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ELI5:Why do Webpages "Bounce" back up to the top when loading the last few images when I have already scrolled down? | I will connect to a webpage that has loaded text but is still trying to load some pages or video. I have scrolled down to read something, and when the images or video finally loads, I am shot right back up to the top of the page. What is happening here? | In JavaScript you can set the "focus" to be on any specific item on the page. It's likely that the focus is set to something at the top of the page. Javascript can be told to run after the page finishes loading, which is why it will wait until after images load. May be more noticeable on mobile since slower download speeds and smaller screen space. | 71 | 287 |
[MARVEL] Could Mr. Fantastic walk on water by stretching his feet into pancakes, and if so how much surface area would he need to stretch them to? | There are two approaches he could take, spread his weight so that the surface tension supports him (pancake shaped feet), or displace more water than his total mass (bowl shaped feet). The second option would probably be more stable, essentially he'd turn his feet into little boats | 31 | 46 |
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ELI5: Are Formula 1 drivers the most skilled drivers in the world, or could some random people be unknowingly better drivers? | I mean I'm sure you need to know your racing to be a F1 driver, but are they the best drivers in the world, or could some people in the world unknowingly be better drivers than F1 champions?
I've been thinking, watching shows like Britain's Got Talent, new talents are discovered from people who don't look the part.
Could this be the case for race car drivers as well? Could someone have a hidden talent at driving F1 cars? How much of it is down to their connections and opportunities? | To be a Formula 1 driver, you need to have a detailed knowledge of how to drive a racing car. You need to be able to understand the engineering aspects of pretty much each area of the car, so you can work with the engineers to make it perform the way it needs to perform. You need to be physically fit, and have excellent reflexes.
Is it possible that there is someone out there, who, if they started racing karts at the age of 8, might be (or have been) better than the greatest Formula 1 driver ever? But instead, that person never set a foot inside a kart, and now works as an accountant? Yes, it's possible.
Is it possible that there's an accountant somewhere, who, if he was given a chance to drive a Formula 1 car tomorrow, and even if he was given 6 months to practice, would be better than the greatest Formula 1 drivers? No. He simply wouldn't have the experience, the knowledge, the fitness, the reflexes and so on, which the best drivers have been working on for literally their whole lives.
For an interesting insight into this, see if you can track down the Top Gear episode where Richard Hammond has a go in a Formula 1 car. Hammond is not a racing driver - but he has spent lots of time driving fast cars around racing tracks. Watching him struggle with the F1 car shows just how far Formula 1 is from the experiences of even people who are used to fast cars. | 16 | 16 |
If the materials making up the earth existed before the earth materialized, how can we tell the age of the earth? | If all the elements that make up everything on earth existed since the time they exploded out of a star, how can we tell a difference in age in any inorganic material? Shouldn't the ages only tell us the difference in time it takes for a star to form gold vs iron? | One method of radiometric dating involves comparing the ratio of uranium to lead within a sample of zircon (a common mineral in many rocks). Specific isotopes of uranium will decay to specific isotopes of lead with a known half life, independent of external conditions. Zircon eagerly incorporates uranium into its crystal lattice when forming, but excludes lead, therefore all lead within a sample must have started life as uranium. This is enough to determine how old a rock is. Since the earth was molten when formed, and any subsequent impacts by zircon crystals formed elsewhere would probably have melted the crystals, it is safe to assume the crystal formed on earth, after the earth began to cool, so the earth is at least as old as your rock.
Source: Sam Kean's The Disappearing Spoon (good science history book, highly recommended)
Edit: As FerretAres points out, this only gives a minimum age for the earth. The earth is most likely older than the oldest rocks, but this method provides an irrefutable floor for the earth's age | 105 | 276 |
ELI5: What is a slide rule, and why was it’s invention such a big deal? | Multiplying numbers is harder than adding them. You need to do a bunch of smaller multiplications then add them up, and there's plenty of scope for error.
Maths has a trick (invented by a Scot called John Napier) that lets you turn multiplication into addition. There's this thing called the logarithm, and if you take the log of two numbers and add them together, it gives you the same answer as multiplying the two numbers and then taking the log of that. In other words log(A)+log(B)=log(A×B). This means you could convert the numbers to logs, add them together (easy) and then convert the answer back.
But, logs are tricky. We can't easily do them in our heads. So we had to use charts known as log tables. You'd look up log(A) and log(B), add them together, then find the answer in the table to convert back. If this seems like a lot of effort with a lot of scope for error, that's because it is!
Slide rules simplify this process. Instead of having the numbers spaces out linearly so the distance from 1 to 2 is the same as the distance from 2 to 3, slide rules use a logarithmic scale. This means the distance from 1 to 10 is the same as the distance from 10 to 100. Effectively, the distance along the ruler becomes the log of the number. And slide rules have two of these scales on them which can slide past each other.
So, when you want to multiply A and B, all you do is slide the ruler so the 1 on one ruler is beside the A on the second. That means every number y on the first is now lined up with y×A on the second, because the distances are added together (and the distances are the logs of the numbers). Then you just look along to find B on the first ruler, and the number across from it on the second ruler is just A×B.
This takes complicated, intricate multiplications and turns them into sliding a thing and reading a number!
Edit: thanks, kind stranger :)
Edit2: and all you other strangers too. Who'd have thunk so many folk cared about the length of tools used for multiplying. Oh, wait... | 5,632 | 6,117 |
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ELI5: If CBS really does have new info/suspect in the JonBenet Ramsey case, why are they not required to turn it over to law enforcement? | Journalists are allowed some privilege when it comes to information and disclosing it or testifying about it, and by many avenues. Of course there is the first amendment right to a free press, but in addition, there is statutory protections, common law protections, and protections under many state constitutions. Mind you, these protections only apply to *information*. Any physical evidence would have to be turned over.
And CBS doesn't have shit. It's a marketing ploy. It's the 20th anniversary of her death and a number of stations/networks are claiming to have new information. None of it is really new. They're taking interviews with people positing their "new" hypotheses, nothing more. | 38 | 52 |
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CMV: Horoscopes, tarot cards, numerology, and those magic rocks are similar and all complete b.s. | People have been increasingly into those magic rocks that are some type of magic or hold some health and spiritual benefits. These are fake and akin to snake oil. These can be lumped into the same category as numerology, astrology, and clairvoyance. I think these can be dangerous for someone if they decide to live their lives based on any of this fairy tale bullshit. I'm hesitant to put these "essential oils" that people are huffing and defusing into the same category because I know some of these have been used pre-medicine to actually help people. I don't know if i need some sort of "proof" or just an explanation as to why the hell people have fallen for this stuff. Thanks for sharing your opinion and trying to enlighten me on this garbage.
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> *This is a footnote from the CMV moderators. We'd like to remind you of a couple of things. Firstly, please* ***[read through our rules](http://www.reddit.com/r/changemyview/wiki/rules)***. *If you see a comment that has broken one, it is more effective to report it than downvote it. Speaking of which,* ***[downvotes don't change views](http://www.reddit.com/r/changemyview/wiki/guidelines#wiki_upvoting.2Fdownvoting)****! Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | Tarot can offer a benefit even if you don't believe in magic powers; they're basically the equivalent of Rohrshach blots, where you pick out the symbolism that strikes you as meaningful and interpret accordingly. | 17 | 27 |
What important theories aren't taught to beginners that would've helped you when you started coding? | That PL theory and category theory are worth learning. A lot of times you learn these data structures across multiple languages, and PL theory and category theory unifies the constructs and allows you to talk about them at a higher level. It really defines standard interfaces, and a lot of documentation is starting to speak in the PL/CT language because it's more concise than reinventing the wheel explaining a concept in a low level, when you can explain the high level abstractions.
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Also, a lot of problems end up being a language problem. You'll find you're structurally doing the same thing over and over again, so translating your code into a standard interface is a step to unification, which makes it easier to communicate concepts and ideas between developers in your project and even new developers.
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A lot of people have this idea that "you don't need CS theory knowledge" and that everything is about fast code. It's wrong. Companies lose money because they don't develop code fast enough, and learning these concepts makes you deliver code faster, and maintain them easier. An overly optimized chunk of code for speed, that isn't in this standard language usually ends up being a liability, and I've learned many times people that don't write language in this way end up being wrong in the long run. | 26 | 41 |
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ELI5: How is gravity calculated for distant planets and moons? | How do we know the gravity for saturn is 107% of earths gravity, or how did we calculate the escape velocity for moon for the Apollo 11 mission. | Gravity is the same everywhere, there's the old Newton formula to calculate the gravitational force that depends on the masses of the two objects and the distance (radius) between their centers. There is also a formula for calculating orbital velocity based on the mass of the planet. So if you know the orbital period of a moon, and the distance, you can calculate the gravity of the planet. | 17 | 37 |
How to deal with an otherwise competent programmer with a belligerently weird style? | I work on a 5-person programming team (plus one supervisor). It's not a standard programming language and it's a small enough community that I am not going to name it here for the sake of anonymity.
We have a code style guide that we settled on which is mostly industry standard best practices, with a few extra additions specific to our company. Most of the guidelines had little to no opposition among the team when proposed, but there was two specific areas where one of the team spent well over an hour arguing over the superiority of his preference compared to what is the industry standard, and in the end our supervisor intervened and basically told him that he'd been outvoted and we, as a company, were going to do things the way the rest of us preferred and that was much more standard to do them.
Again, I can't name specifics, but I assure you that this isn't a small thing; it's effectively the equivalent of the ["indent with semicolons"](https://i.redd.it/1jh2k8j4dzo71.jpg) code style, but in the specialized language that we use. Sure, you can make a few arguments as to why it helps (like, sure, it does mean that you can never forget a semicolon at the end of a line, and you can visually see the indents so you don't have to check if they are spaces or tabs) but in the end it's so visually jarring compared to normal code and takes such a weird amount of extra work to do that it's definitely not worth it. And he's been here long enough that he's writing code that is now starting to be integrated into the company code libraries, thus making the rest of us now have to see and often debug code written in his weird and annoying style.
The problem is that this guy, with the exception of his fixation on this one bizarre code style, is actually pretty good at what he does, and it would be really difficult to replace him because not only would we have to find someone who knows the somewhat obscure language at a high skill level, it would take weeks or months for them to reach his level of familiarity with company-specific systems. And hiring anyone right now is difficult enough what with the world being the way it is...
So I ask you all, is there anything in general that you can think of that could be done here? I've considered writing a script to parse his code and remove the weirdness, but he could just revert it back in source control plus my boss would call it a waste of time. Because he's writing otherwise good code, he won't get fired over this. The best I can think of is that on his next review he gets marked down for not being a team player, and gets a sub-par raise, and either quits or changes his mind, but I don't see that as a strong possibility. I have talked to our supervisor already, who talked to the guy, who basically said that he is still convinced his is the better way and he's not going to stop doing it despite being outnumbered 5 to 1.
Edit: General response to the ~50% of responses suggesting plugins/linters/whatever to automatically reformat his code or reject it before committing: With this language and the development environment we use, that isn't possible with the source control we use. If I want to "correct" any of his stuff, the only option is to get his last commit, alter it, then submit that as my commit, and it's only partially automatable. I'd end up spending roughly 25% of my time reformatting his stuff. | The correct thing is for your supervisor/manager to deal with it. If that doesn't happen though, there's an obvious technical solution: set up a repository hook to reject non-compliant code at commit time. | 26 | 21 |
[Star Wars] Why are there only two schools of the Force instead of many like we see with religions in our world? | There are many different ways of understanding and harnessing the Force.
Only the Jedi and Sith beliefs has spreading their belief on their agenda, though, letting them grow big, spreading all over the galaxy, as opposed to staying in a few systems. | 29 | 20 |
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Why are there so many acidic fruits, but few if any alkaline ones? | Fruits are "designed" by natural selection to lure animals to help spread their seeds in exchange for a nutritious snack. Therefore fruits must be apetising to the target animals. Most animals use acids as a part of their digestion and therefore alkaline substances, which react with acids can, at least make digestion less efficient, and at worst create toxic or dangerous by products when consumed. This is why acidic foods taste sour, which is a pleasant taste as long as it isn't too strong. But alkaline foods taste bitter, which leads to them initially being unpleasant (you can acquire a taste for bitter foods like coffee, if they end up being safe and bring other pleasant sensations like a caffeine buzz). Because of the predisposition of animals to avoid bitter foods on first tasting them, it is not to a plant's advantage to produce an alkaline fruit. It will scare off potential seed vectors. | 16 | 39 |
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After going through a modern embalming, how long does it take a body to decompose once buried? | I've always wondered what our bodies look like a week/month/year after being buried...
Any thoughts? | As a funeral director, this would depend on the condition of the body prior to embalming. Obesity, trauma, advanced decomp and other factors influence the efficacy of the formaldehyde. Also, the strength of the embalming fluid (mixed by the embalmer) will determine how long a body holds up. In summary, it depends. Worst case, one week, best case, months. Expert embalming and good body condition may preserve for years. *note; Decomp begins immediately after death. | 706 | 1,453 |
ELI5:How come after hundreds of millions of years and 5 Extinction Level Events throughout Earth's history, humans are the only species to become "intelligent"? | Why is it that humans are the only ones that have created a civilization in the entire history of the earth? Billions of years and 5 mass extinctions and Earth comes up with us *now*? Why not earlier? Why not another species? | You're asking this as though being intelligent is something special that all species should strive for. It isn't. Being able to survive is the best ability you can have from the evolutionary perspective.
