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5okucc | Why hasn't Africa been able to emulate the economic success of Asia? | Why have there been so many countries in Asia like China, Japan, Singapore and South Korea that have been able to develop so much in the past decades yet the countries that make up Africa haven't been able to do so? | Economics | explainlikeimfive | {
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"This question has hundreds of answers and entire PhD programs and world agencies dedicated to answering it. So... it's not easy to ELI5. Much of Africa has poor soil which makes growing things for profit difficult. Couple that with hundreds of years of colonization that extracted resources (and people) and you are left with a landmass that has very little natural resources controlled by the people who live there. Because most (all?) of Africa has been under someone else's rule at some point in history the institutions that foster growth didn't exist until recently (like the last 50/60 years). There was no centralized education system, private market that grew economies, and stable political system to guide all of these things. Basically successful societies have 3 things: stable government that caters to the majority and not a small ruling family, robust public education, and some sort of natural resources. in the case of singpore (who doesn't have robust natural resources) they have a very highly educated population that makes up for lack of resources with technology.",
"A lot of it comes down to benevolent leadership, and in some ways Africa's natural resources have been a curse rather than a blessing. It's far easier to let outside companies come in and harvest your oil, diamonds, etc. in return for royalties on those raw resources than to develop your people as a resource. Far too many African leaders have taken that route. However, places like Singapore, Taiwan, etc. didn't have the natural resources to exploit, they just had people. And their leadership were smart enough and benevolent enough to want to improve their countries. They set up schools, they insisted that companies coming in to use their (then cheap) labor train the people with skills, as the populations became more educated and skilled, they were able to move up the ladder from cheap, basic assembly to more technical /skilled manufacturing, and more of their population could take on roles in operations, management, engineering, etc. This virtuous cycle continued, and the countries advanced rapidly. EDIT: While it's been a while, economic development was the concentration of my college degree majoring in International Studies while minoring in Economics. Did a number of research papers on topics along these lines.",
"There's lots of reasons but I'll just take a stab at what I see as the most salient ones: (1) Lack of domesticated plants and animals means Africa has never been as successful in producing food surpluses as Europe and Asia, which put them far behind the power curve as civilizations go. (2) Huge chunks of Africa are landlocked. This means that they had less opportunity for trade and less opportunity for sharing knowledge. (3) Owing to factors 1 and 2, Africa rarely developed powerful empires with centralized government. That's not to say it never happened, but certainly not to the same extent as we saw in Europe and Asia. The people in Africa are divided into literally thousands of disorganized tribes and ethnic groups accustomed to warring against each other. On the other hand, SE Asian countries are highly homogeneous, group-centric, and accustomed to top-down leadership. If an Asian government leader decreed the need for social or economic reform, he could push it from the top down. There is no such tradition of centralized government in Africa. (4) Africa's leaders have, for many reasons, been a collection of kleptocrats. Coups are a routine occurrence. Education is low, poverty is high, and there are few opportunities for reform to take place."
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5okx52 | Why does mental illness get a "bad wrap" within the united states? | Other | explainlikeimfive | {
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"I think it comes with expectations in the US. As someone who was born outside of the US but came to high school and college here, I can definitely say that society places a lot of importance on \"self-determinance,\" or this whole idea that you, and only you, can define your own outcomes. In short, society here tends to have a very \"you help yourself\" attitude when it comes to personal problems. Sadly, in this category of personal problems, mental issues are often placed in there. Many people have this outlook of people not \"being mentally strong enough to overcome mental issues;\" not to make this political, but this ideology was displayed with the remarks of Trump when it came to veterans and PTSD when he said that \"some of them were not strong enough.\" You will hear that rhetoric of strength and fortitude a lot when you are in the US but it acts against those with mental issues two fold by making those who wish to speak out seem weak (derogatory here in the states for the most part) while also making those who are not suffering seem very superior to those who are so it creates this viewpoint of inferiority with these people who often need help."
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5ola9q | Why do electrons surround a nucleus instead of falling into it through coulombic forces? | I know electrons don't orbit a nucleus and its better to think of them as a cloud. The cloud just showing probability in space and their location based on energy orbitals and stuff but why doesn't the cloud just collapse towards the positive protons if it is negative? I haven't been able to find a good answer with google or past ELI5 questions. I appreciate any replies to help me understand! | Physics | explainlikeimfive | {
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"There are a couple of different ways to think about this. First there are the orbitals themselves. When one solves the Schrodinger equation for the coulomb potential a set of discrete energy levels comes out. The precise values depend on the magnitude of the charges, nuclear mass, and electron mass, as well as some constants of nature. These are the allowed energy levels or states for an electron bound to the nucleus (which makes an atom). If an electron is part of the atom, it \"lives\" in one of these states. Each state has an associated location probability in the space around the nucleus, with higher energies generally having a larger probability further away. Another way to think about this in a semi-qualitative way is through the uncertainty principle. Since the quantities position and momentum are linked via the uncertainty principle (which comes from the fact that they are non-commuting operators, or equivalently, the notion that they are Fourier transforms of one another), the uncertainty in position multiplied by the uncertainty in momentum has a lower bound. If you were to confine the electron to the nucleus via the Coulomb interaction, its position uncertainty would be extremely small (10^-15 m or so), so it would have a very large momentum uncertainty. This means in a very short amount of time the electron will have moved a (proportionally) large distance. It turns out that a \"box\" about 0.1 nm (10^-10 m or 1 angstrom) across provides the right amount of space for an electron to have a small enough momentum uncertainty that it stays near the nucleus. This 0.1 nm is about the size of a hydrogen atom. One could make a Pauli exclusion principle argument, but it would only be valid for multielectron atoms."
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5olecp | If a ninth planet exists and easily fits our readings and models, why haven't we found it yet? | Other | explainlikeimfive | {
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"How do we notice most of the planets in our solar system? We observe them because light hits them and bounces back for us to see. The further away they are the harder they are to see, you get to Saturn and you can't see anything with the naked eye. Further out you need binoculars or a telescope to see them. In fact Neptune was only discovered because we noticed Uranus wobbled a bit when it shouldn't. This wobble in fact lead us to think that there was a planet between Mercury and the Sun as Mercury also wobbled a bit funny. As it turned out there is no planet and this movement was explained by general relativity. Pluto isn't visible from Earth at all. Interesting fact, Pluto is so far away from the Sun that it hasn't completed a full orbit since its discovery in 1930. Now look at this proposed planet, it's orbit is MASSIVE compared to Neptune's. It's going to spend most of its time in darkness and without many objects for us to observe nearby we can't easily infer its presence.",
"Planet X as predicted by the models is about as noticeable as a black cat, in a dark room, full of coal, at midnight. We rely entirely on reflected sunlight to *definitely* detect/\"discover\" planets, and there is *very* little of that at a distance where Planet X is expected to be found - it's dark and it's cold. Therefore, it's a ninja."
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5olg1m | How do erasers work? | Technology | explainlikeimfive | {
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"Have you ever rubbed your hands together and felt the warmth? That's called friction. When you erase a pencil mark, you are rubbing the rubber eraser against the paper. The friction between the rubber eraser and the paper loosens the graphite particles from the paper. The sticky rubber in the eraser grabs and holds on to the graphite particles (That's why erasers look dirty after you use them) Since the eraser is soft it doesn't rip the paper."
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5olgys | The commute of Chelsea Manning. | I'm still slightly confused about what this means and how it is done. *Edit: Thank you everyone! | Other | explainlikeimfive | {
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"The President has virtually unlimited power to pardon people who have been found guilty of federal crimes. This power comes directly from the Constitution: > The President...shall have Power to grant Reprieves and Pardons for Offences against the United States, except in Cases of Impeachment."
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5olkrd | How come ancient Greeks, as depicted by their sculptures, were so heavily muscled despite not having optimal knowledge about nutrition and training by today's standards? | Biology | explainlikeimfive | {
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"Would you sculpt yourself as bald, pudgy, with a small dick even if it were these case? Or do you come out looking super Schwarzenegger? Artistic license.",
"A vast majority of peasants would be stuck in physically demanding jobs and low-calorie diets. Only the richest members of society had the resources to live comfortably enough to gain a significant amount of weight. If we spent 12+ hours per day shoveling stables, laying brick, harvesting crops, or going to war, we would all be pretty fit, too. Combine that with a diet that's far lower in fats and sugars and a healthier body emerges. Edit: forgot a word",
"Pretty simple since half the population had gods as parents, and since gods are perfect they gave some of that to their children, thus you got guys like Hercules.",
"Greeks were idealistic in their sculptures. As opposed to Romans who were more realistic in their sculptures. (In general)",
"I guess the majority of people were in pretty decent shape because they didn't have leisurely work. You had to be rich to get fat . Cold in the winter? Go chop a shit ton of wood. Hungry? Walk several miles and but it or work your was off doing manual labour to get lunch. Imagine a world where everything is done manually including transportation."
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5olnu7 | How does a sound stimulate the brain? | Recently, I have started to listen to brown noise while studying to boost my productivity. While listening to it, I could focus and concentrate on studying without being distracted. Being the person easily distracted, this surprised me a lot, so I was just wondering, what is the science behind this? URL_0 Here is the LPT! | Biology | explainlikeimfive | {
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"Brown noise helps you focus by removing auditory distractions. Its the same idea as closing your eyes to help you hear or smell better. Brown noise works better than simply blocking out sound with earplugs because our hearing become more sensitive when it's quiet. In a completely silent room where you can \"hear a pin drop\", the faintest of sounds (e.g. the aforementioned pin) will stick out. Your brain needs to assess all of these faint sounds to ensure they aren't important (a threat, your name being called, etc.). If you are listening to brown noise, you can't hear anything other than the brown noise, so there are no other sounds for your brain to assess. Furthermore, your brain determined the brown noise was unimportant and could be ignored within a few seconds of turning it on, so with no new sounds to interpret, you've done the auditory equivalent of closing your eyes. If you're looking for a bit more science, we can talk about brain regions. Although there are specialized areas for different types of sensory processing (occipital lobe for visual stimuli, the primary auditory cortex in the temporal lobe for auditory stimuli), this information still travels to the frontal cortex to be consciously assessed. Brown noise allows the primary auditory cortex to stop bugging your frontal cortex with dumb messages like \"HEY! A DOOR JUST OPENED! DO WE CARE?\" and lets it focus on important things, like the exam I should be studying for right now. **TL;DR listening to brown noise is the auditory equivalent of closing your eyes to focus**",
"\"Your brain is especially attuned to detect changes in your surroundings. If there's a low level of background information...when it's silent almost any sound can alert your brain and you can't help but to pay attention...like a dripping tap or a snoring partner...white, pink and BROWN noise playing across all frequencies are like a muffling blanket of sound....they mask other sounds by making them less significant when compared to the background\" ...I didn't explain it like you are five, [its from this SciShow] ( URL_0 ) Essentially brown noise isn't distracting, its a nice blend of sounds balanced for the human ear so that the highs aren't too high. This helps minimize outside interference allowing you more brain power to focus on the task at hand rather than wasting it interpreting random noises, a trait which may at some point in human evolution permitted you to survive and extended your gene pool's fitness but now, in the age of information, prevents you from studying. EDIT: I attempted to provide my own summary of the video",
"Brown noise or white noise helps you focus because the brain processes it as silence. In a quiet room and even in complete silence, slight noises like the beating of your heart or blood flow through your ear are still present. Brown noise covers these sounds up and replaces it with a more complete\"silence.\"",
"I've always heard it called \"white noise\". Is there a difference? Never moind. URL_0",
"What you are looking for is most likely the phenomenon of [stochastic resonance]( URL_0 ). Simply explained, it works like this: To successfully send and receive a signal, your nerves/neurons need to get their electrical signal over a certain threshold so that it counts. If you add random but constant noise to the situation, it adds to the strengths of all signals, making them more likely to cross the threshold and being effective. The German wiki-article has a good picture too explain it: URL_1 So now more of the signals have effect, which is similar to having better concentration/\"stronger brain signals\". The isolation from distractions is also very useful, but complete silence without distractions would have less of an effect than white noise. A related example would be one of the main factors of ADHD: Due to a lower dopamine level, control-signals in the frontal lobe are less likely to have an effect and an ADHD brain needs more effort to reach the same level of concentration/control. If you correct the dopamine level through certain drugs (which would put other people in TOO-MUCH-DOPAMINE-EVERYTHING-IS-INTERESTING-MODE aka \"being stimmed\"), concentration returns to normal level."
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5olp8r | What happens when you recycle something that isn't recyclable? | Biology | explainlikeimfive | {
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"Dang it, I read an article about this just recently and now I can't find it. There are people whose job is to watch the stuff come down a conveyer belt, and they pick out what is not recyclable. They can miss things, though, which then go into the recycling, uh, machines (I should really find the article) and can mess the machines up pretty badly. After I read this I started being a lot more careful about only putting what is actually recyclable into my bin."
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5oltof | Why do smoothies and drinks at juice bars cost so much? | A regular sized fruit smoothie at Booster Juice is around $6 to $7 and I see the staff using blenders to make the drinks. They also sell mini wheatgrass shots for $3 and energy boosters. What is the reason the drinks cost more versus using a blender at home? | Economics | explainlikeimfive | {
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"You're paying for the cost of renting the location and paying the staff to make you it. It's the same with restaurants charging 2-3 times the price for food and drinks."
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5om3yf | How can fish be frozen, then be fully animated after thawing? Could this mechanism work with other large organisms? | URL_0 (The post I'm referencing) | Biology | explainlikeimfive | {
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"I'm going to copy a post I just wrote for [this]( URL_1 ) thread. Cryogenic freezing of large animals and humans creates several issues: Problem #1: Saying goes freeze slow, thaw fast. A freezing rate of -1 degree per minute is ideal for most applications. The slow freezing prevents cell rupture by allowing excess pressure caused by water expansion to leave the cell. Water crystals are also smaller when water freezes slowly and thereby do not create quite as much damage to the cells. Human body is 37C so this would be over half an hour just to get to the freezing point. At room temperature, highly metabolically active organs, like the heart and brain, show significant damage after 4 minutes of being without oxygen. What use is being cryogenically frozen, if you're brain dead? Problem #2: When freezing cells, we usually add DMSO and/or glycerol. These are cryopreservative agents that will prevent ice crystal formation and permeablize the cell membrane so cells do not burst from the water expansion. Cryopreservatives also tend to be quite toxic and must be quickly removed after thawing. It would be difficult to flush these out of a human so liver and kidney damage would likely occur. Problem #3: When \"waking\" cells from cryostorage, they will suddenly become metabolically active and very quickly use up any nutrients available to them. Therefore it is important to immediately supplement the cells with media containing sugar and amino acids, as well as add FBS (fetal bovine serum) which contains many trace nutrients and growth factors. It's hard to administer enough nutrients to a whole person. Problem #4: Even with a perfect freezing procedure, there will be some cells that rupture and die. While individual organs can recover from some widespread damage, your immune system recognizes when there are parts of a cell's insides on it's outsides. Immune cells activated by the exposed cytoplasmic proteins would release cytokines (immune chemicals) that would cause widespread inflammation. This would cause septic shock leading to death, the same mechanism by which a severe bacterial infection leads to death. About fish and frogs: Most lakes do not freeze completely in the winter and the ice will only occupy the first couple feet. This allows fish and frogs to remain near the bottom and simply slow their metabolism the same way a bear would hibernate through the winter. With a greatly reduced metabolism, they can live off of body fat and do not need much oxygen. Frogs that do freeze and thaw with their environment have evolved an elegant solution; they use an \"antifreeze-like\" blood mechanism, where nucleating proteins cause their blood to freeze more quickly than the rest of the animal. This slows the freezing rate of the rest of the body, allowing the liver to pack glucose into the cells. This glucose acts as a sort of scaffold and provides an immediate energy source to be utilized upon thawing. Nat geo wrote an interesting article [here]( URL_0 ) that talks about it, I got to learn something too! This method would help but our liver would struggle to produce adequate amounts of glucose, our brains are far larger (much easier to damage) and cold blooded animals have vastly different immune systems then us, allowing them to escape the immune mediated septic shock we would experience. Not saying it can't be done, but current technology would make it extremely difficult and risky. Source: I do immunological cancer research and freeze/thaw human cell lines all the time. Edit: About the video link - I am going to assume the fish was only in the freezer for a short amount of time and has gone into a reduced metabolic rate called \"topor\", much like a shorter version of the hibernation seen in lake fish during winter. If the fish was fully frozen, I would've expected it to take much longer to defrost (think about cooking frozen salmon in the oven). No information was given about the length of time spent in the freezer and it is much easier to recover from hibernation-like state than from a fully frozen state.",
"Fish have a less advanced anatomy, having many unique yet basic features, which will probably be the reason for this occurrence. Regarding the second statement, well, we have succeeded in reviving tiny parts of large animals, but for now, no, we can't. This is because mammals are innately warm-blooded, and being frozen creates ice crystals which impact life mechanisms. Thawing can cause serious damage and they'd probably die anyways. I recommend you research cryonics, they have a bunch of things about trying to preserve humans via freezing and they elaborate a bit more on this, and ways they prevent ice crystals.",
"Freezing is generally bad for a few reasons, it stops the flow of blood, it alters the rate of reactions within cells, but most importantly, ice crystals are sharp, and they tend to burst cells when they turn the mostly water in them to mostly ice. Some plants and animals can resist this effect using antifreeze proteins. These can operate in a few different ways. Some animals avoid the actual freezing by lowering their internal freezing point by a few critical degrees, since most water is warmer then the freezing point, they just need enough to get back into warmer temperatures when they notice it is too cold. The more interesting freeze-tolerant creatures have specialized antifreeze glycoproteins which can bind to the ice crystals themselves, preventing the crystals from growing large enough to burst their cells. Once the creature thaws, all the cells are in good repair and it can simply move on with its life."
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5omdo1 | why is "night vision" green? | Technology | explainlikeimfive | {
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"Back in the day, night vision goggles relied on vacuum tubes, specifically, photomultipliers, that were much more sensitive to light than human eyes. These tubes basically, as the name suggests, \"multiply\" light, making it easier for us to see. Now, the displays worked like old-school computer screens, or \"tube\" monitors, where an electron beam would light up a \"phosphor\" coating on the screen, making a bit of light that we can see. It just so happens that our eyes are more sensitive to green, and if I recall correctly, green phosphor was easier to produce in a stable form. Basically, we can see green easier, and they kinda worked like old tube monitors.",
"As I understand it, the human eye can distinguish between and see more shades of green than any other color, so having NVGs display in green allows us to \"see\" better. Also why some lights with a map reading mode are green A lot of illumination sources for being all sneaky have red tints because illuminating things in red preserves our low light vision better than any other color.",
"The human eye is the most sensitive in the green part of the spectrum. Because of this, people can identify more shades of green. Night vision technology doesn't pick up color too well, so instead of color you get a grayscale. Gray (or any other color) isn't as easy to see as green, so it's just like black and white only instead it's a greenscale.",
"During the day, the cones in our eyes are their most active and pick up on red light much more effectively than they do green light. During the night, we cross over into our night vision by undergoing a process called dark adaptation. Our rods in our eyes become more active than our cones because their primary function is to pick up on the absence or presence of light (i.e. light or dark). The rods have basically no job during the day other than say the obvious, \"There is light everywhere!\" But, at night, the rods have a much more interesting job to do. The eye's focus on using its rods also makes the cones perceive green as brighter than red since the cones shift their focus and now have the easier job. This is a perceptual reason why night vision goggles and displays use green light. It is also the reason why the vast majority of alarm clocks use red light to avoid disrupting sleep as much as possible."
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5omxkl | Why shouldn't we drink water from airplane bathrooms? | Other | explainlikeimfive | {
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"[Simply not potable.]( URL_0 ) Now, let's talk about the coffee."
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5on670 | How did America manage to amass so much power so quickly? | Other | explainlikeimfive | {
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"This change happened during World War II, when all the other great powers devastated each other, leaving the USA (due to its geographic isolation) largely unbombed and uninvaded, with all its mighty industries intact. That, combined with vast natural resources and a very strong educational system, and a culture that welcomes innovation from all directions, did it.",
"For the most part it is due to both World Wars. WWI brought the US up into the ranks of being a World Power, but Britain was still the Superpower. WWII however destroyed so much of Europe's infrastructure that it killed the remnants of the great Empires. America was able to operate on the global stage with very little competition, had virtually no damage to its infrastructure, and had numerous customers in the reconstruction of Europe and Japan. This period of virtually unchallenged economic growth was enough to push it to Superpower status. Now the USSR was a rival because despite taking a lot of damage during WWII took less than the rest of Europe and it had massive resources it could extract from its eastern regions. So for a while it was able to compete with the US somewhat, but because it did take damage most efforts were spent on self repair rather than aiding other nations, at least for the biggest part of the boom which was during the 1950s. After that it did start to support other communist nations and we get the Cold War with Two fairly equal Superpowers. Then the USSR collapsed and left the US so far ahead that no other nation was able to step up in competition. During this time China went from a regional power to a world power, and is rapidly gaining influence and will \"soon\" be a Superpower. But China is not there yet economically or militarily. Russia is also fighting hard to regain Superpower status, but is far from being back in the top spot despite its recent posturing.",
"Very few countries/groups of people had a steady rise from less powerful to more powerful. Most rose and fell. You don't think of Italy or Mongolia as world powers, but they once were. The US had a privledged birth. It got to inherit the technological advances of Eurasia and apply them to a continent that had fairly untouched natural resources. It then benefited from only two borders, which while long, have been relatively peaceful. Compare this to European countries that were largely constantly at risk of war for most of history. Geographic and political isolation as others pointed out left us relatively untouched by the world wars (even our fatalities, while tragic, were relatively modest compared to population size and the physical destruction was basically one port on hawaii). So we got the benefits of a huge land mass, huge population, the tech from all of history to start with, fertile soil, lots of great rivers and ports. And the north won the civil war. History is very different in a world with an unUnited united states"
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5on8i2 | Why do people with psychosis go through cycles where sometimes they are OK and then they have a psychotic episode? | I had a friend who seemed OK for months at a time but then would have a psychotic episode where he was delusional and manic. Then he would be OK for a while but cycle back into psychosis. What's going on in the brain that causes that cycle? | Biology | explainlikeimfive | {
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"Bipolar I here. I've been through psychotic mania as well as several cycles of less severe mania/depression. We know in the cases of people with bipolar disorder that there is a chemical imbalance in the brain. Your brain doesn't react emotionally the same way that other peoples' brains do. Often, regular occurrences will \"trigger\" people with this disorder into extreme highs or lows. For example, when I went into psychotic mania, I was doing really well at work, I had just restarted school, my relationship with my boyfriend at the time was going well, and I was on my way to getting my financial life on track. I was also taking an antidepressant at the time, Celexa, that had a black box warning that it could cause mania. I'd never had symptoms of bipolar prior to this. All of the good things in my life combined with the antidepressant just sent my brain into overdrive and I snapped into psychosis. Six weeks later, I got my official diagnosis and started on mood stabilizer treatments. It's been three and a half years that I've been managing my disorder, and I'm now in cognitive behavioral therapy to possibly one day manage my disorder without medication, but it's a long road ahead.",
"While mania is a symptom of bipolar 1, as opposed to hypomania in bipolar 2, psychosis can have many different causes. In the case of a structural anomaly such as a tumor or cyst, it is thought that a \"trigger\" can cause higher or lower activity in that brain region which is then amplified by the improper structure, essentially making it reactive to stimuli. Psychosis due to biochemical reactions such as low dopamine in schizophrenia are similar in that they can be a reaction. A difference in illnesses such as these (schizophrenia or bipolar or other mood disorders) is that the amount of any given neurotransmitter is constantly fluctuating in everybody. So only when these fluctuations coincide with the illness do the symptoms occur. In the case of dopamine caused psychosis (like schizophrenia), when the brain is regulating dopamine more efficiently, symptoms do not present themselves and the individual appears \"normal\". When the the levels of these neurotransmitters get closer to the levels that are problematic or cannot be managed properly, symptoms are exacerbated. Psychosis is obviously not in the individual's control and it is definitely not a matter of \"mind over matter\". The biological basis of psychosis is the cause of the ebb and flow of symptoms."
