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pprid | This may sound daft but, when Comets go though space they appear to have a tail, but space is a vacuum so what would be causing the tail is there is no resistance? | askscience | http://www.reddit.com/r/askscience/comments/pprid/this_may_sound_daft_but_when_comets_go_though/ | {
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"The sun. The tail of a comet doesn't indicate where it is going but rather where it is relative to the sun\n\nEdit: _URL_0_",
"Indeed, for part of a comet's orbit (when it's moving away from the sun), its tail is actually ahead of it."
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6soq46 | [Mores, Customs & Folkways] Do historians use literature to study areas that are well documented or is literature only used if there are no other sources? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/6soq46/mores_customs_folkways_do_historians_use/ | {
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"Hi, history is more interdisciplinary than the question seems to imply - but it's also a big question. \n\nCultural history may involve study of fictional literature; for example, a student could examine how Shakespeare's portrayal of the Plantagenets in his history plays related to propaganda reinforcing Tudor / Elizabethan legitimacy. There, literature is a central part of historical study. \n\nIn other instances, it may be a way of locating supplementary details not recorded or with minor coverage elsewhere, particularly in the area of social history, customs and everyday life. It is certainly more useful for older history, particularly medieval and early modern, where there is not such a glut of evidence as there is in, for example, the second half of the twentieth century, but in most cases it isn't a binary either/or. And it must always be borne in mind that literature is fictional or mythical, and that there may not be ways to check whether a social habit, for example, was widespread, or fictional. A historian might cite an example from a well-known novel to liven up a book, if it is a good and relevant example. \n\nBut it would not be good practice at all to cite, say, a historical novel about the Second World War when writing a factually-based assessment of military planning: there are countless better secondary sources, never mind primary ones, and there may be artistic licence used. "
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2kdebe | if bathroom hygiene is so important why don't we get sick after performing oral sex? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2kdebe/eli5_if_bathroom_hygiene_is_so_important_why_dont/ | {
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"It's more a matter of frequency. If you consider all the times in a day you touch a person (shake hands, etc.) or touch something they touch (doorknobs, etc.), it ads up to a lot of exposure. \n\nIf you sucked that many dicks, every day, from that many random people, you would probably get sick a lot.",
"I don't know about you, but me and my ex made a habit of you know.. refreshing our selves before we did anything. Not because we were gross individuals but because it just made sense to us.",
"I've never died in a plane crash. That doesn't mean planes don't crash or that people don't die as a result of plane crashes. STD's can and are sometimes transmitted via oral sex. For some types of STD's, the likelihood is somewhat diminished in proportion to becoming infected by way of vaginal and/or anal sex but the possibility does exist and people do \"get sick\" because of unprotected oral sex.",
"What do you mean by \"get sick\"?...a cold? Flu? If that's what you mean then the answer is: because you catch a cold or flu virus from hand contact or from someone coughing/sneezing on you. Now, if you're the one giving oral and the receiver has a cold, they could cough on you or cough in their hand then touch your face and you'd get sick. But you won't catch the cold from their genitals. (Sorry for my tame choice of words. I'm a nurse...trying to keep it professional;)\n",
"I don't think it's the weiners that are the major culprits... it's the hundreds/thousands of instances of hand-to-object-to-hand contact in a place like a bathroom that are.\n\nJust wash your hands often. And shower once a day. You'll be fine.",
"Hygiene is a habit. Oral sex only happens 3 times a day.",
"I know plenty of men that wash their hands before heading to the urinals with the mentality of \"my penis is the cleanest part of me (not in contact with the outside world after showers etc.) but my hands are disgusting because they've been everywhere.\" So it's really a hygiene factor if we're talking about basic viral/bacterial infections. \n\nNot a medical professional. "
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8t6r2y | how did people get enough heat to smelt metals before the industrial age? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8t6r2y/eli5_how_did_people_get_enough_heat_to_smelt/ | {
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"Coal fire forges are able to reach temperatures of about 1900 degrees C which is more than enough to melt most ‘primitive’ metals such as iron, bronze, copper and steel. ",
"They melt at much lower temperatures than you might think.\n\nYou can take raw iron ore and pack it into a \"bloomery\" which is basically a mud-and-brick covered pile of ore and coal/charcoal. Light it on fire and the outer materials insulate the inner layers, and the heat eventually gets to the point where the iron melts out of the ore and pools in the bottom.\n\n[Blast furnaces](_URL_0_) have also existed for about 2000 years."
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6ees71 | How did scientists measure the radius of atoms and other stuffs? | They can seem to measure very accurate things at 10 decimal places. How do they do it? | askscience | https://www.reddit.com/r/askscience/comments/6ees71/how_did_scientists_measure_the_radius_of_atoms/ | {
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"The most accurate measurements are spectroscopic measurements, in which the energy between states of e.g. atoms is measured. These measurement happen typically with lasers, the frequencies of which can be very well controlled. This is the domain of atomic physics, which is mainly quantum mechanics dealing with discrete energy levels and interaction of matter with photons.\n\nFirst, remember that the energy states of electrons orbiting a nucleus are quantised.\n\nIn a spectroscopic measurement, the frequency of a laser is scanned along a certain range while it passes through a sample, e.g. a gas of atoms. Most of the time, the light will not interact with the sample. Only when the frequency (and thus the energy of the photons that make up the light) is equal to the energy difference of two internal states of the atoms, some of the light can be scattered. In this way, the energy levels of atoms are measured very precisely.\n\nFinally, one can calculate from theory what the electron orbits and the corresponding energies should be. These calculations depend however on some constants, such as the Bohr radius, which describes the distance between the nucleus and the electron in a hydrogen atom. By comparing these calculations to the results of the measurements, these constants are retrieved. (The Bohr radius is now known with a relative uncertainty of 0.2 parts per billion.) These constants can then be used in the theory to calculate the sizes of different atoms.\n\nTL;DR: Experiments measure the spacing between energy levels, theory relate these energy differences to (among other things) the sizes of electron orbits. Both lasers and quantum mechanics are very accurate.",
"A method called diffraction can be used to measure small gaps. Pretty much waves do a certain pattern when you get the wave length to be the same length as the gap between things with this by controlling wavelength and knowing what to expect you can measure gap between things. As particles have waves you can use neutrons with their very short waves to measure small gaps between things but em waves can also be used for larger gaps. However I don't think this can get down to the level you are referring too."
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1f4e1v | How is the infrastructure of the internet built? | I understand some basic concepts, such that there are servers that users request information from, or upload information to, but how is it all physically organized? Are there central hubs that everything goes through? How is a connection established between one computer another for that information to be exchanged? How are efficient routes maintained? It seems somewhat mind boggling to think about. | askscience | http://www.reddit.com/r/askscience/comments/1f4e1v/how_is_the_infrastructure_of_the_internet_built/ | {
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"The \"internet\" is simply a huge network. There are many subnetworks, and subnetworks of those networks, but it all is just a big web of connections. \n\nSome huge telecommunication companies own huge fiber optic cable trunks, and they have an agreement to connect them. The top level ISPs are called Tier 1 ISPs. Tier 1 ISPs are the backbone of the internet, and provide service to huge areas. They then sell space to the lower level ISPs, called Tier 2 ISPs. These are the cable internet providers that you probably buy internet from. Tier 3 ISPs are much smaller and buy from Tier 2 ISPs. They are much cheaper and serve small areas.\n\nEach computer on a network is assigned a certain address, called an IP address. Anybody on your network can access your computer through your unique IP address. Think of it like a home address.\n\nEvery single server on the internet has an IP address. Web servers do, game servers do, chat servers do, FTP servers, everything. It gets kind of annoying to memorize the IP addresses of every server you want to connect to, so DNS (domain name system) was invented. DNS servers basically route a domain name (such as _URL_0_) to an IP address of the server that its on (such as 74.125.239.135). If you want to try it out, go ahead and type in 74.125.239.135 into your browser.\n\nThe DNS root servers are managed by ICANN, which you may have heard of. Sometimes when you want to buy a domain from Godaddy or another registrar, they charge something like a 20 cent ICANN fee. ICANN is basically a nonprofit organization that manages the DNS for the world. You technically don't HAVE to use ICANN DNS servers. You can host your own DNS server and connect to it, and assign as many domain names as you want, but nobody else will be able to go to those domains unless they are using that DNS server."
