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The Syria conflict | Oh boy. Okay. Syria is (was, depends on how you see it) ruled by a dictator Assad (who is generally a dick). During a string of revolutions in arab world called the arab spring protests against his regime broke out. Western (USA, Europe) world usually supports the rebels when they rebel against a dictator (we don't believe in benevolent dictators). So the western world supported the rebels. Then the entire arab spring thing went to shitter because fundamentalist muslims took over. They started to do terrorist stuff and snuffed all hope for liberal reforms. Western world still supports some of the terrorists hoping they will calm down and because we don't really see difference between benevolent dictator and fascist islamic regime. Russia usually supports the dictator in a situation like this because they believe in benevolent dictators. Now more in detail about Syria. Protests against Assad (who is a dick) broke out. west supported protesters (believing they are not dicks). Assad used army against protesters (generally seen as a dick move). West supports protesters even more. some protesters become ISIS (bunch of dicks) and start establishing fascist dictatorship. West starts bombing them (we don't like fascist dictatorships). Some protesters become FSA (free syrian army). We support them because they have 'free' in the name and are generally seen as less of a dicks than ISIS and Assad. Russians support Assad because he is their ally and that makes him less of a dick to them. There are more rebel groups there (some are more dickish, some are less) but these two are the main ones. Russia and USA keep supporting their chosen side and turn this into regular proxy war. Brown people die in middle of the clusterfuck. | 288 | en |
why are loading bars and remaining times so inacurrate? | Let's say the progress bar is for loading a game level before playing it. There of course the copying of data into memory that takes the biggest amount of time but also things like unpacking compressed files, executing code to prepare the game session, maybe connect to an online server for a multiplayer session and download the names and characters of the other players. All these things are difficult to measure exactly: 1. Loading data from a hard drive or SSD becomes faster and slower depending on how efficient the data is located on the device and how bury the operating system is with other things. 2. Decompressing files is hard to predict unless you already know the content of it in advance but then why would you need to unpack it? 3. If there substantial code to be executed during "loading" (or better "preparation)" it's impossible to tell how long that will take. It's even impossible to reliable tell if will end at all. This is known as the Halting Problem in computer science, if you want to read more about it. 4. Anything involving networks is impossible to predict. Connection speeds may vary. The connection may get lost and the whole thing needs to be retried. All these things combined make it very difficult to give an exact estimate for the complete process and when one of the steps goes very quickly, that's when the bar "jumps" but when for example the networking part is super slow, that's when it's not moving for a long time. The same applies to other complex processes in software. Installing an application is similarly complex, even just copying files round depends on many factors so it can show this effect. | 288 | en |
How can nuclear fusion AND fission both work? | The core difference is that nuclear fission happens with very large atoms, and nuclear fusion happens with very small ones. This difference is all the difference when it comes to energy production. All nuclear reactions follow the same basic idea: energy is released if the total mass of the resultant particles is less than the mass of the initial reactants. Nuclear fission takes place when a large, somewhat unstable isotope (atoms with the same number of protons but different number of neutrons) is bombarded by high-speed particles, usually neutrons. These neutrons are accelerated and then slammed into the unstable isotope, causing it to fission, or break into smaller particles. During the process, a neutron is accelerated and strikes the target nucleus, which in the majority of nuclear power reactors today is Uranium-235. This splits the target nucleus and breaks it down into two smaller isotopes (the fission products), three high-speed neutrons, and a large amount of energy. This resulting energy is then used to heat water in nuclear reactors and ultimately produces electricity. The high-speed neutrons that are ejected become projectiles that initiate other fission reactions, or chain reactions. Nuclear fusion is what powers the sun. Atoms of Tritium and Deuterium (isotopes of hydrogen, Hydrogen-3 and Hydrogen-2, respectively) unite under extreme pressure and temperature to produce a neutron and a helium isotope. Along with this, an enormous amount of energy is released, which is several times the amount produced from fission. Fusion breaks down when the star develops an iron core because of the insane amounts of energy and force required to fuse iron atoms. Iron _can_ be used for fusion, but stars simply don't have the ability to generate pressure/temperature high enough to make that happen reliably. | 288 | en |
What are programming design patterns? | They are one of the reasons why some people drop out of CS programs in college, for one. On a slightly more serious note: a design pattern is basically a sort of recipe to solve a common problem -- only it's a partial recipe. These problems aren't anything "big" like "write an application to do my taxes", but they are small parts that occur in many different contexts. An easy example would be the `Publish/Subscribe` pattern. It describes how to be notified of a certain change or event. For instance, assume you're a chef. There's a cake in one oven, turkey in another oven, and a soufflé in a third oven. You don't want to walk around for an hour, constantly checking up on ("observing") each oven. No. Instead, you tell each oven to notify you when it's done cooking. While that's happening, you can go off and chop some vegetables or something. There are many ways to program something like this. But realizing that it's a common problem, and that there's a named design pattern for it, makes it easier to talk and reason about it. Kind of like two pastry chefs can talk about cake, without having to describe how to make a cake. They both have a pretty good idea of how a cake works. And because they both know about cake, they can say "this cake was really nice" or "it only took 20 minutes to make", or whatever the salient point is. It's a common misconception that you "have" to "use" design patterns, or that there is a magical list with "all" design patterns. The "gang of four" has famously published a bunch of them. But that's by no means all of them. | 288 | en |
What are Stocks | > What are they? Stocks are, in essence, equal portions of a company. When you buy a stock, you're buying a part of that company. If a company has 1,000,000 shares in existence and you buy 1 share, you own 1/1,000,000 of the company. Usually shares come with rights, such as voting rights, as well as the right to receive dividends, which are payments made to people who owns shares from the company. > Also, how do you invest in something that’s not yours? Well, once you buy shares, they are yours. It's exactly the same as when you buy something at the store. Once you buy it, you own it. > Why are they so valuable? If a company is really successful, it'll make a lot of money. This means the value of the company will go up because people will be willing to pay lots of money for shares in that company. Not all shares are valuable, though. They can go up and down in value. > What are stock brokers and traders? Stock brokers are the people who buy the shares on your behalf. You give them a call, ask them to buy X number of shares in XYZ company, and they do it for you in return for a small fee. The nature of brokers, however, is rapidly changing. Stock traders are people who buy and sell shares. Some buy them with a view to sell them soon afterwards for a profit, while others buy them and then hold onto them for years, maybe decades. > Is it easier to get into them then you think? I have no idea how easy you think it is, and am therefore unable to answer this question. | 288 | en |
If fire can't happen in space due to the lack of oxygen what happens if theres an explosion (what would it look like)? | Fire can and does happen in space. This is how rockets get things up into orbit, by burning huge, prolonged explosions in space. What *is* true is that a lot of things that we think of as combustable don't burn because they don't have oxygen to react with in space like they do inside our atmosphere. For fires in space, we have to bring along everything required to make the fire since we won't find any parts just lying around in any sizable quantity. Explosions are largely the same in space as they are inside the atmosphere. Most explosives include their own oxidizer to speed up the reaction, so they don't need atmospheric oxygen. The biggest differences are that the atmosphere provides part of the chemicals needed for the reaction (elemental oxygen), it is a nice medium to disperse combustable materials in to make a big fireball, and you get buoyancy effects where the heated gasses released from combustion tend to be pushed up (this is how hot air baloons work). This buoyancy ends up being important in another way. For a slow-burning fire in an oxygen atmosphere in microgravity (like that experienced on the International Space Station), a fire will burn and expand, but since it doesn't get pushed out of the way by oxygen-containing atmosphere, the reaction quickly runs out of oxygen and stops (presuming there isn't something else disrupting things). Also, oxygen isn't strictly required for making fire. You just need a sufficiently active heat-producing reaction that gives off gasses to make fire. It just happens that oxygen reactions very commonly do this and elemental oxygen in our atmosphere is *far* more common than other substances which might be used to make a non-oxygen fire. | 288 | en |
how does a TV remote control when a television turns on and off? | Aim your phone camera at it, specifically the shiny black part at the front. You'll see a purple dot glowing there. That's a very near infrared LED light. Just outside of human vision, but within the range of your camera. Purple because it causes the red and blue sensors on your camera to react. Not intentional or anything, but we just don't care about about this near IR light so let it do whatever. At least not with cheap cameras, good ones have a filter so this doesn't get in and slightly distort colours. If you don't see it on your phone camera, you have some fancy phone with an expensive camera that has this filter. Anyways, you'll note it flashes when you hit buttons. That's literally it. Just some Morse code (sort of, not literally the same patterns) flashes to your TV. A camera like sensor on your TV that is always on watches, and turns the rest of the TV on when it sees the right flashing code. A visible LED would work as well, but would annoy people with the flashing. This also explains why you don't need to point directly at the TV to make it work, but if you point the opposite way or completely block the remote it fails to work. It's not radio waves, doesn't go through things. It's more like a flashlight that just need enough of the beam to hit the TV. Also explains why you can bank it off a mirror or window while facing the wrong way. As well why sunlight sometimes interferes and makes it so you have to point very precisely at the TV and might need multiple tries, while it's very reliable at night. | 288 | en |
how does a capacitor work? | It stores up energy and gives it back, but it reacts differently to different frequencies of the circuit it's attached to. Because it reacts to frequency, designers can create math functions with the capacitor and two other components, the resistor and the inductor. These other two each act differently in the presence of changes in voltage and current in a circuit, and those reactions are predictable with math. So they can make a circuit that blocks high frequencies and permits low, or vice-versa, or more complicated reactions. How a capacitor works is, when you apply a voltage across its two terminals, current (electrons in motion) fills up the capacitor with a charge that's based on the amount of the voltage and the value of the capacitor. It takes current to fill or drain a capacitor, and that current is limited by the circuitry. So there's a non-zero amount of time required to change the voltage and charge on a capacitor. That change in voltage, times the capacitance, tells you the current flowing. Double the voltage, double the current. Halve the capacitance, halve the current. This ability to hang on to a voltage until the appropriate current flows makes capacitors useful in another way. They can reduce power spikes that would otherwise appear at the power and ground terminals of a chip, so if you look at the chips on a circuit board you'll see capacitors, right next to them, protecting those chips from noisy power. A side note, I have a friend who is fond of asking the same question. He answers it himself, "It works by FM." ??? "F#€ & ing Magic." Edit: probably the longest comment I've ever written and it's on f#€ & ing capacitors. | 288 | en |
Why is it OK to compare and draw conclusions from data where there are two samples of very different size? | Sample size is important on its own as it relates to the statistical “power” of a study. Power is about how large of a sample size you need to detect a statistical difference between variables with a given amount of certainty. For example, let’s say we have a two-sided coin, and we don’t know whether it’s a fair coin (i.e. 50/50 odds). If we flip it twice and we get the same side both times, does that mean that it’s not a fair coin? Maybe. But what if we flip it 5000 times and it comes up heads 4750 of those times? Would we be suspicious? We’d be more certain that it wasn’t a fair coin, and we’d have a fairly good idea of the odds. That’s statistical power as it relates to sample size. The other concept in some studies is generalizability and it relates somewhat to power. If we look at a population of 100 people and we find that 80 of them like cold weather, could we then say that 80% of people like cold weather? Again, maybe. But what if I told you that those 100 people all live in Maine and are between the ages of 18-24. We might not be so certain that we could apply the data from those 100 people and make conclusions about people in general. But, if we have a large enough sample, we might be able to find that we have a diverse group of people different locations and different ages and other demographics, and we might be able to generalize our findings. That’s generalizability. Combining these ideas gives you a sense of how we can use smaller sample sizes to imply information about larger sample sizes. | 288 | en |
if you light a lighter in front of a TV, why does the reflection show 4 tiny rainbows around the flame? | This is to do with, not the display itself, but the layers of diffusers that make up the backlight behind the display An LCD TV consists of a backlight and an LCD panel. The backlight's job is to produce an even spread of light across the display. You first have an array of LEDs, but those LEDs are point sources, and you don't want lots of bright dots. So the light has to be spread out. They do this with sheets of plastic etched with fine lines. These lines bend the light and spread it out - but only in one direction. If you only had one of these sheets, you'd have an array of lines, one for each LED. So instead they use many sheets, each sheet with lines at an angle to the one beneath. With enough of them, the light is spread evenly. It is these fine lines etched into plastic that produces those rainbows. Each line reflects the light of your lighter when the angle is right. You get a spot of light from each line, which makes a line of light stretching away from the reflection of the lighter. But the lines are close enough that you get interference - as the angle increases, the distance the light has to travel between scratches increases, and you find places where, for one color of light, the distance the light travels is exactly one-half wavelength, so the peaks of the light waves line up with the troughs, and cancel out. When you cancel out one color of light, then you only see the other colors. This is the same effect that gives CDs and DVDs their rainbow appearance. And this explanation is way too long. | 288 | en |
How does something like a complex theoretical equation get turned into a real world application? | > real world application? Let's... Use a real world application as an example, rather than FTL travel. Let's say you want to build a wall, and to prevent it from falling over you want it to be vertical. If there isn't any wind, you can hang something heavy from a string to show you what vertical is, but if you'd like to be able to work on windy days you'll need a guy named Pythagoras to come up with a handy equation for how to put together three pieces of wood in a way that makes sure the angle between two of them is always *exactly* 90°, as long as you know how long each piece of wood is relative to the two other. All you have to do to turn it into a real world application is a bit of measuring, cutting, and arithmetic. Or let's say Pythagoras figured that out thousands of years ago and now you'd like to know where you are even if you're lost in a place without streetsigns (such as the middle of the ocean). You have the technology to put radio transmitters in space, but just using the triangulation that Pythagoras figured out and other people refined *doesn't work* until some guy named Snell figures out how to predict how fast light moves in various mediums, and some guy named Einstein figures out how fast *time* moves at different accelerations and velocities. All you have to do is fit a battery powered supercomputer in your pocket that can do billions of calculations per second, launch a bunch of satellites, build insanely accurate clocks, and BAM just like that you've turned thousands of years of mathematics into a real world GPS system. | 288 | en |
How are taxes on crypto calculated? | That's not how tax brackets work. You don't get taxed 29% on all your income if your income is between $150k-$214k. You get taxed 29% on the income you make *between* $150k-$214k So if the $320k is your total gain, and you're only taxed on 50% of your gains, you would be taxed 29% on $10k (because you're being taxed on $160k of income and only $10k of that income is over $150k - ignoring any deductions for simplicity), and you would be taxed *less* on the remaining $150k (based on what the lower tax brackets are). So you would owe $2.9k for the $10k *over* that bracket you are, **plus** all the tax you owe for the lower brackets. Think of it like buckets of money. The 29% only holds about $64k worth of money (214-150), but you can only put money in that bucket once the previous buckets are full (and add up to $150k). So if you make $160k, only $10k gets put in that 29% bucket because the rest is already in the other lower taxed buckets. Example: Lets say there are 3 tax brackets - $0-$50k at 10%, $50k-$100k at 20%, $100k-$200k at 30%, and your taxable amount is $160k. You pay: * $5k for the first bracket (10% of the first $50k, reaching the $50k limit for this bracket) * $10k for the second bracket (20% of the *second* $50k, reaching the $100k total limit for this bracket) * $18k for the last bracket (30% of the final $60k remaining, reaching your total taxable income of $160k) So your total tax would be only $33k instead of the $48k it would be if your *entire* income was charged the higher 30% interest. | 288 | en |
How does probability work? | The probability of a second roll coming up a 1 is another 1 in 6. Because the result of the first roll has absolutely no effect on the result of the second roll, each individual roll has the same probability. Now, if you want to know the probability that you will roll the same number twice, then it is 1/6 * 1/6, which equals 1/36. To happen a third time, you multiply by 1/6 again, etc. Each roll reduces the probability of being the same number by an equal amount. Finally, the last kind of probability is when the first result does have an impact on the second result. You really cannot explain this with dice, so lets use colored balls: You have a bag, and in it are 6 balls. 3 balls are blue, and 3 are red. You reach in and randomly select a ball. There is a 3/6 chance of it being blue, and a 3/6 chance of it being red. So, 50-50. Lets say you pull out a red ball. If you put the red ball back, then the odds of pulling another red ball are calculated the same way as rolling the same number on a die: 3/6 * 3/6. If you leave the first ball out, you change the probability of pulling a ball the second time. Now, there are 3 blue and only 2 red. Lets say that you want another red ball. Since there are fewer possible results for a red ball (2/5), it has a different chance than if you put the first ball back. Now it is 3/6 * 2/5 to get a red ball twice. Note: all of the above #/# are to be read as fractions. | 288 | en |