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5on9qm | How come when you wake up your bed feels entirely more comfortable than when you initially try to go to sleep (or even throughout the night while you're sleeping)? | Other | explainlikeimfive | {
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"As you sleep neurotransmitter levels change. As sleep approaches and starts melotonin is released to induce sleep and cause drowsiness. As morning approaches levels of serotonin increase. This causes feelings of well being and increases pleasure associated with tactile sensation. (Bed feels better)",
"Literally every answer in this thread so far is entirely made up according to whatever the hell sounded reasonable/anecdotal to the commenter. I'm a doc and there's no scientifically proven answer to this question. Edit: Some people seem to take offense to the fact that I stated that I'm a physician as evidence of credibility. No, I'm not going to post my name and medical license to prove it. Yes, it does lend some credibility beyond a random person making up theories, given that I have studied human anatomy and physiology. As for my statement that there is no scientific evidence to back up anybody else's claim on this thread, go ahead and run a pubmed search and see for yourself. I can't provide you evidence showing that there is no evidence.",
"When you go to bed at night, you've been moving around all day and your muscles are still prepped and active for movement, and weaker as you've been using them all day. As you're laying in bed, unless you're utterly exhausted, you have to find a position where your muscles can relax best. Once you fall asleep, you stop moving completely for a few hours on end which causes your muscles to stiffen. When you wake up in the morning, you generally feel amazing as you've begun moving again and stretching. Stretching makes your muscles relax and stiffness of sleep go away, which is why it feels so awesome to lay in bed after waking up and moving a bit. Your muscles are so relaxed after a morning stretch that any position is comfortable. This is also why it's so much easier to fall asleep at night if you do proper stretches throughout the day. It could also be a psychological thing either caused by the warmness of the blanket vs coldness of the morning, or having to do with getting up and going to work",
"There's like four different answers here all saying different things. Which one(s) is the real one? Can I get sources for answers?",
"I don't think anyone truly knows. My guess is that it's because you relax while sleeping and settle into more natural body positions that you can readily fall back into. I also feel like muscles need some time to \"wind down\" and feel comfortable not moving. Just a wild stab, though.",
"Hmmm. I'm guessing you are below the age of 35. I used to be able to lie in bed forever. Now I have to get up in the morning otherwise I get all achey and sore.",
"You don't want to go to sleep because it's one step closer to getting out of bed in the morning. You don't want to wake up because it's one step close to getting out of bed in the morning.",
"I work the night shift,have an 11 month old and we have had dozens of cms of snow in the last couple of weeks. My bed feels AWESOME when I get into it. For anyone reading this go buy yourself a new, high thread count set of sheets. Add a new set when you see them on sale.",
"Probably because you don't want to get up. Putting new sheets on your bed is the most comfortable you will ever be.",
"Easy: Comfy vs responsibilities (going to work/school) Warm and fuzzy vs cold bathroom/shower (Winter) Awesome dream (having sex with a supermodel) vs Face reality, shitty job, shitty husband, etcetera Going to bed (wasting your life away) vs staying up and finding the love of your life, win the lottery, finish watching that awesome infomercial..."
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5onm7q | If I see a face/thing that I am very familiar with (family member etc.) and then "study it", it can suddenly look weird or unfamiliar. What is this and is it common? | Biology | explainlikeimfive | {
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"The reason is because humans have evolved what basically is two systems of thinking. System 1 is the instinctual, intuitive process that all animals have. It is fast, has access to nearly all of your memories, and brings quick information based on heuristic shortcuts. Part of this is is an individual-recognizing system that automatically says \"this is Bob.\" Almost all animals have it, though it is not always based on vision of faces. System 2 is the conscious, intentional thought. This is slower, and you have a limited amount at a time (focus or attention), but it allows you to assess things in a more ordered detailed way. This is thought to be what we call sentience. When you intentionally study a face, you are calling on system 2 and suppressing system 1, so you can view features and not \"Bob.\" This throws off your automatic pattern recognition that is the default. It creates some dissonance in your mind, and the face without the automatic intuition seems strange or alien. This topic interests me a lot because being aware of your conscious vs automatic thought processes can be really useful, because system 1 is usually working with more information, but it has a tendency to jump to conclusions and have a lot of biases. Awareness of when and when not to rely on the things that automatically pop into your head can make your decision making much better.",
"Jamais vu... is the closest I can think of. It's the opposite of Deja vu. Google/wiki it. I don't know how to add a link.",
"You can experience this if you stare at yourself in the mirror long enough and examine your own face. It's really unsettling when it kicks in!"
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5onmkm | When rolling a ball on a flat surface, it produces a rolling noise (eg. Going bowling). What is actually causing this noise? Being a sphere, there isn't really an 'impact' while its rolling for the noise to be produced is there? | Physics | explainlikeimfive | {
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"Actually, a rolling object could be more thought of as having many more impacts, just with less force. A square object \"rolling\" would have four big impacts, while a bowling ball would have tons of tiny ones, which add up to the smooth rolling noise. Source: It makes sense in my head so I hope that's how it is Edit: think of the atoms. As the ball rolls, the object itself stays on the ground, but each surface atom is constantly going up and down, taking turns hitting the ground and then getting rolled back up. That's what makes up all the tiny impacts that cause the sound",
"The [roundest object on Earth]( URL_0 ) , if scaled to the actual size of the Earth, would have 14 to 40 meters of difference between the highest peak and the deepest valley. Bowling balls are reeeally irregular, so they make many tiny jumps every second. The rolling sound is the sound of the ball bouncing towards its target. Edit: grammar and amount of meters",
"I'm no expert, but I'm thinking this is because the flat surface you're talking about isn't actually totally flat, and the ball isn't totally spherical. I'd bet perfectly round object rolled on a perfect flat surface wouldn't make a sound aside from the slight wind noise it would create, which our ears probably couldn't pick up anyway."
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5onodk | What causes secondhand embarrassment? | Other | explainlikeimfive | {
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"Cringe is an empathetic response. We're social creatures and caring for each other is a part of that",
"Pretty much everyone has some level of empathy. We get mad when we see someone else being treated unfairly. We're sad when we see something tragic happen to another. We can't help thinking about how we would respond in that situation. So we feel embarrassed or get \"douche chills\" when someone is making an ass of themselves."
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5onqvq | Why is the cure for the common cold so hard to find? | Biology | explainlikeimfive | {
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"Which one? The common cold is a whole genus of virus, Rhinovirus, and there are lots of them. Beyond that, viruses mutate* pretty fast, and some of those mutations make a formerly effective vaccine basically worthless. Once you get a cold you're immune to that particular virus, you won't get that specific cold again, but you might get sick from one of it's great-great-grandchildren a few months later. Edit: mutate, not mutation"
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5onvaw | if you reverse a reversed video, why does it still look very strange? | Technology | explainlikeimfive | {
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"So you tried to un reverse the backwards running gif? The issue is compression I think. All formats of video have it and it can't be undone completely. So you lose some with the original and you lose some when you reverse it. And you lose some when you reverse it again. It's like putting a phrase both ways through Google translate. Enough is lost that it sounds really weird but still generally the same."
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5onvlh | If deep freezing only puts bacteria to sleep rather than killing them, then why does deep freezing sushi/sashimi fish makes them safe to consume raw? | I've been told that deep freezing food doesn't kill all the bacteria and only puts them to sleep. However, when I look up about sushi/sashimi, they often say that freezing the fish is one of the things they do to kill bacteria. What's the true story here? | Biology | explainlikeimfive | {
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"I think you're confusing bacteria with parasites. Freezing kills harmful parasites like tapeworms and roundworms. The bacteria you're concerned about has nothing to do with the fish itself and everything to do with who handles it. If there is any harmful bacteria on your sushi, I'd blame your chef for not washing their hands.",
"I import fresh seafood for sushi. Freezing is for parasite prevention and is usually assumed will be done in the restaurant or markets care with sushi fish.. Tuna is an exception and does not need to be frozen, i think this is because parasites are rare in tuna. I have had some fish with weird things but none that would get past the first customer who cuts and distributes the fish."
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5onwec | why won't companies like Valve make games such as Half Life 3 which would pretty much guarantee them unimaginable profits? Is there another reason for not doing it apart from the risk of it not being that good? | Technology | explainlikeimfive | {
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"Valve is making money hand over fist with Steam. Half Life 3 has impossible expectations to live up to so I'm sure they'll wait until the risk doesn't outweigh the reward. Why risk messing things up right now when they're doing really well? Square long ago said they would never remake FF7. They're now remaking FF7 because something about their situation changed and they think it's good for business. That might happen in the future to Valve but there is really no way to tell without waiting for it to happen."
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5oo0ee | Why do budget airlines use newer and efficient planes such as the Boeing 787 and Airbus a350 while full-service airlines such as KLM and Lufthansa use older less efficient planes such as Boeing 767 and the Airbus A340 | Economics | explainlikeimfive | {
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"The old model for most legacy airlines was to purchase planes when needed and fly them as long as possible. They are fairly stuck in that business model trying to get as much money out of aging fleets as they can. Newer budget airlines, at least the larger ones with lots of capital, make huge bulk buys. This severely lowers the cost of the planes. Then after a few years they retire those planes and sell them to smaller airlines without the capital to make those types of bulk buys and again buy in bulk. They are able to get a pretty decent return on the relatively young used planes while continuing to buy at a discount. This also keeps their maintenance and running costs low. Another tactic budget airlines use is only buying one type of plane and building routes around that type of plane. On the other hand older airlines buy different types of planes to meet many different types of routes. Again buying the same type of plane allows for bulk buys and lowers training costs of their personnel."
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5oo1c5 | Why (in the US) are medical payments so astronomically high, resulting in many people defecting on the bill? Wouldn't you make more money if things were more affordable so that more people can actually pay? | If you're lower-to-middle class and have an emergency that costs +$100,000, but can't pay because it causes bankruptcy, how is that better than charging ~$5000 that *could actually* be paid off? Isn't it better to make a steady stream of reasonable money than charging absurd amounts that can't be paid? | Economics | explainlikeimfive | {
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"Well first, you might declare bankruptcy but that doesn't mean they don't get any money. They can seize your assets, they can garnish future wages, take you to court and so on. They won't get back 100% of the money (unless they get a good court win), maybe only 30-60% of it, which in turn raises the price on all medical care so that the hole met by bankruptcy patients are covered by insured ones and costs plus profit are met. Second the prices are so high in the US because hospitals mainly bargain prices with insurance companies, and the 'sticker price' is artificially high so that they have better bargaining positions for the prices of bundles of surgeries or days in hospital for multiple patients and so on. The hospital likely sits down with a patient and 'forgives' some of the debt owed when settling on a repayment plan yet still makes money. Thirdly you can't bargain on prices in hospital as a patient. In the ICU ward you'll die if you refuse medical care because you think it's over priced. This is in economic circles called inelastic demand. Medical industry is a price inelastic industry. Where there is a price inelastic industry, in the absence of government intervention, prices are high. Most other price inelastic industries have government intervention (drinking water, food, rent) just not medicine. This is a large part of why medical costs in the US are higher, other countries control prices in various ways. The extra money goes to drug companies, share holders of insurance companies and hospitals, and the top 25% of doctors. Basically those who command bargaining power in the system. and finally prices are so high because medical care is very expensive.",
"Taiwan has one of the best health care system in the world. but it's profit loss. I guess it's simply the American gov didnt want that"
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5oo5xf | When we say we've "mapped the human genome", what exactly does this mean? | Biology | explainlikeimfive | {
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"DNA is a lot like a cookbook that your body uses to brew proteins. Proteins are themselves made from amino acids that are glued together. These proteins can have a lot of functions, some act as lego that your body uses to build structures, others function as tiny machines that your body uses to move energy and other proteins around, even others help defend you against bad guys from outside your body. DNA is a lot like a language which has only four letters (C, G, A, T) and uses only three letter words. Special little machines in your cells can read these three letter words and mix the proper amino acid ingredients together to cook proteins. In doing so, they make new machines and building blocks for your body's cells to use. When we say we have \"mapped the genome\", we mean that we have read the entire cook book of several individuals, and written down the recipes in the correct order. However, just because we know how to cook something does not mean we know how it works or what every recipe is for. A lot of current research is focused on understanding what the function of a lot of the recipes is. This is important for several reasons. One is that recipes sometimes become damaged. A lot of times you hear about a genetic illness, it is because the recipe for a particular mini-machine or protein has become damaged, and then your body loses some function. Edit: thanks for the kind words, all!",
"Anyone with a child's microscope and a steady hand can see that there are 46 human chromosomes, arranged in 23 pairs, and that they look like striped, knotted skeins of yarn when stained; anyone with a child's chemistry set can determine that these chromosomes are made of phosphorous, a modified (deoxygenated) version of a sugar called \"ribose\", and four nitrogen-containing, high-pH chemicals (or *bases*): guanine, cytosine, adenine, and thymine. (These all rhyme with *ween*.) Given that we isolate these base-containing molecules as acids, and given that we isolate them from the cell's nucleus, we call these molecules \"Deoxyribonucleic acid.\" Anyone with a sophomore's biochemistry kit can determine that different, *ordered* combinations of DNA's four bases results in different proteins, when exposed to the enzymes and chemical environment of the cell; ask a doctor, and you can easily learn that many human traits (especially diseases) can be diagnosed by whether your body synthesizes a normal, altered, or degenerate form of a particular protein. Those with the altered *protein* must have altered *DNA* producing it; since such traits are heritable by one's offspring, chromosomes must be the mechanism of heredity. (There's other evidence for this, of course - this isn't the order that these things were discovered.) Given that the traits are passed on to new *generations*, we call the part of the DNA that produces a particular protein the *gene* for that protein. What remains is to know *where* on each chromosome each gene is located - how far from the beginning or the end, and how much of the chromosome each gene takes up. The view of the chromosomes from the microscopes could only go so far down, and the view of the bases from chemistry could only go so far up. For decades there as an enormous gap in between into which we could not see. That was really hard to figure out, and it took a lot of chemistry and new machines and new computer algorithms, but once we did it, we had an arrangement of a human's chromosomes and what they contained and where they contained it, and when you [plot it out to look at it]( URL_0 ) you can think of it as a *map*. So when we say we've mapped the human genome, we mean the same thing almost as if we'd said \"we've mapped Toledo, OH\" - we've gone there and figured out what's there and where it's located relative to everything else. Which is not to say that we know *everything about it*, just like how a map of Toledo doesn't tell you everything there is to know about Toledo, either.",
"Think of having landed on North America, without knowing what it is, and wanting to report back on what you have come across. Mountains here, a bay over there, a desert down there, etc. That is a map. Similarly with chromosomes, with a whole bunch of markers on each chromosome, specific genes can be located between point \"A\" and point \"B\" on chromosome \"12\", say. There is another century of work figuring out what it all means. But now there is a latitude/longitude system of sorts for the chromosomes. The map is 20 years old, they've been sequenced as well now, so we have a very good idea of what chromosomes look like. For context, it was discovered long ago that human genomes are 99.9% the same between people. A high level map of one person's genome works pretty well on another person. The differences between people show up in the remaining 0.1%. Source: Nth co-author on two of the mapping papers in the 90s. The North American analogy was our leader's tutorial for the curious.",
"Human beings have a number of chromosomes with DNA in them. There is also DNA in the mitochondria. The DNA is a tremendously long chain of nucleic acids which specify the construction and the operation of human beings. The entire length of the DNA has been read and recorded in libraries for at least five individuals. These DNA sequences are on file in accessible NIH databases. The DNA sequence of almost all species on Earth has not been mapped. Having read and recorded this sequence does not mean we understand it. You could spend your life with a computer accessing these libraries trying to understand a small part of it. The DNA sequences make up genes which were identified long ago before we even knew that DNA was involved."
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5oodtc | Why is there so much got damn static electricity in the winter? | Other | explainlikeimfive | {
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"Cold air has a much lower capacity to hold water than warm air. Water conducts electricity, so when the air is wetter static electricity dissipates through the air more quickly. Thus, when the weather is cold, the air acts as more of an insulator and static electricity builds up more readily."
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5oovcl | Why sometimes people have a single hiccup and at other times a never-ending series of hiccups? | Biology | explainlikeimfive | {
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"Hiccups occur due to an irritation of the diaphragm such as eating too quickly or drinking a liquid too fast. When the diaphragm is irritated it contracts trying to pull air in while the voice box (larynx) and glottis contract and close the airway causing the \"hic\" part of hiccups. It can be caused by a malfunction of the neural transmission to the diaphragm as well, which explains getting the hiccups during high emotion situations or temperature changes. The article in the link does a good job explaining how it begins. [(Hiccups)]( URL_0 ) The diaphragm, larynx, and glottis work in sync while breathing and during hiccups it is out of sync. The reason why it takes longer in certain situations is just naturally how long it takes to get rid of the irritation and return to its proper rhythm or sync. I hope this helps! 😊 TL;DR: Diaphragm contracts when airway opening is closed causing hiccups. Length of hiccups varies based on how long it takes for the airway opening and diaphragm contractions to get back in sync. Edit: Grammar",
"You sometimes only get a single hiccup? You lucky bastard.",
"I'm not a scientist but what I do know is that it has to do with what the hiccup is actually trying to do, if it can't do (insert what it does) it will keep trying. Wish I was that preserving lol"
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5opm3u | Why do some people get sick so often and I get sick only about twice a year? | Other | explainlikeimfive | {
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"You have probably been lucky, and not been exposed to as many contagious people. Do you have much contact with children?",
"There could be a lot of different reasons. Sleep, stress, exercise, age, diet, hygiene. The people in my office who get sick all the time are older, smokers, and overweight.",
"Not an expert but the immune system is important and some people's are not as good as others. For example, increased stress and negative emotions can reduce the antibody response to an illness: [Marsland et al (2001) antibody response to vaccination]( URL_0 ) There are others factors too like diet (vitamin C is good for immune system strength) and exercise and general health lifestyle."
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5opmi6 | basic rules of Dungeons and Dragons? | I always hated on the game but recently I got curious and have been watching full games on YouTube at this point. Im starting to get it (atleast I think) without seeing or reading anything about it. What are the basics that everyone needs to know about it? | Other | explainlikeimfive | {
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"D & D is a game of cooperative storytelling where one person sets up obstacles (a man-eating dragon, a corrupt lord, a booby-trapped labyrinth) and the others portray one or more characters who must defeat those obstacles (a fierce dwarven warrior, a smooth-talking elven archer, a crotchety old wizard). The person who makes the obstacles is called the DM, or Dungeon Master. The core mechanic is the twenty-sided die, or d20 as it is known in the game. For almost any non-trivial thing you want to do (attack the dragon with your sword, intimidate the lord into letting you pass through his lands, disarm a spike trap), you roll a d20 and add or subtract a number based on the character's skill at that task. The DM compares that value to a set number that he or she determined as the difficulty for the task. If you meet or exceed the number, you succeed! If you're below the number, you fail. Generally, rolling a 20 is considered an automatic success as it's the highest number on the die (in some cases a DM may decide it's a success even if the total value doesn't meet the difficulty value), while rolling a 1 is an automatic failure."
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5opn14 | ; if the human body requires calories (from food) for energy, how do energy pills like ProPlus and other caffeine and energy pills work if they're not providing us with calories? | Biology | explainlikeimfive | {
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"Because feeling awake and alert is not the same as having more energy. In every day speech we associate that feeling with energy, but scientifically speaking it's a different thing. Look at it this way, if you're tired you feel like you're low on energy. So you go to sleep, and then when you wake up you feel like you have more energy. But you don't really. You haven't eaten anything in your sleep. You have less energy than you did when you went to sleep. Caffeine is a drug that suppresses the feeling of being tired. It doesn't actually give you energy.",
"There's a difference between energy and alertness. Certainly low sugar can make us feel less alert, but tiredness does it much more. So in the case of caffeine, for example, it blocks the receptions for our tiredness hormones. As a result our brain can't \"hear\" our body complaining about being tired and we are more alert. Long term use can cause serious problems, though.",
"Your brain accumulates adenosine over the course of a day as a signal you need sleep. Caffeine is a similar shape, and binds to the adenosine receptor, but doesn't trigger it. This blocks the signal from happening. As a result, taking caffeine makes you feel refreshed, as it blocks the tiredness signal."
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5oprlh | What is the difference between sound, light and electromagnetic waves and how do they coexist without scrambling each other ? | Physics | explainlikeimfive | {
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"There are really only two different concepts here. Electromagnetic waves (of which we call a small section of frequencies \"visible light\"), and sound waves. Electromagnetic waves can travel through empty space. Sound waves are the ripples of some type of \"stuff\", most familiar of which to us is air. They don't interfere with each other because they do not share the same stuff being disturbed (or oscillated). However, sound waves most certainly can interfere with other sound waves and the way that waves interfere is addititive. Think waves in water riding over other waves in the same water. They can also cancel when being added. Think noise-cancelling headphones. Electromagnetic waves can also interefere with each other. Think radio statio crossover."