Why is it that the mantis shrimp is the only species to evolve their awesome punch? Why are beavers the only species to be so good at building dams? Why are peregrine falcons the only species to evolve to swoop down and attack before anybody realizes what's happened? Because it fills their niche in the environment and lets them survive. So do we.
In much the same way that a slightly slower falcon would lose out to the faster ones if it tried to compete for the same food any other species that got intelligent and started building societies with tools, manual dexterity and all that would compete with us and either we'd win or they would. We had this fight already with other hominid species. We won. | 66 | 67 |
In a fully automated manufacturing and distribution
society, what happens? | Let's say we get to the point where factories and robots can do all the jobs of building structures , manufacturing, maintaining and distributing manufactured goods at a cost below that of human subsistence. Furthermore, many services can be handled via AI or AI networked robots. This is likely thought only with the existence of a mass market that can purchase the goods and services.
This the leaves the jobs of research, design, some small numbers for management and admin functions.
So likely a large majority of people is not needed.
And if something like a huge majority of people don't have work/income, who are the producers of goods and services selling to? Despite being able to provide for a huge mass market, this scenario means that there is no mass market.
Is there some sort of balance or equilibrium that is known to social science that can describe how this plays out? | A distribution system like that would mean that goods would be produced with little effort, meaning the amount the producers would be willing to part with for material goods would be very small. The economy does not exist to satisfy material wants, it exists to serve any human wants - the mastery of material production would simply mean people would shift their productive energies to non-material things. At one time a vast majority of the population was focused on providing other people with food and a vast majority of people's spending was on feeding themselves. When technology shifted to make food production less strenuous, people directed their new-found excess incomes elsewhere, and people were happy to try to find new goods and activities to compete for that income.
If producers can literally provide a year's supply of food at a press of a button (in this future example), and an automated system converts solar energy into food, all you need to do to get a years' supply of food is to persuade one of the producers of food to press a button for you. Who knows, we could have an economy based around lolcats and upvotes. The nature of employment will be different, but it will still be there (whether we want to call it employment or not) - it's simply the direction of human will and effort to satisfying other people, whether in a roundabout process like farming or in more direct ways like services. Only when there is - literally - no way for one person to satisfy another person's want will this be an issue, and in a world of such abundance nobody would bother protecting their material property anyway, it would be like air. Very few people put energy into keeping other people from breathing their air. | 11 | 19 |
Eli5: Why/how do still images like this one look like they're moving? | Optical illusions like: https://imgur.com/gallery/NOg2QCo
How do they trick the eyes/brain into thinking its moving? | Well, human brain tries to interpret the image it sees in a way that makes the most sense to it, though it may not always be correct. So simply said, it is just an error in the way brain interpretes the image eyes capture, as it tries to make sense of it. The shapes, colors and their positioning used in optical illusions are usually not found in the nature or environment around us on a regular basis (often mimicking 3D space on a 2D paper), so the brain doesn't really know what it is supposed to look like exactly, thus fooling it into seeing something that is not really there, but makes most sense to the brain at that moment. Optical illusions sometimes require a certain angle of viewpoint or you have to be able to see it entirely, so there are ways to "see through" optical illusions by either focusing on a certain point, or removing a part of the illusion by lowering your field of view with hands. | 60 | 64 |
[Doctor Who] Can a TARDIS take any form? | So, the Doctor's TARDIS has taken the form of a police telephone box to better blend in with modern society. But, what are the limits of a TARDIS' forms? How often can it change? Could a Time Lord appear in, say, the telephone box form, change its form to a smaller pocket-size version and carry it around and have it shift back when needed? | IIRC, *ideally*, it arrives somewhere, scans the environment to determine what would be least conspicuous, then transforms into whatever that is. What the Doctor's Tardis does is arrive, scan the environment, determine what would be least conspicuous, and then just turns into a police box anyway. | 70 | 33 |
Why is our current understanding of gravity unable to explain the rotational speed of galaxies without adding unseen mass (via dark matter) to the equation? | I have read that the the stars moving on the outside of galaxies would fly out of orbit at their speeds. Why is gravity not considered strong enough to keep them in orbit? | An orbit is a balance between an object's inertia carrying it outward and gravity pulling it in. If an object is moving fast enough, its inertia will carry it outwards fast enough that the cumulative effect of its parent body's gravity will never be enough to pull it back in. This speed is the escape velocity, and it can be calculated based on the total mass of the system and the initial altitude of the orbiting object. Based on the apparent mass of other galaxies, the outer stars should be moving at escape velocity, but somehow they're remaining in orbit. | 19 | 23 |
CMV: Andrew Yang's plan to give all Americans $1,000 per month would do little more than dramatically increase rent prices and other prices as well. | It seems like a universal and equal influx of cash like that without a change in supply will only lead to higher prices. Especially in areas like housing, etc. Most people it seems, who are renters, given an extra $1k/mo would want to move to a nicer apartment. Given a much higher demand for nicer apartments, landlords will be able to increase prices and maintain full occupancy. Similarly, cheaper housing could see an increase in price, because people would have the ability to pay and no other option. This extra money flooding the market does not come from an increase in supply or labor, so I don't see anything to keep market forces from doing their thing. I don't really see the upside.
I understand the arguments for UBI IFF automation and AI take away enough jobs to tank the economy. But right now, unemployment is extremely low, and implementing his plan would just effectively lead to inflation.
You can change my view by demonstrating that areas that have seen extensive UNIVERSAL basic income have not seen price increases. Also, I could be convinced by a logical, coherent argument showing that there's a flaw in my reasoning. | Another benefit of UBI would be to raise wages and perhaps get more people off of welfare to work even if that is counter-intuitive.
For people making near minimum wage the thousand bucks a month would be practically as much as they are making now. If they are content with things they could just stay home. That will force employers to raise wages. You will also see economic growth from the fact that people would have a safety net if they want to find a better job or a job more suited to their talents and passions. Right now any interruption in work could mean eviction. With a UBI you will have people seeking out jobs they are better suited for and that should increase economic growth.
Lastly, some people who rely on the current kinds of government assistance that exist have to prove they are poor enough to "deserve" it. That means if you get a job, even a minimum wage job, you could lose your healthcare/housing assistance/etc. So people will not take a job because the added wages don't offset what they lose. With UBI as your safety net you are always free to try and better your situation, apply for jobs, take on work just to see if it's a good fit, etc. That makes everyone more mobile and should contribute to economic growth. | 1,679 | 2,845 |
ELI5: Why are male Homo sapiens typically stronger than females when the opposite is true for most other spiecies? | Emphasis on most.
I was watching a documentary and they said that females are typically larger, stronger, and more aggressive then the males. Why isn't this true in humans? | A lot of those species, in which the female is larger, stronger and more aggressive than the male are species where the animals are solitary. For a female to be bigger and more aggressive than the male helps her when she needs to protect herself while pregnant / needs to protect her young afterwards.
Humans, however, are social animals so women aren't supposed to rely only on themselves while pregnant. They have the protection of the group. | 77 | 38 |
ELI5 How are large sums of money transferred between nations? | Say country A sends some billions of dollars to country B in aid or in exchange for some resource. How does the actual transfer take place? How does the wealth of country A decrease and the wealth of country B increase? | Nations have state banks, such as the federal reserve in the United States. The transactions happen over a wire system, like fedwire or swift. In straightforward transaction like you are supposing, it's just like any other international money transfer, only with larger amounts and between public banks controlled by the state. | 392 | 493 |
ELI5: why are people harder to pick up as "dead weight" as opposed to when they're letting you lift them? they don't really change weight | They don't change weight, but they do shift and support their weight to make it easier for you to grab and maintain balance.
That's also why a 45 pound block of wood is easy to lift but a 45 pound bag of water is a nightmare. You can't grab or balance the water and its center of gravity is constantly shifting as you fumble with it. | 129 | 53 |
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[EVE Online] Why can't I stuff cargo into the ore hold of my Retriever? | Well yes i know it's called an *ore* hold, but it's an entire frikkin' 23500m^3 compared to the 450m^3 of my cargo hold. Why can't I put these 10000 Soil into the ore hold? | Ore is ore. It's stone, rock, and minerals. Except in the rarest of cases, they don't need to be stored in special conditions. With most cargo, however, you need some sort of environmental and atmospheric control. In the case of the soil you mentioned, it needs to remain in an oxygenated environment to maintain its quality. | 27 | 19 |
ELI5: How legit is Judge Judy? (TV personality) | From a legal point of view, Judge Judy operates as an independent mediator between two parties. The parties are asked to sign an agreement before going on the show, agreeing that whatever Judge Judy decides will be the final decision. This has all the same weight in law as any written contract - in other words, it is legit.
The show sometimes accepts requests from people to appear on it. But they also search through court listings and approach people to ask if they want to appear on it. In return for appearing on the show, the parties have their transport to the studios paid for, and are put up in a hotel for the duration of filming.
The other thing which encourages people to appear, but which makes the show less-than-legit, is that when Judge Judy orders one party to make a payment to the other party, it is actually the show which makes this payment, so no one will be financially out of pocket as a result of the show. | 79 | 71 |
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Is the South Korean economic miracle an example of successful corporatism? If so, why did South Korean corporatism succeed while Italian Corporatism didn't? | From the looks of it, it seems like blatant corporatism, Park-Chung Hee wants to industrialize his country, he establishes direct ties with businesses like Samsung, Hyundai and LG that soon morphs into Chaebols, he helps them in any way he can, he offers them low interest rates, offers subsidies, etc. If that's the case, why did Italian Corporatism under Mussolini fail? | If you look at the developmental economics literature they attribute a lot of the differences in success to institutions and other government policies. Italy had a rampant history of corruption and nepotism, Germany and Japan did not. Later Korea protected its domestic industries but internally had quite stiff competition with the most successful firms gaining support for their production with the end goal of exporting goods. Japan had a somewhat similar system (the chaebol is based on the zeibatsu). And Japan’s economic development was modeled on Germany where the state provided the needed capital to firms, as their internal capital markets weren’t as developed as Britain’s. | 30 | 32 |
ELI5: When a container is sealed we call it 'airtight', is this the same as watertight or do liquids and gasses escape at different rates? | The molecules involved can be different sizes. An airtight object is water tight (assuming it doesn't fail). A watertight object is not necessarily air tight. A gap too small to let water in could potentially let air out. Some gasses can be even smaller. Helium balloons will actually leak helium through the skin of the balloon, for instance, over time. | 12 | 24 |
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CMV: Religious tollerance is pointless, religions are not equal and have no place in modern society | Specifically regarding the "big 3" (Christians, Jews, Muslims) but most religions have similar issues.
Firstly I'll start by saying I would never persicute a person for their religious beleifs. But, claiming all religons are equal is simply incorrect in my view. Granted, all adherants to a religion do not hold the same beliefs, but this is based in the personal choice of the adherants to not follow their scripture. I.e. The bible states clearly that homsexuality is a sin. This is a belief incompatible with the modern world so by claiming yourself tobe Christian, I will assume you hold antiquard beleifs untill such time as you deny them. After that Ill just think you are an imbicile for not undestanding your scripture. Any person who openly identifies as a religious adherant must accept the consequences that they will be judged on the merits of their religion untill they prove they do not hold the regressive views of their religion.
Edit: Ill also add that this only applies to people living in a situation in which their freedom to express any religious sentiment is a given.
Edit 2: religious adherants are not all the same and the majority do not hold the beleifs of their texts to be law and the dialogue coming from religious entities is normally hijacked by extremists who do view the text as sacred. Still, no matter how moderate contemporary Nazis may become I see no reason to associate with them.
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> *Hello, users of CMV! This is a footnote from your moderators. We'd just like to remind you of a couple of things. Firstly, please remember to* ***[read through our rules](http://www.reddit.com/r/changemyview/wiki/rules)***. *If you see a comment that has broken one, it is more effective to report it than downvote it. Speaking of which,* ***[downvotes don't change views](http://www.reddit.com/r/changemyview/wiki/guidelines#wiki_upvoting.2Fdownvoting)****! If you are thinking about submitting a CMV yourself, please have a look through our* ***[popular topics wiki](http://www.reddit.com/r/changemyview/wiki/populartopics)*** *first. Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | It seems to me that a large part of your belief stems from the fact that you want to impose on religion a literalist reading of the scripture the religion claims to follow. (You say that to be Christian is to accept that homosexuality is a sin and that those who purport to be Christian and not believe homosexuality is a sin is to simply be ignorant of the scripture.) But for many religious people, accepting that their scripture is literally true is not a tenant of their faith. For example, the Catholic Church doesn't insist on a literal reading of the Bible.
There are certainly people in every religion with a scripture that insist that the scripture is the literal 100% truth, but it is far from the case that one must accept that to be a member of any given faith.