Advanced Data Structures (Binary Trees, Hash Tables, Linked Lists) | The most simple data structure is a standard array, which it’s simplicity can be great for a lot of tasks! But when when you need a more purpose driven task, advanced data structures can work even better. Hash tables are my favorite, and have a lot of applications, but the main purpose is to efficiently find an element in the list. It’s sort of like a library bookshelf. If you tried to find a book thats organized like an array, you’d have a long list of titles, you’d start at the beginning of the bookshelf, and search one by one until you found the book you were looking for. A hash table instead is like the Dewey dot system, where each book has a unique number assigned to it. This number is assigned by taking the title of the book, and running it through a formula to determine its position on the bookshelf. When you want to find a book, you’d enter the book title into the formula, and it’ll spit out its exact position on the bookshelf, and you can go right to it without having to spend any time searching! Linked lists are great because they can shrink and grow at any time. An arrays size is determined and static when you create it, a linked lists size isn’t static. This is a lot more memory efficient, because you only use what you need! Binary trees are really a family of data structures, rather than just one, and are great when your application naturally flows like a tree with branches! It usually provides the a very efficient path, such as a binary search tree, which is an efficient way to find an element in an array | 288 | en |
Why is India's garbage/river pollution situation so bad? | Actual indian here... Our pollution is so bad, because the people in power don't care, and the people who do care can't ever get to power. The indian government is a carefully balanced pile of bribery and corruption built over a foundation of pure apathy and greed. While sure, there are some diligent workers at the grassroots lever, and some naive men and women higher up, noone with both the power and the means to actually do any good cares enough. Politicians here just aim to stuff as much of the tax rupees into their own private coffers before the are elected out of office. Further, the common man isn't much better. We just vote for the same greedy pigs over and over again because we cant be arsed to make an educated decision for the good of our own country. The garbage and pollution are just the tips of the massive trash iceberg just out of sight in the sewage clogged depths. Corruption, money laundering, and just plain ineptitude are so ingrained into the Indian life, that we've begun just taking it as par for the course. If you want anything done from an official stand point at all, you better be prepared to bribe liberally. And if you think it could get better with a hard reset, think again. Leave alone following meta rules about accepting bribes and ruling fairly, indians won't even follow the basic rule of "don't overtake a vehicle from the passenger's side". Though I suppose I ought to be praising my country, pride in ones own and all that, fuck it. My country sucks, and if trashing it online is the best I can do, well Imma trash as best I can. | 288 | en |
The Bill of Rights | As a baseline, consider that the Founders didn't conceive of the Constitution or the Bill of Rights as granting our civil rights; rather, there are fundamental rights that all people are born with by virtue of their humanity. The right to speak your mind, to worship as you wish, to peaceably assemble, to be free from unwarranted government searches. With the Second Amendment, there is a question as to the nature of the right we are born with. Is it *my* right to own any gun I wish? Or is it the *people's* right to collectively protect themselves? The Second Amendment is different from the others: > A well regulated militia being necessary to the security of a free state, the right of the people to keep and bear arms shall not be infringed. There isn't generally in the other Amendments an explanation of why the right is being protected, or a clause that arguably conditions the right to a particular type of body. The First Amendment, for instance, says: > Congress shall make no law . . . abridging the freedom of speech, or of the press Imagine it read: > A professional press being necessary to the operation of a free state, the right of the people to speak freely shall not be infringed If this were the formulation, you might question whether it referred to an inherent individual right to speak freely, or a right held by the people as a group to operate professional news organizations. In *Heller*, the Supreme Court determined for the first time that there was a personal right to gun ownership. That's pretty recent for a fundamental right, so the question hasn't really been fully settled as a society yet. | 288 | en |
How do perennial types of flora “die” in the Fall/Winter, but thrive and bloom again in Spring/Summer? | It's all about food production via photosynthesis. Plants have the ability to shed parts that use more food than they produce. You don't see as much die back in places where temperatures and length of day are pretty even all year long. Plants may stop blooming for part of the year, but don't need to die back because they can produce food even in the part of the year when the days are shorter. In plants with more seasonal temperature and length of day variation, you see the kind of die-back you're asking about. You see this in plants that are perennial, evergreen and annuals. Annuals produce seeds and once the length of day gets shorter and the ground cools, they stop putting out new leaves and flowers and eventually die back entirely. Perennials (and bulbs) draw nutrients back to the roots/bulbs and start dropping leaves until the point they have no visible (above the ground) parts. As long as the ground doesn't get too cold for the particular plant, or it doesn't sit in very wet soil and rot, the roots are still alive. Warm soil will trigger the plant to start new growth. Mature trees will eventually shed their lower branches even in the summer because the branches are drawing more energy than their leaves produce, so the trees "cut their losses" and shed the branches that can't photosynthesize. Evergreens have various strategies to do the same thing. On azaleas, the bigger, older leaves will turn yellow and drop in the winter so the plant no longer has to feed them. Dense plants like holly or juniper will get rid of things on the inside of the plant that don't get enough sunlight to produce food. | 288 | en |
How is it asymptomatic carriers of diseases do not suffer ill effects of the disease damaging their body if they carry enough to be infectious? | Your body is a constant, raging microbial battleground where thousands of different species of bacteria and viruses are in an unending struggle for dominance over both each other and your body as a whole. It's like a Battle Royale game where one player (your body's immune system) starts with a bunch of powerful guns and armor. The only time you actually get "sick" is when your immune system starts to run low on ammo and starts entering cheats, or if a particular bacteria gets a lucky headshot. What do I mean? Well, bacteria don't cause us to run a fever directly. Bacteria that multiply in our bodies often have a narrow temperature range that they reproduce quickly in, and fever is our immune system increasing our body temperature to try and slow an infection's reproduction cycle. Sneezing or coughing are common symptoms for diseases that spread through droplets of fluid, like COVID or the flu, and these viruses can cause those symptoms when they get enough of a foothold. So someone who is asymptomatic may still be fighting that disease, but be having an easier time with it than others. Maybe their immune system is naturally stronger. Maybe there's a second disease in their body that's fighting against the first one. Many antibiotics are produced by other microbes to attack bacteria. Or maybe it's been exposed to fewer other threats and can focus more on that particular disease. That's part of the reason why washing your hands and wearing a mask are so important. They don't just limit your exposure to COVID, they limit your exposure to MANY diseases, which means your immune system is less likely to get overwhelmed to the point that you become physically ill. | 288 | en |
Why is isn't easy for a game to utilize all the cores on a CPU? | This isn't easy to explain to people that don't know anything about programming, but the short version is this: Because a lot of things in a software program or game need to happen sequential, something you can't be sure to happen when using multiple cores. If you are only using 1 core, you can be sure that A will happen before B, so the result of A is ready when you need it for B, and B's result will be ready when you need it for C and D. If using multiple cores, you can't be sure that A will happen before B, but since B needs A to already be done, it will lock up the application until A is done and calculations on B begin. If one of the other cores is then already started on C, while the result of B still ain't done, the application will lock up again until B is done... and so forth. There are ways around a lot of this of course, but programming for true multi-core support is a lot more work then single-core support, like a massive amount of more work. A lot of multi-core games aren't even true multi-core. They are made like a single-core application would, where some parts that aren't time-sensitive are then off-loaded to the other cores. ie In an FPS game, the gfx/game engine and positition/aiming/view system could be running on one core, while the UI updates (health, ammo and the like) are then offloaded to another core, because a player won't notice if the UI is 0.03sec too late with updating your ammo count. Depending upon the game, more or less parts of the game can then be offloaded to other cores. | 288 | en |
Why do old people shake so much? | These are known as tremors, which have the tendency to worsen with age. There are multiple types of tremors that are quite common in the elderly. Some of the main ones are: • Essential tremor - the actual cause of this is unknown but is thought to have a hereditary component to it. This is the most common type of tremor. It's an action tremor, meaning that the tremor is intensified by trying to perform a movement. • Cerebellar tremor - the cerebellum is the part of the brain that controls coordination and is involved in fine motor action. Any damage to the cerebellum(commonly, small strokes) can lead to cerebellum dysfunction. This causes an intention tremor, which means that it is mostly present when trying to perform an action. Usually one side is affected more than the other, which can be an aid in diagnosis. • Parkinson's disease. This causes rigidity as well as a resting tremor, meaning it is present even at rest. This is caused by damage to the portion of the brain known as the basal ganglia, specifically the substantia nigra. While this is a complicated part of the brain, the result can best be described as inhibition of the inhibiting portions of the brain. This causes the resting tremor as well as the other features of Parkinson's. Other common causes would include things that cause stimulation, such as caffeine intake, stress, overactive thyroid, drug use or withdrawal, etc. A common mimicker of a tremor is actually muscle weakness, which can be from stroke, nerve damage, muscle damage, or just frailty amongst other causes. This can sometimes look like a tremor, when in reality it's just the muscle being weak and having difficulty fighting gravity. | 288 | en |
What happens to your body as you build endurance? Is there any change to your heart, lungs, etc.? If so, how does it compare to a "normal" person? | There's a bunch of things that happen, but I'll just list a few 1. The heart becomes stronger. The muscles in your heart will grow, meaning they can exert less of their maximum force per stroke, or push more even more blood at their new maximum effort. I once saw an older triathlete patient whose heart was in such "good shape" that he was starting to develop heart problems associated with that. 2. The other muscles you're using become stronger. Think about how much work you'd put in to lift a 100lb bag compared to a body builder. You might be exhausted, but that's easy work for the body builder. If you're gaining endurance by biking, your legs are getting stronger such that it takes less effort for each pedal stroke. You're going to tire out much more quickly if you're using 90% of your max muscle strength than 30% of it. 3. The amount of red blood cells in your blood may go up. When you're constantly low on oxygen, the body's response is to make more red cells. As a result you can carry more oxygen in your blood, reducing the work your heart has to do. 4. On a cellular level, your cells become more efficient. The classic meme that "the mitochondria is the powerhouse of the cell," is absolutely true, and your cells will produce more/bigger mitochondria. Your cells will also start to produce more enzymes associated with metabolism and energy generation. If you're offering the cells more oxygen and expecting more energy, they're going to make more of the needed machinery. There's generally not much adaptation done by the lungs, as they typically deliver more oxygen than you can take into the blood. | 288 | en |
How does the text summarizing alghorithm work? | I do text analysis/extraction for a living so this is my thing (I've only been doing it for a year, so I'm no expert). I skimmed the algorithm posted by rift95 (he deleted his comment so here is the link he posted URL_0 ) and will try to explain it (assuming I understand it correctly). Basically you rank each sentence in a paragraph based on some factors (will explain later) and the sentence with the highest score is the best summary for that paragraph. Do that for each paragraph, and you have a list of best summary sentences. Then you make a summary paragraph by chaining those summary sentences together. The ranking of each sentence is determined by how many words in that sentence appear in other sentences. (i.e. The score of a sentences is the sum of all its intersection). edit: Also a good implementation would give more important words get more points (e.g. prepositions don't give many points, keywords like location names and people names get more points). Here's an example paragraph I made: We bring you this new interesting story. This is my favorite news because we talk about the President. This Tuesday President Trump went to China. What will Trump do next? Notice that not many words in the first sentence appear in other sentences in the paragraph. This means that it will get a low score and be a bad candidate for a summary sentence. The third sentence has words like "Trump" and "President" which not only appear in other sentences, but are also proper nouns so they would be given more points. I need to go to a meeting so I'm cutting this explanation short. Hope someone found this interesting or helpful! | 288 | en |
How do mRNA-based human therapeutics work? | TLDR: They trick your body into making the harmless part of a virus that your body then reacts to and learns to defend itself against. Traditional vaccines often use a weakened or dead form of a virus to teach your immune system how to fight a particular disease. mRNA vaccines use a different method. Your body is injected with mRNA building blocks, the instructions on how to make a part of a virus. This mRNA enters your own cells tricking them to manufacture the associated proteins, or in current context the spike protein on the surface of COVID 19. Your body then reacts to that protein as foreign and attacks it with antibodies, while learning to identify and destroy those proteins if it encounters them again. This has the advantage that you don't need to inject people with a live virus, it's actually a rather ingenious way of teaching your immune system. This has the potential of helping us make vaccines much more quickly, because we can much more easily make the mRNA instructions from a known virus than modifying a virus and the mRNA is by definition likely to be harmless compared to a genetically modified virus. In addition to being highly effective, there also potentially less side effects and a quicker recovery time. Contrary to conspiracy theories the mRNA cannot enter the nucleus of the cell and therefore can't reprogram your DNA. mRNA vaccines have a alot of other potential applications as well as they could be used to tag cancer cells for example to teach your own immune system to destroy them. They could also be used for viruses like AIDS that is notoriously difficult to make a vaccine for because of what it targets. | 288 | en |
Does national debt matter? | Debt can be good or bad. The USA is in an extremely privileged "debt position" right now because it can actually issue debt that it repays at less than the inflation rate. This means people are effectively giving the USA money for the pleasure of owning its debt. However the debt of the USA is mostly due to a structural imbalance in the budget. It's mostly not due to an articulated policy. Basically when the economy is going badly, it's basic economic theory that the government **should** go into debt at these times. When the economy is going well, the budget should run a surplus. The idea is that the governments budget should be "counter cyclical". When the private sector is booming the government should "save" money and take cash out of the economy via taxation. When the private sector is down, the government should make up the slack by going into debt to boost economic activity. So it's probably still good economic policy for the government to be accumulating more debt at the moment. The problem is that there is no mechanism to reverse this. A government should establish "automatic stabilizers" to achieve counter-cyclical policies. Normally these stabilizers take the form of welfare payments since these will automatically rise during bad times and automatically decrease during good times. Instead we are "spending" our debt via tax cuts as well as social welfare. Tax cuts don't return more money during the good times. They do the opposite. This is why the US debt is worrisome. There's no mechanism to return the budget to surplus during good times apart from simply hoping that a larger economy will generate larger tax revenues - this isn't a true counter cyclical policy. | 288 | en |
If the voice we hear when we talk is different than our actual voice how is it that we are able to do accurate impressions? | Hi, trained vocalist/singer/voice over here. The phenomenon you’re talking about is related to how sound travels through your skull to reach your own ears. Most people are completely unaccustomed to listening the sound of their own voice that it sounds bizarre to them when they hear it played back on a recording, though this is what other people actually hear. As someone who has obviously trained their voice, and been exposed to recordings of my own voice for absolutely years, I can say that from my perspective my ‘through my head’ voice and ‘recorded voice’ don’t actually sound that different to me anymore. Maybe that my ‘through my head’ voice has more low frequency content. As for doing impressions and voices or even singing, I have to say that what I hear directly in my head and what is on the recording sound almost identical when compared with my normal speaking voice. I attribute this to paying more attention. You have to pay attention to what you’re doing and how it sounds when you do voices or sing properly. As such, the effect gradually starts to be less of an obstruction. EDIT: I’m just clarifying a point because some people are confusing my wording somewhat. > I have to say that what I hear directly in my head and what is on the recording sound almost identical when compared with my normal speaking voice. I meant, if I do voices or I sing, on a recording they sound virtually identical to how they sound when I hear me doing them. This is in contrast with my normal speaking voice, where the effect of different sound between me hearing it and the sound on the recording is more noticeable. | 288 | en |