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5oprsi | how are english speaking kids taught to read? | well you see i'm biligual and they taught me how to read in spanish, and they way they do that is by teaching you how does each consonant sound when you add a vowel, so they teach you how does ba be bi bo bu sound then ca ce ci co cu, cha che chi cho cu, da de di do du, and so on until z, then you can easily connect the sounds of a word, because each combination of letters only sounds one way, but when i think about it that doesn't really work in english(does it?), unless you want to give kids nightmares, so how do they teach you? | Other | explainlikeimfive | {
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"I'm a pre-kindergarten teacher in the United States who teaches children the alphabet, letter sounds, and how to read. This is how I was taught to teach children to read English, although there's obviously lots of other teaching methods used. For the most part, I find this process works pretty well with the vast majority of my students: 1. Teach the student the names of the letters and what they look like. 2. Teach the student the sounds of each letter. We generally stick to the basic, most common sounds first. For example, I teach: A says ah like apple, E says eh like egg, I says ih like itch, etc. Even though those letters make other sounds, I don't complicate it yet. 3. Teach the student to sound out specific words called CVC words (consonant-vowel-consonant) words. These are words that ONLY follow the sounds you taught. So words like cat, bat, bet, zip, etc. 4. Once the student has a good grasp on this, you can begin to introduce the irregularities that English has-- double long vowels (like bee, see) and magic e (as in make, bake) and all the other countless irregularities English has. I'd say that most students in the USA who are taught this way learn steps 1-3 in pre-kindergarten and/or kindergarten and step 4 in 1st grade and beyond. To add to the complexity, from steps 2 onward you're also teaching students sight words. Sight words are words that can't be sounded out because they are impossible to sound out, would waste time if we had to keep sounding them out every time, etc. Students memorize these words. These are words like-- the, he, she, they, we, are. Sight words are taught at all levels in a student's education, and there are actually lists of sight words for different subjects all the way from pre-k to college. Hope this helped! It was long-winded but I very much enjoy teaching reading!",
"There are two broad approaches to learning to read English. Many children learn English phonics. Most English words use similar single sound letter combinations, and this approach starts with the most common ones later adding the exceptions which must be memorized (under this approach these exceptions are usually called sight words phonetic learners will learn a few sight words at a time). The other approach is the whole language approach. Under this approach readers learn to read, by speaking, listening, and reading a few words at a time. This approach is much more top down where students learn to interpret meaning even if they don't understand a passage word for word (and hopefully continue to learn additional words to parse increasing nuance in more complex passages).",
"Language education changes rapidly these days, depending on the research. I'm Australian, born in the 90s, so I can only speak for people like me. They taught us that A E I O U are vowels, saying it was 'the core of a word'. They taught us some of the common consonant-bridges like 'th' and the rest was mostly trial and error. As you may know, there are many exception rules in English with the most common example being Y. Sometimes Y is a vowel (eg: easil**y**) and sometimes it's a consonant (eg: **y**ear) We were taught that vowels are needed for a word. We were taught what sound each consonant made. We were taught what sound a vowel made, then we were taught (over years) all of the little exceptions and nuances. #TL;DR English is fucked"
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5opubz | Why haven't we figured out a way to restore lost enamel on teeth? Or artificially fill in the spaces with something inert that our body wouldn't reject? | Biology | explainlikeimfive | {
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"text": [
"I actually just read about a new drug they are working with that helps grow new teeth. URL_0"
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"https://www.sciencedaily.com/releases/2017/01/170109092624.htm"
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5opw1c | How did Scientists guess the number of atoms in the universe? What makes us think that number (10^78 - 10^82) is correct, or close to correct? | Mathematics | explainlikeimfive | {
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"Atoms in the universe is a Fermi problem. You take certain assumptions and then do the math. A similar question would be \"how many barbers in NYC\"? To solve that, you would say that there are 9 million people in NYC, half are female, so they don't use barbers, making it 4.5 million barber clients, say that men get haircuts on average 10 times a year, so that's 45 million haircuts, and that a barber does an average 30 haircuts a day, and you end up getting 50,000 barbers in NYC. Any of these assumptions may be off, but they are all close enough that your answer will be within 10-20%"
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5opx72 | Why do some customer support numbers say "except for Panama"? | Technology | explainlikeimfive | {
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"dclek98"
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"text": [
"It seems that Panama has historically had a lot of call centers. I think the issue is that Panamanians are supposed to call a different local number instead of the regular 800 number."
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5oq05p | Why can't an operating system contain kernels from multiple operating systems, allowing programs from either OS to run? | I understand that applications are dependent on frameworks and components provided by the OS in order to run, but isn't the kernel responsible for allowing those frameworks and components to operate in the first place? Couldn't an operating system made from several kernels run the applications from several operating systems? | Technology | explainlikeimfive | {
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"Because kernels expect to have direct access to the hardware. If you attempt to run an OS kernel as a regular program under an OS, first it will fail because the kernel expects to be loaded differently than regular OS programs (usually a kernel is loaded by a small program called a *bootloader* which is written to the first sector of the disk, which is what is loaded by the BIOS). But that's fixable, the kernel is just bytes after all. It's pretty trivial to write a regular program that runs under an OS, puts the bytes of the kernel code into memory, and then executes them. There are some more technical hurdles to get the kernel code actually running [1], but the fundamental problem is that the kernel code will try to directly access some hardware devices. If the OS is running in an environment with hardware protection -- as modern OS's generally do -- it will terminate the kernel process with an error when it attempts to directly access hardware. If the OS doesn't have hardware protection, the guest kernel will succeed in its attempts to access the hardware. But the problem then becomes that the guest kernel and host OS each expect to have exclusive access to the hardware, but in reality they're both sending and receiving commands to the hardware. Lots of incorrect usages of the hardware means that the system will quickly become non-functional. One approach to solve this is to have the host OS mediate access or provide virtual hardware devices to the guest kernel. This is called *virtualization* and is very popular because it saves lots of money -- buying a new physical computer is pretty expensive, but running a new virtual machine in a physical computer you already have is basically free. Three common virtualization products are Xen, VMWare and VirtualBox. Another approach is to re-write the kernel to talk to the operating system instead of trying to access hardware directly. It's no longer exactly a kernel, it's more of a user mode program. This is the approach taken by User Mode Linux, a way of building the Linux kernel to produce a program that can be run under an operating system. [1] One problem specific to PC's is that an x86 processor starts up in *real mode* which is a 16 bit environment. Some ancient operating systems (i.e., DOS) are actually written to run in this environment. But any mainstream PC operating system less than fifteen years old will only have a little bit of real mode code, the sole purpose of which is to set up the processor to switch to *protected mode* which is the 32-bit or 64-bit environment used by the vast majority of the kernel code and user applications."
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5oq2wq | Why do we, as humans, mostly stop crying from pain at a certain age? Usually around puberty. | Biology | explainlikeimfive | {
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"Crying is a primitive way for babies to communicate \"I have a problem and I need help\" before they know language. As they grow up, and are capable of getting attention in other ways, or handling the issue themselves, they no longer need to cry. The other aspect is the social component. As people get older they are expected to handle problems without crying, and often looked down upon if they do. As most people do not like being looked down upon, they try not to cry.",
"What does this say about adults who still cry at the drop of a hat? I have friends that still cry over anything like at least once a day. Movies, a random song, the new, etc will trigger them."
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5oq303 | What does it mean when physicists say the universe is "flat"? | Physics | explainlikeimfive | {
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"You know how you can draw a triangle on a piece of paper, and the internal angles add up to 180 degrees? That only works because the paper is flat. If you were to draw a triangle on a curved surface, the internal angles *wouldn't* add up to 180 degrees except in very specific circumstances. The angles might add up to more or less than 180. That's what is meant by \"the universe is flat.\" The geometry of the universe follows the principles of Euclidean geometry (flat geometry), not curved geometry. As a practical example, what this means is that if we see a star, we're sure the star is pretty much in a straight line in that direction (barring some *very* strong source of gravity that causes an effect called \"gravitational lensing\"). If the universe were curved, that wouldn't necessarily be true."
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5oqigq | what happened in Dunkirk? | Other | explainlikeimfive | {
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"Basically, the french had a big defensive position (called the Maginot Line) along the German border. The French could have defended that position relatively easily. So the obvious way the german would have attacked was like during WW1 through Belgium where there is not as much defensive position like Bunkers. So the French and English positioned most of the division there to stop the Germans. The problem is that there is the Ardennes Forest between the defensive position of the Maginot Line and the bulk of the Franco-British forces in belgium. This region was view as impassible for a modern army. You can make your canons and truck go through a thick forest with no road. The problems is that they didn't understood that tanks were now strong enough (remember is was just a 20 years old technology at that time) to just go through the forest and create a path on their own. So now the French and English forces in Belgium were encircle by the German forces at the german/belgium boder, and those that went through the Ardennes. The only place to escape was by sea so these forces retreated to ports and boast kept taking these men to England. Dunkirk was the port were most of this evacuation took place.",
"Some good explanations so far, but they miss a few important details. So World War II starts when Germany invades Poland, which falls very quickly. During that time they were also at war with France and Great Britain, but for several months there were no battles on the western front. The British sent in the British Expeditionary Force (basically the bulk of British forces, with the best training and equipment) to support the French by holding the line along the Belgian border. The assumption was that the Germans would do what they did in WWI and try to rush through Belgium, which they did, but this time it went much better for them than in WWI. The German army smashed through Belgium in days, instead of weeks, and the French army simply crumbled in the face of German forces. The Germans moved with a speed military minds of the time thought impossible, over ground they *knew* was impassable, and it became clear that France simply wouldn't hold. The British didn't have the men or material to hold against all of Germany by themselves, so they had to retreat. The problem was that the Germans were outflanking and pushing in on the Brits with astonishing speed, and the German air force had complete control of the skies. There simply wasn't time to evacuate everyone in the normal fashion. Even with every ship available helping, it wouldn't be enough. So the government put out a call for anyone with a boat to cross the channel and evacuate anyone they could. Thanks to the bravery of the more than 900 civilian ships who showed up to help, along with the desperate rear-guard actions of a number of divisions (most of whom were killed), the overwhelming majority of the BEF (nearly 340,000 men) were evacuated over the course of 6 days. What often doesn't get put into perspective was how much the British lost in material. The BEF had lost *every single one* of their tanks, armored cars, and personnel carriers. The RAF lost 900 planes, half of them fighters, and the Royal Navy lost 200 ships. 68,000 men had been captured or killed. More than **120,000** vehicles had been lost of left behind, along with 2,500 artillery pieces, 100,000 guns, and more than 500,000 tons of supplies. The loss of equipment was simply staggering, to the point that the bulk of the British army was completely combat ineffective. So, while most people consider Dunkirk to have been a major victory for the British, in reality it was only a success in that things could have been far, far worse.",
"WW2 starts and eventually Germany invades France. Fighting goes poorly for the Allies and a huge number of them get trapped in Dunkirk, a port on the English Channel. The only way out was to try and evacuate as many soldiers and materials as they could. To do that the British Navy got a ton of civilian boats and ships to participate as well. Tons and tons of troops were evacuated but it was still a big loss for the Allies and sealed off Western Europe from the Allies for a long time. But in retrospect the evacuation may have also saved the Allied/British War effort despite the loss of materiel. It allowed the allies to consolidate their gains and come up with a real plan to take back France."
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5oqmss | Does climate change lead to an increase in extreme cold weather as well as extreme warm weather? If so, why is the average yearly temperature continuing to get warmer? | I've heard that the term "Global Warming" is a misnomer because really not everywhere on the planet is getting warmer and that there can be cold extremes as well as hot ones, leading the term "Climate change" to be more accurate. Any truth to this? If so, why is the earth's average temperature increasing instead of the extremes balancing each other out in terms of a yearly average? | Biology | explainlikeimfive | {
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"That's a little backwards. Global warming means all storm systems are larger, in addition to the obvious that average temperatures are very slightly higher. However, larger storm systems means that cold fronts that used to die out as they head south will go much farther, bringing freezing weather to places that infrequently freeze. Thus, a little warming can produce more extremes, including extremes of cold.",
"Global warming is a misnomer and leads to confusion and misinformation because you also have extreme cold weather which make some (a lot?) of people question the validity of the scientific community's claims. The phenomenon needs to be talked about more in therms of energy. The energy the Earth receives from the Sun is pretty much constant what changes is the amount that remains trapped in our system versus what gets reflected and radiated back in space. Greenhouse gasses offset the balance causing more energy to remain trapped further fueling weather events and their extremes."
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5oqx81 | How come some countries go from million to billion when counting, while other countries have an additional step? | Personaly I'm from Norway and when we count we go million-milliard-billion-billiard and so on. What has caused this split and which is the most common? | Other | explainlikeimfive | {
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"It seems like we have different definitions/translations for these words. From my googling, in Norway, million | milliard | billion | billiard is equivalent to English million | billion | trillion | quadrillion, which both line up with 10^6 | 10^9 | 10^12 | 10^15. This is a result of \"long scale\" vs \"short scale\"; Romance languages (and others, including Norway) tend to use long scale, in which each \"major\" step (million, billion) is another 10^6, while English speakers use short scale, in which each major step is another 10^3 after the first 10^6 (million)",
"You're talking about Short Scale vs Long Scale number systems ( URL_0 ) The split isn't easy to pinpoint exactly, but it falls largely along linguistic lines and geographic regions. There was an attempt in 1948 to create a standard and bring everyone to the Short Scale (million-billion-trillion) but it didn't go through."
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5or3ds | How does the black line on debit/credit cards work? | I've taken it for granted for a long time and now I'm curious. | Technology | explainlikeimfive | {
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"text": [
"It has a magnetic texture that is unique to your account. Machines read it and know which account to access. Extra sentence."
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5or6yo | How can locks/padlocks be mass produced whilst still being unlockable only by their individual key? | Technology | explainlikeimfive | {
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"I'm going to try my best to explain this, but it can get complicated. To understand how this works, you would need to understand how a key cylinder is made and how the key interacts with the cylinder. We'll use a 6-pin cylinder as an example. Starting with the key, as you know there are several grooves along the side of the key. This designates the keyway. Each keyway is usually specific to a manufacturer like Schlage or BEST. When you look at the cylinder on a lock, where you stick your key in, it isn't a straight line, it's a series of jagged shapes that correspond to a keyway. Typically keyways are designated by a letter, for example \"C keyway\". This is done so that a key with the C keyway grooves will not work in a cylinder with an A keyway. The notches on a key correspond to the pins inside the cylinder. There are 6 pins in their own chambers within the cylinder. In each of these chambers there is also a spring so that when you take the key out of the lock, the pins will return to their original position. When the key is inserted into the lock, the grooves push the pins into alignment allowing you to turn the key and unlock the padlock. The pins in each chamber vary in size and are placed in a sequence called the bitting format (I'll touch on this later). The various pin sizes are given a number 0-9, zero being no pin and nine being the largest pin. These pins are placed in a sequence to create a combination. Keys are cut to these different combinations so that one key doesn't operate every lock. Now, remember that bitting format? The bitting format is a sequence that allows us to come up with 4096 possible combinations. How did I come up with that number? Using the 0-9 size pins I mentioned earlier, you would put a different sized pin in each chamber. For Example: 965857 965859 965851 965853 Each of the 4 combinations above have to be operated by a different key (assuming there is no cross keying or master keying, but that's another time). When coming up with these combinations, it's important to note that no 2 numbers in the sequence can be the same when they are next to one another, which is why I left out 965855. Since this is the case, there are only 4 possibilities per sequence group. Since there are 4 possibilities per group and 6 pins, 4^6 is 4096 possible combinations. Out of those 4096 there also arises the issue of ghost keys, which are keys that are so close to another combination that it's possible for them to accidentally unlock another cylinder. This is why your friend's key will sometimes work in your lock. Typically there is keying software that eliminates these groups before the bitting list is finalized, but when things like padlocks are mass produced, they reuse the same bitting format because of the limited number of combinations. So to bring this all back around, because of the different pin combinations in a cylinder, there are around 4096 possible combinations (minus ghost keys) that can be used when mass producing padlocks. They are all operated by a different key that is specific to the padlock's keyway. I realize this is too much information and there were some points I didn't touch on...but it's fun to explain.",
"The lock has a set of pins of various sizes that when lined up correctly allow the lock to turn. Depending on the lock, there's usually about 4-6 pins. For a 5 pin lock, let's say there are 15* different pin sizes that can be put in any permutation. The number of permutations P(15,5) gives 360,360 unique locks. During manufacturing they just rotate through different pin sizes either at random or according to a process which ensures that no two identical locks end up in the same lot. \\* 15 comes from looking up the number of sizes in a Schlage pin replacement kit. Some pin replacement kits have up to 28 sizes which would result in 11,793,600 unique pin sets for a 5 pin lock, or 271,252,800 for a 6 pin lock.",
"They aren't unlockable by an individual key. It's rare but your house key can open up othe houses as well. The amount of houses you'd have to try before it would work would be an amount that you'd probably be arrested before you succeeded.",
"Most people don't realize that not ALL locks and keys are unique. Even autos have keys which duplicate those of other similar brands. It's just it's so rare that a key to one car will start another, it's not often seen. But it does occur. Same is true for house keys. If people REALLY knew how easy it was to pick a lock, they'd think twice about buying cheap locks....",
"This past year I purchased a house and decided to purchase all new locks around the house. Went to my local hardware store purchased about $100 worth of door handles to find out they all worked with my old house keys after I installed them all. Couldn't believe it.",
"While there are some good answers here, the dirty little secret is manufacturers and consumers (industrial or otherwise) are kinda lazy, and many things are simply keyed alike: [From The Eleventh HOPE: \"This Key Is My Key, This Key Is Your Key\" by Howard Payne & Deviant Ollam]( URL_0 )",
"There is a limit to the number of possible keys for any given lock series. Any given lock has a number of spring loaded pins that can have a small number of positions, the cut of the key moves the pins up and down to align break points with the edge of the lock cylinder so that the lock can turn. A cheap lock might have 4 pins and each pin has 5 possible heights that it can be cut to. Such a lock would have 5^4 possible combinations, which would be about 500 different keys. a more well made lock might have six pins capable of 10 positions, and that would give you 10^6 possible combinations, or 1,000,000 different keys (that said, a lot of combinations near all high or all low would tend to be avoided- you wouldn't want to be able to open the lock with what was essentially a key blank) high security locks may have additional features like angled teeth that rotate the pins to a necessary position, which adds another dimension for potential unique keys, as well as making picking the lock much more difficult. --edit-- that should be 4^5 on the cheap lock, for 1024 combination, and thanks to the kind soul who pointed out my mistake to me."
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5orfc3 | Why are Hawaiians and other pacific islanders so much more prone to obesity than other people? | Biology | explainlikeimfive | {
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"It's a recent change, mostly attributed to a shift from traditional diet to high-calorie processed food. Many islands don't have enough workable land to sustain the current population with fresh food. Some have also suggested cultural support for being large plays a role."
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5orjtw | Why do some foods taste much better hot, while others taste much better cold? | Other | explainlikeimfive | {
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"Most of what you taste is about how things smell. When you're eating something that's warm, you get the smells escaping from the food better as it's hotter, and the chemicals that make the smells evaporate off the food, or are drawn up in steam. For some foods this is great! Think about how good fresh bread just out the oven smells and how it tastes a million times better than it does when it's cooled down (not that room temperature bread is bad... But fresh stuff is amazing!). But for others, this might cause chemicals to be released that don't smell so good. Warm ham, for example, smells quite odd. Most foods that we eat cold are quite refreshing. So the coolness is part of that. What is also vital is how the food feels in your mouth. For example, sausages that are fresh out of the oven have a completely different texture to cooked sausages that have been in the fridge, as the fats congeal. This too is part of how we enjoy our foods."
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5orknu | My Mum hates it if I spend a few hours gaming, yet if I watch TV for the same amount of time, so doesn't mind. Myis this; how is gaming worse for you than watching TV? | Technology | explainlikeimfive | {
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"Honestly, it is not worse for you. But people unfamiliar with gaming probably think it's weird and don't understand what you are doing. And the fact that it's so immersive -- like you don't want to be interrupted or talk with your Mum during the game -- may annoy her."
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5orljl | Ideal gas equation questions | 1. Why does the equation have that constant "R"? When we were to derive the equation somehow, why would have to include that constant "R" somewhere? 2. What is that "ideal gas"? And if the gas we were talking about wasn't an "ideal" one, would the equation not work? Thanks in advance everyone | Chemistry | explainlikeimfive | {
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"An ideal gas is considered ideal due to individual molecules having no volume. This means that the gas is infinitely compressible, something not possible with a \"real\" gas. Eventually a real gas will become a liquid or solid, which an ideal gas won't. Additionally, ideal gasses don't have molecular interactions. That isn't to say reactions don't take place, but rather there isn't a repulsive or attractive force between the molecules. At atmospheric pressure, this is a great approximation... The molecules are all far apart so there are minimal forces. But increase the pressure, and ideality breaks down. Usually in school the first time this is introduced is with the van Der waals equations, which give a rough approximation. Further studies can bring you far more complicated equations such as peng-robinson or more, which include values of how non-spherical the molecule is (acentric factor). R is a unit conversion. It starts off as Boltzmann's constant and is multiplied by Avogadro's number. Boltzmann's constant is the amount of energy per unit of temperature."
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5orn0d | How does electricity find the path of least resistance, and can this be used to solve the Traveling Salesperson problem? | For those who don't know, the Traveling Salesperson problem is a pathfinding problem: given a set of points as inputs, find the shortest path that hits all points and returns to the start. Seems to me like electricity already does this | Physics | explainlikeimfive | {
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"Lets say we have a battery and three node. For the TPS, we can go: * Battery, 1, 2, 3, Battery * Battery, 1, 3, 2, Battery * Battery, 2, 3, 1, Battery * Battery, 2, 1, 3, Battery * Battery, 3, 1, 2, Battery * Battery, 3, 2, 1, Battery So, you're suggesting we connect all of these patterns at the same time? Cool, lets do that. But guess what? We've got a lot of redundant movements, right? We go from 1- > 2 in examples 1 and 5, we go from 1- > 3 in examples 2 and 4, we go from 2- > Battery in examples 2 and 5... We don't need to put 2 wires for those, right? Give me 3 minutes to draw this in MS Paint... [Alright, I'm back]( URL_0 ). Now, do you see the problem? We set this up, what happens? The electricity will take each path, sure. Lets say we follow the first example above. We're going B,1,2,3,B, right? Well, we go B... to 1 along the blue wire... then the path of least resistance would most likely be following the red wire immediately back to the battery. Lets try a different one. We go from B, to 2... and immediately back to the battery... It doesn't matter if you increase the resistance of the red wires. There's still more resistance in Black+Red wire than in Red alone, so red is still the path of least resistance. **But lets pretend that doesn't happen somehow.** The next problem we would face is... how do we separate the currents? Sure, we start at B. Some current (lets assume an even amount) follows each blue wire to its next point. Then, those all follow black wires to *their* next point. But, at the same time, there is still current coming out of B. So, that new current mixes with the current coming from a black wire, then evenly distributes it again over all the new paths that are available. How do we distinguish the current coming along the blue wire, from current coming along any of the other wires? **Okay, then lets run them one at a time.** So, we run each simulation once, to find out which is the shortest? That's an NP problem. We already know we can do this. The TSP is about finding out a way to do this without having to test every possibility.",
"Electricity doesn't just follow the path of least resistance; it follows *all* possible paths—but the amount of current following each path is proportional to how well that path allows it to flow.",
"Computer engineer here, Electricity does not follow the path of least resistance, it follows all paths. The lesser the resistance, the greater the current. The electromagnetic field is defined at all points in space. It also propagates very quickly, at the speed of light in a vacuum. As the field propagates, the current density at a particular point in space changes as a function of the strength of the electric field and the material's resistivity."