And once you see that religion doesn't entail a literal reading of that religion's scripture, it seems most of your objection disapears. Because the "regressive views" of the religion that you see religion entailing are not necessarily part of the religion (though, again, they are part of the religion for many people). | 151 | 183 |
ELI5: Why do some colors shift when looking at things on an LCD screen from different angles? | Looking at [this](http://www.clker.com/cliparts/a/1/C/x/k/E/pink-square-md.png) from above makes it seem bright blue, and below dark red. That's just one example of many. | Lcd screens have several layers. First is the light source, often just around the edge. Second comes a diffusion layer to make that light even across the screen. Finally you get the lcd colour layer, which blocks the light in order to make the colours. When viewed from different angles, that blocking is imperfect, resulting in different colours.
| 17 | 47 |
What is so special about the relationship between circular/spherical objects' dimensions | I just completed uni-level calc 1 last semester, and one relationship I noticed right away was between the circumference of a circle and it's area. I noticed that if you take the antiderivative of the circumference formula (2pi * r), you get the area formula of a circle (pi * r^2). I noticed the same relationship occurs with the surface area and volume of a sphere (4pi * r^2 and 4pi/3 * r^3). This leads me to believe this surely cannot just be a coincidence. But as far as I've noticed, this relationship only occurs with smooth, rounded objects. For example, there perimeter formula for a square and it's area formula do not seem to share this same relationship. Why is this? Why only for circles and spheres?
This also leads me to some other questions, such as what if we continued taking the antiderivative and derivative of these formulas, eg pi/3 * r^4 and 8pi * r? What would these formulas represent in relation to a sphere. And does this same dimensions relationship work with a hypersphere as well?
I apologize if all of this is common knowledge in higher levels of math and if the answer is obvious, but for me it feels almost like a revelation since I randomly came across it on my own. I imagine it has something to do with the fundamental theorem of calculus, but why does it only seem to work with circles and spheres and not other shapes and objects? | What do you get if you integrate a segment of a horizontal line? How can you relate that to the area of squares or rectangles?
If you know the standard form of the equation of a circle, how can you organise an integration that would allow you to determine the area? | 11 | 26 |
How can astronomers work out the size and mass of exoplanets when they're literally just a few pixels wide in a photograph? | In very simple terms, the size of an exoplanet can be approximated by measuring how much the star's brightness dips as the planet passes between the star and Earth. The reduction of brightness is going to be proportional to the occlusion caused by the planet.
The mass of a planet can be inferred from its radial velocity, which can be measured by the orbital wobble that it causes in the parent star. This can be calculated by measuring red /blue shifts in the star's emission wavelengths during the planet's orbit. | 18 | 22 |
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ELI5: Why is cold water from the sink clear, while very hot water from the sink is cloudy white? | Unlike solids and liquids, gas has an inverse relationship between solubility in water and temperature of the water. This means the warmer the water, the LESS gas it can absorb! The water is entering your hot water tank cold, then being heated under pressure, preventing any dissolved gasses from escaping (yeah, your hot water tank is kind of a pressurized bomb, but anyhoo). The water is kept under pressure until it finally emerges from your tap, where it encounters an aerator, designed to introduce even more gas into the water. So, predictably, the gas comes out of solution quickly, causing the bubble you see! | 322 | 222 |
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CMV: 'Degrowth' as a political, economic, and social movement is required to combat Climate Change and ecological degradation, and to minimize their impacts | I am confident few here have heard of Degrowth, therefore bear with me while I provide a fundamental grounding of Degrowth. Know that this grounding is merely the very surface layer of a complex, multi-disciplinary web of theories.
**The basis of my view**
Degrowth has been around for decades as a theory, but is reinforced today by the empirical scientific consensus that exists. The current scientific consensus surrounding Climate Change and ecological breakdown is extremely strong. Three months ago 15,000 scientists signed a "Warning of a Climate Emergency" paper stating that without immediate radical action to reduce greenhouse gas emissions we may well be on an irreversible pathway of catastrophic conditions. Regarding ecological breakdown, species loss is occuring at an unnatural rate, global surface temperature is rising, wildfire intensity and frequency is increasing, large natural disasters are becoming more frequent, and half of all coral reefs have died over the past half-century.
**The reason behind my view**
The theory of Degrowth is, at its core, a critique of the environmental costs of economic growth. It argues that the faster we (humanity) produce and consume goods, the more we interfere and cause damage to the environment. If we are to avoid destroying our life support systems, the theory claims a slowdown (degrowth) is required in the global economy. The conslusion is that we should therefore "extract, produce, and consume *less*" (Kallis, 2017), while also aiming to increase well-being across many parts of the world; this latter part highlights the social approach of degrowth that promotes greater social equality, redistribution of incomes, and the meeting of basic human needs for everyone worldwide.
**CMV**
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​
N.B.
**RE: Technological Optimism:** I believe it's a fallacy to count on future technologies to save us. Previous instances of this occuring does not gurantee for it to occur in the future, and I would argue that technological process (unless you're a believer that superintelligence will save us from everything, or something similar) will not reap the required benefits to avoid catastrophe; they will play a role, but only in conjunction with Degrowth do I believe we can avoid catastrophic consequences.
**RE: Political feasibility:** I am not discussing here the political feasibility of degrowth, merely whether there are other options that will lead to avoiding 2°C
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​
**Sources:**
World Scientists' Warning of a Climate Emergency - [https://academic.oup.com/bioscience/advance-article/doi/10.1093/biosci/biz088/5610806](https://academic.oup.com/bioscience/advance-article/doi/10.1093/biosci/biz088/5610806)
Kallis, G., 2018. Degrowth - a recommended book on Degrowth | Your premise is that degrowth is required. Then you dismiss as possible two material factors. Political aspects indicate that the degrowth strategy may be politically infeasible. You dismiss technological advancement as impossible though it's the recurrent history of our species.
I'd like to encourage you to re-consider economic growth and its benefits. You're saying economic growth requires technologies that don't yet exist. Ok, let's ignore technologies that don't exist and focus only on those that do exist.
Today, the world has the technology to replace its surface transportation fleets with electric drives. This could reduce CO2 emissions of the surface transportation fleet by 20-25%.
Today, the world has the technology to replace its fossil fuel electric power generation with nuclear fission generation, solar, wind, hydro, & geothermal power generation.
Today, technology exists to reflect solar radiation arriving at Earth back to space. | 15 | 29 |
ELI5: Why are vegetables more consistent than fruits? | Everybody's had that awesome clementine that's sweet and juicy, and the one that's dry and a little sour. Or the grapes that aren't as firm as they should be \(even sharing the same cluster as awesome grapes\). Or the flavorless pineapple. But broccoli is always just broccoli. Asparagus can be skinnier or fatter but it's still asparagus. It seems like it's more than just ripeness. Why does the quality of fruit seem so much more inconsistent than that of vegetables? | Vegetables can be bred faster since most of them are annual plants (they grow and produce seeds every year). In contrast, many fruits come from trees that often take ~5-10 years before fruiting. Therefore, it is easier to select and breed vegetables for desirable traits.
For supermarket vegetables, the main properties you would want are that they look good and that they store longer. Taste is usually an afterthought. Therefore, supermarket vegetables taste consistently "meh".
If you do have the chance to grow your own vegetables or eat fresh from the farm, you will find that vegetables can also have variations in taste. But in general they taste much better than supermarket vegetables.
| 16 | 30 |
Is empathy a prerequisite to being a therapist? | Do good therapists exist that have low empathy? | Speaking as a currently practicing mental health therapist, empathy is essential. If you cannot empathize with the position your clients find themselves in, your clients will notice. That will affect their ability to trust you, which in turn affects the working relationship.
That said, it is also essential to learn how to compartmentalize. Otherwise you're going to get burned out very quickly, and then you will also not be able to treat your clients effectively. | 103 | 57 |
ELI5:How come the price of Oil went from 100$ a barrel to 27$ and the Oil price in my country went from 1,5€ per liter to 1,15€ per liter. | It makes no sense in my eyes. I know taxes make up for the majority of the price but still its a change of 73%, while the price of oil changed for 35%. If all the prices of manufacturing stay the same it should go down more right?
Edit: A lot of people try to explain to me like the top rated guy has that if one resource goes down by half the whole product doesnt go down by half which i totally understand its really basic. I just cant find any constant correlation between crude oil over the years and the gas price changes. It just seems to go faster up than down and that the country is playing with taxes as they wish to make up for their bad economic policies. | Suppose you want to make a grilled cheese sandwich. You go to the store and buy cheese (crude oil), bread (refining), and butter (taxes). If each of these cost $1, your sandwich costs $3 to make. Now suppose cheese is on sale for half price. The cost of your sandwich went down to $2.50, not $1.50 because the other ingredients still cost the same.
Edit: forgot a word. | 5,424 | 4,774 |
ELI5: How does wifi work? | It's just like this weird force. | Wi-Fi is a wireless networking technology that uses radio waves to provide wireless network connections using the IEEE 802.11x standard protocol. The communication is two way between a computer's wireless adapter and a router and uses the Radio Frequency (RF). When RF current is supplied to an antenna, it creates an electromagnetic field that propagates through space.
The wireless adapter converts data from the computer into radio signals and transmits it using an antenna. The wireless router receives the signal and decodes it. The router then sends the information to the internet using an Ethernet connection. When the router receives information from the internet, it translates it into a radio signal and sends it to the computer's wireless adapter.
| 15 | 16 |
ELI5: how does a (formula 1) car wheel spin without much resistance? | Currently watching F1 and seeing those wheels spin super fast. I'm really curious how the wheels and axels, which hold all the weight of the car, don't wear that quickly. Same as in regular cars. | Each part in an F1 car is built to precise specifications in not just weight but also mileage. Parts are usually made of high strength, low weight materials like titanium and carbon fibre. And they get swapped out during pitstops and over the race weekend.
So they don't have to last for a long time, or even an entire race weekend. Unlike a family car where parts are built for endurance rather than performance.
P.S. Great start to the race, but looks like it's settled down to the usual fare now. | 37 | 23 |
In what way is time a dimension? Why is it called the fourth dimension? | You define something's location with coordinates. On a line, you need one number. This is one dimensional. On a sheet of paper, you need two numbers - two dimensional.
In a three dimensional world you need three numbers to define where something is. Now, what if we had things like photons that can be absorbed and emitted? Three numbers is great, but it can't tell us anything about when that photon was emitted. So we add another number, time. A fourth dimension.
It's like saying "I'll meet you at the train station at noon." The train station has three numbers to define where it is. But you have to add another number for the time that you'll be there. | 38 | 27 |
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Eli5: what is EBITDA and why is it so important to executives? | Ebitda is effectively a term used to demonstrate the earning ability of a company
It stands for Earnings Before Interest, Taxes, Depreciation, and Amortization. So what does that mean? Those 4 expenses listed are things that are going to happen regardless of the business function of the company, they have nothing to do with how the company is run (for example, everybody has to pay taxes, all physical assets will depreciate over time, etc). As such, if you want to make an apples to apples comparison across companies, you can strip those out and see how much the company is actually earning, regardless of the so called costs of doing business that have nothing to do with the actual running of the company
Alternatively, it’s just a fancy accounting term to make companies look better than their actual bottom line | 64 | 56 |
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What is the best book about the feud between Sartre and Camus? | The title says it all. I see "The boxer and the goalkeeper" pop up a lot, but read some negative comments about it and was wondering if other books better describe this moment in history. | There aren't particularly many books which focus on this at all, but if you'd like a nice and general idea of their relationship, *At The Existentialist Café* by **Sarah Bakewell** is an excellent read. It tells the story of existentialism and its development and delves into the lives of the existentialists themselves, including Sartre and Camus. It's a really fun read and gives you an idea of how the two were with each other. | 72 | 79 |
ELI5: Why do expensive hotels have private wifi for sale while crappy motels have free wifi? | You have to look at the business model and the potential customers that each is trying to attract.
Crappy motels are trying to compete on cheap price and convenience, looking for bargain-seeking tourists. So offering OMG FREE wi-fi is a big draw.
Expensive hotels primarily cater to business clientele and convention goers. Most of them either have an expense account (so they don't really care because they just pass on the cost to their employer or client), and/or NEED to get onto the Internet because of work. Also in general these people have are less price sensitive.
Also sometimes when a large business goes through a travel agency, the people in charge of booking just care about price of the hotel room. The expense reporting goes to another division. So they don't really care that the wifi costs more because it's not a line item for them, which means they'd rather book at a cheaper hotel with jacked up wifi prices, than a more expensive one with free wifi. (Note that these people still aren't competing with the budget motels because usually the company has a certain standard that a hotel has to meet, and budget motels fall short.) | 128 | 234 |
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U.S. Media has been largely criticized as inadequate, sensationalist, and celebrity focused. What kind of policy change can be made to change this and what evidence exists in support of this claim? | Is there any way to theoretically change the standard in U.S. Media? A large problem is that celebrity news and sensationalist headlines often get the viewers and make the money. Journalism as it is is struggling as the Internet grows -- not only because everyone gets their news for free now, but also because news organizations now recognize that the gossip and entertainment get the most clicks and therefore the most ad revenue. Journalism is also considered entertainment media so they don't even necessarily have to be accurate (according to *The Corporation*)
The Netherlands and Sweden have government subsidized news media which takes out the money incentive but puts a focus on quality. Could a similar policy or other policies work in the United States? Also, many of these things I've heard in class or online without any real statistics or tangible evidence. Does this evidence exist? These things interest me and are important to me but I'd hate to be talking out of my ass. | If you want to change the media, start with the consumers. The issues with the media are a symptom of a larger problem. Namely, that the American education system sucks. People who are better educated are more discerning news consumers. When that happens, the market for news and information will respond accordingly. | 17 | 29 |
ELI5: how come foam is always white even though shampoos are all different colors? | Things are white when they reflect a lot of light (things are black when they don’t reflect light). The surface of bubbles is shiny, it reflects light. When you make foam, you’re making lots and lots of little bubbles. Since lots of bubbles have more surface area than one single bubble, it means more light can get reflected so your foam looks white.
