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6088ov | Why climate change is happening and why it's bad | Repost | explainlikeimfive | {
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"#What's happening and why? So very basically, carbon dioxide (CO2) is a \"greenhouse gas\". That means that CO2 absorbs heat very well and radiates it back towards the earth. Sunlight goes in, heat comes out, and heat from the earth gets trapped here like CO2 is a blanket. Sure, the Earth still radiates some heat away, but not as much as it used to. The more CO2 there is in the atmosphere, the worse the effect is. There are other greenhouse gases involved, too, like methane, but CO2 is the big one. Even though methane does it better, there's just *so much* CO2 that most of the warming comes from that. As the Earth warms up, it melt some of the polar icecaps. [In this gif]( URL_10 ) you can see the ice slowly shrinking over time. Keep in mind that's the average: the ice partially melts in the summer, then refreezes in the winter. Unfortunately, it's melting way more than refreezing right now. That's a huge problem because that ice is very reflective and can reflect a lot of sunlight away from the earth. Less ice means more sunlight is getting absorbed and turned into heat. So the earth is warming even faster. The oceans hold a lot of dissolved CO2, and as the water heats up a lot of that CO2 ends up getting released into the atmosphere from deep in the ocean, making the earth warm up *even faster*. At the same time, there's a lot of CO2 getting absorbed into the oceans, which makes the water more acidic which is harmful to marine life. Regardless of what mechanisms are currently running out of control, it's pretty much accepted by the vast, *vast* majority of scientists that humans started it and are still contributing to it significantly. Every time you burn something, particularly a fossil fuel like gasoline or coal, you produce CO2. [Here is a graph of the atmospheric CO2 concentrations over several hundreds of thousands of years]( URL_0 ). You'll notice it's mostly cyclical - it rises a bit, then falls a bit, then goes back up. It's cyclical even during a single year. During the northern hemisphere's spring and summer, the huge swaths of forests in Northern American and Siberia absorb literal millions of tons of CO2 during photosynthesis and trap the carbon in sugars and cellulose. Then, during the winter months, the trees shed their leaves and stop photosynthesizing as much, relying on the food they stored during the summer and releasing a significant chunk of CO2 back into the atmosphere. However, this past year in September, when the CO2 concentration will be at its lowest point of the year as the trees finish the summer photosynthesis, the CO2 concentration was *higher* than it normal would be at the end of *winter*. [Here's a chart of CO2 for the last several decades]( URL_5 ). CO2 last year reached [400 pmm]( URL_7 ), which is higher than it has been in 4 million years. We know what CO2 levels have been for millions of years by, among other things, looking at arctic and antarctic ice deep inside glaciers. That ice has been frozen and compacted under more layers of ice for millions of years, and we can test that ice and compare it to ice formed recently, and from that we can get a very good idea of how much CO2 was in the atmosphere. We can also compare tree rings and look at chemical concentrations in those samples from very old trees (even fossilized trees), as well as [looking at coral skeletons]( URL_8 ) and comparing the concentrations of certain elements. So don't let anyone tell you that we don't actually know, because scientists are studying a *lot* of different data points. [Here is XKCD's excellent temperature timeline that really helps give the scale of what's happening]( URL_2 ). The earth's average temperature is skyrocketing. Why a one or two degree change may not sound like much, remember that it's the average for the entire planet, which means there are going to be some really wild swings to get the average to move. Again, look at the XKCD timeline and consider that for tens of thousands of years the average temperature barely changed by 4 or 5 degrees C, and 4C lower than the modern average was an ice age. **TL;DR:** Humans make a lot of CO2 through industry and burning fossil fuels. CO2 is like a blanket for the Earth: it traps heat whether we want it to or not, which causes more problems that cause more warming which cause more problems, etc. #Why is it bad? Melting ice increases the volume of the oceans, along with the slight thermal expansion of the water as it heats up. That could threaten a lot of coastal cities, and since [most of the world population lives in coastal cities]( URL_6 ), that is a problem. More than likely, they won't be underwater, but they'll probably look a lot like Venice in a bad way. That also means storm surges will push farther inland, causing massive damage and making life in those coastal cities untenable, even if the buildings are literally underwater. The melting ice also affects ocean currents. The major currents are driving by temperature extremes as warm, less dense water from the tropics flows to the poles, where it gets colder, denser, and sinks down, creating space that vacuums more warm water from the tropics, and so on. But the fresh water melting from the icecaps, cold though it is, is still less dense than the saltwater. So it doesn't sink down, and instead is filling the space the warm water from the tropics would normally fill. That disrupts the ocean currents, and ocean currents drive the Earth's climate in the same way that the poles and equator drive the ocean currents - warm water heats the air above it, bringing warm, wet air over parts of the Earth that are far north and would normally be very cold without those currents. So England goes from being chilly but mild to being *very* cold. That also means less warm, wet air going over places where it normally becomes rain, leading to widespread drought. It's no coincidence that much of the US, particularly California, is experiencing the worst droughts we've had in hundreds, if not thousands of years. At the same time, those shifting weather patterns create more intense weather, so you see more and worse hurricanes, and more destructive storms that cause dangerous flooding. Which is why the American Southeast is simultaneously in the worst drought in hundreds of years *and* got hit with the worst flooding we've seen in hundreds of years. Less rain means less food. You can't grow crops without water, and you can't exactly truck water thousands of miles from the ocean to your wheat farms. The changing climate [has already destabilized parts of the world]( URL_1 ) that can't handle the droughts and associated food shortages. Many coastal communities are dependent on the ocean for food, too, with fishing. But remember the ocean becoming more acidic in addition to warming up? The coral reefs are incredibly delicate webs of life and the increasing temperatures and acidity are killing the corals [throughout the Earth's reefs]( URL_4 ). No corals means no things that eat corals, no things that hide in corals, no things that eat those things, and so on, destroying a vast food web with far-reaching implications that we can't fully understand. We're already overfishing, disrupting the ocean's food webs and running out of viable fishing options for us, so the fact that the reefs are dying is apocalyptically bad news. [We are almost certain already experiencing a mass extinction event]( URL_3 ). There is a normal background level of how many things go extinct, and we are currently experiencing extinctions at thousands of times that normal level. Biodiversity is important for preserving the delicate food webs around the world. Say one bird dies, but turns out that bird eats an insect that eats flowers, so those insects run amok and destroy huge fields of flowers. Bees rely on those flowers for food, so the bees die off, and since bees pollinate our food crop trees like apples, [without bees you don't get apples]( URL_9 ). That's one small example out of the millions of species living on Earth. Humans might be able to live when white rhinos and giant pandas go extinct, but there are a lot of species we *can't* live without. And of course, the Earth is also just getting really hot. That may not sound like a big deal, but consider how god-awful the southeast can get in the summer (I live in GA; in the summer GA turns into Satan's swampy ass crack). It's just going to get worse, and it can get *dangerously* warm, so that heat stroke just from being outside is a real possibility. So the Earth may simply become incompatible with human life. Which is obviously undesirable. We may also trigger a new ice age as the changing climate patterns cause a rapid, out of control cooling of the Earth, which would do everything above in the opposite direction (too cold for crops, too cold for species so it cripples biodiversity, etc.). **TL;DR:** Earth may literally become unlivable for humans. Species we depend on for food are dying off because they can't adapt to the changes, and we may not be able to find new solutions. War, famine, etc. are real possibilities in the coming decades.",
"I think this has been asked about 5000 times now. Did you try the search function?"
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"https://xkcd.com/1732/",
"http://www.biologicaldiversity.org/programs/biodiversity/elements_of_biodiversity/extinction_crisis/",
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608g3k | Why can hard cheese age for months while being made, but once they hit the grocery store shelves they only last a few weeks at most? | Repost | explainlikeimfive | {
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"Cheese only \"ages\" under the correct conditions, usually a specific temperature and humidity range (often around 55 degrees F). Too warm, and the wrong microbes get involved, too cold and the ones you want die, moisture condenses, etc. Often cheese is carefully maintained, rotated, brushed, brined, that kind of thing, during the aging process. Other cheeses form a thick rind which acts to keep out undesirable microbes and oxygen. Still other cheese are dipped in wax to seal them, and something like Muenster is swabbed with a bacterial solution to ripen it. Some cheeses, especially the soft cheeses like brie or camembert just have a given lifespan, and there is no magic about being sold at a shop. You buy them, and usually hold on to them until they hit their peak. Hard cheeses though can be aged for an *extremely* long time, whole, in the right conditions. Once you cut it up and take it out of those right conditions though, game over... it's like cutting a flower; you can delay the inevitable, but it's just a delay. Then you have something like parmesan, which can last pretty much forever in a store or anywhere else you care to put it. Cheese has many varieties, and some need to be eaten within days of manufacture, others are best after years in a dark, cool place, and everything in between."
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608vv6 | Why do we close our eyes when kissing? Is this innate or learned? | Repost | explainlikeimfive | {
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"[It's because we want to focus on the kiss.]( URL_0 ) We have learned to rely more on visual stimuli than on tactile so in the brain visual stimuli is superior. That means that if we kiss with our eyes open what we see will be at the center of our attention rather than the subtle feeling of kissing. If we close our eyes on the other hand it's a lot easier to focus on the kiss. You can try this on your own. Have someone kiss an area on your back. You won't feel much. Then close your eyes and try again, the feeling will be more intense ... Edit: Added source.",
"Because it's awkward to stare someone in the eye while you suck on their mouthparts, which is what it becomes if your eyes are open. Also, my understanding is that kissing is thought to be an entirely learned behavior for modern humans, despite some evolutionary basis for the practice. But those explanations (kissing was about pre-chewing tough food for infants and grew into a sign of affection by representing this maternal behavior) still revolve around the kissing *symbolizing* something, so I would classify it as a cultural trait rather than some sort of innate behavior like sneezing or seeking valuable nutrients in food.",
"We tend to close our eyes any time we are really enjoying a sensation. A spoonful of delicious ice cream, a juicy cut of steak, etc. It helps us by eliminating other input and allowing the brain to focus on the enjoyable sensation.",
"Personal antidote tells me that it's learned, because my first girlfriend yelled at me for not closing my eyes.",
"Sometimes I open my eyes to check if my SO is opening her eyes, if she is we laugh and I ruin the moment if she's not I close my eyes and continue.",
"Ever smelled something. Like really, really smelled something? What did you do? You closed your eyes, leaned back, and probably let out a big sigh after. When we do things, especially sensory things, we use body language to express what we are doing, even if doing so doesn't really help us achieve the task. We close our eyes when we use the other parts of the face so we can focus on what we are doing and ignore everything else. Also try kissing with your eyes open sometime. It's kinda fun.",
"This is not an answered question, although there are answers for *similar* questions, which you've gotten many of here.^1 To say it's innate means it happens on its own and automatically. Many people here are saying it's because your brain can't handle the stimuli of both the kiss and visualization. However, that does not make the act of closing your eyes innate. For many people, myself included, it feels more natural leave the eyes open. Interestingly, [monkeys do not necessarily close their eyes while kissing.]( URL_0 ) So my guess is that it's not innate because it's not universal, but I don't have a hard-and-fast study to back this up. 1: In Thinking, Fast and Slow, Daniel Kahneman points out that when faced with a question we can't answer, we often substitute a similar yet easier question *without realizing it.* For example, if we can't answer the question, \"is this behavior innate?\" we may instead answer the question, \"is this behavior influenced by some biological limitation which makes the result of closing our eyes more likely?\"",
"I know why my girlfriend closes her eyes when we kiss. She hates seeing me enjoying myself.",
"In middle school I saw a girl kissing her BF with her eyes open. It kind of looked like she was eating his face. It was weird enough to still remember it 20 years later.",
"This is not common in all cultures. In Asia, we tend to keep our eyes open, to watch out for predators.",
"When showing affection, a general rule of thumb is to do anything within your power to prevent the other person fleeing the room in horror.",
"Because a kiss is about intimacy, it moves beyond liking what you see and showing the other person, in very gentle and harmonious way how you feel while allowing them to share the same things with you. You experience so much sensory input during a good kiss that having your eyes open during one detracts from the experience. Kisses are like beer, proof God loves us and wants us to be happy. Close your eyes and experience one for what it is. Her breath, her scents, the smell of her makeup, shampoo and lipstick and everything. Her being in your space and you in hers and that being better than ok. And then her lips, her thighs against yours, her hands closing tightly on your hips to guide you closer ... man kisses are the best... shut up and close your eyes.",
"It is learned. Young children kiss with their eyes open. Young teenagers will kiss in the same manner but they quickly learn this \"kills the mood\". Get into someone's face with your eyes wide open! It's intimidating and used as such as a tactic. We close our eyes to convey trust, emotion, and pleasure, but it is learned. Kittens keep their eyes open when being pet, as do puppies. But cats and dogs learn to convey their trust, emotion, and pleasure, by closing their eyes. edit: typos",
"Just some insight... I have a pair of Devon Rex's , my sister immediately noticed that my female closes her eyes when I kiss her nose, she squints and lets me do it. My male on the other hand..., eyes wide open.., and recoprocates with thorough nose licking.",
"I was once told in a lecture that people started kissing with their eyes closed because they saw people do it in movies. They did it in movies because apparently kissing with your eyes open looked really weird. However, I can't find any articles to corroborate this so I'm starting to have my doubts it's true. Kind of a plausible theory at least?",
"I think that Top Gun explained it best when they sang You never close your eyes any more when I kiss your lips And there's no tenderness like before in your fingertips You're tryin' hard not to show it, baby But baby, baby I know it You've lost that lovin' feelin' Whoa that lovin' feelin' You've lost that lovin' feelin', Now its gone, gone, gone whoaohoh",
"Speaking as someone who enjoys looking into her partner's eyes at some times and just closing them and sinking into it at others, it's learned.",
"Too close to focus properly, hair touching face causing reflexive blink. That and it's awkward as fuck to be staring at someone that close",
"Yeah, I don't do that. My current girlfriend thought it was really odd when so opened her eyes and saw me starring at her. Now she's loves it, we always kiss with out eyes open.",
"The brain has difficulty processing physical stimuli and visual stimuli, which means trying to focus on both the visual aspects of keeping your eyes open and the tactile essence of kissing is unnecessarily difficult to do for your brain. Given that there is little to no reason to be looking at something so closely as your eyes could not effectively focus on it anyway, your brain just automatically tells you to close your eyes and fuckin' focus on kissin that chick, man!",
"Because stuff that close to our eyes gets blurry. our eyeballs are roughly a 50mm lens. If you've ever tried to focus a camera lens on something too close it keeps trying and trying to focus and nothing happens. IT hurts my eyes to keep trying to focus on something way to close.",
"Psychologists at Royal Holloway University show the brain is unable to cope with the combination of visual data and tactile sensation of kissing. It used to be thought that people closed their eyes while sharing a kiss because their vision could not focus on something as close up as the other person's face.Mar 20, 2016 If you would like to read the full article, follow this link: URL_0",
"Why do girls lift one foot while being kissed?",
"Kissing is weird when you think about it. Thinking of having a persons tongue in my mouth is generally disgusting. However, it is very appealing if I'm attracted to the person. Weird with a capital G.",
"I keep my eyes open and many a girlfriend has yelled at me because they think it's weird. I have to consciously remind myself to close my eyes sometimes because every girl I've ever kissed hates it. But kissing kinda seems dumb anyway. Just sucking on each other's mouths...",
"Story time. I had to learn to close my eyes. My first kiss I a) did the goldfish - technique got rated 0/10 and b) had eyes wide open, no blinking... she was a foot shorter than me and very petite but my survival instincts said if you close your eyes you will make yourself very vulnerable... So for me closing eyes when kissing was learned.",
"My girlfriend kisses with her eyes open, it's weird. I have been caught out trying to watch tv while kissing because she doesn't close her eyes.",
"Am I the only person who sneaks peeks when I'm kissing?",
"I would say learned since I always had my eyes open when I met my boyfriend but he said it was weird. I still peek.",
"Prob cause it's too strainful on the eyes trying to focus...Not to mention it's super awkward staring someone in the eyes that close while kissing...Try it without laughing.",
"I have my eyes open when I kiss the majority of the time. I only close them sometimes because it feels awkward to have them open when everyone else closes them..",
"I kissed a girl in school with my eyes wide open like a fish ,, and I got made fun of for at least a year . It was hilarious, I never made that mistake again . It's definitely learned",
"Personally I can't help but to close my eyes cause it's just so enjoyable. People that have a partner can definitely relate to this I believe. And for those that they don't have I'm pretty sure they will find out when the time comes.",
"Learned for me. I very clearly remember thinking \"Wait. She closed her eyes. Does that mean I should? Probably. Maybe she's just really enjoying it? No. That's unlikely. Yeah. I should close my eyes.\" But by then I'd overthought it, and ended up missing. She ended up asking if I was trying to eat her nose. We didn't date long.",
"Because kissing with your eyes open is like staring in surprise as a predator tries to eat your tongue. Well, to most people at least! It's learned and reinforced by negative attitudes towards kissers who keep their eyes open. Kissing itself varies aming cultures, both in intensity and type. Of course, focusing on tactile stimuli etc. provide and extra incentive to keep those eyes closed, but kissing is (to begin with) a learned act.",
"The hardest part of your question is if it's learnt or innate because some of what we think is innate is actually learnt, for example, since children we see people kissing on movies or TV and they close their eyes while doing it, so we may pick up on that since there are many ways of learning. Personally, I think (and there is no scientific background behind my proposition, so bear with me) that we close our eyes because we are engulfed by a moment of utter intimacy when we become one with another person."
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609qv3 | Why has it been so challenging for humans to create artificial wings? | Repost | explainlikeimfive | {
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"Birds have hollow bones and muscle structures designed for flight humans do not posses these things currently",
"Birds have hollow bones, no teeth, and a very different respiratory system to get more oxygen. Massive chest muscles. Very high wing to body weight ratio to reach a similar wing to body weight ratio you'd need wings like 25 feet across and chest muscles the size of a washing machine. Think about the size of the wings on a hang glider or ultralight aircraft compared to the size of the person URL_0 Take a look at this ultralight plane. Imagine instead of a small combustion engine it's an extra 75 pounds of muscle attached to his ribs, and then his arms would have to be wings as big as the wingspan of that craft. We just can't have wings that big powered by puny human muscles! Gliding is much easier, you have hanggliders and wingsuits, in both cases you need to climb or fly to an elevation because you don't make powered lift. Jetpacks have the right power ratio and size, but fuel and *searing hot exhaust* is a major issue. A gliding wingsuit is pretty much the closest you can get."
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609ykf | If raising our heart rate through exercise is healthy why is raising our heart rate with stimulants like caffeine considered bad for our hearts? | Repost | explainlikeimfive | {
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"It is dangerous based on how it causes heart rate increase. With exercise, you are increasing the muscular need for oxygen and, therefore, the cellular response from muscle to blood stream is to increase heart rate and blood flow to those muscles. Your heart rate increases, blood pumps faster, your breathing increases to increase oxygen turn over, the process continues. However, with amphetamines, you bypass all that natural signalling and cause increased heart rate and vascular constriction with no target for exchange of oxygen or co2. As such, that same reaction is dangerous without an outlet, if that makes sense. Your pumping massive amounts of blood and elevating a heart rate with no way of alleviating that pressure in the system. Your muscles aren't needing the extra blood flow so your circulatory system is just pounding away. That kind of stress is unhealthy for the system because there is no outlet (the muscles, liver, and brain don't need the extra blood flow so it's just zooming around increasing pressure within the system). Also it's a neurochemical reaction so the stimulant binds to receptors in the brain and 'fakes' the need for increased 'fight or flight' reaction so there is adrenaline in the reaction which isn't as present in exercise. The whole process is more physiological stress than healthy physiological need. The drugs fake a need, cause an extra reaction, and ultimately cause stress on a system. Repeated stress will cause system failure eventually. I hope this makes sense.",
"hoping this gets alot of replies since i am curious to know too, my theory is probably that exercise is natural and caffeine is a drug that can activate the fight/flight response which is adrenaline",
"When you exercise you can control the rates of your heart. You can speed it up or slow it down through alternating between exercise and resting. With chemical stimulants you can't regulate your heart. Your heart is on, full speed, all the time. It gets worse with harsher chemicals than caffeine. Imagine redlining your car engine for extended period of time."