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5orobz | Why is it that sitting on a toilet seat for a long time causes/inflames hemorrhoids, but a comfort measure is sitting on an inflatable ring (same shape/pressure) | Title pretty much says it all. If you have hemorrhoids, you are instructed not to sit on the toilet for long periods of time. A comfort measure sold for hemorrhoids is an inflatable ring, that seems like it would put pressure in the same spot as a toilet seat. Why does the ring not have the same negative impact as the toilet seat? | Biology | explainlikeimfive | {
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"Toilet seat: hard rigid plastic Inflatable ring: soft, pliable, squishy, flexible, air-filled donut. They're not the same at all. The only thing similar is the shape sort of."
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5orooc | Why are younger children so picky about the foods that they eat? | Biology | explainlikeimfive | {
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"I remember having a course on evolution and behaviors where we were taught that children are picky with vegetables because in nature, a lot of plants are toxic and children tend to avoid them, especially since children are more fragile in case of an eventual poisoning. Moreover, a lot of green vegetables have a bitter taste and this tends to be an indication of toxicity in plants. As adults, we lose our sensitivity and therefore our aversion for bitterness, and we just learn what is safe or not to eat. Add to that some other factors, like cultural aspects (advertising for instance, fastfood restaurants), or the fact that humans have a natural tendency to favor energy-rich food (for evolutionary reasons that are not really \"useful\" anymore when you live in a developed country).",
"Children are much more sensitive to new sensations than adults are. Every new thing is a learning experience and their brains notice and absorb absolutely everything they're exposed to, which can be overwhelming. New foods can be intimidating to kids, not just because it's different, but because it's an explosion of sensory input - appearance, taste, smell, texture, temperature, etc.",
"For the same reason they cry bloody murder at the slightest startling noise or pinch / physical pain....because they lack experiences to compare it to. a pinch on the arm wouldn't make an adult flinch, but for a small child, thats likely the most pain they have ever felt.",
"I read somewhere that there are 2 main conflicting concepts that are hard-wired into human brains: 1) eat food that is different, because what you've been eating might run out. 2) eat food that is the same, because other food might make you sick And until the children grow old enough to over-ride these instincts, they can be inherently picky/choosy/unpredictable in what they'll eat.",
"Tell that to my boy. He's 4 and apart from too spicy food he'll eat anything. Favourite snack: a whole raw tomato. Loves veggies, mild curry, risotto, fruit, the works. In retrospect we should have know what was coming when he was a baby and we gave him some tart lemon slices to chew on, hoping for a funny reaction. He ate the lot without a care in the world."
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5orrvu | Tesla released all its patent on their car in 2014 so that anyone can use them. Why isn't there any other Car Co. using them ATM? | Technology | explainlikeimfive | {
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"There is no way to know they aren't. There are a lot of patents and licensing that you would have no way to check on who is using what and How. Also using a Patent doesn't mean it will look like Tesla, that is a different thing.",
"Any number of manufacturers easily could be using various parts and concepts invented under a Tesla patent and you'd never know it. As far as you know the latest Ford Hybrid is using the battery charging systems of a Tesla, and Ford-Original everything else. Nobody's told you because the particular design of the alternator isn't exactly flashy in a banner ad or sales pitch. Nor is admitting that another company does something better than you. If you're wondering why nobody has taken ALL the Tesla patents and made a clone, that's just business. Tesla is already having trouble finding markets for their vehicles. Even if you skip the most of the engineering, as a new manufacturer you'd have to still pass all the regulations and safety standards and figure out exactly how to buy/make the exact parts required for the whole car. THEN you could START marketing your new car, and MAYBE find some buyers. This represents billions of investment to make a vehicle that would now be 5-10 years out of date (depending on how long it took you to solve the startup problems), and still have a tough time selling against a cheaper, newer, and arguably better standard transmission vehicle. And consumers expect you to repeat the entire operation within a calendar year to produce the 2020 Edison (that they still won't buy)."
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5orv3u | How do certain parts of the world have so many undetonated landmines? | Other | explainlikeimfive | {
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"> More specifically, how is it possible to place so many mines in certain locations and areas? It isn't necessarily someone going out and carefully digging a pit and setting trip wires for every mine. Instead if you wanted to mine an area you could add a trigger delay of a few minutes and just throw buckets of mines out the back of an airplane flying over the targeted zone. The mines scatter and come to rest before their trigger becomes active, and now it is extremely hazardous to travel in that area. > and do they just assume they'll never use that land for anything other than deterrence? Yeah, you don't generally mine areas that you plan to mess around in. That would just be silly. > Who is making all of these mines? The military industrial complex! Factories can make mines just as easily as bombs and bullets. > Has their usage been effective in terms of warfare and zone control? Certainly they are effective. The main problem is that they remain effective even if you don't want them to be. Suppose the two sides fighting come to a truce, then a peace agreement. The mines don't know that! And due to the number and method of delivery it is likely that nobody really knows exactly where the mines are or even if they are still functional."
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5orzei | If text messages are encrypted, how can government agencies access them? | Technology | explainlikeimfive | {
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"The communication between your cell phone and the cell tower is encrypted, but it is not end-to-end encrypted between your cell phone and the other cell phone. That means that there are three people that can read the message: you, the person who controls the cell tower, and the person you're sending the message to. If the government controls the cell tower (by using a cell site simulator, commonly referred to by the brand name \"Stingray\"), or compels the telecom company that owns the tower to give them the messages, they can read them.",
"Encryption is between a sender and a number of recipients. Typically, as in this case, you are the sender and your service provider is the recipient - NOT your friend's phone. That is the nature of your relationship between you and your provider. So the recipient, your provider, has *plaintext* access to your message and delivers it on your behalf to a 3rd party, your friend, via his phone. The encryption scheme is only meant to keep unauthorized 3rd parties out. For example, anyone with the equipment can listen in to the radio signals from your phone, but they're not the intended recipient, so your message is guarded against them. Likewise, the internet is composed of networks, and your message may have to traverse a network your carrier doesn't own to get to its destination. Your carrier encrypts between itself and it's destination across that 3rd party network so all they see is the *cyphertext*. But never forget you're talking to your carrier, not your friend; you don't own the radio frequencies, or the right to broadcast on those frequencies, and you don't own the network your provider carries your message on your behalf, they do. They have unencrypted access to the communications you establish with them. There are applications that encrypt messages between you and your destination directly, but you need to be able to build and install ALL the software yourself, from the OS up, because these phones are untrustworthy closed platforms that may and historically have and probably still do contain backdoors, all the way down to the hardware level. So in conclusion, cellphones and proprietary platforms and software are inherently insecure and untrustworthy."
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5os4r9 | If I had $10 trillion and wanted to pay off the U.S.'s national debt, whom do i pay? | Economics | explainlikeimfive | {
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"Bondholders, which means you technically can't pay the debt off early. When the US borrows money, they hold an auction, in which people give them 10,000 (usually in large multiples of $10,000) for the right to receive a few interest payments per year and $10,000 when the bond matures. These bondholders can be almost anyone (it's likely tough for Cubans to collect) and the bonds can be resold on the secondary markets. The US collectively owes whomever owns the bonds at any given moment (which includes almost everyone via mutual funds that own at least a few bonds). The US pays its debts because it wishes to maintain it's stellar credit rating (the US has never defaulted on a debt in it's entire history). That means when the US wants to borrow money, nearly everyone in the world is interested in lending money to the US.",
"> Most important, whats the need for US to be paying back its not that someone is going to come and foreclose. > If the US stops paying its debts as planned, folks are going to stop buying their bonds. Should they ever want to raise cash through debt again, nobody's going to buy their bonds again without some kind of (expensive) garauntee. A large-scale example is Dubai in the UAE. Seeing their oil reserves drying up, the royal family started converting their largest city into THE Muslim tourist destination. Turns out after certain world events Muslim folks don't always feel welcome in Paris or Disneyworld. They set out to build 7-star resorts, rediculous luxury activities, some of the tallest towers in the world, and even fabricated whole designer islands. At first this was all financed by the royal family, but as that cash dried up they sought out foreign investors. When they started having cash flow issues due to a lack of tourists, they simply stopped paying debts. Tons of people got hosed, but as you said nobody can really repossess a whole country, and invading a small non-militant country is really bad mojo on the world stage. So almost overnight Dubai's construction progress virtually halted, as nobody was lending to fund further development. Another consideration is that world debt brings world peace. The US famously owes China trillions. That means we're paying trillions worth of interest payments each year in debt service. Should we go to war with China, you can pretty much garauntee that we'd cut those payments off the first day and zero the debt in our books. That's a massive blow to Chinese income, so whatever they're willing to go to literal war over would have to be worth the hit.",
"First, who owns the national debt? A pretty large part of it, about 20% is actually just one department of the government owing money to other departments. It's not unusual for one department to borrow money from other departments in order to fill in budget shortfalls. The next 40% or so is held by US citizens and companies. These are in the form of US Treasury Bonds, which are a type of savings bonds that anyone can buy. If you own the bond, the government owed you that amount of money with interest, due on the date the bond matures. The remaining 40% or so is owned by a mix of foreign governments, companies, and individuals. This is also in the form of Treasury bonds. In theory, you could go out and buy $10 Trillion dollars worth of these bonds from anyone willing to sell them and then formally forgive the debt. I'm not sure what this process would entail, but it might be as simple as destroying the bonds. It could be much more complicated though.",
"The government actually has a website that allows people to make direct gifts to the U.S. Treasury to pay down the debt. The website is available here: [ URL_0 ]( URL_0 )",
"You can just pay the US treasury, [they have URL_1 ]( URL_0 ) to let you do it, they accept credit, debit, ACH, paypal and check via mail. In practice, as others said, it's not instant, they technically put it into a fund reserved for paying off bond holders, and the treasury pays out as they come due, if it was $10 trillion I'm sure lawmakers would find a way to withdraw it before the treasury pays down that debt. As for forclosure, not possible, a bond is something that says \"I owe you $x on this date\", if you say you want it back early, they don't really have to pay. And if the US did default, there isn't really anything anyone can do about it, the US government controls their bonds, and there isn't any higher authority they answer to (unless you count the rest of the world going to war over it). In practice, it's bad for the US if it happens, if they failed to pay it, the mutual funds owning the bonds would simply end up zeroing out the bonds that went unpaid, vaporizing money out of the fund, and everyone with a retirement account would be upset about losing money.",
"Please bear in mind, if you pay off the US debt, it will immediately accrue more debt since it now has a nice chunk of money to spend. The US (and most other) governments *are* paying their debts. It's not as though we are in a spending free fall and about to go dead-beat. This is merely the situation politicians frequently try to put to their constituents to discredit 'the other team' rather than an actual comprehensive overview of governmental debt.",
"> How do countries pay national debt? They pay to bondholders, who bought US treasury bonds. Every once in awhile, the US (or other country) essentially hold an auction, and people who want to buy bonds, do so. After buying them, they'll get paid back according to the return on the bond > Whom do they owe to? It depends on the country, but most owe it to citizens, and some foreigners. If i recall, ~60-70% of the U.S debt is owed by US citizens. > Most important, whats the need for US to be paying back its not that someone is going to come and foreclose. Mainly in order to be able to borrow in the future. As a sovereign nation, they can basically tell creditors they're screwed, and there's not much anyone can do to stop that. However, this would obviously hurt people's trust in the countries' ability to pay in the future, and they'll have a harder time selling bonds in the future (usually they can still sell bonds, but they have to offer nicer terms to make up for the chance they're going to screw creditors again). > whom do i pay? While you can't buy out the bonds directly * , there is a form on your taxes where you can pay more than you owe to the Treasury. * technically it depends on the bond. Some have buyout clauses, though you would have to pay extra for the privilege. but especially in the U.S. case, they don't *want* to be paid back early. It's safe, free profit for them (although the return is rather low. iirc Treasuries right now are going for something like .5-1.5% . better than nothing though)",
"It's important to also note that the USA should absolutely never pay off all the debt. Issuing and buying back treasury bonds are how the USA (and every other sovereign nation) controls inflation. There is (generally) a finite supply of us dollars in the world. When the USA sells bonds, they take payment in USA dollars and put them in the federal reserve. This reduces the supply of money, you have a smaller amount of money chasing the same number of goods, so prices go down a bit (or don't rise as quickly, deflation). Conversely, if the USA is buying back bonds, they are pushing out more us dollars, so there is more money chasing the same number of goods, so the prices go up. In order for this mechanism to work, there has to be a supply of, and market for bonds. When this is uncontrolled, we get the kind of ridiculous inflation and interest rates seen in the 70s.",
"Couple things that need to be added to this conversation. Technically, you would be paying a broker. The way it works is you pay a broker, than the broker calls other brokers to find a seller. To keep the math simple, let's say you pay 1000 a bond, the seller get 950, and the other 50 goes to the brokers that facilitated the deal (in finance, this is called a spread). Supply and demand applies to bonds, so if there's less of them, they get more expensive, so it could cost you more than $10 trillion (realistically probably would) to actually sop up all the debt. When a country pays its debt, it buys its own bonds then \"takes them out of circulation.\" Also, you would not only need to buy up all the debt, you would also need to forgive it. Otherwise all the debt would just be owed to you, which wouldn't help the US financial solvency at all. US debt is also considered the bedrock investment of the world. As trash as our friends across the pond like to talk, they still see US debt as the most secure investment in the world (suck on that, Merkel). Treasury bonds are often traded to hedge risk in derivatives trading. Foreign governments like to hold US bonds for safety. Pricing of almost anything, including the stock market, is based on the rates of T-Bills. I worked for a company that advised mergers and acquisitions in Latin America, and T-Bill rates still were a piece of the analysis. There's a huge question as to where financial markets would go if all the debt just vanished. There would be no \"foreclosure\" (fuck, can you imagine? \"Haha, you didn't pay your debt. Now China gets some nukes.\"). The US would go to court, lots of lawyers and advisors would get paid, and some type of agreement would be reached. For example, maybe creditors accept 80 cents on the dollar. However, when the US would want to borrow again, the rates would be exorbitant, and would hamper economic activity (even a fiscal conservative will agree with this). Countries need to borrow, it's an essential piece of the economic puzzle. Also, remember what I said about how everything is priced off US debt, how US debt is used in so many things? All these things would go into turmoil. Almost everyone predicts it would be some type of pandemonium, but I'm not sure anyone really know. TL;DR 1. They buy it from the market. 2. Literally whoever buys it, including investors and other governments 3. Because otherwise bad things will happen.",
"I think a better answer is, even with 10 trillion dollars, You still wouldn't be allowed to pay off the national debt. Paying off the national debt would actually be a really bad thing for the US. Basically think about money properly. It's the most useless thing on the planet really. You can't eat it, burn it, build with it. So you need everyone to believe that money is actually worth something. Now take into account that each country has their own money. Other countries taking out US bonds, makes other countries invested and want the US bond to be worth something, so they can spend that borrowed money elsewhere. This is a very simplified version. Should no one be invested in dollars, then maybe you can't buy as much abroad in dollars and would have to exchange them. Who to exchange with? Who would want your dollars if they will struggle to buy things with them? So the dollar is now worth less. However, Flood the world with dollars via bonds and you make your currency much more attractive. Do this for long enough and eventually entire markets run off your made up and self-controlled currency, like the oil market. As currency is totally made up and country controlled, it takes the rest of the world to play the same game for it to keep working. However, if one person sees an opportunity to stop playing for its own advantage, IE, a middle East country trying to trade oil in gold instead of dollars, and the US is not happy and may go over there to stop it happening. A similar thing can happen in the stock market. It doesn't take anything to actually happen to collapse the stock market. However, let's say bill gates decided to cash in all his shares and he said it's because the stock market is going to collapse. The others start following. Very quickly everyone tries to sell and the stock market collapses very quickly. Everything relies on everyone else playing the game. You and your 10 trillion ends the game and not everyone would want to start playing again, especially as the US has created such a self-gain.",
"> What form does US debt usually take? It usually is in the form of bonds, which are auctioned off and largely bought by the privately owned federal reserve mainly, then the privately owned banks in the west, and finally foriegn countries and their central banks. > Who do you pay? The privately owned federal reserve Banks, mainly who buy the majority of the US government bonds. When they pay them, they buy assets with that money and create inflation slavery and theft by inflation. If you had 100k in dollars, and banks double the money supply. Prices of everything doubles. Now your 100k only buys you 50ks worth of stuff. So banks effectively stole 50% of your savings through inflation. if you worked 30 years to save 100k, they stole 15 years of your life. > How do they pay the debt? When the bond matures and payment is due. They borrow the money from the federal reserve at interest, enter the auction market and buy it with thr cash created and printed into existence by the federal reserve. It's a never ending debt cycle. US government borrows money from private banks who create it out of thin air, to buy up debt it borrowed before that was also printed out of thin air. Plus interest. Kind of imagine a pay day loan scam. Where you have to borrow from the pay damn loan company to pay back the initial money you borrowed plus the interest. The effect ia you get deeper and deeper into debt and debt ceiling keepa getting increased and more and US dollars keeps getting created and given to the privately owned federal reserve and their subsidiary banks like morgan stanley who spend it buying up stuff like houses, stocks, shares, oil, gas, gold, 3rd world resources, etc. > Why do they need to pay the debt? If they don't the privately owned federal reserve stops printing money and stops lending money, creating a financial collapse. If 1 trillion US dollars are circulating to keep everyone employed, paid, and economy running in usa. And banks reduce that money supply by 10% they can create a recession, and if they keep restricting the money supply more. They can create a depression. In 1930s they reduced the money supply by 40% or 55% according to some stats. In order to create an economic collapse so that they could buy farms and companies for cents on the dollars. >",
"Is $10 trillion enough to pay off the debt? I thought the debt was much higher than that.",
"> How do countries pay national debt? By issuing out IOUs (treasury/government bonds) to lenders. Example: Country A needs 10 billion dollars. Country B lends 10 billion dollars to Country A and in return Country B gets 10 billion in IOUs that say Country A must pay back Country B (plus interest) within a certain amount of years. > Who do they owe? This is the most important question. The U.S. owes everyone that owns a U.S. IOU/treasury bond. That's a lot of countries, funds, and people. I'll lump everyone into three categories for the sake of ELI5. (~50%) The US public and private sector: Social Security Fund, other federal government funds, mutual funds, US banks, private pension funds, etc. About 15-20% of the debt is owed to our social security fund. All that cash taken out of your paycheck goes straight into the fund, which then lends out all of it to the US government (itself). This means the social security fund has trillions of dollars of US government IOUs that can become completely worthless if they never pay the money back or the US runs into some sort of hyperinflation. There's a whole discussion right now about the social security fund and whether or not millennials will actually see any of that money. Some people even think the baby boomers that are retiring over the next decade won't see everything that they're promised. (~35%) Foreign government: China and Japan own most of the foreign US debt. (~15%) Federal Reserve: The Federal Reserve is actually a private owned institution that has more power than any government or other institution in the world. Why? Because they alone have the power to print more US currency. What do they do with the currency they print? You got it! They buy US government IOUs. In addition, in 2008 they bought all those worthless mortgage backed securities from the big banks so that they wouldn't all go bankrupt. > What's the need for the US to pay back it's lenders? Put it this way, a US government IOU is a US government IOU; there's no real distinction between one IOU and another. The US can issue 10 billion in IOUs to China and promise to pay them back within 10 years; if they don't pay them back once the 10 years are up then it'll put into question all other IOUs the US has issued. Japan can be like, \"well if they didn't pay China why would they pay us?\" Following that line of logic Japan and everyone holding IOUs would try to sell them. An IOU worth 10 billion could sell for ten dollars if everyone believes that the US won't actually pay the money that the IOU says they'll pay. This situation is what people would call a bond market collapse. Something to note: bonds have always been the safe haven asset just like homes were before the 2008 collapse. There's a lot more to this stuff but hopefully this covers the ELI5 audience. EDIT: spelling",
"Federal Reserve. They can buy and sell. In most cases they act like middlemen. So even though a debt is owned by Chinese or UK, they do end up in Fed if needs to. Fed create liquidity aka actual dollar you use at your local walmart. But it won\"t pay down the debt. When you pay off 10 trillions, the market will have 10 trillions less debt. Which means there are 10 trillions actual dollars foating around. Now government wants those money. They cannot aĺlow it to foat around. So Treasury will sell more debts to soak up all those extra dollars. In effect you transfer your 10 trillions from your bank account into US government account. Then poor people will demand a cut of those money. And it will go into useless and wasteful programs like more obamacare or bridges to nowhere....or start another war to justify spending those 10 trillions. The final result of uoir generosity is that people will find things more expensive and US government now owes more debt than before you pay off the 10 trillions. You are better off using that money yourself. 10 trillions under the control of a single private person is much better than under a group of people with zero accountability. Bush 2.0 and Obama already gone through your suggested exercise. Just that in this case it was Fed that gave the free 10 trillion dollars.",
"Most of it would go to all US taxpayers.... US taxpayers are the largest holders of US debt. URL_0",
"Hard to ELI5 this one. * US gov't borrows money * They do not borrow from banks * They do not make monthly payments * They sell 5 year, 10 year, etc treasury bonds * The bonds have a percentage extra you get at the end of the number of years you buy them for * Buy a 5 year bond at 1% for $1000 = 5 years later you turn it in, get your $1000 back plus 1% interest. * No one can collect on the bonds early. It is not a bank loan. * The US gov't doesn't miss making payments or pay interest only and defer bigger and bigger bills * Most of what you hear about US debt that scares you is wrong * Most buyers of debt are investors who put some of their money in treasury bonds because it is considered safe in that form, and it grows a little. * Investors are citizens of the US, businesses, and other countries including Canada, the UK, Japan, China, etc."
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5os773 | why does it seem when we get sick with a cold or flu it always seems to happen overnight. For example, we always wake up with a stuffy nose or wake up with a sore throat or just wake up feeling unwell when we're coming down with something. | Biology | explainlikeimfive | {
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"Hi! The infection itself happens a several days before you feel the first symptoms (so not in the night before you get sick). The cold and the flu are caused by different types of viruses that are mainly spread via aerosols and bodyfluids. After the infection, the virus needs some time to replicate in your body. That can take approximately 3-21 days. The onset of the symptoms can be at any time, but as you described, many people feel the first symptoms in the morning. And that's mainly because of the stresshormone \"Cortisol\" in your body. It has a lot of different functions. One of them for example is to suppress (- > \"decrease\") your immunsystem activity and inflammatory processes. The amount of the secreted Cortisol is timedependand. The highest level of Cortisol in the blood can be measured around 8 o clock in the morning, the lowest concentrations can be measured in the evening. So that' s the main reason why symptoms feel worse in the morning than during the rest of the day."