Same thing happens if you’ve ever seen people make pulled taffy. They start out with a dark mixture and it gets lighter in colour as they fold and pull it because they’re incorporating bubbles.
They keep their colour because there’s more dye in it.
Edit: taffy | 139 | 129 |
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ELI5: Why is dental health so strongly dependent on brushing our teeth and flossing when our ancestors hundreds of years ago did not do the same? Did they have some separate mode of dental upkeep or were they just constantly losing teeth/have just awful mouth conditions? | It depends on what time period you’re talking about. Hunter gatherers prior to the advent of agriculture tended to have very healthy teeth. This was the result of two primary factors: far less carbohydrates in their diet and a lot of grit i.e. sand, silt, etc. in the food. Their teeth tend to be heavily worn down, but otherwise healthy. In early agricultural societies dental health tends to be way worse as a result of lots more carbs/sugars in the diet, softer foods, and obviously no fluoride toothpaste.
Now all that said, if you were in any preindustrial society and you developed a dental problem, it could become extremely serious and without doubt people were aware of this. Abscesses can form and basically rot out chunks of your jaw or even kill you. Based on observations of living and recent preindustrial societies, both agriculturalists and hunter gatherers likely used things like thorns and chewing sticks to clean their teeth regularly.
Source: I’m an archaeologist | 100 | 64 |
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ELI5: How does brainwashing actually work? | People throw around the world ‘brainwashing’ a lot but I still don’t know what it means. Is it a ‘repeated truth’? Is it certain mind tricks? Is it some kind of chemical thing?
Disclaimer: not looking to brainwash anyone but there’s a cult in my area that apparently ‘brainwashes’ people | So to understand brainwashing, lets take a look at a child. Children are easily influenced by what they hear. If you tell a child to look both ways before crossing the road, they will most likely follow.
This extends out to adults. Some adults join cults as the cult has made a very persuasive argument, or influenced them in some way. Some people join because they're lonely and looking for a community, and some because they're well, not too bright.
Brainwashing isn't akin to how it's portrayed in movies. It's just using psychology on someone to figure out what they want and using that to manipulate them. | 13 | 18 |
ELI5: Baptist vs. Methodist vs. Lutheran vs. Presbyterian, etc. | I mean besides the general "Baptists tend to be more conservative" thing. What are the actual official differences in beliefs? They seem pretty interchangeable. | Okay, short answer is : Doctrine.
There is a continuum for religious doctrine that runs roughly from Arminian to Reformed. This has to do with how they believe we react to God. Armenians believe we continually choose to go to heaven or hell, and can decide to be with God or to stray at any point. Reformed Calvianism is the other extreme, that God chose whom he will send to heaven and hell, and only died for certain people for his own reasons. There is an acronym for this called TULIP that details this doctrine
Methodists are closer to arminian
Presbyterians are closer to Reformed/Calvanism. They believe in infant baptism, (because God picked you anyway) Baptists are horrified by this because you didn't make the choice to turn from your sins and follow God via faith in his plan for salvation.
Baptists are very broad doctrinally and are governed by the southern baptist convention, believing in baptism as a demonstration of salvation. They are relatively centrally located on the aforementioned continuum. evangelism is their focus, and they concentrate on spreading the gospel (the good news that Jesus died for your sins so you can go to heaven.
Lutheran is in line with the reactionary teachings of Martin Luther. All of these denominations believe you go to heaven by faith, not by what you do (i.e. baptism, obedience, communion), but the lutherans are focused on this; and an individual faith with God. as such, they lie in the middle territory overlapping much of the Baptist beliefs. Salvation is for all, which is contrary to TULIP presbyterians.
One branch is not necessarily more conservative than the other. United Methodists are VERY liberal, and primitive Baptists are weapons grade conservative, but and evangelical methodist is more conservative than an American Baptist Church
Conservative -> believes the bible
Liberal -> Bible's a nice guideline, not necessarily all real or literal
The real difference you should know with protestants is evangelical vs. mainline
Evangelicals (Some baptists, non-denominational) tend to be more theologically conservative, but less formal in church settings. they tend to have "megachurches" with rock bands and focus on spreading the gospel. These churches are maintaining numbers and even growing in some areas of the country, which you would expect since they are always telling people about Jesus.
Mainlines (lutherans, methodists, presbyterians) tend to be more theologically liberal, but more stodgy in execution. they focus on church history, sing hymns and you'd rarely catch jeans in a Sunday service. They are dying demographically, as they are predominately old and white. They don't focus on outreach for spreading the word, but are often active in community service. | 110 | 267 |
ELI5: Differences Between Soft Water and Hard Water | ​ | Hard water: lots of minerals (typically calcium and magnesium) dissolved in the water.
Soft water: less minerals dissolved in the water.
Now, why does it matter? Because minerals dissolved in water can sometimes crystallizes and no longer be dissolved in the water. This process is called precipitation. If it does it in your pipe, faucet, shower-head etc, it can accumulate and damage the pipe and the faucet. | 38 | 28 |
[Marvel] How much stronger is Spider-Man when he has the Black Suit? | When he can bring himself to wear it at least? | It varies, usually between 2x-10x stronger.
Given the other material about how he's always holding back and how he routinely beats symbiote worn by others, the symbiote might not even boost his strength much at all. It might just be affecting his psychology to make him hold back less. | 51 | 38 |
How was Newton's gravity equation derived if we didn't know the specific quantities involved? How could you check your math with the evidence to verify it's correct? (Such as the masses of planetary objects or the distance between them?) Said another way, how did we compute the masses of planets? | In Newton's equation for the force of gravity, he derived
F = GmM/r^2
and then that has been used to calculate, say, the masses of the planets in our solar system as well as the sun. What i don't understand is how that was able to be accomplished considering you need all of the values except for one in order to solve the equation (for a specific value).
So, for example, if I want to know the mass of the moon, I need to already know the mass of Earth, its distance to the moon, the gravitational constant as well as the force of gravity between the two! Which quantities became known first in order to figure out these things?? | Newton actually didn't know the masses of the objects in the solar systems, because astronomically you can only measure GM, and he didn't know the value of G. Only like a hundred years later did someone manage to measure the gravity between two big lead balls of known mass and determine G from that; this experiment was known as "weighing the Earth" because it allowed people to find out the mass of the Earth.
What Newton did was to figure out that in general, an attraction that goes like 1/r^(2) produces elliptical orbits with the Sun at the focus. Since Kepler had already figured out that the orbits are elliptical (using Tycho Brahe's data), this gave Newton confidence that his law was right, even if he didn't know all the numbers. | 50 | 48 |
ELI5: Buddhism | The essence of Buddhism lies in the 4 noble truths.
1. The universe is imperfect by our standards. It doesn't conform to our needs. We experience discomfort and suffering. We call our experience of this imperfection "Dukkha".
2. Dukkha is caused by craving. We find the world's "imperfection" distressing because we want our needs and desires to be catered to.
3. By extinguishing craving, it is possible to escape the effects of Dukkha.
4. The Noble Eightfold Path leads away from Dukkha. The path is the method that makes up the spiritual practices of Buddhism. | 16 | 35 |
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Why isn't Ceres considered the main target for a manned space mission? | If we ignore for a moment the counterproductiveness of interplanetary human spaceflight why isn't Ceres deemed the prime candidate for such a mission? It clearly has some important advantages over the most frequently mentioned candidate, Mars:
* Ceres has much more frequent launch windows to/from Earth than Mars, one per 467 days in comparison to one per 780 for Mars
* it has a much smaller gravitational well, the gravitational acceleration on the surface of Ceres is only about 2.8% that of Earth
* its upper layers are very rich in water, it is thought that there is more water on Ceres than there is freshwater on Earth.
| 3 Main reasons
According to Wikipedia:
> The unmanned Dawn spacecraft, launched by NASA in 2007, is en route to Ceres. The probe has been orbiting asteroid 4 Vesta since July 15, 2011. After completing one year of explorations there it will continue on to Ceres, arriving in 2015, five months prior to the arrival of New Horizons at Pluto.[28] Dawn will thus be the first mission to study a dwarf planet at close range.
* We haven't had a chance to study it. NASA is very unlikely to send a manned mission to a celestial body that it hasn't had the opportunity to thoroughly study beforehand
* The Asteroid Belt is dangerous. Sending a probe to Celes is of no consequence, but it is very unlikely that NASA would be willing to risk the safety of its astronauts (and its budget) on such a mission with current technology.
* Distance. Celes hangs out at around 2.766 AU. Mars is at 1.523 AU. Current technology wouldn't be able to get astronauts there in a way that is practically and economically feasible.
| 62 | 101 |
ELI5:If we can build massive telescopes to gaze into space why can't we build massive microscopes to gaze further into the sub-atomic level? | Telescopes use light. That is a simple statement, yes, but it is important. Light is a particle, and it reacts with things as if it had a physical size - it's wavelength.
That wavelength is a few hundred nanometers. Trying to see atoms with light is like trying to see marbles by throwing basketballs at them, and seeing how they bounce off. We need smaller things - higher energy light, for instance, like X-rays, with shorter wavelengths, or tiny particles like electrons. With these, we can produce images of atoms and molecules.
TLDR: Light is too big. In order to see something, we need something smaller than it to see with. | 27 | 18 |
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CMV: It is irrational to expect mandatory child support and be pro choice. | The issue of abortion from the pro-choice perspective is that of a woman's right to sovereignty over her body. The issue of child support is that of the welfare of a child. They are entirely different discussions, and one has very little to do with the other. | 33 | 17 |
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ELI5: Why does oil seem most abundant in dry, desert areas and how did it get there in the first place? | In the case of oil, a special set of conditions has to apply for it to be formed and preserved in the subsurface:
1. Source of organic matter (marine plankton/algae ➡️shale)
2. Deep burial (heat and pressure) ♨️⬇️
3. Reservoir rock (eg sandstone)🍰
4. 3D Structure to trap migrating oil🗻
5. Seal to prevent it leaking out🔐
Much of the (now) desert area of the Middle East was a stable landmass for long periods of geological time where the 5 conditions could be met, resulting the giant fields that you mentioned!
But giant fields are found in many other areas as well as offshore - they are just often more technically challenging and expensive to produce
| 135 | 312 |
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ELI5, how come when you get an organ transplant, there's a chance your body will reject it and your immune system will kill it. But when you get infected by a new disease, it's difficult for your immune system to kill the disease. | When you get an organ transplant, your immune system can try to attack the organ, recognizing that it does not belong in your body. The same is true for infections. The difference is that an organ does not fight back, it does not try to spread and create more of itself.
It’s like the difference between getting into a bar fight (an infection) and going into a nursing home and beating up old people (rejection) | 128 | 49 |
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ELI5: Why do characters in games have a separated "graphic model" and a "hit box model"? Why can't the graphic model be used to detect hits? | There's probably multiple reasons, to start though hit detection can be expensive depending on the complexity of the model and the speed of the game (the faster things move the more often you have to check and the less time you have to complete that check).
The more complex the "hit detection" model, the more intensive it is to check. Take two spheres for example. If you know the center point and radius of both spheres, all you need to do is ask "Is the distance from center A to center B equal to or smaller than the radius of A + B?" If the answer is yes, the objects have collided. This gets slightly more complex with rectangles, but it's still pretty easy.
Now if you change one object to a polygon with 800 sides/polys (a very simply character model in modern times). You now have to check the position of all 800 sides to determine if it collided with another object because you don't have a single "center" for all polygons and can't simply check distance from a non-existent center. | 28 | 19 |
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Have any philosophers argued that "femininity" and "masculinity" are imaginary, are not biological and should not be linked with sexual dimorphism? And have any philosophers ever argued against "beauty is feminine, not neutral" and instead argued beauty is neutral and men are beautiful too? | I'm not talking about "wearing a skirt, dress, make up, etc is feminine!" or "being aggressive, wearing suits, lifting boxes, and being less emotional are masculine". I am talking about when people say "being tall, having more body and facial hair, etc are masculine!" or "being short, having smooth skin, having curves, having less body and facial hair, etc are feminine!!". They say a man with more delicate features, more curves, less body and facial hair, smoother skin, etc is a "feminine" man. And they say a woman with less delicate features, less curves, more body and facial hair, etc is a "masculine" woman. They basically mean "femininity" and "masculinity" are sexual dimorphism.
I had a debate with someone on reddit, and these are the things I was told: [https://imgur.com/a/5qDM5M9](https://imgur.com/a/5qDM5M9)
I said beauty is neutral, I call the sun beautiful, doesn't mean the sun is "feminine", but this person jumped down my throat and said:
>Beautiful is not neutral. Just because we can call the sun beautiful doesn't make it neutral when comparing humans.
