papparazzi ([ptui!](https://www.youtube.com/watch?v=cwm57lJRNQU&feature=youtu.be&t=7)) might have a use after all.*
---
1 *We've all had that experience, right? Where all you have is the meat-tenderizing hammer and a butter knife... but you just* have *to have that stinking can of tuna? Sure you have! I can't be the only one.*
[Answer]
**Air is life.**
[](https://i.stack.imgur.com/0kGst.jpg)
[Georgius Agricola, De Re Metallica, Ventilation of Mines, 16th Century](https://www.sciencesource.com/archive/De-Re-Metallica--Ventilation-of-Mines--16th-Century-SS2505828.html#/SearchResult&ITEMID=SS2505828)
In stories of underground civilization, short shrift is given to ventilation. But ventilation is paramount if you are working or living underground. This is best laid out in the history of mining and working in deep mines. Gases coming up from below can be poisonous, or explosive, or kill by excluding oxygen. Your own efforts can consume the oxygen, especially if you have fires. The illustration shows various methods for getting air exchange down into a mine including bellows, pumps. One could also have a shaft in which there is a fire to produce an up current and a separate shaft to allow ingress of fresh air. Read more - <https://web.mst.edu/~tien/218/218-VentHistory.pdf>
In any case, fresh air is the life blood of any underground endeavor. There will be connections to the surface for ventilation (as stated in the question) and control of these will be control of the underground empire.
<https://web.mst.edu/~tien/218/218-VentHistory.pdf>
[Answer]
### It depends on the size of your nation and its cities
The answers by [Wilk](https://worldbuilding.stackexchange.com/a/129220/56286) and [JBH](https://worldbuilding.stackexchange.com/a/129222/56286) are very detailed and quite accurate under certain assumptions. And that is that your cities are "small" and the entire infrastructure is primarily composed of small tunnels large enough to allow your mining equipment to be transported (or perhaps a little bit larger than that).
Reading your question again made me think that you might be envisioning a network of [Geofronts](https://www.urbandictionary.com/define.php?term=Geofront)([2](https://evangelion.wikia.com/wiki/GeoFront)) each connected to others via various tunnels that would act as highways between them. These, of course, would be huge feats of engineering that would take years of development and planning but let's assume that the Dwarven Empire can boast of being able to build such grand structures at the height of their power. We can also assume that such meticulous planning also involved solving the issues of ventilation with multiple redundant air shafts and "greenery". (That these shafts would be huge and/or porous and that the greenery would need to thrive in low-light conditions is a separate topic of discussion. There are ways to prevent outside intruders in these cases that are also beyond the scope of the question.)
**So, what kind of warfare might be feasible in this kind of environment?** Overall, [**Urban Warfare**](https://en.wikipedia.org/wiki/Urban_warfare) would dictate most combat conditions in this kind of superstructure. There would be two kinds of battles that each side would have to wage: tunnel battles and city battles. **Tunnel battles** would involve fighting for control of tunnels, both their entry and relay points ("villages" present between cities) and would most likely resemble JBH's choke-point warfare. This depends a lot on the width of the tunnel. (A "Mega tunnel" would be less of a choke point and more of a front.) Keep in mind that sealing tunnels, bypassing and/or building new tunnels might be commonly employed tactics, especially to avoid the dangerous ventilation and choke point issues. Dwarves are master tunnelers after all!
**City warfare** would resemble traditional urban warfare. Here, an attacking force would be trying to take control of an entire city and its infrastructure and use that city as a staging point to attack the next city or cities (tunnel warfare again). As wikipedia states:
>
> Fighting in urban areas negates the advantages that one side may have
> over the other in armour, heavy artillery, or air support.
>
>
>
There would be no air support here, but heavy artillery (c. 18th century canons) can be employed by either side. This section summarizes the usual conditions encountered in urban warfare:
>
> Tactics are complicated
> by a three-dimensional environment, limited fields of view and fire
> because of buildings, enhanced concealment and cover for defenders,
> below-ground infrastructure, and the ease of placement of booby traps
> and snipers.[citation needed]
>
>
>
Another thing to consider is the effect on civilians regardless of alignment:
>
> Some civilians may be difficult to distinguish from combatants such as
> armed militias and gangs, and particularly individuals who are simply
> trying to protect their homes from attackers.
>
>
>
**A caveat**: If you only have a single mega city then the scenario is slightly different. Instead of island hopping, you may have urban warfare for those vying for control of the city (rebels), and tunnel warfare for those vying for control of the surrounding mines (nobles). Since the rebels would be commoners and numerically superior, they would already have influence in both the mines and the city slums.
To summarize (**TL;DR**):
* If your cities and nations are "small" and are mainly structured around narrow tunnels then ventilation control and choke point warfare will be an army's main tools.
* If your cities are "huge" then more traditional urban warfare methods would be employed coupled with tunnel warfare when "city hopping".
**EDIT:** Based on the question's recent edits, I don't think my response would change much. The only difference I can spot is that the ventilation shafts/surface cities could now be used as ingress points into the city. Dwarves that usually preferred to use tunnels to cross cities, might find it tactically advantageous to use the surface to reach other cities!
[Answer]
Light, or more accurately, the ability to operate in the absence of light is the great strategic advantage that the rebel workers have over the nobles and their trained militia. The militia was trained to handle combat with other nations, out in the daylight, above ground. Meanwhile, the working class, who became the rebels have been living in the caves for their entire lives. They are intimately familiar with their battleground and the intricacies of working in the absence of light.
[Answer]
You can quell the rebellion by showing that you control the air supply. Deploy a gas that is too heavy to go very far (and temporarily block off some key shafts to keep it from spreading), or maybe a powder, and that has no adverse effects beyond making the people who breathe it horribly ill for a few hours (vomiting, diarrhea, etc...). If you want them to remember this every time they use those tunnels, make it fast acting so the place reeks. If you need to use those tunnels later, then make it delayed acting so they get ill at home (as long as they know you caused it).
The rebels might also be able to do this to the nobles but it depends on how concentrated they are. I'm guessing they have larger homes and more space in general. But you could hit an entertainment or shopping venue that only the rich attend. This won't hit them where they live though, like what the nobles can do to the rebels.
[Answer]
Weapons we can actually look at WW1&2 trench and tunnel warfare for ideas not to mention the countless other times tunnel fighting has popped up in [history](https://en.wikipedia.org/wiki/Tunnel_warfare).
Counterintuitively for dwarves axes make for really poor choices for underground combat, basically anything you have to swing is bad since you often won't have the space. Short swords, short spears and other compact stabbing weapons are good choices, their motions are compact and direct. Likewise small shields are better than large ones. Basically any weapon you could not use in a closet is a poor choice.
Crossbows are just about the only ranged weapon that works since they also do not need much room. Guns can share this feature but you need to keep them short, long muskets become unwieldy and impossible to load. Shortguns like pistols and blunderbuss are usable however. Note however that ranged combat is limited, usually you will only get one shot unless you have long corridors. Builder might design these at defensive choke points to make it as hard as possible for attackers. Some old fortresses were designed with saw tooth or right angle expansion walls so defenders had cover and attackers did not.
] |
[Question]
[
In Science Fiction we often see the protagonists exploring all sorts of strange new worlds with no apparent discomfort to the variations in gravity.