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5os86r | How does alcohol negate consent when the same argument can be used when to defend serious criminal offences when intoxicated? | Other | explainlikeimfive | {
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"There are a bunch of answers here, but the reality is that this is a super touchy topic precisely because of the point you are bringing up - why would it appear that sexual assault has a different (and some would argue, one-way) standard as compared to other crimes involving alcohol. To the best of my knowledge, it is ***extremely rare*** to be found innocent of a crime (eg robbery, assault, B/E, etc) due to being drunk. I'm sure you can find one-off instances in front of the occasional sympathetic judge, but I'd guarantee those are rare. However, 'I was drunk' is often a mitigating factor when determining both the charge (eg murder may go down to manslaughter due to drunkenness impacting the perceived intent) and the punishment/sentencing. A lot of times a judge will agree to a plea that includes alcohol monitoring and/or counseling. But its incredibly important to see that 'reduced sentence due to intoxication' is vastly different from 'found innocent due to intoxication' To the issue of sexual assault: Its important to remember that drunk sex (even very drunk sex) is perfectly legal **in the eyes of the law**, despite what you may read on Jezebel on hear on a campus. From a legal perspective (and I'm speaking in general b/c laws vary by locality), if one party is passed out unconscious - this really isn't up for debate - that's textbook sexual assault (as an aside, the DUI comparison is interesting, though, because you can be passed out in a parked car and get a DUI). If you were passed out in the back of a car that, while you were passed out, was used to commit a robbery, there's a 99% chance you won't get charged (really the only reason you'd get charged is to pressure you to flip on your friends - then the charges would be dropped). It gets slightly murkier when one party claims 'I was blackout drunk' but they are still coherent and still capable of agency *at the time*. The legal standard for 'coherent' is pretty vague in practice and if you're walking around and able to follow somebody back to your/their home, you're 99% going to be found to be 'coherent'. This is going to be controversial, but here goes: A high standard for 'coherent' is a good thing and the courts do not want to criminalize drunk sex, nor should they. However, this is a huge part of the reason that some advocates feel that cops and the legal system don't prosecute enough sexual assault cases. In practice, 85% of these cases turn into a 'he said, she said' that no court is capable of deciding. So cops don't purse them. Advocates think the system is unfair, but the reality is that drunk sex is perfectly legal (again assuming one of the parties isn't comatose drunk - we aren't talking about Brock Turner). In my view, the advocates are wrong - 'alcohol made me have sex' should be no more of a plea of victimhood than 'I only robbed the 7-11 because I was drunk' or 'we were drinking in my living room and later I was pressured into robbing the 7-11'. The parallel justice systems being set up under Title 9 considerations at Universities in the US are an absolute travesty to justice, and if you don't believe me, read the open letter that the professors at Harvard Law School wrote on the topic in addition to the hundreds of legal articles on the topic. Edit: to add that drunkenness may impact the original crime that's charged",
"If one party is drunk and the other member is not, you're dealing with a situation where one person is in a weakened state and can be taken advantage of. In this case, the perpetrator is the one who is sober and is fully aware that they are taking advantage of another person. For criminal offenses where someone is intoxicated (say a DUI), theres an assumed amount of responsibility that the driver has. After all, they weren't coerced to drive and if they were going to drink, they needed to have a plan to get home (ie designated driver/uber/etc). (Ps not a lawyer, but this is my understanding of why they are different)",
"past a certain point, being intoxicated means you are unable to give consent basically saying you are lacking the mental facilities to realize what you are doing. for criminal offenses, some defenses utilizes the fact that the person was so < intoxicated, driven by rage, etc > that they were not mentally aware of what they were doing. so the two basically amount to the same thing, the person was in a state of mind that they were not able to comprehend what they were doing.",
"You are looking at it backwards. If I'm drunk, and get assulted, the fact that I was intoxicated doesn't negate my attackers actions. They still committed assult. Likewise, you as a citizen, must get consent before engaging in sex with someone. The other person's level of intoxication doesn't change that. Intoxicated or sober, you must get their consent before engaging in sexual activity. If you fail to do so, it's considered rape. So, we as a society have decided that one cannot consent to sex while intoxicated. Therefore you cannot get consent to have sex with an intoxicated person. No consent, and your actions become rape. The other person, your partner, isn't getting a pass due to their intoxicated state. You are being held to the same standard at all times. If you fail to get consent, it's rape. That's true if your partner is drunk, high, unconscious, resisting, or stone cold sober."
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5osa98 | Why is there a seemingly larger risk of getting viruses on a laptop/desktop than there is while accessing the internet through a smartphone/console? | Technology | explainlikeimfive | {
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"Consoles and some mobile operating systems (iOS) are \"sandboxed\". This means that only authorised code can run, for example in iOS you can only run apps signed by Apple from the App Store; unless you jailbreak it. Consoles are the same. On normal computer you can do whatever you want, which allows bad stuff in.",
"With great power comes great responsibility. A home computer is pretty much anything goes, which is great for people who needs lots of options. A smartphone or console is much more limited in what it can do, so it's harder (but not impossible) for bad software to get in.",
"The existing comments are all great ideas. I would add this: Think of what you might target as a producer of malware, whether that's ransomware or otherwise. Going after end users is not going to be profitable. End users don't often have the cash to shell out to ransom their files. So malware producers target businesses that can shell out large sums of cash as ransom (either because they have no backups, have bad backups, or it's cheaper to ransom the files and restore than to recover the backups). With certain industries there may be trade secrets to steal and sell, or perhaps a state-sponsored malware attack on the strategic utility or industry. And what do you know, those bigger players all run Windows. Even if they use Linux servers, workstations are the way to get at the file servers easily and efficiently. And users are still the #1 attack vector.",
"All the comments here are absolutely correct. There are a ton of reasons why laptop/desktops see more viruses than smartphones and consoles. I would say the top two reasons said by u/Gnomio1 and u/ckindley argue that creaters of malware are going to focus there energy on what gives the greatest return. On top of that it comes down to the type of data. PCs (even most enterprise servers/storage) run block or file data. Mobile devices (excluding consoles here) tend to access data through object storage. TL;DR basically means PCs are predictable and the ways we access than is well known. Mobile devices are still new. It takes someone who keeps up with modern programming languages to attack. So at the end of the day there are fewer people who know how to attack mobile devices and it's more cost effective to go after PCs. Combine the two and there's your answer."
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5osc8r | Why, as an 18 yo in California, my parents need to sign a waiver allowing me to sign myself out of school or sign anything for myself. | Other | explainlikeimfive | {
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"because that's the contract between your school and your parents and you as a minor. as an 18yo, you can drop out of school, if you don't like that."
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5osj3g | What would a videogame look like if you could see the world as it was loading? | Technology | explainlikeimfive | {
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"Depends how it's drawn. Like when you draw a picture do you draw it in pencil and then paint it? Or do you draw a little bit and paint it and then draw a little bit more. I believe it was wolfenstein which was the first game to render maps in low quality and then quickly re render in higher quality as the user would look at certain sections (to appear higher quality in areas of interest to reduce computational load)",
"Every game is different so this is going to have as many answers as there are game engines... For the most part though, it's going to look like crap."
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5osmyf | Why is China so capitalist when the country is one of most well known communist states on Earth? | In 1949 China was formed as a hardline communist (or perhaps rather socialist) state. Why does the reality today feel so different? | Economics | explainlikeimfive | {
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"China hasn't been communist since the early 90's. it's more capitalistic than alot of western countries now. the ruling party is still named the Communist Party, but their doctrines are now mostly government oversighted capitalism.",
"Communism really didn't work for them after a time. The people, especially those in power, saw the amount of luxury available in a capitalistic society and decided to slowly make the switch over. It's possible that the ruling party saw that the switch was inevitable, and decided that a controlled slide into state run capitalism was better that a chaotic revolution forced by the population.",
"Because in reality there are no purely capitalistic states or purely communist ones. It's hard to entirely regulate and control an industry as a state and it's that much more difficult to control ALL industries in a country. Similarly, there are some industries that are so important to the public well-being and national security that it would be foolish to for a state to avoid regulating them extremely heavily or outright controlling them. Examples include basic utilities, transportation, and communications. When talking about socialism, capitalism, and communism, I think it's important to keep in mind that no state really embodies any single ideology fully. With regards to China, Deng Xiaoping took control of the government after Mao's death in the late 1970s. He instituted \"Socialism with Chinese characteristics\", which basically said that China would be socialist and make use of the market economy. They theoretically justified this by saying that Communism requires a stage of socialism first and that outright eliminating private ownership moves too quickly. Instead of having a failed attempt at that, China should instead become a socialist state that phases out private ownership and moves towards Communism. Remember, Marx thought communism would grow out of capitalism and that capitalism was a necessary stop on the way to communism. Party leaders at the time also said that the transition would take a long time, perhaps upwards of 100 years, so they gave themselves plenty of time to adjust. I don't know enough about the topic to say whether party leaders really believed they were staying true to their Communist roots when they opened up the markets to some degree or if they were just trying to justify doing what they thought would be best for the economy."
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5ospcf | Why does oil seem most abundant in dry, desert areas and how did it get there in the first place? | Other | explainlikeimfive | {
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"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",
"It's not really. You seem to be forgetting the massive untapped oil fields in middle of Gulf of Mexico and Alaska.",
"The reason middle eastern oil is so sought after is the ease of access. The oil in that region is typically found very close to the surface. Compared to other parts of the world, like the Gulf of Mexico, its practically accessible with a straw.",
"Oil doesn't all come from the desert. There is a *lot* of oil in the arctic circle. Alaska has a lot of oil, as does Norway, and many places more. There's also a lot in jungle areas as well. As to how it got there, well, the surface of the Earth is significantly different to how it was 500 million+ years ago. Oil, often referred to as \"fossil fuel\", comes from fossilized plant material, animals (like dinosaurs, though little oil would actually be dinosaurs), and microbes in the oceans. While these dead things went further into the crust, the surface of the Earth changed: the climates changed, the tectonic plates moved, etc. So places like Saudi Arabia, the North Sea, Venezuela changed on the surface, but the fossil fuel was still there. What you're probably confusing is that a lot of the world's oil comes from the Middle East because it is very easy (relatively speaking) to draw it to the surface, but the most of the oil in the Earth isn't *in* the Middle East. Edit: and there's a lot of oil in Oceans, too.",
"There is actually a ton of oil in the oceans. But considering the Earths climate has changed from say 65 million years ago, those desert places could have been home to an abundance of life which over time had died and turned into oil. Also it's easier to go out drilling in the middle of no where than in the middle of a forest, since you would have to clear the environment.",
"Dry places like the North Sea? Alaska? Venezuela? Angola?",
"It's not - people are just unwilling to wreck all their food and water sources anywhere else. There's oil deep underground from old life forms buried and pushed down and squeezed so hard their molecules became the hydrocarbon chains we need in oil & similar products. The process is well known enough we can now make oil artificially doing the same thing, and diamonds too."
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5osrk6 | What does "Right-to-Work" mean? | I have been hearing the constant argument regarding RTW and I have been trying to follow articles. It just seems so controversial, that it's hard for me to get a direct answer or understanding. It just passed in KY and looks to be passing in MO. I see a lot about Unions and Union workers, does RTW only impact Unions? (I don't have much experience in regards to Union jobs so I'm pretty lost here) | Economics | explainlikeimfive | {
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"When a union is formed, it cover all employees in the relevant field at the workplace. So if you work on the floor of an auto manufacturing plant and your colleagues vote to unionize, your job is now covered by agreements with the union whether you voted to unionize or not. Similarly, when a union negotiates for new employment terms with management, those terms will apply to you. Running a union costs money. Someone has to bargain with management, organize workers, hear and process grievances, etc. and those people need to be paid. The money comes from union dues which are paid by union members. Since unions negotiate for all covered employees whether they are union members or not, failure to ensure that all employees pay the union leads to something called the free rider problem. The issue is that employees may try to get a free ride by benefiting from union negotiations (since they are covered by the agreement between the union and management) without having to pay union dues (since they aren't union members). Unions tried to address this through something called \"union security agreements.\" These are agreements negotiated with management that say things like the company can only hire union members or all new employees have to join the union. Some types of union security agreements are illegal (e.g., the US doesn't allow the \"closed shop\" where employers are required to only people who are already union members), but not all of them are. The most common form of security for unions in the US is the \"fair share\" provision. This says that all covered employees have to pay dues to the union for the unions essential activities. Essential activities are union activities that all employees benefit from, such as collective bargaining. It doesn't include things like the union magazine or union get-togethers. The idea behind this system is that employees who benefit from the union but don't want to join have to reimburse the union for what it does their behalf, but nothing more. Right-to-work laws ban union security agreements. They basically say that workplaces can't require employees to join or pay any dues or fees to the union. Unions can still exist in these states, but as a practical matter they're very, very hard to maintain because of the free rider problem. tl;dr - When a union covers a workplace, it negotiates for all employees whether they're union members or not. Since negotiations cost money, the union can negotiate with management to require all employees to pay the union for work it does on behalf of all employees whether they're union members or not. Right-to-work laws prohibit workplaces from requiring non-members to pay, which essentially makes it impossible for unions to get enough money to operate.",
"In a state without RTW laws, a business and a Union can come to an agreement that says that everyone who works for the company below management must be a member of the Union. Anyone who is hired after this agreement is signed must join the Union as a condition of their employment. Failing to do so means getting fired. RTW laws essentially outlaw this kind of agreement, so that it can't exist. Because the company can hire non Union workers (which are cheaper and easier to deal with), the Union is severely weakened. Without representing ALL of the workers, the Union has much less bargaining power.",
"Right-To-Work means that state law prohibits collective bargaining agreements between unions and employers that require all employees to pay dues to the union, regardless of whether or not the employee wishes to join the union. Proponents of RTW laws state that it returns some power from the unions to the employees, and it gives all employees a choice of whether or not they want to participate in the union without losing their job. Opponents of RTW laws state that it weakens unions by reducing the operating budget of each local, since some employees in RTW states opt out, which gives the union less power in negotiations with the employers."
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5osvu1 | Whats that called at the end of a commercial where the guy talks really fast about warnings and stuff? | Other | explainlikeimfive | {
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"One such word that could be used to describe the end of a commercial where the guy talks really fast about warnings and stuff is \"disclaimer\" although a disclaimer could also just be text."
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5ot0ss | How is temperature measured and considered to exist in space? | So with going over concepts such as absolute zero and the definition of temperature in chemistry, it got me wondering how it is calculated and defined in space? Basically I was wondering how we perceive it because there is no atoms or molecules to move around in empty space, doesn't that mean that any specific section of it is at absolute zero? I get that heat can be transferred through cosmic energy from the sun and other stars but if there is nothing to move because of the heat, doesn't that make it have an absolute zero or nonexistent temperature? | Physics | explainlikeimfive | {
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"Believe it or not, a lot of space is actually pretty darn hot! In fact, there are clouds of gas/plasma that surround large galaxy clusters that can reach up to 10 million degrees Kelvin. Wow! An environment like this provides a useful example to answer your question: \"Temperature\" of a gas (most of space is gas/plasma) is really a measurement of the kinetic energy contained in that gas. In other words, it's a measure of the average speed of each of the individual gas particles. Think about a room full of children as an analog for a container full of gas. If the kids have a lot of energy and are running around really fast then that gas is \"hot\", if they are tired and just sitting there then that gas is \"cold\". So what would you feel if you put your hand in some of the intergalactic gas that is 10 million degrees? Probably nothing. The reason is that, while each individual gas particle has a huge amount of energy, the density is so crazily low that not many of them hit your hand and transfer energy to it. In the children analogy, hot gas in space is like a huuuuuuge room with only a few kids running really fast. So how do we actually _measure_ the temperature of gas in space? Unfortunately the answer is very complicated and depends hugely on what type of gas you're talking about and how hot it is. The short, mostly accurate answer is that things that are hot tend to cool (even in space) and the cooling process almost always results in some sort of emission that we can detect and measure."
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5ot22k | Are food products that say "consume within 7-10 days after opening" basicslly a food poisoning gamble after day 7? | Why not just say consume within 10 days if there isn't a slight risk after day 7? If there is a risk after day 7, why not just leave it at 7? | Other | explainlikeimfive | {
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"usually, that is a freshness date and not a you will die if you eat it after date. If properly stored and packaged, most food doesn't have germ risks before you open it. But something like a cookie could lose its taste or firmness or whatnot. Once you open something all bets are off. You have to be really careful to keep it at the correct temp. Like if you leave out cheese dip for hours it can get germy. If you eat it again later you could get sick.",
"Food spoilage isn't a black-and-white thing. Certain variables like your fridge temperature, how long you let the food sit out at room temperature, or even your stomach could dramatically affect how long it's good for. To give a real-life example: I was having a huge problem with spoiling food in my fridge. Milk was going bad a week before its expiration date. I finally realized that the temperature was too high, turned it down to near-freezing, and suddenly the milk lasts as long as it's supposed to. As a manufacturer, how do you account for that?"
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5otffr | Where does fear come from and why do different people fear different things? | Other | explainlikeimfive | {
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"Fear is your body's way of warning you of mortal danger. Given enough 'fear', you'll produce adrenaline to help you fight or flee the danger. The way you learn to recognise something is by association. I don't need to be bitten by a shark to be afraid of it - because I've seen it (or the information has reached me somehow), so I'm afraid of being bitten by a shark. People are afraid of anything that has directly hurt them, or has been inferred to them that it will hurt them"
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5othqt | . I heard that you burn quite a few calories when you orgasm. Is this true? How or what is burning all those calories? If say someone started masturbating/having sex multiple times a day would they lose weight? | Biology | explainlikeimfive | {
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"No, it is not true. Sex itself can burn calories, but that's because of the moving around (physical activity), not due to orgasm. If you have vigorous sex several times per day, it will burn calories, but it's unlikely to be enough to lose a significant amount of weight. As with all of these types of questions: the ONLY way to lose weight is to burn more calories than you consume. Diets, pills, and supplements that claim to be able to boost your metabolism enough to cause you to lose more weight are lying. Your weight is 85% what you eat, and about 15% your exercise. It's quite possible to be thin and sedentary, and it's possible to have a lot of excess fat and still be very strong.",
"There's a lot of variables here, and I'm not going to do a deep dive into the literature, so based on two articles with no sources, a male orgasm burns 3 calories, and a female burns 60 to 100 additional calories in a 30 minute sex session where she reaches orgasm, above a baseline of 100-200. My guess would be that this is more of an indication that more vigorous sex is required on average for a female to achieve orgasm, and not that the orgasm itself burns 60 calories. It 's several seconds of muscle contractions, how much energy could it realistically consume? Then there is caloric intake to take into account, but let's assume that a person is in caloric balance where they are eating roughly the calories that they burn over the day and their weight is stable. Is twenty minutes of masturbation a day going to help you lose weight? Probably not as much as twenty minutes of walking. Sex is likely to involve quite a bit more physical exertion than jerking/flicking it, so I'd say it beats walking but loses out to jogging in all but the most extremely vigorous of circumstances. So yeah, theoretically you could lose weight by adding sexercise to your daily routine, but the contribution that is due solely to the orgasm itself is going to be minimal. Edit: AND this requires that you were at caloric equilibrium before you added in the additional physical activity and that you're not skipping leg day to go to pound town.",
"Nobody has touched on the \"calories\" males literally expel. In terms of nutrients required to create, what caloric value would an average male ejaculate contain, and can we count this towards caloric expenditure despite it not being \"burned\"? Herein may lie the key to losing weight through having a tug."
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5otmu1 | Do cell phone companies limit/throttle data because there actually is a bandwidth shortage, or is it a cash grab? | Technology | explainlikeimfive | {
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"The incentive to throttle bandwidth is 1) Generally to ensure everyone using the network has a decent speed 2) To try to limit the growth of data usage. There is only so much data that can be passed through a antenna/radio. The limits are simply physics. Typically, the higher the frequency, the more data per unit time can be transferred. The downside being higher frequencies do not travel as far, nor do they penetrate buildings nearly as well. As more and more people use data more and more intensively, there comes a point when no one can use anything effectively. If you have ever shared wifi, you know what happens. Someone is watching a HD stream, meanwhile, the total available remaining bandwidth is reduced. The two most common solutions are adding more frequencies used (ie adding more data channel). This is very expensive as new antennae must be installed, new radios added (very expensive on their own), etc. And each frequency has its own quirks. The second option is adding more towers to a network. Which is far more expensive then adding equipment. As well, while the cost of data falls every week for cellular providers, they must balance extracting every last dollar they can from their customers against providing effective service to those same customers. If your provider gave truest unlimited data, even for a high price, very soon everyone would start using more data. Eventually this causes everyone on a tower to have download speed issues, as there simply is no room left within the spectrum for data transmission. This is why cell company's deploy temporary cell sites at large festivals. Otherwise there network gets slammed, no one can send a text, let alone place a call and everyone gets angry at their phones. The cell companies are currently undergoing a massive upgrade. Several (several!!!) new frequencies are being added. Source: I work in the industry. Also, if you are not afraid of working at heights, willing to work away from home (a lot), you should consider a career change. The industry is booming and a lot of places are having manpower shortages. Plus the pay is good. God bless overtime. Source: Overworked guy dealing with industry wide labor shortages."
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5otupv | Why are bulletproof vests not reusable? | Technology | explainlikeimfive | {
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"The easiest way I can explain this, is a kevlar vest is like a cube of jello? If you smack the jello and crush it, it will break apart, but absorb the shock, if you hit it again it's just a pile of mush so it will barely stop your hand, your hand being the bullet.",
"Because the vest can stop a bullet only if certain parts of it are at full strength. When a bullet goes though it the layers will weaken as they stop a bullet. In fact some of the layers are designed to breakdown as they get struck by the bullet. As they those layers degrade they absorb a lot of the force of that bullet. But if I have a new vest and a vest that has been shot a few times, the used vest will give much more unreliable protection. They new vest will be far more reliable.",
"They are not bulletproof, they are bullet resistant, that resistance goes down each time they are struck and eventually they will fail and bullets will pass through them."