>
>And why do you call the sun, paintings, etc beautiful? Because they are visually appealing. Same with women, they are better to look at than looking at men. Women are more visually appealing that's why beauty is feminine.
>
>No matter what you say, beautiful will always be a feminine thing.
>
>Female pornstars make more money. Female models make more money. Men are not beautiful, socially they are considered handsome. In humans, beauty is a feminine trait not a masculine one.
Men and women are also both attracted to the bodies/faces of women than they are towards the bodies/faces of men.
>
>Read this article: [https://www.psychologytoday.com/ca/blog/the-scientific-fundamentalist/201101/beautiful-people-have-more-daughters](https://www.psychologytoday.com/ca/blog/the-scientific-fundamentalist/201101/beautiful-people-have-more-daughters)
The article seems to say because beautiful people have more "daughters" than "sons", women become more beautiful and men become less beautiful (as the number of beautiful women outnumbers beautiful men), meaning beauty ends up being a feminine thing.
I forgot to mention these two Quora answers also said "beauty is aligned with feminine, the definition of "beauty" includes qualities that men lack, especially the older they get. Smooth skin. Delicate features. So men that are beautiful have feminine traits": [https://imgur.com/a/yP831J7](https://imgur.com/a/yP831J7) Imgur
>This has to do with a few things: "Beautiful", is a term that itself more aligned with the feminine.
>
>"Handsome" is the term that is aligned with men.
>
>When you see a man that is "beautiful" (small, soft facial features, shorter, thinner) it tends to mean he attractive in a way that is not masculine but rather feminine. This type of quality is rare, and causes our brain to be stimulated by the unusual appearance. Likewise, when we see a "handsome woman", or a woman with masculine features (tall height, sturdy build, strong jaw, long fingers, large feet, etc) we will be equally intrigued.
>
>Part of the definition of "beauty" is that it includes qualities that men lack, especially the older they get. Smooth skin. Delicate features. No pronounced jaws or brow ridges. Men get craggy faces, large pores, and start to grow hair in unfortunate places.
Are there any philosophical arguments against what these three people (the two on Quora and the one on reddit) said?
I argued "femininity" and "masculinity" are social constructs but this person said:
>No you are wrong. Femininity and masculinity exists, its not a social construct. It's a biosocial construct involving both variance in hormones and environmental inputs. A woman with high estrogen will be more feminine than a woman with low estrogen, and a man with high testosterone will be more masculine than a man with low testosterone. It's biology but also involves social feedback.
>
>Testosterone and estrogen is biological way of explaining traditional masculine and feminine traits. And how much of it goes up or down in response to environment is mediated by social feedback.
Have any philosophers argued that "femininity" and "masculinity" are imaginary, are not biological and should not be linked with sexual dimorphism? And have any philosophers ever argued against "beauty is feminine, not neutral" and instead argued beauty is neutral and men are beautiful too? | >Have any philosophers argued that "femininity" and "masculinity" are imaginary, are not biological and should not be linked with sexual dimorphism?
Judith Butler says something along these lines.
>And have any philosophers ever argued against "beauty is feminine, not neutral" and instead argued beauty is neutral and men are beautiful too?
I can't think of a single Philosopher who has ever argued that beauty is a exclusively feminine trait. | 70 | 43 |
I genuinely suck at 'coding' and I don't know what to do | I put coding in quotes bc it's not coding. I'm a junior in HS taking AP Comp sci principles which uses [code.org](https://code.org) which is literally scratch. I cruised through the beginning and now I'm stuck. I have to build an app using 3 data sets and a traversal and I sort of have an idea, and I can sort of break it down into smaller pieces, but I don't know how to actually make it into code if you know what I mean. I figured I would ask yall if there was a mindset or something you have to learn because programming is probably what I'm going to major and work in. | The vast majority of it is practice. A lot of things come with experience, like knowing what you can do, what tools are available, whether a problem looks like something you've done before, etc.
That said, there are a few techniques that your really need to get down as a beginner. The big one is thinking algorithmically. You have a problem. What do you need to do to get to the solution? Start in vague terms, describing a handful of steps that you need to take. Now you have a handful of simpler problems. Repeat the process until you reach the atomic solutions that your language gives you.
In order to help guide that process, it's helpful to know what those atomic tools are. What kinds of instructions can you give.the computer? Depending on the language, you probably have some basic math, some simple manipulations of text, some sort of conditional execution, some way to repeat the same steps, etc. | 36 | 43 |
ELI5 : what causes people to have nightmares | I personally have a lot of nightmares. Very frequent.
So what caused people to have them and why do some have them more frequently than others? | It is hypothesized that dreams are a way of preparing you for dangerous and/or scary situations. Frequency and intensity of nightmares correlates with levels of stress. We all dream each night, but you will be more likely to remember them if you wake up during the dream.
Also - parasomnias (sleep disorders) | 102 | 162 |
ELI5: How do fighter pilots know when an enemy has them "locked on"? | Is that ominous buzz Hollywood or reality? | There are systems on the plane that can detect when a (potentially, but usually) hostile radar signal is frequently pulsing the plane directly.
Other alerts are displayed/sounded if there are similar signals in the area, but not necessarily pulsing off of the plane directly. | 19 | 20 |
CMV: Deafness is, and should be, considered a disability. | Let me preface this by saying I do not have ANYTHING against deaf people, and that I don't think having a disability of any kind makes you any less of a person.
​
The word disability has multiple definitions, but the one I've come across that fits best here is: " a physical or mental condition that limits a person's movements, senses, or activities."
​
Deafness is a condition that not only limits a person's senses, in most cases it completely gets rid of a sense. I don't see how this can be anything but a disability. Deaf culture is a wonderful one, and I love reading about it, but if everyone in wheelchairs formed a culture of their own and started claiming they weren't disabled because of it, this would be met with extreme skepticism.
​
Again, I want to say having a disability does not make you any less of a person. I know many deaf people are proud of their deafness, and not only is that okay, it's wonderful! but that doesn't change the fact that deafness is a disability, as it completely removes one of the most important senses in the human body.
​ | > a physical or mental condition that limits a person's movements, senses, or activities
Should a person still be considered disabled if they find solutions that alleviate the consequences of these conditions? What if the impairment has no remaining significant effect on their current standard of living? | 12 | 108 |
Why is ethanol drinkable but methanol, 2-propanol, etc. poisonous? | From an organic chemistry perspectice, what significant difference does one extra carbon make? I'm an organic chemistry student and I've yet found the answer. | From the point of view of organic chemistry, one extra carbon could make little difference (usually it does not, anyway), but from the point of view of biochemistry, even one chiral center makes a huge difference, let alone one extra carbon.
Acute methanol poisoning is extremely dangerous because it is converted *in vivo* to formaldehyde and formic acid, both of which are extremely toxic for the retina, and boom there goes your sight, forever. The toxicity of ethanol is exceedingly lower, because human metabolism can take care of its byproducts (though the intermediate oxidation product, acetaldehyde, is probably a carcinogen). Isopropyl alcohol, while not being something you should drink, is not really bad like methanol: it is converted *in vivo* to acetone, whose toicity is also relatively low. | 36 | 40 |
ELI5: Why does smoking interfere with healing and how does it interfere? | Smoking narrows the bloodvessels which are essential to recovery. Narrow vessels transport less blood, less blood means less O2 and other minerals. In other words, recovery takes longer when you're smoking. | 30 | 44 |
|
ELI5: How do “hostile takeovers” work? Is there anything stopping Jeff Bezos from just buying everything? | Normally, when one company wants to buy another, management approaches the target and they begin discussions. If the target does not want to sell for whatever reason, they can tell the acquirer to go pound sand. If the acquirer really wants to, they can do a hostile takeover if the target is publicly traded and get the financial backing in place and go to the public markets and just start buying large blocks of stock. Once they own enough, they can get a board seat and influence the target or just keep buying and force them to give in. | 12,032 | 16,674 |
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I want to store values of a 2D array into a 1D array in java. | I want to convert 2D coordinates into a 1D array. I've created an n by n 2D array. I then want to assign values of 1 through N into the 2D array sequentially from left to right, and then return the new 1D array.
private static int[] to1Dcoords(int row, int column) {
grid = new int[row][column]; //creates n by n grid
int temp = 1;
for (int i = 0; i < grid.length; i++) {
for (int j = 0; j < grid[i].length; column++) {
grid[row][column] = temp;
temp++;
}
}
int[] in1Dcoords = new int[grid.length()];
for (int i = 0; i < in1Dcoords.length; i++) {
in1Dcoords[i] =
}
}
Any help would be much appreciated!
&#x200B; | You have some syntax errors in your code, but I'll concentrate on your question.You can just loop over your 2D array and assign values to a n*n length 1D array:
int[] array1D = new int[n*n];
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
array[i+n*j] = grid[i][j];
}
} | 11 | 15 |
CMV: Overpopulation is a myth. | Pretty simple - the planet Earth is not overpopulated and (given current demographic trends) never will be. All of the problems that are blamed on 'overpopulation' are not population problems and have much easier and humane solutions than limiting population. The idea of 'overpopulation' is rooted in racism, classicism, nationalism, and consumerism and unfairly targets the poor, people of color, and historically-exploited populations. Here are the reasons I hold this view.
* **The total Global Fertility Rate is dropping.** Fertility rate is, simply, the number of children a woman has. Since every child requires a male and a female person to exist, the *ideal* fertility rate is 2.0 children/woman. However, some people (biologically) can't have children, some will choose not to have children, and some children will die before sexual maturity. Therefore, in the real world, the fertility rate must be somewhere *above* 2.0 children/woman to compensate. In developed countries with low levels of child mortality, the ideal fertility rate is around 2.1 children/woman, but in developing counties (due to war, famine and inadequate medical care), it's closer to 2.3 children/woman. **The total global fertility rate for the 2010s (so far) is 2.36 children/woman**, and has been consistently falling since the 1950s. If 'overpopulation' *was* a problem, it seems we've already corrected it.
* **Distribution and consumption of resources is not a population problem**. If you look at [this page](http://en.wikipedia.org/wiki/List_of_sovereign_states_and_dependent_territories_by_fertility_rate) (or even the graphic at the top) it becomes obvious that the vast majority of the world has a fertility rate below 3.0 children/woman. Further down, you see that most (if not all) developed countries are below the basic replacement rate of 2.0 children/woman. The countries whose fertility rates are above the 2.3 ideal replacement rate are overwhelmingly poor and developing nations: whose citizens consume *far*, *far* fewer resources than the citizens of 'developed' nations. I've seen several figures about how much citizens of Western nations consume relative to developing nations, but lets simply say that Westerners consume far more energy, food, and natural resources compared to their global peers. If Westerners had fertility rates similar to Niger or Mali, we might have problem, but the populations of Western countries are stable (or shrinking) and 6 kids in Sub-Saharan Africa consume fewer resources than 3 kids in the US or UK. It's pretty rich to tell poor people in traditionally exploited countries that they should stop having kids so that Westerners can suck up a disproportionate amount of resources.
* **If population rates continue to drop, we're going to need citizens from high-growth countries to supplement our workforce.** Look to Japan as a a country on the verge of crisis. Japan's fertility rate in 2012 was 1.4 births per woman - far too low to sustain their aging population. Japan's work culture is notoriously strenuous, and demand for social services for the elderly is beginning to outpace tax revenue from workers. Most, if not all, Western countries are facing this impending crisis. The only reason that the US has staved it off is our robust immigration tradition. In the future, we will need immigration from high growth countries to fill vacancies in our workforce and pay the taxes that will support our social structure.
* **The carrying capacity of the Earth has often been guessed at, but never reached.** In just over 100 years, we've gone from 1,000,000,000 people on earth to over 7,000,000,000. And yet, we haven't experienced major global famine, resource wars, or wide-scale poverty. In fact, as our population has grown, the standard of living of *most* people on Earth has *risen* to unprecedented levels. Even the people living in the worst extremes of poverty have seen their standard of living increase from where it would have been 100 years ago. Is there a theoretical 'breaking point'? Of course: but we'll never reach it. Because standards of living directly correlate to lower fertility rates. As education, women's rights, and availability of consumer goods increases, fertility rates drop. People with access to contraception and medical services that prevent child mortality will necessarily have fewer children. And people who can work for more than just subsistence have fewer children so they can increase their standard of living. The answer to overpopulation isn't to somehow prevent people from having kids: it's to give them the goals and tools to better their lives.
Based on global fertility rate trends, the Earth's population will peak in 25 years at around 10,000,000,000 people. The current generation of under-15 year olds will be the last largest in human history. The post-Millennials will have fewer children than their parents, and their children will have fewer children still. By 2075, the earth's population will be back at 7,000,000,000, with all the technological and ecological advances we've made. Likely, the population will continue to drop from there. This will, undoubtedly, cause a whole host of problems, but those are for another CMV.
Overpopulation is a myth - we have many problems on this planet, but the overall number of people is not their cause. Our human society is prosperous and getting better all the time, despite population growth. Growth trends only have another 25 years or so until they start declining, bringing with them a whole host of new problems. Trying to control population is a ham-fisted approach to the problems of resource distribution, pollution, poverty, natural-resource usage, and national politics - all of these issues can be solved more directly and humanely by addressing them directly and not circuitously by attacking population numbers.