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cqfp3k | why does english pop up everywhere? like in anime, and foreign music they just say a line in english and then just back to their respective languages. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cqfp3k/eli5_why_does_english_pop_up_everywhere_like_in/ | {
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"Because it's currently seen as the lingua franca of the western world I'd reckon",
"English is the world's most popular second language. Hundreds of millions of people know a little English, enough to understand a word or two thrown into a song for fun.",
"I think it has to do with a couple of things. If it's an English company name, like Apple, they would say the name of the company since it's a Pronoun. Just like we would say Toshiba, for example. The other could be common phrases, like OK or GOODBYE. Just like how we might say Adios or other common phrases in other languages. Sometimes it's just fun!",
"Mostly because there is no word in that particular language for whatever it is they are referring to.\n\nSo for eg, very few languages have a word for rocketship or blackhole. They could use the litteral words to replace them, but that combination probably already exists and means something else.\n\nIf you want to say rap battle in urdu then you're gonna have a hard time. So you would just say rap battle.\n\nLanguage is at the end of the day a tool to express. If your expression is understood, then you won.",
"At different times, different languages are dominate across borders, which shapes other languages. It becomes trendy or profitable to know the dominate language and eventually, it gets ingrained in the other language. Right now, that language is English, but that is relatively recent and in the past English has absorbed other languages in the same way. \n\nWhen you broil beef to serve to the sergeant in the army, you are using a lot of words that came from french - Broil, beef, sergeant, and army all originate from French, which was the \"lingua franca\" of the world for a long time. \n\nWhen someone's husband looks through a window at a cake, you are using a lot of Scandinavian words that came in when the Vikings were trading/raiding England (husband, window, cake). \n\nEven today, we have major loanwords from all over - tsunami, blitzkrieg, kindergarten, schlep, schmuck, fika, hygge, croissant, ninja, baguette, smorgasbord, karate, piste, lego, kaputt, bikini, karaoke, teriyaki, etc. We insert these because we like them and they fit a particular use. Other languages do the same thing, but with English terms. \n\nAnother factor that significantly caused English to be a dominate language was the spread of the English Empire, which at it's height covered a huge amount of the world. More recently, the success after WWII of the US reinforced English as a world language - The occupation of Japan and subsequent preferred trading status to boost their economy caused English to become a major language there and the success of US and British companies in being major players in the oil industry in the middle east was influential in making English (and the dollar) relevant there. \n\nOutside of that, knowing English is profitable in many places and is essential for programming, business, and more. It's a social status indicator in many places and in other places, English is a second language. For example, in the nordic countries, just about every last person is fluent in English today - in 1915, most people spoke German, not English, which represented who they predominately traded with. \n\nSo, basically, it's a prestige language in many places, seen as \"cool\", and English has become the main international language (for the time being)."
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w08c8 | Border Between Portugal and Spain | Why is the border between Portuagl and Spain where it is? I couldn't find any geographical reasons for it; there isn't a mountain range or a big river or anything along the border.
Also, on a related note, why do the two countries speak different languages? I would have thought with a border so porous the people would speak the same language or at most different dialects. Comparing Iberia to France or German speaking areas this seems a little odd. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/w08c8/border_between_portugal_and_spain/ | {
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"Why specifically these borders and not somewhere else is a question that's beyond me, but Portugal, immediately after its Reconquista, was a County and vassal to the Kingdom of Galicia and later Leon. Afonso I of Portugal became independent mostly with papal support due to his role in driving out the Moors in present day Portugal. Since then borders have shifted and wasn't finalized for a few more hundred years.\n\nThe language thing is more clear - Portuguese used to be a lot more like Galician, but in the past thousand years or so they've become more and more different, with Castillan taking hold of the rest of Spain and slowly relegating other Iberian languages like Leonese, Aragonese, Basque, Catalan, and Asturian to secondary status. These languages all have similarities and were a varying degree of difference between Portuguese and Castillan.",
"Borders in Europe will always look \"illogical\" because there's usually about a 1000 years of history behind them.\n\n > Also, on a related note, why do the two countries speak different languages? I would have thought with a border so porous the people would speak the same language or at most different dialects. Comparing Iberia to France or German speaking areas this seems a little odd.\n\nStandard languages are a product of the modern nation-states. In 17th century, villages on the both sides the Spanish-Portugal border would probably speak a very similar dialect. However, in 19th/20th century public education system, press, military service etc. would make them learn 'proper', literary Portuguese/Castillian. "
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53e6b3 | - why do people want ivory so bad and why is it illegal? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/53e6b3/eli5_why_do_people_want_ivory_so_bad_and_why_is/ | {
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"text": [
"Before the advent of plastics, ivory was a very durable alternative to wood. It was considered a luxury good because of its relative scarcity. Most countries have made ivory trade illegal because harvesting it requires killing of endangered elephants."
]
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3m94kc | what is the difference between a credit card reader and a chip-and-pin machine? | Somebody told me that credit card readers are really only used in the US and the rest of the world uses something called a chip-and-pin machine. What exactly is the difference? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3m94kc/eli5_what_is_the_difference_between_a_credit_card/ | {
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"Chip and pin cards look [like this](_URL_0_), where you insert the chip into [the reader](_URL_1_), and are prompted to enter a PIN number (like an ATM) before you can make a purchase.\n\nTraditional credit card readers just [swipe the magnetic strip](_URL_2_), and you sign the receipt.\n\n**Edit**: Added images.",
"Magnetic stripe card readers use the same technology that older computers used to store data on magnetic tape, The magnetic stripe on the credit card just stores the same information as is written on the card but in a format that the computer can read easily. \n\nThe chip on a chip and pin card is a small computer with one job, it stores the same information as the magnetic stripe but it also has a complex encoding system on it, when you put the card into a chip and pin reader it contacts the bank and sends them the id details from the card (basically the long number). The bank knows that the credit card for that account has a certain chip on it, with a secret code and your pin number, the bank then chooses a long random number and does some maths with all the bits it knows and comes up with a final number, the bank then sends the same random number to the chip in your card (via the chip and pin reader) and asks it to do the same maths. If your pin is correct, the chip is the right one, and the secret information on the card is correct, the chip will come up with the same final number as the bank did proving that you have the right card and pin.\n\nNow if someone reads the magnetic stripe on a credit or debit card they can send that information to the bank over and over until you report the card stolen and the bank eventually blocks it. But if someone reads the number sent from the chip and pin reader back to the bank, they only know how to answer for that specific random number sent by the bank. And as the bank will not send that number again they cannot pretend they still have the card."
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"https://paymentdepot.com/wp-content/uploads/2015/08/chip-n-pin.jpg",
"http://moneris.com/help/iwl255_webhelp/images/iwl255_insert_chip.jpg",
"http://cdn.barcodesinc.com/images/models/lg/MagTek/sureswipe.jpg"
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2ni637 | Is there any hard data to suggest that an animal that has killed a human (like the bear on the front page) is actually likely to repeat this behavior? | I was just curious due to the comments in that thread. I know the standard practice is to eliminate animals known to have killed humans, but I am not sure if this is based on anything other than stories and beliefs handed down from a century or so ago.
Thanks! | askscience | http://www.reddit.com/r/askscience/comments/2ni637/is_there_any_hard_data_to_suggest_that_an_animal/ | {
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"Yes there is. Especially if they develop a taste for human meat. Carnivores frequently will attack humans if they are sick, weak, or old. We are quite easy to eat. \n\nabout lions in the 1800's that preyed on Keyan construction Workers _URL_0_ "
]
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| []
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1vw3dn | why is it that the majority of the police officers/military in corrupt states defend the corrupted governments? | I read a comment earlier that hit me pretty hard. It said something along the lines of:
"...as soon as these policemen get off their shift, they are just as oppressed as the rest of the citizens in that state."