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5otvqt | What is a memory? | Other | explainlikeimfive | {
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"This sounds like a broad question, but I believe it isn't. I do not know if there is a scientific answer to this or not, so please take into account that I have chosen to compose the explanation I am about to launch into entirely by memory. Therefore, if I have any of the facts wrong and someone corrects me, it will serve to show a direct example of it's unreliability. What is memory? Another way of asking this question is: what is learning? All learning requires memory. All memories are learned. However, they are not the same thing. Learning is the act of building knowledge, understanding, and wisdom through actively using memories, whereas memory is the data drive. If learning is the artist, then memory would be the paint. They are two sides of the same coin. With this as a foundation, the next obvious question is: Q: How does learning/memory occur? A: I haven't the foggiest idea. Most likely a scientist would say something about neuron pathway formations, but I am not a scientist so I'll leave it to one of them to work with that. Instead, how about another question: Q: What kinds of memory are there? A: In our day to day experience, there are several types: -Short term memory. A memory stored for only a short amount of time and then forgotten, usually within 30 seconds or less. When you memorize your friend's wifi password and then forget it immediately, this is short term memory. -Long term memory. This is a memory that sticks with you, usually for life. Most long term memories occur in conjunction with emotions or senses, like the scent of fresh bread, or your first kiss. When you sleep, your brain rifles through the memories of the day and chooses which ones to store and which to discard. This is why it's harder to remember periods of sleeplessness, and why it's more effective to have enough sleep while studying for finals. There are also many, err, species of memory: -Sense memory. A memory catalogued and triggered by any of the five usual senses. -Emotional memory. A memory linked to a particular mood or emotional state. These are the kinds of memory associated with emotional triggers, for example. -Ancestral (genetic) memory. As far as I understand, this is the idea that major events leave their mark somewhere in your genetic sequence and these marks are passed down through your family line. -Abstract memory. Recollection of previously considered ideas and concepts, as well as new juxtapositions of all memory types. Imagination. -Muscle memory. Memory gained principally through repetition of an action. However, one can create muscle memory by \"white rooming\". If I remember correctly, this was originally a martial arts technique. To do this, one imagines oneself in a white space performing the motion one wishes to learn. You have to imagine that you really feel yourself doing it. I've used this to improve at playing guitar while riding the bus, for example. It takes a bit of practice to get the hang of, but it can effectively cut the required to learn skills by a significant amount. Muscle buildup is another form of muscle memory. -Spatial memory. The recollection of a previous spatial awareness. This is how you know that something has been moved on the table, or that the couch used to be over there. -False memory. Memories are suspect. Each time we access a memory, your current experience and point of view acts a lens through which you see it. While you retain the original memory, you create a new memory of viewing the memory, and events occuring within your environment, sensations you are experiencing, emotions you may be feeling, etc, will have changed it. Next time you access the memory you may end up with either or both, and it just gets crazier from there. -Forgetting. Although most people consider this to be the opposite of memory, this is not the case. In order for us to be able to orient ourselves in the moment, forgetting is vital. There is an excellent RadioLab sequence about a man with total recall. It did not end well for him. Imagine that you have total recall. You see a puppy. Yay! The next day, you see anther puppy. Seeing the puppy brings up the entire experience of the first puppy in perfect detail. An hour later, someone mentions puppies. Your flawless memory has you experiencing both of the previous puppies, and now also the entire event of the conversation surrounding them. In five years every encounter with a puppy will be insanely chaotic with perfect memories, each one compounding onto itself, since total recall means a total lack of hierarchy to one's memory. Moreover, each emotion felt, each touch of fur, each sound of a bark, each smell related to puppies, and the way every one of them looked would all be there. Total recall would be a curse. There are other kinds that I won't go into here because they generally have to do with more esoteric ideas, and aren't everyday experiences for everyone, easily observable, or may not exist. Ghosts, for example. I think that how we learn is also a very interesting question, but since this is already very long and likely riddled with errors (did you catch any? :D) I'm going to stop here."
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5otvu6 | Why can you become "blackout drunk"? Why can't you remember anything after? | Biology | explainlikeimfive | {
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"Your body is basically shutting down (to prevent you from drinking more poison/speed recovery from the amount you already drank). The same way a computer shuts down and there's the blue screen before it turns off, you enter that \"windows is shutting down\" area in real life where your body is taking over for you, and you don't remember because memory isn't the priority when you've been poisoned/are about to die. The same way documents arnt saved if you shut down your pc with them running, it's worried about closing programs not saving data. In a little more real terms, the alcohol interferes with receptors in your brain responsible for many things including the areas for memory, it affects everyone to a different degree and increasing consumption adds more interference, making you lose more and more memory until you potentially lose the whole night.",
"There is a way to recover those memories but you may not like it URL_0",
"I don't have much knowledge about this, but I remember it being discussed in a neuroscience lecture that the brain stops forming long-term memory when you black out, i.e. it's not that you forget, it's that you never registered it in the first place. If you've ever experienced a black-in, which is when you suddenly show up somewhere (not by waking up from sleep) and you don't know how because you were blacked out before then, it fits with that explanation as well."
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5otw9f | why we can't just siphon the excess CO2 causing global warming out of our atmosphere and into space? | Physics | explainlikeimfive | {
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"So far, every method of dealing with CO2, whether siphoning it off into space or capturing it, takes more energy and thus creates more CO2 than it gets rid of."
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5otxb2 | What it means to "remember the face of your father" | I mean in the Dark Tower series by Stephen King. I don't remember if it's ever explained in the books explicitly, and I know the idea always confused me. Why do they call it that? Is it honor? Integrity? Warrior spirit? | Other | explainlikeimfive | {
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"Gunslinger culture is patriarchal. Doing something dishonorable was disrespectful not just to your father but all fathers. Someone who has \"forgotten the face of their father\" has acted dishonorably.",
"The idea is that, at least in Roland's culture, that most sons were taught lessons by their fathers, and learned from them. They were raised and taught how to act by their father from a very young age, which passed on both behavioral beliefs, spiritual beliefs, and traditions. To \"forget the face of your father\" is to act outside of those beliefs, outside of what you were taught. It's seen as equal to abandoning all the lessons and teachings you were raised by. To \"remember the face of your father\" is to make sure that those teachings are remembered in everything you do, guiding how you act and what you do."
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5otxym | Why does shaking hard-boiled eggs in water make them peel so easily? | As demonstrated here: URL_0 I just tried it myself and it worked like a charm. Why? | Other | explainlikeimfive | {
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"I imagine it's like pouring vegetable oil onto a bull rider as he tries to hold on. Eventually the liquid is going to get in and help the separation take place.",
"Probably works similarly to the garlic trick. URL_0 With the egg, the water likely creates a buffer preventing you from smooshing it too much while cracking the shell and loosening the membrane around the egg."
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5ou3s3 | If it takes two days for food to eventually be pooped out, why do some foods make me instantly have to go? | Biology | explainlikeimfive | {
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"I remembered reading about this a while back ago and had to do some googling to find his answer but /u/jiggity_gee did a pretty good ELI5 on this. Edit: This is mainly about diarrhea than regular poop. \"So your bowels are like a long train track and your food is like a set of cars on the track. Transit time between Point A, your mouth, and Point B, the chute, is a bit flexible but normally operates on a regularly scheduled basis. When you eat, you put cars on the track and send them to Point B. As these cars go to Point B, they lose passengers (nutrients) at various points in the thin tunnel portion (small intestine). The journey isnt complete and the journey has already altered the shape of the car pretty significantly giving a rusty color. Once in the larger portion of the tunnel, the cars are checked for stray passengers and are hosed down a bit so that transition out of Point B isn't so bad. Sometimes, the train cars park juuust outside the gates of Point B so they can exit at the best time for the operator (toilet). Now, all of this goes fucking nuts when you load a bad set of train cars at Point A. The track sensors located everywhere along the track, detect this alien set of cars and sends a distress call to the Supervisor (your brain). The Supervisor wants to handle the situation without having to phone the Manager (your consciousness) about the craziness on the tracks and also wants to make sure you never know it was on the tracks. It has to make a choice now: send it back to Point A violently and somewhat painfully risking tearing the tracks, or send it to Point B as fast as fuck? Depending on where it's located on the track, it'll choose the best route. Let's use the destination Point B. The Supervisor hits the panic button and puts all the train cars that are on the track (in your body) on overdrive. The tunnels are flooded with water and lubricant to speed all the cars up and get them the hell out of there as quickly as possible. Cars collide with each other, and previously well formed cars are just flooded with water and lubricant that they are just a soggy, shadowy reminder of their former glory state. The Media (pain) hears about the car collisions immediately begins filming live the high speed, flooded train cars out of control. They want to knos how an alien set of train cars were put on the tracks and they want someone to pay for such carelessness. The Manager is just watching the horror unfold on Live TV but cannot do anything to stop it, because the Supervisor was deaf and he had not installed a means of communicating with him after hours in the office. I hope this answers your question. TL;DR when you get diarrhea, everything gets pushed out, one way or another. There are no passing lanes. Source: medical student Edit: Wow, thanks for the gold!!\"",
"Am I the only one who is quite certain it takes me less than two days to poop out something I've eaten?",
"It's called the gastrocolic reflex. Expansion and irritation of your stomach leads to the activation of your enteric nervous system, which is a network of nerves running all throughout your GI tract. This activation leads to peristalsis and movement of the colon to make space for the new \"to be digested\" food. It takes hours to make stool from your food, it never runs right through you. Certain irritable foods can make your enteric nervous system get a little testy, so that's why that Indian curry seemed to come straight out. URL_0 Edit: In the hopes of sparing my inbox some grief, let me explain. The fact is there are many reasons why eating can trigger defecation and OP's question is non-specific. I still think my answer is the most common reason as OP didn't mention anything about diarrhea or corn or contaminated food. Other mechanisms are also valid and have been well covered in other responses. Also spelling.",
"I recently have lost my gallbladder and can say, with quite large amounts of certainty due to certain seeds and grains, that I can poop out foods I have eaten just hours after the act.",
"Ooh! I know this one! When food exits your stomach to enter the intestines, it's blocked by a valve called the pyloric valve to keep you from overloading your intestines with too much volume. Your body, wanting as much nutrition as possible because it doesn't know you plan on eating again, will hold as much food in your large intestine as possible for as long as possible because the longer it's in there, the more nutrients are absorbed. So, when you eat and the pyloric valve is opened, that is a signal to your large intestine that \"hey! We have food again! Get rid of that old shit (pun intended.)\" This caused your colon to contract and poop out what, at this point, may be day or two old poop.",
"Your stomach/intestines clear themselves out so that they can better process the food you just ate. It basically puts your digestive tract on overdrive.",
"To add on to what others have said, besides emptying you as a measure to ensure the bad food gets out, certain foods like coffee will stimulate your rectum into wanting to release despite not even being past the stomach yet",
"Hey! My post from way back when! Thanks for linking it. If you need more clarification, I can try and come up with something more descriptive. I'm in residency now and still haven't had a five year old (actual age) ask me about diarrhea because this is how I would phrase it (without the curse words of course).",
"I thought it took an average of around 9 hours give or take. And what happens when you go sooner is generally when you change it up from your normal diet to something you're not used to digesting",
"Two days? I ate corn with dinner last night and saw it in the toilet this morning.",
"As someone with IBS, I've had very.. recognisable.. food rush out in as little as 6 hours. If your body wants it out, it gets out. It's not always the case, if I manage what I eat well, I can go 24+ hours before it comes out. But any food that I know causes problems, out everything comes.",
"Follow up question, would it be possible to clock how fast the waste goes through the intestines. In say miles per hour?",
"This is a post I read a while ago that I loved and I thought explained the process of \"gotta go\" in a super interesting way: URL_0",
"Where did you hear it takes two days to poop out what you eat, it doesn't take near that long and sound unhealthy and unsafe?",
"[Here's a guilded ELI5 answer]( URL_0 ) by /u/jiggity_gee from last time a similar question was asked. His answer is presented with a train anecdote.",
"The food/drink can contain elements that stimulate cholinergic receptors, directly tied to your GI tract. Caffeine for example. Brainiacs, correct me if I'm wrong.",
"More importantly: could you eat so gradually that you produce an eternal, unbroken turd?"
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5oucd6 | Why do people still think the earth is flat? | Other | explainlikeimfive | {
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"People don't think the Earth is flat. OK, if you want more details, almost nobody thinks the Earth is flat. There are some people who say they think the Earth is flat, but it's mostly just a cry for attention, like when a little kid says he's going to hold his breath until he dies."
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5oue1p | How do airlines outside of the United States provide such a great experience at a lower cost than those in the U.S.? | I flew on three different airlines in Southeast Asia for the first time the other week. They provided an actual meal, the attendants were extremely well dressed and mannered (almost like models - both men & women), and they put away everyones carry-on. The aircraft were new, equipped with comfortable seats plus movies/entertainment for short domestic flights. They charged on average $70 one-way. Meanwhile, in the U.S. I'm lucky if I get pretzels for $150 one-way when flying the same distance - yet they still go bankrupt? | Economics | explainlikeimfive | {
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"Chinese airlines receive massive subsidies from their government. This allows them to operate on lower revenue.",
"Many of the legacy US airlines are/where encumbered by self-funded pension programs that have a lot of retired former employees. More older employees who have earned raises, and therefore cost the airline more in payroll. Maybe the employees have better benefits. Legacy US airlines may also own older aircraft which are not as fuel efficient, or have higher maintenance costs. Foreign airlines, might have (younger) employees with lower pay and less benefits than their US counterparts. They may own newer aircraft which may be more fuel efficient or have lower maintenance costs. Maybe even lower taxes or subsidies from the nation.",
"No unions and lower wages plus there's actual competition amongst airlines. One airline can't buy up all its competitors like US airlines can because the competitors are often partially state owned.",
"There are a few reasons I can think of: 1. Many airlines in Middle East/Asia are *the official* airline of their host country, and receive some level of state support. Countries that want to break out of the \"developing/3rd world\" stigma use the airline as an extension of their global brand image. Hence their governments buy newer planes that sip fuel and are cheaper to maintain. 2. In keeping with (1), state support also means that domestic tickets may be subsidized. They may offset losses here with international tickets priced at a premium for the ultra-luxe experience they offer. 3. All aspects of flying a plane require *highly skilled* labor (including the flight attendants), and the cost of living is much cheaper in Southeast Asia than the US. As an example - an experienced pilot can earn well past $100k in the US. In China or Thailand you can afford the same standard of living on far less. 4. People in the US buy the cheapest ticket, and ignore most else. As a result, there's quite a lot of herd behavior amongst the airlines - if one airline gets away with charging a bag fee or eliminating snacks, others follow suit.",
"There are a number of reasons. First, labor is far cheaper in Asia than in the US. The cost of labor is about the same as the cost for fuel for airlines in the US, at around 30% of total airline costs. By contrast, it is usually around 15% for Asian airlines, with fuel being almost 40% of their costs. Second, many Asian airlines are state owned or heavily subsidized by the state. Those states recognize that bringing in people to spend money in their country benefits them. By contrast, airlines in the US are (mostly) privately owned and only benefit by taking you from place to place. Once you step off the plane, they don't get more money out of you until you get back on. Third, the people who fly on Asian airlines tend to be upper class citizens. A far smaller percentage of their population might fly somewhere, and those that do fly tend to be from the upper end of the classes. By contrast, people from a larger variety of the socioeconomic spectrum fly in the US. As such, the Asian airlines are dealing with different expectations of their customers (much like the US airlines did in the 1950s).",
"Many countries in that region need tourism for their economy, so providing the best possible experience and best deals for travelers is in their best interest."
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5ouf5b | Why are babies seemingly unfazed by vomiting as compared to someone older? | Even without a stomach ache to bring it on, most people freak out at least a little when they vomit, but babies just puke without warning and act like it never happened. Why do they not respond to throwing up? Bonus question, is their stomach acid not strong enough yet to bring about that stingy feeling after vomiting, or is it something to with baby food? | Biology | explainlikeimfive | {
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"Babys do not yet possess the mental capacity to \"save all data\". They forget things that aren't to bad pretty fast. The same with little children. They stumble, fall, cry and 20 seconds later have forgotten they fell in the first place. For a baby its *puke, wonder what was that, forget what happened, drool*",
"to a baby, everything is unexpected. When you put your hands in front of your face, they are surprised to see your face when you pull them away. If everything is a surprise, then nothing is. Puking wont phase them any more than anything else would."
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5ouka1 | Why does room temperature not feel very cold to our bodies? | If our body temperature is ~98^^o F , then why does the average room remperature of ~70^^o F not feel cold to us? | Biology | explainlikeimfive | {
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"Humans are mammals, which means that we're warm blooded; our bodies constantly generate heat. We have to lose all of that heat to the environment at roughly the same rate that we produce it, or we'll overheat and die. In > 98°F weather, we can't lose heat normally, because heat can't transfer from a cooler substance (our body) to a warmer substance (the air). So we start overheating slightly, and we have to use evaporative cooling via sweating in order to shed excess heat. But at room temperature, the air is cool enough to absorb our body heat as quickly as we create it, so our body remains comfortably at the same internal temperature.",
"Air is pretty bad at taking heat away from you. It's a similar reason to why water feels colder than air even if they are at the same temperature. Water is great at sucking in a large amount of heat."
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5oukwi | What is the difference between a director's cut and an unrated cut? | Other | explainlikeimfive | {
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"When a movie is made a committee decides what rating it gets, if it cuts certain things it may get a lighter rating. Depending on the movie/director's vision/production company, they may be aiming for a certain rating to get a different and/or bigger demographic. So for instance, if I make a slasher movie, and too much blood will give it an R rating, but I want to sell it to angsty teenagers, I'll cut out the blood. Now if I want to make a little extra cash, I'll make a DVD cut with the bloody bits that didn't make it into the final movie to sell to angsty adults AND teenagers AND people who want to see more blood or thought a PG13 rating didn't do the movie justice. This is an unrated cut. A director's cut is similar, but this time the cuts are not strictly speaking to lower the rating. When a movie is made it needs to fit a certain time slot depending on how the producers want the movie to be marketed. A 3.5 hour long movie won't sell as many tickets as a 2.5 hour one. So nonessential, and occasionally essential, scenes will be cut to shorten it. Despite this, a director still has a specific vision for their movie, so a director's cut is sold with all the little bits that were cut out. This is usually marketed to the diehard fans, but lately it's also marketed as making bad movies better b/c essential scenes are being cut more and more frequently in favor of shortening a movie (see SvB). TL;DR: An unrated cut puts back in scenes that were taken out to lower the rating, a director's cut puts back scenes that were taken out to shorten the length of a movie."
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5oull9 | How does the Metal Grate on a Microwave Oven Keep all of the Microwaves in? | Physics | explainlikeimfive | {
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"Electromagnetic waves can't get through gaps in grounded metal that are smaller than half of their wavelength. The frequency of the microwaves in most microwave ovens is around 2.45GHz, so their wavelength is ~12.24cm, which means those waves get blocked by gaps in the mesh smaller than ~6.12cm. The actual gaps on a microwave door are usually a lot smaller than that, because you *can* cause higher-frequency / smaller-wavelength waves to come out of the microwave if you put something conductive, like a fork or metal foil, inside... the visible arcing that results can have wavelengths across the spectrum. Those waves wouldn't do much damage to you, but they might cause problems for other nearby electronics, and they might violate legal certifications regarding well-behaved electronics (such as the FCC Class B designation most consumer electronics are required to meet in the US). Visible light has wavelengths in the 390nm-700nm range, so it has no problem getting through the gaps even if they are very small. The waves in a microwave oven are only 'micro' in comparison to radio/TV waves, such as the VHF channels transmitted on wavelengths in the 1-10m range."
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5oumxi | The French Foreign Legion and the Siege of Jadotville | I just recently finished watching The Siege of Jadotville. I found the context interesting and wanted to do research on the actual events and story. I came cross a man named Roger (René) Faulques whom fought AGAINST the UN and Irish soldiers as a mercenary. Now I learnt France honoured him for his actions while at the same time he attempted to kill UN soldiers. How could the french allow for this and does this happen still? The Siege of Jadotville happened in 1965. | Other | explainlikeimfive | {
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"So, let me begin by dispelling the common notion that UN resolutions carry some sort of weight of law. They do not. There is no law in international politics. Countries can and frequently do ignore UN resolutions when they feel those resolutions are in the slightest bit inconvenient. Rather than viewing a UN resolution as law, its more accurate to view it as a sort of general proclamation of how the international community feels on a subject. UN Security Council resolutions are no different, but they are backed by the fact that the five permanent members (the US, Russia/Soviet Union, China, UK, and France) have to all agree to them. But that does not mean that those five members always *actually agree* with every security council resolution. Sometimes they don't agree with those resolutions but allow them to go through because they have been paid to do so, or blocking a resolution would look bad. France's vote on the Security Council resolution that authorized UN forces in the Belgian Congo was one of those instances. When you hear about the Cold War you frequently hear about it being a conflict between the US and Soviet Union, but that isn't correct. The Cold War was actually three different conflicts, of which the US-Soviet was the most prominent. But there were two others - the Soviet-Chinese conflict which is irrelevant here, and the France-Everyone Else conflict which is. Throughout the Cold War France continually sold itself to countries in the third world as a viable partner in opposition to either the US or Soviet Union. They weren't particularly successful in this, but did manage to form a loose coalition in which Iraq, Libya, and some West African countries were \"allied\" with France against both the US and Soviet Union. One of those \"countries\" was Katanga, which was a breakaway state from the Belgian Congo. The Belgian Congo was a Belgian colony until 1960 and France felt that this status made it a part of the French sphere of influence. But when it gained independence the Belgian Congo completely severed its ties with Europe and eventually came under the control of Mobuto Sese Seko, who was a strong US ally and virulent anti-European. The UN Peacekeeping force came about as a result of some weird Cold War politicking in which the country descended into civil war immediately upon gaining independence and the Soviet Union, which thought that a post-independence government would support it, threatened to send troops to the country unless a UN Peacekeeping force was sent to stabilize the country. The French didn't want the peacekeepers there because they wanted to support to rebels and overthrow the new government. But at the same time they couldn't veto the resolution because doing so would have caused the Soviet's to intervene. But as I said, the French did not want the UN Peacekeepers there - they wanted to get rid of the anti-European, pro US post independence government and replace it with a pro France government. In furtherance of that position the French began to clandestinely support the Katanga rebellion. As part of their support, they authorized members of their military to go on \"leave\" in order to become paid mercenaries for the rebellion. Roger Faulques was one of those French military servicemen. The French honored him for his actions in that battle because he had either been ordered to be there, or had gone there as part of a volunteer force in support of official French policy."
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5ouojn | What causes the reaction our faces have when we eat sour things like lemons? | Chemistry | explainlikeimfive | {
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"Because it's an automatic 'disgust' response. Expressions are very helpful when eating, as it enables others around you to see what you're eating, and then avoid it if you look disgusted/revolted/etc. Edit: It's an evolutionary trait - if you study other primates in the wild, they do the same thing.",
"If I remember correctly, it is the salvic system in your mouth cramping up from being in over drive mode."