How do computers turn a million yes and nos into a basic program? | The order of the yes's and no's matters. Let's call yes (1) and no (0). A container that hold a 1 or 0 is a *bit*. Now let's make a rule that 4 bits in a row is a *nibble*. We could choose any number, but 4 is a good number. Now I'll make another rule. There's a way to turn a nibble into an integer. The value of a nibble *abcd*: a * 8 + b * 4 + c * 2 + d. So If want to write "1" as a nibble I write "0001", and 7 is "0111". (This is the *binary number system*.) **Key idea 1: we can turn a list of "yes" and "no" into numbers (integers).** Now I'm going to make another rule. There are triplets of nibbles. The first nibble we'll call the *opcode*. The next two nibbles we'll call *operands*. They are all still nibbles. Here's a triplet. The operand is in bold. **0001** 0001 0001 I know I'm making up a lot of rules, but I want another. If the operand is **0001** (1) that means *addition* and if it's **0010** (2) that means *subtraction*. Now you know that when I write **0001** 0001 0010 it means "+" 1 2 or, rearranging to the order we're familiar with, "1+2". We just wrote one line of a program for a computer that tells it to add two numbers together. **Key idea 2: we can make a program out of a list of numbers.** That doesn't tell us how to get an answer. In a computer, the opcode selects an operator, meaning it switches on a circuit that add two numbers, and then feeds the next two numbers into the circuit. | 288 | en |
what is gamergate? Is it good or bad? | Once upon a time, a woman named Zoe Quinn made a game called Depression Quest. It was a simple, free game that just involved roleplaying depression by clicking on text, sort of like a "choose your own story" with simple animations and images. It was meant to raise awareness of what it's like to have clinical depression. Anyway, she had this boyfriend but their relationship ended. The boyfriend posted a manifesto (and I think it's fair to call it a manifesto because it's too long to be a simple rant) online where he complained about her, including allegations she cheated on him with multiple partners. Some people on the internet read the boyfriend's rant and decided this was absolutely outrageous. Gamergate claims they were fighting for ethical video game reviews, and alleged Zoe Quinn had sex with some guy in exchange for a positive review for her free to play game, later it turned into allegations that she had slept with 5 guys all involved in video game development. Gamergaters insisted it was not about hating on this woman but rather journalistic ethics, but they never talked about how every new Call of Duty game was rubber stamped with a positive review by most major gaming reviews, despite stories lacking depth and only superficial changes to multiplayer that we all are expected to pay another $60 for. Instead, they just talked about Zoe Quinn for a long time. They also got very outraged at Anita Sarkeesian. She calls herself a feminist and makes youtube videos complaining that women are objectified in games and women characters in games are supposedly confined to sexist tropes. Gamergate jumped on her and sent thousands of death threats. Then eventually people stopped caring. | 288 | en |
Why is inflation necessary? | A few reasons: - As the number of people in an economy increases, you need to increase the monetary supply to match. This is tough to do perfectly, so you side with a touch of inflation because the alternative is worse (more on that later) - It punishes stagnant money. Economies work when people are spending and investing, so a small "tax" on your money gives you motivation to put it out there in the markets or purchase goods today rather than have it sit in a coffee can. If a TV costs $1,000 today but $1,100 in six months, you are more likely to buy today - and that keeps the economy moving. - It alleviates debt burdens. As inflation increases, debt (which is a static value) becomes easier to pay off. This is helpful for people who have large amounts of debt and allows them to spend more in the economy (since they have more disposable income). It also makes taking on debt more attractive (because it gets easier to pay over time) which is good, because people who take on debt spend that money (which is good for the economy). - The most important one: it serves as a hedge on deflation. Deflation will **kill** an economy, because if money gains value by just sitting around, people are motivated to delay purchases as long as possible, which will cause massive economic slowdown. If that TV is $1,000 today, but will be $950 next month, and $900 the month after that, I'm motivated to wait to buy the TV until I just can't wait any longer. It is worth having your money lose a little value each year in order to ensure that catastrophe doesn't happen. | 288 | en |
Is there a major difference (less etymology, more sociopolitics) between ‘equity,’ ‘equality,’ and ‘parity,’ and what are the implications? | I'm not going to try and say that "equity means A and equality means B", because I've seen a few of those and I don't think they're well supported by etymology or by common usage. (There's a slightly-famous one with three kids of different heights trying to see over a fence.) The basic distinction is something like this: imagine we have Population A, a million people who average $45,000 a year, and Population B, also a million people, who average $49,000 a year, and we've got four billion dollars to distribute. One way to be fair to both groups is to treat everyone the same because they're all human beings. 4 billion divided by 2 million = $2000 so we give that amount to each person, paying no attention to which population they're from. This takes A to $47,000 for the year, and B to $51,000. I'd call this something like 'equality of treatment'. Another approach is we could try to erase the difference between the populations. 4 billion divided by 1 million = $4000, so that's perfect. We give $4000 to each person in Population A, nothing to Population B, and when we're done everybody got $49,000 this year. This one, I believe, is called 'equality of outcome'. And, of course, you could do a mix where first you give money to the poorer population until they get to some cutoff ($46,000 or whatever) and after that's done, you divvy up the remaining money among all people. You can make a case for each of those as being the most 'fair', and each of those cases will infuriate some people. It's an interesting topic and I think the best answer will depend on particulars of the case. | 288 | en |
Who do all the planet not eventually get sucked into the sun? | To get sucked in, they would have to lose their momentum and energy. But what's going to do that in space? Nothing really. A well lubricated, low friction clock pendulum can swing for a very long time, a massive planet flying through basically empty space experiences essentially zero friction. They can keep flying in a circle around the sun because they have the speed to do that and aren't losing it. But how did they all end up with enough energy to keep flying around the sun? Wouldn't some of them have less speed and a path that would eventually hit the sun? Absolutely, and that happened a few billion years ago. The current planets, moons, asteroids, and meteors in their present configurations are not all that ever existed in our solar system. Lots of things fell into each other when the solar system was young. Will they ever fall into the sun? It there a very small amount of friction slowing them? Yes. The inner planets will end up in the sun. Definitely mercury and venus. Probably earth. Probably not mars. Not because they fall it, but because the sun will grow to a red giant before it dies and engulf them. But ignoring the sun ever dying, foreseeably the planets would eventually decay. There is gravitational waves, and gravitational orbits do trigger tiny amounts of these waves that carry away energy and momentum. In a few trillion or more years, longer than the existence of the entire universe so far, the planets might fall into the sun. Sun of course by then will be a small, cold black ball rather than a star. Life as we know it will be long dead and impossible to exist. | 288 | en |
Why are some intervals calls ‘major’ while others are called ‘perfect’? | Musical intervals are defined by the ratio of the frequency of two pitches. Perfect intervals have really simple ratios.* An octave is defined by a 2:1 ratio. If your base note is 100Hz, 200Hz is an octave above it. A perfect fifth is 3:2, and a perfect fourth is 4:3. To our ears, when you play both notes in the interval at the same time, it sounds really *consonant*, meaning they don't clash with each other. They fit together perfectly, but don't have the same sort of color you get from other less perfectly consonant intervals. They sound cold and precise. A major third, on the other hand, has a ratio of 5:4. Play the two notes together and it's not *dissonant* (the opposite of consonant), exactly, but to our ears it doesn't have that same perfect, colorless quality you get with a perfect fourth or fifth. It sounds warm in a way the perfect intervals don't. It's admittedly a somewhat arbitrary distinction. There's no mathematical reason that 4:3 is perfect and 5:4 is not. But there's a definite difference in the way our ears perceive those intervals. As for the words major and minor, those come from how we construct scales. In any diatonic (normal seven-note) scale there will be two versions of each non-perfect interval, one a half step smaller than the other, using different notes as bases. We call the smaller one minor and the larger one major. \* For the pedants out there, this is technically not true in modern tuning systems (12 tone equal temperament); they're just *really close* to those simple ratios, and our ears hear them as if they were those ratios. But that's a whole other topic. Edit: some words. | 288 | en |
What major economic development(s) occurred between around the 50's and now that made it necessary for the average household to have two incomes instead of one to have a "good life"? | You're going to get a lot of answers but the truth is a lot of the damage from World War II gave the US a leg up economically for the 20 years post war. So much of Europe and Asia's working-age male population had been decimated. Barely any industrial capacity was left standing in China, Japan, Europe and Russia. Railroads, factories, supply depots, mining operations, everything had been refocused on the war effort or destroyed. Meanwhile, the US was untouched. Our factories were not bombed. The railroads and supply lines and mining operations were never disrupted. Much of our industrial capacity was actually built during the war, so America was not only *not* getting its factories bombed but it was building new factories at a breakneck pace. We had one of the lowest casualty rates of the war and nearly no civilian deaths. What does all of this add up to? America has a huge fucking advantage over the rest of the world as far as industrialization goes. For 20 years the rest of the world was rebuilding their population and industries, figuratively and literally. This is when America became the dominant economic superpower that it is. By the mid-seventies the rest of the world was beginning to catch back up to pre-war economic activity, and a natural result of that is globalization. And the natural result of globalization is the drop in the standard of living at the top of the food chain. a lot of money that was being exclusively spent on America and in America was now being spent in Japan and China and Western Europe and India, countries whose economies were left in no better shape than the rubbled cities that dotted their landscapes. | 288 | en |
how do doctors and veterinarians decide between stitches, staples, and other ways of keeping together surgeries? | Surgical Staples Much like the staples used to hold paper together, surgical staples are used to hold a wound together. Staples are easy to place, strong enough to hold a wound closed in an area that moves frequently like the abdomen, and often painless to remove. These staples, unlike office supplies, are sterile to help prevent infection in the wound. Sutures Also known as stitches, sutures are a synthetic thread that is used to sew a wound closed. They are used to close deep cuts, and are also used to close surgical incisions. Sutures are inexpensive and can be placed quickly once the area is numbed. Dermabond Surgical Glue This type of wound closure uses an adhesive much like SuperGlue to hold an incision closed. This is frequently done on small incisions that don’t require a tremendous amount of strength to be held in place for healing. The glue wears off in the days and weeks following placement, so a healthcare professional is not needed to remove it. In some cases, a small dab of surgical glue may be placed on sutures. This is done to keep the stitches from unraveling during normal activity. Steristrips Steristrips are small stripes of sterile adhesive material that are used to “tape” a wound closed. They are typically used on small incisions that do not experience a great deal of stress during the wound healing process. These strips of material are worn until they fall off, typically staying in place for about a week and falling off during or after routine bathing. A stubborn strip that is no longer needed can be gently removed after a shower when the adhesive is soft. Source: (very informative and in depth for each choice) URL_0 | 288 | en |
Difference between colonialism and imperalism | The terms are closely related and often treated as interchangeable, and the differences are largely arbitrary. Colonialism is the idea of having colonies, ie dominions away from your homeland that you own. Oftentimes this has involved exploitation by the colonial power of resources and people of the land taken over, so it's treated as a bad thing in modern parlance. Imperialism is a somewhat more general concept. Its root lies in "empire". Empire has meant different things at different times. It once meant a totalitarian government with absolute power over large areas (ie, Roman Empire). In much of the post-medieval era, especially in Europe, it meant having colonies (ie British Empire, French Empire). It was also somewhat interchangeable with modern industrial might and power, leading to terms such as "Empire State" in the US. At times imperialism/empires have been glorified and at times they've been criticized, the latter becoming the more common usage starting in the 20th century. After WWII with the elimination of virtually all colonial holdings, traditional colonialism died out. But imperialism, as before, took on varying interpretations. The postwar economic global order overseen by the United States made it difficult to impossible to maintain a large overseas empire. Yet that same order made it possible for some powerful countries (particularly the countries that won WWII) to use their economic might (and sometimes military strength) to wield power over countries with less economic strength, even though they aren't formally colonies. This has been called the 20th/21st century imperialism. And because imperialism was so synonymous with colonialism for so long, many see today's economic imperialism as being a form of colonialism, although not as direct as once before. I think the actual term is neocolonialism or something. | 288 | en |
Airplanes being able to provide Wifi (And why only now after a long time) | Things in aviation take a long time. A really long time. For instance, some US registered airliners today still don't have what we would refer to in the industry as "glass" cockpits. Meaning they don't have the computer monitor like screens, instead they have what we call "steam gauges." The name is a misnomer as no actual steam is involved, but it is used to describe the older style, analog instruments. Anyway, the reason that it's taken decades for airplanes to adapt to LCD screens (and even now the first touchscreens are barely starting to surface) is because FAA approval takes ages (as well as very thick wallets). This is a trade-off because while it is slow, it helps to ensure that any new invention will not decrease the safety of the aircraft. So relating this to the wifi provided onboard newer airliners, the company who produced the wifi system had to prove, beyond a shadow of a doubt, that it would not interfere with the safe operation of the aircraft. Add to this that it isn't as simple connecting a cell phone to a cell tower, as the aircraft is above the range that cell towers can communicate with, and is travelling much faster than cell phone tower switching can handle. This leaves satellite as the only available large-bandwidth communication resource. As anyone who has used satellite internet can tell you, it sucks. So the fact that you and all of the other passengers aboard the aircraft can get wifi while crossing the Atlantic is honestly ahead of its time by aviation standards. Proof that enough money (as the incentive to sell wifi to a captive audience is high) can speed along the FAA vetting process. | 287 | en |
Why do portable FM radios only have a strong signal when their antenna is perfectly oriented, and on a related note, why does the FM signal in your call stay strong, even when the car's moving? | I'm no radio engineer, but I know a bit about radios. Radio signals travel in waves. FM radio waves are, in general, around 6 feet (2 meters) tall. The antenna size must be a matching height to the wave, or a 1/2 wavelength, or a 1/4 wavelength, 1/8th, etc in order to best receive ("tuned" to) the signal. The closer the antenna is to size of the wave, the better the performance. Little portable FM radios have little antennas, so you may need to move the antenna around. If that antenna were 6 feet tall, you probably would not have to move it around. It's easy to focus on the brand of radio to determine quality of reception. In reality you can have the best made radio in the world, but without a proper antenna attached the fanciness of your radio ain't gonna mean squat. A radio is only as good as its antenna. FM signals can fade in and out if you're a long away from the transmission site and the signal fades. Mariners and old aircraft used to use radios to find their way. They would turn their circular-shaped antenna to zero in on the strong signal source, so they could approximate their location. FM radio is line-of-sight, so it travels further across water and to aircraft than it does on land where trees, buildings, mountains, etc can get in the way. Radio transmission towers are tall to maximize line of sight reception - the taller the source, the greater the coverage area. Radio is electromagnetic energy - just like visible light is. Radio moves at the speed of light, so there's no perceivable lull in the reception, even tho it probably does "pulse" receive. | 287 | en |
Why does drinking carbonated drinks worsen the effect of spicy food? | It seems this has been studied more thoroughly than I had imagined. You see, capsaicin, the active ingredient in chili, activates these receptor proteins, which sense painful heat. As you can imagine, this fools your brain into perceiving it as heat, often painful heat. CO2 in soda has an effect on acidity, given that we have the bicarbonate buffer (don't want to get too complex, but simple Le Chatelier's principle says you can push a chemical reaction forward or pull it back by changing levels of reactants or products, and by this, adding CO2 shifts the reaction leading to a dip in pH, acidity). This acidity can be sensed also by nociceptive (pain) receptors, but not TRPV1, it activates TRPA1. So it doesn't compound on the effect of capsaicin at the molecular level, but it does so at the cellular/neuronal or perceptive level. So chili is giving you mild pain, then carbonation gives you some more pain, making you feel it got worse. I can cite some papers but there's a lot of them, just Google "carbonation and TRPA1" and pubmed will have plenty to offer. Edit: Added a word Actually this is a nice review: URL_0 Guy even mentions a Facebook page talking about combing soda with chili. But he says we don't have evidence for an interaction but they both are agonists (activators) of TRP receptors. So I suppose we can't be sure why they feel worse together but it sounds plausible they do interact judging from their mechanisms (we just don't know at what level like molecule, taste bud, neuron, or higher brain processing/gustatory cortex). Edit: apologies to everybody for bending rule 4, but thankfully others have provided good simpler versions of the explanations. | 287 | en |
Questions about technological advances/the singularity | I can answer part of your question. In recent years processing power for GPUs and CPUs is based on transistor number and transistor size. In essence, how many transistors can you cram together in a single chip or card. The more transistors the more and faster calculations can be made. In your graphics cards example, Nvidia for example presented their Turing architecture in 2018, that replaced previous architectures like Pascal. Turing has transistors that measure 12nm, while Pascal had 14nm or 16nm transistors. So turing architecture cards are faster or more capable in some ways because they have more transistors in the same space. This is a gross simplification but passing from 14 to 12nm is a big deal, as it implies a lot of progress was made in a lot of fields (nanotechnology, chemistey, engineering etc) Basically nvidia couldn't have invented all the sudden the best possible graphics card. It is a complex process that implies a lot of work from different sectors and discoveries or advancements that build upon each other. The "best cpu you can buy" bascially means there is no technology cheap enough that exists today that would make selling a better processor worthwhile for mass consumption. Something similar happens for quantum computers. They are extremely useful for some fields but they are extremely expensive to make so they will not break out of the research stage untill they can be scaled down enough to be sold at a price that benefits the manufacturer. So, TLDR: there could be better gpus/cpus today, but it would be too expensive/too complicated to mass produce. A lot of different fields need to work together to allow for you, a random customer, to get high end gear | 287 | en |