CMV.
_____
> *Hello, users of CMV! This is a footnote from your moderators. We'd just like to remind you of a couple of things. Firstly, please remember to* ***[read through our rules](http://www.reddit.com/r/changemyview/wiki/rules)***. *If you see a comment that has broken one, it is more effective to report it than downvote it. Speaking of which,* ***[downvotes don't change views](http://www.reddit.com/r/changemyview/wiki/guidelines#wiki_upvoting.2Fdownvoting)****! If you are thinking about submitting a CMV yourself, please have a look through our* ***[popular topics wiki](http://www.reddit.com/r/changemyview/wiki/populartopics)*** *first. Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | You're looking at overpopulation from a global perspective when you shouldn't be. It needs to be looked at on a regional level, especially concerning logistics of distribution an consumption of resources.
On a global level, we sure do have enough space for people to live, to grow food, harvest resources, etc. But a lot of good it does a country who needs wheat when they live in the desert or a country that needs steel but lives in an area with no iron deposits.
If you want to see some examples of overpopulate in terms of living space, just look at India. Heck if you're an American just look at the homes the Japanese live in and compare it to the average American home. | 298 | 368 |
[Resident Evil Village] Who spread the info around that Chris punched a boulder in a volcano? | Heisenberg makes reference to that in your fight against him. I don’t think Chris or Sheva would go around mentioning that to everyone. | Several possibilities for that information to get out:
1. Chris most likely included it in his mission report and may have mentioned it in his debrief.
2. Sheva, after returning to the BSAA West Africa branch, also included it in her mission report/debrief and being that she was rescued in the most cartoonishly bad ass way, most likely tells her coworkers the story of how Chris punched a boulder into a river of lava to create a stepping stone for her.
3. Chris, in an attempt to inspire new BSAA recruits and increase morale, tells them the story of how far he's willing to push himself to not let people die. (Ironic since he loses his squads in almost every game he's in with the exception of important characters) | 43 | 35 |
what has caused the massive cost of college and higher education | [https://content.attn.com/sites/default/files/weeksoffulltimework\_1.png](https://content.attn.com/sites/default/files/weeksoffulltimework_1.png)
college costs have not kept up with inflation.
is it mostly due to federal student loan programs as this NBER study says?
[https://www.nber.org/papers/w21967](https://www.nber.org/papers/w21967)
" We measure how much changes in underlying costs, reforms to the Federal Student Loan Program (FSLP), and changes in the college earnings premium have caused tuition to increase. All these changes combined generate a 106% rise in net tuition between 1987 and 2010, which more than accounts for the 78% increase seen in the data. Changes in the FSLP alone generate a 102% tuition increase, and changes in the college premium generate a 24% increase. "
[https://www.newyorkfed.org/medialibrary/media/research/staff\_reports/sr733.pdf](https://www.newyorkfed.org/medialibrary/media/research/staff_reports/sr733.pdf)
" We study the link between the student credit expansion of the past fifteen years and the contemporaneous rise in college tuition. To disentangle simultaneity issues, we analyze the effects of increases in federal student loan caps using detailed student-level financial data. We find a pass-through effect on tuition of changes in subsidized loan maximums of about 60 cents on the dollar, and smaller but positive effects for unsubsidized federal loans. The subsidized loan effect is most pronounced for more expensive degrees, those offered by private institutions, and for two-year or vocational programs " | The concluding remarks of the document you shared are pretty concise - the cost change was most pronounced in colleges that got advanced knowledge of the increased loan amounts students would get. Also in private(not state funded) and/or competitive institutions. Student loan amounts changed to account for inflation or increased costs like cost of living.
In response, schools changed the cost to max out the money they would earn from students using loans to go to school. So you could interpret it multiples ways. Acknowledge the mismanagement of the federal loan programs, and not predicting that colleges with prior notice of spending increases that they would increase their prices to make more profits. Acknowledge that the schools are being greedy and taking more money for pure profit at the expense of the students and the government. It’s unfair to say though the loan programs themselves are a bad idea and program itself caused the skyrocketing tuition costs. The school costs should have been regulated and honestly higher education should be regulated so students aren’t tens of thousands of dollars in debt so that big schools can have their football stadiums. Lending a little bit of money to low income students at the beginning of the program so they could reasonably afford to live and succeed at college is different than the monster the mess has turned into. | 32 | 118 |
Is there like a guide on programming languages? As in what works best for what kind of project? | I have a somewhat solid understanding of some programming languages, but I’m having some trouble which language might be better for a type of project. As in like, is python better for a simple chess game than Java. | As always with any “Engineering” question which is what this is, the real answer is, it depends.
Most answers should be “go with what you know best” so if you know python then use that.
Thinking about your project up front can dictate what technologies you use including language.
Is a static type system important,
Will you want functional programming and/or Object oriented programming.
Will you follow a design pattern or grow the program organically as you add features.
There’s a bunch of options and bunch of trade-offs to consider.
In terms of languages they are all Turing complete which means (loosely) any program can be written in any language.
Obviously certain languages are geared towards different things like where/how they are deployed, or performance etc. | 24 | 50 |
ELI5:On an atomic/molecular level, Why does glue glue? | Why does glue glue and adhesive adhere on a micro scale.
I understand the larger picture of surface area, surface texture and general bonding along with curing. But what is happening that allows the glue to bond at an atomic level.
| There are a few theories, and it depends on the glue, but you already have a fair understanding of the basics: surface area.
Nothing is really smooth if you zoom in enough. There are valleys and ridges and bumps and holes. Now imagine 2 rough surfaces like that being placed together: nothing much will happen. But now fill in those gaps with something runny that will get into every crack and tiny space. When that stuff dries it isn't just a uniform shape like a zigzag that can easily lifted off another zigzag, the ridges and valleys are much more complex, and are in 3D and go in every direction, more like the branches on a tree. If you try to pull the glue out it won't come easily because some valleys or shafts might go left, some might go right, some forward, some back. Some might be straight, some might curve, but they are all filled with glue that would need to be pulled in every direction at once to come out of these spaces. Now that's only one object, the item you're sticking it to also has the same properties, so the glue is really getting into all these tiny spaces on 2 items, meaning they are then harder to come apart.
Another way glue can work is that atoms have positive and negative charges like magnets, and so like lots of tiny magnets they can actually kind of stick together. | 24 | 25 |
ELI5: Why are the glasses shaped differently for red and white wines? | Red wines tend to have stronger flavor compounds and tannins that soften when they "breathe" or decant. The wider bowl of a red wine glass is believed to allow for more contact with the air, which means these soften a bit more and allow a greater distance from your nose to the wine so that the aromas aren't so intense. The widest red wine glasses are Bordeaux glasses, because a lot of Bordeaux are high-alcohol and high-tannin, so the very wide shape allows both of those to mellow out much more.
White wines, on the other hand, tend to be a bit softer with less intense flavors - the smaller size is because they don't usually need to breathe, and they let your nose get that little bit closer to pick up the subtle aromas. Many white wine glasses also have slightly longer stems, because white wine is often served chilled, and that keeps your hand away from the bowl so that you're not warming up the wine with the heat of your hand.
At the end of the day though, these are minor things and they're all generalities. I've had people insist on serving specific white wines in wider red wine glasses because they were higher-alcohol than is common, for example. And there have been studies that show that for most people, the difference is negligible between glasses, and even for experts there are disagreements about the "best" glass for a particular need. | 54 | 26 |
|
ELI5: Why do some people find it hard to eat enough, while others over-eat? | It seems like such a basic function but to me eating three times a day, let alone five, every single day of my life is such a chore. I find it hard to imagine that to most normal people it isn't even something they need to consciously think about.
Is there a reason for such disparity in such a basic human function? | Leptin sensitivity, insulin sensitivity, ghrelin and other hormones cause different appetite levels for different people. That's an oversimplification but basically leptin is one of the main hormones that puts the "brakes" on hunger. Thinner people have high leptin sensitivity and therefore recognize feelings of fullness more readily after eating. Overweight people develop resistance to leptin, leading them to feel hungry for longer. | 43 | 45 |
How do the body regenerate the stomach acid after we've vomited? | How long does it usually take and (providing I've essentially emptied my stomach), how long should I wait until I eat again? | Parietal cells in the gastric endothelium (cells lining the stomach) produce acid (HCl) in response to various signals, including changes in stomach pH and hormones like histamine and gastrin. The amount of time varies a lot, but eating after vomiting won't probably hurt you, though you might vomit again. The stomach will naturally increase production of acid and digestive enzymes in response to any food you put in it. | 25 | 28 |
ELI5: Why does your vision continue to spin even after you stop spinning? | You know, you get in a swivel chair and spin around really fast and then stop but you're vision still seems to "spin"? Is my brain catching up or something? | Our sense of balance, motion, and direction come from what's called the vestibular system, which is located in our inner ears. Part of this system is 3 small tubules filled with fluid. When when move or spin or change directions, this fluid moves as well, and our brain interprets those signals to determine our orientation and acceleration, sort of like a gyroscope.
When we spin real fast, that fluid in the tubules spins too, and when we stop suddenly, it takes a few seconds for the fluid to stop. Think of it like stirring a cup of coffee. Even after you stop stirring, it takes a few seconds for the coffee to stop swirling and come to a stop. The same thing happens in our vestibular system. Our eyes see us motionless, but our vestibular system tells us we're still spinning, so it causes momentary dizziness until balance in restored. | 78 | 157 |
Why do we use 1/12 of the mass of carbon-12 to define what is the value of u, instead of the mass of hydrogen-1? | H = 1 _was_ the original scale used by Dalton, but O = 16 has also been used historically as oxygen was a common lab reference material. Different countries adopted either or both scale for whatever historical or cultural reasons. However, when new isotopes of oxygen - O-17 and O-18 - were discovered, the scale is found to be slightly off, as samples of oxygen can vary in weight depending on isotopical composition. Not only that, the old scale was largely adopted by chemists, while the "pure" O-16 = 16 scale was common amongst physicists.
Because carbon-12 was already a common standard reference for mass spectrometry, it was a good compromise for everyone when IUPAC finally decide to settle on a unified scale. | 12 | 15 |
|
What properties of Glass can change light to be manipulated by magnetism? (Refer: Faraday's light experiment; COSMOS) | COSMOS is a big hit, and watching it is vastly entertaining, even though It's all things that I've heard before(Or at least that's what I thought). However the show goes along in one of its episodes concerning Micheal Faraday's experiments with magnetism. This situation comes to light(no pun intended)
"Becoming desperate he tried his glass brick that was a souvenir of when Faraday worked for Davey. It worked!!"
Refer to COSMOS: A Space Time Odyssey (2014):Time stamp: 22:55(overview) 24:50(specific), but link here: http://www.cosmosontv.com/watch/250569283639
So as the story goes, Faraday picks up a glass brick, and passes polarized light thought it, while the light is in a magnetic field. This twists the light waves into a different orientation(polarity?). This attempt worked, despite the usage of a vast amount of other transparent and translucent materials.
So I want ask, what's special about glass to cause this to happen? And What exactly is happening?
COSMOS didn't explain this with any detail, but it was the most curious event to be talked about in the episode and I'm interested in knowing more. | The property of the material used in the Faraday effect is something called *birefringence*. You might be familiar with the property of bulk material called the index of refraction, it is a number that describes how the wavelength (speed) of light changes inside a medium as well as what the name suggests: how much light refracts passing between two different media.
It turns out that materials can have a *polarization dependent* index of refraction that we call birefringence. What this means is that an electric field that is polarized one way sees a slightly different index of refraction than an electric field that is polarized in a different direction. Many materials have this property because of their internal structure but the difference tends to be really small. However even in materials that do not have this static birefringence in the presence of a magnetic field all materials will exhibit some (tiny) birefringence.
For the Faraday effect we use this birefringence. In the presence of a magnetic field the glass exhibits a polarization dependent index of refraction. Now an electric field passing through the material will see a different index of refraction for different components of its polarization. Because the index of refraction tells us how fast light travels inside a medium the net effect is that a component of the electric field can lag behind a different component of the electric field. This lag is what causes the rotation as the electric field passes through the material.
EDIT: spatial dependent ---> polarization dependent | 17 | 121 |
ELI5: Why are movies so quiet during normal dialogue, yet so loud during music score or action scenes? | Constantly changing the volume is annoying. It seems pretty much all movies made in the last twenty years or so is like this. | The movie sound recording is mixed for use in theaters, which have different standards for audio levels, having a large dynamic range. Its an artistic choice of sorts, to give impact to loud sounds like explosions, gun shots etc.