What factors determine how strong the gravity will be on a planet? Is it purely based on the size of the planet in question or are other factors like core density involved?
In short: is it possible for a human to walk on the surface of a planet which is a thousand times the size of the earth without being crushed?
[Answer]
Only two factors impact gravity: **mass** and **size**. Alternatively, **density** and **size** (since density is mass divided by volume, a measurement of size).
The bigger the mass, the stronger the gravity. This is direct and unavoidable.
The bigger the size for a given mass, the smaller the gravity, since you are farther from the center of mass (the center of the planet). But this is not so important since habitable plantes (those with a solid rocky surface) have quite a reduced span of available densities.
Besides, you can think on external effects. Since your question do not have tags about "hard science" or "fantasy", you can say that there are no external factors (hard science), some natural factors like a dense atmosphere that causes some floating like in water or the rapid spinning Tim B. has proposed in his answer (sci-fi, but note these does not truly changes gravity) or there are magic minerals with antigravity capabilities like [Cavorite](http://en.wikipedia.org/wiki/The_First_Men_in_the_Moon) (fantasy).
Also, gravity pulling from an external body causes variations on gravity (tides), but you can see here on Earth how much you notice them.
[Answer]
Envite covered most things, but to answer the specific question:
>
> In short is it possible a human could walk on the surface of a planet
> which is a thousand times the size of the earth without being crushed?
>
>
>
Not with any known natural planetary body. The density of the planet would need to be far lower than any known material for this to be possible.
An artificial structure might be able to do this (for example a hollow sphere you walk around on). Alternatively the use of technology would allow this if anti-gravity fields of some kind were available.
One last option might be a planet with an extremely rapid spin. You could land on the equator and centripetal effect (the spin of the planet throwing you off) would counteract some of the gravity. Get the balance right and it would be survivable, the planet would be an odd shape though (very flattened) and have some wicked weather systems. There's an old-school hard sci-fi novel called "Mission of Gravity" set on just such a world although from what I remember even there it wasn't as extreme in size as you are suggesting.
[Answer]
Three more effects to compliment the previous answers:
1. **Shape** - If a planet somehow obtained a non-spherical shape during its formation, gravity would undoubtedly vary over its surface. This is even [true for earth](http://en.wikipedia.org/wiki/Gravity_of_Earth#Mathematical_models). You can imagine that if a planet was even more oblong than earth variations in gravity at different points on the surface would increase. This would also have a great effect on the different species which could inhabit different parts of the planet if it supported life. Also note that for an oblong planet, the *direction* of the gravity vector will not always be perpendicular the surface of the planet.
2. **[Terrain Elevation](http://en.wikipedia.org/wiki/Gravity_of_Earth#Altitude)** must also be considered, whose effects are similar to variations in the planet's shape.
3. **Density Variation** - There will also be gravitational variations if there is a non-uniform density distribution (I'm talking about variations over the [azimuthal or polar](http://en.wikipedia.org/wiki/Spherical_coordinate_system) angles, not just radial variations). Remember that for free body diagram style analyses the gravity vector will always point towards the center of mass (COM) of the planet, which is likely not the centroid of the shape if there is a non-uniform density distribution. Also keep in mind that the center of mass is also the center of rotation for the planet, so if you have a spherical planet where the COM and the centroid are not co-incident there will be a noticeable eccentricity in any rotation it has.
[The Space Trilogy](http://en.wikipedia.org/wiki/The_Space_Trilogy) by CS Lewis (Author of The Chronicles of Narnia) describes an interplanetary adventure where some gravitational effects are discussed. It's also a good read :).
[Answer]
Answers:
1 & 2: (previously answered) the Planet's mass and your distance from the center of that mass (usually also known as the planet's radius - but it isn't in all cases).
3: **NO** A person could not walk around on any planet 1000x the size of Earth given what we know about planets.
**However**, in another answer [I calculated that under *very special circumstances*, a person could walk on a planet 1000x the Earth's mass and 10x its diameter](https://worldbuilding.stackexchange.com/questions/15062/stumped-how-can-i-get-a-huge-earth-like-planet/15076#15076).
The very special circumstances would be a world rotating so fast, it is almost ready to break apart. It would generate a huge equatorial bulge. The addition of that bulge placing you further from the center of mass and the centripetal acceleration would enable a person to walk on a planet up to about Jupiter's mass ($ 1000 \times$ that of Earth's).
The density that goes with this number indicates that such a planet would need to be almost entirely made of water or lighter elements - so you might not find a surface.
Of course, specifying smaller planets makes it easier to find a combination that would enable humans to walk around.
[Answer]
Here is an easy formula to determine surface gravity of a planet relative to the Earth. All you need is to know your "planet" in Earth masses and Earth radii. Then the surface gravity relative to Earth would be $M/R^2$.
I couldn't find a reason why you can't "build" a "rocky planet" as big as you want, but nature maxes out at about 20 Earth masses (The heaviest found so far has been Kepler 10c at about 17.2 Earth masses.) Even Kepler 10c is only estimated to be 2.3 Earth Radii so this gives a surface gravity of 3.2g.
Other examples would be Gliese 1214b (our best candidate so far for a "waterworld"/ low density). At 6.55 M(Earth) and 2.68 R(Earth), it's surface gravity would be 0.91g.
If you don't mind "floating" in an atmosphere, you could live on the "surface" of Jupiter (where atmospheric pressure is about 1 bar) and weigh 2.5g.
Another interesting prospect would be "floating" on the surface of a "cold" brown dwarf where atmospheric pressure and temperature would be Earthlike. If you take an example of a 12 M(Jupiter)/ 1 R(Jupiter) dwarf you woudl have a surface gravity of about 30g.
] |
[Question]
[
**Post-apocalyptic scenario:**
What would be the minimum number of cities (financial/transport hubs, e.g. New York, London, Beijing etc) that need to be taken out by nuclear weapons or other means which would create enough disruption to the world economies that trade shuts down and throws first world countries into anarchy and an every-man-for-himself situation, even in countries that do not necessarily get hit badly, if at all, e.g. Australia/Africa/South America (I have read other answers that state that these would be the least likely to be hit by nuclear weapons if there was a nuclear war.)?
Also, how long would the breakdown in each of these countries take, like the loss of essential infrastructure, electricity, sewerage etc., leading to the every-man-for-himself situation?
[Answer]
## One - aka the problem with Nuclear War
Wait? Just one? Yeah, just one. Because more than one would end in total collapse of the world as we know it. And just one can lead to big economical collapse.
**Who attacks whom?** As you did not provide any background, I am assuming that we are playing with actual world. So, best attacker to cause "just" economical collapse is North Korea. Any other attackers would lead to Nuclear World War III, in my opinion.
And even North Korea can lead to that scenario too. But lets see scenario where we cause "only" economical slowdown.
1. North Korea launches nuclear rocket to Shanghai, China and manages to destroy it and make unsuitable for living due to radioactivity. According to [this site](http://www.worldshipping.org/about-the-industry/global-trade/top-50-world-container-ports) it is the world's largest cargo ship port.