how does the government get $2 trillion dollars to lend out? | Not a dumb question at all. After all, putting your hands on $2 trillion sounds a little crazy. The answer, however, is pretty simple: debt. Just like someone buying on credit cards, governments usually spend more cash than they have available. However, unlike your average person with a huge credit card bill, countries operate under somewhat different rules. A nation's debt (called *sovereign debt*) is held by a variety of entities. The public holds about a third of it in the form of bonds and similar debt instruments. (When you buy a savings bond, you're buying a little bit of national debt!) Another nearly third is held by foreign entities like governments and investment firms. About 10% is held by the Federal Reserve. And about a quarter is held by the government itself. Simply printing money is *incredibly* dangerous for an economy. It sounds like a solid idea - we need more money, so just print it! - but it can destabilize and even completely crash an economy through *inflation*. Basically, you can think of a nation's currency as having a (relatively) fixed value. That value is divided up by the number of units (dollars, pounds, etc.) in circulation. Simply printing more dollars makes each individual dollar less valuable since you haven't increased the total value. In 2007, Zimbabwe took the "print more money" approach to solving an economic problem - by 2009, the Zimbabwean dollar had devalued so badly that one US dollar was equivalent to over two *billion* Zimbabwean dollars. The safest, simplest solution for a government, therefore, is to just add to the debt. Basically, the US will ring up another $2 trillion on a credit card that already has a $21 trillion balance. | 287 | en |
If drums produce sounds that correspond to certain frequencies (e.g., C#, F), how is it that drums, when played, do not clash with the songs in different keys? | They do, it's called frequency masking. Mix engineers put a lot of effort into dealing with it, both live and in recordings. Cymbals are a particular nuisance. They don't necessarily clash harmonically however. That's because tuning the drums with a drum key is necessary, but only for the more tonal pieces of the kit (snare, tom, kick). Pieces of the kit that can't be tuned usually come in different keys/pitches, like triangles, claves, cowbells, etc. Not everyone uses the correct pitch for a piece, or tunes for every tune, but our ears are accustomed to listening to it (unless you're really anal retentive about it). A compounding factor here is that drums, even pitched ones, have much more complex modes of resonance than other instruments. Even if it's tuned, you can get enharmonic frequencies, and our brains don't really deal with that well so we just hear it as cool noise, especially when it decays fast, as in a drum. We have less time to latch on to the fact it isn't in key. There's also the fact that when you get into physical acoustics (sound through solids) it gets weird. The speed of sound isn't constant in a solid for example, so internal reflections actually change the resonant modes as the system resonates. That and solids don't vibrate in nice ways like air in a woodwind, a string fixed at two points, or a membrane (same thing as a string, but the tension applied is in two dimensions). If you see a video of a bridge collapse due to resonance you can actually see the bridge twists, rather than moving just up/down and side to side. Same thing happens in say, a woodblock or some claves. | 287 | en |
The difference between mean and median and mode. | Mean is simply the average of all values in a set. If you have 1,1,2,3,5,8,13 in a set the mean would be (1 + 1 + 2 + 3 + 5 + 8 + 13) / 7 = 4.71 Median is the middle value in the set - the one where half the values are below it and half above. In the above set 3 would be the median because (1,1,2) are all below it and (5,8,13) are all above it. If you have an even number of values, the median is the average of the two most central values. Mode is the most common value in the set. In the above example, it would be 1. 1 appears twice, but no other value appears more than once. If two or more values occur with equal frequency, the mode is not a unique value. Means are the most commonly used of these, as it describes a starting point for talking about the distribution as a whole. Medians are primarily used to exclude extreme values. For example, the mean income of all U.S. citizens includes stupendous outliers like Bill Gates and Jeff Bezos that warp the number upwards and doesn't really describe what we'd normally view as an 'average income'. Modes aren't used all that frequently in a formal sense, although you'll often pick the mode when analyzing a data set. For example, voting tends to have a 'bimodal' distribution - people either vote Democratic or Republican. The fact that some small number of people vote for third parties doesn't matter, so we focus just on those voting for candidates who can actually win and disregard parts of the set that are not one of those two modes. | 287 | en |
Why is it harder to identify a face when the eyes are covered? | Your brain processes faces using a different, specialized circuit that is a physically separate brain location. (non ELI5: It's called the [Fusiform Face Area]( URL_0 )) This area is extra detail-oriented and processes the visual input very "deeply" for two reasons: 1. Telling people apart is very important. Mistaking a friend /family / enemy for someone else has consequences, either danger or just messing up the complex social structures that have been important to humans since always. 2. Telling people apart is HARD, because physically, faces aren't all that different from each other. Recognizing hundreds of faces requires processing them in very high detail. Processing most objects at this "resolution" would be a waste of brain power, but for faces it's worth it so your brain developed the FFA just for faces. When the FFA processes a face, the eyes are the focal point because they're the most important , giving the most clues to all the possible emotions of the face you're seeing (are they needing help? About to attack? Offering sex?) So: * Depending on the amount of censoring, the FFA might *not be activated at all*. In that case the face gets processed as a "regular object" - aka with much less detail taken in. Could you recognize hundreds of different patterns of dining fork handles? Could you even pick your own current cutlery out of a lineup of 50 different similar styles? That's the level of detail-recognition we're now talking about. But of course you could pick your friend from a line of 50 strangers. The reason why is the FFA. * Even if the FFA *is* activated for the censored face, it's most-important target feature (eyes) is missing so it's massively handicapped. | 287 | en |
What are “anti-nutrients” and do they really render foods like whole wheat bread and beans unhealthy? | This blog entry is written by a food writer, not by anybody who has had scientific training or has clinical qualifications. That's a red flag. The title is also obvious clickbait, which is another red flag. It also talks in all-or-nothing language, yet another red flag. There are red flags everywhere. First, yes, there are compounds in food which inhibit absorption of certain minerals and vitamins. BUT cooking and food preparation inactivate a lot of these and actually make the minerals more absorbable for our bodies' digestion. So while some absorption may be inhibited, it's not a black and white 0 or 100%. Probably somewhere in between. Third, some of these compounds have secondary benefits on other aspects of our health (e.g. gut bacteria). So this only looks at one function that the compounds perform. It also focuses on a single part of the food and says (good/bad) based on that. This would be like me saying that because wine contains antioxidants that we should encourage everybody to drink exclusively wine. Obviously, it's more complicated than that. Whole grains contain more than minerals and these "anti-nutrients" (a loaded word choice, IMO). Better information: [ URL_0 ]( URL_0 ) (yes, *that* Harvard). Edit: I've seen a lot of these sorts of blogs/bad nutrition information point to studies that show medical conditions (e.g. goiter) resulting from consumption of foods containing "anti-nutrients." If you look at these studies they almost inevitably result from lopsided diets which rely on a very limited range of foods providing nearly all the calories in a diet or consuming absurd amounts of a particular food or group of foods. If anything, this is an argument for diversified diets that include the full range of foods. | 287 | en |
What is keeping us from developing higher frequency lasers, such as gamma ray lasers? | This is a complex question. To start; we actually *do* have gamma ray lasers, but they have to be engineered in a special way. In a normal laser, there is the lasing medium and mirrors. The lasing medium generates the beam and the mirrors are necessary to make the beam form properly. There are more in-depth explanations on this sub but that's all you need to know for this. The energy of a laser is dictated by the medium, *however*, the light has to be reflected by the mirrors for the laser to work. Gamma ray lasers have two issues. The first is that the lasing medium has to contain extremely high energy. This is doable, but usually requires things like nuclear reactions, and as such is quite a challenge. Such a lasing medium will also probably generate a lot of heat, and therefore be difficult to contain. The second issue is that mirrors do not reflect gamma rays at oblique angles (angles 90 degrees to the surface). There is no known material that even comes close to reflecting gamma rays enough to make a laser. This problem is not insurmountable, as sufficiently large lasers do not actually need mirrors, but these lasers have to be quite large, which worsens the aforementioned containment and high energy problems. Now, everything I have told you only applies to conventional laser designs. We have newer systems, such as the "wiggler" which uses magnets to vibrate electrons that are moving as absolutely ridiculous speeds, and this can generate laser light of almost any frequency we want. These devices are incredibly useful, but are still very much in development, and are probably not going to fit into hand-sized tools any time soon. | 287 | en |
if someone loses their memory do they become an entirely different person without their experiences or are they the same type of person but not remember why? | Depends a lot on the exact kind of amnesia. The most common form of amnesia in movies is the loss of autobiographical long-term memory. Autobiographical memory is the ability to remember past events that have happened to you in a kind of slide show fashion - remembering your 10th birthday for example is autobiographical memory. However, these memories are stored in a different way to memories that are about knowledge, so even if you lose your autobiographical memory, you'll still retain a lot of the important stuff. For example, you could forget how you learned to speak Chinese, but still be able to speak Chinese. Memory forms a huge part of who we are as people, so personality would be very different after memory loss. But it's not the only thing that determines our personality. Even after losing your memories, you're still just as smart and cunning as you used to be, and you still know many of the same things you used to know, especially in the "skills" department. It's quite common for people with memory loss to still be very similar to the person they used to be in a lot of ways, and as they gain new memories it can be hard to tell how much they change as a result of that is change they would have been through anyway, had they not had memory loss. The most interesting part I think is that it's quite common for feelings to remain after memory loss even if memories don't. For example, when my grandfather's Alzheimers progressed to the point he could no longer remember who my grandmother was, he'd still get happy when she came to see him, and would constantly propose to her. | 287 | en |
Why is it a big deal that 1 in 200 of people alive today can trace their lineage back to Genghis Khan? | > So Genghis Khan's DNA has had 800/25 = 32 generations (more if 20) to spread around the world. In that time, an unbroken line would need to average less than 2 progeny per person per generation (1.73^32 = 40 million) to get to ~40 mio descendents now. This seems quite normal as people did tend to have a lot of children historically. > What am I missing? Your maths is good, but it's a very clean theoretical model you're using. In reality, most populations inbreed *a lot*. For example, if we look at your ancestry over the same 32 generations you describe, and assume no overlap in your family trees, we see that each generation of grand parents is twice the size of the one before. And the rung of your family tree from 32 generations ago consisted of 4.2billion individuals. Now, that's certainly much larger than the estimated world population at the time, being only 360-400 million people. ( URL_0 ) We can see here the scale of the overlapping and intermingling of heritage. Now, almost all people alive 800 years ago have very far reaching progeny at this point, and this is a result of the earlier discussed overlapping of great-great-...-great grandparents. But due to the lack of easy transport and human mobility over the last millenium, most people's genes remained largely insulated in a single population and pervading only that localised group, whereas Ghengis Khan managed to spread into and propagate inside many different world populations. Khan's promiscuity and incredible reach sets him apart. He raped a *fucktonne* of women selected from the peoples he conquered, and thus has a higher percentage of the current world population as his descendants than is typical. | 287 | en |
How do laptop companies install the Operating System into their laptops? | TLDR: Imaging/hard drive cloning on an industrial scale We use similar techniques in Industry to prepare laptops and desktops for businesses. You install the Operating System on an example machine, install the drivers and any software that you want to package with the device. Once the machine is in a state that's ready for deployment you prepare it for imaging. You run a tool call 'SYSPREP' which puts into what Microsoft calls OOBE (Out of Box Experience) which means that on the very next boot the machine randomizes certain variables to make it a unique instance of Windows (think serial number) and goes through all the various menus to do an initial setup of the machine. This is how you get a machine into the state of First Boot asking for setup, passwords etc, while still having pre-packaged programs like a demo of MS Office, and antivirus pre-installed. (aka OEM software or crapware) This machine is then imaged. Software is used to clone this prepared computers hard drive to a file. This imaging software (Norton Ghost for example) can then be used to deploy this image to any number of machines with identical hardware. So a company like HP or Dell for example makes thousands of machines and images them all using this technique. An imaging rig could be easily built to handle uploading this image to hundreds of computers simultaneously taking about 10-20 minutes per machine. In industry we typically use a Windows PE disk to run the imaging software (booting off USB of PXE ie network) but at big manufacturers they probably plug the hard drives into an imaging rig directly and then install them into computers on the factory floor and ship them out. | 287 | en |
How will Anthony Kennedy retirement affect the future in USA | The President will offer up a nominee to Congress who will then approve/disapprove after several rounds of public and private questioning. Generally speaking, nominees are approved, even if they're faced with strong opposition. The fact that Republicans control both houses of Congress means that Trump's selection is all but guaranteed. As for what it means for "the future in the USA", only time will tell, but the Court will become much more reliably and predictably Conservative. Historically, high courts have tried not to be so blatantly political, but in recent history this has become less the case, which means the verdict to many cases can be predicted with a high degree of accuracy before the case is even heard by the court. Justice Kennedy was considered a "swing" vote that would rule conservatively on some matters and more liberally on others thereby making SC decisions less predictable and guaranteed. However, the court will probably now become more biased in their rulings and is likely to become even more so when Justice Ginsberg (a liberal) retires/dies in the near future. Assuming Trump is still president, he will nominate yet another Conservative justice which will make the SC even more conservative for years and years to come despite the fact that the nation as a whole is generally become more and more liberal. There's nothing wrong with being conservative or liberal, as an individual. However, the whole point of high courts is that they should ideally rise above daily politics to find the best/most just ruling on a case, regardless of their own personal political leanings. Unfortunately, this is becoming less and less the case as more and more judges are being elected and appointed with overt political biases. | 287 | en |
if everything obeys the law of physics, is it theoretically possible to predict the future accurately if we know all of such laws? | No, and this is a foundational principle of Chaos Theory. In a non-linear dynamic system (even a system as simple as a [double pendulum]( URL_0 )), even a tiny difference in the initial conditions will have a huge impact in how the system evolves over time, even if the system is fully deterministic. The [three-body problem]( URL_1 ) has been known about for a while. An error in measurement will grow exponentially over time until the prediction is no better than if you had just put in the measurements at random (within the allowable values for the measurements). And because the error grows exponentially, how much your prediction improves doesn't grow nearly as fast as how accurately you can measure the conditions. As the error goes to zero, how long the prediction is good for does not go to infinity, but to a finite value. And that's before you throw in quantum mechanics, where the Heisenberg Uncertainty Principle puts a limit on how accurately you can measure something. So if by predicting the future, you mean "predicting every little event and its consequences", then no that's not possible even in theory. And things like weather forecasts now take that into account. Rather than making one prediction, they make lots and lots of them with tiny little variations in each one and see how each plays out. The actual forecast is then more statistical in nature. However, that doesn't mean that predictions are entirely useless because some types of outcomes are more likely and some outcomes are impossible. With the three-body problem for example, if there are two large bodies and one small one, the most likely outcome is that the small body is ejected from the system. | 287 | en |
if someone knows how to play the piano, and sat down at a organ, would they be able to play the organ without any practice? | Have played both piano (for many years) and organ (just 1 or 2 yrs) so I have first hand experience. First, the obvious difference is that the organ has a pedalboard so you play the bass notes with your feet. Completely unique skill that you must learn from scratch. Secondly, the organ has stops (the knobs to the side used to change the sound). These aren't a huge difference because a lot of times you might just set the stops at the beginning of a piece and leave it. Thirdly, the organ has multiple keyboards, each of which can have its stops set separately, so each keyboard can have a different sound. But organs and pianos both have a keyboard, so if you didn't need the pedals or stops, playing the organ is just like the piano, right? Wrong. The action (how the keys respond) of the keyboard is different. The piano is velocity- sensitive and the keys have a weightier response. The organ keyboard feels more like a non-weighted digital keyboard. There is also no sustain pedal on the organ so if you want a note to hold, you must keep your finger on the key. With the piano you can cheat a bit using the pedal. So your fingering technique on the organ involves more finger substitution (where you switch which finger is on a key without lifting the key) and sometimes awkward reaches. On the piano a bigger part of the technique is how you strike each key, because that's where your expressiveness comes from. So, yes, someone who plays the piano could play the organ simply, but to be good at each instrument requires somewhat separate skill sets and ample practice on each. | 287 | en |