They could of course remaster these levels for home audio, but they don't because it costs money. You can fix this somewhat if you have a surround setup by boosting the center channel volume from your amplifier, where most vocals are panned. Its worse however if you just use the TV or a 2 channel system, because the center channel becomes a virtual channel only (it plays identical sound through both speakers, making it sound as if its centered). While boosting a virtual center channel is technically possible, it requires digital sound processing that would add cost to any playback device.
| 13 | 27 |
I'm going to University in September (UK) to study Economics and am planning on learning some form of coding over the summer as I have a long break and want to do something productive. Does anyone have any advice on what would be the best language to learn that would be applicable to my degree? | I studied in the UK and we used Stata and R/ R studio Highly recommend the latter as it is free therefore easy access for you and your university and any potential employers which makes it very popular! | 72 | 131 |
|
ELI5: why are scientists trying to clone a wooly mammoth using ancient DNA when they could be cloning endangered animal species, such as the white rhino, whose DNA we can still collect? | As has already been said, there are research efforts focused on both. However, tackling the technical challenges of piecing together a genome that hasn't existed for thousands of years would benefit the scientific community more than trying to keep a species alive that nature can no longer support. Sequencing the mammoth genome would represent a major achievement in our ability to study the genetic content of extinct species and could ultimately lead to greater insight into the origins of cellular life. This is the reason it gets more funding and media attention. | 144 | 490 |
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ELI5: I am living in a building where we are several students with one room each and we share a kitchen. How is it possible that all our keys to our rooms fit the lock to the kitchen, but not the other student's rooms? | Everyone have a key that fit the lock to their own room and the lock to the kitchen, but not to the other student's rooms. | A lock has a number of tumblers, which all need to be pushed to a certain height in order for the lock to turn. Each key is unique, and the bumps on the key correspond to the heights of the tumblers within the corresponding lock.
Imagine keys and locks as a 6 digit password. Now imagine that your kitchen lock is only a 4 digit password - the kitchen lock only has 4 tumblers, not 6. So your keys can all open the kitchen door if they have the right 4 bumps, but you can't open each other's doors.
Imagine the kitchen door is 0134. Imagine your door is 013461 and your roommate's door is 013413. You and your roommate can both open the kitchen because your keys have 0134 (which is all the kitchen needs,) but you can't open each other's doors because your keys don't match the lock. | 1,350 | 368 |
ELI5:How does insurance assign value to the body part of a musician? | Insurance is always, ultimately, based on the value of what will be lost. In the case of a musician, what's lost is the revenue generated from sales of their albums or music, or wages from playing gigs. This is actually pretty similar to how insurance handles a totaled car - a used car doesn't have a specific, set value, it depends on the exact condition of the car, the mileage, the make, model, and year, the area you're in...a thousand factors. But they can *estimate* the value based on how much similar cars have sold for.
Likewise, insurance companies can look at the past sales (or wages) of that musician and compare it to similar musicians and estimate how much the insured musician *should* make during the course of their career. That's how much they pay out in the event of an injury. Really, when you hear that a musician's arm or throat, they're insuring their *career* which is dependent on that body part.
Based on the projected payout and the likelihood of having to pay out, and based on the income from other people paying into insurance plans, the company has a baseline price to use for negotiation. | 12 | 22 |
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European Master's Advice: 1 Year MSc or 2 Year MPhil | Hi everyone, this is my first post on Reddit as a whole and I apologize if this is not the appropriate thread.
I am currently an international (Asian citizenship) second-year student in an Economics programme at a globally Top 50 university in Europe. Our economics programme is three-years long and has a math-intensive approach. My long-term goals are to attain a PhD at an American university (preferably in East Coast) to either enter academia or join an international organization (IMF, World Bank, etc). My current GPA is respectable (equivalent to a 3.7+ in the US scale), and I am planning on signing up to be a research intern at the university this summer as well.
I believe I can maintain my GPA and have decent extracurriculars (volunteering and data-related work), so I am looking at universities where I can get a scholarship for the Master's (financial conditions are okay, but saving money is appreciated). Based on my understanding, terminal MSc.'s in the US are not really meant for people that want to continue in the research-oriented world (and also have a reputation for being cash cows), whereas getting accepted directly into a grad school as an international is quiet rare, and though I think I have a good portfolio overall, I am not a prodigy-type student who will buck the trend.
Because of these reasons, I am more inclined to continue studying in Europe as most top-ranked universities (LSE, Bocconi, Barcelona GSE, etc.) offer scholarships to internationals and have pretty good placement records in both international organizations and universities. However, they differ in terms of the length of the programs they offer; Bocconi, Tinbergen and Stockholm SE have intensive 2-year programmes whereas Barcelona GSE and UvAmsterdam have one-year programs. Based on the program descriptions, the one-year programmes focus more on coursework and educating the students about theories and all while the two-year programmes incorporate an internship and/or research opportunity, which may be helpful as related experience on the resume when applying to PhD programs. With all that in mind, I would like your opinion about which type of education is more suitable.
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Additionally, if you have any other schools to recommend, please do let me know. Thanks Reddit :)
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TL;DR -- Undergradute economics student who wants to get a PhD in the United States wanting to know if two-year research intensive MPhil programs in Europe are worth the extra year compared to similar one-year MSc. | If you are set on an M degree, go to the place with the best international “name.” The US academy only sees reputation based on historical prestige.
Source: American with European MSc and American PhD. | 11 | 18 |
ELI5: In theory, how do all of the US government armed forces (Police, FBI, DEA, etc) rank and compare to each other? | Just walking around Penn Station, NY today, i saw..
- Over 5 army fatigue-clad guys standing around holding gigantic assault rifles / machine guns..
- Equally heavily armed "Homeland Security" police
- Standard NYPD guys just walking around
This just got me wondering. There are so many different authorities out there, I'm wondering how they rank? Off the top of my head, I can think of:
- nsa agents
- secret service agents
- cia agents
- fbi agents
- homeland security
- Military Police
- DEA agents
- US Marshals
- State Police
- Local Police
I'm going to make up a scenario.
Lets say you had 2 armed officers from each of these categories, standing around at a government banquet in the middle of a place where you can't call back-up very easily. Suddenly, there's a crisis situation! Maybe terrorists attacking, Die Hard style, or something.
Who instantly has like the most authority? Does it even work that way? How many of them could arrest a civilian if they needed to? If they needed to work together, would one of them 'officially' have the most authority to coordinate them?
Is there any kind of heiarchy to all of this? I'd really love to know who has the most sway, the most power, and in any kind of emergency situation, who ranks above who else.
EDIT: I'm specifically referring to the ARMED AGENTS for these different forces. For example, I've read the NSA/CIA (etc) all have armed personnel who work specifically for them. | They all have different responsibilities. The Federal level is above the State. And the State level is above the Local. State level in most states acts as a sheriffs department which is just like your local police, but across the entire state and used often for rural areas that do not have a local police force.
In the case of a terrorist attack, the FBI, the CIA, the NSA, and Homeland Security would all work on the locating the perpetrators, figuring out how they did it, and if there is any other imminent threats.
The CIA would most likely work on gathering intelligence about the chain of command across the world, taking them to wherever the idea of the attack developed. The NSA would start gathering intelligence domestically through wiretaps. The FBI would do more of the foot work in investigating the actual scene and probably do some intelligence gathering of their own. Homeland Security would start investigating who the people were by checking immigration records and other international criminal activities associated with the event. Homeland Security also controls the TSA at the airport, so they would be responsible for figuring out how the terrorists were able to avoid any detection at the airport when first coming to the US and if they were on any warning lists, like the do not fly list.
For example, if a murder happened in a city that has a local police force they will be the first to the scene. If the crime involves a larger matter, like a series of murders that goes across state boundaries, then the FBI would take over. The more complex and spread out the crime the more likely the local police would hand off the case to the FBI. The local police usually remains to provide local assistance and lower level investigation (door to door questions, local probes, etc).
**Intelligence -** There are 16 intelligence elements in the United States that are supposed to work alone and together. The over-arching umbrella over these 16 elements is led by the Director of National Intelligence.
NSA and CIA. The NSA is under the Department of Defense. The CIA is an independent agency, but they are all suppose to report to the President with daily briefings and to work together, especially after 9/11.
**Department of Justice -**
Federal Investigations: FBI
Drugs: DEA
US Marshalls: More or less the police for the Courts. They handle warrants, transporting prisoners, track fugitives
**Homeland Security -** Responsible for protecting the citizenry from a terrorist attack before it happens
Secret Service: Protects the current and past president's and their families, as well as foreign dignitaries. They are also responsible for preventing the counterfeiting of US currency and US treasury bonds notes.
Many others: TSA, Immigration and Customs Enforcement (ICE), Citizenship and Immigration Services, Customs and Border Protection.
Edit: Changed state level police per the comments below. | 12 | 45 |
Why is glass translucent/transparent? Is it a molecular arrangement thing? Is all clear matter clear for the same reason, such as water and diamond? | In general: Because there is no transition between an occupied and an empty energy level that corresponds to the energy of the light you consider (here: visible light). If there is such a transition, an electron can absorb the photon and reach the higher energy level, but if that process is not possible then the material will be transparent. This is not a binary thing - in general all materials will absorb *some* light, this includes glass and water. A few meters of glass or a few hundred meters of water are barely letting any light through.
The energy levels mainly depend on the molecules in the material and a bit on their arrangement. | 17 | 21 |
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ELI5: How does a smartwatch get heart rate using "green light" underneath the watch. | Is it also accurate? How does result compare to an actual blood pressure machine? | That green light illuminates the skin, measuring changes in blood volume in the capillary vessels. They don’t really measure blood pressure, they measure pulse, and some level of VO2 (volume of oxygen moved through your system when exercising). The pulse I’ve always found to be accurate, and the VO2 max is also relatively close. Other metrics I’m not sure on yet. But the green light isn’t much different than the finger clip pulse-ox light that is routinely used in medical care | 17 | 19 |
What is (Wittgenstein's/Dilthey's) 'Lifeworld'? | I came across something in a paper, recently: "Here, ‘Life’ is not to be taken in a biological sense, but in the one intended in Wilhelm Dilthey’s use of ‘Leben’ – Life as what he and others, including Wittgenstein, refer to as the human ‘lifeworld’ or the human ‘form(s) of life’."
What is this 'lifeworld'? I've googled and can't seem to get a clear understanding. Is it kind of like Heidegger's notion of World? A sort of phenomenological pre-condition, the world as we experience it?
Thanks :) | The world as people experience and live in it basically. Your life world isn't the (purportedly) objective world of the sciences, but a specific world shaped by your understandings and subjective views. Different people then can literally live in different life-worlds so to speak. Although there is an intersubjective element to it too. | 15 | 22 |
CMV: The companies that sell essential oils / healing crystals/ other crap like that to anti vaxxers should also be held accountable to some extent. | I know, i know, companies shouldn't be held to the incompetence of parents. However, knowing that kids get violently suck and sometimes die for this shit but continuing to sell shit to those assres, should be a crime. Those companies are complicit in this.
Reason 1: they are legit costing lives. If companies told anti vaxxers their crap don't work, it may not shatter hwir beliefs on the spot, but their hand would get forced.
Reason 2: just plain accountability. People died cuz of the opioid crisis in america, and IIRC, they were sued. I mean, they knew they would become addicted, but continued to sell the drugs. Hold these companies to that standard.
It's pretty obvious but this comes from emotion more han fact, but i still think it has ground to stand on. | If sellers are making claims that oils or crystals can cure cancer or prevent disease, sure those folks should be held accountable. Making false health claims is highly unethical.
However certain oils have limited medical applications. For example, studies have shows that lavender oil can help with insomnia as well as some limited healing benefits for mild cuts.
In addition, many people use essential oils and crystals as part of their religious practice. So I’m terms of religious freedom those folks ought to be allowed to incorporate those items. | 14 | 100 |
Eli5: How is electricity generated? Is there any difference between solar and coal? | Electricity can be generated in many ways, but in all cases it is about creating a difference in voltage. Just like gravity causes things with mass to move from high places to low places, the "electric field" causes things with electric charge to move between different voltages. (And "moving charge" is electricity.)
The most common way to generate electricity is by somehow moving a magnet, which creates a voltage difference nearby. A typical electric generator is basically a series of spinning magnets surrounded by wires - an electric motor working backwards. Coal, natural gas, oil, and even nuclear power plants are just big steam engines for spinning magnets, just using different heat sources to create the steam. Some forms of solar power are the same as well, just using focused light as their heat source. Wind mills and dams are also spinning generators, but they use the direct force of the wind and water rather than steam engines.
Solar panels are *not* the same - they use an entirely different principle. The ELI5 version is that the light knocks electrons loose from the panel, which is arranged so that they can only "fall" back in one direction, causing a net flow. In the same way that a generator is a motor working backwards, these are basically LED lights working backwards. | 63 | 20 |
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[Dragon Ball Z] So I get that Popo is the strongest life form. What is he? What's his story? | Taken from kanzenshuu.com, which derives its material from official guides and from an in-depth research of the source material:
"One method by which the gods of the afterlife govern the Living World is by dispatching personnel to each planet. This is in order to oversee and protect a planet’s sentient life-forms. But beyond this, the main goal is to stimulate an immature sentient species’ growth, guiding it towards the greatest happiness. However, these personnel dispatched to each planet often do not become that planet’s god, but instead serve as a sort of attendant for the god. Instead, an appropriate person from among the planet’s sentient life-forms is selected to serve as god. The principle seems to be that a species’ fate should be entrusted to the species itself, and so the dispatched personnel are only permitted to act in a purely subsidiary role. In fact, Mister Popo and Karin were dispatched from the afterlife to Earth and devote themselves to supporting whoever is selected as god.