So why do they stand for it, then? Why do they defend the corruptness and try to silence the victims of the fallen government?
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1vw3dn/eli5_why_is_it_that_the_majority_of_the_police/ | {
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"text": [
"Cops aren't as oppressed as those they help oppressed. Cops break the law a lot more than your average citizen and their position lets them get away with it. As long as they keep those in power they get to keep their jobs and the perks that come along with it."
]
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4h1ntl | What is the Western Han and Eastern Han in the context of the Han Dynasty? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/4h1ntl/what_is_the_western_han_and_eastern_han_in_the/ | {
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"They are the same dynasty ruled by the same family. The reason why there is the Western Han and the Eastern Han is because in between the two, a man named Wang Mang usurped power from the Western Han emperor and established the Xin Dynasty. After he was defeated and overthrown, the Han dynasty was reestablished in Luoyang (in the east), rather than in the old capital Chang'an (in the west), hence the name \"Eastern Han\". In some texts you might come across Former Han and Latter Han, which is the same as Western Han and Eastern Han."
]
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||
17ns24 | When you rinse out a glass of red wine, why does the water turn gray? | Usually when I clean a glass of red wine in a white porcelain sink, there's a tiny bit of wine in the bottom of the glass. I add some tap water and swirl it around, and it appears like the liquid in the glass has turned a cool gray (and not, say, pink or light red, as one might expect).
What causes this? Is it a chemical reaction with the tap water? Or is it an optics thing where the wine/water is absorbing light of a particular wavelength? | askscience | http://www.reddit.com/r/askscience/comments/17ns24/when_you_rinse_out_a_glass_of_red_wine_why_does/ | {
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"Probably the pH change, which turns the anthocyanidins from their \"native\" reddish/purple color (at the low pH of the wine) to a blue color which, when diluted, looks a bit gray. This is also a decent technique for removing red wine stains: use a cleaner with a higher pH. _URL_0_"
]
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"http://www.demochem.de/p26_anth-e.htm"
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14e6kr | Why aren't we crushed by the weight of the air over our heads? And why don't we feel the weight of the air lifted off of us when we go into a car or building? | In a physics book I had, they solved to find the weight of the column of air above your head. I don't remember the exact value, but it was pretty damn heavy. Why aren't we crushed by this column? And when you go into a car or building, its the roof supporting the air now. Why don't we feel the weight being lifted? | askscience | http://www.reddit.com/r/askscience/comments/14e6kr/why_arent_we_crushed_by_the_weight_of_the_air/ | {
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"[Atmospheric pressure](_URL_0_) is the measure of the amount of force the air exerts on you per area. So it _is_ already measuring the weight of air that exerts on some area. If your room is at one atm, it is pressurized. The weight of air is on you.",
"The reason you don't feel the pressure crushing you down is because there is an equal pressure pushing *up*. Pressure does not work like force, where it can only push in one direction at a time. Because gases (and liquids) are free to move in any direction, pressure pushes equally in *every* direction, so for every pound of force pushing down from above you there is also a pound of force pushing up from below you."
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3t5p53 | why do some people who's parents are immigrants have an accent while others don't ? | I have some friends who's both parents are from other countries but not all of them have their parents native land's accent can you explain it ? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3t5p53/eli5_why_do_some_people_whos_parents_are/ | {
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"Accents tend to come more from peers than parents. So someone who grew up in an area where all the friends and neighbors share the same accent, or perhaps went to a private or parochial school where that was the case, will more likely have a similar accent. But when children go to assimilated schools, especially at the younger ages, they're more likely to get that accent than their parents'. "
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1feum5 | When did winking become a thing? | Examples of histories earliest winks? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1feum5/when_did_winking_become_a_thing/ | {
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"I can tell you the OED's first use of this definition of the word \"wink\" if that's useful at all.\n\n1541 Thomas Elyot's *Image of Gouernance* (Governance)\n\n\"Of a mayster sturdy and fierce, a lyttell wynke to his seruant is a fearefull commaundement.\""
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3d2vj0 | why do we use olive oil instead of frying oil when stirfrying vegetables? | Title. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3d2vj0/eli5_why_do_we_use_olive_oil_instead_of_frying/ | {
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"text": [
"Properly stir-frying anything requires using really high temperatures.\n\nMost olive oil has a relatively low smoke point (the temperature at which it starts to break down & smoke). Stir-fry oils are generally things that handle temperatures better like corn, peanut, canola & soy.\n\nThere's also the bit that olives are not native to Asia, where stirfry recipes are from so the flavor profile of olive oil (which is relatively pronounced compared to many other cooking oils) is a poor match for the types of dishes you'd normally be stir frying."
]
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|
|
3mxjni | why european civilizations were so much more advanced in terms of everything compared to african and native american civilizations. and so when white ppl came to america they basically just took over with guns. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3mxjni/eli5_why_european_civilizations_were_so_much_more/ | {
"a_id": [
"cvj0df1"
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"text": [
"_URL_1_\n\n_URL_0_\n\n_URL_5_\n\n_URL_2_\n\n_URL_3_\n\n_URL_4_"
]
} | []
| []
| [
[
"https://www.reddit.com/r/explainlikeimfive/comments/1o2t90/eli5_considering_that_humanity_and_civilization/",
"https://www.reddit.com/r/explainlikeimfive/comments/115q2q/eli5_why_africa_is_so_underdeveloped/",
"https://www.reddit.com/r/explainlikeimfive/comments/3523y5/eli5_why_did_anglosaxon_white_european_societies/",
"https://www.reddit.com/r/explainlikeimfive/comments/1rdiem/why_is_africa_so_far_behind_in_technology/",
"https://www.reddit.com/r/explainlikeimfive/comments/1pa50z/eli5_why_is_there_such_a_stark_contrast_in/",
"https://www.reddit.com/r/explainlikeimfive/comments/2l9p56/eli5_why_tribal_populations_in_north_and_south/"
]
]
|
||
arrggi | the united states is over $22 trillion in debt. what does that mean? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/arrggi/eli5_the_united_states_is_over_22_trillion_in/ | {
"a_id": [
"egp768t",
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"score": [
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"text": [
"Not a whole lot, actually. Somewhere between 70-80% of that debt is held by American citizens in the form of bonds, including savings bonds. Bonds are heavily used as a stable investment to protect your money from inflation (the rates on the bonds basically keep up with the rate of inflation). And none of the debt is callable, which means that the individuals holding the debt cannot just order to be paid everything due in advance of the payment schedule. \n\nIn effect, as long as the GDP grows at about the rate of inflation, the amount of debt that the US has is stable. If inflation shoots up, or if GDP falls heavily, it can get a little bit tricky. But that's why we've got the Federal Reserve to look out for those things well in advance and take action to mitigate it before it becomes a problem. ",
"The US government is heavily funded by financial instruments such as bonds. In exchange for cash now, the US treasury will give you more cash later. That debt is about $22 trillion.",
"Imagine you have a bunch of credit cards and you owe 22 trillion. This is the United States if it was a person. The only difference is the United States can choose what interest rate it charges itself. Now you might say to yourself, I’ll charge myself 0%, well yes and no. In order to get people to buy your debt (bonds) you need to pay them some interest. Bonds are seen as secure investment by every government in the world because we are seen as a stable economy. Most US citizens by bonds for the same reason, we will get our money back. Now the deficit is meaningless in terms of how much we produce (GDP) but you don’t want it to continually grow long term. "
]
} | []
| []
| [
[],
[],
[]
]
|
||
1sl6ow | what is the bubonic plague, and would it be as fatal today as it was in the middle ages? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1sl6ow/eli5what_is_the_bubonic_plague_and_would_it_be_as/ | {
"a_id": [
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"text": [
"Bubonic plague is a specific kind of disease caused by the bacteria Yersinia pestis. (Pneumonic and septicemic plague are the other kinds, less famous because they didn't destroy Europe.) Yersinia lives in fleas, which live on rodents. As a result, plague was able to spread very quickly in a time when sailors could bring rats across the Mediterranean, and when huge numbers of people lived in crowded, filthy cities where parasites were a normal part of life.\n\nIs it as deadly now? No. Antibiotics have made plague dramatically more survivable, while hygiene in the developed world means you're highly unlikely to get fleas. In fact, when plague was found in squirrels near Los Angeles, the only response was to close a few campgrounds. There are many fine things to worry about, but the Black Death isn't one of them.",
"This is from today\n_URL_0_",
"Bubonic plague actually still exists, and an outbreak in Madagascar was announced just today. It's certainly survivable these days because we understand more about it and have developed effective treatments against it.",
"Survival rates for the bubonic plague with modern antibacterial treatment are 85%-99%. Survival rates without treatment is more like 40%, which is what happened in the middle ages, combined with poor hygiene and wound treatment that made nonfatal side effects significantly more dangerous. I actually knew a guy in boy scouts when I was a kid who apparently contracted it from infected rodents living under his family's cabin or some such. He was treated and suffered no long term ill effects, though I think catching it early is pretty important, as untreated it kills the infected in less than a week, so there's not a lot of time to wait and see."