2. The [Security Council of the United Nations](https://en.wikipedia.org/wiki/United_Nations_Security_Council#Permanent_members) agrees on joint attack on North Korea
3. North Korea regime falls, [about 20 million people](https://en.wikipedia.org/wiki/North_Korea#Society) now need to be taken care of.
4. South Korea, China and Russia (bordering countries of North Korea) are barred by influx of refugees.
In nutshell: China struggles economically because it cannot ship as much goods as they could and also they have to take care of immigrants.
Stock prices fall, world economy is in biggest recession as we know. it will take about a decade to get back on track...
**Note:** I did not collapse the entire economy, I just caused total recession of world economy. If you want total collapse, be prepared for total collapse of all humankind
[Answer]
# 11 nukes
Nuke these cities with 50 megaton surface blasts:
* Amsterdam
* Dublin
* Frankfurt
* Hong Kong
* London
* New York City
* Paris
* Seoul
* Singapore
* Toronto
* Zürich
This list is based on the assumption that all of the world's economies are highly interconnected and that instant illiquidity in one market will have immediate and highly destructive effects across all markets.
Since the Internet will still be largely functional, the world will know very quickly what happened. Mass panic in many metropolitan areas will ensue as no one has any idea if the attacks were a one-time thing or just the first phase. Expect mass exodus' from metropolitan areas as hundreds of millions of people attempt to flee potential target areas. This is a humanitarian crises of unprecedented proportions. No disaster management agency on the planet can handle that kind of scale. Fights over food, shelter and supplies will quickly turn deadly.
**Panic is what kills people. Panic is what will rip the world apart.**
The fallout from these weapons will irradiate much of Europe. Assuming a uniform wind from the south west, radiation levels of at least 1 rad/hour will reach Berlin, Prague, Munich, Hamburg, Edinburgh, and Boston. These cities are effected based on very very simple wind patterns. The actual fallout paths may be more or less widespread.
Note that The Hague isn't directly hit but it is inside the thermal blast radius where 3rd degree burns happen to all exposed flesh. If the winds are right, fallout rates of 100 rads/hour will fall on Shezhen and Donguan. Macau is also in the thermal blast radius for 2nd degree burns.
All told, approximately 41 million people have died with an additional 26 million injured. This does not include fatalities or injuries sustained from fall out.
Anyone who cares to look at a simulation of this attack may refer to this [NUKEMAP](http://nuclearsecrecy.com/nukemap/?t=b0cde81384adb9cf41962c9bb4cb2303).
Depending on how the records are kept, the destruction of all these markets will mean that ownership of trillions of dollars of assets can't be guaranteed or quickly verified. Stock ownership is certified by physical certificates which may or may not be destroyed when the markets are. Uncertainly like this has a high likelihood of inducing panic in investors who will want to get cash as quickly as possible. However, the markets are the only place to convert an asset to cash but the markets don't exist anymore. All across the world, investors who get news of the attacks will have no way of knowing when or where the next attacks will happen. They will try to convert whatever assets they have to cash since cash is the most flexible asset to use in emergencies. Some, perhaps many, people will keep their heads and not sell off all their assets but *enough people will panic that it causes market crashes everywhere*. "Circuit breaker" mechanisms in the surviving markets will halt trading to prevent the markets from crashing further.
Even though the Chinese and Japanese markets are still functioning, the local traders are well aware that their economic livelihoods depends greatly on the US economy which is now in tatters. The value of exports from Chinese and Japanese companies will decrease considerably because of the increased uncertainty concerning future demand. Without demand for products, factory managers everywhere will reduce the hours or outright lay-off many workers. The reduction in spending power of all these workers will hurt the local economies, further deepening the growing recession.
In these attacks, the offices of many companies will be destroyed, along with the people who run those offices. As of 2005, 602 headquarters operated from New York City. 40 of the *Fortune 500* companies are headquartered in NYC. A company can survive the loss of its entire C-suite executives but it will take months to regroup and restart operations. Paris hosts the headquarters of 33 Fortune Global 500 companies. All those companies will need to find new headquarters or somehow restore HQ operations rapidly.
Destroying New York will remove approximately [\$1.33 trillion dollars](http://www.cbpp.org/research/economy/chart-book-the-legacy-of-the-great-recession) or 7% from the US economy. This is equivalent to the loss in GDP from the [Great Recession](http://www.cbpp.org/research/economy/chart-book-the-legacy-of-the-great-recession) except it's a permanent loss. London's economy is [\$546 billion dollars](https://en.wikipedia.org/wiki/Economy_of_London) or 18% of the UK economy. Paris' economy is [\$792 billion dollars](https://en.wikipedia.org/wiki/Economy_of_Paris) or ~27% of the French economy. This list could go on but you get the idea. The destruction of the global market cities not only instantaneously destroys significant fractions of each country's economy but it also removes that countries capacity to rebound quickly because of the loss of highly educated workers. New York, London, Paris and Zurich, and presumably *all* global financial centers have services-based economies. All companies outside the attack areas who previously relied on services provided in the destroyed areas must bring those services back in-house or must do without. This has profound effects on corporate profitability in many industries.
In the case of Amsterdam, Paris, London, Dublin, and Seoul the center of government for the respective country has been destroyed. All of those countries will have greatly reduced ability to recover from the attacks.
Humanity will eventually recover but it will take decades.
[Answer]
Zero--you don't need to take out a city to take out the world economy.
You'll need three bombs, each very large, each mounted on a rocket that can deliver them high in the stratosphere. (If you want to pull this totally by surprise you put them in orbit.)
Detonate one over the US, one over Europe and one over the Hong Kong/China/Japan area. Each will kill basically all electronics to the horizon--and from that sort of altitude the horizon is very far indeed.
[Answer]
That is a very difficult question because law and order is not enforced at the point of a gun. Consider the [2011 riots in England](https://en.wikipedia.org/wiki/2011_England_riots) or [uprising in Libya](https://en.wikipedia.org/wiki/Libyan_Civil_War_%282011%29#Anti-Gaddafi_movement) the same year. In both cases, the security forces were unable to cope. But most people in the UK agreed that having something like the present political system was better than anarchy, and a few cops could go back to chasing a few criminals because the riots stopped.
So the question would be "how many strikes until the average Joe on the street **believes** that food will run out and starts looting" and not "how many strikes until the food delivery system breaks down?"
I guess your story would have to hit several major hubs in the the US and China, and perhaps one each in Europe and Japan. That would lead to widespread panic. As side effects ripple through the economy, some people would start hoarding food and the government introduces rationing. They're not well prepared for that and the rationing causes even more panic.
As to how long, perhaps three days? Any longer and people start to think about what they're doing again. Much depends on the public information campaign by the governments in the hours after the strike.
[Answer]
Striking the financial hubs would create chaos and a great deal of secondary and tertiary deaths as systems shut down, but the closing of international financial markets would not, in of themselves, create the conditions desired.
The closing of information hubs (the financial markets) would not stop regional economies from functioning, nor would they have a lot of "real world" impact outside of the blast zones. To create a fully apocalyptic scenario, the physical transport hubs would also have to be targeted. In many nations, this is often the capital city (especially in nations that were created out of older Imperial systems, where transportation was deliberately run to the capital to ensure control and allow the dispatching of troops to quell rebellions). Major sea ports would also need to be targeted, since there would be a major stockpile of goods in and around the port, not to mention reservoirs of fuel and skilled technical personnel who could assist in the rebuilding of society.