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5ous72 | What really happens when bread, cookies, chips, and other similar foods go "stale"? | Other | explainlikeimfive | {
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"text": [
"It has to do with changes in the structure of the molecules that give the food its usual texture, but the specifics vary depending on the type of food in question and what it's made of. With foods that are normally moist and pliable/chewy (bread, cake, some cookies, etc.), the starches (long chains of sugars) that make them up spread out when cooked and link together, forming a sort of flexible mesh that's responsible for its texture. As the moisture from the environment begins to evaporate, the starches begin to crystallize, making them and the overall structure much more rigid, so it loses its pliability. It's essentially the same process as what happens with jello: when it has lots of moisture trapped inside of it, the overall structure is relatively pliable, but when you decrease the moisture, it becomes more rigid and brittle. Similarly, if you add heat to stale bread, it will help to recoup some of its chewiness and original texture (a bit of moisture helps with this too). Try microwaving a sale dinner roll for a few seconds (with a damp paper towel, ideally) and see for yourself. It's the same idea as remelting jello by exposing it to heat (and maybe some water) and letting its structure reform. Now with foods that are normally crispy (chips, croutons, breading, etc.), it's kind of the opposite: you want them to be dry and have a rigid molecular structure, so adding heat and/or moisture will cause their structure to become more pliable and chewy in texture."
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5ov74y | Why do we pay hundreds and hundreds of billions per year on military actions and upkeep, but the argument against paying for public healthcare or higher education is 'wait times' and 'earning it.' | Economics | explainlikeimfive | {
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"First, I want to say the arguments I'm about to make are ones I personally strongly disagree with so I may not support them as well as a true believer. The essential question is \"what is the purpose of government?\". For some, they believe that government's main goal is safety. The government's job is to prevent other armies from invading you, from criminals from killing you and that's about it. Anything else the governemt would do would be to both encroach on freedoms and to push hard on the private sector damaging it. So, ,in effect the only thing governments should spend money on is the military. And if you have the best military, then you have the best government because that's government's purpose. The argument towards freedom is that any time the government enters into an area to spend it must in some way regulate it. That means new ways the governemt creates rules to interfere with people going about their daily life. Sure if the governemt could get involve with higher education, but then you'd have to deal with the governemt deciding what is appropriate higher education or the appropriate hoops you need to jump through. The people who believe in this argument point to the aggressively expanding administrative state in the modern era. They look at environmental regulations that have caused absurd beuracratic moments like having smaller farmers ditches that fill up with rain water regulated like large scale industrial farming irrigation systems. The last piece of the argument is an essentially capitalist one. They see that the government spending money crowds out or distorts a market. Because the government can spend so much it changes the value of things and might suddenly make a completely useless widget successful because the government says it should be. These people believe that only the action of private citizens should create value. Thus, they don't want things successful without reason. But doesn't that apply to the military, you might ask. Well no, because the only appropriate purpose of the government is protection from criminals or military. So there, it doesn't matter what the government spends because that's what a government should do. Edits: A few quick spelling changes. Apparently, I wrote government \"governmetn\" a bunch...",
"The military has to be provided on a shared basis. It is not realistic to say to your neighbor \"Stop being greedy, pay for your own navy!\" But it's much more realistic to say \"Pay for your own healthcare\" or \"Pay for your own education.\""
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5ov8pb | I've heard you can't "catch up" on lost sleep. Does this mean I'm going to keep adding to the mountain of exhaustion that is my life until my dying day? | Biology | explainlikeimfive | {
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"dcmcmgk",
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"text": [
"Not quite. If you simplify and say that our body needs 8 hours of sleep for every 16 hours awake. If you miss out on some of that sleep then you may have some symptoms, one of them being exhausted. If you finally get a full 8 hours of sleep most of your symptoms go away. There may be some health affects still remaining but for the most part you are good to go. It is similar to how you need a regular oil change in your car. If you skip an oil change you may have issues with your car like overheating and lower performance. However those go away once you finally do an oil change. But there will have been some extra wear on your engine and doing two oil changes back to back will not do any good.",
"I mean, yeah, if you keep depriving your body of quality sleep. While you can't \"catch up on sleep\" by sleeping in a couple of times or taking a nap here or there, you can get back to your normal circadian rhythm (your natural sleep/awake cycle) by just going to bed a bit earlier than usual and waking up at your normal time. Your goal is 7 to 9 hours of good sleep, in a dark and quiet room. You might need melatonin to jump start you for the first couple of days/weeks, but eventually your body should start to regulate itself again. Sleep is the most important thing. Don't skimp on it."
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5ovbsl | How is it that cannabis has so many different 'strains' which change the appearance and other characteristics of a particular plant? Do other plants share similar significant genetic variations? | There are countless strains-all with different looks, smells, tastes, colours and other variations. Obviously there are other things in nature that are produced with differing characteristics-red/green apples for instance, or green/purple grapes. Is cannabis unique in how easy it is to 'combine' strains and genetics to produce particular characteristics? Are there any other plants that share this feature? | Biology | explainlikeimfive | {
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"Cannabis have been cultivated for many different uses over the years which have resulted in a lot of genetic variation. This is not unusual with cultivated plants. Take for instance the mustard plant which not only is prominent in the spices section in the grocery store but also consists of about half the vegetable isle with variants such as the cauliflower, broccoli, turnip, cabbage, canola, etc.",
"Variability in the genes of different members of the same species is extremely common of life in general; it's the norm. And that's a benefit since it allows for adaptation if their environment changes which in turn helps ensure the survival of the species as a whole. For example, if some disease came along and everyone was susceptible to it, the entire species could die out^1, but if there's some variability in the immune system of different individuals, some of them might survive and be able to repopulate. Thankfully in nature, it's rare to find a species or population that doesn't have significant variation among its members in at least some of its genes. When there is little to no variability, it's pretty much always caused by inbreeding and/or human intervention. As long as agriculture has existed, humans have been doing this with plants and animals in order to make them more suitable for cultivation, pets and livestock (i.e. to produce more food, make them more docile, resist certain germs/chemicals/diseases, stay ripe longer, have less or no seeds, taste better, etc.). Literally everything we eat is a GMO even though in many cases, this was done unknowingly (long before genetics and science in general were a thing). This process is done by taking your the best individuals of a species, breeding/crossing them together, and from their offspring, choosing the two best for further rounds of mating and repeating the selection process with each successive generation until the characteristics you're selecting for are consistently obtained. In the case of many cultivated plants, this has been going on for thousands of years and so the cultivated plants and their natural counterparts as may appear completely unrelated. Though great in many aspects, it does come with potential issues (disease susceptibility, birth defects, genetic disorders, etc.)^2 In any case, with marijuana plants it's basically the same process. Cross two strains together, select for the offspring that have the properties you're looking for (e.g., that they produce more fruit/buds, grow faster/better, have certain concentrations of different substances in them, etc.), and repeat until you get the result you're after. After that, make clippings, graft, grow, harvest and enjoy. ------------------------- Marginally-related tangents: ^(1. Something like that happened to the strain of banana that used to be grown as food. Eventually it was wiped out entirely by some sort of fungal infection. If you've ever wondered why banana-flavored candy tastes nothing like real bananas it's because the artificial flavor that's used was created to mimic the flavor of those now-extinct bananas. A similar fungal infection is currently spreading through the strain of bananas we're used to today. And even worse, it's not like they can take banana seeds and grow them from scratch; as you may have noticed, the strains we cultivate were engineered to be seedless. Because of that, they need to be preserved by making clippings of one strain and grafting them onto the stems and root systems of another (like grafting skin onto a burn victim or organ transplantation, more or less.)^) ^(2. For example, there were originally only four citrus fruits (citron, pummelo, mandarine, and papeda)^, ^(but from cross-breeding them together and selecting for different features, there are now many different strains/species of citrus fruits today. Fruits like oranges, limes and lemons never existed in nature before people began cultivating them. Another example is the various varieties of apples there are; originally, apples are what we'd refer to as crab apples, which aren't very nice to eat.)",
"*Cannabis sativa* is literally a noob in that. check out the variability of [*Brassica oleracea*]( URL_0 ) which is one of the Boss in that. you may have eaten it as a cabbage, brussel sprouts, cauliflower, broccoli... different varieties but same species, with waaaay much more differences than Cannabis varieties."
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5ovgid | What stops pharmaceutical companies from slightly tweaking competitors medicines and selling them as their own? | My thinking comes from legal highs in the UK and their initial legality due to mimicking a banned substance but tweaking chemical compounds so its technically a different drug. | Chemistry | explainlikeimfive | {
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"text": [
"Patent protection often extends to what are called biosimilars. As the name implies, these are tweaked versions of the same drugs. URL_0"
],
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5ovqnm | What is preventing blue states from enacting single-payer/universal healthcare? | Other | explainlikeimfive | {
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"Most US states have constitutions that would permit this, or at least have a mechanism for amending their state constitution to permit this. What's preventing it is lack of desire to raise taxes or regulations in just one state, because that might drive businesses or wealthy individuals to move to an adjacent state. By contrast, if *all* states do something, that risk is lower.",
"The federal tax code, and other states. First, single payer would require the state to raise a significant amount in taxes. On the flip side, you and your employer wouldn't have to pay insurance premiums. *However*, employers do get a federal tax break for their share of those premiums, so the benefit of not paying those premiums is offset by increased federal taxes. The ACA did not give individuals or employers any favorable breaks if their state implemented universal healthcare. Second, people and businesses (especially big corporations) are mobile. Many people live in one state and work in another, especially in the Northeast. The burden of increased taxes could cause individuals and businesses to leave the state. This is especially true for Vermont, which [tried and failed to implement single payer]( URL_0 ).",
"Insurance works because a bunch of healthy people won't use it at all, and the insurance uses the profit they obtain from them to pay for the expensive costs of treating their terminally ill customers. It only works if there are way more people putting in than taking out, and if there are more healthy people than sick people. If blue states did enact their own form of Universal Healthcare the premiums that the working healthy citizens would have to pay would skyrocket as more and more chronically ill patients moved to blue states to seize on the opportunity.",
"The same thing that prevents Democrats from even talking about it: *they don't want to.* I wouldn't be surprised if it was related to the health lobby. Their reach is strong."
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5ovwqy | Why are so many invasive species in the US waterways from China? | Other | explainlikeimfive | {
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"text": [
"Ships take on water and sand as ballast (necessary to balance the ship) and this can lead to illegal dumping or accidental leaks of said ballast. If this water or wet sand contains animals, you've just introduced a foreign species.",
"Most of them are not actually from China. They may happen to exist in China, but they may just as well be brought over from other places in Asia. Besides, looking at a [list of invasive aquatic species in North America]( URL_0 ), I can see plenty of aquatic animals which are not even from Asia. Plenty are from Europe, Australia, South America and even different regions of North America."
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5ow5pf | Why does eating a lot of sugar makes you sleepy? Shouldn't it be the opposite as sugar provides you energy? | Biology | explainlikeimfive | {
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"text": [
"Both are true. First the sugar provides you with energy. Then when it's used up you \"crash,\" that is, you experience a sudden loss of energy (due partly to the excessive insulin your body put out to process all that sugar). That's why nutritionists recommend other foods that provide a more continuous supply of energy over a longer time. You don't get the \"boom\" but you avoid the \"crash\" after."
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5owgop | How do some people with Dissociative Identity Disorder exhibit abilities while in some personas that there real self can't do? | I was reading about the case of Billy Milligan, who had Dissociative Identity Disorder and had 24 documented personalities: URL_0 One of these personalities could write and speak in Serbian and was extraordinarily strong. The page doesn't say that Billy, in his normal persona, could speak in Serbian. How is this possible? And how could one of his personas be far stronger than another? | Chemistry | explainlikeimfive | {
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"As for how, the general consensus is that he learned at least some of the language somewhere, and that it took off from there. There are multiple cases dealing with brain injuries that deal with complete changes in personality and sometimes complete changes in language, so an alter ( alternative personality) knowing a different language isn't completely impossible. How Regan knew Serbian while Billy didn't? It's the same as why you might know English better than someone else. Regan is technically a completely different person. So he may think and speak in Serbian as his first language and English had secondary. You have to understand that the question isn't really why Billy can speak Serbian, it's where did Regan learn Serbian from. It wouldn't have to be a lot, just enough for Billy's brain to learn more. Example: You know the French word for dog and door. You see a dog walk through a doorway. Someone says in French \"the dog walked through the door\", you can figure out which word means \"walked\". Now you know the French word for \"walked\". The brain is capable of amazing things. Absorbing a language isn't that hard for a brain wired to do so. That's why there are some people who can learn and speak in multiple languages easily, while someone else under the same circumstances, with the same opportunities, may not be able to learn a second language to save their life. Once the Regan personality fully developed he probably just went and interacted with Serbian people and media, which expanded his vocabulary. As to how he can be stronger while still only possessing the qualities of Billy's body, that deals with Regan's mindset. Have you ever seen people psych themselves up before lifting a heavy weight? Or someone else is yelling at them to \"get mad at it\"? People tend to exert more force when they're angry, even if you discount adrenaline as a factor. People tend to be stronger than they know, but without proper motivation or the proper mind set, they don't exert their full capability. With Regan being the angriest personality (he was referred to as the \"keeper of hate\") he would be more likely to put more effort behind something than Billy would. Therefore he'd be utilizing more of their body's capability (basically putting more \"umph\" into it) than Billy would. In other cases, it comes down to the simple fact that the brain is the epicenter of DPD, and the brain tells everything else what to do. It could simply be that Billy's brain is convincing his personality that he's weak. He goes to pick up something, and he can't because his brain tells his muscles that they can't handle the weight, while it tells Regan's personality that they can. When dealing with the traits of different personalities, outside of obvious answers, you start getting into unsolved neuroscience. Unlocking the brains full potential. If someone could figure out and reproduce how Regan learned Serbian without Billy really trying, they could make a whole lot of money selling that ability to people. There are cases of a personality having a disease that the others didn't. Why? Because no matter what condition your liver/kidneys/lungs/whatever are in, if your brain convinces them that they're not working, then they'll stop working. EDIT: more information",
"When you talk about DID, it's important to remember that **there is no objective, empirical way to measure or evaluate claims of DID**. In fact, there isn't even a universally accepted definition of the disorder. There is no measurable biological information that one would expect to observe with imaging like fMRI. It's just...what someone says is happening to them. The leading theory is that trauma or stress causes dissociation and you \"forget\" about connections, which allows you to create separate identities. Say you have three groups of traits. Normally, you see yourself as the whole of the three. It's theorized that some people who dissociate lose whatever ties bind those that group together, leaving three separate groups of traits that appear as three separate identities. But **there is no study that has ever demonstrated this mechanism**. Another theory is that alter identities are actually hallucinations, and one is experiencing psychosis not DID. Now, dissociation as derealizing or depersonalization are well-studied reactions to stress, anxiety, trauma, etc. But they don't make people forget who they are. With the Billy Milligan case specific, not criminally responsible is a *legal opinion*, not a medical diagnosis."
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5owh91 | If a soldier is captured, does that count as overtime? | Other | explainlikeimfive | {
"a_id": [
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"text": [
"Soldiers are on the clock 24/7 365.25 days a year and don't make over time. Sure we get to go home, but if a war suddenly starts, we move. If the war lasts 5 years where we don't go home, that sucks but it's what we do."
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5owj4l | What would happen if everyone on a plane didn't switch their phone to flight mode | Technology | explainlikeimfive | {
"a_id": [
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"text": [
"Most likely? Nothing. The flight would proceed as normally, with no real notable incident. But potentially? If the chance of catastrophic failure is increased by .1% ... is that really worth not switching your phone to airplane mode? It's not like you'll have service at 30,000 feet, and to be honest... why gamble?"
],
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5owl29 | Why is the Python language so heavily divided between two versions (2 and 3)? | Technology | explainlikeimfive | {
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"text": [
"Python was already really popular when version 3 came out. Version 3 had a lot of non-backward-compatible changes which broke most version 2 code. A lot of Python projects aren't just one guy's Python code, they combine lots of people's Python projects together. If you maintain a Python 2 project, you can't move that project to Python 3 until you do some work re-writing your own code, *and* the maintainers of all the projects your project depends on also do similar work re-writing their own code. Much Python code is written and maintained by volunteers, or written and maintained by people working for companies in the course of their jobs. The thing is in the first case, as /u/gr33n3r2 points out, the work is tedious, time-consuming and un-glamorous. Most volunteers are more excited by, and thus more likely to spend time working on, writing new code and adding new features to existing code. For people who publish code as part of their job, often the code's a by-product of writing some product like maybe a website. The thing is it's easy to justify to your boss writing some software that doesn't exist and needs to exist in order to build the website your company wants to create. And it's not that hard to convince the higher-ups to let you put it out there so other people can use it, it's not a competitive advantage because it's so far removed from the things that actually make your company money, it adds to your company's reputation among technically savvy people who recognize good computer code when they see it so it's effectively a recruiting tool for your IT department, maybe some of those open source volunteers will contribute features or bugfixes to the public code that improve your website without costing you a dime, maybe allowing you to publish it under your own name and enhance your own reputation is critical to your employee morale and makes you less likely to demand a raise or leave the company, etc. When the website already exists and runs perfectly in Python 2, it's not so easy to justify to your boss that you should spend time re-writing the software that already exists and runs perfectly just so other people who use it can use Python 3, which your company doesn't use."