]
} | []
| []
| [
[],
[
"http://www.reddit.com/r/worldnews/comments/1skdzu/confirmed_outbreak_of_bubonic_plague_in/"
],
[],
[]
]
|
||
8akuip | [Medicine] Improper alcohol detoxification can kill a person. How then can people rehabilitate alcoholics? | askscience | https://www.reddit.com/r/askscience/comments/8akuip/medicine_improper_alcohol_detoxification_can_kill/ | {
"a_id": [
"dx1jtwe",
"dx2wix9"
],
"score": [
4,
2
],
"text": [
"have them (the addict) continue to consume alcohol as needed to avoid serious withdrawal symptoms.\n\nHowever, the amount consumed per day is decreased continually over a span of several days, so that their dependance on ethanol is gradually reduced to zero.",
"Switch to other longer acting drugs that work on the same receptors (diazepam or other benzos) and then taper down the dosage at a safe and tolerable rate. Cold turkey is very rarely an effective method of overcoming moderate-severe cases of physical dependency because even overlooking the risks of seizures and strokes relapse rates are very high due to how psychologically challenging it is to overcome acute withdrawal."
]
} | []
| []
| [
[],
[]
]
|
||
wmfo2 | What is a plausible scientific explanation for "glory clouds" in church services? | I read a NYT article about a runner that relied on his faith. He mentioned something about "glory clouds" during his church service.
Being the skeptical citizen I am I was curious and googled it. I found a few youtube videos of the phenomenon occurring in their church (Bethel Church in Redding, CA).
I googled around to see if there was a debunking and I found nothing more than some suggestions that it was either a malfunctioning in their ventilation system, or a good old fashioned glitter dump.
Are there any reasonable explanations here? Or is trickery at work?
Thanks!
NYT article: _URL_1_
Youtube video (one of many similar): _URL_0_
| askscience | http://www.reddit.com/r/askscience/comments/wmfo2/what_is_a_plausible_scientific_explanation_for/ | {
"a_id": [
"c5ekto4",
"c5ekvfs"
],
"score": [
2,
2
],
"text": [
"That's dust. Definitely dust, you can tell by the straight line it makes coming from the light. ",
"Edit: Probably [This.](_URL_0_)\n\nIt is most likely due to the condensation of water from evaporated sweat and breath. Supposedly if one of Hitler's buildings had been created the amount of people within the room's combined water generation would cause rain. \n\nMost likely in the video the air conditioning system cooled the evaporated water into mist giving the \"glory\" cloud."
]
} | []
| [
"http://www.youtube.com/watch?v=6VqbVH6SNP4",
"http://www.nytimes.com/2012/07/14/business/conflict-potential-seen-in-genetic-counselors-paid-by-testing-companies.html"
]
| [
[],
[
"http://www.valleyvet.com/ct_detail.html?pgguid=9845ba46-7646-4938-a637-357f55afbb73&itemGUID=ac80bab5-c29a-4b58-a228-c1f6dadf4d5b&ccd=ISH002&utm_source=shopping.com&utm_medium=cpc&utm_content=37718"
]
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|
|
301iom | how do cough suppressants, decongestants and expectorants work together to help with a cold? | Most cold medicines have a combo of the 3, and to me it seems counterintuitive to take more than one at a time. For example, why take an expectorant if I'm taking a cough suppressant? Don't i need to cough to get that stuff out? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/301iom/eli5_how_do_cough_suppressants_decongestants_and/ | {
"a_id": [
"cpoa9wg"
],
"score": [
2
],
"text": [
"None of the above help colds. They help the symptoms of a cold. Decongestants, fine. Cough suppressants and expectorants seem illogical if mixed but separately they might help the symptoms. \n\nMany of this type of symptomatic \"cure\" has ingredients that defy strict logic. Despite this, people buy them."
]
} | []
| []
| [
[]
]
|
|
1orquy | What causes the varied distribution of resources across the Earth? | Currently there's debate over mass resources centralized in areas such as the DRC, with some of the sought after minerals being highly concentrated - like Coltan.
Are the natural resources' locations a byproduct of random accumulation when the Earth was formed, or are other contributing factors the cause (i.e. meteoroids and other foreign body collisions). | askscience | http://www.reddit.com/r/askscience/comments/1orquy/what_causes_the_varied_distribution_of_resources/ | {
"a_id": [
"ccuynri"
],
"score": [
3
],
"text": [
"It's not a random process. Certain minerals only form under a set of very precise geological conditions. Much like how you need just the right ingredients to make a cake, you need just the right conditions to produce certain types of rock. These conditions include depth below the surface, temperature, pressure, local rock composition, hydrothermal activity, volcanic-tectonic activity. If you happen to get all these factors just right, then a body of ore will form. An understanding of what conditions produce what types of ore is useful to geologists who predict the locations in which to search for ore."
]
} | []
| []
| [
[]
]
|
|
16ddlo | How did Italian-Americans react to the extremely racist Allied anti Axis propaganda films? | Just wondering, greatly thankful for any answers. God bless.
| AskHistorians | http://www.reddit.com/r/AskHistorians/comments/16ddlo/how_did_italianamericans_react_to_the_extremely/ | {
"a_id": [
"c7v15wm",
"c7v2u03",
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"score": [
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"text": [
"You're referring to American films? Or is that incorrect? If so, I apologize. \n\nTo answer the question to the best of my ability, most Italian-Americans realized by 1939 that Benito Mussolini wasn't a champion of the people of Italy. But, more and more, he appeared to be a cancerous tyrant who wanted to create a \"New Roman Empire\" (and therefore subjugate/enslave millions of people). \n\nSo, the very biased films produced in America weren't all that offensive to them. The majority of Italian-Americans despised the man by the time WWII started. ",
"Can we broaden this to include Asian Americans?",
"Anti-Italian racism had existed strongly in the US during the years of large-scale Italian immigration in the late 19th and early 20th centuries. The prevailing American view of Italians during the early 20th century was that Italians were inferior (some thought permanently racially inferior, others thought mostly culturally inferior), low class foreigners whose lack of education and Catholic religion made them unfit for American citizenship. During the WWII era, Americans did not develop a racism towards Italian-Americans that had not existed before.\n\nWWII propaganda primarily demonized the Japanese, then the Nazis, and only occasionally the Italians. In addition, WWII propaganda more often portrayed Italians as incompetent cowards than as inhuman villains like the Japanese and Nazis. \n(Source: Peter Schrag's \"Not Fit for Our Society\")\n\nAlso, I will point out that unlike the US's interment of all west coast Japanese Americans based on race alone, the wartime treatment of Italian and German Americans was based on individual selection and investigation.\n\nFor example, immediately following Pearl Harbor, the US Justice Department arrested 1,393 German nationals, 264 Italian nationals, and 2,192 Japanese under the authority of the Alien Enemy Act and Roosevelt's Executive Order 9066. These people had been under surveillance by the FBI as potentially dangerous, and were sent to regional detention facilities where individual loyalty hearings were conducted. The Justice Department released most of the Germans and Italians, but the Japanese (who comprised most of the business, social, cultural and political leadership of Japanese American communities) either remained in detention camps or were \"paroled\" to Japanese internment camps.\n(Source: Mai Ngai's \"Impossible Subjects\")\n"
]
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| []
| [
[],
[],
[]
]
|
|
2ogz05 | The ratio of the distance between a planet and its star vs the ratio of the distance between an electron and its nucleus, are the two ratios similar? | askscience | http://www.reddit.com/r/askscience/comments/2ogz05/the_ratio_of_the_distance_between_a_planet_and/ | {
"a_id": [
"cmn1323"
],
"score": [
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],
"text": [
"Compared to the radius of the sun, the Earth is 215 times farther away.\n\nCompared to the radius of a proton, the average position of the ground state hydrogen electron is 62,350 times farther away.\n\nNow, there are other planets and stars and other elements, but that gives you a rough picture."