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60aej7 | Why did the Concord stop flying ? | Repost | explainlikeimfive | {
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"Hello. Pilot here. There are a LOT of inaccurate replies to this post. Let me clear some things up. Concord stopped flying for a huuuuuuge range of reasons. No one factor or reason killed it by itself, but as a combination they mounted up and where eventually too much. I will list the main reasons that killed it off. **1. A tiring airframe** Aircraft have a shelf life of sorts. Unlike a car, an aircraft is exposed to a lot of stresses and strains during its operational lifetime that weaken it's structure and components. Different parts of the aircraft have different life expectancies (The engines being the largest components with the shortest life expectancy) but generally an aircraft lifespan is measured in something called cycles. Depending on the aircraft, one cycle is either one complete startup and shutdown of the engine, or one take off and landing (Regardless of how long the aircraft is actually in the air). An aircraft can only do so many of them before specific maintenance has to be carried out to extend it's life so it can do more cycles. The more it is extended, the more expensive and in depth that maintenance becomes. Eventually there comes a point where it's just not worth it and it has to be retired. Concord was getting close to this point. She was an old aircraft and extending her life further and further would soon have come with complications like shortened flight hours, restrictions of movement/speed and all kinds of things that is undesirable in a commercial aircraft. I will allude to this more later, but many people view the Paris Air France crash as the end of the Concord. It wasn't. Her airframe cycle life would have killed her off a few years later regardless, but we will touch more upon that later. **2. A reluctant maintenance company** Airbus had a contract to maintain the Concord and it was said that they where somewhat reluctant to continue on with it beyond its renewal date. Maintaining the Concord required extremely skilled people and sophisticated facilities only a company like Airbus could bring to the table. When Airbus indicated they did not want to do it any more, that was a big problem that did not really have an immediate solution. **3. A downturn in it's economy** Contrary to popular belief, Concord was always profitable. It can never be said to have been a huge source of profit for BA/AF and it might be fair to say it sometimes was closer to breaking even but it never ran at a loss. The reason for this was economy of scale. It ran on a schedule that allowed it to break even. Concord never flew with empty seats. The price of a ticket was astronomical and that reflected its operating costs. The upside of this was that flying on it was almost a zero wait experience that got you from London to New York in 4 hours 15 minutes once check in time was calculated. There where no queues at the airports or checking in three hours early or anything like that. Minimum check in was 45 minutes before the flight, it had it's own baggage check lines and security for only 160 people. Your time in the airport was kept to an absolute minimum. The downside of this was you couldn't book a flight to fit your dates, you fitted your dates round flying on Concord. An aircraft on the ground that isn't flying and carrying passengers absolutely haemorrhages money for an airline, but in the case of Concord the time spent on the ground was unavoidable so it was factored into the cost of a ticket. That being said, there was a downturn in it's economy that began to pinch into this. As fuel prices and maintenance costs rose, the ticket prices couldn't really begin to keep up, high as they where already and it was predicted its maintenance costs would outstrip what could reasonably be claimed back in it's ticket costs in the near future. This meant at some point, the aircraft WAS going to begin operating at a loss. **4. A loss of confidence and increased safety measures after the crash of an Air France Concord in Paris** Many people like to believe that the loss of the Air France Concord in Paris was the final nail in the coffin for Concord. It wasn't. In fact all other things being equal it would barely have phased BA/AF in terms of worrying about the aircraft's future as the aircraft had a near flawless safety record at that time. At some point in time, every airframe has a crash for some reason. The fact Concord had operated for so long before it's first fatal accident was a testament to the aircraft. However it was just one of the factors that weighed up against the aircraft. A lot of safety measures had to be retrofitted to the aircraft after the crash. It's worth noting though if the crash had been directly to do with a fault in the airframe then Concord would likely have been scrapped there and then. It's no secret in the aviation world that the damage to the engine and resulting fire from the tyre debris striking the fuel tanks did not destroy the Concord. Had it remained on the ground and come to a stop it would likely have been possible to get some or maybe all of the passengers off. Sadly what destroyed the aircraft was that the plane took off before it's take off speed had been achieved and the aircraft basically stalled into the ground. Therefore BA/AF where confident that with the adaptions to the engines and fuel tank strengthening the aircraft would be as safe as it could be. However they where hugely expensive to implement and BA/AF where never fully sure of being able to recoup the costs against a potentially nervous and very small (Due to the cost of a ticket) customer base. Then 9/11 happened which further had a bad ripple effect across the airline industry and Concord unfortunately had to take some of the brunt of that as well (One of the huge impacts was no longer being allowed to visit the cockpit of Concord mid flight which was often a big part of the experience). **5. BA/AF did not want to share their toys** After it was announced that the Concord's would be retired, British Airways and Air France had a multitude of offers from several aviation companies to take or buy the aircraft and continue flying them. One of the most likely offers was from Virgin Atlantic. However Richard Branson did not believe he should have to buy them after they where basically gifted to BA/AF by the French and British governments. As it turns out BA where not willing to continue operating them but they sure as hell wheren't going to let anyone else have the prestige of operating them, and as they legally owned them, they said no. It was entirely feasible they could have had a few more years in them, but BA did not want them appearing in someone elses livery. Hopefully this clears up the main reasons why Concord stopped flying. It was a shame she stopped flying when she did but make no mistake, her time was coming to an end regardless of any crashes. --- Follow up comment with answers to some questions I have been asked as this post is too long. URL_0",
"For two reasons. Firstly, was the France disaster, where a Concord took off, suffered some major malfunction, and wound up upside down on the ground, with everyone onboard dead. While it was a genuinely magnificent plane (and I did get the chance to see one arrive at my local airport once, when I was a kid), such a well-publicized disaster occurring to one of the very few Concords in the world (iirc, there were only 12 in commercial operation) killed the brand stone-dead. Work was done go recover things. After years of investigation and reengineering, Concord was prepared and readied to fly once again. A press event was arranged, and a crew of press, enthusiasts, and airline senior bods were assembled for a flight from London to New York, which they hoped would reestablish the Concord as the premier choice for those who wanted fast, luxury travel. The flight was successful, the landing event for the press went exactly to plan, and everything seemed poised for success. And then, just thirty minutes later, the first plane hit the World Trade Centre. Concord's return was overshadowed by about the single worst thing that could possibly overshadow it. The aviation industry took a long time to recover from those attacks. Concord's relaunch didn't stand a chance, and was given up on in mid 2002.",
"The Concorde was never a financial success. It cost as much as a 747 to operate, with a third of the passengers. And when you figure all the non-flight time involved in door-to-door travel across the Atlantic, it wasn't that much faster, you are still going to waste most of your day in transit. Finally, because of the sonic booms, it could only travel at full speed over the ocean. Then in 2000, Air France flight 4950 hit some debris on the runway during takeoff, ruptured a fuel tank, and wound up crashing into a hotel. Over 100 people died. The Concorde was grounded for a while, and by the time it returned to service, 9/11 happened, result in a decrease in air travel. The airplane was also badly outdated and due for a major upgrade. British Airways and Air France instead decided to pull the plug at that point.",
"On top of what other people have been saying, the relative time advantage of a faster flight disappeared. Let's say the flight is 3 hours vs 6 hours. That's twice as fast, that's a big deal. You could easily wake up in the morning, fly to Europe for an afternoon meeting, and fly back home in time for dinner with your family. Indeed, this is how they originally pitched it. Over the years, airports have become busier, security has become tighter. You can't just hop on a plane anymore. You need to show up for your flight a couple hours in advance. Factor in the extra time you spend getting to/from the airport because a lot more people fly these days. Pretty quickly, the whole advantage of having a flight that's faster starts to disappear. Even if you had the Concord available today, you couldn't really fly to Europe for your meeting and get back the same day anymore.",
"basically, it was too inefficient. everything about it was just to make it go faster. the only reason it ever flew was because back then, people were willing to pay for that. with a full tank, it could barely fly from the uk to the east coast. compared to a 747 or an a380, which can go double the distance with the same amount of fuel and carry 4-5 times as many passengers, airlines just weren't able to make enough profits to keep it flying, which is why they took it out of business. I'm not really great at explaining things quickly, but hopefully you get the idea:) p.s. my dad also told me a few years ago that it was because it was a very uncomfortable aircraft. he asked me \"would you rather spend an hour in a really cramped, uncomfortable aircraft, or two hours in a plane with lots of space where you can also get work done while you're at it?\"",
"A new Boeing 787 which is one of the most efficient commercial planes has an mpg per passenger of about 104. The concord had 14.",
"Wendover Productions YouTube channel has some good videos on the airline industry. They did one on the [Concorde] ( URL_0 ) failure. Plane was really expensive to operate because it had horrible fuel efficiency. It also could only seat about 1/3 as many passengers as a typical transatlantic flight so tickets were very expensive for what was basically just a coach seat. Those who could afford it, opted to pay the same price for a luxurious first class seat on a slower flight.",
"Vox has a really cool video about the Concord: URL_0 Its only about 10 minutes and really well edited. It pretty much tells you everything the other responses have explained but just in case you want something pretty to look at :)",
"I did a report on this is in college and it had a large part do to the safety concerns after the crash. Which was the only one to ever occur. But one reason I found was that it was too loud. NASA did a study on how the vibrations were very disruptive to the surrounding areas. One of the biggest problems was the economical cost of the plane, it what decommissioned because it wasn't marking much money, this was due to the fears of flying after 9/11. Many less people were flying so they didn't have the seats to fill required for them to make a profit. TL:DR- 9/11 a lot of people weren't flying. Sorry about the format I'm on mobile.",
"When the Concorde first flew in the 70s it was more or less the same seating as upper class in other slower planes so it was actually quite nice for business executives to fly over the Atlantic ocean in less then half the time. But it was still really expensive, far more than the regular price, to fly and the Atlantic crossing was basically the only route it could fly with some advantages because it couldn't fly supersonic overland, didn't have the long range such as the 747 and the time margins for short flights are so small it wouldn't warrant the price tag anyway. With the advent of much more luxurious regular and first class seating in 'normal' planes during the late 80s and 90s even those executives who could even afford the Concorde flights would decide to rather fly 8 hours in what is essentially a bed with tv instead of 3 hours in 'economy' seats. The only ever reason for people to fly Concorde where out of pure curiosity and for the time saved and people decided it wasn't worth the time anymore because you could fly much more comfortably. Also, one day travel time to anywhere on the planet was accepted as you spend an hour at the airport anyways. By the late 90s many of those 100 seat aircraft flew half empty when the airline needed them to be almost full to make money and those passengers often just used saved up miles to fly it out of curiosity. Add to that the 2000 crash killing all passengers, even more increased airport time post 9/11, besides the fact that the first flight after the accident was actually on 9/11 and you understand why the Concorde was retired",
"Additional - Concorde was very unpopular because IT WAS SO FREAKIN LOUD!!! URL_0 Like miles away from London Heathrow you would hear it, people complained about it all the time, and with noise regs. etc. tightening up, didnt help.",
"I asked a pilot this and one of the reasons was because they lost a significant portion of their frequent flier clients in the September 11th attacks. [Here]( URL_0 ) is an article that cites the claim",
"The short answer it is the crash of Air France Flight 4590 and 9/11. The reality is the Concord program was essentially NEVER profitable, not when R & D is thrown in. Air France & British Airways kept the tiny fleet of 12 planes in the air basically as a lost leader advertising their brand and a fair amount of corporate ego. But the double-whammy of the crash plus the plummet in air travel following the WTC attacks killed the the program. It would have have cost both airlines millions each *month* to keep the planes going.",
"Also relevant. It could only be used for trans Atlantic flight due to the Sonic boom. So the market for its use was pretty limited.",
"So [this]( URL_0 ) is a really great video that covers exactly what you're asking! TLDW, Concorde planes did fly much faster, but because of the extra fuel demands of their engines, they were extremely expensive to operate. Their cabins were also small and cramped, so clients ended up choosing business class on the longer flight that at least had the ability to extend into a bed so they could get some sleep at a cheaper price. Airlines were also changing their business model during this time to attract middle class families instead of businessmen, so the cost ended up being the biggest factor in choosing a flight. Most people didn't have the money, so Concorde flights were flying with less than half the cabin full of paying customers.",
"[This video]( URL_0 ) pretty much sums it up. Also talks about planes speed in general.",
"I lived in Bergen Beach, NY, an area in Brooklyn that is right under the concord's approach path to JFK. She always announced herself when she was coming in over us.",
"As well as the excellent points raised here, there was another issue. The Concorde was essentially hand-built with 1960s technology. There was a limited (and reducing) stock of spare parts available to keep them flying and a limited (and aging) group of mechanics who knew how to maintain them. Both British Airways and Air France knew that they couldn't keep Concorde flying forever and there were strong rumours that BA at least was seriously looking at shutting down Concorde operations even before the Air France crash. That just sealed the deal."
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60ahgf | Despite both being highly totalitarian, how are Nazi Germany and Soviet Russia polar opposites in political ideology? | Nazi Germany was far-right and Soviet Russia was far-left. Despite this, both were highly oppressive, totalitarian dictatorships. What made their ideologies so unable to get along with? | Repost | explainlikeimfive | {
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"Nazism was a nationalist movement, meaning that they were all about the (mythic, idealized) German people and German state. They were all about taking care of the German people first (and, obviously, horrible anti-Semitism and racism and so on) because they believed that Germany in particular was better than everybody else. Meanwhile, the ultimate goal of Communism is a stateless society where the working class owns the factories and stuff and there's no need for top-down control. In this philosophy, the Soviet Union was actually an intermediate stage-- basically, \"we're going to control everything until you guys realize how great Communism is and rise up to overthrow all the other governments.\" (Obviously the USSR in practice would probably not have given up control at some future point, but that was the justification for its totalitarian governance.) So Nazism says \"GERMANY IS THE BEST NATION AND THE GERMAN PEOPLE ARE THE BEST\" and Communism says \"NO MORE NATIONS, ALL PEOPLE ARE EQUAL.\" Boom, ideological clash.",
"In both ideologies, the problematic elements arise from the notion that the group is superior to the individual. In classic Enlightenment philosophy, the group exists only to serve the needs of the individual within that group. Thus the group's actions must be morally reflective of the individuals within that group. In contrast, Nazism and Communism claim the group itself is paramount and the individual must be subordinate to it - and the only morality is the needs of the group. As a result, both doctrines tend to reject all moral restraint so long as it can be argued that the group benefits. However, they differ in terms of how they define the group. With Communism, your group is an ideology. Communism is based on the notion that Marxism is a scientific doctrine explaining all of history, economics and politics. Anyone who doesn't accept this doctrine is clearly wrong and must be educated/exploited/eliminated. However, as long as someone accepts your doctrine, they can be a member of the group. This is roughly similar to how Islam spread - you conquer people and make their lives miserable until they convert to Islam. In contrast, Nazis viewed the group as ethnic/racial group. Their scientific basis was eugenics, where inferior races should either be subordinate to superior races or eliminated entirely. Since you can't educate away racial inferiority, that really means your only solution is to exploit them for labor until you can rid the world of them. These different categorizations of the 'in-group' meant that Nazis and Communists couldn't really get along.",
"Nazi ideology was not merely at odds with Soviet ideology; it was created in direct and hateful opposition to Marxism and all Slavic people (which includes most of the Soviet population.) Hitler spoke of Marxism and Judaism as the world's two evils, considered Slavs to be barely human and Soviet Communists to be puppets of powerful Jews, and spoke of a need for Germany to expand east and displace/destroy them. Promptly after taking power, he began to suppress Communism in Germany and issue anti-Soviet propaganda. He overtly hated the Soviets and wasn't subtle about it. As for the Soviets, they had some interest in closer ties, but until 1939 their top-ranking diplomat was Jewish and therefore rejected by Nazi leadership.",
"I feel like everyone isn't getting it. From a purely ideological standpoint, Naziism and communism are complete opposites. From a \"apply ideals to real life\" standpoint they are the same because the human element is the same literally everywhere you go. **Eli5 of difference:** Communists view everyone as equal - socially as well as economically. Nazis view one group as absolutely superior to others. If those two ideas aren't opposites then I don't know what is. Also do try to remember that communism sprang from Marxism. Karl Marx was a German Jew. Hitler hated Jews, remember?"
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60bnon | Why can't we build a type of plane that can fly out of the atmosphere and into outer space instead of using rockets? | I understand the space shuttle is kind of like that but why do we not have something that can take off, go into space, and come back and land no problem all on its own? I feel like using rockets to get shit into orbit is a little Overkill and primitive. For instance the sr71 Blackbird reached the edge of Earths atmosphere why couldn't it just keep going until it is in orbit? | Repost | explainlikeimfive | {
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"Planes fly by forcing air over their wings to create lift. They use engines to make the plane go forward and the forward speed causes the air to push up on the wings which counteracts gravity. There is not any air in space. So wings are useless. The only way to make yourself go forward is to throw a bunch of stuff away behind you. Which is what a rocket does.",
"Jet engines require oxygen to combust with fuel and air flowing around the wings to create lift. In the upper atmosphere you run out of both of those things and so the plane simply cannot climb any higher. Now, you could still escape gravity with a rocket, but then you can just build a rocket - like the one the space shuttle is strapped to on takeoff.",
"As you go up, air pressure goes down. This means air-breathing engines lose their oxidizer, and you have nothing for the wings to lift up against. Some kinds of specialized super-aircraft such as the SR-71 that compensate for this by going extremely fast. There are potentially faster technologies such as [scramjets]( URL_0 ), but even as incredible as these could be, even at their fastest they can only reach half orbital speed. The rest of that speed can only be reached by rockets right now. Because that speed needs rockets, and rockets needs fuel, this means any scramjet plane or whatever needs to bring all that fuel with it all the way up. This makes designing such a plane awkward and very heavy. For example, the [Skylon project]( URL_1 ). Skylon short-circuits the problem by having engines which can switch between air-breathing and being pure rockets, but it will be a long time yet until such complex engines are working."
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60g3eb | Why fabrics go dark when they get wet | Repost | explainlikeimfive | {
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"Darker means there's less light reflected. Reflection occurs when light goes from one refractive index to another. As an example, air and glass have different indices, so you will see some reflection in a window. The bigger the difference in refractive indices, the more reflection there is. So when light goes from the air to the fabric, there's a big difference between the indices, so lots of reflection. Now add water. There's now a layer of water between the air and the fabric. Water has a refractive index between that of the fabric and the air, so there's less reflection. To break this down, when light reached the air/water boundary, the difference in indices is lower, so less reflection. Then when it meets the water/fabric the difference is again lower, so less reflection."
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60g86e | the concept of the dark web. I understand that you need certain software etc, but is it like the regular net? Do you just type in wed adresses, and is there a dark google or something? [Other] | Repost | explainlikeimfive | {
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"The dark web refers to anything that can not be gotten to by any common web search engine. This includes a lot of networks that is not connected to the regular Internet such as banking networks, government networks, medical networks, military networks, private home networks, etc. There is also a lot of big sites with not much interesting in them that the search engines do not bother indexing. There are tons of wikipedia clones out there that is just skipped by the search indexers. And what about URL_0 with its huge data storage that itself contain more data then is available on the rest of the \"white\" web? And then there is private storage hosting services like Dropbox and Google Drive. Everything is available on the Internet but not in a public fashion. This also include your private facebook images and your reddit DM messages. So the dark web is huge and contains a lot of things that is not easily available for a good reason. There is some sites that are hidden to avoid prosecution as their content would be illegal. Of course the common web search engines do not index these. One popular way to hide your identity is Tor Onion Router which is a project to help people stay anonymous online which is helping oppressed people around the world including in China, Libya and Russia. Of course they can not distinguish between people using the service for planning demonstrations against their oppressive governments and people who want to score some weed or even child prostitution. If you have a web site hosted on Tor you get a randomly chosen web address in the .onion domain. There is no search engine for it and it only composes a tiny portion of the dark web but this is where you usually find those websites that the creators do not want you to find."
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60gau1 | What is the physiological reason behind being "hangry," and why does it seem to affect women more than men? | Repost | explainlikeimfive | {
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"I have to carry around a secret stash of snacks for when my girlfriend starts snapping at me."
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60gqv3 | Does the NASA EM drive work? If so, how does it work? | Repost | explainlikeimfive | {
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"No one has proved it to work and no one has disproved it to work. The reported thrust could be explained by noise interference or the microwaves interacting with something on the quantum scale. We don't know, and the majority of the scientific community think it doesn't work because based on our understanding of science it really shouldn't work."
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60ixnv | National debt | Repost | explainlikeimfive | {
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"> I feel like if 82% of the work I did equated to debt I owed, I would be really struggling!? National debt and personal debt isn't the same. And *many* people have way more than 100% debt. When you get a mortgage, you're likely borrowing WAY more than 100% of your yearly income, especially if you're in a high cost of living area. Shit, even financing a new car can easily throw you over 50% debt. Countries borrow money to spend money, and as long as the return on that spending is higher than the interest, it's worth it."
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60jbyg | why do the majority of cartoon characters only have 4 fingers? | Repost | explainlikeimfive | {
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"Drawing hands are HARD. If you try to draw a hand and it's not perfect, it looks SO WRONG and distracting to people. Instead, they don't even try. Hell, they try hard to make the hands look fake (wrong number of fingers). This way it's so wrong it doesn't annoy people. It's like when robots are made to look as realistic as possible, but they just end up looking weird and creepy. But robot-looking computer bots made of metal look fine to us; they're so far away from looking like a person, we don't compare them to real people.",
"With many cartoons, all the features are simplified. Eyes become dots, hair becomes a few squiggles, etc. It would be incongruous for a character to have a simple face and very detailed hands, so losing fingers is one way to reduce detail. Unless you are looking, close, 4 and 5 fingers look about the same, while at three, you start getting crab people. Another way to do this is to draw mitten hands."
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60k2zz | Net neutrality | Repost | explainlikeimfive | {
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"Net Neutrality is the idea that all Internet traffic should have the same priority regardless of content. Its an unspoken agreement that ISPs wont throttle content from competitors while boosting content from their own sources. Comcast throttling Netflix to extort money is a prime example of the douchebaggery that Net Neutrality is meant to prevent."