To be even more complete, targeting of electrical and energy infrastructure would also be needed; major generating stations (thermal, nuclear and hydro), as well as oil refineries and terminals. For the nuclear planner, there can be some economy of effort since sea ports like Rotterdam or Galveston are also oil hubs with terminals, refineries and storage facilities.
So while 11 cities might be a minimum to induce chaos and disrupt the international market, there would actually need to be several hundred weapons deployed across the globe to totally end human technological civilization. The exact details will require knowledge of the circumstances of the war, who is fighting and what the strategic goals of the combatants were prior to the start (modern nuclear war theory seems to emphasize destroying enemy nuclear capability rather than enemy cities).
[Answer]
## Trigger World War III.
The existing answers all postulate a large number of nuclear strikes required to completely bring down world trade. However, it is not necessary to launch such a large number of nuclear weapons in order to take out world trade.
With war comes the customary blockades and embargoes, which will quickly result in collapse of world trade.
To that end, only one nuclear launch needs to be engineered - A strike on Tel Aviv, Israel, that is launched from Syrian territory. Since NATO and Russia are on opposing sides of the [Syrian Civil War](https://en.wikipedia.org/wiki/Syrian_Civil_War), this creates a natural rift between the two ex-Cold War enemies.
This would lead to Israel activating its [Samson Option](https://en.wikipedia.org/wiki/Samson_Option#Authors.27_opinions), resulting in nuclear strikes over major European capitals. The resultant NATO - Russia conflict would quickly evolve into a nuclear World War III.
[Answer]
**None** or **All**
Economies (of whatever scale) tend to start out as a de-linked systems of arbitrary trade, and slowly knit themselves together through various political contrivances. The scale of economics is determined by the same things that dictate the effective scale of war: logistics technology and geography. Today we can *generally* trade anywhere in the world, but that does not mean that every part of the world is inherently linked into a single economy consistent with the image politicians and media hope to evoke with the phrase "global economy" -- and most serious economists don't discuss things in those terms unless they are trying to popularize an idea.
**Coupling**
Decoupled, per-trade voluntary linkage is mutually beneficial (as per the goals of the participants, hence "voluntary") and ever changing, based on the various motives of the actors in the system itself. This explanation, however, does *not* define a system in the sense that nothing is pre-planned by any central authority -- it merely details a very consistent phenomenon. This is not really "linkage" because the success or failure of each venture is local to that venture (and particularly not "linkage by success" as the criteria of success are determined by the participants only, so "success" is a concept that can only ever be invisible to any central planning authority).
Fully coupled linkage by subsidy + protectionism is linking by failure and almost entirely static. Ventures deemed successful are drawn from while unsuccessful ventures are given to (very broadly speaking), so success criteria is an arbitrary determination made by a central authority (not tied to the actual trade goals of the actors making the initiating decisions) and forced linkage exists to support failures instead of promote successes. Incredibly, this is always done with the intent of *avoiding* massive crashes, but it is a one-way flow and predicts a single point of mass failure eventually. Postponing minor crashes at the expense of general success eventually adds up to pulling dead weight, and leads to a single massive crash. As far as I can tell throughout history these systems have always operated as a ratchet -- the only time this sort of linkage gets dialed back is when a major crash or war (often with a civil war component) occurs and winds up effectively resetting property rights and the legislative record of at least some of the locales involved.
**Robustness**
In a de-coupled state the loss of any set of cities would not destroy the entire economy, because the definition of "entire economy" only includes the set of active parties. The active set shrinking or growing can be a difficulty or a merit depending on who is being asked when, but such a system is extremely robust to *total* failure.
In a fully coupled state the economy will always tend toward an eventual total crash on its own without any cities being destroyed. When infrastructure is centrally administered and certain goods (like food) are price-fixed out of legal profitability the only real market becomes the black market (which may thrive in a crash), and the "official" economy can completely disappear for a time.
**But People are AMAZING -- never underestimate them**
Human history is replete with examples of how adept people are at recovering from unbelievable catastrophes in *profoundly* short timeframes (far less than a lifetime -- sometimes less than a quarter!). This sort of reaction to hardship is amazing. Once the hardship is over, though, the second amazing thing happens: *most* people forget what caused the last crash and double-down on the same problematic system of enforced couplings. It seems that very often this is because the majority of people never knew what was really going on just before the crash (had they seen it coming, they would have reacted differently) and just believe the prevailing rhetoric that existed at the time of the last crash, and assimilate that into their new worldview (if they even develop a new worldview). The few who were able to react successfully to exploit the crisis often wind up becoming a new force within the next political system at some point, and at that point suddenly they find it in their interest to promote the same fallacies for political reasons, and government and industry suddenly wind up in protectionist collusion once again, and the cycle repeats. (I don't think there is actually any solution to this: humans simply seem prone to bust cycles.)
Consider that some of the speculative scenarios in other answers predict a total economic collapse if, say, electronic devices are rendered generally inoperable (specifically, communications networks -- a surprising number of electronics are actually well shielded today). The day the internet dies is the day I start open a caravan trading business specializing in basic grocery needs, and sidelining in electronic and mechanical repair. I (and anyone else who wises up to the change in the nature of value indexing and information propagation) will be wildly successful. That's a hiccup, not the end of the economy. That sort of crisis is an opportunity, not a failure -- this is a mindset, not an absolute.
So how many cities? All, none, some -- it depends on what the circumstance is at the moment, and *in any case* the day after the world economy crashes is the birthday of the new unofficial economy. "The economy is dead; Long live the economy!" People fight, claim stuff, negotiate and trade, its just what they do.
[Answer]
## One. Even without extrapolating into a war.
Nuke Shanghai which is China's largest industrial city, and the world ends.
No nation that is a "serious player" in world economy can do without products manufactured in and around Shanghai. No other place could jump in as an instant or short-term replacement.
[Answer]
Interestingly, you wouldn't need to bomb down and destroy whole cities with innocent civilians. Bombing down certain banks to the ground would effectively throw the world in such economic chaos that is beyond the imagination of anyone. The world trade **will** re-establish, but it would be after a LOT of confusion, disagreements, warring and chaos.
1- [Industrial & Commercial Bank Of China](https://en.wikipedia.org/wiki/Industrial_and_Commercial_Bank_of_China)
2- [HSBC Holdings](https://en.wikipedia.org/wiki/HSBC_Holdings)
3- [BNP Paribas](https://en.wikipedia.org/wiki/BNP_Paribas)
4- Headquarters of [Federal Reserve System](https://en.wikipedia.org/wiki/Federal_Reserve_System)
5- [Bank Of America](https://en.wikipedia.org/wiki/Bank_of_America)
Once you have successfully obliterated their data centers and board of directors, you can be certain that the world trade would take at least several years to return to normal/present levels again.
These are some of the top banks of the world (except Federal Reserve, which is basically a printing press of sorts) and here you would find bank accounts for monsters like Sony, Apple, Lockheed Martin, Samsung etc etc. Wiping out their boards of directors and the data centers (make sure you destroy any and all backup systems too) would ensue a terrible economic chaos which would immediately turn dangerously political, too. Either a lot of countries would be pushing out a lot of warships in the seas or there would be a confusion of accounts and debt record which will drown and muddle all world trade.