]
} | []
| []
| [
[]
]
|
||
h6htd | Considering all dogs have 38 chromosomes, can a very small dog mate with(in some manner) and give birth to a very large dog's pups? | askscience | http://www.reddit.com/r/askscience/comments/h6htd/considering_all_dogs_have_38_chromosomes_can_a/ | {
"a_id": [
"c1sye2q"
],
"score": [
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"text": [
"A family member of mine breeds dogs so I've seen newborn puppies firsthand. There were two simultaneous litters of puppies; one from a toy poodle, and one litter from a standard poodle. What was amazing is that these newborns were practically the same size, just the toy poodle had considerably less (2) than the standard who delivered 13. Humans have been able to alter the appearance and behavior of dogs but we have not so much affected their reproduction.\n\nThus, the small dog will deliver puppies of the \"standard puppy size\" which is about 3-4 inches which will then grow into dogs much larger than the bitch.\n\nEdit for clarity: We - > Humans"
]
} | []
| []
| [
[]
]
|
||
1jc7wr | why are vishnu and his avatars blue? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1jc7wr/eli5_why_are_vishnu_and_his_avatars_blue/ | {
"a_id": [
"cbd7xt2"
],
"score": [
2
],
"text": [
"Blue is considered a divine/pure colour. \nI.e. connected to the sky / the sea"
]
} | []
| []
| [
[]
]
|
||
1kvd7u | How long can a plant survive in space? | I was just re-watching Wall-E and there is this scene where Wall-E and Eve are flying around in space with their plant.
It got me wondering, can a plant be exposed to space at all? And if so, for how long?
| askscience | http://www.reddit.com/r/askscience/comments/1kvd7u/how_long_can_a_plant_survive_in_space/ | {
"a_id": [
"cbsz6t1"
],
"score": [
5
],
"text": [
"Depends on the environment. Plants can grow in microgravity with an artificial atmosphere, but if you're just talking about throwing a naked plant into space, the extreme temperatures would start rupturing cells immediately (areas in the sun would be very hot, and areas in shade would be well below freezing). Between these two extreme temperatures and the very low pressure, which would also accelerate the rate at which volatiles boiled off, the plant would start to die as soon as it was exposed to this type of environment. How long is likely a function of the species and plant size."
]
} | []
| []
| [
[]
]
|
|
3riw90 | Why were brass knuckles made of brass? | I imagine that steel or even iron would be cheaper and more effective, and less prone to damage or wear. | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/3riw90/why_were_brass_knuckles_made_of_brass/ | {
"a_id": [
"cwoir0x"
],
"score": [
6
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"text": [
"I can't speak to the historical aspect but from an industrial aspect brass is pretty inexpensive and is usually cast in a mold. Forged steel would be much more labor intensive. Cast iron would be subject to rusting. Brass is a good tradeoff of strength, cost, and corrosion resistance."
]
} | []
| []
| [
[]
]
|
|
b9wwcw | why did ants ( and other insects maybe idk) get an exoskeleton rather than a normal skeleton? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b9wwcw/eli5_why_did_ants_and_other_insects_maybe_idk_get/ | {
"a_id": [
"ek7hjqf",
"ek7ldsl"
],
"score": [
6,
3
],
"text": [
"Because a hard outer shell doubles as protection from predators, as well as anchor points for muscles.\n\nEndoskeletons evolved to provide otherwise soft-bodied animals leverage to generate more power in their appendages without sacrificing as much flexibility as an exoskeleton.",
"Insects are part of a larger group of animals called Ecdysozoa, all of which have the ability to shed the outer layer of their skin, or cuticle. Though some members of the Ecdysozoa are still somewhat soft-bodied, like [roundworms](_URL_3_), one group developed a much harder and more inflexible outer cuticle with segments and jointed limbs to allow some movement. This group, the Arthropoda, contains most animals we think of as having exoskeletons, including the extinct [trilobites](_URL_0_), as well as the still living [chelicerates](_URL_4_) (most of which are arachnids), [myriapods](_URL_8_) (centipedes and millipedes), and pancrustacea (which consists of crustaceans as well as insects, which are [nested inside crustaceans](_URL_6_)).\n\nPresumably, the exoskeleton in arthropods developed as a form of protection against predators, but it's hard to be completely sure, since it first appeared in the ancestors of this group which lived over 500 million years ago. The benefits of this kind of protection are obvious, and importantly, the preexisting ability to shed their skins allowed them to continue to grow larger over their lives, and even regrow lost body parts. Having a tough outer covering also helped arthropods like [*Pneumodesmus*](_URL_5_) to become the first animals to colonize land, tens of millions of years before vertebrates would ([source](_URL_7_)). Interestingly, though earlier arthropods probably shed their skins regularly throughout their lives (as many still do today), the majority of insect species no longer do this, and instead have a finite number of moults they go through as they grow before reaching a final and permanent adult stage.\n\nAs opposed to arthropods and other ecdysozoans, the ancestors of vertebrates (the earliest of which lived around the same time as the first arthropods \\~500 million years ago, like [*Haikouichthys*](_URL_2_)) were relatively soft and did not shed their skins. However, they did have rigid internal structures like notochords made of cartilage-like materials, which allowed them to swim effectively using full body [movements from side to side](_URL_1_). Eventually, bones developed from cartilage in vertebrates, leading to the internal skeletons we have now."