— “Dragon Ball Daizenshuu 7: Dragon Ball Large Encyclopedia” (p. 37)" | 18 | 40 |
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ELI5 : p-value in statistics | A p-value is related to the null and alternative hypothesis. Those sound weird but they're a little different than a hypothesis you might have seen in science class.
A null hypothesis says that there is nothing special about the relationship between two things. (Ex: Eating sugar does not increase obesity)
The alternative hypothesis says that there is something special about the relationship. (Ex: Eating sugar does increase obesity)
Now, we have to collect a lot of data from a bunch of people eating different amounts of sugar and seeing if they gain weight. But data is rarely clear. So they use what's called a t-test to see if there is a legit difference between the group of people that ate sugar and the group of people that didn't. The t-test spits out a number. This number, between 0 and 1, is compared to the p-value, a threshold. If the p-value is greater than 0.05, you reject the alternative hypothesis. So if we did this experiment and found that our p value was .06, we could say that random error or chance could cause variation of some people being obese and some not. Now we *could* set the p-value at 0.3 or 0.8, but it's kind of defaulted at 0.5.
This doesn't mean that the experiment failed or that the other side is "wrong", it just means that in a world where sugar does not lead to obesity and the two sets of people were the same, here's how likely you are to see the same results you got. So when that number is really small (p-value less than 0.5), it's really not expected. (Note: this doesn't mean impossible, just improbable) | 14 | 17 |
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Why is Silicon Valley located in the United States instead of, say, Europe or Japan? Also, why have other countries been unable to replicate their own silicon valley on par with the United States? | It's a combination of all the elements being centrally located and a bit of luck with being first. For starters you have two strong research universities (University of California Berkeley and Stanford University) that had a tremendous amount of government tech funding during and after World War II. Many of the brightest students moved into the area for those research opportunities. You have a near perfect climate that no one wants to leave (never gets cold, never gets too hot) making it a great place to live and work.
The tech firms that came out of those research grants like Hewlett Packard hired those bright tech graduates. Stanford and Cal gained a reputation as excellent computer science and technology schools attracting the best students and funding the best graduate research projects and again no one wants to leave because of the awesome climate.
Funding floods the area because great ideas are coming out of there. This huge companies grow and then it becomes the central location that top talent is attracted too. Sandhill road becomes synonymous with private equity funding and we come to today where tech talent is cultivated and even bad ideas get funded because everyone wants a piece of it.
There is a vast amount of tech talent in Japan and Europe but those economies were devastated after WWII and it took years to rebuild the infrastructure. Japan and now China have grown there own talent but there is a language barrier with the rest of the world. (English is taught as a second language throughout the world and much of the top tech talent already speaks it. The same cannot quite be said for Japanese and Chinese although there are certainly growing exceptions to this).
Tldr: Great weather, money, great education system, language that top talent learns, money and got there first. | 27 | 22 |
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If a p value of p=.01 was obtained does that mean that the likelihood of my results being due to sampling error would be 1% or 99%? | I am finding it hard to get my head around so if someone could explain to me I would be very greatful! | The p value is the probability of observing the result you did given the assumption of the null hypothesis. If you get an extreme p value, the implication is that the original assumption is false. However, there may be many reasons your p value is extreme - unrepresentative sample, poor randomisation, other variables (measured or not), incorrect assumptions about the distribution, incorrect use or interpretation of tests. As someone else said ITT, the assumption is that you did everything right up to that point, the p value can't root out bad study design. If you suspect a sampling error has been made, then strictly speaking you should try to quantify the error and the effect it has had on the results, redesign the study, recalculate your required sample size and go again. | 164 | 515 |
Eli5: why are eyes only blue, green or brown (With varying shades), and not colours like red, purple, orange, etc? | Eye color=what kind of colored stuff is in the eye+how the eye scatters light. The first part is easy. The human body makes melanin, the same pigment that determines skin color, and the iris of your eye has more or less of it. Lots of melanin=brown or black eyes, end of story. There are other pigments that can contribute to amber or dark green eyes.
The other part is weirder. It comes down to how light is scattered by fibers in the iris. This is the same kind of physics that explains why the sky is blue, why skim milk looks kinda blue, or why some bird feathers are colorful even though they don't have any coloring in them. If there's not much melanin or other pigment, then this explains more of the lighter colors like blue and green.
At the end of the day, all color questions boil down to "that's what it does with light." | 384 | 526 |
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[Harry Potter] Why does money even matter in the Harry Potter universe? | They have magic. It's already been established that you can produce water straight from the wand. You can transfigure something into something else. Oh no, the couch broke? Better transfigure this thumbtack into a brand new couch! The Weasley household was always described as cramped, but in the fourth book Mr. Weasley is able to use magic to make a small tent into essentially a huge tent-castle. So why does money matter if they can just do anything with magic? | The same reason money exists everywhere else, to procure goods or services from other sources that one might be unable or unwilling to procure by their own means.
Not everyone is good at everything, some people specialize in areas and it's worth it to have them do it instead of you. For example: Bob is good at potions, and Sally isn't. Sally needs Potion X - she could try brew it herself which might take a long time and/or result in disastrous consequence, *or*, she could pay Bob to do it.
Some things you are *able* to do, but don't *want* to do if you don't have to: Jessica is an able potionist, but is also an avid researcher of dragons. She needs a flask of Potion Q; however, it takes several months of careful attention to brew the quantity she needs. Jessica *can* create the potion but doesn't *want* to take the time to do it. She'd rather be out in the field studying how what phase of the moon an egg hatched under affects temperament in juvenile Hungarian Horntails (or something like that), so she pays Bob to brew it for her so that she can go do other stuff.
The tent's an example of this: Mr. Weasley didn't enchant the tent himself. Someone good at enchanting somewhere else at some other time enchanted the tent, which was bought by Mr. Weasley's coworker, which was lent to Mr. Weasley. | 58 | 50 |
What would happen if every mosquito on earth dropped dead right now? | This includes every mosquito egg, larva, etc from every mosquito species. | Depends on the region you are considering. In the arctic, which has very low species richness, you would have removed one of the key links in the very short food chain. Migratory song birds which feed of the adults would go hungry and probably fail to breed. Char and lake trout who feed off the larvae and nymphs would loose their main food source. These effects would then work up and down the food chain.
INB4 "blackflies will take up that niche": Blackfly larvae could not substitute for mosquito as they live in biofilms on rocks in springs with strong current. Mosquito larvae colonize small stagnant pools and lakes and ponds with low currents. very different conditions. | 38 | 103 |
ELI5, Why is Molten Salt(?) Used for heat transfers? | 1. Relatively large heat capacity: on the order of 1 J/gK
2. Relatively dense: on the order of 2 g/cc
3. Very good working range: depending on your choice you get a few hundred degrees of working temperature between "melts" and "boils/otherwise breaks"
4. Relatively cheap
5. It turns out that a LOT of compounds are technically salt
When you're designing a heat transfer system, you want something that can carry a lot of heat per unit volume, that is relatively cheap, and that works over the range of temperatures you need. Liquids work well (in comparison to gases, which don't usually hold as much heat in a given volume), and if you're looking for a liquid that works at 500C -- pretty much all the results you'll find will be different salts. | 155 | 433 |
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ELI5: Where did all the soil come from? | When the Earth was being formed it was essentially a ball of rock. How did soil come to be if there was nothing but lava and rock?
Or am I just missing something here?
Edit: Wow guys, thanks for the replies. | TL;WR :: Erosion, Dissolution, and Poop
1. Gross mechanical processes turn large chunks into small chunks.
2. Chemical processes dissolve things, particularly water and such.
3. Biology is chock full of gross mechanical and chemical processes.
So there's a difference between "dirt" and "soil".
Dirt (and silt, and clay, and sand) is the mechanical, un-living accumulation of fine particles of minerals and metals and ash and whatever.
Soil is what happens when dirt is full of living material and organic byproducts (recently living but now shredded or dead stuff).
So dirt is formed by grinding up and dissolving rocks and such.
When a little dirt shows up somewhere then hardy organisms tend to show up just a little later - or in the case of lichen and moss, sometimes really super hardy organisms show up first.
Windblown dirt-and-dust collects in the crevices and then organisms (bacteria, fungus, algae, whatever) take shelter in the dirt-and-dust and use the mineral wealth of the dirt to thrive. As they grow and die there's now more mineral wealth along with some fixed carbon and nitrogen in the little microscopic corpses and poop stuck to the dust and dirt, and larger organisms can show up.
With more sticky and more crevices comes more dirt and dust, with more dirt and dust comes more places to get sticky and so on.
So if you grab a selection of moss you'll find that dirt is collecting between the fibers and becoming soil.
If you look at a decaying woodpile, you'll find the same thing.
So all these small cycles add up over thousands of square miles of dirt and dust, over millions of years.
Eventually you've got herds of bison and cows and deer and raccoons and prairie dogs and spiders and bugs and whatever constantly living and pooping and dying. Turning more and more dirt into thicker and better soil that's full of more and more diverse things like bacteria and fungus and bugs and worms and microscopic plants and animals and so on.
We'd be neck-deep in soil... but soil has enemies too.
Soil can get washed away, which at natural levels is good for the water right there and down-stream. Soil can be crushed until it suffocates and becomes packed dirt again. Soil can be buried under dirt or ash and so sufficate. Soil can be dried out until it's just dust.
Soil can also be killed by too much acid or too much alkali or to much salt (salt being what you get when you mix acid and alkali).
And some biological systems "don't like" soil.
For instance "rainforests" tend to have very little soil. The rainforests are deeply invested in the nitrogen and nitric acid cycles. So all their biological value is in the living plants. The ground beneath the plants is very acidic and so there's lots of dirt but only a tiny layer of soil. This is a _necessary_ configuration, but when someone decides to burn down some rainforest to create a cow pasture or farm, they'll use up the tiny, crappy layer of soil in just a year or two.
It's easy for something disruptive, like a farm, to "use up" the soil and then there's nothing left but dirt. Especially if the local soil is the result of buffalo and grass and wolves and prairie dogs, but the farmer drives off all of that and just plants corn or wheat. The soil was used to a diet of all that other stuff and now it starves... like trying to make your dog a vegan, it's just not the right food for the organism at hand.
| 77 | 92 |
ELI5: I read today that the SpaceX space suit was tested to double vacuum pressure. If a vacuum is zero, then how can it be doubled? | A single vacuum pressure is when you have a vacuums worth of pressure on one side and an atmospheres worth of pressure on the other.
If they double this, this means they had double atmospheric pressure on one side and a vacuum on the other. | 43 | 20 |
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The right to not die... | This crossed my mind a little while ago and I wanted to explore it further...
It's a little bit tricky for me to get what I want to say across but I shall try my best! Haha.
Sure human beings will perish at one point or other - everyone knows this 100% But as far as our human rights are concerned, technically speaking would to not die PERIOD be one of those rights? Yes, I am talking about immortality.
As I understand it our human rights are designed to protect us from most kinds of danger and to give us freedom. But when we talk about death - it can be argued that dying is actually a harmful thing (quite so!)
It may seem silly to ask this type of question - but there are many sorts of things out there that we have a right to be safe from.
And when we venture into the realms of bioethics - dying is something that is **absolutely forbidden** and is avoided at all costs.
So to conclude once again - do human beings have a right to be immortal? | I think your question highlights an important weakness in 'rights' discourse. Where do rights come from, and what is their basis? We like to treat them as though they just exist, eternally out there in the world, but clearly that isn't the case.
For example, there is a push to make access to the internet a human right. Did that right exist in 1920, and we were just all having it violated because the internet didn't exist yet? That doesn't seem reasonable.
If anything, that right came into existence when it became socially reasonable to provide internet to most or all people. So it's not that we had a pre-existing right to access the internet, it is that it became socially just to ensure equal access when that became economically feasible.
And if that's how rights work, we can't have a right to immortality. If it's technologically impossible (as it currently is) then it's like having the right to the internet in the 1920s.
But then 'rights' discourse seems to treat these contingent, socially embedded facts (like there is enough internet to go around) as though they were objective, natural facts about what people ought to have. If that's the case, why not just talk about just distribution of resources, rather than 'rights'? | 17 | 15 |
What traits are considered "masculine" vs "feminine" (among humans) and how much does this change from culture to culture? | Females are associated more with jobs that allow them to be in one (or very few) places throughout the course of the day. Not surprisingly, this has to do with child rearing. What they lack in mobility, however, they make up for typically in the variety of tasks that are assigned to them.
On the flip side, men tend to venture further away from the home base. This is seen in activities such as hunting, fishing (from boats) and even in the wage labor system (which is now becoming more blurred as a gender specific activity due to increasing industrialization). These activities that are "masculine" are also those that individuals tend to focus, or specialize in, because this situation opens up the potential for a more single minded focus than the situation of the typical female role does.
Gender roles do vary between cultures, but the basic idea of women being more constrained to the household because of child raising, while men (unconstrained) take on the jobs that require more travel. A good example of this would be Pacific islander men fishing for weeks at a time on the ocean from vessels, while the women of these cultures fish from shore as a sort of dietary supplement.
Some traditional farm based chores will vary from place to place as well. For example, who tends after small animals verses large animals, or who is associated with the different stages of the agricultural process.
edit: very to vary. | 36 | 64 |
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