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60mib5 | Why is it important not to fall unconscious after you suffer a concussion? | Repost | explainlikeimfive | {
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"It has nothing to do with consciousness affecting your recovery. It's all about them being able to ask you questions and observe your responses. If you're awake with your eyes open they can tell if your pupils dilate properly or if your speech is slurred or if you're even aware of your surroundings. These are all important tests to see how severe your concussion is. Without that, the only option is a brainscan.",
"Emergency doctor here (work in ED / A & E / ER depending on your locality). Just to add on a little to the previous answers which are mostly correct that, in short, it's not actually important to keep someone awake after a head injury. Everyone, especially children, can become quite sleepy after a good enough blow to the head. That, in itself, isn't a cause for concern. But we are looking at how rousable you are from that sleepiness amongst a list of other \"red flag\" symptoms and signs (such as vomiting or the more obviously neurological signs such as weakness or seizures). If, after a couple of hours, your natural state is still to drift off to sleep shortly after being roused - you've just earned yourself a CT head to look for signs of a significant head injury (e.g., bleeds). But if you were so sleepy that it took a reasonable amount of painful stimulus to wake you up then there would be no waiting and you'd be getting scanned straight away. So, again in summary, there's no benefit to remaining awake after a head injury - you won't suddenly drift in a coma because you wanted to rest your eyes for a moment... Instead, it's how easily you're woken or how long that sleepiness lasts for after the head injury that matters. Edit: I need to address one of my bugbears (... where on earth does that phrase come from?) which is in the current top answer: Pupil reflexes. If you have uneven pupils due to the effects of a head injury **you will not be conscious!** The cause of unilateral dilated pupils, in the context of head injury, is due to there being a significant enough rise in intracranial pressure - due to the presence of blood within the head - that it causes a 3rd nerve palsy. The other softer signs of significant head injury will already be present long before you blow a pupil.",
"Medical resident here: the major concern regarding head injuries is the potential presence for an epidural or subdural hematoma (a bleed above or under the dura mater that surrounds the brain). As we prefer not to perform a CT scan on every person who bumps his head, many people are sent home from the emergency department with instructions to have a family member wake the person every 1-4 hours to check his alertness and ability to orient to name, where he/she is, and what month it is. Any new confusion or increased difficulty waking a person up fully can indicate the presence of brain swelling or intracranial bleeds that may require neurosurgical intervention.",
"From an EMS standpoint, we don't want you napping on us because we want to be able to monitor your mental state. If your mental state becomes altered (you have trouble speaking, you think you're the President, etc), it gives us an indication that something likely isn't okay in your noggin. When a patient's mental state changes in a bad way, that upgrades your transport to high priority (if it isn't already high). Since EMTs have a limited scope of practice (we don't really have many tools available due to our level of training/certification), and we often don't have the manpower to accurately monitor your vital signs while we're packaging and moving you, keeping you awake and talking allows us to maintain a general idea of how things are doing in your body until we can get you to definitive care (a hospital). It's just one of the tools that we have in our pretty tiny toolbox. Realize that this isn't specific to head injuries---I prefer all of my patients to stay awake for the whole transport. As for what the doctors prefer in the ER, that's well outside of my swim lane.",
"My wife works in concussion research and the idea that you needed to keep someone awake after a head injury can actually be detrimental to their recovery. She says that if someone is falling unconscious that you should let them. If you overstimulate their brain with questions poking prodding and lights in their eyes you can only make it worse. The brain needs to rest same as if you injure another put of your body and falling unconscious is your brain's reflexive way of forcing itself to rest.",
"I think the myth about *keeping someone with a head injury awake because they might fall into a coma* has been debunked in recent years. They are perfectly fine to let them rest unless you need to keep asking them questions to judge their functions.",
"Subdural hematoma patient here. Ex pushed me and I fell. Hit the lower part of my skull (where it meets the spine) pretty hard on the edge of a metal framed glass topped patio table. Thought nothing of it (I've fallen over before on my own drunken accord... I was apparently 25 and indestructible). Two weeks later I'm immobilized in bed with serious migraines. Never had headaches before. Lost 20lbs in two weeks (win). Avoided the hospital for lack of medical coverage. Lost sense of taste. Lost sense of smell. Vision went DOUBLE. Saw two of everything and couldn't walk to my kitchen without banging into walls. Finally decided to go to the ER. Waited 7 hours. Saw dopeheads get meds before I was seen. Once finally admitted, explained symptoms... immediate CT scan. Brain surgery an hour later. Could've died. Still can't smell the scent of shit (yay?) and have limited peripheral vision four years later. Hit your head? Feel funny? SEE A FUCKING DOCTOR. Scariest experience of my life. Head trauma is no joke.",
"Please note that it is also important to actually get sleep after a concussion. Sleeping is a critical factor of recovery, and the closer to the incident you can sleep the better. Once you are done being questioned, and once you answer questions every once in a while, do NOT try to stay awake if tired. URL_0",
"Emergency medicine resident: most good points have been made, but there are some floridly incorrect points being spread here. Immediately after the injury, I care if you passed out when you hit your head or have amnesia for the 30 minutes prior to the event. This helps me risk stratify who needs a CT scan and who doesn't. This isn't us being frugal; if you CT scan every comer who has minor head trauma, you will eventually cause a tumor. En route, its good to keep assessing you to make sure your status hasn't changed. The classic presentation for an epidural hematoma (blood between the dura, a tight layer against the skull, and the skull) is a \"talk-die\" lesion; i.e. the patient briefly loses conciousnes, rouses and speaks, and then dies of rapid expansion. Once you've been assessed and observed and diagnosed with a concussion (i.e. too low risk to need a CT scan) and sent home, there is no need at all to be woken up. I do not advise my patients to have someone wake them when they are sleeping. I personally use the Canadian CT Head rule to stratify who needs a CT scan. Its been validated to rule out those scary bleeds, described above. You should be given \"return to the ED\" instructions on discharge that cover red flag symptoms. These are usually vomiting more than 2 times, severe pain despite NSAID's, or confusion.",
"This is actually a falsehood, in a way. They say that you shouldn't fall asleep if you have a subdural hematoma. Basically, if your brain is bleeding. If your brain is bleeding you can suffer all kinds of adverse effects, up to and including death. If you just have a concussion, it is unwise to stay awake. In fact, sleep is the best thing you can do to heal. Src: Had concussions.",
"That is no longer the suggestion for someone who suffered the concussion. We now know that during a concussion, there's a massive energy imbalance, where there's a huge \"surge\" of energy and nurtrients can't get into the cell fast enough for the brain to function like that. The best way to recover quickly is to limit the amount of neurons firing, which is what sleep does. The previous suggestion to them not falling asleep, is that they are worried about a hematoma forming. These hematoma's are what can be deadly, or seriously life altering in cases of concussion. There are two types of hematoma, one is subdural and one is epidural, which just describes what layer they are on (Dura matter is a lining around the brain, inside is the subdural and outside of it is epidural). Subdural is the one they are worried about, because the subdural layer contains the veins rather than arteries, which are on the epidural. Because of the way the veins work rather than the arteries, when a vein is ruptured it bleeds much more slowly, so in order to monitor the symptoms of someone, you need them to be awake (since there really isn't any tell tale signs of the injury when they're sleeping, unless they don't wake up). Epidural/Arterial Hematoma's will form much more quickly and you should see an effect soon after, rather than later that day, or even a few days later. But as everyone else has said, it's all about the ability to monitor symptoms and make sure you don't slip into a coma. It's fine to let someone sleep after a concussion, but the suggestion now is to check on them every half hour to an hour.",
"Because the symptoms of more serious problems cannot be observed while the person is not conscious, there may be serious brain damage which isnt obvious at first glance.",
"There has been mew information released that is perfectly ok to sleep with a concussion now. Once you do the initial checks like check pupils can dilate. If you are responding ok. Then you can go to sleep as this is when most of the healing occurs.",
"You're not supposed to go to sleep before you see a doctor, a concussion will make you sleepy. You could have bleeding on the brain, which could cause you to die. It's fine to sleep after going to the hospital and having your brain scanned and they find no bleeding.",
"Cave, extremely simplified answer. The reason why it's advised to regulary rouse kids and adults after head trauma is to make sure they are not getting increasingly somnolent (sleepy to the point of not bein rousable anymore), because that could indicate increaed intracranial pressure, brain bleeds etc., which could lead to death. If you had an uncomplicated concussion, you could sleep all you want - but since we don't know how severe your trauma is, we check. The sleeping afterwards is not what is dangerous, it is that you might miss an altered state of consciousness (think of someone awake who talks to you, then starts slurring speech as time goes by and drifts off, unrousable, to give an extreme example). TL;DR: If someone is sleeping/unconscious, it's harder to tell if the are just resting (yay!) or currently dying (nay!).",
"The immediate concern is that you have internal bleeding in your head. Going to sleep could mask blacking out due to pressure on the brain, which could lead to death. After a brain scan, the concern is considerably lower, so you are allowed to go to sleep in a monitored environment (I.e. hospital). They will continue to check on you in case of a slow bleed that had not been immediately evident.",
"By all technicality is better for we you to fall asleep if you feel tired. Staying awake actually has the potential to cause brain damage. However (and it's a big one), humans often require the assistance of other humans - particularly when they're injured. Being awake facilitates someone effectively monitoring your condition without needing something like a brain scan (which only a limited number of people can read anyway). Source: related to a Neuro-psychitrist"
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60n38g | The Higgs Boson and Higgs field | I've been trying to read up on them but I don't understand many of the physics words necessary. | Repost | explainlikeimfive | {
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"Basically, quantum field theory says that all particles are just fluctuations in a particle field. Imagine the ocean. Normally it is flat, but if you drop a rock into it it'll form ripples that travel outwards. Particle fields act the same. F.ex the electromagnetic field is usually pretty smooth. But if you poke it hard enough it'll start to ripple. Those ripples look like particles to us, in this specific case photons. Every particle has an associated particle field. So an electron is a disruption in the electron field. An up quark is a disruption in the up quark field etc. So that explains the relation between the Higgs field and the Higgs boson. The Higgs field is just another particle field and the Higgs boson is a disruption in that field. So why is the Higgs boson such a big deal? There are dozens of particles, what makes the Higgs boson so special? The answer to that is mass. What is mass anyway? Mass is just a resistance to acceleration. If I try to push a car it won't instantly zip away at the speed of light, it will slowly start rolling, providing counterforce as long as I try to accelerate it. Einstein has shown us with E=mc^2 that mass is just confined energy. Say I have a massless box lined with perfect mirrors. Say I release a photon in the box. If I now try to push that box the photon will get redshifted on the far side and blueshifted on the near side. Since photons do have momentum, this causes the photon to push harder on the near side than the far side. The box is suddenly pushing against me. The box suddenly acts as if it has mass, while it is entirely made out of massless particles! Turns out that all mass is just an emergent behavior of massless particles interacting with other massless particles. You are a lot like that box of photons: Just a whole load of massless bits interacting to give the illusion of mass. This works very well for every composite particle. The protons and neutrons in atomic nuclei get 99% of their mass from tossing gluons between their constituent quarks. However, there was a problem: That remaining 1%. Certain particles have mass, even if they're all alone and not interacting with anything. For example, electrons have mass, but as far as we're aware they aren't made of any smaller particles. This is where the Higgs field comes in. The idea was that Electrons, quarks and other particles have mass because they're constantly interacting with the Higgs field. They're constantly dumping and stealing something called Weak Hypercharge from the Higgs field, and due to those interactions they have mass. This was theorized back in the 1960's. But theories mean jack shit without evidence. So how do you detect if a particle field exists? By detecting the particle of course. So this is what happened in 2012. They used the LHC to give the Higgs field such a large whack that it produced a Higgs particle. That Higgs particle quickly decayed, but scientists managed to measure the resulting debris, thus showing that the Higgs field is real and explaining why particles have mass."
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60n59k | How does inbreeding cause so many issues? | Repost | explainlikeimfive | {
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"The reason are so called \"recessive genetic disorders\". Those are genetic diseases which only express themselves when you have two copies of the defective gene. If there's only one of them, they may have a reduced effect, no effect at all or even a benefit in some cases. Because of this, it is necessary that both the father and the mother carry the defective gene. So if 1% of all people carry the defective gene, only 1%\\*1%= 0.01% of all couples both carry it, and therefore could have diseased children. 1/4 of their children would suffer from the disease, which is a total of 0.0025% of all children. However, siblings and other closely related people are much more like to have inherited that gene. For example, if one parent has it, each child has a 1/2 chance of carrying the defective gene, so two of them would have a 1/4 chance of both carrying the gene. So the chance of having that same disease among siblings would be 0.25%, 100 times more likely. So in short: Children of closely related parents are far more likely to have one of these recessive genetic diseases, many of which are incredibly rare otherwise."
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60nb1e | How does something like Alzheimer's lead to death? | Repost | explainlikeimfive | {
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"The disease itself doesn't directly cause death, however it slowly causes the affected person to lose the ability to take care of themselves - they lose motor functions and the ability to speak, and end up spending their days bedridden, which also results in lack of proper diet and weakening of the immune system. They usually die from something like infections caused by pressure ulcers or pneumonia."
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60obl8 | Why do countries around the world have different outlets? Why couldn't we have decided on one before? | Repost | explainlikeimfive | {
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"I'd like to refer to this XKCD comic: [Link]( URL_0 ) At this point it is too expensive to go through and redo the outlets in different countries, which would lead into breakups of the industries and supply chains that make products internationally.",
"> Why couldn't we have decided on one before? Who is we? The United Nations or even the League of Nations before it existed long after Electricity became a thing. Plus even if they had the foresight for it there would be no consensus, the world would probably be split into two or three sockets surrounding the political divides of the time. Different countries have different outlets just because they do, each one came up with their own. Sometimes its practically pointless, the only difference between port and port is shape. Other times, countries will have differing amperage and voltages in their electrical grids, so plugging a device intended for one into the other is a good way to fry the device, so preventing the user from doing so until they get an adapter is a good thing.",
"Electricity predated portable devices and inexpensive travel. It didn't matter if the outlet in the UK and the US were different, because few people traveled, and those that did weren't bringing their 100 lb. radio cabinets with them. By the time more people were travelling with more devices, the different outlet types were too entrenched to change."
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60r6cq | How is the chip on a credit card more secure than the magnetic strip on the back? | Repost | explainlikeimfive | {
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"The mag strip is just the card information on the front stored in a magnetic medium for quick machine reading (swiping it just tells the reader card number, name, expiration, etc). OTOH the chip reader queries the chip with a challenge string which the chip encodes using a secret algorithm and sends back to the reader that forwards it to the bank system to verify.",
"[insert repost flair] The chip is designed to be much more difficult to clone, as it does not expose a static output. In order for a transaction to take place, the reader must establish two-way communication with the chip.",
"The chip is a miniature computer. There is a permanent storage, there is a CPU, there is a RAM memory to run a small application. When the chip is programmed at the factory, a public key of the bank is stored in the chip. This allows to perform [public-key cryptography]( URL_0 ). The chip knows it's communicating with the bank who issued this chip, and the bank knows it's communicating with authentic chip issued by them. The communication between them is encrypted. Reading storage on the chip is extremely difficult because the storage elements are just a few hundred atoms big (maybe even tens of atoms these days). You will probably need to spend tens of millions dollars to create a reading device (so that you can clone it). Compared to the chip magnetic stripe is a joke. You can get a stripe reader for a few hundreds of dollars and copy the information to a blank card."
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60rtlq | What happens when you get knocked out? | Repost | explainlikeimfive | {
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"The trauma from the brain bouncing around your skull basically overloads the neurotransmitters in your brain, making you go into a short-term paralysis. You then lose consciousness and your muscles relax. This isn't going into internal bleeding and many other things that can happen that can kill you."
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60svz7 | If a camera lens is a circle, then why is the picture a rectangle? | Repost | explainlikeimfive | {
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"text": [
"The lens is a circle but bends light so that it hits a rectangular sensor (digital) or rectangular film in the desired way"
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60vedh | How do scientists know that planets so many light years away, that are only blurs on our telescopes, have water and other such elements on them? | Repost | explainlikeimfive | {
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"It's called spectroscopy. Simply put, when light go through an element like hydrogen, the atoms will absorb different wavelength of the light. When you analyse the spectrum of light that when through hydrogen you will see a couple of black line where the wavelength were absorbed. It's a bit like the fingerprint of the element. URL_0 Here a few example of the ''finger print'' of different element. So if you look at the light from a star, that light was produce in the core of the star and had to go through the star atmosphere before reach us. So we can see which ''finger print'' of element we see in the spectrum and determine which element there is in the atmopshere of the star and what percentage of each there is. For a planet, the light emitted by their star went through their atmopshere, bounced on the ground, went through the atmosphere again and then reached us. So we can see what elements that light went through.",
"They looked at a spectrum of light and saw water absorption lines. URL_0",
"the netflix show cosmos goes over this too. i recommend everyone watch it. basically explains a bunch of science and what not."
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60z6b0 | What exactly is clean coal? | Repost | explainlikeimfive | {
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"The term \"clean coal\" is a myth brought about by the coal industry's public relations team and really the correct term is coal pollution mitigation. There is no such thing as clean coal. Coal is the dirtiest of the energy production fuels and there is no way to really use coal in a clean fashion, but there are ways to mitigate the pollution. However, all methods essentially swap one pollutant for another pollutant so the trade off is marginal. There are a number of different methods, but none of them have proven to either be successful for large scale use or they are just so expensive that they are economically unfeasible. Do date, no \"clean coal\" energy source is in use. Clean coal is an oxymoron that is purely sold to the public for political purposes.",
"Coal burning that uses special converters to make the byproduct less harmful for the environment but still more harmful then most other energy sources. URL_0"
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60z6qk | Why can some people feel storms approaching in their hips, knees or other joints? | Repost | explainlikeimfive | {
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"The air in our atmosphere is constantly pushing down on us, although this pressure does vary all the time. This is called barometric pressure. Low pressure in the atmosphere tends to have storms that come with them ( why that is, is meteorological and some one could expand on that). When low pressure \"fronts\" come ( and the storm) the pressure against your body drops as well, and your joints and areas that are injured or are old can begin to swell/ inflamed and \"ache\". I broke my tibia (lower leg bone) from a motorcycle accident and my knee from the accident tends to act up when storms come. Just like anything else in life it's not a 100% accurate measurement though. Edit: spelling and grammer.",
"I want to add to your question. I can feel storms coming in some joints but only the ones I've broken. What makes the broken and healed joints different than the ones that have never been broken"
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60zi2l | What are the bright dots you see sometimes when rubbing your eyes? | Repost | explainlikeimfive | {
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"text": [
"It is called phosphene. it is an illusion that is caused by manually stimulating the cells of the eye. For more checkout this Wikipedia article URL_0"
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612fuh | Why do we see colours when we push our eyes? | Repost | explainlikeimfive | {
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"The receptors in your eyes are normally stimulated by light, but that's not the only thing that can stimulate them. Electrical activity and pressure, for instance, can also do so. So when you push on your eyes, you exert pressure against those receptors, which causes them to send signals to the brain. The brain is ignorant of the *cause* of the stimulation, it just says \"Hey I got information from the color guys\" and so it paints you a picture based on the signals.",
"Could someone apply a pattern of pressure to create distinct images?"
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613380 | What Happens on a Molecular Level When Two Things Touch? | Repost | explainlikeimfive | {
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"The atoms of your finger have electrons around their nucleus. When you push down on a keyboard key with your fingertip, then electrons in the tip of your finger get really close to the electrons in the plastic atoms on the top of the key. Since electrons repel each other, eventually your electrons are pushing away the key's electrons enough that the key moves. That's how you type. I call that contact, but it's not exactly the same."
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6145x5 | Space Time. | Repost | explainlikeimfive | {
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"Up until Einstein people followed **Newton**s concept of an \"absolute time\". This means while there might be different timezones (since we just arbitrarily set them a couple of hundred years ago), one hour for you would have the same lenght as one hour for me, **independent** of where we are or how fast we move (or anything else). What **Einstein realized** was that **time and space are** actually not separate concepts but **linked**, this is what we call spacetime and is at the center of the theory of relativity. In most cases the reciprocal influence between what we call space and time is small, which is why we get away with ignoring it in our day-to-day-lives (unless you are an astronomer or work with GPS or so). It's like saying the surface of a lake or sea is flat - while we know that the earth is round and it thus has a tiny tiny curvature, but this curvature won't matter much to you (or me). When you move faster (close to the speed of light) or are near really, really heavy objects (black holes for example) the interactions between space and time however become larger and larger. This all starts being a (tiny) bit more intuitive if you think of time as just another dimension (in addition to the 3 spatial ones) and then use \"standard matrix calculus\" to transform coordinates from one reference system to another (but for this to really apply to someone that person needs to have an understanding of maths at a college/university level, so not exactly ELI5) **Highly simplified:** - being near large masses makes you age faster (astronauts age about 0.01 second per year less than people on earth) - moving faster makes you age slower (flying in planes around the world makes you age about the fifth millionth part of a second less....so not really worth it) - the thing that \"connects\" space and time is the speed of light (c) which is the upper limit for the speed anything can achieve, independent of reference system. This means that - counterintuitive, I know - if you send out 2 lightbeams into opposite directions and then \"look\" from one of the beams at the other (make it your reference system), it will still only move away from you with the speed of light (and not twice as fast). - This is also kind of the reason the equation E = mc² is so famous, as it illustrates that connection. PS: I'm a physics graduate, but I fear my professors would probably murder me for butchering the concepts like this. still, general idea should be fine and I hope somewhat understandable. edit: formating/highlighting"
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617d3d | Why were prehistoric creatures so much larger than creatures of today? | Repost | explainlikeimfive | {
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"There are a couple of theories. In the Paleozoic Era, there seems to have been more oxygen in the air which allowed for massive insects. Being larger also can have evolutionary advantages. Larger animals are harder to predate. But as a result, the predators also grow bigger. A third theory is that shifts in temperature has some effect on size, as temperature has an effect on metabolism."
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617nu8 | How a conventional battery stores power. | Repost | explainlikeimfive | {
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"Technically the batteries don't store electricity, if you pull them apart you won't find it, they produce it as the result of chemical reaction happening in them. It doesn't release all at once because chemical reaction happen relatively slowly. Capacitors are the things that can store electricity and can release it at once. In non-rechargeable batteries the reaction happens once, and once it's out of reagents it produces nothing more, in rechargeable batteries the reaction can be reversed through electrolysis if you add electricity to it.",
"*TL;DR:* **Because nature allows us to change one form of energy into others, batteries allow us to store electrical energy in the form of certain chemicals, and we can cause those chemicals to convert that energy back into electricity in a controlled way.** Electricity is a form of energy, kind of like heat and light are forms of energy. All of those things can be stored up in certain chemicals. A great example is a tree: when it grows, it \"stores up\" chemical energy by turning sunlight and water and air into wood. We can then burn the wood from that tree, and it releases that chemical energy, a whole lot faster, in the form of heat and light. But it doesn't *instantly* release 100% of that energy, the process takes time because the chemicals take time to meet and react to each other since wood chunks are very large and not every bit of them is exposed to lots and lots of air. Batteries, pretty much the same thing, but they are built to convert their chemicals to electricity instead, and you can then convert that electrical energy into heat, light or movement depending on how you apply it. Batteries store up that chemical energy in two ways. The first way allows for a lot of energy storage but unfortunately is a one-way process - once it's drained, you can't feed energy back in and recreate the battery's original chemistry, kind of like how burning wood makes that wood go away. The second way allows you to feed energy back in and create the battery's original chemistry. This requires more engineering and is tougher to build though, so rechargeable batteries are more expensive. And in the same way the wood doesn't just explode into energy instantly, the battery's construction regulates the speed at which it converts the chemical energy inside it into electricity."