]
} | []
| []
| [
[],
[
"https://static01.nyt.com/images/2014/03/04/science/trilobites-1393889944421/trilobites-1393889944421-videoLarge.jpg",
"https://images.slideplayer.com/14/4427902/slides/slide_11.jpg",
"https://i.pinimg.com/originals/02/19/83/021983b5aef75ae3287aa4384a9d1f1d.jpg",
"https://ucmp.berkeley.edu/phyla/ecdysozoa/nematoda.html",
"https://www.researchgate.net/profile/Prashant_Sharma18/publication/326569287/figure/fig1/AS:652419352498176@1532560303089/Examples-of-chelicerate-diversity-Left-column-top-Isometrus-sp-Scorpiones-Left.png",
"https://i.dailymail.co.uk/i/pix/2017/07/05/23/421115C200000578-4669222-image-a-72_1499294547822.jpg",
"https://whyevolutionistrue.wordpress.com/2010/03/04/insects-are-crustaceans-2/",
"https://www.academia.edu/891357/Early_terrestrial_animals_evolution_and_uncertainty",
"https://upload.wikimedia.org/wikipedia/commons/thumb/e/e7/Myriapod_collage.png/1200px-Myriapod_collage.png"
]
]
|
||
2ye88c | do people who talk languages other than english think in those languages? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ye88c/eli5_do_people_who_talk_languages_other_than/ | {
"a_id": [
"cp8otxn"
],
"score": [
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"text": [
"Do you think in English?\n\nSeriously, when you think of a dog running across a field, do you imagine those words \"a dog running across a field\"? Or do you imagine an actual dog running across an actual field?\n\nThe only times that we actually think in words, is when we are thinking of a language. I could think \"My name is Thomas\" in those words, I could also think \"Je m'appelle Thomas\", or I could think in the abstract sense that Thomas and myself are one in the same.\n\nIt's similar to \"how do deaf people think?\""
]
} | []
| []
| [
[]
]
|
||
6sfpj2 | How is corruption measured? | [deleted] | askscience | https://www.reddit.com/r/askscience/comments/6sfpj2/how_is_corruption_measured/ | {
"a_id": [
"dlcf61a",
"dlck829"
],
"score": [
2,
57
],
"text": [
"Here's the sources for the Corruption Perception Index of 2016:\n\n_URL_0_",
"Transparency International publishes what they call a \"Corruption Perception Index\" made up from polls. They ask people how often in the past year (or whatever timeframe) they paid a bribe, and how much, and in what situation. \nIt is true that the data is not entirely reliable because of the very nature of the thing but they openly acknowledge this. \n\n[From their Website:](_URL_0_)\n\n > WHY IS THE CPI BASED ON PERCEPTIONS?\n\n > Corruption generally comprises illegal activities, which are deliberately hidden and only come to light through scandals, investigations or prosecutions. There is no meaningful way to assess absolute levels of corruption in countries or territories on the basis of hard empirical data. Possible attempts to do so, such as by comparing bribes reported, the number of prosecutions brought or studying court cases directly linked to corruption, cannot be taken as definitive indicators of corruption levels. Instead, they show how effective prosecutors, the courts or the media are in investigating and exposing corruption. Capturing perceptions of corruption of those in a position to offer assessments of public sector corruption is the most reliable method of comparing relative corruption levels across countries."
]
} | []
| []
| [
[
"http://files.transparency.org/content/download/2056/13236/file/CPI_2016_SourceDescriptionDocument_EN.pdf"
],
[
"https://www.transparency.org/cpi2014/in_detail"
]
]
|
|
80u2q7 | what happens to the food company when someone who is allergic to a secret ingredient consumes their food? will it be revealed? why has it not ever happened? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/80u2q7/eli5_what_happens_to_the_food_company_when/ | {
"a_id": [
"duy7oxk",
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"score": [
5,
2
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"text": [
"I think due to FDA regulations all ingredients must be listed, so the secrets are usually formulas and combinations. But the individual ingredients that people may be allergic to are listed. ",
"there's a list of specific allergens that must be listed if it's in the food or if the food could come in contact with that. other than that, everything's fair game. only prepacked products are subject to fda labeling requirements. other than that, it's up to the eater to due their diligence. "
]
} | []
| []
| [
[],
[]
]
|
||
3j0cns | if it is illegal to melt down pennies, how is it legal to press them? | I started looking at my small collection of squashed coins, and it made me think. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3j0cns/eli5_if_it_is_illegal_to_melt_down_pennies_how_is/ | {
"a_id": [
"cul7o2w"
],
"score": [
9
],
"text": [
"Are you talking about how it's legal for the US Mint to press them? Because they're authorized by law to do so.\n\nIf you're asking about those novelty machines that strech out a penny, it's because defacing the currency for non-fraudulent purposes isn't illegal."
]
} | []
| []
| [
[]
]
|
|
3k85qd | why the american corn taste different from middle eastern corn or asian one? | When i came to usa i tried to taste the american corn from mijier, ( i never tried anything from supermarket so i wouldnt know) and it taste sweet and different. I didnt like it. To me it is not delicious. Ahs ever been like this forever? Or something changed in the middle? Or is it that i am just baised and used to my country food? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3k85qd/eli5_why_the_american_corn_taste_different_from/ | {
"a_id": [
"cuvgswj",
"cuviep9",
"cuvkdqp"
],
"score": [
9,
7,
2
],
"text": [
"They differ in species, soil composition, environment, exposure to the sun. These all could effect the taste.",
"There are many different variations of corn. In Korea (s), supermarkets usually have 2 or 3 different corns in the vegetable section (starchy, sweet). In the US, it's usually the same sweet corn, unless you have a large farmers' market.",
"the corn can only build itself from whatever nutrients it can obtain.\n\nif you plant something in another soil that has different properties these properties will change the plant.\n\nafter a few generations of this your plant will evolve to better cope with the changed soil conditions (with assistance of the farmer who seeks to maximize his yield), resulting in \"different\" corn."
]
} | []
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| [
[],
[],
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|
|
7aguu2 | what's the difference between tense, mood, and case? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7aguu2/eli5_whats_the_difference_between_tense_mood_and/ | {
"a_id": [
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"text": [
"Tense is the time of the action, past, future, happening right now. The tenses give a sense of when an action was completed, or if we expect the action to continue into the foreseeable future. It puts the verbs into a context of when. \n\nMood adds or removes a certain certainty or uncertainty or more commonly, obligation. We use modal verbs to add a stronger sense of obligation (must, have to) or soften a statement to suggestion (should). We don't really moods in English because we use these modal verbs, if you study Italian then you'll see mood a lot use with different verbs - \"essere\", to be, changes to \"sia\", for example, the actual verb \"to be\" changes the mood of the sentence, in English we add \"should\" and leave the next verb alone \"he should leave\". \n\nCases you'll see a lot in German, which is when the pronoun changes depending on who is doing what to whom. We have them in English too, but not to a greater degree as in German. For example, you don't say \"I'll give the bucket to he\", you say \"I'll give the bucket to him\". The possessive is \"his bucket\" - the cases that we have in English mean that you must change \"he\" to \"him\" and \"he\" to \"his\" depending on who is doing what to what/with what object. He is 'owning' his bucket\". \n\nThis is my understanding of it, at least, having taught English for 10 years and studied Italian, German and French. "
]
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| [
[]
]
|
||
b15c9b | if peanuts aren't actually nuts why do people with a nut allergy die from them? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b15c9b/eli5_if_peanuts_arent_actually_nuts_why_do_people/ | {
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"text": [
"Because peanut allergies are different from nut allergies. I'm allergic to peanuts but not nuts. "
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| []
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[]
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|
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55hnmh | why does my cat retain the ability to bound at 30 mph and jump vertically 5ft if he sleeps all day? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/55hnmh/eli5why_does_my_cat_retain_the_ability_to_bound/ | {
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"I assume your cat, like almost every cat, likes to jump up on things and tends to go bat-shit crazy in the middle of the night and run around like a maniac sometimes. This is its exercise. \n\nCompare that to a reasonably fit human that works out regularly - not a gym nut or anything but just a guy who works out like twice a week to stay healthy and fit. He'll probably work out for what, a couple of hours? And that won't be nonstop, it'll be in sets with frequent breaks. So in reality he spends less than 30 minutes actually exercising, and he does that twice a week. So less than an hour per week exercising and he's perfectly fine.\n\nTL:DR You only need to exercise a little to maintain your muscles.",
"Other animals don't need to \"work out\" to stay strong. Humans lose muscle because it helps us reduce calorie needs if we're not using those muscles. Hence why you can go 30 days or so without food and still survive (in decent conditions). Look at how strong gorillas are, they literally sit around all day just eating grass or whatever. They're not banging out push-ups on the side or anything. \n\nSource: some askscience thread I read a few months ago I think ",
"There is evidence to show that it might be related to purring - they purr as a form of self healing and to keep their muscles toned: _URL_0_",
"They have explosive energy stores so they don't exercise heaps.\n\nThey exercise in short bursts throughout a 24 hour period.\n\nEg cat goes crazy at night and hunts during the day for like 20% and sleep the rest.\n\nEg2 my dog sleeps all day but will run around the yard when i let him out first thing in the morning. I take him for walks but it is as much for me as him.",
"Every species maintains a certain natural muscle mass. Obviously if you go to extremes you can either lose most of it (muscle atrofy, ever had your leg/arm in a cast for a few months?) or gain a lot more (like bodybuilders). The \"natural state\" is determined by our DNA.\n\nAs an example, look at these two animals:\n\nThe [Belgian Blue cattle](_URL_2_) maintains an enormous amount of muscle mass despite leading a rather stationery life. It was selectively bred for beef. The Belgian Blue has a mutation that prevents Myostatin from inhibiting muscle growth. Because of the amount of muscle it has, it devours extreme amounts of food but that's not a problem because humans feed it.\n\nThe [Gibbon](_URL_0_) maintains a relatively low muscle mass despite leading a rather active life. It's Myostatin is working just right - preventing excessive muscle growth when it's moving a lot.\n\nThe amount of muscle mass an animal has is in it's perfect ratio - enough to move, jump and do stuff but not too much, because it would have to eat a lot more. Muscle atrophy, on the other end, only occurs when there's hardly *any* movement, not just little movement.\n\nA great example of this is bodybuilding. You can lose a lot of muscle very quickly if you stop working out but at a certain point (the natural state of human muscles) that loss will stop as long as you walk around and do stuff. Only the excess is lost quickly. That's also why you can sit at a computer for 10 hours a day without atrophy. [This graph illustrates it.](_URL_1_)\n\nHumans have evolved to use our brains more than our muscles so our natural state is just enough to walk around and run for a few hundred meters at 10 km/h. Cats still rely on muscles a lot so their natural state is just enough to jump around and run fast.\n\nEDIT: Fixed link. EDIT2: Spelling."