I've seen clips of players im games like Minecraft and others make fully functioning calculators. How is this done/possible? | This is a very good intro to some very approachable CS concepts. If my explanation is confusing, skip to the end for some YouTube links Most computers are made up of assembled "logic gates". They take a set of inputs and produce a set of outputs, the inputs and outputs are either "on" or "off", aka 1 or 0. There's a handful of "basic" logic gates. It's easiest to give examples: The NOT logic gate takes an input and outputs the opposite value; if you feed it a 1 you get a 0 and if you give it a 0 you get a 1. The AND logic gate takes two inputs and produces one output. If both of the inputs are 1, the output is 1. Anything else produces a 0. The OR logic gate takes two inputs and produces one output. If either input is 1 it produces a 1, if both inputs are 0 it products gives you 0. You can plug these logic gates together to do things. With some basic knowledge of binary numbers you can very easily create a simple adder that adds two numbers together. Fun fact: you can create every single kind of logic gate out of one kind, the NAND gate (Not-AND). In these videogames there are mechanics you can use to imitate these logic gates. All I know about Minecraft is that it uses redstone to do this. I've seen similar things in little big planet though. Look up "logic gates" on YouTube for some intro materials. It's one of those concepts that's easy visualise in video form. Once you have that down, look up how to produce a logic gate in your game of choice. URL_0 URL_1 | 287 | en |
When we hear harmony/chords in music, how does the brain *know* what the lead part or root notes are? | harmonics has a lot to do with overtones. when two notes share multiple overtones, they sound better together. the explanation is a bit too complex for text form, but i found [these]( URL_0 ) [two]( URL_1 ) videos extremely helpfull (the entire series is a really good explanation of a lot of fundamental concepts in music). so if two out of 4 notes in a chord share a lot of overtones, they will dominate the chord. the other ones are also there, but they are less important for the overall thing. think of it like a spice mix for italian cooking. rosemary and oregano will provide the base as they work very well together, but adding just a bit of sage will round the entire thing up without it becoming sage dominated. the ability to hear the parts of a chord and to determine which ones are more important is something that needs to be trained though. most people won't be able to do it without at least some sort of formal training. your training as a musician basically improved your brains ability to analyse and decipher music. same with someone trained in italian cooking, they could instanly tell which spices are dominant in a dish. & #x200B; culture does play a significant role. [gamelan]( URL_2 ) music form indonesia for example works with significantly different harmonics than western style music. the harmonics sound super weird to western listeners but would be considered normal, nice and positive by someone raised in the local culture. going back to cooking metaphors, an italian cook would have no idea what's going on in an indonesian dish, but a local chef can easily tell the important elements of the spice mix. | 287 | en |
Why pain has levels how does body work and why do we feel like the leg fracture I had last week wasn't that painful like the hand fracture I have right now . And why emotional pain is more hurtful than the physical pain even it doesn't hurt in body ? | Pain is your body's way of saying that something is wrong, and that you need to take some kind of action. That action might be that you need to avoid putting pressure on the area (like a sprained ankle), it might be to drink more water (like a headache), it might be that you actually need to seek medical help. For physical traumas (like broken bones), the amount of pain can depend on how many nerve endings are involved. A paper cut is *very* painful because nerve endings are a bit like tree branches. As you get nearer the surface, there are many more of them than there were deeper inside. This means a paper cut involves a *lot* of endings in a small area. Emotional pain is similar. It's your brain's way of reaction to something bad to avoid it in the future. This could be a loss you've suffered (so take care of things or treasure what you have), embarrassed (don't do the embarrassing thing again), worry or fear (get out of the bad situation), etc. It may also be a sign that you should seek help from someone. If that's the case, then get help! It's just as important to see someone about your emotional health as it is to see a doctor about your physical health. I feel obliged to ask (although you don't need to answer) if everything's okay? That fact that you mention two broken bones within a week, as well as emotional pain, is concerning. I don't know your situation but, if you're having problems with someone, please don't be afraid to get help. Edit: thanks for the gold, kind stranger! But please, go forth and show love to folk! | 287 | en |
. How are we able to learn behavioral traits of species never documented while alive? How are we so certain about dinosaur knowledge when it's based solely on fossils? | That question is similar to, "how is a forensic team investigating a crime able to know what happened if they never saw it?" They find evidence that was left behind that they can peice together to form a complete picture of what happened. Paleontologists do the same thing but with extinct animals. They use fossile records which can't be understated in usefulness. Some fossils are actually completely preserved in such a way that you can take it apart layer by layer and "disect" an ancient animal. You can see the remnants of the food they ate, the size and shape of internal organs, etc etc and in doing so use logical reasoning to figure out how those adaptations would have been used. Enviormental evidence helps too. A creature that builds a whole lot of nest in the same general area is most likely to be a group/pack/herd animal, for example. You also have the standard rules of evolution to help give you ideas as well. An animal that sticks out like a sore thumb or has an extreme adaptation is a clue that they specialize in some skill or trait because specializations are an evolutionary risk. (You *better* excel at it if you specialize or you've got nothing to fall back on.) Now, are they wrong sometimes? Definitely. Sometimes a hypothesis can look probable until someone finds evidence that conflicts with the idea. We saw dinosaurs as more reptilian for a long time, until people started find fossils that included examples of those dinos having feathers and other features that put them more inline with modern birds. Its a game of trial and error. The more evidence you can find, the more clear the picture can become. | 287 | en |
what do anti-histamines do to the body that reduces allergies? | It's in the name: they are *anti* (against) *histamine* (a signal your body uses to activate your immune system). Whenever you're injured or your body senses an attack, the cells around the affected area release histamine. The histamine tells that part of the body to do things like dilate the blood vessels to cause inflammation and, if near the face, to produce more mucus and tears. These are normally good responses, because they help your body fight off harmful pathogens. Allergies happen when histamine is released in response to harmless stimuli like pollen, and the histamine response is overly aggressive. Anti-histamines block that response in a number of ways. Mostly they fit into the receptors that the histamine normally fits in. When the histamine gets into the receptor, it activates the other chemical signals that cause the symptoms. The anti-histamine gets into that receptor without activating it, blocking the histamine from being able to turn it on. Sometimes the anti-histamine *do* turn on the receptor, but in the opposite way so it tries to turn *down* the immune response. So the stimulus still happens, the pollen is still in your nose and some of your immune cells are freaking out about it, but their signals never get the chance to activate all the rest of your immune response. Different drugs affect different histamine receptors (there are several) and some just block the receptor (receptor agonists) or turn it the opposite direction of histamine (inverse agonists). As a side-effect, histamine is a neurotransmitter that gets used for a number of things, including sleep-wake regulation. Histamines normally wake you up. So an inverse agonist anti-histamine, which does the opposite to the receptors that histamine would do, makes you tired. | 287 | en |
How does Proton Nuclear Magnetic Resonance Spectroscopy work? | I have experience in both NMR and EPR. Explaining it without mathematics can be challenging. In extremely simplified terms, though, imagine an entity with two possible states. Call them state 1 and state 2. Adding radio waves to the system tends to make it go to state 1. Adding a perpendicular magnetic field tends to make it go to state 2. Whenever the entity changes between state 1 and state 2 it releases energy. This energy can be detected. Most typically (but not always), an NMR machine will set a static radio frequency, and then scan the system with varied magnetic field strength. At particular points, the radio frequency tending to make the entity go to state 1 and the magnetic field tending to make the entity go to state 2 are aligned. At this point, the entity goes rapidly between states. This is called resonance. Every single transition releases energy, and these countless transitions in the system produce a powerful signal in the aggregate. This resonant point where the radio frequency and magnetic field intensities align depends on the chemical properties and environment that the entity is in. Now what is the entity? It could be a proton (hydrogen), an electron, carbon, nitrogen, etc. Although we use a special type of carbon and nitrogen, and for electrons the molecule the electron is on has to be special, too. Think of chemical shift as a measure of the chemical properties and environment of the entity you're measuring. For example, a proton that is surrounded by other atoms vs a proton kind of dangling off in space will be very different. These will have distinct and characteristic chemical shifts, and therefore the resonant point will be very distinct. | 287 | en |
How do gambling odds work? | Different types mean different things. You'll often see an American football game that has point spreads with both sides at -110. This means you have to bet 110 dollars to win 100. To win the bet you have to "cover the spread". If the Packers are favored by 4 over the Cowboys and you bet on the Packers, the Packers have to win by more than 4 for you to win that bet. If you bet on the Cowboys, they have to either win, or lose by less than 4 to win the bet. If the Packers win by exactly 4, the bet is off and you just get your money back. Then there is the moneyline. This is more common in baseball betting, but you can do it in basketball or football too if you want. With the moneyline there's no point spread, and you are just picking the winner. There will be a number listed that's the odds. If it is+200, you have to bet 100 to win 200, meaning if you bet 100 and you win, they'll give you your money back plus 200 bucks. A team with these odds would be an underdog. If it is -200, you have to bet 200 bucks to win 100. This team would be the favorite. In some contests where the two opponents are lopsided, and it's extremely likely one of them will win, you might see a line that's -1500 for the favorite, or +1500 for the underdog. Then you have regular odds bets. These are most common used for horse betting and futures bets. It might say 4/1, meaning you bet a dollar, and if you win you get your dollar back plus 4 bucks. | 287 | en |
Options Stock Buying | Options are an agreement where you have the *option* to buy or sell a stock at a certain price in the future. If I buy a *call* from you, I am entering a contract where you will sell me a stock in some company (let’s say Orange) for some price (let’s say $100) at some point in the future. If a share of Orange stock is worth *more* than $100, you need to sell it to me for $100 anyways, and I make money by buying it for less than it’s worth. If it’s worth *less* than $100, I don’t want to pay you $100 for it, so I will choose not to use my option. In this deal I either make money, or choose to do nothing, so of course there is a catch— or you wouldn’t agree to this. I have to pay you money to enter this agreement in the first place (buy the call from you). The risk I am taking is if the option is not profitable at its due date, and I choose not to use it, all the money I paid up front to get this option is wasted. There is also a *put* where I have the option to *sell* stock to you at a certain price, and in this case I am hoping the stock is worth *less* than the agreed price, because then I make money by selling it for more than it’s worth. Because it’s also an *option*, if that trade is not profitable at the due date, I can choose not to use it. But I need to pay some money up front to enter the contract, and lose that money if it’s not profitable. | 287 | en |
When a company goes bankrupt, how does that impact the owner? | It depends. most of the time the owner is separate from the company so their personal belongings aren't subject to the bankruptcy. In some cases an owner of a business won't do this. Example. You make cupcakes. You buy a little store, hire 2 people to help and sell cupcakes out of that store. You probably had to take out a loan to get that store, maybe cupcakes aren't selling great and you can't keep up on your employee's paychecks. Eventually the business just isn't making enough money and you can't afford the electric bill (can't keep the lights on) and close the business. What about all that money you owe? Maybe a few months on utilities. Maybe rent/mortgage payments for the property, maybe the last paycheck for employees? Well you are on the hook for all of that, and can't afford it so you declare bankruptcy. *you* couldn't afford it so you just tell everyone "I don't have the money to pay you" and all (well, most) of your debt is forgiven. You have to pay what you can but certain things you own are protected (your home almost always, often a car ect ect). Now if you make cupcakes and decide to open a cupcake store you could make Cupcakes LLC or Cupcakes INC. Then the company you created would buy/rent the store, would pay your employees and bills. And if the company ran out of money and declared bankruptcy, your bank account is safe because you didn't declare bankruptcy, the company did. In the first example you own the ingredients, you own the store, you own the equipment. In the second example you own Cupcakes LLC, but Cupcakes LLC is what owns the ingredients/store/equipment. | 287 | en |
How does the government actually take in and spend money? | > Is there just some big bank account, and do they just write a check/ is there some sort of government wire transfer system? The Federal Reserve (AKA The Fed) is the closest thing to a "big bank account" for the government. It's super complicated, but that is one of the Federal Reserves many functions. It's a pretty big organization and its general role is to maintain oversight of the country's economy and make sure that it stays as healthy as possible. > Every time I hear something like "US approves $55 million in spending" how do they actually spend it? Generally congress will approve spending on certain things. For example, they will allocate a certain amount of money to be spent on the military, Social Security, Etc. So this funding is what literally funds federal and (some portions of) state organizations. > Where does that money come from and who gets it? That's a complicated question. Actual money comes from the Treasury Department (who prints it) and collecting taxes. Since the Federal Reserve is where all the money is reserved, it functions somewhat similarly to a bank, in that other parts of the governement (and other organizations in general) will take out money to fund themselves. Where does the money in the Federal Reserve come from? Well, the main way is by selling debt (known as bonds or treasuries) to other organizations. Basically, they will offer these bonds to investors with pretty low interest rates (~2% is pretty normal), so if you buy a $1000 dollar bond, in 10 years you can redeem it with 2% accumulated interest. The Fed will tweak these rates in general to regulate the economy and maintain a target inflation rate. | 287 | en |
In abdominal surgery, is there a precise way in which the intestines must be placed back inside the body? | As someone who was told to just throw them back in, you can just toss them in. They have been in the same place in the body since they existed. They're muscle memory is very impressive as a result. The surgery I learned this on was an exploratory one. We were prepared for the worst when he opened this 80 year old woman up. It turned out to just be an adhesion, which has no blood supply. 1 snip and we were done. The several different instrument trays we had ready were for nothing. The surgeon gave me (the student) a once in a lifetime opportunity to "play" in her organs, and I did. He wasn't satisfied with how deep I got in there so he grabbed her intestines and tossed them up on her face and chest and then demanded "I said fucking play!" I very gently and cautiously continued to go through her anatomy despite how uneasy he made. He asked me if I was done, I confirmed I was. He told me to put her intestines back in, I told him I didn't know how. It dawned on me my professor used the words "just throw them back in" and he replied with those exact words. I scooped up her intestines in the same way you would scoop water out if a stream and put them back in. When I let them go they moved on their own back into the correct anatomical alignment and it was the coolest thing I have ever seen in person in my life. TLDR There's probably a method of putting them back correctly, but you can also just dump them in there and watch them work their magic | 287 | en |
Why didn't any other species make as many advancements as humans? | There's this book called *Sapiens* that argues that it is the human ability to communally believe in the imaginary which largely allowed us to develop to this point. Other social animals have to spend a significant amount of time developing their social structures and relationships. They have to spend time with others to learn to trust them and work together. There is a limit to how many other individuals you can keep track of socially. For homo sapiens this limit is claimed to be ~150. Because of this we have (almost) no evidence of primates or other human species such as the Neanderthal living or cooperating in groups that exceed some limit. Humans are different because we make up and tell stories about imaginary things such as a national or religious identity that large groups of people can subscribe to. This gives them something in common and a basis for mutual trust between strangers. By imaginary I don't mean that something is a lie or fake, just that it is not a real world object. Since humans who have never met can identify with each other due to this shared imaginary thing they are more willing to trust and work in a group with large amounts of strangers. Scientific and social progress is often the result of such collaborations. It also allows for increasingly large groups to concentrate their resources/capital. This is also why homo sapiens were able to easily outcompete, or perhaps directly eliminate, the other species of humans. Hundreds of homo sapiens can easily defeat a few dozen Neanderthals despite being inferior in strength and brain size. I don't know how extensive the evidence is for this theory. But on its surface it seams reasonable. | 287 | en |