A litigation explosion would immediately ensue with banks suing the companies which have now refused to repay their debts (as all records are destroyed). A lot of assassinations and information leaks would occur during this period. Several international corporations would cease to exist altogether while others would gain even stronger hold.
If a world war does not begin immediately, it would be fun to see such a scenario.
[Answer]
I'm going to question the "anarchy" outcome, especially "every man for himself". Assume a worst case scenario where all the nuclear powers are destroyed to the extent that they are taken out of world trade: North America, Europe, Russia, Israel, India, Pakistan. Add to the list South Korea and Japan. That leaves us with your list of Australia/South America/Africa, plus various countries across the caucasus, middle east, and far east.
The big problem is that the global oil distribution economy lies in ruins. Perhaps OPEC have survived, but you can't pay in dollars or euros any more. Alternative arrangements would have to be made. Petrol rationing would probably apply to most of the world. Tourism-based economies face immediate problems.
Other than that, the decay is gradual as things break down and can't be replaced, rather than immediate collapse. Perhaps local wars break out, or local riots about the state of the economy - but that's already a problem in Africa. Places that already have effective government would institute rationing. Places that don't are already run on a hyper-local basis and tend to be less linked into the global trade system. The more rural you go, the longer it will take for people to start to feel the effects of the war.
It would look more like international development in reverse, or Greece-style political dysfunction, rather than "every man for himself". There's always a local strongarm group willing to restore order.
[Answer]
If you take out entire currencies, surprisingly little happens. Hyperinflation and the like happened many times and while it has effects, historically it does not lead to an every man for himself situation.
If you take out all the markets, that means people don't know what the currency of the respective markets is worth anymore. People will fall back on trading product for product, or precious metals like silver and gold. You'd be surprised how many people have a stash of silver in their backyard for just that reason - it's obvious why they don't advertise that fact.
People will still want food and other people still have food which will rot if they can't trade it, so they will find a way to trade.
Equally, if you take out all capitals, districts will still work on their own. Ask any Texan if Texas will work fine without Washington.
Nukes can't kill trade. The one thing that can hurt trade the most is fear. **Use your nukes to create fear**.
* Fear of being nuked: nuke random cities at random time intervals, for months if not years. People will flee from the city which is a huge problem for trades.
* Fear of starving: Nuke large grain stores, right after the harvest.
In any case you need loads of nukes, dozens if not hundreds.
] |
[Question]
[
It's a very old scenario but never seems to be explored in great detail - not even in the Bible.
Two astronauts, a man and a woman, return to Earth to find that all mammals have been wiped out by a virus.
All dead bodies have been cleaned by vultures, insects and bacteria. There is no danger from pollution or from wild beasts.
There is plenty of food to be found in supermarkets and all the basic tools needed to start again can be found.
The pair decide to repopulate the Earth. That's fine, they start and by chance they have two sons and two daughters. But then what? All sperm and egg banks have long been out of action. Their only way forward is incest.
**Question**
How do they proceed? Who should pair with whom and in what order? You can assume that they go ahead in the most practical and beneficial way so as to make the best possible life for their descendants.
In the early days, what scientifically based marriage rules should they put in place to avoid genetic defects as much as possible? What other factors, if any, do they need to address that are specifically related to interbreeding between close relatives?
Scientifically speaking will there be sufficient genetic diversity for the human race to survive?
**Additional - Religious implications**
If the pair believe in Biblical teachings, which Bible passages might they use to justify their actions? Or, in order to stick with their faith, would they simply have to let the human race die out? Similarly, if they belonged to other religions of the world, what accommodation would they have to make?
[Answer]
The population will not be healthy, but it will be capable of surviving as long as they produce enough offspring. Based on the genetics of the 2 founders, a certain percentage of all offspring produced by their descendants will die before reaching reproductive age or be infertile or otherwise disabled. We'll get in to how to calculate that percentage below, but the important concept is that a certain fraction of their descendants **will** be healthy. As long as reproductive rates are high enough to produce enough healthy individuals to expand the population, then the population will continue to grow and the rates of genetic disorders will decrease as they are negatively selected against.
Before we get into the math we need to understand why inbreeding causes problems. You may have an idea in your head like "the loss of genetic diversity", but that's really a nebulous concept that doesn't really matter. The real issue caused by inbreeding is an increase in homozygosity. Humans are diploid meaning we have two copies of each of our chromosomes, (except of course for males and their sex chromosomes) one set from each of our parents. Your chromosomes, while nearly identical, still have lots of differences between them. These different variants are called "alleles". Homozygosity means having two copies of the same allele at a given location in the genome, or put another way, your two chromosomes having the same sequence at a given location. Now, homozygosity itself isn't bad, there's nothing inherently wrong with having the same DNA sequence on both sets of chromosomes. The problem arises when you take into account mutations. Mutations can sometimes break things very badly. If they change the wrong base they can completely knockout an essential gene. Fortunately, since we have two copies of our entire genome on our two sets of chromosomes, even if a mutation breaks one copy of a gene we have another copy that still works and can compensate for it. This is called haplosufficiency. Unfortunately, this means most people carry these lethal alleles, because as long as they are compensated with a functioning copy they don't harm us and so aren't selected against. These bad alleles are known as recessively lethal.
Now we can see why homozygosity is an issue. If an individual has an increased chance of getting two copies of the same allele, then that person also has an increased chance of getting two broken copies of an allele and dying!
Finally we can get to calculating how much of the population will be affected by the genetic disorders. It all depends on how many recessive lethal mutations the 2 founders bring with them. Each recessive lethal mutation present in the founders will represent one bad allele out of a total of 4 (since each founder has 2 copies). If we assume\* this allele is inherited such that its frequency doesn't change, then the population will have a 25% frequency of bad alleles for the spot in the genome. This means that a given child in the population will have a 6.25% (25% \* 25%) probability of receiving two bad copies of the allele and dying. So, for each recessive lethal mutation present in the 2 founders, ~6.25 percent of the future offspring of the population are going to die. This isn't entirely accurate because the recessive lethal mutations won't be passed on by those individuals who receive two copies and die, so the frequency of those alleles will gradually decrease as they are selected against.
So, how many recessive lethal mutations are our founders likely to carry? This recent paper <http://www.genetics.org/content/199/4/1243.full> claims only 1 to 2 per person. Even in the worst case of both founders bringing in two recessive lethal mutations for a total of 4, each offspring has a 93.75% (100-6.25) chance of avoiding two copies of each bad allele, meaning ~77% (93.75^4) of offspring will survive. As long as each couple produces 4 or more children on average the population will grow despite the high mortality rate. With each successive generation the frequencies of the recessive lethal alleles will decrease due to natural selection.
I haven't really addressed the question of how mating should be done. There are a couple surprising attributes of this population that make mate choice interesting. First, in a normal family tree mating with a more distant relative would be vastly preferable to mating with a close one, but in this scenario the there is no out-breeding, so distant relatives are actually just as likely to be carrying the same bad alleles as close ones. It's also unclear to me whether you would even want to try to reduce the number of problematic matings. Every time two heterozygote carriers for a lethal allele reproduce 1/4 of their children will die, but 1/3 of the surviving children won't carry the lethal mutation. Every mating that results in dead children actually reduces the frequency of the bad allele that caused it. So the population has a choice. By reducing matings between carriers of bad alleles they will decrease the number of dead children early on, but increase the number of total children that will die as the population expands. If your population has a scientific mindset they could record the manner in which the diseased children died and attempt to create a pedigree of the family's different genetic disorders to inform their mating choices, but it comes at a high cost.