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618qhj | Why are galaxies relatively flat as opposed to being spherical? | I took a look at [this post]( URL_0 ) and noticed every galaxy I see are always generally flat and not spherical, why is that? Please remember I'm 5. Edit : front page? ok | Repost | explainlikeimfive | {
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"From [Previous thread]( URL_0 ) - Here is a great ELI5 explanation. > Have you ever seen pizza made from scratch? The dough begins as a ball. It is then thrown in the air and spun. As it spins, the dough flattens and moves outwards into a disc shape. Solar systems and galaxies form like that. > Because they spin. When you have loosely connected matter, like the dust from which galaxies are formed--or, say, pizza dough--as it rotates, it tends to push material away from the axis of rotation. Thus, gravity can compress the matter into a disc-like shape, but the faster it rotates, the harder it is for it to compress into a spherical shape. > This applies to the formation of many objects in astrophysics--it's why solar systems tend to have a 'plane' much like galaxies, and even stars are originally formed from a collapsing disk. > It's also worth noting that there are more spherical galaxies, as well as a large central bulge in otherwise 'flat' galaxies. There's quite a lot of variance.",
"As kind of an addendum to this question, is it possible for a disc shaped planet or star to exist? Or is it not possible for one to spin fast enough to achieve the effect? Is a pulsar the closest you can get to this?",
"If you have a large clump of particles swirling around randomly, there is generally a direction of rotation that the whole clump is spinning in. As for why its flat; generally, while the whole is spinning, the up and down motion tends to cancel out as particles crash into each other with the spin persisting. The result is a spinning flat disk that many galaxies this video describes it better than i ever could URL_0",
"So the main thing at work here is conservation of angular momentum, which is a fancy way of saying that the total amount of rotation in a closed (isolated, not connected to some other source or sink of energy) system has to stay the same. So say you have a huge cloud of dust that will one day be a galaxy. At the moment it's a huge blob with particles flying in all directions and bumping into each other. If you add up the trajectories of all of the particles in that cloud, you will end up with a net amount of rotation on one axis (in 3D space), which means that the whole cloud is rotating in some direction on some 2D plane. Since the total amount of angular momentum in an isolated system has to stay the same, that means that the cloud must rotate no matter how the forces inside it end up balancing out. Particles that aren't rotating in that direction continue to bump into each other, as well as rotating particles, and over time, all of those opposing directional forces cancel out, leaving the cloud more or less all rotating in the same direction, on that same flat plane. The reason the disc doesn't collapse into a sphere is because the particles are individually too light relative to their distance between each other to overcome the centripetal forces keeping them locked in their orbits. Planets form spheres rather than discs because the particles that make them up, while starting as a cloud and collapsing into a disc, are able to pull together into clumps gravitationally. They still keep rotating in the same direction, but they all become larger chunks with enough mass to maintain a 3D shape against the speed of their rotation. This is also why all of the planets in most solar systems orbit in the same direction, because all of the particles that made them did so as well, and had nowhere to dump that rotation.",
"Actually most galaxies aren't flat. The ones you know like andromeda and our own milky way, have a disk where most of the stars, planets, dust etc is but theres also a halo or sphere/oval shaped area around these galaxies which have less tightly packed dust, stars, star clusters, and planets. Theres also alot of rogue objects which arent really bound to anything gravitationally and are just drifting. The halo isn't really visible but there are objects that are a part of the galaxy out there. Then there are other types of galaxies which some don't even have a defined shape. Source: studied astronomy in college",
"If you have a lot of stuff rotating in random directions, then they tend to bump into each other a lot. The result is that stuff is either ejected or gets a change to its direction. Now, if you were to sum up all the stuff, *some* direction is going to have more stuff moving along it than the rest. The other directions will tend to cancel each other out, leaving you with the direction with the *most* stuff to be the remaining one.",
"Actually, there are several types of galaxies- Elliptical (Round), Spiral (The flat one in question), and undefined (no specified shape). The reason why spiral ones are flat are because systems of stars are an orbit, and therefore are going on usually the same path, which cannot happen in a spiral galaxy.",
"I've heard the term \"conservation of angular momentum.\" Can someone explain that? Or is that wrong?",
"Try spinning a mop around its axis, and see what the treads do. If a group of (celestial) bodies move in a way that implies a center of gravity between them, centripetal force will flatten the spinning collective. Minutephysics has a great vid on it. Don't have the link now. Anyone?",
"Additional question: Our solar system is usually represented in the popular media as flat, i.e. all planets (excluding Pluto) orbiting in the same plane. The exception is Pluto, which orbits in an angle (and having more of an elliptical than a near-circular orbit). Is that truthful? And if so, is that because of the same reason (i.e. like a pizza)?",
"Rotating things spread out. But also, there are lots of round and roundish galaxies. Ie: these are close neighbors to the Milky Way [Magellanic Clouds]( URL_0 )",
"Same reason pizza dough flattens out when they smash and spin it in the air! Centrifugal force from the spinning brings an outward force while spinning. It's a similar reason as to why a bicycle gets more stable the faster the wheels turn!",
"Things start spherical, rotating in all directions. Over astronomical timescales, things collide with eachother until they start to look flat. At this point, collisions are quite rare, so things continue to rotate in a relatively stable, flat shape.",
"short answer because you cant spin in every direction at once. long answer, You can only spin in a single direction at a time, even if you add other rotation vectors to the spin all that does is transform the original rotation vector (it changes the direction of the spin), this is why galaxies are planar disks instead of a spheroid blob",
"Any dust cloud in space has some kind of overall angular momentum about its centre of mass. This means that it has one \"amount of going-around-ness\" that it prefers. This is a conserved quantity, so no matter what happens inside the cloud the end result will have the same amount of going-round-ness Imagine that the final galaxy lies on a sheet of paper. Any vertical motion, through the page, starts off essentially random, but because of this lack of preference friction will eventually even it out. Think if two dust particles approach from above and below the page, their collision will nullify a lot of each particle's vertical motion but their motion around the surface of the page will be unaffected. Particles that are already moving in the on the surface of the page experience less bumps from other particles, so eventually it ends up where all the dust particles are going in a circle in the same direction around the surface of the page. Take away the page metaphor and you have a galaxy. This is also why our solar system is really flat, the same friction effects caused our primordial dust cloud to collapse into a ring around the sun from which our planets formed, that's why the planets all line up and orbit in the same direction."
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61ceyf | Gentrification | I recently stumbled onto this topic and have been largely confused by the controversy. I could easily see myself as a "Yuppie" moving into a poorer area to save money or to renovate a home. Why would this be a bad thing? | Repost | explainlikeimfive | {
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"It's taking a place that's isn't so nice and making it a more desirable place to live and hangout. They do this by commissioning artists to brighten the scenery, getting investors to start businesses such as restaurant or bars, adding parks for people to relax at, and driving out \"undesirables\" by either jacking up rent prices or hiring security to shoo away the homeless. It is looked down upon by some because it gives an area a commercialized and fake feeling. On top of that, it crowds the area with a bunch of \"yuppies\" whom some people find annoying. Also, I imagine people that lived there before gentrification would be angry about rising rent prices.",
"The knock against gentrification is that it often displaces people who have lived there longer, with lower incomes. Rents go up, Property taxes go up, and those with lower incomes can no longer afford to live there. While home owners who want to sell can benefit from increase property values, often they don't want to leave their friends, family and neighbors nearby, it may be close to their job, and lower cost housing may be in higher crime areas, etc.",
"Because it ends up pushing up property values, taxes, rates, etc. beyond what the current residents can afford. If someone rich moves into an area and does up the house, it increases the value of property in the area. It means more affluent people coming in and doing the same, further raising the prices and status of the area. Eventually it is no longer affordable for poorer people to live there so they end up displaced. And poor people need to be able to afford to live in houses."
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61do0h | How did all the water on earth today get here originally? | Repost | explainlikeimfive | {
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"We're not entirely sure, but there are two major theories: **1.** It has always been here and was integral to the formation of the planet. **2.** It arrived after the planet was formed, delivered by comets, asteroids, or other debris that was still flying around the solar system in the early years. The important thing to remember is that water molecules are abundant throughout the solar system, so the earth is not special by its presence alone. What makes Earth special is its size and distance from the sun that allows water to remain stable in a liquid state."
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61eqad | Why do we see a bunch of strange colors and shapes when we press up against our eyelids? | Repost | explainlikeimfive | {
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"It's not damaging at all. Your eyes are always trying to see, but when they're closed they don't have any visual stimulus - putting pressure on them by rubbing or pressing on them makes them think that there's something to see, so they're lighting up trying to process it. [Further reading]( URL_0 )",
"Similar question: With my eyes open, if I lightly press in the bottom left corner or one eye (pushing on the open lid not the eyeball) I see a black spot in the top right corner of my vision. Happens with the entire eye - any light press on one side = black spot on the other. Does anybody know about this? I asked my housemate a while ago but he said it doesn't happen to him.",
"Follow up. Why does this not happen when I close my eyes and press?... Just black, maybe a little white but that's when I'm not pressing."
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61etdz | Why cannot objects travel at or past the speed of light? | Also, what would happen if the object attempts to? | Repost | explainlikeimfive | {
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"Everything we say about science comes from a model - a group of theories that together describe the universe. We make observations, develop a model, use that model to make predictions, experiment and observe to confirm or disprove those predictions, and further refine the model. The best model we have for the universe is called Special Relativity. It makes many predictions that have been fully confirmed. It works like this. Time is just another direction, like length, breadth and depth are. Space and Time are really the same thing, so we call it 'spacetime'. Every item -literally everything - always travels through 'spacetime' at the speed of light. Particles without mass cannot travel through time, so must travel through space at the speed of light. Light is just such a massless particle, which is why it travels at that speed. Every item with mass - like a star, planet, person, coffee cup, dust mote or electron, can travel through space, if made to do so by some force. But it still travels through spacetime at the speed of light. This is why we experience time 'passing'. because we are forced to move through it. But the more we move through space, the less we move through time. It is like we are travelling diagonally through spacetime at a fixed speed. Eventually, if we are moving 'sideways' through space at nearly the speed of light, we practically stop moving through time. This is all very unexpected, and nothing like you'd expect from moving at more terrestrial speeds, but when we make things move very fast, we see just this happening."
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61f28r | How does code translate to circuits? | Repost | explainlikeimfive | {
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"If you take a stripped clean cpu architecture with no sophistication, it is loading an instruction from memory based on the instruction pointer value, and decoding that instruction to signals used to control the cpu circuitry. Then automatically advancing the instruction pointer to the next instruction. This is called the fetch–decode–execute cycle. One instruction could be decoded to what signal levels to send to hundreds of other places in the circuitry of the cpu. Signals control if registers should store the value on the bus, control if registers should put their value on a bus, what operation the ALU should use on input values. Control if the latest comparison flags should control the storing of values. And so on.. A loop is nothing else but the conditional write to the instruction pointer register. So a while loop in a high level language is some test instructions for the condition, and the condition outcome is stored in a condition register, then followed by the conditional write to the instruction register based on a bit in the conditions, if it should jump to the instruction after the while loop, or just continue into the while loop for another iteration until its end, where an unconditional jump goes up to the test instructions again. Types of variables is a high-level construct. In assembly language everything is bits in registers and loadable from memory. Assembly instructions use these values for specific purposes. It is perfectly possible to multiply a memory address with another value, but the result value is not useful. It is however useful to add a value to a pointer (to calculate the address of an element in an array). Many high-high languages zero-initialize variables instead of letting them have the value of whatever existed in the memory where it is allocated. However, a modern cpu has lots of sophistication to make it run faster, but they all maintain compatibility with the above model. A compiler writer or developer writing a tight loop in assembly can use understanding of the sophistication to get faster running code though."
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61f6we | Sleep paralysis. | Repost | explainlikeimfive | {
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"I'm not a scientist or doctor but I've had this since I was about 12, hundreds of times. When you go to sleep your brain stops communicating with your body to move/react so you do not react out on your dreams and potentially hurt yourself or those around you. Some sort of peripheral nervous system disconnection?? What happens is your mind wakes up without telling your body to. This can be terrifying and also include hallucinations. It has also been referred to as the old hag; an idea that some witch or demon is sitting on you and sucking your life away. When this happens I still sometimes get scared but most of the time I recognize what is happening and calmly pull myself out of it. If this happens to you and you're scared, focus on moving something such as a finger and once you're able to it will immediately stop in most cases.",
"When you sleep your body releases chemicals that paralyzes you to prevent you from acting out your dreams. That is completely normal. However under certain conditions it is possible to be awake, or wake up while this is happening without the paralysis ending immediately, which is not normal. Some things that are known to increase to the risk of it happening are lack of sleep, irregular sleeping patterns and sleeping on your back. If it happens to you and you want to get out of the paralysis faster, here are some things that have worked for me: Being aware what is going on and not panicking. Focusing on wiggling toes and/or fingers. Don't be scared of the old hag, it's just a hallucination. Focusing on breathing or trying to breathe fast.",
"Body thinks its asleep But you see things In real life But you're still dreaming So your mind makes you see/hear/feels things"
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61gs3c | Why do paper cuts on fingers hurt so much, even though they're relatively small? | Repost | explainlikeimfive | {
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"Paper isn't sharp, it's ragged along the edge and just sort of rips it's way in rather than cutting. That's what makes it hurt, if you used a hack saw to cut yourself with it would hurt a hell of a lot more than a razor blade."
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61jxvx | Why do many people feel safer when they're in bed with the blankets pulled up, even though blankets provide no actual protection? | Not a judgement. I totally do this, too. I just don't understand it. | Repost | explainlikeimfive | {
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"Blankets with a particular level of weight activate pressure sensors in our skin. They tell us that we are \"covered\" and help with calming our hormonal responses. It's the same premise as \"thunder jackets\" for dogs. It's a calming sensation.",
"Because you're \"covered\". IT doesn't matter if it's a thin piece of cloth that wouldn't stop anything, it's better than \"nothing\" It's the animal instincts in our brain telling us that being \"hidden\" is superior to not being hidden, and helps us feel better, even if the coverage is useless at anything but warmth.",
"It doesn't provide physical protection, but you are still hidden and out of sight. Of course anyone can see when someone is under a blanket, but it might not be so obvious for an animal for example. Its just an instinct to hide when in a dangerous situation.",
"I'm not sure on the scientific research behind this, but this is the theory I have heard. The idea is that it triggers the same sensation in the body as if we are being hugged. In social animals, a sense of security/safeness is primarily attained (especially in the younger years) by physical proximity to others in the pack (hugging or touching). It triggers the attachment system, which is basically our \"cool down\" system. There are different groups of 'happy' or 'pleasant' emotions. There are the stimulating ones (excitement, accomplishment, pride), which feel good but also make us feel more energetic rather than relaxed. All those \"uppers\" are the ones that motivate us to go out and *do*. And then there are the soothing ones that promote a sense of security (warmth, connection, belonging, togetherness - which are all to do with our social needs and generally promote a 'relaxed' sense of being rather than an energetic sense of being). So we rely on this affiliation system to calm down and relax - these are essentially our inbuilt \"downers\". The reason we don't literally need other people around all the time as we grow (unlike as a young child) is because we internalise the sense that we have people behind us (as in others care about us) and use this felt sense of connection to soothe us. Therefore, simulating the sensation of being hugged triggers the 'calm down' emotions, as does hugging a pillow or a soft toy. Based on this theory there have been weighted blankets created for people with depression and anxiety as the extra pressure/sensation promotes better sleep and more of a sense of security. As I say, this is the theory I have heard but I am not a scientist and have no actual expertise, so if someone else knows this to be bullshit, please do let me know."
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61lni5 | Why do most products cost "X.99" units of currency, rather than simply round up? [Economics] | Repost | explainlikeimfive | {
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"Psychological pricing (also price ending, charm pricing) is a pricing/marketing strategy based on the theory that certain prices have a psychological impact. ... Thus, prices such as $1.99 are associated with spending $1 rather than $2."
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61pefr | The recent bill passed in America that allows personal browsing data to be sold. | Repost | explainlikeimfive | {
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"In 2016, the FCC set up new rules for ISPs which would have taken effect this year. Basically, these rules would require ISPs to actually ask you before they sell your information - called opting in. Currently, you have to find their contact form and actually tell them they're not allowed to share your information - opting out. The Senate bill just prevents those changes from taking effect. So as assholish as the Senate is being... technically, nothing changes. Here's a summary of what the new rules would be, [from ArsTechnica]( URL_0 ): > **Opt-in**: ISPs are required to obtain affirmative “opt-in” consent from consumers to use and share sensitive information. The rules specify categories of information that are considered sensitive, which include precise geo-location, financial information, health information, children’s information, Social Security numbers, Web browsing history, app usage history, and the content of communications. > **Opt-out**: ISPs would be allowed to use and share non-sensitive information unless a customer “opts-out.” All other individually identifiable customer information—for example, e-mail address or service tier information—would be considered non-sensitive, and the use and sharing of that information would be subject to opt-out consent, consistent with consumer expectations. > **Exceptions to consent requirements**: Customer consent is inferred for certain purposes specified in the statute, including the provision of broadband service or billing and collection. For the use of this information, no additional customer consent is required beyond the creation of the customer-ISP relationship."
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61pf8i | What would the consequences be if a United States President was Found to have Colluded with a Foreign Power for Election? | Repost | explainlikeimfive | {
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"Nothing. His party controls Congress and his voters don't care about that. Most likely, it will just be used to distract us from his dismantling of our safety nets and large give always to the rich."
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61phy6 | Why are most homeless people guys ? | Repost | explainlikeimfive | {
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"One contributing factor may be that women, especially women with children, tend to get some priority when it comes to shelters and housing programs.",
"Just as said previously, men are more prone to mental disorders. This has to do with genetics with the X and Y chromosomes. Ex. Color Blindness. The Y chromosome can't help deny the trait, so the X chromosome can freely cause the disorder. Meanwhile in women, the other X chromosome can help keep the gene recessive. Therefore in the end, disorders can be shown in men, more than women. It's just way more common to be recessive in females. Now that that's out of the way, Studies have shown that a majority of homeless people are usually struggling with some type of mental disorder. Usually, these homeless people are problematic in the fact that, some of them choose to be in their current state. Some of the mental disorders impacting the population is good ol' schizophrenia. This is probably not the best answer, but I think it's stable enough to go with."
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61piwj | Why is over the internet calls (VoIP, FB Messenger, etc.) audio quality still overall worse than that of cellphone calls? | Repost | explainlikeimfive | {
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"Have to disagree man. Most VOIP calls I make are better than ANY cell call. Maybe you have a better network? And Skype calls... those are now being used for livecasts on tv and radio because they're SO much better than cell or landline.",
"It depends on your internet connection. When you are calling with any of the examples you stated the sound quality depends on your internet speed and the internet speed of the person you're calling. If you 'just' call someone the quality depends on your connection to the provider. So if internet speed > connection with provider your internet calls will sound better than regular ones. (I am by no means an expert on this subject so i could very well be wrong, just seems like the logical explanation to me)"
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61puva | What do VPNs do, and why is it worth using one? | Repost | explainlikeimfive | {
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"VPN stands for Virtual Private Network. The most basic description is that another computer is acting as a *relay* for yours. This other computer can either be run by a VPN provider, or by a company you work for. When using VPN, all of the information coming and going out of your computer *doesn't* go straight to it's destination. Instead, it's encrypted and sent to the relay machine first, who *then* sends it on it's merry way to it's final destination. There's a few perks to this. * It means all traffic passing through your ISP is encrypted and they cannot read it. * This also applies to anyone who might be snooping the coffee shop wi-fi or any other stage along the journey, if they managed to get your data in transit they wouldn't get anything. * If the relay server is setup attached to a corporation's private network, then VPN users can acess the server and talk to other computers inside the building as if they too were on-site, even though they're not. This means they only need to poke one hole in their network. It's not perfect. If the VPN provider is compromised in some way you could get snooped, and if your own computer is compromised youcould get snooped. But it's a lot better than nothing, and in the corporate world is considered a normal seurity measure."
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61qc5u | How is it that lobbyists offering things to lawmakers doesn’t qualify as an illegal conflict of interest? | Repost | explainlikeimfive | {
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"Well, Timmy, it's ok because the lawmakers said it's totally ok and passed laws that say it's totally ok.",
"\"Buying votes\" is exactly what it is. Politicians are directly influenced by lobbyists which is why lobbying is despised. Corporations can bribe politicians through lobbying.",
"What? Buying votes? No... that's ridiculous. The lobbyists are just showing their support for senators, obviously the senators never let any donations affect how they vote."
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61s7mc | Why cant we fold any paper more than 8 times ? | Repost | explainlikeimfive | {
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"Little bit if physical and a little bit of math. Every fold doubles the number of layers that need to be folded while halving the size of the area to fold. 8 times is the same as 2^8 or 256 layers. If you start with a 1ft by 1ft sheet of paper, you would have 256 layers of paper with 0.046 square inches of folding space, or a 3 dimensional rectangular cuboid that is 0.046×0.046x0.99 inches. Interesting fact: if it were possible to fold a piece of paper 103 times, its thickness would be greater than the diameter of the known universe. Interesting facr 2: the record for folding paper in half the most is 12 times. This was done with 4000 feet of toilet (3/4ths of a mile)"
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61ustk | Before eyeglasses were a common product, how were people with poor vision able to cope with it? | Repost | explainlikeimfive | {
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"You don't need great vision to farm. Back when most people didn't get \"book learning\" it wasn't necessary to read so fairly poor eyesight wasn't a terrible hindrance.",
"Most people with glasses can still walk around without. Most people historically were farmers and didn't need to read. A magnifying glass could be used if you were a scholar and needed to read."