Why can men keep producing children in old age but women have the menopause? | We actually don't know. We don't know why human woman experience menopause. It's a somewhat rare phenomenon in the animal kingdom too. While there are a couple of other species that also experience menopause (non-human primates, elephants, whales) it is not a common thing. Of course we got a couple of hypothesises, but nothing has been satisfactorily proven. On the non-adaptive front, there is the hypothesis that menopause is not something specifically selected for but rather just a side effect. Biologically, pregnancy requires a lot of high cost investment from females (more than from males) and it is simply harder to keep that up in late age. On the adaptive front, there are several hypotheses that menopause was something specifically selected for evolutionary. One of which is the mother hypothesis, which pretty much argues that because of the high cost of pregnancy at later age, and the higher chance of those children having defects, mothers improve the chances of their existing offspring (and thereby their genes being passed on) by being able to focus on them rather than focus on producing more kids. Another one is the grandmother hypothesis, which is similar in some ways to the mother hypothesis, but argues that menopause in women was selected for because older women can improve the chances of not just their children, but their grandchildren as well, again improving the chances of their genes being carried on. The reason why this results in female infertility (but not male infertility) is because biologically a woman will always know who her child / grandchildren are, while males could not have this certainty. So for males it would continue to be beneficial to try and conceive more children, also at late ages. | 287 | en |
How can the global economy survive while most countries are in debt, and that debt continues to grow? | Countries being in debt is a complicated topic and not exactly the best measure of their economic health when taken as a single piece of data. For instance: a lot of hullabaloo has been raised about the US's debt, but it is rarely pointed out that like 1/4 of that is owed by the US government to itself (ie: state department borrowed however much from department of interior). If there is a tipping point for global economic collapse, it's only speculative since we have not actually seen that many instances of global economic collapse. We've learned that it's probably a good idea to separate the banks that hold people's money and the banks that invest in businesses and regulate those, and it's such a reliable failure mode that not even 20 years after those regulations were lifted, we fucked it up and the banks bamboozled us into another recession. So maybe we should start there. But by and large, having debt can be good, as it allows you to invest money elsewhere and earn a return. As a micro-example: Say that you have $1,000,000 in the bank, and you find a house you want to buy for $1,000,000. You *could* pay cash for it, but you wouldn't have any spare cash left over. Or you could pay a $200k down-payment and then take out a 30 year mortgage, then invest the other $800k in an investment that should yield you ~10%, which over 30 years should make you more than the interest you're paying on the mortgage. Should that investment vehicle look like it's going to fail, you pull your initial $800k out and pay off the rest of the mortgage and keep whatever profits you've made. | 287 | en |
How does carbon dating work? | A lot of people are mentioning Carbon-14, but don't explain how it's used in testing and why. Carbon-14 is radioactive, and it's created via interaction between UV radiation and the CO2 in the air. Since the CO2 level cycled through the atmosphere, it remains relatively constant as the constant sun produces it at a constant rate. Thus, while C14 is radioactive and decays, the percent of C14 in the CO2 in the air remains essentially constant. That is if you took some air, took out the CO2 from it, and them removed the Oxygen from that, you'd have just carbon, and you could measure the C12 and C14 content, and you could computer the relative fraction, C14/C12. This number might be something like 0.01%, but the important thing is it's pretty static, and doesn't change much at all, even though C14 is radioactive and decays. Second, plants grow by sucking CO2 out of the air, throwing out the O2, and incorporating the carbon into themselves. Thus plants have a C14/C12 approximately equal to the air, when they are growing. Animals eat live plants and other animals, so they too have a C14/C12 approximately equal to the atmosphere. Once something dies though, it ceases to take in carbon. The carbon in is thus stays. The C14 however is radioactive, and it decays, which basically means it's disappears. So after 5730 years, it contains half the C14 as it did when alive. Since we know it had what the atmosphere had, and the atmosphere had, we know that if the atmosphere had a C14/C12 of 0.01%, then a C14/C12 of 0.005% means it died about 5730 years ago, and at 11460 years old it would go down to 0.0025%. | 287 | en |
What's going on between India and Pakistan and some guy sentenced to death? | Last year, Pakistan's intelligence services captured an Indian national, Kulbhushan Jadhav, within their borders. They produced a video taped confession from Jadhav, stating that he was spying for India. India claims that Jadhav was kidnapped by the Pakistani secret service from Iran, claims that a spy would not carry his own national passport with him, and claims the confession was coerced. They also claim that they requested consular access to see Jadhav 14 times, all of which were refused. Last week, the Pakistan Army announced that Jadhav was found guilty of espionage through court martial and sentenced to death. This was a complete surprise to many people, including the civilian Pakistani government, who had been working on improving diplomatic relations with India. The trial had been conducted entirely in secret and kept away from the civilian government. Nobody's sure what the intentions of the Pakistani military are, exactly, because it's difficult to believe that they'd risk major conflict with India over one spy; but India is outraged with everything about the situation, and Pakistan's civilian leadership is struggling to handle it. They risk angering their own military (which is more powerful than them) by working to release the man, but not openly working with India and letting the military go on will be a sign of weakness and demonstrate that Pakistan's military holds all the power in their country. Most recently, India has abducted a retired Pakistani colonel by luring him to Nepal with a job offer, with the intent to trade him back to Pakistan in exchange for their own national citizen. Trades like this are usually common with known spies, but this is a bit different, and it's possible that Pakistan will refuse to trade. | 287 | en |
How can the internet be running out of IP addresses? | an ip address is 4x 8 bit numbers. that's it. exactly how they're tallied and how stuff works is more complicated - there are entire qualifications half of which are taken up by various forms of subnetting. the highest value you can have in an 8 bit number is 255; it then overflows back to 0. 255(U8BIT) + 1(U8BIT) = 0(U8BIT). The "U" there stands for unsigned, basically meaning it cannot be negative. In short, the IP (internet protocol) only exists as a set of rules. There isn't one single IP server that all the others are subservient to or whatever - it's just a set of protocols that we all follow if we want to communicate concisely. We can't add an address higher than 255.255.255.255 because (among other reasons lol) that would overflow it by one bit somewhere. that would make an ip address 3x 8 bits and 1x 9 bits. How can you tell it's either one just by receiving the data over a data line? you wouldn't know where to stop reading the address considering that data sent over these lines is literally just a series of numbers. this is a much condensed version of things so be sure to reply and tell me what you'd like for me to elaborate on - there's no way the above two paragraphs can be enough for you to understand from scratch. also, we don't give every single device an ip address. we use something called NAT to facilitate ip connectivity on multiple devices connected to one gateway which has only one ip address. if we gave every device an ip address and didn't subnet anything we would probably have run out before the year two thousand. | 287 | en |
How does our internal sense of direction work? | When you are exploring your environment, your brain is storing bits of information. Just like it remembers what those trees looked like, or that house or that mountain, it also remembers these things in relation to each other EG "that big colorful tree in the front yard of that pink house". Stringing all those observations together creates a "sense" of your environment in which you can find your direction. That's called spatial awareness. Basically, you do not need to be consciously thinking about these things for your brain to be forming a map as it relates all these items together. To add on to that, there are people who claim to have a great or terrible sense of direction. There are a few factors to that, such as your interest or ability to pay attention to details, your interest in the environment in general (are you looking down at your phone?), and the way your brain naturally works. A person can both train and be inherently interested in being extra observant, which means their brains make even matter maps thus they may have a "great" sense of direction. These individuals also may be said to possess a specific form of intelligence called "visual-spatial". You can google "Theory of Multiple Intelligence" to learn more about the different types of intelligence and how it might affect one having a poor or great "sense of direction". tl;dr - your "sense" of direction is really your abstract (subconscious) understanding or interpretation of the spatial information your brain has collected about your environment around you, and how all those things relate to each other in physical location and context. From this map in your brain you can more successfully navigate your world. | 287 | en |
How is your lifestyle related to Diabetes? | It's due to insulin resistance. It means that insulin is adequately secreted in response to high blood sugar, but the cells of your body don't respond by collecting/sucking up that sugar. This then results in a persistently high blood sugar. We don't understand it completely, but there are genetic and environmental components that result in insulin resistance. Genetic components include things like insulin receptor mutations, and other genes that promotes things like high blood cholesterol. An interesting one is *where* you store your fat if you're obese. People who have a large amount of intra-abdominal fat (in your abdomen, not outside your body wall) are at increased risk of diabetes. Environmental factors like diet (high in fat), excessive caloric intake resulting in obesity, and a sedentary lifestyle without exercise, all contribute. Breakdown of glucose and insulin in a normal relationship: Your body needs nutrients, and the primary fuel is glucose (sugar). Cells need that sugar, and you're blood vessels are the highways that transport that sugar from your gut to all the cells in your body. But who regulates how much sugar should be in the blood stream? Too much and too little sugar both cause a lot of problems, so it is important that it gets regulated. That's insulin's job! After eating, there is an increase in your blood sugar. Your pancreas notices this, and then it releases insulin to tells all the cells that "dinners on the table, come and get it". The cells see that insulin and respond by taking in a lot of glucose, and therefore lowers the blood sugar to a more reasonable level. There's another hormone called a glucagon that does the opposite (increases blood sugar) during periods of prolonged fasting. | 287 | en |
How are fireworks that create complex designs made? | Basically by layering them like onions inside onions. The individual things that burn and make trails are little spherical pellets of gunpowder called stars. The gunpowder in the stars is tightly packed and glued together with a binder like starch to make them solid. Because it's solid each star will burn from the outside in so if the outermost layer of each star burned without color then deeper it was a red colored mix, and the center was sparkles, you'd get a dark spot in the middle when it goes off followed by red streaks then finishing with the sparkles. To propel them out the stars get packed around a sphere of loosely packed powder (wrapped in cardboard) making a shell. Because it's loosely packed, and confined in the cardboard it detonates instead of burning propelling the stars outward. To make shapes the stars are set into a pattern inside the sphere of loose powder. Stars closer to the center aren't thrown as far as the ones in the outside, so if you wanted, something like a smiley face just packing the stars in the shape of a face works pretty well. Getting the right orientation isn't really doable yet though so most shapes tend to be symmetric, or have multiple of the same shape shot at once so at least some will mostly be facing the right way. So no writing out letters. If you want more complicated patterns it's mostly a matter of setting up the layers correctly with time delay fuses in between each stage. And for lots of stuff you don't really even need spheres. Lots of fireworks are shaped like cylinders with stages that fire outward and burn from the bottom up. | 287 | en |
What is thermodynamics and how it is relevant in our everyday life? | Thermodynamics regulates the fundamental processes of life. Every enzyme in your body, every biochemical reaction, every component of your metabolism- from your nerves firing to your body absorbing nutrients, breaking them down and using the energy in movement and constructing new tissues- relies on thermodynamics. Without thermodynamics, you would not exist. What is it? It is a set of laws describing how energy behaves in the universe. Zeroth law: If the temperature of system A = temperature of system B, and the temperature of system B = temperature of system C, then the temperature of system C = temperature of system A. So if A=B, and B=C, then C=A. This may seem intuitive but it is important because it demonstrates that the scale of temperature is *not* relative, and without it temperature would be impossible to define with absolute values. First law: Energy can't be created or destroyed. Second law: Chaos in the universe is always increasing. Note- chaos in one area of the universe might decrease (for example, me building a car). However, this must be coupled with an increase in chaos elsewhere in the universe- building a car requires me to dig up materials from the dirt, burn coal to smelt the ore into iron, etcetera. The chaos increase elsewhere is always slightly greater than whatever order I try to impose, no matter what I do. As a whole, the chaos in the universe is *always* increasing. The measure of chaos is called "entropy," and entropy must always increase. Third law: as temperature approaches zero, entropy approaches a minimum. This provides an absolute reference point for entropy: zero. Together these four laws govern the economy of energy. All energy transactions in the universe follow them. | 287 | en |
How do broken bones know how to mend themselves e.g. how do two pieces of a rib reconnect and heal completely on their own? | So there's a layer of live tissue on the surface of bones called the periosteum as well as nerves running along the bones that "know" when the bones are broken because they will be physically broken. They will be able to detect the change in their environment from "My neighbor is another normal bone cell and he's telling me that we're chill, no need to grow or shrink" to "Oh shit, where did all of this blood come from? Where did my neighbor go?" which is mediated by a variety of chemical signals. The area between the two bones is going to form a giant blood clot in whatever space has been created inside of the body by the broken bones. Fibroblasts are going to turn this clot into granulation tissue, which is going to connect the two ends of bone. The fibrous scar tissue is then going to turn into cartilage and then bone over a period of time. Basically, cells in the bone will be like "Oh, I've got bone on this side and cartilage on that side and I'm getting signals that say I should extend this bone in that direction" and then the two processes meet in the middle. Basically, once bones are broken, there are not too many directions that they could grow in, so they just have to know that they are broken and that they should grow into the hole where there used to be bone. They also need to know when to stop growing and there are signals that mediate the transition of the scar tissue through the stages of bone formation into compact bone, but that's a lot of complex signaling that we don't need to get into. | 287 | en |
"Too big to fail." What does this mean? Why should a failed business be kept afloat by taxpayers? | Too big to fail means that if a business, usually a financial institution, fails, then the failure has a significant negative impact on the free flow of money or would destabilize the entire financial system. For example, let's say Bank of America announces tomorrow that it's insolvent. It stops making loans and cannot pay back deposits (FDIC not withstanding). Now, businesses that require a revolving line of credit cannot make payroll; workers do not get paid. People who had savings at BofA can no longer withdraw their funds. But that's not all; now other institutions are on notice that the sums they have lent BofA are frozen or may not be repaid in the short term. Thus, those other institutions face the same problem as BofA: insolvency, because a part of their funds are tied up with BofA. If there are insufficient reserves at these other institutions, then they could be insolvent. Now psychology comes into play. People see BofA beginning to fail, and next (let's say) Wells Fargo. Suddenly, no financial institution is safe. There's a run on the banks (this happened during the great depression), and it's like a domino effect: banks start to fail left and right. As each bank fails, the panic increases; monetary flow decreases significantly, and monetary flow is the lifeline of your economy. When the credit market freezes and monetary flow decreases significantly, we go into economic recession or depression. Thus, a decision was made that rather than let this panic occur, it would be better overall for the government to step in and prop up BofA to prevent it from failing. In other words, the damage caused by BofA's failure is greater than the damage caused by rescuing BofA. | 287 | en |
Why does most seafood have the same distinctive taste? | Couple of reasons. Firstly, salt. Most seafood lives in salt water, which means they're naturally saltier than other meats you eat. Secondly, Trimethylamine. This is the chemical responsible for that pungent, unmistakeable "fishy smell". All fish, crustaceans and I believe molluscs that live in sea water contain a chemical called Trimethylamine Oxide, which exists to balance out something called osmotic pressure. Basically, when you have two bodies of water separated by a permeable membrane (such as the membrane of a cell), water will move across that membrane so that there's the same "concentration" of water on each side. Salty water has a lower concentration of water than normal, which means that if something were to live in salty water, some of the water inside its cells would leak out into the sea. This causes cells to shrivel up and die, and kills the animal. To prevent this occurring, cells produce Trimethylamine Oxide, which is basically just there to make the concentration of water the same on the inside of the cell as it is in the seawater, to prevent the animal shrivelling up. Trimethylamine Oxide is harmless and has no effect on the taste of the meat. However, when the animal dies, bacteria starts to convert TMAO into TMA, which means that the way a fish smells is a strong marker of how fresh it is. Fresh fish actually tastes a lot less fishy than old fish, because it has much less TMA in it. If you were to compare fresh fish, you'd notice that they actually have a lot of subtle differences that are usually overpowered by the TMA. I strongly recommend finding some fresh fish text time you're in a harbour town. Tastes fucking great. | 287 | en |
Sleep paralysis demons (for someone who has never experienced sleep paralysis before). | Sleep is not an on/off switch; it doesn't always work perfectly. "Sleep paralysis" is actually completely normal - it would be very bad for someone to be acting out everything in their dreams, so their bodies lock up and stop them from moving while they're asleep. Usually. The problem is when part of a person is awake and the rest is not. For some people, this causes sleep-walking (mind asleep, body not). For other people, it causes monsters to come into your room and claw at you while you can't move (body asleep, mind not.) When you're in this half-asleep half-awake state, your real world and dream world mix together like an Augmented Reality horror game. You'll hallucinate sounds that aren't there, you'll sense presences moving around, you might feel things touching you. If your eyes are open, then you'll start seeing some creepy stuff in your room. Since you can't move due to the sleep paralysis, you'll probably freak out, which will cause all of these dream elements to definitely become nightmare elements. Every culture has their own distinct version of Bloody Mary, who everyone from that culture swears they've met before. It turns out that Bloody Mary is their subconscious failing to recognize their own reflection in a dusty mirror in the dark and Photoshopping it to a completely different figure. It can be a family member, a stranger, or a monster. They were told to expect a monster, so a monster they get. I believe the same thing affects sleep paralysis incidents. "Shadow people" is a common urban legend, and so most people dream up shadow people when they're paralyzed. And hell, I'm pretty sure alien abductions are the same thing. Aliens are scary. | 287 | en |