One caveat of this analysis is that we are only considering recessive lethal mutations. There could be other detrimental recessive alleles that don't quite result in death, but still severely impair anyone with two bad copies. As long as they don't influence fertility they don't really impact our populations growth though, just how many issues our population is going to have.
Of course, we also aren't considering natural disasters, disease, starvation and other non-genetic factors here. If Adam gets pneumonia from wearing only a fig leaf around or Eve gets bitten by a venomous snake none of the genetics matter at all.
* Note: this is not a safe assumption. With 4 kids there's a 1/16 chance that the mutation will never be passed to any children, a 1/4 chance it will be passed to just one of them, a 3/8 chance it will be inherited by 2 of them, a 1/4 chance it will be received by 3 of them, and a 1/16 chance that the lethal allele will be present in all 4 of them. The outcome of this genetic lottery is extremely important and to properly perform our calculations we should consider each possibility but I fear that would make this answer even longer than it is and wouldn't meaningfully change the outcome.
[Answer]
The good news is that with no diseases around one consequence from your low genetic diversity is reduced. The bad news is that it's unlikely humanity will survive, however it is possible.
First we need to look at generation zero (g0). Astronauts tend to be older (average age 34), and also to have spent a lot of time in space being irradiated. Lets say we get a little bit lucky and both astronauts are still fertile and are at the younger end of the spectrum with the female being aged 30.
They have around 20 years of fertility remaining, although if they get unlucky it could be as few as none or 10 years.
If they produce one child per year and we assume an average of 1 survives each birth (which is not a forgone conclusion as modern medicine is going to be hard to access) then g0 was 2 people but g1 will be 10 to 20 people.
Now there are two choices, you can either pair off those 10 to 20 people with each other or for maximum use of the original genetic variation variation the g0 male can impregnate all the g1 females. (Using artificial insemination would make this less "icky" but you're going to have some form of incest whatever you do). I'm not sure which of these approaches is going to be the most beneficial genetically speaking, I think g1<->g1 is going to have the highest individual success rate but
g0<->g1 will introduce the largest overall variation into the population.
You should also consider rotating the pairs, in particular if a pair did produce a child that showed the consequences of inbreeding that pair should not mate again.
Whichever way you handle g1 you will want to create a tree mapping who is related to who and in each generation pair up the least related individuals. Any individuals born that show harmful effects of the inbreeding would not be allowed to breed themselves and both parents should be marked on the breeding chart as carrying that recessive. The parents should then be paired up with people who so far have not shown signs of carrying that recessive.
Over time genetic diversity will return and more conventional relationships can form but it will be many generations before it does.
[Answer]
As @mikenichols points out, a big problem is going to be the passing on of harmful genetic mutations through the forced incest.
If they are so unlucky that they both carry the same defective gene, this could be devastating. 25% of their children would display the defect. Combined with other genetic defects, this could be brutal. But if they're reasonably lucky and they don't, their grandchildren will still have a high infant mortality rate -- see Mike Nichols post and my comments on it -- but enough grandchildren should survive to carry on the human race. And the deaths will slowly reduce the incidence of the defective gene.
Presumably they will have less genetic diversity than the human race as a whole does now. While they'll be carrying many recessive genes, they're not going to have the full set of all the genes that are presently out there. (Barring some extraordinary coincidence, the odds against which would have to be astounding.) The best chance would be it the two people are genetically as far apart as possible, like if one of them is a white person from Norway and the other is a black person from Nigeria or some such. Still, plenty of isolated communities manage to survive and thrive. There have been tribes on remote islands or deep in the jungle who had no contact with the outside world for centuries, and yet seemed reasonably healthy. There is no reason to believe that this of itself would be an insurmountable problem. It may be that they just wouldn't have the genes to survive in some climates, or to live off of certain foods, etc, but that wouldn't be fatal.
Again referring to my comments on Nichols post, suppose it's true that the average person carries 60 mutations. Most of these are probably trivial: a funny shaped ear, a mole, that sort of thing. Some will be serious. It is likely that some will be serious enough to be debilitating or fatal in the right (or wrong) circumstances. Some that are not fatal themselves will prove to be fatal in combination with others.
Once lost, there's no way to get genetic diversity back. Well, mutations will create genetic diversity, but not the kind you want. Mutations are random damage, and random damage does not make things better. Try turning your Honda into a Rolls by throwing it over a cliff a few times and see how that helps. No one has ever observed an unquestionably beneficial mutation. Even if you buy that crazy evolution theory, to fit the observed facts you have to concede that beneficial mutations are extremely rare, so it would take hundreds of thousands of years to accumulate even a handful.
Another big problem that comes to mind: How do you maintain any sort of civilization or economy with such a small population? Suppose each woman has 10 children who survive to adulthood. That seems very optimistic, but even then: second generation = 10, third generation = 50, fourth generation = 250. Sustaining our present technology requires many thousands of specialists. You rely on the work and knowledge of others every day. Suppose they decide that they want to make some electrical wiring. They'd have to know where to go to find copper ore and how to recognize it. Then they have to know how to smelt it into usable metal and string it into wires. Will they make the insulation out of rubber? What does a rubber tree look like, and what is the process for extracting the rubber and turning it into a usable form? Etc. Even assuming that libraries survive and they can look stuff up, there are limits to how much one person can learn. They might be able to continue to use many existing artifacts, but building new ones or even repairing the ones they have would be very difficult. And many would rust or decay over time, so that within a few generations they're probably wouldn't be much of the old technology still usable. They'd have to start over in many ways. They'd have the advantage that if they're smart enough to keep the old books, than they wouldn't have to re-discover or re-invent things. This would be like the fall of Rome and knowledge preserved by monks times a million.
RE religious implications: The immediate descendants of Adam and Eve had to reproduce by incest, as did the immediate descendants of Noah. It wouldn't take any great theological leap to say, This is an extreme situation, God will surely allow us to break a general law as the alternative is the extinction of the human race, there is no harm to anyone other than ourselves, and there is more harm by not doing it than by doing it. I might note that personally, I'd see this as very different from a situation where the only way to survive is by harming others. I suppose there could be Christians or Jews or Muslims or whatever religion you suppose these people are who would dogmatically say that all commands from God must be understood as no exceptions under any circumstances, and therefore we have no choice but to allow the human race to end.
*Addendum: Rate of defects*
Confer Mike Nichols post.
Consider just one gene. Let's call the "good" gene "A" and the bad, mutated gene "a". Then let's assume that one parent is AA and the other is Aa.