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61xuiw | Why can't price tags in the US include sales tax? | When I worked in retail back in the early/mid '90s, we would get constantly updated price tags based on regional sales and products. The POS terminals were connected to the same AS400 mainframe and the local tax rates were updated automatically. I've read many comments saying that it is too difficult to keep up with state and municipal sales tax changes, but it didn't seem to be an issue with the POS registers. That was 20+ years ago. Is there still a significant technological barrier or just corporate inertia? | Repost | explainlikeimfive | {
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"1) Some groups and people are exempt from some sales taxes. It is easier on the cashier if they do not have that tax already baked into the price. But this is less of a problem with computers. 2)This is a bigger one. Every city, county, and State has the right to put a sales tax on things. This means that it will be difficult to advertise things because you would have to have a different ad for virtually every single store location. That is extremely expensive for a company. 3) The biggest reason is that people are more likely to buy goods with the lower price on the shelf. By having taxes not included you make things look cheaper and psychologically people are more inclined to buy them. It is the same reasons things are price with 99 cents rather than rounding to the nearest dollar.",
"It has never been a technological barrier. However retailers want to announce the lowest price possible when customers are deciding on weather or not to buy something. If the price tag say $1.99 you might be more inclined to take it to the checkout then if it said $2.19. But this is not a good reason to prevent legislation for this so they present the argument that it is too difficult to keep up with the local regulation.",
"Most retail locations do not have digital price tags for their products and must print them every time there is a change in price. Paper is expensive and constantly reprinting signage for items that do not regularly change their price would be wasteful. Also, some signage is mass printed for all stores (think \"SPECIAL SALE!\" signage and such) that would be very expensive to print separately for each store's individual taxes."
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61ycyj | What is the fifth dimension like? | Repost | explainlikeimfive | {
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"Time is not exactly seen as a fourth spatial dimension. It's often used as a representation, but a classic example of a four-dimensional object would be the Tesseract, or Hypercube. It is basically not really imaginable for us how higher dimensions work, just like a two-dimensional object could not fathom a three-dimensional one. It would appear like a shape changing size when passing through the flat surface.",
"Don't know about the others, but the [5th dimension]( URL_0 ) is kinda R & B, pop/soul.",
"If we forget about theoretical physics for a moment and focus on the world as we've seen it up until Einstein(Newtonian physics, if that tells you anything), then the world is 3-dimensional. There is no 4th dimension, 5th dimension, or any such things. Just our 3 dimensions to move about. Now, it's also important to understand that we talk about world being 3-dimensional. Dimensions however aren't places. You can't travel there. There is no way you can travel to \"second dimension\" or \"third dimension\". 3-dimensionality just tells you that in our world, there are 3 directions you can go toward. How you decide which direction is which is up to you, the only thing that doesn't depend on your choice is the number 3. So \"fifth dimension\" looks exactly like \"third dimension\" looks like: Absolutely nothing sensible. What could look like something is \"5-dimensional world\", where you had 5 directions to go towards. Now, humans are bad at imagining directions that go beyond \"up/down, forward/backward, left/right\". Mathematically there is no problem at saying there is 4th dimension, but we have trouble visualizing it. Modern physics kinda claims that there are more dimensions, but that they're like, really small. It's not different from how string is sort of 1-dimensional if you look it from far enough, you can only go forwards and backwards on a string. But if you look reeeeeally close, you'll notice extra directions, you could go around that string, left, right, forward and backward, but that movement gets lost if you look from far away because there's so little room to move in those directions. Modern physics basically says that the world is like this, there are tiny dimensions that only allow very little movement about them, and we're too huge to notice that detail. Theory of relativity on the other hand claims time is 4th dimension, and it creates this concept of \"spacetime\". Time kinda starts looking like direction you can go towards in Einstein's theory, but it never quite becomes the same as other directions. I don't really understand it well enough to explain it. The point is: * Dimension is not a place * No one can quite imagine higher dimension visually * Dimensions higher than 3 aren't part of everyday experience * Modern physics uses higher dimensions in at least two different, contradicting ways",
"When you're writing down a bunch of properties of something, the number of properties is called the dimension. We usually think of a pack of cards as being 2-dimensional: (number, suit). We use two numbers (latitude, longitude) to specify a point on the surface of the earth, so the surface of the earth is 2-dimensional. The pixels on a computer screen have different amounts of red, green, and blue light, so the space of colors the screen can represent is 3-dimensional (R,G,B). An animated gif is six dimensional: you have to specify what the color is (RGB) at each position (x,y) and time (t). Sometimes physicists talk about how spacetime might have ten or 26 dimensions. In those models, the extra dimensions we don't see are \"curled up\": an animated gif has a time dimension that curls back on itself, since if the gif lasts for 5 seconds, then it's showing the same thing at t=6sec as at t=1sec. If you look at a garden hose from a long way off, it looks like a one-dimensional thing (how far along the hose?) but when you get up close, you can see the other dimension (what angle around the hose?). The curled-up dimensions are supposed to be around one Planck length long (the size of a proton to the size of a meter is the same as a Planck length to a proton)."
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61yg3k | How was the second invented | Repost | explainlikeimfive | {
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"A second is the *second* split of an hour, divided into sixtieths. First you have an hour, which you divide into sixty parts, the minutes, and dividing each of those parts into sixty new parts results in a second. The reason why its divided by 60 and not some other number like 10 is because the system has its roots in ancient civilization like the Babylonians, who used 60 as a base instead of 10 like we do. 60 might seem like a random number, but it isn't. It has very many divisors - 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30 and 60 itself. It makes for a pretty natural and sensible number base to play around with when it comes to math and commerce."
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61ygum | How do pronunciation characters work in dictionaries? | Repost | explainlikeimfive | {
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"The Oxford version uses the [International Phonetic Alphabet]( URL_0 ) which, while more complicated, is also more precise. For example, in the more 'layman friendly' URL_1 version, how is _per_ pronounced? Does it rhyme with _fur_, or _air_? The IPA symbol ə tells us precisely that it's a schwa, the kind of relaxed sound we'd use for comm_a_ or _a_-fraid."
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61ys7s | The year 2038 problem for computing systems? | Repost | explainlikeimfive | {
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"**Background information** Whenever you stored data in the computer system, you allocate a certain amount of space in memory for that. And you can't go over that space. There are physical limitations to memory. You have to buy it. And fifty years ago, it was **much** more expensive than it is now. (I paid $130 for a 128 **megabyte** hard drive around 1989. Imagine what you would have to spend to store all the names and demographics on a group of people for a university or government office.) Imagine that you're writing a database for a group of your friends that include Mary, John, Frank, and Lisa. Looking at your data you see that first names tend to be four or five characters long. Maybe you allocate a few extra characters in case you get some weirdo with a long name. So you set your first names field to be six characters. And then along comes Abraham and Roseanne. How do you store their data? **Historical Reference** Back in the 1970s, the Air Force set up a computing system for payroll. Back then memory was very expensive, so as much as possible was done to limit how much information was stored on the computer. Think about a personal check. A lot of information is already printed on the check. The stuff that stays the same: your banking information, your printed name, your address: that's all pre-printed on the check. The stuff that changes from check to check—the payee and amount—is the only thing that gets filled in. Businesses would have a form with as much information as possible already filled in. The computer would store and then generate only the information that changed. The Air Force actually printed \"197\" on their forms and only stored the final digit of the year. As 1980 approached, they realized they had a problem. They fixed the problem by adding another digit, DOUBLING the space they required for year data, but they made a very bad assumption. > Some programmer: \"You know, this problem is going to reoccur in 20 years.\" > Somebody with higher rank: \"There's no way we will still be using this software in 20 years.\" The problem was, it's actually much easier to add code modules to a large program to make it do new things than it is to rewrite an entire program from scratch. So as 1999 approached, people realized that their old two-digit date systems were still everywhere, and on January 1, 2000, it would look no different from January 1, 1900. **2038 Specifically** UNIX systems calculate dates based on the number of seconds since January 1, 1970. They store this information in binary in a 32-bit signed integer. The first digit is 0 if positive, 1 if negative. The rest of the 31 digits are a binary number 1,111,111,111,111,111,111,111,111,111,111 in binary is 2,147,483,647. That many seconds after midnight January 1, 1970 is exactly 3:14:07 UTC on Tuesday, 19 January 2038. At the next second, the counter goes to 10,000,000,000,000,000,000,000,000,000,000 and to computers all over the place (the Internet runs on UNIX) it will look like we are back in 1901. Systems are already being affected by this. The Congressional Budget Office can't run forecasts past 2037. How do you calculate interest payments on a 30-year loan after 2008? (Answer: on a Windows box.) So? We've got 21 years to solve this problem, right? **That's exactly how much time we had between the discovery of the Air Force payroll problem in 1979 and Y2K.**",
"Time on a computer commonly uses the starting date of the 1st of January 1970 at 00:00:00 UTC and is counted up in seconds. The time will be stored in memory as a 32-bit integer which means it can have 2^31 unique values or 2,147,483,647. If you try to add in anymore it causes issues sometimes the computer may crash or sometimes it may reset or other times weird things can happen. 2^31 seconds since 1/1/1970 00:00 is 19/1/2038 somewhere around 1pm UTC (Using the UK date format btw). How much can this effect? Pretty much everything electronic. The internet runs on databases that use SQL to get information, anything relating to time may break. Autopilot systems on plans need the time so they're at risk. GPS uses time to get your location so everything that uses a GPS has a potential to break. The solution is to move to 64 bit systems as soon as possible. Which we're already doing for other reasons so it's not something to panic about. This would give us 2^63 seconds of time. That might not sound a lot and you might be worried about this running out but that's not for another 290 billion years or so.",
"That's the time UNIX time rolls over signed 32bit integer storage capability. 32 bits just tells you how many binary digits you're using to write down a binary number. 32 digits. It's not unlike to having 2 decimal places to write down a number. After 01 comes 02. After 11 comes 12. But after 99 comes..? With computers, result is either an error, or 00. Year 2038 is when signed 32bit binary number used to indicate time and date rolls over its limits. Unix time itself is just the number of seconds that have passed since New Year's eve 00:00 of 1970. It's what most computer system use to indicate time and date."
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61zkyk | Why is 36.7 degrees celcius the perfect temperature for a shower, but 30 degree weather is too hot? (if you're Irish like me that is) | Repost | explainlikeimfive | {
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"You shower for maybe twenty minutes at a time, which is enough to warm your outer body temperature and it feels warm and comfortable but not enough time to hugely affect your internal temperature. If you spend too long in the hot water, you might notice how you'll start feeling tired and weak. That's because your body is overheating, and you might even feel a little dizzy if you overdid it too much. That's one of the very first signs of heatstroke, and if you stayed in hot temperatures too long you'd start seeing more serious signs too. But if you're outside, you're spending longer periods in hot weather and breathing in hot air, which itself raises your internal temperature faster. Your body will start sweating to cool itself down, which can leave you feeling dehydrated. This makes it harder for your body to cope with the stress of heat, and your body will start making you feel uncomfortable as one of the first warning signs to tell you to get to somewhere cooler."
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620vsf | Why do airlines price tickets at a remarkable increase close to takeoff (next day flights) when they know they're likely not to sell? | Repost | explainlikeimfive | {
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"text": [
"Those tickets actually do sell, because of reasonable market values. Air travel isn't about getting you to your cousin's wedding at the last minute. It is about business travelers. If there is million dollar business deal on the line, paying $1800 for a same day flight isn't that big a deal. In fact, those travelers expect those seats to be available, and are *happy* to pay that much, rather than not being able to travel. They consider it a valuable *feature* of air travel.",
"Many people who book last minute have urgent matters/business and are willing to pay whatever to get there. Often it's business travel, where the person booking isn't the one paying in the end. So the airline might be better off selling 1-2 expensive seats than filling all 8 remaining at rock bottom -- same revenue and less luggage, fewer people to board, less weight/fuel needed"
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622nd0 | What exactly is freemasonry? What do freemasons do? | Repost | explainlikeimfive | {
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"text": [
"It's just a fraternal club like the Elks or the Moose Lodge. They don't do anything creepy. They just keep their ceremonies secret. Sort of. There are a few documentaries that expose some of the ceremonies. If there was a conspiracy here then someone would have come forward just like all the people who left Scientology."
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623s29 | Why can't we just dump all our trash in molten lava to rid of it instead of having it seep and pollute the ground water while in the landfill? | Repost | explainlikeimfive | {
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"text": [
"The gasses released by burning the trash would be a huge pollutant. When the lava cooled, you'd still have rocks full of whatever didn't burn away."
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624liz | If the primary colors are red/blue/yellow, why is the RGB model so popular? | I'm just wondering what the difference is. If RBY are the primary colors, shouldn't they be the generic model that we use to distinguish colors? | Repost | explainlikeimfive | {
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"> If the primary colors are red/blue/yellow They're not. There are two methods of creating different colors from starting, \"base\" colors. There's additive color (combining different colors of light, where each new color adds more to the overall color, getting it closer to white), and subtractive color (combining different colors of pigment, where each new color removes some color, getting it closer to black). The primary additive colors are red, blue, and green. The primary subtractive colors are cyan, yellow, and magenta. The red, blue, yellow color model is outdated, and mainly used in art. But you can't actually produce every color from red, blue, and yellow pigment. For instance, those colors can never produce cyan or magenta.",
"They are a set of primary colors. There are many different sets, each of which can be combined to produce a different set of colors (called a gamut). RBY is easy to each kids, but isn't as dynamic as other sets. RGB is primarily used for additive color sources such as light. Added more colors adds wavelengths to the final color. You mix them all, you get white. RGB is used because it corresponds with how our eyes interpret color. CYMK (cyan, yellow, magenta, black) is commonly used for subtractive sources such as ink. They remove colors by absorbing wavelengths of light while reflecting others, so you mix them all you get darker colors. CYM are basically the opposite of RGB on the color wheel."
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62535k | Where did all these different American accents come from and when did they start to form? | For example, where the hell did a southern accent come from? What about a New York accent, a New Jersey accent? Since the colonists had British accents, why has the British accent not been retained all these years? Did it have anything to do with having Native Americans near, or are some American accents derived from Native American tongue? Is there a recorded time when these different accents began to appear, or when the erasure of the British accent in America occurred? | Repost | explainlikeimfive | {
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"The way people speak in Britain has changed *a lot* since Britain started colonising America. So those original colonists didn't have \"British accents\" as they are now. [Here's a video about how Shakespeare would have sounded back then]( URL_0 ;). So Americans didn't lose their British accents as such. Their accents just diverged from the accents in Britain. Some argue that a typical American accent is actually more similar to those old British accents than a typical modern British accent. Particularly in the way R is pronounced.",
"Many original colonists were British, but don't forget that America is the melting pot! For example, my great great several greats over grandfather came from Scotland in the 1600s and was part of the first ever group of pioneers to explore and settle in Tennessee (which to me is kinda cool!), those first settlers there were for the most part all Scottish. Different parts of the country were explored and pioneered by many types of cultural groups, bringing along not only their own languages and slang, but their own customs. This is most easily seen today in the Creole habits in Louisiana from French colonization (before the Louisiana purchase, it was owned by Napoleon) and the Mexican influences in the southwest such as Texas."
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625x93 | Classes and Objects in programming | Repost | explainlikeimfive | {
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"A class is essentially a description of *how* a thing should work. An object of a class is an actual working thing, that fits the description. Example: A car has four wheels, an engine and a chassis. Using the pedals, you can accelerate or stop the car. Using the steering wheel, you can turn the car. This is the *class Car*. The Audi A4 my dad has in his garage, fits the description of the class Car. It has four wheels, an engine, and he can use it to actually drive around. This is *an object of the class Car*.",
"Class = blueprint/plan Object = thing made from that blue print In programming creating an object from a class is known as construction. In C#/Java it would be something like this: var fordMondeo = new Car(); forMondeo is an object created from class Car.",
"you can define attributes(variables) and methods(functions) that belong together or are to be used together in a context. the definition itself is the class. if you create values based on that class you are creating an object. an object is to a class what a variable is to a datatype. example: classname: human Attributes: gender, age, haircolor methods: born, move, age the above is a very basic definition of the class human. an object to this class is an individual person that has its own gender, age and haircolor. the person is able to be created in the first place(born), able to move and able to age(change its' attribute age) it is also possible to create multiple different objects/persons that have different values to their attributes"
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6269fv | VPNs | Repost | explainlikeimfive | {
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"Virtual Private Network A system whereby you can connect to another computer over the internet via a secured 'tunnel'. This is different to connecting to a website or other computer via a simple SSL link as it creates a virtual network adapter on your PC and IP addresses are privately assigned to those adapters, thus making it a private network. When you connect this way, you could use a PC in Korea to connect to the internet, which in effect makes your PC in the UK or US look as though it is in Korea, since the Korean host is acting as a gateway to the internet for you. So your PC could be seen as creating a tunnel from the UK to Korea and emerging on the other side and accessing the internet or other resources there. Uses: - Being part of a big private corporate network - Pretending you are in another country when you want to access geo restricted resources - Totally secure file transfer between peers",
"So, when you send data it goes to your ISP, who read the instructions that come with the data and pass your data on to whoever you want to send it to. A VPN is a middle man. When using a VPN you lock your data in an encrypted bag with instructions on the outside saying 'send everything to my VPN server'. Your VPN server is the only one with the encryption key to read your data. Your VPN server will now unlock your encryption bag, take the data out, and send it to a different ISP along with the original instructions of where it should go. Good VPNs won't read your data when they do this. The key thing is that none of these bags are marked, and lots of other people are using your VPN server. That way as soon as your encryption bag enters the VPN server it gets mixed up with all the others and nobody knows where it came from, so nobody can trace the data back to you. Unless of course you leave some identifiable information inside the bag with the data, something that plugins like Java tend to do a lot. One thing to remember is that expert intelligence services will find ways to trace everything back to you if they have an interest in doing so. VPNs are not protection for doing wildly illegal stuff. But they will work against automated systems that log data traffic, public routers that are tracking what you are doing, and ISPs that want to sell your data off to advertisers.",
"Open internet: you and neighbor pal, Jimmie, each yell out from your respective bedroom windows to talk to each other. VPN: you and Jimmie run a single, physical, powered telephone system between your bedrooms. Obviously it's much more complicated but that's the ELI5 version.",
"First and foremost: Explaining VPNs in general is quite a difficult task, if my answer does not satisfy you, please clarify what you want explained about VPNs. General explanation: VPN means Virtual Private Network. What this means is that a VPN connection (whichever kind is used) will connect 2 seperate networks over a public medium (usually, the internet) so that it seems as if the networks were directly connected via a direct wire connection. There's a number of uses for technology like this, for example to link home office workers to the main office or to connect 2 different offices (Company HQ in City X with Remote Office in City Y). VPNs are necessary because these networks usually transmit sensitive information (client data, company secrets, ...) which should not be send via the public internet. There are different technologies to implement VPNs (IpSec and SSL) but explaining these and the differences between them would probably go beyond the scope of ELI5 and this question.",
"There are, however, some alternatives to VPNs, which can require fees to set up. There are the freely available Tor \"onion\" protocol and the Invisible Internet Protocol, or i2p, also known as the \"garlic\" protocol. i2p is easier to understand. All hosts connected to the garlic router network act as anonymous nodes. Your connection is doubly encrypted and your initial access point could be any garlic router in the network, and makes it appear that all of your packets originate from that IP address. Packets take random paths through the network to obscure their origin and destination. It is incredibly secure. Tor operates in a similar, but more complicated, manner. P2P sharing of network resources for the purpose of obscuring identifying information. I2p is more versatile as it supports all types of protocols including anonymous torrenting. Tor is strictly a hypertext system. Both protocols can be used to access the \"Dark Web\", which is not accessible by normal http/https methods. This region of the web contains everything from benign freedom of information and political interest sites, to more nefarious things like drug trafficking, arms dealing, even hitmen...contrary to popular belief though, most people simply want to browse anonymously an avoid the illegal sectors of the darknet.",
"Imagine two semi trucks driving down a highway One of them is an open, flat bed trailer hauling a farm tractor. The other truck is a walmart box trailer. Your internet connection with a vpn would be like the walmart box truck. You can see it moving (your internet traffic) but you don't know what's inside. iPhones? Clothes? Food? Who knows, only you do. Your internet connection with no vpn would be like the flat bed; anyone that looks at it can easily see what you're trafficking from where it started, to where it ends. But there's a little more. With a vpn it would be like If you wanted to move the truck from NY to FL...but the truck stops in Toronto first, switches contents to a completely different trailer, then heads off to fl. While you can still track where it came from, it will be much more difficult than a one way trip."
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629ed6 | Why cant we go faster than the speed of light? | Ignoring the "you need unlimited energy", what makes it that there comes a point where we just can't accelerate anymore? | Repost | explainlikeimfive | {
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"Even with unlimited/infinite energy it won't happen (though you can get quite close). When approaching the speed of light, more energy is converted into mass than is converted into increased speed, right up to the point at 0.999999(etc)c, all the additional energy would go into increasing mass instead of speed. There are two fundamental rules at play: Firstly that the speed of light is the upper limit of speed in the universe (otherwise causality would break down - you could see an event happen before it actually happened, for instance), and secondly that energy can't be created or destroyed. If you keep pumping energy into an object which is already travelling at 0.99999(etc)c, the object's energy increases, but its speed cannot. Kinetic energy is calculated as 1/2mv^2, and once v^2 is fixed (at ~c^2 ), the object's kinetic energy increase is converted to mass. Source: Am constantly travelling at circa 299,792,457m/s. Mass more than a large moon."