]
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[],
[],
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"https://www.scientificamerican.com/article/why-do-cats-purr/"
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[],
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"http://kids.nationalgeographic.com/content/dam/kids/photos/animals/Mammals/A-G/gibbon-tan-18778051.jpg",
"http://i.imgur.com/jz1kBTb.png",
"http://www.tvagro.pl/data/catalogue/belgian-blue.jpg"
]
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|
||
37tihf | why don't we just use two or more different antibiotics, with different ingredients to kill off 100% of bacteria | If they really do kill 99.9% of all bacteria and we use like 5 different kinds of antibiotics wouldn't the chances of them surviving and resisting all those antibiotics be very slim? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/37tihf/eli5_why_dont_we_just_use_two_or_more_different/ | {
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"text": [
"Well antibitoics don't all target the same things. But even if the did, it would be a terrible idea to try. Because if any of the bacteria live? They now have a resistance to all of those antibiotics, instead of just one or two.",
"We do. Antibiotic cocktails are quite common when resistance is suspected. But as /u/sablemint notes, any survivors - and there are likely to be some - then develop resistance more quickly.",
"Not trolling, but your question is too general. Bacteria exists in so many different places, inside your body and outside your body. Not all bacteria are harmful to humans, in fact some are beneficial. If you killed off all the bacteria in or on the human body, then fungus would take over the surface area inside and out, because bacteria are no longer present to compete for food. Then you would have a fungal infection and that can kill you as much as a bacterial infection. Here's a link to a 12 minute video that might help you out.\n _URL_0_",
"Simplest answer: most bacteria is in no way harmful to you. A decent amount is actually helpful. If we killed off all bacteria, we'd lose our ability to digest food (or at least make it a lot less comfortable)\n\nSo even if we could, it would be a very bad idea. In other news, most forms of radiation are also harmless."
]
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[],
[],
[
"http://youtu.be/vAR47-g6tlA"
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[]
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1ebayp | how do different sound waves of the same wavelengths carry a different timbre? | I understand how different wavelengths create different pitches and that different materials, densities etc. can create a different timbre. I just don't understand how two sound waves of the same length could carry them.
Thanks. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ebayp/eli5_how_do_different_sound_waves_of_the_same/ | {
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"text": [
"The shape of the wave affects its sound, or timbre.\n\nThere are some examples [here](_URL_0_). (I don't think the instrument names next to the waves are correct... but it gives you the right idea.)",
"There is a big difference between 'wavelength' and 'pitch'.\n\nAll sounds are made up of many pure sine waves overlaped on top of eachother. A pure sine wave is what you here when you strike a tuning fork. \n\nPitch means a note, like C# or D. Each note corresponds to a specific wavelength. But again, the sounds you hear in every day life are made of many of these wavelengths mixed together. \n\nSomething you perceive as a note with a specific pitch is a mixture dominated by a specific wavelength. But, there is still a whole mix of other wavelengths on top of that. That extra mixture is what makes a C# on a piano sound different than the same C# on a flute.\n\nA sound without a specific pitch, like a crashing wave, has a pretty much even mixture of all wavelengths. This is also know as 'white noise' as analogous to white light.\n\nTo carry the analogy further, light you see is a mixture of wavelengths of color. All images are a mixture of wavelengths in different positions just like all sounds are mixtures of wavelengths at different times. This is why a red truck looks different than a red apple; even though they have the same dominate 'tone'.\n\nIf you are interested in explinations which are math intensive and outside the scope of eli5, check out [Fourier Transforms](_URL_0_)\n\ntl;dr \"two sound waves of the same length\" cant carry different sounds, you need a mixture of many different wavelengths."
]
} | []
| []
| [
[
"http://library.thinkquest.org/5116/images/soundwave3.GIF"
],
[
"https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CC4QFjAA&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FFourier_transform&ei=lJSSUa_RGIywqwGu84HgCw&usg=AFQjCNEltUQRoKWb8sbIpb_7BHJdQTUmQg&sig2=h2hj0Ass5-_MYmMnOGgGOQ&bvm=bv.46471029,d.aWM"
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3ayhxa | Were torches used in medieval times as much as movies make us believe and what were they made out off? | and how functional were they? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/3ayhxa/were_torches_used_in_medieval_times_as_much_as/ | {
"a_id": [
"csh5xan"
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"text": [
"Were torches used as often as we see in movies?\n\nNo. Movies generally seem to show torches as the most common light source for medieval people, when in fact rushlights (reeds soaked in animal fat), tallow candles and simple oil lamps seem to have been much more common.\n\nWhat were torches made of?\n\nUsually a wooden handle (possibly with some metal fittings), some kind of fibre to act as a wick and oil or fat to serve as fuel (apparently some of them used other forms of fuel, like sulphur and pitch, which seems even less practical). The fibre is soaked in the fuel and either wrapped around the handle or stuffed inside, depending on the design.\n\nHow functional were they?\n\nBased on modern reconstructions, not very. They are heavier and more difficult to carry than other forms of lighting, they can't be conveniently put down on a flat surface as most alternatives can and the light they produce is very flickery and difficult to see by. The only benefit seems to be that they are fairly easy to make and less prone to being blown out than a rushlight, which is the other simple-to-manufacture medieval light source."
]
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[]
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900fcz | why do monotonous noises (like the sound of an alarm clock) begin to sound like it has two different pitches after hearing it for a while? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/900fcz/eli5_why_do_monotonous_noises_like_the_sound_of/ | {
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"e2mt9ea"
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"text": [
"i think that it may be because of our natural tendency to turn repetitive sounds into melodies. So a repetitive sound gets given different pitches by our brains. Its called the speech to song illusion. "
]
} | []
| []
| [
[]
]
|
||
8h9hve | how come many fish were able to survive the great k–pg extinction, but pretty much no sea reptiles (mosasaurs, plesiosaurs, etc) were able to? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8h9hve/eli5_how_come_many_fish_were_able_to_survive_the/ | {
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"text": [
"It takes a LOT of food and a very balanced ecosystem to keep a giant alpha predator alive. If the food diminishes or the ecosystem shifts, alpha predators die out pretty easily.",
"Another additional reason. Reptiles are dependent on the surface for air. Fish down deeper might have survived and later expanded and speciated to fill the missing niches near the surface."