What does it mean for a problem to be NP Hard or NP Complete? | First a quick eli5 style definition of "NP": a class of problems which are very difficult to solve, but easy to verify a solution if offered, when simplified down to a Yes/No answer. The most well known example is the travelling salesman problem: given a list of cities and a complete cost table (eg: cost of a bus ride to/from every possible pair of cities), visit each city exactly once in sequence and come back to where you started for as little money as possible. Your job is to choose your visiting order. To make it a Yes/No problem, you are given a budget and asked if it's even possible to accomplish within the budget. It's actually really hard to verify for sure whether the answer is Yes or No, but if someone showed you a route, it would be really easy to verify that it is within the budget and that the answer is Yes. So with that out of the way... NP Hard problems are problems that, if for even 1 of them we could come up with a radical strategy that brings the difficulty down from "oh god it's a nightmare" to "child's play" (from the point of view of a computer), then ANY NP class problem could be brought down to "child's play" difficulty. And to be clear, ALL NP class problems are currently nightmare difficulty. An "NP Complete" problem means it is NP hard, but also in the NP category itself. There are categories more difficult than NP, and an NP-hard problem is allowed to be in these higher difficulty categories and still meet the above definition. An NP-Complete problem is also in the basic NP category. So that's why they're interesting. | 287 | en |
How does the chest cavity close up after heart surgery is performed? | Oh!!! I can answer this from the perspective of personal experience! I’ve had open heart surgery twice: once as a baby and once as a 20y0 (currently 27). So for me at least, they used a scalpel to cut the skin and then a surgical saw to cut through the sternum. Then they “crack” open the ribs to the sides to allow access to the heart. They said this can cause back pain for a little while after as the pressure of the ribs pushing back affects that. Anyway, they tinker with your ticker and when it’s time to close you up there’s different options: when I was a baby they used wire sutures that eventually get rejected out by the body and just fall out of your skin (like if you had any foreign body in your skin like a wood splinter). This time around I believe they used a special soluble glue that dissolves. It’s just there to hold the bones in place while the body does its own natural process of healing and renegerating bone. I’m not sure I can speak to the scientific jargon of how what happens but bones heal if they can and the glue just holds it in place while they do. It is a painful and slow process though. I couldn’t sleep any other way than on my back for quite a while! Happy to share lots more gross stories from the surgery if you want but it might get a bit off topic. Hope that’s helpful! Edit: while the bones heal they often have scarring or are slightly disformed. I have a few bumps along my sternum now as the bones don’t heal exactly as they were before. | 287 | en |
Before binary code and how it knows what it was doing. | Computers made using what are called logic gates. Essentially, you have two wires going into the gate and one going out. Each input wire can be turned on or off, and the output wire depends on what kind of gate it is and what the inputs are. In an AND gate, the output is turned on if both inputs are turned on, and turned off otherwise. In an OR gate, it is turned on if at least one input is on, and only off of both inputs are off. It turns out that by stringing the right combinations of logic gates in the right order, we can do more complicated things. One of the most important is that if we write numbers in binary (which only needs 0s and 1s), and then consider a wire that's off as 0 and one that's on as 1, we can do math (addition, subtraction, multiplication, division) and compare numbers (greater than, less than, etc.). Putting these more complicated pieces together, we can build even more complicated stuff, like your computer's processor. The processor has a bunch of input wires that represent a command telling it what it should do by using certain patterns of 1s and 0s and what numbers it should operate on, using a binary representation. But since those patterns of 1s and 0s are tricky to remember, we write the instructions in a more human readable way, called assembly code. Each assembly instruction then gets translated directly into one instruction composed of 1s and 0s, then stored where the processor can use it as input. Nowadays, we use other programming languages that are easier to use, and translate them into assembly code and from there into binary. | 287 | en |
how low pain tolerance and high pain tolerance works | Pain is actually a very complex process. See, what you experience as pain happens in your brain, not your nerves. Nociception (literally “harm perception”) is the process of a pain-sensitive nerve detecting a noxious stimulus and sending a message back to the brain. All peripheral nerves terminate at the spine, and pass the message on to the spine and up to the brain. But this doesn’t always result in “pain”. Firstly, there’s what’s called the pain gate. This is a spinal mechanism whereby the spine shuts out one pain stimulus in favour of another - it’s why rubbing a wound lessens the pain. The spine is literally blocking a portion of the pain stimulus in favour of the less painful rubbing. Secondly, there’s the brain itself. Whole PhDs have been written on this but the summary is the brain decides how much pain to feel based on context. Emotional state, prior experience, concentration and even language itself all have an impact on pain perception. It’s why an athlete might break their ankle but finish a race, while a person with a bad back experiences more pain when he’s having a bad day, or why injuries always seem worse at night when you have nothing else to focus on. Pain tolerance is a mix of all these factors. Some people have alternative nociception pathways (there’s even a congenital syndrome wherein a person has none at all), some have excellent mental strategies for coping and some people literally just have better things to do. Some poor people have experienced something worse and can contextualise it differently. Pain is actually impossible to objectively measure - no two people will experience the same harmful event the same way. Hope that helps. | 287 | en |
JPG vs. JPEG vs PNG photo formats | **PNG:** A PNG is what's called a "lossless," compression format. It looks for repeated data and simplifies it to save space. A simplified example would be: **RED, RED, RED, RED, BLUE** \- > becomes - > **REDx4, BLUE**. The data you put in will always be the exact data that comes out but the file sizes will be larger than JPG/JPEG for reasons I list below, mainly because *exact* colors don't tend to repeat too frequently outside of graphic design, meaning they can't compress as much. **JPG/JPEG:** First off, JPG & JPEG are interchangeable and the same thing. They're what's called a "lossy," compression format. Basically they try to throw away data that you won't notice in order to save space EX: All the pixels in the blue sky are *close* to the same color, so instead of remembering **light blue, slightly lighter blue, slightly darker blue, blue, light blue, etc.** it just remembers **blue** for all of them and then runs a similar process to a PNG to compress it down further. This means the data you put in won't be the same you get out, so you have to be careful since if you save a JPG, then edit and save it again, you have just compressed it twice and will start to lose a LOT of quality. If working in a production environment (video/photo editing, graphic design, etc.) it's best to keep your files in a **lossless** format until the very end, or you risk the quality degrading with every step. If you're final product is meant to be re-used (for example a logo or a video-intro meant to be re-edited into a larger work) *always* deliver the final product in a lossless format. | 287 | en |
What does the "in A minor" or "in D minor" in classical music songs mean? | If a piece of minor is in "A minor" or "D minor", it is telling you two things: (a) which is the tonal center, and (b) which is the quality. Both of them make "the key" of the piece and it isn't limited to classical music, modern songs (like a song by Led Zeppelin or Bruno Mars) are also in keys, but they don't include them in the title, *i.e.* Uptown Funk in D minor. A tonal center is the particular pitch where the song gravitates to, where it feels fully resolved, "at home". [Listen to this]( URL_1 ), the whole song gravitates towards A, if you were to end in any other chord, the song would feel unresolved, or incomplete. The tonal center is noted by the note letter, it can be any of the [twelve tones commonly found in western music]( URL_0 ). The quality is the "feel" of the song, so to speak. There are two qualities, major and minor, which one is being used depends on the set of notes that accompany the tonal center. With some ease, you can tell if a song is major because it feels "happy", and a minor song feel "sad". [Here you can listen to some songs]( URL_2 ) played in their original key and then they're transformed to the opposite quality, if the song is in G major, it then will be played in G minor. Some songs, like most blues, jazz, and funk, can't be quite contained inside a single quality because they're often using notes that are "outside" the original set of notes dictated by the key. In that case, the closest key is the one you have to notate in the music sheet. | 287 | en |
How is the umbilical cord connected inside the developing baby, and what happens to those connections (veins/arteries) after the baby is born and the cord is cut? | The umbilical cord contains one vein and two arteries, the vein Carrie's oxygenated blood from the mother to the fetus and it enters into the fetus' circulation via the ductus venosus that connects to the fetus' liver, this then goes into the inferior vena cava, and into the right heart. Since the lungs arent open to air, the circulation bypasses the fetal lungs via the ductus arteriosus which connects the pulmonary artery (the one right after the right ventricle, heading to the lungs in a person who has access to the atmosphere) to the aorta (the biggest vessel, that the left ventricle flows into) and then to the rest of circulation. Unoxygenated blood is returned from the fetus to the mother via the two umbilical arteries that split off near the illiac arteries (around the groin, top of your femurs area). There is also some blood flow that passes from the right atrium to the left atrium in the fetal heart through something called the foramen ovale. All of these (ductus venosus, ductus arteriosus, and the foramen ovale) close shortly after birth due to exposure to higher levels of oxygen and difference in pressures in the lungs. In like 25% of the population (rough guess but its surprisingly high) the foramen ovale doesnt close ever. The two ductus' keep constricting and I believe they actually turn into some form of connective tissue that helps with structure, but I'm not 100% on that one. It can take anywhere from 24 hours to 7 day for them to close, and in some babies with congenial heart defects, we actually give medications like indomethacin to keep them open until the baby can receive corrective surgery. Hope that answers the question! | 287 | en |
what does it really mean for isps to sell browsing history? | Basically imagine that your ISP was your mailman and every time you received mail from someone or send someone a letter he made a not of it and now he can legally sell a list of all the stuff you have send or received by mail to whoever he wants. The ISP can keep track of all the websites you visit. They now can sell databases of which websites which customers visit to advertisers. There are some limits to what they can keep track of. If you visit a website with "https" at the beginning the ISP knows that you went to visit that website but not which page on it. They know for example that you went to reddit but not which posts you made or looked at. If you use a VPN they only see you using a VPN and perhaps some information about about how much data you received but not really what and from where. Using anonymous browsing tabs or denying cookies won't protect you from your ISP snooping on you. The info they have on you is not limited to websites but basically anything that goes over the internet. What exactly ISPs do collect and sell and what the buyers do with that information is unclear. they might just decide not to bother or to only sell data without identifiers so marketeers can identify trends but not individuals. They may also decided to go all in and decided to sell lists of people who appear to be married and use dating apps to blackmailers and divorce lawyers. The important thing is that with the legal barriers gone there is nothing holding them back from doing whatever will give them the most money. | 287 | en |
Why do atoms form ionic bonds? | > How does gaining something make chlorine lose energy? Does the electon have negative energy? No. But Cl^- has less energy than the original neutral chlorine atom *and* a free electron. Energy of Cl < Energy of Cl^- < Energy of Cl + Energy of e^(-). So the reaction Cl + e^- - > Cl^- *is* exothermic. The electron doesn't have negative energy, but it has *less* energy than it would have if it were free. The energy released by attaching an electron to a neutral atom is called [electron affinity]( URL_0 ), and it's very high for the halogens (like chlorine) that tend to act as the negative ion in an ionic compound. For chlorine, you get 349 kJ/mol for it. The corresponding concept - the energy to *remove* an electron and produce a *positive* ion - is the [first] [ionization energy]( URL_2 ). For sodium, it costs 496 kJ/mol to remove an electron. Wait a minute, you say. How is it that you can get an exothermic reaction when you're getting 349 kJ/mol out of spending 496 kJ/mol? The reason is that these numbers are measured **in the gaseous phase** for both ions **in isolation**. But the final step is that those newly-formed ions are extremely attracted to one another and want to form a solid, because they're oppositely charged. Bringing the two ions together as a single solid produces an extra 500 kJ/mol or so (beyond just what you'd get condensing each out as a solid itself), and it's the attraction between the newly formed ions ("lattice energy") that is ultimately the energetic step. Forming isolated Cl^- and Na^+ would be endothermic. [See this page for a full walkthrough of the energetics]( URL_1 ). | 287 | en |
How did we find out what the nucleus of an atom looks like? | It wasn't just one experiment that leads us to this result, but for the sake of a proper ELI5 I'll talk only about Rutherford's golden leaf experiment which pretty much proved us that the atom is mostly void. So before Rutherford's experiment, we believed that atoms had a nucleus which is neutrally charged, that is it had positive particles in it and had negative particles, but due to spacing of the particles it was believed that the nucleus would as a whole be neutral. So Rutherford set out to test this theory, he did so be placing a golden leaf(a fancy name for an extremely thin layer of gold)in front of an alpha particle emitter(alpha particles are positively charged particles) and around the golden leaf he placed a detector that can detect alpha particles. So according to the model Rutherford set out to test, the alpha particles should pass through the golden leaf and hit the detector, but to his surprise and that of many others, he found out that a very small amount of alpha particles were deflected back or to the side. The results lead to the conclusion that only a very strongly charged particle can repel the alpha particles, and so an model was proposed in which the nucleus was introduced which hold the protons and around the nucleus electrons are buzzing around(this model now known as Rutherford's model is not completely correct but it did help pave the way for other better models). Now what Rutherford did was he calculated the size of the nucleus by math which originated in gambling. I could go more into depth but my explanation is complicated and long enough and would really not be an ELI5 anymore. | 287 | en |
What is really happening when a song is stuck in our head? | So there isn't a firm answer to this question. There are several theories, but the different theories don't completely agree. One idea is that catchy songs tend to be in a very short loop structure. That is, the end of part of it returns back to where it started. And since it's short, that allows the whole "loop" to be stored in short-term memory, where it's easy for us to play it back repeatedly. To hear that, listen to this, and ignore the singing, and just listen to the background instruments and the beat: URL_1 You'll notice it's the same thing, over and over (and over, and over . . . ) There's a segment about ten seconds long (two measures in musical format) that gets repeated over and over (and over, and over) through the whole song. That lets your mind capture the whole thing and repeat it in your head. A much longer section would be too long to easily remember. There's also some research that suggests that catchy music doesn't "resolve". A lot of traditional music has a clear resolution. But modern pop music in particular doesn't go to a finish, it just repeats over and over (and over, and over). Your mind expects it to resolve, but since it doesn't, your mind tries to resolve it by repeating it, and repeating it, and repeating it . . . Notice how many catchy songs just fade out rather than have a clear conclusion. Anyway, I can't close this out without giving you something that will be in your head for the next week, so here you go. URL_0 Just stick with it, it really gets going after like the five or six minute mark. | 287 | en |
A wormhole basically connects two points in space through a passage made over space. How exactly is the space "folded" to allow for this faster passage? | Wormholes are purely theoretical. The maths works for them, but there's no evidence that the physics works. Imagine having to find a path between two points on a piece of apper. There may be a whole number of different paths you could take (an infinite number), but given any two paths you can always turn one into the other by nudging it bit by bit. The idea behind a wormhole would be that there could be paths where that isn't possible; say if there is a hole in the middle of the paper; you can't nudge a path that goes around one side into a path that goes around the other side. And this leads to some interesting results; there are some maths/physics things that don't change between paths where you nudge one into the other, but might get a different result if you take a path that goes the other side of a hole. So with our wormhole, there may be two regions of spacetime that are connected via two separate sets of paths ("normally" and "through the wormhole") and that could be interesting as it could mess with causality, leading to time travel and so on. But there is no evidence that spacetime is disjointed in this way. It appears to be more like the piece of paper without the hole. The problem with the "folding a piece of paper" analogy for wormholes is that the paper is a 2-d surface being folded in a larger 3-d space. Whereas spacetime is a 4-d "surface" that isn't (as far as we know) embedded in some higher dimensional space. So it doesn't necessarily make sense to talk about "folding" spacetime and trying to join different bits together. | 287 | en |