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62a9rt | Why is lobbyism normal in the US? What's the difference to corruption? | Repost | explainlikeimfive | {
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"Lobbying in its current state evolved from a more acceptable practice of simply getting advice from people knowledgable in a given field. For example: If you are trying to enact reform on law enforcement, a congressman who has little interaction with the police would have a hard time drafting legislation to address any of the prevalent problems. Therefore lobbyists would come to the Congressman to give their perspective. Activists from groups such as the NAACP or ACLU might give their opinion on the problems with how law enforcement currently affects people negatively, so he would know what problems need to be fixed. Representatives from the police union might give their opinion on the reasons officers act with the protocols they use. The congressman needs this kind of information to do their job effectively. The reason lobbying in it's current form is often thought of as pseudo-corruption is that the theoretical lobbying described above requires access to politicians and open communication. This is also more or less a given due to constitutional freedom of speech. Furthermore, it is somewhat of a necessity to have an organized media campaign and infrastructure if you want to run for office on a large scale, such as when running for a congressional district that expands far beyond your own city. As a result, most politicians need to spend money to campaign, and the law thus allows people to donate to politicians. While this may seem like it invites corruption, consider the alternative: The law cannot restrict an individual from spending their OWN money on a television ad to promote themself, due to freedom of speech. So if there was no mechanism for politicians to raise money, almost all large scale political campaigns would be inaccessible to anyone who was not privately wealthy or famous. Allowing fundraising makes it theoretically possible for anyone to run an effective campaign so long as they have supporters. The result of these two things: The open access of politicians to lobbyists as a necessity of the job, and the legality of fundraising as a necessity of campaigning, means that anyone can make their wishes known to politicians and can donate money to them if that politician ends up doing what they wish. From a technical perspective, there is a simple way to avoid corruption in the legally culpable sense: If you do not make an explicit or legally binding promise of payment as a result of a specific action on the politician's part, it is not a bribe. You are simply exercising your legal right to talk to your local government representative, and your legal right to donate money to that candidate. The loophole comes from the fact that even if your candidate fulfils their promise, there is no guarantee that you will actually pay them, despite your informal promise. Or inversely, if you donate to a candidate there is no guarantee that they will take the actions you desire. Without such a direct provable cause/effect, you can't definitively prove corruption. EDIT: To address the common responses in the comments: 1. I am not trying to advocate or condemn the current system. The question asked why lobbying isn't legally corruption, so I explained what the current system is and the reasoning for how it resulted, and did so in a neutral tone, but I don't make any claim as to whether this is a good or bad system. 2. Many bring up Publicly Funded Elections, where the government gives all candidates money to run. This already exists, to a degree. For example, any political party which achieves a certain threshold in a presidential election gets federal funding in the next cycle. The reason that this alone can't solve the problem is that the Constitution can't stop an individual from campaigning on their own money, so even with public funding a wealthy person is very advantages over a poor person. 3. As for WHY we can't block individual spending on a campaign, this was the interpretation of the supreme Court on the case of \"Buckley v Valeo\". Due to the wording of our constitution, such a law would be invalid here, Despite it being legal in some other countries. Obviously the Constitution can potentially be amended, but that's a broader conversation than I am focusing on with this comment.",
"Keep in mind that Lobbying is just talking to your representative, and you can be representing a group of people when you do it. You're informing a politician of your group's wants and needs. That's it. There doesn't need to be money involved. A few years ago, the US Supreme Court determined that restricting money = restricting speech (this is colloquially known as Citizens United if you want to see more info). Now, you still can't put money directly into these politicians' hands. But you can give it to a group that supports them (A Super PAC, which they can *almost* do whatever they want with the money. It's very flimsy, as far as regulations go). The practice of lobbying by itself isn't corrupt, but because money = speech in the eyes of the law, that allows for corruption to happen legally.",
"> Why is lobbyism normal in the US? First, you need to ask, what is lobbying? The 1st Amendment to the Constitution of the US says: > Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and **to petition the Government for a redress of grievances.** So, we all have the right to go into our local politician's office and be heard. If I want to go to the office of my House Rep, he has to hear what I have to say. It's my right to *petition*. Same goes for my city councilmember, mayor, State Rep, Governor, Senator, and even the President. They all have to hear what US citizens have to say. Now, as an example, let's say you want to see a Congressman. There are 435 Congressional Districts in the US, each representing populations of 711,000 people. Imagine the queue you'd have to make if everyone in the district wanted to *redress grievances* with their Congressman! So, to make things more efficient, people created companies that, when hired, would petition your politicians for you. This is called lobbying. This is why lobbying is legal, and population (and geographical) sizes is why it's normal. It's very hard for an American in Hawaii to visit their Representative in Washington. And it's very hard for 711,000 people to be heard all at the same time. > What's the difference between lobbying and corruption? Lobbying is associated with corruption because special interest groups would donate money to politicians who are open to their ideas. For example, let's say Congressman A is in favor of the oil industry, the oil industry lobbyists would be more willing to donate money to Congressman A's re-election campaign. In contrast, the solar industry lobby would not only abstain from donating to Congressman A's campaign, but they'd be more willing to donate to Congressman B's campaign, because Congressman B is a proponent of solar power as an alternative to oil! This looks like corruption because it appears that money is being exchanged for votes. But, can we prove that's the case? Or is it the case that these Congressmen already agreed with a particular position, and lobbyists are simply endorsing these candidates because they agree? The law makes a very clear distinction: if money is given in exchange for votes, then it's corruption. So, if you say to a candidate \"Vote for this bill and I'll give $500K\", that's corruption; it's a bribe. However, if the lobbyists says, \"Remember that bill we talked about the other day? I saw you voted the way we like. It is clear that your worldview and ours are compatible, and since we like you so much, here's $500 for your campaign\", then that's not corruption. It is perfectly legal. It's a fine line, to be sure, but the law has drawn the line there, and in that fashion. Right to petition is an important right for any free society to have. In the United States, congressmen have been investigated and arrested for bribery. In other words, the US *does* prosecute outright bribery. So lobbyists and politicians need to be very careful to not cross the line. The good news is that the line exists. The bad news is that many people disagree about where the line is currently drawn, and believe it should be drawn elsewhere.",
"What's so bizarre to me about most of the responses in this thread, is that 'in the US' has been consistently interpreted to contextualize intra-US politics. To be more specific, I was surprised that comparisons are not being made to other countries ie 'what does lobbying look like outside the US?' This is a fundamental question to ask, because many Americans don't realize that many countries around the world do not distinguish between lobbying and bribery. In fact, when US media outlets talk about bribery happening in other countries, the legalistic offenses often relate specifically to \"lobbying\" efforts. Read more cynically, the reason the US political system is thought not to have endemic corruption is because we have redefined what it means to be corrupt - not because we have uprooted corruption itself. **TLDR:** In many other countries, lobbying *is considered the same thing as* bribery. **EDIT:** A lot of replies appear to confound free speech and lobbying. There's a difference. I'm not trying to argue that actual free speech directed at politicians is necessarily lobbying. Ironically, this thread demonstrates why we have such issues in the first place around bribery. The courts in the US have exploited this to manipulate the definition of lobbying, political donations, etc (this is why we can't just say 'lobbying' in the US is the same thing as 'lobbying' in other countries). Funny how there was a Chomsky thread that hit the front page on the same day. *Actually, /u/BrotherPazzo explained this point much more concisely, so go check out his comment!* Also, most responses have referred to western democracies in their rebuttals - but see that's exactly my point. While there are western democracies that criminalize the equivalent of lobbying in the US, there are a great many countries (democratic ones!) outside the west that do the same. Apparently, we're not supposed to take their laws seriously.",
"Lobbyism is normal in the US because of the constitutional rights to freedom of speech and “petitioning the Government for a redress of grievances”. The eight largest lobbying groups in the US are US Chamber of Commerce National Association of Realtors American Medical Association General Electric American Hospital Association Pharmaceutical Research & Manufacturers of America Blue Cross/Blue Shield AARP Those cover a lot of people's interests, GE is 106,000 US employees alone",
"Way too complicated answers. It's normal because multi national corporations and the establishment have bought off the process, rigged the system and made it normal. What is the difference from corruption? Nothing, except that they don't call it corruption. In reality, it absolutely is, and until that system changes the U.S.will not be a democracy as much as it is a oligarchy, catering to the desires of the elite/establishment. See? No huge multi paragraph answers required, it's quite simple, really.",
"Lobbying doesnt even have to be immoral. If I start a petition that the government should do something about the heroin epidemic or other real problem, and pester congressmen about it, that's lobbying. Like most things humans do, its not the act itself, its the people involved who turn it slimy.",
"Americans should quit trying to rationalise what is clearly just a corrupt system in the eyes of the rest of the civilized world, where such practices are severely prohibited. It's the law of the rich, plain and simple. Democracy of the highest bidder kind.",
"As another comment mentioned, lobbying is just speaking to politicians about your needs and/or the way laws impact you. The problem is that people have very unequal access to politicians, and money greatly increases the chances you'll be able to have your voice heard (maybe literally). There are also concerns about direct bribes or more traditional forms of corruption in the process of lobbyists interacting with politicians. An example is simply eating a meal with a politician to talk-- who pays for that meal? I believe there are actually rules about that specific thing, but somebody will always believe they are too restrictive or not restrictive enough. And in general there are all sorts of opportunities for partnerships, payment, or gifts when your job is to hang out with politicians all day.",
"As an Italian lawyer, i can tell you that in the vast majority of cases it would be considered corruption in here. The objection is \"but it's not guaranteed the politician will actually do x\" would just make it attempted corruption (still a crime). I'll give you an example. Say a local group has an interest in the local administration to green light a project, something like modernizing a harbor, because they'll profit from it (construction companies, unions). They make sizeable above the board perfectly legal donations to candidates, that need that money to run for office in that administration. That's lobbying in the US and textbook corruption in Italy. You can try to rationalize it all you want, but the simple truth is that politician in the US need money to run for office, this is provided by donations. Now why would that person/ group donate again if the promises made don't get fullfilled. So you have a politician that needs to fullfill, or at the very least do his best to fullfill, the promises made to the donor, and the only difference with corruption is that you have a legalized system in place and a different name for it.",
"Paid speeches Campaign contributions Well paid non-executive board positions High paying corporate jobs after you've left office All of these are methods for washing bribe money. Many politicians who get these perks are taking them as payment for favourable legislation they have helped pass during their term in office.",
"It's not corruption because it's legal, and it's legal because the super rich like owning politicians. If you or I approached a senator and offered him $100 bill to vote a certain way, we would be engaging in bribery. But if we funnel $100k into his campaign accounts through a web of various entities, in order to obscure our involvement, then we hire the senator's nephew to an executive position which he has no qualifications for, that's lobbying.",
"I worked in a Maryland State legislature and was in charge of ethics in one of the representatives offices, which is indirectly tied with lobbying. Lobbying in itself is not an issue, tiny, community organizations do it all the time. Hell, paid lobbyists I've encountered were often quite frequently terrible, and ineffective, compared to local community organizations who often made quite convincing arguments about their issues. Problem is the Supreme Court ruling concluding that companies = people, and allowing these \"people\" to funnel unlimited amounts of money into politics. It is impossible to prove unspoken *quid pro quo* between business and politicians that happens because of this. As far as I can tell, that is mainly an issue on federal level, my experience with reps on state level was overwhelmingly positive, despite me being rather skeptical when I started there. At least in MD...",
"Lobbying in the US is similar to bribery. I think you should already know how it works. The lobbyist represent a person/group/company will talk to someone in congress and will persuade him to vote a certain way so that the person/group/company they represent will help him in the next re-election (they donate the money to his Super Pac, and they dont have to reveal who donated that money to you, until way after the election is over, and by then, nobody cares... Stephen Colbert does a great coverage of this when John Stewart was running Stephen's Super PAC). Its a system that its hard to change, why? Because money wins elections. You can hire smarter people, or more people, air more ads, etc, etc... And its a system that everyone in the government know is wrong but there is nothing they can do about it because they all need the money to keep going. Also because presidential campaign takes almost a fking year, and its getting earlier and earlier to get your name out, while other countries presidential election are rather short. The longer the election campaign, the more money you need.",
"I just heard this [this story]( URL_0 ) on NPR this morning about Professor Joseph Bankman. It's an interesting story of a man paying for his own lobbyist out of pocket to push \"no-brainer\" legislation, but going up against a corporation and California politics.",
"Imagine you have a playground (the country) with a bunch of different sections for playing (various business industries) that has a person in charge that makes decisions about the playground (the government). You love slides and go to the park everyday to play on them. However there are some rumors going around that the person in charge is planning on implementing a rule of \"no one can be higher than 10 feet off the ground\". This is because kids were playing on swings and were getting up too high than getting hurt. However you know that the slide and other toys are actually higher than 10 feet and so they will be affected by this new rule too. So you, the jungle gym kid, and the monkey bars kid get together and have a friend of yours (the lobbyist) go talk to the rule makers. This friend knows all about safety and which parts of the park that are high off the ground and so you trust him to talk to the rule maker about changing this bill. Your friend does this and gets the rule maker to make the rule now say \"No swinging higher than 10 feet off the ground\". So that it doesn't affect the other equipment. The part where corruption gets involved is imagine that the sandbox kid hears about the original rule and likes it because it will mean more people will play in the sandbox. So he gets a friend of his to give the rule maker some money if they keep the text of the rule the same no matter what anyone else says. TL:DR - A lobbyist is an informed friend of an industry who's goal is to work with the government so that they are aware of the specifics of the group they represent. Corruption starts getting involved when they begin offering money and job offers to get what they or their industry want.",
"In my opinion there is NO DIFFERENCE. Lobbying is the exact means by which the wealthy have taken over the US government, and I wish it could be severely limited. Unfortunately, the people with the power to impose limits on it are the very legislators whose political careers depend on it. Trump supporters on reddit have asked what he could do that would make haters change their minds about him. My answer: write an executive order severely restricting lobbyist access to members of Congress.",
"I don't get why they don't just have a government run standardized election channel. It would literally just tell you who's running and shit about elections. Each candidate would get the same amount of air time for ads or whatever with a rotation for prime time or something and so on to make it unbiased. Maybe more of an organization then a channel. The National Campaign Organization. Have check and balances and shit, would ideally separate corporations from politicians by changing how Campaigning and election coverage operates.",
"There will be many answers saying one is legal and the other isn't. They will also talk about how lobbying means you get your gov't rep's ear but not necessarily forcing that person into a specific decision. Those are in theory correct but that doesn't mean that it doesn't end up devolving into bribery. But in terms of why one is \"normal\" and viewed as acceptable and the other isn't, you can also look at it like this. Corruption is bribery for the benefit of a few. Lobbying is bribery for the benefit of a large interest group.",
"Don't let the United States of Ammendment fanboys fool you, there is no discernable difference between corruption, bribery and lobbying in the current US political system. The only reason it's not addressed as such is due to this developing slowly over time than being blown out in a scandal early on. Of course everyone has/should have the right to speak to their representative but any exchange of money for time/ideas/orders is a dictionairy definition of corruption.",
"Simply put, there is more than one type of lobbying. The main type we hear about is big corporate lobbying which is sometime accompanied with 'pay offs' to the politicians. However, there are also lobbyists for things such as Clean Water, Clean Energy, Social programs, ect. There are specific ways that the 'bad' lobbying occurs and rules that have to be followed. A good lobbyist will at least adhere to the rules. NPR just recently did a piece on this a few weekends ago with some previous lobbyists as guests. I tried to find it but failed sorry.",
"There are going to be a lot more nuanced answers here, but the gist of it is that people with a lot of capital can just use that capital to legitimize nearly anything they want to do as long as it doesn't step on the toes of other people with capital. The modern lobbying context grew from the fact that everyone with capital benefited from having near-exclusive access to politicians, so it became the new normal by virtue of everyone with money participating. It very different from corruption not because it has a different effect on the political landscape (it has the exact same effect on the political landscape), but because there are a few laws the people with capital agreed upon that enforce and justify the system. It's not a complete free-for-all, there is a particular process to it, but that's because even those who are functionally corrupt aren't complete savages and like a little nuance with their definitely-not-criminal activity. Also by having at least *some* laws on the books it helps them point to it anytime someone calls it out as bullshit. \"Hey, we aren't corrupt, we aren't breaking the laws we created!\"",
"Partial solution: no campaign advertising is allowed other than in a government provided booklet and .gov page available to all voters explaining your positions/ideals.",
"There is no difference, its legalized bribery because thats what corporations (and politicians) want. because more $$$ is better than less $$$ you dont need me to explain that one right? thought so.",
"lobbyism is the number one reason that democracy fails. for instance lawmakers are supposed to regulate finacial institutions and keep their power over society in check. how are they ever going to achieve that, if lawmakers are depended on finacial support from those finacial institutions they are to make regulatory laws for!? the media doesant get invited to back office deals! anything could be going on, anything could be standard practise!",
"Lobbying as an individual person, acting independently of any business interests is so rare. What its actually turned into is corporations (who are legally treated like an individual) and other PAC (political action committees) donating lots of money to politicians to get legislation passed in their favor. In my opinion, there is really no difference in how lobbying is actually being practiced in America right now and corruption. Somehow it is being allowed because they have found numerous loopholes to cover their asses in the event of a lawsuit or any other scrutinization.",
"Lobbyism wasn't always the norm. It is just the way civil society is structured these days. Before the 1960's, 'interest groups' (as you would call them) were composed of federations of people that worked together to advance their mutual interests in policy. During the civil rights movement, however, new more efficient strategies were invented to accomodate for the fewer resources and manpower among minority groups such as women and African Americans (because the federations were generally segregated). These strategies were much more efficient. Think the NAACP, an organization of 'experts' whose salaries are paid through donations. The problem is that these organizations were too efficient, and their use has spread considerably. More organizations are utilizing this rent-structure funded by grants from corporations and wealthy donors. The consequence is that these organizations disproportionately are at odds with the middle class and are more beholden to the wealthier segments of society. This is 'corruption' because it goes against the notion of popular jurisdiction by granting unfair advantages to a select elite."
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62btz2 | How can a VPN hide your browsing history from your ISP if all of the data still passes through their network to & from your computer, and they know exactly who they're supplying internet to? | I understand how it masks your IP from the rest of the web, but doesn't your ISP still know exactly who they're providing internet to? Data is still going through their lines to reach your computer. They know I subscribe to my internet service. I'm sure they also know my device's MAC address/other identifying information. | Repost | explainlikeimfive | {
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"Imagine that you want to send a note to your friend Sally, but she's too far away. So you have your friend Nosy Ned deliver it for you. Only problem is that Nosy Ned is, well, nosy. You know he's going to read your letter, and probably post it all over Facebook. So instead you write \"The narwhal bacons\" on a slip of paper and pay Nosy Ned to give it to George. And Ned reads it and thinks, \"WTF?\" Meanwhile, George receives the letter, looks up the code on his cheat sheet, and writes down, \"Meet me at the library.\" He delivers it to Sally, who writes a response: \"2 pm.\" George uses his cheat sheet again to encode the message as, \"at midnight,\" and gives it to Nosy Ned to return to you. Ned, of course, peeks, and again is like, \"WTF? Why are these two idiots talking about narwhals?\" Nosy Ned is your ISP, and George is your VPN. Everything that goes between you and the VPN is gibberish. Your ISP knows you are sending a coded message, but they can't read what it says. And everyone else only sees the massages George relays; they don't see you relaying it. Of course, you still have to trust your VPN is not selling your data.",
"A VPN will have an encrypted connection between the VPN server and the client. As a result, the only thing the ISP can see is that you are using a VPN, they must be able to read where to send the data to, therefore the IP address of the VPN server remains unencrypted, but the contents of the message is secure. During a normal web request like accessing reddit, it is similar, the connection itself is encrypted, but they know you are going to URL_0 since you are sending packets to reddit's servers. Once the VPN connection reaches the VPN, it is both a) probably in another ISP's network, therefore not something your ISP can access, and 2) unknown which VPN client is sending sending out which data since multiple VPN clients are connected to one VPN server and the ISP cannot tell which packets that go and access webpages and the general internet correlate to which of the VPN clients.",
"**Regular internet access** *Browser*: May I please get the website from URL_0 ? *ISP*: logs that customer A wants to go to URL_0 and then sends request to URL_0 *Reddit*: Oh, here ya go buddy! I'll encrypt it for you. *ISP*: Logs the fact that URL_0 sent encrypted data back to customer A and then sends them the data. *Browser*: Sweet here's the data from Reddit. **VPN** *Browser*: May I please get the website from URL_0 ? *VPN software on computer*: Sure *ISP*: cvape[rutcfe54ctujhf7te5yt98w745nc78yvb874gpm245j2hgu logs the fact that customer A sent some unknown encrypted data to the VPN *VPN*: Oh snap that dude wants URL_0 , Reddit may I please have? *Reddit: Hey VPN Server, here's the data from URL_0 let me encrypt that for you. *VPN*: Thanks Reddit! I'm gonna send this back to the guy. *ISP*: phc8f5yt04985yffg74358hf47383478cb4783gb & ^$%$* & T*G & gv logs the fact that VPN sent some unknown encrypted data to customer A *VPN software on computer*: Beep boop beep here's the data from URL_0 *Browser*: Here's URL_0 **So you see....** The difference is that with regular internet access, your ISP can see the websites you visit. With a VPN all they can see is that you are sending encrypted data to a VPN server and getting encrypted data back from the VPN server. Also the ISP that the VPN server uses sees a whole bunch of requests but they don't know who each request belongs to so they can't really package that data in a useful way."