So:
Generation 0: 1 AA + 1 Aa
Generation 1: 50% AA + 50% Aa
Generation 2: 25% will be children of AA+AA, 50% of AA+Aa, and 25% of Aa+Aa
Of the AA+AA, 100% are AA
Of the AA+Aa, 50% are AA and 50% Aa
Of the Aa+Aa, 25% are AA, 50% Aa, and 25% aa
Summing this up gives:
AA=25% x 100% + 50% x 50% + 25% x 25% = 25% + 25% + 6.25% = 56.25%
Aa=25% x 0% + 50% x 50% + 25% x 50% = 0 + 25% + 12.5% = 37.5%
aa=25% x 0% + 50% x 0% + 25% x 25% = 0 + 0 + 6.25%
So the grandchildren will have 6.25% incidence of a pair of bad genes, and thus show the recessive characteristic.
Assuming that each parent has 2 such bad genes, with no overlap of the 2, then there are 4 total bad genes, each of which will show up in 6.25% of the grandchildren. The probability of a child not having any one of these is 100 - 6.25 = 93.75. The probability of having none of the four is thus 93.75 ^ 4 = 77.25%. So -- assuming we are talking about fatal mutations here -- about 23% of the grandchildren will have at least one of the 4 fatal mutations, and die.
[Answer]
It's unlikely that they would be able to repopulate, since they're starting with such a limited amount of genetic diversity.
If they wanted to try, though, the wisest thing would be for them to pair off the children and have each set produce one or more kids, then mate the cousins and go from there. The initial couple would need to try to produce as many children of their own as possible.
[Answer]
Just as an alternate possibility: using your specific scenario, if they return to earth and there is still food available in supermarkets (so it's not something like a century later) - why not look for sperm samples in sperm banks?
I'm obviously not an expert when it comes to actually using such samples, but as astronauts they would probably have enough scientific knowledge to read informations about the procedures to do so. They have enough time to learn about it. If they still manage to conserve those samples for future generations, genetic diversity wouldn't be an issue.
] |
[Question]
[
In many sci-fi scenarii, most often when mechs are involved, it is not uncommon to see such a technology, usually called [heated blade](http://tvtropes.org/pmwiki/pmwiki.php/Main/HotBlade). Supposedly, it would make the blade even more efficient at cutting through anything; usually designed to cut through or pierce metal plating, melting it in the process.
Now the thing is, I love this kind of idea (if only for its sheer awesomeness, just like vibrating blades), but there is no way for it to work the same in real life; the temperature would need to be absurdly high to melt any metal that fast. Besides, the blade needs to have a higher fusion point, and with a temperature that high, I doubt there is anything that would work.
But I started wondering: given we are sufficiently technology advanced (assume at least common space travel, maybe even FTL-level if needed), how close can we get to it? As of today, the closest we have that I can think of are what is essentially a blade-shaped soldering iron, but that's because we have no need for heated weapons.
What if we can put it Up To The Next Level?
Restrictions and notes:
* The blade has to be solid; otherwise I could easily imagine lightsabers or futuristic blowtorches to be the ideal solution.
* It has to significantly increase the blade's cutting power. Glowing knives are cool but I want something that can do more than slice and toast bread at the same time.
* Any alloy or technology is allowed, as long as it's scientifically explainable. Does your sword uses the power of a nuclear plant in order to work? Alright no problem, as long as you can explain how to miniaturize all that in the blade (although I accept external solutions like powered suits).
* Of course we can handwave that, if such a material that can withstand such a temperature while maintaining a decent hardness is found, it is not often used for armor plating; maybe because of the cost.
* Size does not matter; if the blade has to be 10 feet long to accommodate for the needed technology, and as such can only be used by a mech, that's fine. All the better if you can make it human-sized, however.
Of course, I'm interested in the How, not in the Why. Never in the Why.
[Answer]
[With Lasers](http://tvtropes.org/pmwiki/pmwiki.php/Main/EverythingsCoolerWithLasers).
The blade is acually a metal sheath housing a series of prisms and optic fibers designed to guide the laser beam to exit in the direcion of the blade's cutting edge, and in the hilt is a powerful laser generator.
Sensors in the blade would detect the iminence of a slash, and trigger a series of actuators that would direct the laser beam along the blade edge, to cut the enemy's armor plating.
Once the laser created a gap, the blade would serve as a wedge to widen the breach.
Some glare from the laser's diffraction would make the blade glow, giving the likeness of being "hot"
[Answer]
I'd like to expand on @DoubleDouble's answer a bit, as cutting torches was my first thought reading the question as well.
Industrial cutting of steel is can be done using a couple of different techniques, for a sword type weapon your best bets are likely something along the lines of a an oxy-fuel torch or a plasma cutting torch.
In oxy-fuel (fuel like propane or acetylene) cutting you heat up a metal with torch, and once it's hot enough you hold a lever that adds additional high pressure air to "cut" the metal. Cut is a bit of a misnomer here since the excess oxygen jet is actually oxidizing the metal and air pressure is blowing away oxide (rust for steel), so it's slightly closer to high-temperature-rapid-directed-rusting =P. Drawbacks to this method will be fuel and usually a concentrated source of oxygen, generally this means high pressure gas tanks which can be pretty heavy not ideal for a person to lug around but probably acceptable on a mech. However the issue you'll see here is the "preheat" time before the cutting can start.
Plasma cutting is the arc welding equivalent to the oxy-fuel approach, a gas mixture is directed at the metal and an electrical arc is established across this gas flow which creates a plasma. The plasma heats up the metal and again the excess gas blow away molten metal. This process is faster and only requires one gas tank but also a good source of electrical energy for the arc.
Ideally you could have each blow of the sword "smartly" create several plasma cutting arcs along the edge do "burst" plasma cuts perhaps charged by high density capacitors and gas release valves.
One other quick thought though, both of these would require eye protection. Oxy-fuel would require welding lens shades of #2-3 and arc plasma cutting is normally in the range of ~#8 but for higher energy (capacitor bursts or other "high energy" hand waving) the lens may need to be #11 or #12. These are very dark shades and so the armor or mech may need to have a built in auto-darkening welding helmet type lens.
[Answer]
This is an induction heater. The amount of heat you can get out of it is, essentially, only dependent on how much power you have available, and being able to prevent the heated object from destroying the induction coil.
And here is a 2 minute attempt at building the sword.
Problems abound. Ceramics are hard and brittle, but this is a common problem with all swords. The weapon will remain somewhat usable as long as the jacket on either side mostly holds together. A steel induction core would allow a temperature just below it's own melting point - depending on alloy, this is likely around 2500 degrees Fahrenheit, or about 1370 degrees Celsius.
This particular design could never be held by an unshielded person, so we're probably talking about mechs or powered armor. Either way, hitting one with this would take an appendage with it, but not why you might think - we're not talking about "hot knife through butter" so much as "I annealed the thing I just hit and made it a little softer so I could destroy the inner workings." However, if you could subdue a victim and hold this thing to it's cockpit for a while, you'll have subdued the pilot; and certainly pressing it to something with force *will* eventually make it through. But I wouldn't expect something like this to work after more than, say, 10 swings against an armored target - 1 if your powered armor is particularly strong.
[Answer]
Apply nuclear waste vitrification technology to "hot" nuclear material and voila! Something which handles like a ceramic knife but is self-heating. This is bonkers, but in the same league as the [polonium laser rifle concept](http://www.defensereview.com/352003/TIS1.pdf) circulated by an actual defence contractor.