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5owmtt | Why does the US have such a large defense budget | Economics | explainlikeimfive | {
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"Well, the US don't have such a high defence budget comparatively as people think. On average the world have a military budget of 2.3% of their GDP. The US is higher than that at 3.3%, but we talk about a 40% increase over the world average. And on of his main adversary Russia have a military budget of 5.4% of their GDP. So the main reason why the US have such a high military budget is mostly because it's the richest country in the world. What explain the 40% increase over the world average is mostly because most country just need to defend thier own territory, while the US as a superpower have interest all over the world. I'll give you an exemple. The US is one of the few country that is able to take care of their citizen all around the world in case of crisis. In 2011 at the start of the Lybian Civil war, China had to ask the US to get their Citizen out of their because they didn't had the assets to do it fast enough. A US investor have more confidence to invest in other country when he know that US governement can back him and his employees if something go bad. That's a way to increase the economic reach of the country. Another reason is that the US is part of NATO, but that a lot of those country doesn't have a big enough military budget to accomplish their part in the defensive alliance and the US need to take the slack. The US have about 30 thousand soldier in Europe. The US also took responsability in South Korea and Japan, which became precious allies. The US have about 60 thousand solider in those two countries.",
"After WWII, most of the world's militaries were drained, and their economic potential had been bombed into rubble, for both allied and axis powers. Their people needed food and clothing, so spending money on factories for guns meant leaving someone starving and naked. The only first-world economic power with production capacity and the people to make it were in the US. Through international treaties and decades of cold war, the US military promised to protect countries where we held interests, which was pretty much everywhere. While it may feel like signing away soverignty to allow a foreign power to put a military base in your country, they do promise to respect and enforce your borders. This enables you to pour money into rebuilding and not defense. Fast forward to now and everyone's mostly rebuilt. However, the US has kept manufacturing guns and tech for two simultaneous world wars. We could presumably reduce our worldwide presence, but that means the countries we're currently protecting would seek protection elsewhere. Maybe they'll defend themselves, but that means they might start actually fighting each other again (see India/Pakistan). Maybe they'll ask Russia or China to move into our old base. Right now we're the military power everyone turns to when international relations get too heated, and that is really expensive. Usually we can talk it out, ~~bribe~~ use our economic might to influence both sides towards a compromise, and avoid an actual war. If we stop offering these services, national leaders will turn to others for support on \"their\" side of an issue, which may not be in line with US interests. Sure we'll be saving money on military, but maybe now Taiwan is taxing exports to the US at a higher rate, and sending goods virtually free to Russia in exchange for their protection against China. The merits of this debate is one we'll likely see in the next few years. This also ignores the domestic issues of reducing the military. Does the army need another 100 Abrams tanks? Not really, but the folks in Kentucky that make them really want them to. So do the folks that make Abrams bullets in Missouri, and the folks that make Abrams coffee cup holders in IL. The US military is made in the USA, with many plants manufacturing almost exclusively for the Defense Department. Shutting down the Abrams Tank program would be a huge savings for the national government, but the entire town of Bumfuck, KY owes their livelihoods to the Abrams Tank factory. To shut that down would turn the place into worse than Detroit overnight. Before they leave though, you can be sure the residents of Bumfuck would vote against their congressman, senator, and literally anyone else they could loosely connect to their economic apocalypse. Since virtually every congressman has their own Bumfuck in their district making Department of Defense parts, the real key to reducing military spending is to find someone willing to commit political suicide that also doesn't mind basically destroying an entire region's way of life.",
"\"Defense\" is only in the most naive sense the defense of home territory. It certainly encompasses the idea of retaining control of local territory but there are many interests which can seriously disrupt or damage a country which are abroad. For example let us look to Venezuela. They were sliding along just fine as a Banana Republic until the bottom fell out of oil prices, on which 50%+ of their GDP and 95% of their government budget rested. This market shift (caused by economic feuding between the US and Russia) absolutely wrecked their economy, resulted in massive unrest, and is pushing them into a formal dictatorship or popular revolt. That didn't happen because they couldn't defend their borders but because they didn't have control over their interests which included the global oil market. The United States of America is really big and very powerful economically. What this means is that there are interests all across the world which can greatly impact the stability of portions of the country; California for example has a GDP roughly equal to that of France, so even something that impacts one state can have huge effects. A US military that can defend US interests abroad is equally as important as the various heavy armor bases across the country in defending the US. If you understand this it becomes much more clear why the US is partnered with some otherwise undesirable countries. Saudi Arabia for example has horrible moral character... but they are *stable*. If we can buy oil from them and not worry about if we can get more next year then we don't really care about their slave labor or social rights.",
"US defense budget is around 3% of GDP. Pledged minimum to NATO is 2% (much of NATO fails to meet this pledge). We do not actually spend that much more of our budget than other nations, Russia for example spends 5% of their budget, but we do have a much larger total budget so we are able to get a lot more things with the percentage we do spend. URL_0",
"Because we end up defending the entire free world. There's a reason most allied militaries spend so little, it's because we do it for them. The United States Navy provides global security across oceanic shipping lanes, for instance, because you mentioned the supercarriers.",
"It is because of the world wars. Up until ww2 the US defense budget was quite meager. However during the war something happened - the US government enlisted the help of all the major industries to build guns, tanks, planes and ships for the war effort. This allowed people from industry to establish strong connections with people from government - and while the war lasted - this was a good thing allowing the US to produce enough material to whoop the Japanese Empire and help the Soviets beat the Nazis. But when the war ended - it became clear that this is now a problem - because now the industry people were using the positions and connections they established during the war to pressure the US government to keep spending on arms and weapons even though the war was over and they didn't really need most of them. Some would even go on to say that these people actually supported going to war (like Korea and Vietnam) just so that they could sell more weapons and stuff. US president Eisenhower famously warned the American people about this - but 60 years later it seems we can safely say his warning fell on deaf ears. TL;DR It's because of the military-industrial complex fusing into the US government during ww2 and the failure of all subsequent administrations to change that.",
"Better to have it and not need it, than to need it and not have it. Nobody wants to invade the country with 7000 nukes.",
"The Defense of Department is not only the largest employer in the US but it's also a key provider of R & D research. The scope of what the DoD does far exceeds just the military. Their logistics division alone is massive employee 26,000 employees. Here's a small list of what the DoD oversees: United States Department of the Army * United States Department of the Navy * United States Department of the Air Force * Defense Intelligence Agency * National Security Agency * National Geospatial-Intelligence Agency * National Reconnaissance Office * Defense Advanced Research Projects Agency * Defense Logistics Agency * Missile Defense Agency * Defense Threat Reduction Agency * Defense Security Service * Pentagon Force Protection Agency * Unified Combatant Commands * National Defense University * National War College"
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5ox11k | Why are fire animations, fogs and shadows in video games so demanding for graphic cards? | Technology | explainlikeimfive | {
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"Imagine your graphics card is a famed renaissance painter named Giancarlo Pasquali Uberti sitting in a room. In this room is a canvas, paint, and a pneumatic messaging tube like they have at bank drive-thrus. Giancarlo also has a brother named Cirino Pasquali Uberti that he works with. Cirino can't paint, but he's great with customers and runs their shop. Cirino's job is to take orders for paintings, then send messages to Giancarlo that tell him what to paint. He can't fit big messages in the tube, though, it's real small, so each message tells Giancarlo how to paint a single object. A message might be like \"Paint an apple 50cm from the left edge of the canvas, 20cm from the top\". Giancarlo is very fast, but it takes him longer to finish a painting if he has to paint lots of individual things (it wastes time writing a message, sending the message through the tube, opening it up, reading it), or if he has to paint a really big canvas. & nbsp; Now, Cirino and Giancarlo are pretty smart, and they've figured out some tricks to make paintings go faster. Cirino takes great notes while talking to customers, and knows how far away each object in the painting is supposed to be. This is known as its depth. While Cirino isn't a good painter, he's very organized, so he sorts the messages by depth, closest object to furthest, and throws away any objects that are hidden behind something else. The only messages he sends to Giancarlo are just those objects that will be seen in the painting. This is way faster! Giancaralo knows that it's in order, so he doesn't have to waste time painting things that overlap. Since it takes time to paint an area of the canvas (the bigger the area, the more time), this is very efficient. Giancarlo doesn't have to paint over the same spots on the canvas at all, he just paints every spot once. & nbsp; Then comes a job to paint a still life with a frosted glass vase in it. Cirino sorts everything, and realizes there's a problem. The glass vase is translucent, you can see through it, so it changes how stuff behind it looks since it isn't totally clear. No amount of sorting can fix this, and he eventually realizes that Giancarlo is going to have to paint over the same spot twice to get the right look (remember, he can only tell Giancarlo to paint one object at a time in his messages). The clever brothers think about this for a while, and come up with an idea. & nbsp; Their new plan is to work on the same painting twice. First, they do what they usually do, sort all the solid objects front-to-back, and only paint the ones that can be seen. Second, they sort all the see-through objects back-to-front and Giancarlo paints each one in order, still careful not to paint any that would be hidden behind a solid object. Sorting the see-through objects back-to-front makes sure they look right if two see-through objects overlap, like if you're looking at that frosted vase through a stained glass window. It wouldn't look right if they painted the vase in front of the window! The results look great, but it's a lot more work than just painting solid objects. & nbsp; Now, for just a single vase it's not so bad, but once you have a scene with lots of smoke, fog, shadows, etc, Giancarlo spends a lot of time going over and over and over spots he's already painted to build up these translucent layers. This slows things down, and it's a big reason why your GPU struggles with these sorts of effects.",
"It's really hard to ELI5 graphics algorithms, but I'll do my best to keep it simple. **TL;DR:** All those effects make the GPU do a bunch of work twice (or more) instead of once. Of the three special effects you list (fire, fog, and shadows), two of them are actually the same thing as far as a GPU is concerned: fire and fog are both examples of partially transparent objects, so I will group them together. The work a graphics card has to do to draw a scene can be broken roughly into two parts. The first part is the work it has to do for each 3D polygon (triangle) in the scene to determine which pixels that triangle covers. The second part is the work it has to do for each pixel to calculate the color and brightness of that pixel. **Transparent objects are demanding because they make the GPU process each pixel multiple times, multiplying the amount of work done in the per-pixel phase of rendering.** **Shadows are demanding because they make the GPU process each triangle multiple times, multiplying the amount of work done in the per-triangle phase of rendering.** Without transparent objects, there is exactly one surface visible at each point on the screen (disregarding anti-aliasing). Therefore the GPU only has to calculate light and color for each pixel once. With transparent objects like fire and fog you can see multiple layers at each point on the screen, so the GPU has to calculate light and color for each layer at each pixel, then blend them together. To draw shadows, the GPU has to draw the scene from the perspective of each light that casts shadows, just as if that light were actually another camera. It usually doesn't have to calculate any color from the light's perspective, but it still has to go through the process of drawing each triangle in the scene for every light. It turns out that many \"demanding\" effects in video games are slow because they multiply some part of the work of drawing a scene: Transparency: Multiplies per-pixel work in the areas covered by transparent things. Shadow Mapping: Multiplies per-triangle work (plus some extra work at each pixel). Anti-Aliasing: Multiplies per-pixel work at the edges of each triangle on screen. Global Illumination: Multiplies everything by everything else until your GPU catches on fire... If that all sounds confusing, that's because it is. I can try to clarify if anything about my wall of text is particularly unclear. Edit: I should mention that the problem of drawing pixels multiple times is called \"overdraw.\" Edit2: I should also mention that \"duplicate\" work was probably a poor choice of words. It's not redundant, it just has to process the same point multiple times instead of just once.",
"**TL;DR**: Accurately simulating any 3D scene is impossible in a computer game. About 10^19 photons hit every square metre of earth during a single 1/60th of a second frame, so obviously simulating even a tiny fraction of the photons in a normal video game scene is just intractable. But a lot of simple stuff can be simulated in a way that looks good enough without doing it accurately. Fire, fog, shadows, refractive glass, mirrors and all kinds of other effects are stuff that *don't* work in this simple way of rendering things, so require a more complicated simulation to make them look any good. More complicated means more work for your graphics card. So the question might rather be: *why are things like rendering a chair in a room with two small lamps and no windows easy for graphics cards?* Below I will try to answer both questions. **More info:** Traditional 3D rendering works backwards: you start at the virtual camera and, for each pixel you want to render, trace out a line until you hit an object - each line goes out at a slightly different angle for each pixel. You then look at the angle and distance from that object to every single light source in your scene and calculate how much light the object is receiving. Then, examine the material the artist gave that object and see how it reacts to light to determine what colour it is at that spot. You then draw that pixel that colour. (This is backwards because in reality, obviously, light travels *into* the camera, not out of it.) This requires you to trace lines to see what they hit exactly the same number of times as there are pixels in your image. For each pixel you also have to calculate distances and angles to exactly the number of lights in your scene, though games tend to use tricks to reduce this number (by making lights outside a certain distance not count, or by pre-calculating a lot of this information so some more can be skipped.) This is all quite doable and is represented in [this diagram]( URL_1 ). Now none of this allows you to render shadows: suppose you're calculating a certain pixel and calculating the distance and angle from the object in front of that pixel to the single light illuminating the scene. At no point do you check whether there's anything in the way which would prevent light from getting to that point. To do that you'd have to not just calculate the distance and angle, but trace another line to every light (the shadow ray in the diagram above) - that takes more calculations and makes it slower. Again there are tricks: you could say that only stationary objects and light sources can cast shadows, pre-calculate all that information and then you don't need to do it every frame in the game. But this of course doesn't look as good. Basically for the other things the answer comes down to the same thing: forcing the engine to trace more lines. Sometimes you're forced to trace lines from the light sources instead of from the camera - this is very wasteful as you have no idea which will end up hitting the camera (perhaps after bouncing off some objects); any that don't have no effect on the scene at all. You're forced to trace far too few to actually look good and hope you can smooth out the resulting mess to look decent. Other times, like with reflective surfaces, you have to trace the bounces off the objects. If you have two mirrors facing each other, you have to cut off the trace at some point, which will prevent the render taking an infinite length of time but result in a black spot in the mirror. How about fog? Basic fog is actually easy and used to be a way to make games run *faster* - when you worked out what colour a pixel should be by tracing out a line to the object in front of it, you'd also mix that colour with the fog colour according to how far the object is away from the viewer. Then at some far-away distance, all objects would be exactly the same colour, and you wouldn't have to do any further calculations. It could sometimes produce [weird effects]( URL_0 ) if the fog doesn't match up with the rest of the background. But real fog isn't like this - as light passes through it, it scatters, making things in fog look blurry. It's partially transparent, meaning you can see things on the other side, but also the fog at the same time. So suppose you run the above algorithm for fog: you trace out a line for a single pixel and discover the first thing it hits is a region of fog. You can't just colour that pixel according to the properties of fog, because then the fog would be opaque, so you have to first do the calculations for what is illuminating that little area of fog, and then continue calculating. A naïve approach would be to continue the line through the fog until it hits an opaque object, and mix the colour of the opaque object with the colour of the fog according to the distance of the line segment that passed through the fog, [like this]( URL_3 ). Already this is more complicated, but this is not a perfect simulation. As I said, fog scatters light: each photon that passes through can be randomly disturbed so that it goes off at another angle. Also, the single line you trace through the fog might pass through a region which is shadowed - [like in this photograph]( URL_2 ) and those patches should be darker than if you just treated every path through the fog of the same length the same. So what you really need to do is calculate the illumination at every single point through the fog, randomly make the line you're tracing bounce off somewhere else. Except you can't do it randomly because then each frame, and for each adjacent pixel, the angle would be different - you'd get a flickering mess of noise. Instead you want to simulate the fact that each pixel is the aggregate of billions of rays of light, and simulate that they're all bouncing at once! Of course, it's not possible to trace billions of lines for each pixel that hits fog, nor to calculate illumination at every point within it, so games use tricks, but to get the look correct, you still need to do a lot of extra calculation. If I may digress a little, the problem is that you can't treat things like fog as being *homogeneous.* For 3D that means you can't treat light going through it as having only two interactions: one at the beginning and one at the end. (In fact it would be better to just have one interaction!) The traditional approach to cheaply modelling transparent objects is to pretend that a ray of light passes into, say, a glass paperweight, changes angle once due to refraction, passes through the paperweight being continuously attenuated as it does so, exits out the other side and is refracted again. The ray of light does not change path inside the glass, it never encounters a bubble, trapped piece of dust or anything else. If you want to simulate this things that occur in a *heterogenous* transparent object, where interesting things may happen inside, you have to chop the object up into thousands of pieces small enough that you can't see them, and perform complex calculations as your ray of light passes through each tiny volume. This is a general problem in simulation: whenever you can't deal with something as being defined by a simple process inside it, a start and an end, things get hard. **Digression over:** Fire is like glowing fog, so it has a lot of the same problems, but it also represents something very hard: a light source with size. When you calculate the illumination of an object, it's much easier if you can pretend all the light from each source is coming from a single infinitely small point, rather than being spread over, say, the element of a lightbulb, or a fluorescent tube, or a whole fire. This is because to accurately simulate the illumination you'd need to act as if there were millions of tiny lights all over the surface of the object, and calculate how far and at what angle they were to the thing being lit up. Millions of lights means millions of calculations - which again is not possible, and again the tricks that can be used to fake it are still computationally expensive. But also if you want to simulate the way fire moves rather than just recording a video of it, that is a very difficult process. Again you are reduced to trying to simulate the fire as lots of tiny particles - but nowhere near as many particles as makes up a real fire. So you try to apply physical laws to the particles but they can't actually behave physically because they're too big or because information like the air currents in the environment is lacking. Usually people just use a recording with some tricks to make it look less like a recording.",
"A lot depends on how all these elements are handled in a game. Best case scenario: - The fire is a simple object, animated in a 3d program and let loose in the game. The animation loops and it's quite noticable but you can get away with it. - The fog is just things in the distance getting blurrier. Looks quite bad but it's cheap. - Only static (non-moving) objects cast shadows, no dynamic lights. This might sound like a lot of assumptions but it's not entirely unrealistic and there certainly are games which can use this simple model. It's very, very cheap. Worst case: - Fire is made using multiple particle systems including multiple types of flame, randomized smoke, lights, dust and small elements flying around wildly. - The fog is also a large particle system with added blur effects - Multiple lights with multiple dynamic objects casting dynamic shadows This model is used in games with better graphics and there are multiple performance concerns. I won't go into the details but the main issue is that many of the effects require multiple passes which basically means the image you finally get on the screen needs to be drawn multiple times by the GPU. First object geometry, then lighting, then shadows, then particles, then special effects like antialiasing, bloom, ambient occlusion etc. and if you have a lot of those they can easily become a GPU bottleneck. Source: Make games. Tried to be ELI5 I know this is an oversimplification.",
"The shortest and simplest ELI5 I think is that, as in real life: - Fire generates light. - Fog blocks and alters light. - Shadows are cast by light from different sources. All these things either generate or alter light and dynamic light calculations are complex and grow exponentially with the amount of light sources and alteration sources present. the addition of 1 light source does not just add one light source or one more shadow to a scene, an additional light source interacts with the other light sources and every new light source or alteration in the available light alters the effects of every other light source or alteration in the available light. A really simplistic analogy on the scope of adding just one light source or alteration to light is this: Imagine counting to 9. You can do that in 9 counts and it'll take you under 10 seconds. Now add 1 more digit. Now you have to count to 99, which takes a lot longer, around 1 and a half minute. Now add another digit. Now you have to count to 999, which will take you around 17 minutes. Now another one. Now you have to count to 9999, which will take you over 2 and a half hours. And so on. Similar complexity exists in calculating the effects of light sources in 3D. In 3D Processing there are a ton of shortcuts and tricks to limit how large an impact a single light source has, but the effect will still be great with every one you add.",
"Just logic here but shit man compared to just still images there's alot going on image wise in fire and fog. It's more complicated so therefore it's harder to make",
"Short explanation. Turbulence is hard to model. That's why we can only predict weather a few days out. Fire and other \"random\" patterns take a lot of computation to look realistic",
"I feel like a lot of the answers on here are missing the \"like I'm 5\" part. As far as the animation of fog and fire they are represented by particles. Each particle makes a shape based on some behind the scenes math, but only one particle doesn't make for a convincing fire or fog. So the game has to create many particles with even more complex behind the scenes math to tell the particles which way to go, how long to live, the size and shape at birth and death, if it's colliding with other objects, how it can spread or if it can spread, is it making light or is it interacting with other light sources... So the computer has to keep track of all of that information for each one of the particles. The more realistic the fog or fire, the more particles, the more the computer has to keep track of. This leads to the shadows. One shadow is pretty easy. There is one source that sends light in a direction from it. When that light interacts with, say a character, it has to take in all of the shapes it hits on the character. The light draws a gradient from light to dark on each of the shapes it hits and then it also draws cast shadows. Those cast shadows on everything on the other side from the source. (source) < < Light < < {character} ~~cast shadow~~ [ground] Now that's relatively straight forward and doesn't take much power from the computer. That's why in a lot of fast paced games there is one global light that casts a fairly simple shadow under the characters. But, when you start adding more light sources in more cinematic games, with more objects interacting with it, with fog interacting with it, and fire with light making particles it compounds how much math the computer has to figure out to make everything look correct. Hope this was ELI5 enough. Sauce: Am animation director.",
"When the camera is looking at a solid object the computer only needs to calculate the color based on the most basic info- desired texture, ambient light, angle, etc. When the camera is looking at a translucent or transparent object (such as fire and fog) it needs to calculate this information for both the object you are looking through and the object behind it, as well as calculating how looking through one effects the other (opacity, refraction index, etc. ) each layer making it more complicated. Reflections have this effect too, as the computer effectively sends a line from the camera, calculates the effects of the object it hits (reflection, finish, color, opacity, angle of reflection) and adds to it the information for the object it lands on (when I was learning 3D modeling this was called Ray-Tracing). Again, the more objects the GPU has to consider, the more information it has to calculate, the slower it goes. Shadows use the ray-trace effect as well but the rays come from the light source and trace around objects.",
"It is about the number of things you see. The smog itself PLUS the things behind it. The shadow itself PLUS the ground, that is a mix between draw the ground, determine the direction of the shadow and the ground shadowing itself. Edit: this is a reason for Minecraft to be so heavy processing, lots of blocks and dropped items are visible at the same time, and each one has its own set of proprierties ready to be triggered. Walk by will make them emit walk noises, break them will take specific times. Er... oh, I think I lost myself a bit.",
"Everything a graphics card renders is a geometric shape. Each geometric shape, no matter how big or small, takes basically the same amount of power to render. The less like a geometric shape the thing is you're trying to render is, the more shapes you'll need to combine to make it. Organic-looking objects are the least geometric things. On top of that, if the items are not 100% solid, you'll need to render items behind it as well. Now let's say that the object generates its own light (like fire) or modifies the existing light as it passes through (like fog) and you're complicating things even more.",
"Fire and certain types of fog require transparency. In order to draw something that is transparent you need to draw the pixels behind it first. In order to make fire and fog look realistic you need to use multiple images which means the GPU has to redraw the same pixel multiple times. This is called overdraw."
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5ox18t | If electricity travels at 300k meters per second, why does it take several hours to charge some lithium ion batteries. | Physics | explainlikeimfive | {
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"A battery isn't simply 'storing electricity' the same way a glass stores water. The electricity that flows to a battery is used to reverse a chemical reaction. The electricity is converted into chemical potential energy. This is the part that takes some time. Since it isn't a 100% efficient process, excess heat is generated. If you were to charge the battery super quickly, bad things would happen. When the battery is being used to power something, the chemical potential energy is being converted back into electrical energy.",
"Electrons in a conductor don't travel nearly that fast. The velocity that the electrons themselves travel at is referred to as the [drift velocity]( URL_1 ), which is actually very slow (typically less than a millimetre per second). What travels quickly is the electrical *signal* - when a voltage is applied, the electrons at the far end of the conductor start moving almost instantly. You can imagine a pipe filled with water: * The velocity of the water doesn't tell you how long it's going to take to fill your tank - you would also need to know how big your pipe is. What you want to know is how *much* water is flowing, not how fast it's flowing. * When you start pumping water, the disturbance will propogate at the speed of sound in water (which is about 1.5km/s), but that doesn't mean the water itself is travelling that fast. The water that starts flowing out the end of the pipe when you turn on the pumps is water that was already sitting near the end of the pipe. The reason you can't supply a lithium battery with a higher current to make it charge faster is because doing so can damage the battery. Lithium batteries rely on a chemical reaction to store energy, which can only proceeed so fast. If too much current is supplied, lithium metal gets deposited on the electrodes, which results in loss of capacity as it is the lithium ions that store the charge. If this results in a short circuit, it can lead to thermal runaway and the [catastrophic failure of the battery]( URL_0 ). Lithium batteries must be used within specified voltage and temperature ranges in order to remain safe to use.",
"If you open the tap, water starts flowing out of it quickly. It still takes a while until your bathtub is full. 300 million meters per second, by the way.",
"Those two things aren't related. Electricity travels that fast. That's why when you flick on your lights, it's basically instant. But a lithium ion battery takes several hours to charge because it holds *a lot* of electricity. The issue isn't how fast electricity is traveling, but how much has to pile in before a battery is charged.",
"I bullet travels faster than the speed of sound, but you would still take hours to fill a house with bullets fired from your gun.",
"\"If light travels 300k meters per second, why does it take several days to get a tan?\""
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5ox2d7 | An atomic bomb can fit in a briefcase,yet diplomatic pouches are flown into countries without check.What then is nuclear deterrence about? | Other | explainlikeimfive | {
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"I'm not totally sure an atomic bomb can fit in a briefcase. The smallest nuclear weapons I'm aware of it the W54 and you would need a big back pack. It was about 10 inch by 15inch and weight about 50 pounds. I'm sure we can make a smaller one, but then you start to have problems shielding it. People will see that the guy is struggling to hold the briefcase with one hand (if that's even possible). And if the shielding is lower, then he guy will probably start to show sign of radiation poisoning at some point. Additionally, a nuclear bomb will emit radiation and those can be detected at airport.",
"A briefcase nuke is not very powerful, so you'd have to be pretty damn targeted to get any real impact. Regardless, is that really worth it? Let's say you get the best possible and managed to blow up the White House. The US has an entire suite of plans in place, the end result being **fire all the missiles**. Whatever country to insane enough to deploy a nuclear weapon on US soil is going to quickly find out what it feels like to be wiped off the face of the earth.",
"First: While nuclear bombs can fit in suitcases (larger ones, but still suitcases one can carry around) they are relatively small. If you as country just want to kill some enemy head of state, you can do so with other means. Killing presidents is relatively easy for a country that has a working nuclear program. Second: There are fission bombs and fusion bombs. Fission bombs are \"normal\" nuclear bombs, you can blow up a small city with it (measured in thousands of tons of TNT). Fusion bombs use fisson bombs as *igniter* for fusion and get a factor of 100 or 1000 more energy out of them (yes, mankind *did* invent a bomb where you need a device that can blow up a city as the puny igniter). Now, countries don't use \"small nukes carried by diplomats\" because there's nothing to gain from it. So what, the other president and his seat of government is gone? What now? That whole country and military apparatus is still in place! And oh, the Vice-President (or whoever down the chain of replacements) is now the new leader. What you might want to gain with nuclear bombs is *utterly* defeating another country and for that you need a few hundred hydrogen bombs, not half a dozen very small nukes carried by people. But in general it is even more simple: They are not checking diplomats because the countries know that the others do not want a nuclear war.",
"A briefcase can't shield the radioactive material required for a bomb. You don't have to open or search a briefcase to know if it has a nuclear bomb radiation detectors in airports would be going off like crazy if you tried to fly a bomb in.",
"(Not an expert but . . .) Diplomatic Pouches . . . aren't pouches. They're an international legal sticker affixed to something that makes that thing a \"Diplomatic Pouch\". I understood it to mean, if your government needed it, and was inclined to do so, they could slap a Diplomatic Pouch on a \"Container\" (like you see being hauled by a semi-tractor truck, or on a Container Ship . . .) and that large Container would now be a \"Diplomatic Pouch\". So you could fit a Massive well-shielded multi-warhead Nuke into a \"Diplomatic Pouch\". On the flip side, if Russia suddenly tried that, I would \"hope\" that we'd have the most sensitive radiation detectors known to man scanning it from the outside at the entry border, to try and determine if that's what's happening before it gets somewhere important. (Like near the Capital building during an Inauguration.)"
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