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62d722 | So whats up with Congress and their browsing data.. why does everyone want to buy them? | Repost | explainlikeimfive | {
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"Congress were scumbags and sold out the us public. New law says your ISP can record and sell your browsing data. They want to buy congressmen browsing data to find gross or encriminating or dumb searches"
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62e3h9 | Why do you get heavier when you go "limp"? | Repost | explainlikeimfive | {
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"You don't. What makes it harder to lift someone when they go limp is basically about finding a good hand hold that provides a level lift. If you have to use extra strength to grip them, that's strength you can't use to lift them.",
"You don't get heavier, you get more unwieldly. By being a weight with a shifting center of gravity extra effort is required to keep the weight steady rather than sliding off to the side.",
"It's the same reason why you can't lift as much weight using barbells/dumbells as you can using a weight machine: you're forced to use stablizing muscles to balance the shifting center of mass, and therefore can't use as much strength to do the press/pull."
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62g9v1 | When our internet history becomes widely available for all to see, what actually links it to a person's identity? | Repost | explainlikeimfive | {
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"Well, it depends on where it becomes \"Widely available\" but I'll answer in all cases. Also, this is how *I* understand it. You use an ISP (Internet service provider). This is a company that connects you to a server your computer is trying to reach. In the process, your ISP may or may not record your public IP and what it's trying to connect to. This isn't *your* specific history, this is the history of essentially whatever your specific modem requests. Since multiple people could be connected to the same line that uses a single public IP, it's impossible to tell exactly who is requesting what. That could only be known by your router. Your router assigns each of its connection a private IP. It would normally be 192.168.num.num and is specifically for private networks. Your private IP cannot be seen by your ISP. So, the only entity that could have your internet history is your ISP *if* it's been logging what you visit. Some are more honest than others. Because even if you visit a website and type all of your information in, someone will know that *that* specific IP is you but they will only know that you visited *that* specific site. They don't know what other sites an IP has visited because that kind of information isn't exchanged between server and computer when you connect to a website. Google chrome or internet explorer knows since it records the sites you've visited. But even your ISP doesn't know since you're using a public IP and there may be multiple people using the same connection. Meaning, at most, they'll be spying on a group of people, not one specific person. Now a \"man in the middle\" attack is essentially the only reliable way of knowing what a specific person is visiting. It would also have to be based on your router. Essentially what they would have to do is connect to your router and \"sniff\" the packets that your private IP address is requesting (what your computer/phone/tablet is requesting). There's an easy way around this although not 100% fool proof. A VPN, virtual private network, or proxy. Essentially what this does is connect you to a VPN's server and request sites from there. Basically, the only thing someone spying on you would see is that you're sending requests and info to one address constantly, the VPN server. Usually, if it's a good VPN, this info is encrypted and only you and the VPN server can decrypt it. Your computer essentially asks the VPN server to connect you to whatever you're trying to reach. Be warned though that the VPN provider could be recording your history (I believe it's a law to do so in the UK). A good VPN could promise it won't but you can't really know. It's still good protection from essentially anyone who isn't very powerful, but you can never *know*. EDIT: A good VPN I use is CyberGhost 6. I believe you could use it for free or you could go premium. VPN providers need to pay property tax, maintenance, and electrical bills for their servers so normally a good VPN is one that you pay for. Not one that is influenced by who it advertises since the only other way a free VPN could pay to keep its services up and running is through Ad revenue. FURTHER READING: Now, very powerful agencies like the FBI have methods to identify to a certain degree of certainty who you are and what you do online. This has to do more with psychology than hacking. Psychological patterns, ways of typing, etc can give them an idea of who is doing what but cannot definitively prove who a person is. It could only really be used to spy on someone and possibly lead to an interception of an illegal package for instance which will lead to an arrest. You can't really be anonymous if the FBI or some other major government agency is targeting you. But from hackers, corporations, etc you can to a good degree with a good VPN using a good VPN. If you're *REALLY* drop dead paranoid, use a VPN to connect to another VPN. Meaning the only thing your first VPN provider knows is that you requested to be connected to another VPN and the only thing your second VPN provider knows is that sites are being requested from your first VPN provider's server. I feel like I'm nurturing an unhealthy amount of paranoia in the minds of people who think they'll ever need to use this haha."
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62gjdz | when reading weather reports and it says 50% chance of rain, what does that actually mean and how is it calculated? | Repost | explainlikeimfive | {
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"It means that in all cases that look like what we see now, 50% of them will end up with rain, and the rest will end up without rain. It's based on two things: looking at past cases that resembled today's situation, and running a computer simulation that mathematically shows how weather works."
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62h08w | Can y'all simplify what's happening with/about/around Devin Nunes? | Repost | explainlikeimfive | {
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"He is Chairman of the House Intelligence Oversight Committee. In that position he would be resopnsible for looking into allegations of Russian interference with the 2016 election and any collusion in that interference by Americans, particularly Trump staff/surrogates. He as steadfastedly refused to look into this, and instead has tried to deflect attention away from it by claimin to have secret information supporting Trump's twitter allegation that \"Obama had Trump Tower wiretapped\" which, rather than share with the other members of h. s committee, he instead rushed to the white house to share with Trump staffers. And now it turns out that Trump staffers are the sources of that still unreleased and unshared information to begin with."
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62iewu | How was coding first invented without a coded thing to run what was being written? | Repost | explainlikeimfive | {
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"One of the early programming methods was punch cards. You would punch a hole in a card or a long sheet of paper. The holes in the cards would turn circuits on or off, which was used to send 1's and 0's to a computer."
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62ivnt | what is the difference between a president and a prime minister? | Repost | explainlikeimfive | {
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"Presidents are elected directly by the people in a vote. A prime minister is the head of the party with the most seats (or head of coalition of parties) in parliament. The PM is not directly voted for by the people, rather is selected by the party (but typically done in advance of elections so peeps obviously know who will be PM if any given party wins the most seats). Typical parliamentary system you just vote for your local MP (and local senate member if applicable). IMHO the most significant consequence of the difference is that with a prime minister you know the head of state likely has legislative power, bc his or her party is the largest. With a president it could be a lame duck in terms of being able to implement policy. Edit: and some places have both, with varying divisions of power."
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62k7bm | Why is, let's say 50 dollars written like $50 and not 50$? | Repost | explainlikeimfive | {
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"Back in the day, when books were kept physically in paper books you would write $1,000.00 in the ledger, because it makes it harder to modify the entry. If it was written as 1,000.00$ it would be easier to forge it to become, for example, 91,000.00$ by appending a single digit in front. It's the same for say, the thousand separator which separates groups of digits in three so that not only they're more easily readable, they make even changes from say, $1,252,001.- to $1,2152,001.- easily detectable. Source: I dunno, googled some and this here was an explanation that more or less sounded sound.",
"Different countries have different ways of writing their currency symbols. Some write it before the number, some after. Generally, people write it a certain way because that's how people before them wrote it. In the US we write the sign before the number because that's how the British wrote the pound sign before us. There are many benefits to writing the $ before the number. It makes it harder for forgers to modify numbers. You can't change $100 to $2100 by adding a number because there's a dollar sign in the way. Also it's easy to read the difference between dollars and cents on a sign, because the cent sign is written after the number. It's written like $3 and 50¢. Also if you wrote an amount as a decimal, 3.50$ the dollar sign is next to the cents values, and that could get confusing. But there is little to no evidence that any of these were the reason that way of writing currencies became standard. Language, symbols, and writing systems are constantly evolving, and their origins are too old to know with any certainty. People tend to keep doing what was done before unless there is a good reason to change. That's why we write the dollar sign before the number. Any more specific explanation is speculation at best.",
"The short answer is \"history\" and the slightly longer answer is \"nobody really knows.\" The US uses the English convention for writing currency symbols: the symbol of the primary currency unit goes before the number. So it's not just $50 but also £50, €50, ¥50 etc. Other languages do this differently, so saying that it's to reduce forgery seems like pure speculation: there is no good reason to suppose that only English-speaking businessmen saw a greater need to reduce forgery in this way.",
"Not an answer , but still relevant. In French, the dollar sign is always after the amount. In English $123.45 In French 123,45$ I have no idea why the English put the sign first. [ Edit : When I wrote 'French', I meant 'French Canadian' ]",
"I can't find anything concrete to confirm it, but I think it may be something that English borrowed from Latin and then stuck with. Certainly the symbols for pre-decimal British currency are derived from Roman currency. Some (most?) other languages put the currency symbol after the number.",
"Then the question becomes, why don't we say \"Dollars fifty\"?",
"Because the fact that the dollar sign ($) means end of line in a regular expression, hence one regular expression for matching 50 dollars would be [0-9]+\\\\$$ rather than \\\\$[0-9]+$ which is clearly and objectively more ugly.",
"I understood it to be written like that to provide a frame of reference for the number. I.e. $ 50 - so the currency is Dollar, and there are 50 of them. Otherwise, you are almost qualifying the number by its definition after the fact and I agree with the other comments, making it harder to add an extra number or two in front of the actual figure.",
"Fun Fact: The dollar sign originally came about by superimposing a \"U\" on an \"S\" (for US). People then got lazy and made it two vertical lines instead of a U, and got even lazier by putting only one vertical line. The more you know."
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62kfzu | If my ISP starts selling my browsing history, will everyone on our home wi-fi start getting porn click bait and cock ring advertisements? | Repost | explainlikeimfive | {
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"Not really. A lot of ad services specifically will not advertise \"adult content\". This is for a number of reasons, but one is that most sites don't want to be seen with that kind of advert. For the same reason, most advertisers will go to ad services that prohibit use on 'adult' websites. This is what really leads to the difference in ads on adult and non-adult sites. You won't likely see any ads for 'horny girls in your area' where you hadn't before, because they aren't really targeted at anyone.",
"Sorry if I'm a lot off-topic but how do VPN's factor into all of this? Are there ways for them to still track our history if we use them?",
"Want to know the fun part about this? This is repealing a bill that hadn't even been put into effect yet, your ISP has already been doing this for a long time.",
"If it's any consolation, if it does happen they don't have to know it was because you where on porn, plus, your dad watches porn so there's that",
"The way Internet Service Providers are gathering your internet history is by simply tracking what websites you request and what is delivered to your network. If you request to see URL_0 then the ISP will see your request and route the traffic accordingly. And now they log that you requested URL_0 and can legally sell that to anyone buying. If they can see which individual computer is the one requesting the website is another story. It depends on how far ISPs implement in order to gather your history. If they have router access, Which is likely, than they can see which specific computer requested to see those luscious videos. I believe this is a logical concern. But I do not think it will be a problem. As ISPs will likely have some sort of identifier (Say a local IP or MAC Address) for who wanted the traffic and target that person individually. It wouldn't make sense if sharon wanted shoes and they send bob some lovely coupons on his next pair of high heels. The targeted advertising wouldn't be effective then.",
"well first this is something that has been going on for a long time already and a they don't really need your history. A lot of ad services can track you by your ip address and serve up relevant ads to you across multiple sites and devices. That said though there are limit's like you shouldn't be seeing porn ads show up on walmart for example and most porn sites are basically on \"fringe\" ad networks because many reputable advertisement company's / brands don't want to be associated with those sites for the most part. Long story short is you really should only be getting porn ad's on porn sites or super shady sites.",
"Related question: Can my ISP sell my browsing history to my employer?",
"This is why i use tor for porn. Its slower and buffers more, but its less likley to leak my fetishes.",
"I have a question too. Is this similar to what Google already does to me? For instance, if I look up a tent on the internet I will receive adds for tents on the sidebar of websites for weeks. How is this ISP sale different?"
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62ln77 | How and why is HTTP not secure (vs HTTPS)? | Repost | explainlikeimfive | {
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"There are lots of ways. But anyone that owns any question you are communicating with or through, they can capture and copy and view anything that passes through their equipment. If you are communicating wirelessly, then that is even easier. Anyone on the same wireless network as you are can just listen to whatever it is your computer is transmitting.",
"If you send data over an unencrypted connection, anyone who inserts themselves into the network between you and the intended recipient can see what you're sending. For example, if your laptop is connected to a network that I control, and you go to an unencrypted web site and you log in on that web site, your laptop's browser basically says, in plaintext \"hi website, i am 16o1denRatio and i want to log in, and my password is \"greatpassword123\". If I have the right equipment connected to that network I control, I could read all this data as it passes through the network and leaves for the internet. I now know your password. If this is a wired network, it requires me to have access to the cables and network equipment if I want to do this, so it requires a bit of work. If this is a wireless, unsecured network, such as for example at starbucks, every laptop (or phone) can see what every other laptop is sending and receiving (because the radio waves from the wifi router are sent in every direction, not just in a straight line to a particular device). However, all these devices are normally set up to ignore all the information they see that isn't addressed to them, but there are ways to make your laptop stop ignoring data that's not meant for it, and then I would be able to read everything that every Starbucks user sends and receives, unless the websites and apps they use encrypt the data before sending it (and of course also only receive encrypted data). If a connection is encrypted, even if you have the ability to see the transmissions, the data in the transmission will just look like garbage (like when your laptop sent \"my password is greatpassword123\", to me it would just looks like \"jj5#¤%dsdjflsk%\"gg34\"), instead of actual usernames, passwords, or any other readable data."
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62mdxn | Why do public toilet seats always seem to be horseshoe shaped but home toilet seats are complete circles? | Repost | explainlikeimfive | {
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"Also, if you realize you did not lift the toilet seat whilst peeing, the gap will act as a passage for your pee so you can still lift the toilet seat up without having to hold your pee in.",
"Right from the Toilet page on wikipedia, apparently it's so folks can wipe from the front without having their genitals touch the toilet. > The purpose for this seat design is to allow women to wipe the perineal area after using the toilet without contacting the seat. It also omits an area of the seat that could be contaminated with urine, and avoids contact between the seat and the user's genitals. I suppose because public toilets are bound to be dirtier than your own - plus you have a much better idea of the last time your own toilet was cleaned. I've seen plenty of home toilets with the split fronts as well though."
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62mymp | can someone explain how I'm "wasting water" when I'm turning my faucets on? | Repost | explainlikeimfive | {
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"All of that process uses energy and resources. Your individual excess water usage might not really matter but if millions of people are doing that, that's heaps of resources devoted to making some noise while you brush your teeth. Also depending on where you live fresh water might be scarce and letting it run for nothing (again multiplied by everyone in your city) is a huge volume of water used for nothing.",
"Water isn't generally recycled, it gets cleaned up a bit and is then dumped in the ocean or a river which ultimately carries it to the ocean. It may be used for purposes such as cooling power plants, in order to conserve fresh clean water, but it's not going to come back out of your tap anytime in the near future, not till it's ultimately run off to the ocean and evaporated to fall on the land as rain again. URL_0"
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62o0um | How did language begin, and how did we assign words to stuff? | Back when using words to communicate was a new thing, how did those people first assign words to stuff and let others know that a certain word meant a specific thing? For example how did the very first humans to use the word "love" communicate to the other person what they meant by that word? | Repost | explainlikeimfive | {
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"Oh, if only anthropologists and linguists could go back to that moment and see how it happened! But they can't, so we have to speculate based on incidents we have been able to observe. One of my favorite stories to talk about for this example is the birth of Nicaraguan sign language. Back in the 70s, deaf people had no centralized education. They were isolated from each other and had no means of communication. In the late 70s and early 80s they started putting deaf children into a special school and trying to teach them spanish and lip reading. It didn't go very well. But something remarkable happened. The kids basically invented their own sign language to start communicating with each other. The adults had no idea what they were saying so they brought in some linguistic experts to figure it out. It started as a simple pidgin, but over a few years, the students evolved it to a full language with verbs and verb tenses and other complex patterns of speech. This example is often used as evidence that language is something that's just hardwired inside of the human brain. That our brains just work that way. So if the human brain just works that way, then you have to go back to speculate about how earlier humanoid species might have started using language to get to your answer."
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62oqqp | Please explain Unitarianism in the simplest way possible. | Repost | explainlikeimfive | {
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"There are two fairly distinct movements that call themselves \"Unitarian\". The first refers simply to any Christian movement that rejects Trinitarianism (the belief of one God in three Persons), Binitarianism (one God in two Persons), or any of the other Christologies that view God as anything other than an absolutely single entity. The more common meaning today refers to the Unitarian Universalist Association, its members, churches, and philosophy. They are a movement that was originally Unitarian in the Christian sense above (and also Universalist, meaning they believed everyone went to Heaven), but now rejects any one religious doctrine in favor of a philosophy of \"recognizing the inherent worth of every human\" and \"supporting everyone's search for meaning\".",
"Simplest? I'll do my best: There is one God. Jesus was a good human dude. Not god People are basically good, and they can choose their destiny, but can and do often choose evil, which is a real thing. The Bible is cool, but not perfect. No one religion is all- right. No one creed is perfect. Hell? Meh..... Be kind.",
"The way I always heard it when I went to a Unitarian church is \"God is one and not a trinity; Jesus was man and not divinity.\""
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62r3o0 | What is the point of a conductor in an orchestra when everyone knows what they are playing? | Repost | explainlikeimfive | {
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"Everyone knows their parts and can play it nice on their own but once you have to coordinate a complex piece of music with lots of other musicians it can be very hard. First of all sound takes some time to travel from one side of the stage to the other. So if you were to base your tempo on someone across the room you will be off and it will sound horrible. So you need to use visuals to find the tempo as light travels much faster. This is why the conductor swings his arms in beat with the music. But there is also a lot of other things that is different each time you play a piece. The performers are in different states of mind, the instruments might be affected by temperature and humidity, the sound changes depending on the room, the audience act differently, etc. So the conductor is \"playing\" on the performers as if they were a big instrument. If one section of the band is too loud he can tell them to bring it down, if someone gets out of beat he can tell them to they are ahead or behind, some pieces have sections that is deliberately changing beat or does not have a beat and it is up to the conductor to find the right timing, etc. Basically if you have a large group of musicians you need someone to coordinate them to make great music.",
"In addition to keeping it all together during a performance, most of the hard work a conductor does is during the preperation that leads up to the performance. It is the conductor that usually decides and applies what the musical details are.",
"Explainations here are very good, and I would like to add that the conductor may look useless during the representation, but s.he's responsible from how the final piece will sound like. An example of the choices made by the conductor to change the sound of a piece can be heard in the difference between the interpretations of the same Mozart's Requiem Lacrimosa, [one from Celibidache]( URL_3 ) and [one from Bernstein]( URL_0 ). Apart from the speed, you can notice that the violin \"response\" melody at the beginning of the movment is much louder in Berstein's, and that it has a lot of room to 'express' : you hear it a lot more than in Celibidache's. The *qua resurget* from Berstein sounds way more split, probably because of the slower pace, but in the the following *lacrimosa dies illa*, you can hear the alti louder in Bernstein's (this is a faint difference, but still). Another example is the baryton's entry at 34:48 on Celibidache's version (36:31 for Bernstein) : they acentuate the first note, then the next one is lower. This creates more movment than in Bernstein's, where the two note are sung with the same power, adding to the 'rigorous' moment. At the opposite side of the spectrum, the same moment in [collin davis's version]( URL_2 ), the men sing at the same level all the time and the other voices are forced to sing louder to be heard (notice that in Celibidache's, the men go lower so we hear the alti and tenors). That's one of the many examples you can give (and they're just in 2 minutes extracts !). Try to listen to two different versions of the same piece (why not Beethoven ? [one]( URL_1 ) and [two]( URL_4 ) ). Listen to the different paces, and the crescendi at around 10sec into the 5th symphony. (btw Duhamel conducted tthis year's New Year concert in Vienna, and it may be cool to compare the Radetzky's march versions over the time). You could try the same with different versions of the Star Wars theme, too, comparing professional orchestras to local schools playing it and try to notice the differences)",
"Helps keep everyone on beat, cues different groups in (if you have to count like 80 beats of rest and miscount) I think most important is the conductor directs the expression, phrasing, etc of the music. How loud to get, how quickly you want to get loud. What melodies should be heard more and which ones softer. Oh yea, and when to stop playing!"
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62unxb | What happens if you turn on a lamp in a vantablack room? | Repost | explainlikeimfive | {
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"It would look like a flat black background with a lamp in front of it. Sort of like [this]( URL_0 ) only without the dangling lamp parts being visible if they were painted Vantablack."
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62vt39 | Why do you get something like a bright vision when you rub your closed eyes? | Repost | explainlikeimfive | {
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"Nerves can be stimulated by many things. Some are built to trigger when they get hot, or hit by light, or touch a certain molecule. No matter what it is, the nerve will send the same signal to the brain. The brain interprets the signal based on which nerve brought it. Imagine two babies, one in a red hat and one in a blue hat. The red one cries when it's hot and the blue one cries when it's cold, and the cries sound the same. However, you can determine the temperature of the room based on which baby is crying. The nerves in your eyes that are activated by light can also be activated by mechanical force, ie, rubbing. Imagine if the red hat baby also cries if it was being spanked. If someone spanked the baby and you saw it crying, you'd think the room is hot, even if it isn't. This is what is happening with the brain. It detects signals from the light receptor nerves and interprets them as incoming light. You'd get the same effect if you rubbed your open eyes, but there would be obstacles. First, lots of real light is coming in, which would overshadow the false lights. Like a speaker blasting heavy metal in the baby room. If you were in total darkness, it would also hurt and you'd be too preoccupied to notice the false lights. Like if the microwave went off, signalling the completion of your hot pockets. Would you go an tend to the babies when there are hot pockets waiting to be eaten? I didn't think so."
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62whn8 | How is the calorie content in food and drinks determined? | Repost | explainlikeimfive | {
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"I've heard of three methods. The first is to burn it and see how much heat it produces. This is basically what the body does except that we use enzymes to control the burn rate. In labs they burn it in an oxygen rich environment in a sealed insulated container. This will give you a good measure of the total calories in food. The second is to feed a lab subject carefully measured quantities of food and to regularly weigh the subject and their feces while monitoring their physical exertion. Then we can back calculate the calories from the relationship between these measures. This gives you a good measure of how many calories humans absorbed from food. Finally for some foods we just add up the calories in the ingredients. This has the advantage of being significantly easier than the other two."