Why do most people look and feel so terrible upon waking if sleep is renewing? | We look bad because our hair gets messed up during sleep. Our face muscles are relaxed, changing the way we look. Dehydration is an issue with a lot of people after waking up. Feeling terrible can have a few causes. Interrupted sleep is a common one. If our sleep gets interrupted we have a difficult time going through all the necessary stages of sleep to be renewed. Another common one is, that we wake up at the wrong phase of sleeping. Especially during the week if you get woken up by your alarm clock. But even without an alarm clock your inner clock might tell your body to wake up even if the body isn't at the right sleep phase to wake up. Too little sleep, if you wake up after too little sleep your body wants to continue sleeping and your just not fully renewed. Too much sleep can be a reason but I don't know why/how. In general the way we sleep is not the best way for our bodies. I still remember back when I was in school one summer I only slept when I was tired and got up when I woke up on my own. My sleep rhythm was all over the place and I frequently woke up at 4AM and took a nap during the day. I never felt tired/terrible the entire summer. It was glorious but impossible to imitate today due to not being able to sleep when I want and having stuff to do at specific times. But I still know going to bed super early (6-8PM) and waking up between 2-4AM makes me feel much better in the morning and I try to this as much as possible. | 287 | en |
How without being able to observe or communicate in a meaningful way can plants mimic other plants leaf colour / shape to deter animals from eating them? | Plants do not evolve their characteristics through observation and communication. They do not "decide" their evolution or traits. It is simple mutation and success/failure, over and over and over again. Imagine, for simplicities sake, a community of plants with leaves that are green that grow next to a community of poisonous bushes that have leaves that are yellow. Animals often eat the green leaves of the good plant, and don't eat the yellow leaves of the poisonous bush that they have learned to avoid through unfortunate prior experiences. One day there is a mutation in the offspring of one of the good plants. The mutation causes the leaves of one new young plant to be yellower than normal. An animal comes along, and avoids eating the leaves of that plant because it believes them to be related to the poisonous bush. Instead, the animal grazes on, and destroys, most of the other good green plants. Well, the yellow mutated plant survives to have more yellow leaf offspring, and continues on to take over a larger and larger segment of the plant community due to the higher rate of survival compared to the "original" green leaf plants. It's possible that, if enough of the original green plants are eaten and destroyed, that ALL of the community will have the yellow leaf traits that originated with the survival of that first mutant. A thousand years later a human notices that the yellow leaves mimic the traits of the nearby yellow poisonous bushes. The human says "I wonder how they knew to grow yellow leaves to trick the animals". The answer, of course, is that they did no such thing. It's just lucky mutations changing the fate of entire populations. | 287 | en |
if there are so many billionaires and millionaires donating such huge sums of money to charity every year,along with the general public making their small donations of course, how are there still so many in poverty without access to basic ammenities? Where is all this money going? | There's a lot going on here. To start, think of the scale of the problem. There are 3 billion (with a big bloody B) people living in poverty (less than €2.30/$2.50 per day) with 1.3 billion living in extreme poverty. Here in Ireland we have our own problems but the "average person" spends €120/$131 per day. So, to increase 3 billion people to even $50 per day for just one day, that would cost over $150 billion for one single day. For a year that'd be $ 5.475e+13. No amount of donations is going to give people basic amenities indefinitely. Because of this, most effective donation models have moved towards laying down infrastructure and eliminating barriers to education and economic growth for people in poverty. Think of "teach a man to fish" yada yada. While this has been shown to be a good idea and has long lasting positive effects, it's a slow process that only started *relatively* recently. With the scale of the problem at hand we won't see huge, major strides for a long time to come, and we are also relying on the governments of many impoverished nations to cooperate. Many regions suffer at the hands of corrupt governments or are in a near constant state of war, which of course makes it hard to make any progress. However, on a positive note, major strides HAVE been made. Many many more people DO have access to basic amenities. Education is spreading further and wider than it ever has before, and despite disputes over wealth gaps in many first world countries, globally, the situation is improving for everyone. This is a multilayered issue and this only scratches the surface, but hopefully you found this useful. | 287 | en |
How does a computer read a CD or DVD and extract the appropriate content? | The disc is spun and below it is a laser mounted on a track that moves back and forth so it can be pointed at any point on the disc as it passes over. When the laser hits the disc the light is reflected back and there is a sensor ready to detect it. However by altering the disc, either by changing the distance between the laser and the disc surface (by making a small pit in the disc) or by using special dye you can make it so that some points on the disc don't reflect the laser into that sensor. So as the disc spins the laser is essentially reading points on the disc as either "reflects light" or "doesn't reflect light", 1s and 0s to a computer which can be used to represent any computer data including audio or video. The actual patterns of 1s and 0s are slightly different then what a computer uses. This is because a series of all 1s or all 0s would be difficult to read - there needs to be a break to help keep the timing in check. So instead a larger sequence of bits (that have limits on repeats) are used to represent a smaller one - for example 10 bits on the CD might translate into 8 bits for the computer. Discs can have multiple layers (CDs have only 1 layer, the surface of the disc, DVDs can have 2, Blu-ray discs can have more) which is accomplished by making the outer layers transparent in some way - by altering the laser light you can choose which layer you are aiming the light at with the laser passing through any other layers in the way. | 287 | en |
What is the difference between a RNA vaccine and a "conventional" vaccine ? | My first try on an ELI5. I hope I'm getting it right if not let me know! Conventional vaccines (I refer here to the most traditional type here) use a killed or weakened pathogen or part of it to induce an immune response. You basically give your immune system the task to find a good target on that pathogen, so it will remember it for later. This immune response is generally aimed at specific parts of the pathogen. There are several reasons for this including the accessibility of that part on the pathogen and your own genetics. RNA vaccines are different in that the target finding has already been done by us using rational design and experience. For example in the case of SARS-cov-2, a protein on the outside of the virus is taken since it's both easily seen by our immune system and it's essential for the virus to have. So we choose the target but instead of isolating it from the pathogen, we produce a strand of RNA that codes for the target. When we administer this RNA into a human body, it will be taken up by (immune) cells which will use the code to make the target protein. Since the target protein is unknown to our body, it will elicit an immune response and we have what we want. For this to work it is essential that the target is chosen correctly. In a normal human immune response against most pathogens, multiple targets are chosen at the same type, although there are always some (or one) dominant targets that the body will go all-in on. Btw the RNA vaccine has so far not been tried in humans as far as I know. | 286 | en |
What process in our brain makes something "cute" and something else "ugly"? | The problem with trying to pin down the process is that these reactions are so highly variable. I absolutely adore all manner of little animals that others, perhaps even the majority, may find are actively ugly/creepy. Pigeons, moths, puffins, chambered nautilus, and terrestrial crabs would all be on my list of cutest animals, while others may think puffins look stupid, crabs are scary, and pigeons are street trash. And some of them are cute to me for very different reasons. Nautilus for example are basically expressionless, but the simplistic bobbing way that they move and their generally oblivious demeanour leaves a cute impression. While moths are really just cute aesthetically (and only really up close). While we typically associate a "cute" response with a parental nurturing reaction, that isn't always the case either. Sometimes it can stem from something making us feel nurtured or otherwise cared for, like a very specific sort of nostalgia. There is also a variation of "sad cute", where it's more of a general empathy rather than a parental response, but still one based on a reaction to care about the sad looking thing. Something can be cute in many different ways and cause many different reactions. And the high degree of variability indicates that our reaction is tied to us as individuals, our life experiences and our preexisting preferences, rather than a simple biological reaction to "baby traits". We find things cute because of the ways that they remind us of ourselves, of dear places that we remember or of experiences we've had. Seriously, this isn't a simple, or a singular process. Not every cute response is parental driven, and not every response is driven by aesthetic traits resembling human infants. | 286 | en |
What gives fire its shape? | When air is heated, it tends to expand. To explain why it expands - Heat is basically the measure of vibration and movement of the actual molecules within a substance. When something is solid, these vibrations don't have enough energy to stop the attractive forces between the molecules thus they stay mostly in place. When something is a liquid, the molecules have enough energy to repel a LITTLE bit from the attracting forces, but can at least move so they tend to slide over one another and create something that flows - A liquid. Something that is a gas has enough energy for each molecule that they have completely freed themselves from one another, and will expand to fill any container that they are in because they are basically just constantly slamming into one another as they move. This is what causes pressure because the molecules are constantly bouncing off of one another and forcing each other away, and WANT to move outward. The hotter something is, the more it wants to expand as the movement of the molecules increase. Thus the lower density it would have as it expands. This expansion lowers the density of the air that is being heated by the flame, as such it wants to rise upward because the cold air around it is more dense and forcing the hot air upward. Hot Air balloons work on this idea. So in essence what you are seeing is not the exact shape of the fire, but what the air that is moving upward forms it into. In space, fire would be much more stable in its shape and be mostly rounded as there is no gravity for hot/cold air to convect against. | 286 | en |
Why can a TV display different resolutions and still look crisp and clear, but on a monitor anything other than native looks terrible? | Most TVs nowadays have all sorts of fun features that increase the output quality that your normal LCD panel doesn't. One big one I see in my house every day: My LCD on my laptop is 60Hz (it redraws the screen 60 times a second) The TV in my living room, however, is 120Hz, no matter the input. It can take 1080p, at 30Hz, and upscale it to 4K, at 120Hz. It's only slightly choppier than at 60Hz, and only if you're paying close attention. I play DVDs (480p) off of the playstation 3 (which upscales to 1080p), which displays on the TV (upscaled to 4K). All of this is brought in by one thing: The graphics card. The graphics card in my TV is amazing at upscaling, and antialising. The LCD in my laptop is being pushed by a graphics card that is only outputting a digital signal; it doesn't exactly know what exactly the LCD is looking for. It may "support" smaller resolutions, but the LCD is not meant to upscale on it's own, it outputs the data sent, and makes the best of it. The graphics in the TV, however, were tailored to that screen, it has a pretty awesome idea of what the end result is supposed to look like, and takes whatever input it gets, and makes it what it should, your LCD does not have this feature, and neither does mine. & #x200B; TL;DR: Your TV usually has a computer of some kind that makes whatever input being fed into what it knows it should be, while the LCD panels on laptops usually are only made for one resolution, and is not mad to upscale smaller inputs on it's own. | 286 | en |
How does panting cool off mammals, and why doesn’t this work for humans? | What's happening is that the air moving around the dog's large mouth and throat area is causing the moisture there to dry. Moisture needs a bit of warmth to jump from "Liquid" state to "Gas" state, and as it transforms into vapour, it steals that heat from the tissues in the dog's mouth that it's next to, cooling those tissues in return. It's the same way that a slight breeze can feel really chilly right after you get out of a swimming pool compared to when you're dry - evaporation rids you of heat by the drying-up film of water stealing it from your body. So why don't humans do this? Well we can, but we're not really set up for it to do it by mouth. We have sweat glands to do it instead. Do this: pant - breathe in and out rapidly, say six times a second - for about 20 seconds like a dog would on a hot day. (Stop immediately if it starts to make you feel bad). You may actually feel your mouth getting cool so it works for us too! ...BUT. If you're like most people, by the end of that time, you're likely going to start to feel at least a little uncomfortable and maybe even a touch dizzy or have the tiniest of headaches when you stop. The reason for the discomfort that dogs seem to be immune to is because dogs have adapted to pant as a primary cooling mechanism, but humans didn't need to thanks to our sweat glands. Your rapid panting is fooling around with the automatic process of breathing, and that's messing with your body's various gas levels... and your body doesn't like that. | 286 | en |
How did Ready Player One (novel) get around copyright, trademark, etc.? | Definitely not a copyright lawyer, but in general there's an idea called "fair use" in copyright law that holds that you can use copyrighted ideas in reference, for parody, for commentary, and a few other ways, without violating the owner's copyrights. I could write a book right now where the main character makes several references to his hero, Batman, because it would be a limited reference that is used as a detail in my creative work. What I couldn't do is write a story where Bruce Wayne/Batman is the main character, because then I'm attempting to profit off of a major use of someone else's intellectual property. And I couldn't use Batman as a part of the advertising, either. At least not without permission. Most of what's happening in Ready Player One is stuff like that - references to classic characters, films, games, comics, etc. The kind of stuff that would fall within fair use. I think it's probably likely that the publisher's lawyers reached out to some of the owners as a courtesy, but it wouldn't have been a big case anyways. The movie, on the other hand, actually used the images of a lot of those characters as well, which is a whole 'nother can of worms. Odds are that Spielberg and the legal team actually would have to go out and get permission for a lot of them (aside from the ones owned by the production companies, those would be easy!), but in general I wouldn't imagine it to be too hard to get with a name like Spielberg attached. As long as you're not defaming the property, companies often enjoy the free advertising that comes along with appearing in a big-budget movie. | 286 | en |
how do Shakespeare directors cut as much as half of a script from a production and have it still make sense? | Almost any script has a lot of extra stuff in it which is not crucial to the plot. This is not unique to Shakespeare. You could probably convey the plot of most plays and movies in just a few scenes with a few lines of dialog each. PETER PAN: SCENE 1. INTERIOR, WENDY'S ROOM Wendy: I'm bored. Peter: *enters through window* Hello! I'm Peter Pan, a magical boy who can fly with the help of a fairy. I lost my shadow, can you help? WENDY: *sews shadow back on, improbably* PETER: Come with me to Neverland for an adventure! Wendy: Okay. I am going to bring my brother and sister and whoever the fuck else is in the story, I forget SCENE 2. EXTERIOR, LOST BOYS CAMP Peter: Welcome to the Camp of the Lost Boys! We are all orphans who live here in Neverland and never grow old. Our nemesis is Captain Hook, a pirate whose hand I fed to a crocodile. Wendy: Okay. I'm a teenage girl so in accordance with our Victorian gender roles it is my natural instinct to be your mother. Lost Boys: Okay. SCENE 3. EXTERIOR, PIRATE SHIP Captain Hook: Peter Pan I have absolutely had it up to here with your nonsense and I am going to kill you. Peter: *throws Hook into mouth of crocodile* Wendy: I'm over this whole scene too. Please take me home to London or wherever. Peter: Okay. SCENE 4. INTERIOR, WENDY'S ROOM Wendy: I forget if there's a moral or other satisfying resolution to this story, but I guess this is goodbye. Peter: I must wave goodbye, but don't you cry - I'll be back each Christmas Day! *exits via window* *roll credits* | 286 | en |
How do people determine if X poison/venom is 10 million times more harmful than Y poison/venom? | /u/Bigted1800 is indeed correct, but that's not really a complete definition. For toxicity, there's so many factors that come into play that it's really hard/unbelievably unethical to test for, so we use something called the LD50. That's the Lethal Dose 50% number, i.e. *this* amount will kill half of people exposed to it. Why we use this number isn't immediately clear, so I'll provide an example. A BAC (Blood Alcohol Content) is considered "fatal" once it hits over .375. Well, that's all fine and good but people have survived .6 and people have died from .15, because due to genetics, habitual issues and blood chemistry, some people "hold" their liquor better than others. Take someone from SE Asia with characteristic "Asian Flush", alcohol allergy and it's going to take a lot less to kill them than a hard drinking slav. The LD50 accounts for this over a population and gives us and idea of when "acute toxicity" (when harm is done) kicks in. The long and the short is the LD50, even for the 50 that don't die, it's still not a good idea to reach this point and gives us a number to use. So when someones says, "Oh, fentinol is X times as toxic/deadly as heroin" it's based on a comparison of their LD50. Say 5mg is the LD50 of heroin (please don't use this as gospel truth, this is an example) and the LD50 of fentinol is .5 mg, you can say that feninol is 10x as toxic since it takes 10x less to reach the LD50. This extrapolates out to all sorts of venoms, over the counter meds, ingested poisons, the works, they all got LD50s as it's really our best guess. | 286 | en |
Why it's so difficult for countries to build nuclear weapons. | There are basically 2 kinds of practical nuclear weapons; gun-type and implosion-type. A gun-type bomb is technically piss easy to build. Take two subcritical masses of high enriched uranium (HEU) and fire them at each other so they become one supercritical mass. The design is so idiot-proof the US didn't even bother to test it before dropping the first one. The problem with the gun-type bomb is getting the HEU. You need a *massive* infrastructure of specialized industry to enrich uranium to the required level, and you need a *shitload* of uranium. Gun-type bombs also don't miniaturize well, so they're no good for long range missiles. Implosion-type bombs take a hollow sphere of plutonium, and then through a very precisely timed series of explosions implode the sphere into a tiny supercritical mass. Plutonium is comparatively easy to get. You need a nuclear reactor to make the stuff, but compared to enriching uranium the process isn't so difficult. The tricky part of an implosion bomb is the timing. Getting your explosives to detonate in just the right order and with just the right force to implode the plutonium core is very, *very* technically challenging. A few millionths of a second makes the difference between an earth-shattering kaboom and a wimpy little fizzle. Plutonium implosion bombs give you a lot of bang for your buck weight-wise, and can be shrunk to very small sizes. They're the ones you want for an ICBM or SLBM. Of course, handling any radioactive material is technically challenging. Something as simple as putting it in the wrong shape of container or having people stand near it in just the wrong way can get you a bright flash and a bunch of dead scientists. | 286 | en |
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