Advantages: inflicts radiation burns *through* steel plate, you just have to wave it around near the victim. Surface can be hot enough to burn skin.
Disadvantages: it's impossible to turn off, has a fairly short half-life, and is lethal to unshielded wielders. It's made of ceramic or glass and is therefore fragile.
[Answer]
A possibly modern approach that immediately comes to my mind, is that you have your blade, and you have many "cutting torch" flames built into the sword, so that they come out on either side of the cutting portion of the blade, angled so the flames create an "edge" in front of the blade. These probably have to be built in a way which, when the blade cuts, doesn't get them in physical contact with anything. (*Wish I could draw a picture, but I can't at the moment*)
Hopefully, since our blade itself shouldn't be getting heated "too" much, it will retain most of its strength.
I could see this working well for swords designed for cutting, if the sword was allowed to "hit" and stay there a moment to heat the enemy, and then use the slicing motion. As opposed to swords more designed for "crushing" where the majority of their damage comes from how hard and fast you swing it.
The obvious drawback is fuel, and whether all the space taken up by this sword and the fuel would be better used with more guns. ;)
---
Additional thoughts:
Using this sword, I would be afraid of coming across enemies which use normal swords, or just large spiked/blunt weapons, that are designed to just be heavy and solid. Blocking a direct blow from these weapons would probably break my sword...
In the way the sword in used, where prolonged contact is more beneficial, something like a chainsaw blade might make more sense in the overall design of how the weapon works.
[Answer]
The cutting effect of a blade is entirely down to force per unit area. A broadsword doesn't need to be particularly sharp if you've got a lot of weight (e.g. 6 ft of steel) behind it.
Within that context - being hot is going to be of negligible use. You won't 'cut' with a soldering iron or blowtorch, ever.
But what you might find as a reason for the hot-blade is cauterization - it'll stop bleeding if it's really hot, which'll mean someone isn't going to bleed out as quickly... but they might also never heal the wound afterwards.
The approach I could see working is similar to a thermal lance - which is essentially a pressurised oxygen flow, allowing metal (like magnesium) burn extremely hot. This won't cut particularly fast (although it will cut through basically anything).
But it's benefit in sword might be to heat up the armour your opponent is wearing, making it more malleable.
About the best I can give for the 'burning sword' approach is a self-sharping blade. E.g. heat the edge of the blade to lots, and then use a magnetic field to reshape it and re-align the atoms in it to make is really sharp. Impacts to a magnetic material will cause field reshuffling, and a sword that you've just hit something solid with is going to be nicked and dented in short order.
On a related point though - you've also got a water knife - using high pressure water as a cutting surface. I could envisage a 'water knife' type sword, but again it suffers from the same problem as the heat-blade, in that it's no longer an 'impact weapon' but rather a rather elaborate can-opener.
<http://www.flowwaterjet.com/en/waterjet-cutting/accessories/waterknife.aspx>
[Answer]
My approach is to use nanotechnology. The edge is covered with nano-disassemblers that take apart the material they are presented with. It doesn't have to reduce it to atoms, but separate enough to make dust partcles separate from the bulk.
The blade can have a selection of nanomachnes along the edge, and can deploy whatever is needed for metals, organics, minerals, etc.
For organic material, particular uv laser frequency can destroy bonds without heating neighboring tissue; this is used for Lasik and laser scalpels. Putting nanolasers on a mechanical scalpel (rather the weilding a fiber with bulky machines) is a natural continuation to make a medical tool. That can be beefed up to make a weapon.
[Answer]
You could have a light-saber-like weapon.
The main problem with this type of weapon in the real world is the containment of the "blade." If you weren't stuck on having a free-standing column of plasma (i.e. your sword would have a point) a light saber is theoretically possible if you could generate the energies it would require to create such a super-hot plasma. The "blade" portion wouldn't actually be touching anything due to magnetic containment, so it could actually be a feasible weapon.
[Answer]
Y'all are pikers. The handle of the sword is a power source. The core of the blade contains antimatter in a containment field. The antimatter is fed to the edge of the blade by use of mumble-mumble nanotechnological faster-mumble magnetic monopoles hand-waving superconductor more-mumbling sapphire/fullerene construction. The result is that the edge of the blade emits a narrow band of antimatter at low density, with the flow rate tailored locally to the proximity and velocity of approaching matter. The result is a powerful local energy release which vaporizes the target in a line which coincides with the edge of the sword, allowing it to cut through any material with ease. By the time the sword is in a position to make contact with the target, a channel the width of the sword has been cut into the target.
Eye protection is recommended.
[Answer]
was thinking about this and you could have a circular blade that folds in on itself (like those lightsaber toys) except have it fully enclosed (reason shall be explained) - at the very bottom of the blade have an inlet for a propane mixture, with a switch to activate a flame to light the mixture when needed (note: mixture would have to be replaced after every so often, but you could carry 'mags' and have the blade open on side, for a new canister to go in, would have to be pretty careful though) - that's the general idea. so I was thinking have a fully enclosed blade made of tungsten (melting point is VERY high, almost 3500ºC) about 30-40" long the blade would have to be put together, so it couldn't be a 'whip it out' type blade like in Star Wars, but you could put it together in advance, and just not activate until needed. According to my guesstimations, you could make a 30-40" blade in a hilt that could actually be wielded (maybe, I think)
[Answer]
Few alternatives to "laser-edged" blade.
Plasma cutter: a knife shaped device with edge that shoots hot accelerated plasma. We already use plasma cutters to cut metal plates.
Induction cutter: instead of using induction to heat the blade itself, the blade has a induction coil inside capable of causing inductive current in a surface that it's about to cut. This means instead of the blade, the surface of armor heats up, reducing heat stress and damage on the blade.
[Answer]
A plasma sword would be nice. I'm using those and vibro blades for a sci-fi book I'm writing. The plasma sword works by using the fusion core of a suit of powered armor as a source for the blade. Using a carbon nanotube tube to funnel the plasma from the core to the hilt and super conductive magnets in the hilt to stabilize the plasma and there you go.
[Answer]
Here is a little twist you might play with. The common, most effective armor going around is something like a composite, carbon fiber *yada yada* armor that is effective against most melee weapons, a host of projectile weapons, and so on. Every-one has it and it has become something that creates stalemates in ground battles. It's effective against most energy weapons. Anything strong enough to get through is impractical in small scale or precise battles..
How to get through it? It has a problem with high heat and steady pressures. Not something that is super easy with the current crop of weapons. Energy weapons that might get the heat won't produce the pressure and melee weapons and projectile weapons get the pressure but not the heat. Even things like current anti-tank rounds that inject molten copper into a tank are defeated by the ablative properties of the armor. You need something that will apply consistent heat and pressure over a relatively long period of time.
You can use a heated blade made of Tungsten/unobtanium alloy that will enable your guys to hit the armor with both heat and pressure in close engagements. Use induction powered by the proton pack on your back to heat the blade.
Maybe use it as some sort of assassination weapon. Cover your traces after the engagement. Once the enemy gets the idea that the armor can be beat in this way, they will begin looking for ways to either fix the weakness in the armor or try to make their own hot blades. Once the secret is out, the arms race just jumps to another level of stalemate.
sounds like fun. I know you asked for the what, not the Why, but the why often provides the keys to the what :)
] |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.