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62xxyu | What stocks are | Repost | explainlikeimfive | {
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"A share is a piece of a company that you can buy. Stocks are just all the shares without regard for which company they belong to. You can buy a share of a company and sell it later. That's the primary thing most people think about when they're playing the stock market. If that share's value goes up, you can turn a profit by buying it when it's cheap and selling it when it's expensive (\"buy low, sell high\"). Unfortunately, you don't know if a stock will go up or down, so you're playing a bit of a guessing game. Shares rise in value if the company either did well in the last fiscal quarter (in the last few months) or is predicted to do well in the next fiscal quarter (in the next few months). There are tons of other things you can buy and sell that aren't stocks on the stock market, and different ways of buying and selling everything, but I'm just giving the very basics here. If you want to know how to get started, you should look it up in /r/personalfinance or similar. Someone has probably already asked how to get started, so you can just look for that thread."
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63071u | If you were in space without a suit - what would kill you first - the pressure difference, temperature, lack of oxygen, radiation or something else? | Repost | explainlikeimfive | {
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"Lack of oxygen to the brain would kill you first. How you get there is a bit complicated. You can make your last few moments a lot more painful by trying to hold your breath, as your lungs and your body can't handle the pressure of gases inside your lungs trying to escape into the vacuum outside, causing very violent damage to lungs and surroundings. Because the estimated time you have to live in space without a suit is measured in seconds or minutes, I'm not exactly sure if it would dramatically shorten your lifespan, but it would make rescue almost impossible, and it would most certainly be really painful. So assuming you're not holding your breath, you would have maybe 10s before you lose consciousness. After this, lack of oxygen and various problems related to pressure or lack thereof would kill you over the course of maybe 2 minutes. My sources estimate that if you're rescued up until 90s after entering vacuum, you have fairly good chance of walking it off, but any longer than that and your odds of survival are dropping fast. So maybe 2min before lack of oxygen kills you. If you were not under direct sunlight(finding a shade in space may be difficult, but lets say you managed to find one, otherwise your might never freeze), you would die of hypothermia within a couple of hours. Because lack of oxygen kills you in less than 2 minutes, this isn't really relevant. If you were under direct sunlight, you would not necessarily freeze at all, and instead you'd have to worry about really severe sunburns. Radiation would not kill you, probably. Your risk of getting cancer would increase slightly, but onset period of cancer would probably be measured in decades. Even if you got terribly unlucky, it's hard to see how you could die of radiation in less than a year of space exposure. Sources: URL_1 URL_0",
"If you tried to hold your breath your lungs would likely rupture, killing you in a few seconds. If you exhale before leaving the ship, you've got about 15 seconds before you pass out, and then a couple minutes before you die from lack of oxygen. Everything else would take longer to kill you.",
"Some of this happened to a NASA volunteer subject in 1966 when he was accidentally depressurized in a test chamber. In a zero-pressure environment, gases come out of solution and water evaporates. He lost consciousness in about 15 seconds because his blood was rapidly de-oxygenated. In air you can last 2-3 minutes without breathing because it takes that time use up the oxygen that your blood is carrying. You'd get some ice in your airway from evaporative cooling. When a liquid evaporates it takes some heat with it. You can demonstrate this for yourself if you get a can of compressed air, turn it upside-down, and spray it on something. The liquid inside (which isn't air at all but that's for another day) sprays out and immediately evaporates, leaving a little bit of ice wherever it landed. Apart from your mouth, nose and throat, the rest of your body would take some time to get cold because a vacuum doesn't conduct heat very well. Water in your soft tissues would start to evaporate and you'd swell up like the Michelin Man. From animal studies, it appears you can survive if you're put back in a pressurized environment within a minute and a half, before your heart muscle is seriously damaged. The point about lungs rupturing would be an interesting experiment if you could do it without dying. It is true you can do that to your lungs coming up from a deep SCUBA dive but that involves pressure differences of a few atmospheres rather than the one-atmosphere difference between space and your space ship. It might depend on what you were doing with your chest wall and diaphragm. Your chest withstands substantial pressure differences between inside and outside every time you blow up a balloon and there are people who can blow up a hot water bottle to the point where it bursts. As for radiation, if you were on your way to the Moon or Mars you wouldn't be protected by Earth's magnetic field and if you were REALLY unlucky you could get caught in a storm of charged protons that could cause radiation sickness, but of course you'd be dead from hypoxia before that. According to [this NASA page]( URL_0 ) \"Between the Apollo 16 and 17 missions, one of the largest solar proton events ever recorded occurred, and it produced radiation levels of sufficient energy for the astronauts outside of the Earth's magnetosphere to absorb lethal doses within 10 hours after the start of the event. It is indeed fortunate that the timing of this event did not coincide with one of the Apollo missions.\""
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|
631lnw | Why does inbreeding only cause disadvantageous mutation? | Repost | explainlikeimfive | {
"a_id": [
"dfqldat"
],
"text": [
"It doesn't cause them. It exposes them. We all have mutations, but we also have two copies of each gene. They are called alleles. If your parents are not related, it's unlikely they will have the same bad copy. If they are related, they could have both inherited the same bad allele from their shared ancestor. Mutations usually result in losing that gene's normal function. As long as you have one good copy, you do fine. If you have both bad copies (the same mutated version) you're SOL."
],
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|
632rj8 | how do cell phones make calls when they don't have a sim card or any carrier attached to them? | Repost | explainlikeimfive | {
"a_id": [
"dfqv33e"
],
"text": [
"When you have no sim card inserted, the phone can still connect to nearby cell towers however you'll get a no service notification because whichever network the cell tower belongs to is refusing connection since it can't tell what network the phone is linked to. In the United States all carriers are required to connect any 911 calls regardless if the call is coming from a phone in the carrier network or not. Even if there's no service or you don't have a sim card your phone can still call 911 unless you're in the middle of nowhere."
],
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|
63611g | How did the earliest humans know how to reproduce? | Repost | explainlikeimfive | {
"a_id": [
"dfrkuey"
],
"text": [
"Yeh it was instinct, in the same way sexual animals know how to reproduce. They saw a pretty stone girl and wanted to put their penis in them, and hey presto!"
],
"score": [
7
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63a7a2 | Is some sort of time travel possible if humans are able to move almost as fast as the speed of light? | Repost | explainlikeimfive | {
"a_id": [
"dfshhoo",
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"text": [
"Theoretically, yes. A human could effectively \"move into the future\" relative to other humans. Time is experienced more slowly at higher speeds (\"time dilation.\") The effect ramps up sharply as one approaches the speed of light. At 2/3 the speed of light it's only about 34% slower, but at 99% of light speed it's over seven times slower, at 99.9% almost 23 times slower. So, let's say we find a brave ~~astronaut~~ chrononaut who gets on a spaceship, flies away for six months at 299,500 km/s (99.9% light speed) then six months back at the same speed. He would find that almost twenty-three years had passed on Earth, with his friends and family considerably older, yet he would only have aged a year. For my money, that's time travel. Practically speaking, mass also increases sharply as one approaches light speed, so getting up to relativistic speeds isn't easy. Relativity corrections do have to be made to GPS satellites, which go fast enough to experience time just a little slower relative to us.",
"Sure, forward in time. But we sort of already have that kind of time travel - we travel forward at the rate of one second per second. But yes, if you somehow were to accelerate up to near the speed of light, and then slow back down again after, you'll have aged less than the people who did not accelerate up and down again. This is called the *twin paradox*. URL_1 URL_0"
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"https://www.youtube.com/watch?v=0iJZ_QGMLD0",
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|
63b8nn | How do we determine how many calories are in a food? | Repost | explainlikeimfive | {
"a_id": [
"dfsqq7a"
],
"text": [
"One method is called a bomb calorimeter. It's a special device that burns food and measures how much heat the resulting fire generates. It's carefully designed to detect the energy output of just the food and not the ignition source (thing that sets the food on fire)."
],
"score": [
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63bnj1 | How do websites detect that you're using an Ad-blocker? | Repost | explainlikeimfive | {
"a_id": [
"dfsvwij"
],
"text": [
"When you use an ad blocker, it removes the HTML element for the ad from the page or modifies it to be hidden. The site will have some JavaScript running to check for modifications like that, and if they occur then the site knows you're blocking the ads. There are some other methods like /u/hashtag_lives_matter mentioned, but this is the most common and simplest to implement."
],
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|
63g7qh | If all our cells get replaced every 7 years, what is keeping tattoo's so permanent? | Repost | explainlikeimfive | {
"a_id": [
"dftttbz",
"dftty93"
],
"text": [
"The tattoo ink isn't part of your skin cells, it's literally just sitting in between cells of your lower skin layers, like [in this picture]( URL_0 ). It's like a little bubble of ink floating in a sea of skin cells. So the cells around it are constantly being replaced, but the ink is designed to be very stable and stick around, suspended in your body, for a very long time. Your body does slowly break it down, so tattoos do fade with age, but only over a long period of time.",
"All your cells do not get replaced every 7 years. Neural tissues are not replaced. Bones take 10 years. But tattoo ink is placed below the skin, but above the deeper tissues."
],
"score": [
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|
63gjlk | If Every Other Major Object in Our Solar System Has a Name, Why is The Moon, just 'Moon', and The Sun, simply 'Sun'? | Repost | explainlikeimfive | {
"a_id": [
"dftx3jo",
"dftwdmi",
"dftwtrz",
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"text": [
"Moon and Sun got their names long before we knew that other moons and suns existed. The Moon was just Moon - it was a proper name, the same as Mars or Venus or Jupiter. When we found out that other planets had things orbiting them, we called them \"moons\" because they reminded us of Moon. But the proper term is \"natural satellite\". Little-m \"moon\" is just an informal term based on their similarity to big-M Moon. The same reasoning applies to other stars; you can call them little-s \"suns\" based on their resemblance to the Sun, but the proper term is \"stars\".",
"The moon has a name. It is called Luna. The Sun has a name. It is called Sol. This is why we have a solar system. That we don't use the names doesn't change that.",
"According to the International Astronomical Union (IAU), the official name-givers on this planet, the name of our star is Sun and the name of Earth's moon is Moon. I guess using Sun rather than The Star is a genuine name, but for The Moon, you're right. A bigger problem is that most grammar guides don't capitalize Sun and Moon, as though they don't accept the IAU's notion that we only have one of each. This seems like a grammar question, not a physics one.",
"Lets go back 3000 years. Ancient people looked up at the sky and saw three kinds of things: they saw a big yellow ball, a big white ball, and lots of tiny dots. They called the yellow ball \"Sun\", the white ball \"Moon\" and the tiny dots \"stars\" (or whatever word they had for them in their languages). They also realized that a few of these \"stars\" are actually moving, so they called them \"planets\" (meaning \"wanderer\" in Greek). These names carried on over time and between languages. Fast forward to a couple hundred years ago. Astronomers realized that the planets as well as Earth are all orbiting around the Sun, and that the Moon is orbiting Earth. They also found out that the planets also have things orbiting around them - so they called these things \"moons\" as well. All these moons were given proper names, but our own moon just kept its name - *The* Moon. The same thing happened with the Sun - we realized that the Sun is a star just like all the rest we see in the night sky, so suddenly the terms \"star\" and \"sun\" became interchangeable. However like the Moon, our Sun kept its original name - *The* Sun.",
"The Moon and the Sun were all named (not those particular names) before we knew of other Moons and Suns in large mass. And Earth was named when we thought the Earth was special in some way.",
"Jupiter's name is Jupiter as much as the Moon's name is The Moon. Not everyone calls it Jupiter, and not everyone calls the Moon the Moon. The reason why the Moon doesn't appear to have an \"individual name\" but share its (frequently used) name with a classification of objects (moons) is because we named that class of objects for the Moon, our first representative of it. So it's not that the Moon just got an catagory name like naming a car \"car\" but the otherway round."
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63gp3i | Why are there unnecessary and poisonous chemicals like tar in cigarettes? | Repost | explainlikeimfive | {
"a_id": [
"dfu07jf",
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"text": [
"They don't add tar to cigarettes. Tar is, *by definition*, the byproduct of combustion. So you get tar *because* you burned the cigarette. There is quite the laundry list of chemicals that *can be* added to a cigarette, though that doesn't necessarily mean it is. These fall into a number of categories: * Chemicals to increase nicotine absorption into the body. * Chemicals to increase nicotine vaporization in the cigarette. * Flavor compounds. * Fire retardants for safety. * Preservatives to increase freshness, stability, and shelf-life. * Chemicals to prevent you from getting sick from other chemicals. There's no knowing what exactly is in your cigarette as the tobacco companies aren't required to disclose their blends on their packaging, they're only required to use the approved chemicals up to their maximum safe dosages. The nicotine absorption and vaporization chemicals aren't part of some conspiracy to get kids hooked, nicotine is the active ingredient people want - the reason why they smoke - the chemical that *gets them high*. Can you believe it? People smoke cigarettes all the time, getting intoxicated by a drug, and yet they're allowed to smoke these things just about anywhere, or while operating heavy machinery. I'm not a habitual smoker, but when I do it *fucks me up*, depending on how much anywhere from a few minutes to a couple hours. So that's why they add poisonous chemicals - people want more nicotine, tobacco is going to deliver more nicotine. They don't just add it, they can't just add it, and even if they did, they need to increase the amount you can and will absorb, which, there's more nicotine in tobacco than you're going to absorb anyway, so they have plenty to work with. But here's a fun little gem: tobacco is Chernobyl nuclear-style radioactive, because all commercial tobacco in the US is fertilized with apatite, a naturally occurring mineral that is typically radioactive and used as a fertilizer. It's illegal to use it on food, but tobacco has no such restriction, and this shit is *cheap*. It makes the ground radioactive and when they switch the fields back over to food, the food becomes radioactive. How radioactive is tobacco from this stuff? Well this much I can say from experience: cigarettes are a shipping HAZMAT material *only* because of the amount of radiation they throw off. Cigarette trucks set off radiation alarms at shipping checkpoints, and release more radiation to the environment in a day than a nuclear power plant. A pack-a-day smoker receives the equivalent of 2,000 chest X-Rays a year. The recommended safe maximum exposure in a one year window for a civilian is 4. **BUT WAIT, THERE'S MORE!** If you are *utterly terrified* of radiation and cancer, you god damn should be. But if that weren't enough, let's talk briefly about \"carcinogens\". Yes, carcinogens, that lovely word we hear so often we don't hear it anymore. If you live in California especially, EVERYTHING give you cancer, according to them and their testing, right? Well here's the thing. Burning tobacco produces more than just tar, the chemical cocktails created in the tar are carcinogens. These are non-radioactive chemical compounds that absorb into your cells, come in contact with your DNA, and *rips it to shreds*. Your DNA tries to heal itself, and the errors are what we call \"cancer\". If radiation is a cute cancer puppy that just wants to love you, then chemical carcinogens are a swarm of near-immortal cancer locusts ravaging your countryside and blotting out the sun. These chemicals are *extremely* aggressive and long lived, and far more active than the radiation. If you are terrified of the radiation, then you should be shitting your pants right about now. And the dangers of radiation and carcinogens is cumulative. The longer you live, the more you're exposed to, the more likely it's going to kill you. This is why smoking around children should be a punishable crime. A couple more things: death from smoking related cancer is higher than it has ever been, even for non-smokers, even though smoking is at an all time low. See above about the children. And almost no tobacco is imported into the US, especially not for cigarettes, because if you think we put weird shit in our cigarettes, the original Indonesian Kretek can contain up to 25 mg of *rubber glue*, among other things.",
"The whole \"unnecessary and poisonous chemicals\" in cigarettes is a big distortion. Any time you burn plant matter, you are going to release a bunch of toxic chemicals in small amounts, whether it is tobacco or a camp fire. That is an unavoidable part of smoking.",
"Tar is a byproduct of burning plants. The same is true of carbon monoxide and many of the other chemicals.",
"The tar isn't in the cigarettes when you buy it. It is created by the process of burning the cigarettes. Consuming tobacco by other means may reduce the amount of tar that would be created, or eliminate it completely.",
"'Tar' as it refers to cigarettes isn't exactly what you think. It's not tar that you would use to patch a driveway, and it isn't added in. 'Tar' just refers to the resin-y (resinous?) Mess that forms from smoking product. Think the dirty black slime at the end of a joint, both are 'tar' in this sense. Wiki-Source: Tar, Tobacco Residue URL_1 Which isn't to say there aren't a shit ton (technical measurement) of additives in commercial tobacco. They are sort of necessary. Some are natural-ish (plant extracts) and some are more man made. They serve as flavor enhancers, preservatives, products to maintain moisture content, products to keep the tobacco 'clumped' properly so it doesn't reduce to powder. [Here's a list]( URL_0 ) (Wikipedia again) although it's a little light in detail of what each product is for.",
"Tar comes from the burning plant matter, the other chemicals do things like make the cigarette stay burning, make it burn more evenly, or slower..."
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|
63gz83 | Why is it illegal to use chemical weapons during war but it's perfectly okay to bomb, shoot, stab, drone strike and beat someone to death in the same context? | Repost | explainlikeimfive | {
"a_id": [
"dfu0kn5",
"dfu3apu",
"dfu4gdd"
],
"text": [
"Chemical weapons have other issues associated with them (such as use against civilians), and beating someone to death slowly would be considered cruel and isn't typically allowed unless there was no other reasonable way to deal with the situation. Bombings might sound bad, but many people hit by bombings are killed pretty quickly. Chemical weapons often kill slowly and in am agonizing way.",
"Chemical weapons often result in horrifying effects on a large scale and the user has little control of who is effected. And civilians are the most vulnerable to them. Bombs, missiles, and bullets are typically used on specific targets for a military gains. Also, people are OK with killing cars with missiles because we see it all the time. Its normal. That said, when push comes to shove, and you are about to lose an actual war, you use all the weapons you have. The world tried to ban them because you can't use what you don't have.",
"Blame WW1 when chemical weapons were just getting started. The generals were well used to conventional weapons like bullets and bayonets. But chemical weapons were a new thing, horrifying, and it showed them just how terrible war is. Next, chemicals poison the land and lie in wait for the weather conditions to change. A shift in wind or sudden rainfall could start killing their own men. Even days later. They cannot be controlled. Next, a well prepared army had little to fear in chemical warfare, civilians did not have those preparations. The generals wanted to feel honorable, and while it's honorable to kill 10000 soldiers in war, it's not honorable to kill 10000 civilians. By the same token, there are bans against cluster munitions and minefields, bans that came about from the precedence of banning chemical weapons."
],
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|
63h02n | Why would you choose a trebuchet over a catapult? | Repost | explainlikeimfive | {
"a_id": [
"dfu1pky",
"dfu0sht",
"dfu0qcv",
"dfu96ps"
],
"text": [
"By \"catapult\", I assume you mean a device where a wooden length is bent back to gather force to hurl a stone. The upper limit of the force you can gather for this device (which thus sets your upper bounds for range and weight of projectile) is a function of the tensile strength of your \"bending arm\". With a fixed maximum force, that means you have a set maximum range. You're also stressing your \"bending arm\" in the ordinary process of use, which means each use carries the risk of partial to catastrophic failure with the arm breaking at some point. The trebuchet gathers force through gravity and a lever-arm. The weigh-bearing basket is the limiting factor on how much gravitational energy can be stored, with the lever-arm determining the final energy released. Thus, it's possible to generate a **lot** more energy, for greater range, heavier projectiles, or both. The trebuchet has its own risk of failure, but it's most likely to fail after the shot is released. It also has a longer \"reload\" time, as it's necessary to unload the basket, reset the arm, and then reload the basket.",
"Speaking from personal experience, back when I was in high school, we had to design and build a catapult for physics class. My classmate and I built a trebuchet(which is still technically a catapult). We went for the trebuchet mostly because it was easy to build(just a pole on a pivot with a weight on the end) vs a catapult(which would have required finding a material that would be strong enough and finding a way to mount it). So yeah, I chose a trebuchet because it was easier to build than a catapult.",
"A trebuchet is capable of hurling heavier weights a longer distance as it doesn't rely upon the elasticity of materials but rather weight and gravity. However they are often considered to be larger and to be harder to move and quickly reload.",
"ELI5: why do people care so much about this question?"
],
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13,
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|
63hio2 | What Determines the Value of Art? | How can someone paint something like [this]( URL_0 ) and have it sold for millions of dollars when anyone in the world could paint the same thing? | Repost | explainlikeimfive | {
"a_id": [
"dfu4w53"
],
"text": [
"Art is subjective therefor it's worth what someone is willing to pay for it. It has no *real value* other than the value someone would place on it. Paintings can go on sale for millions but if it doesn't sell its worth fuck all. If it sells for 30k it's worth that to some people, it may re sell for more or less depending on the artists popularity and rarity etc."
],
"score": [
6
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63hmf4 | Why are electric vehicles more carbon efficient? The electricity comes from power plants, right? | Repost | explainlikeimfive | {
"a_id": [
"dfu5w5w"
],
"text": [
"A car engine turns about 30% of the energy from gas into motion. The other 70% is lost as heat. Power plants that use fossil fuels use the heat from burning fuel to heat water that turn a generator. This is a more efficient conversion of the energy. Add to that, that not all of the electricity is generated by fossil fuel. Some planets are hydroelectric, wind, or solar. So an electric car is also running of some carbon-zero energy sources as well."
],
"score": [
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} | [
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|
63kqbi | Why is a human's dead weight heavier than if they were even slightly conscious? | Repost | explainlikeimfive | {
"a_id": [
"dfuwfpx",
"dfuuuug"
],
"text": [
"A conscious person will shift the centre of their weight closer to the person carrying them, thereby making them easier to lift. An unconscious persons limbs and head will dangle off to the side increasing the effort required to lift. It's like the difference between carrying a bar bell (simple enough) versus a sofa (too unwieldy). They're not heavier. It's just their centre of mass is uneven forcing you to put more effort to maintaining balance.",
"The body will naturally try and move in the easiest way possible, so it will shift its weight and help as much as possible while concious"
],
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