]
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2w5p7r | how do bank errors leaving customers with extra money happen? | I always see articles where people report to have massive amounts of money 'accidentally' deposited into their accounts. For example- [this article](_URL_0_).
My grandmother last week also had an extra $1000 given to her in cash, which she had to return to the bank.
My question it- how does this happen? I always assumed banks had incredibly strict systems which would prevent this sort of thing. Does someone actually lose money as you gain it- or does the bank just 'create' an extra amount due to math errors?
Also- if you did withdraw and use the money completely, how is this against the law? I get that it is not your money, but it was the bank's error. Is there any way to keep some of it? If you discovered a fortune in your account, what would you do? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2w5p7r/eli5how_do_bank_errors_leaving_customers_with/ | {
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"I have this saying: \"As long as humans are involved, there will be human error.\" \n \nSimple as that - someone at the bank done goofed. You are right - banks *do* have incredibly strict controls to prevent errors, but as long as human beings are punching keys and inputting information, there's going to be human error on occasion. \n \nI remember one time a customer called in to say that he noticed he had an extra $50,000 in his account, wondered where it came from. Did some digging around through our systems, and figured it out. A third party had walked into a branch to make a deposit into his friend's account, didn't have the account number handy so the teller looked it up by the account holder's name. Even though it was a fairly uncommon name, our bank had *two* customers with the same name. Guess where the money went? \n \nIt was an easy enough fix, and it did not cause any problems with the other customer, but it is still clearly a bank error. Very, very rare (I've seen it maybe twice), but it does happen. \n \nAnother more common error I see is \"check encoding errors\", where someone is manually typing in the information from the checks and types in some digits wrong - such as transposing two numbers, and the money ends up in the wrong account. I see that a few times a year. \n \nBasically, as long as human beings are part of the process of handling the transactions, there will be errors. The error rate is extremely low, but our bank processes several billion individual transactions each day, so a few creep into the system here and there. \n \n > Also- if you did withdraw and use the money completely, how is this against the law? \n \nWell, no, you can't keep it. In the terms and account agreements that you agree to when you open your account, there are disclaimers about bank errors. Pretty much every bank, credit union or financial institution will have a disclaimer about the bank's ability to make corrections, and that you would be responsible for returning any misapplied funds. "
]
} | []
| [
"http://www.bbc.com/news/world-asia-pacific-15129689"
]
| [
[]
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|
|
2nhgjt | Did European explorers/settlers encounter any Native American urban centers in the in modern-day USA and Canada? | I've picked up that the northern Native Americans such as the Pueblo Indians had urban centers, but I'm not sure what happened to them or if non-Native Americans ever encountered them. were they depopulated by disease before settlers got that far? If settlers did encounter urban centers, how did they fit them into their 'this land is not being used properly' rationalizations? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2nhgjt/did_european_explorerssettlers_encounter_any/ | {
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" > the Pueblo Indians had urban centers, but I'm not sure what happened to them\n\nMany are alive and well. Consider Acoma Pueblo and Taos Pueblo, both of which were founded around 1000 years ago and both currently home to between 4500 and 5000 people. Others didn't survive, such as Hawikuh - an old Zuni pueblo that was the first to encounter Coronado's *entrada*. It was one of the legendary Seven Cities of Cibola, which the Spanish believed to have reserves of gold to rival the Aztecs and the Inca (but were sorely disappointed when they actually arrived). The Spanish held it for a time, but eventually abandoned and has now become a ruin. Even at its peak, however, its population estimates are considerably lower that modern Acoma and Taos. But the Southwest isn't my area of expertise so I'll leave a more detailed discussion of that area to others.\n\nInstead, let's turn our attention east.\n\nWhile Coronado was marching through the Southwest, de Soto was [snaking his way through the Southeast](_URL_1_). Along the way, he encountered several prominent Mississippian polities. Among them were the Apalachee, which I'll get to in a moment, and Coosa. \n\n##**COOSA**\n\nTo discuss Coosa, I'm going to introduce you to two Muscogee terms (anglicized a bit for ease of reading): italwa (*etvlwv*) and talofa (*tvlofv*). An italwa is major political center and all its subsidiary elements (by extension, it also refers to a nation and its people). A talofa is town or city in the physical sense - its buildings and its boundaries. Coosa was both. \n\nAs an italwa, it was perhaps the most extensive in what's now the US at the time of European contact. It stretched some 400 miles long. If you refer back to the map, it bordered the Chiscas to the northeast, and its southwestern limit was Talisi (which the neighboring Atahachi italwa was trying to bring into its own sphere of influence as de Soto came through). It was a large and populous nation, with many large towns surrounded by extensive fields of maize and beans, stream-side vineyards, and plum orchards. It was the heir, and probably a direct continuation of, the older Etowah italwa (which is rather redundant actually, since the name \"Etowah\" is derived from *etvlwv* as well), which had been based nearby. I marked their locations on [GoogleMaps](_URL_2_) for you. The location of the Etowah talofa is clearly labeled, with the Coosa talofa is now submerged by a reservoir. \n\nSince I haven't been able to find a decent reconstruction of Coosa, I thought I'd show [this reconstruction](_URL_0_) of its predecessor. The reconstruction of the Etowah talofa gives you an idea, in general, of what Coosa talofa would have looked like when de Soto arrived, but the specifics would have been different of course. In particular, the Etowah reconstruction is much more sparsely populated than Coosa was (and likely more sparsely populated than Etowah actually was too). The population estimates for the Coosa talofa at the time of de Soto range from 2500 to 5000, with the population for the whole italwa at 50,000+. Like Etowah, Coosa had a plaza surrounded by three igan halwa (*ekunhvlwv*), or \"mounds\" if you want the more familiar term. It had at least two distinct districts. One for the common people, and another for the elites. The elite district was built later, at the same time the Etowah talofa was abandoned, which is why it appears that Coosa is the direct continuation of the Etowah italwa - it just moved its capital. Unlike Etowah, Coosa did not have elaborate defensive structures like the palisade walls or moat. When the italwa's capital moved, its leadership must have felt secure in their hegemony over the region and deemed such defenses unnecessary (this was not true for the up-and-coming Atahachi italwa to the southeast, where most of the talofa had defensive fortifications).\n\nThe micco (*mekko*, or \"chief\") of Coosa when de Soto arrived was described as an erudite and cultured man in his mid-20s. He had an air of sophistication about him that reminded the Spanish of the nobility of Europe. Despite his cooperation with the Spanish, he and many of the other high-ranking members of Coosa society were taken captive. This caused a panic in the talofa, as well as the neighboring talofa. The people fled, but the Spanish pursued and captured many of them. The micco negotiated the release of most of his people, but he, his sister, and a few of the prominent members of Coosa society remained captives and were forced to escort de Soto and his men through the remainder of the Coosa italwa. Once they reached Talisi, the micco and most of the other nobles were freed, but de Soto kept the micco's sister. Her fate is unknown, though she either escaped or, more likely, died at the Battle of Mabila that happened shortly thereafter.\n\nAfter de Soto, about a century goes by before there's additional European contact with Coosa. By this time, its power had waned considerably. It was no longer a great italwa stretching along the southern Appalachians. Instead, it had allied three other italwas in the area to form the Mother Towns of the Creek Confederacy."
]
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"http://i.imgur.com/LI2TFZN.jpg",
"http://upload.wikimedia.org/wikipedia/commons/b/bc/DeSoto_Map_HRoe_2008.jpg",
"https://www.google.com/maps/dir/Etowah+Indian+Mounds+Historic+Site,+813+Indian+Mound+Rd+SE,+Cartersville,+GA+30120/'34.59958,-84.68021'/@34.3675481,-85.094075,10z/data=!3m1!4b1!4m11!4m10!1m5!1m1!1s0x88f54f2d28d88a67:0x9dc78925cffab5f2!2m2!1d-84.807061!2d34.128009!1m3!2m2!1d-84.68021!2d34.59958"
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45gr6y | why does light/sound propogate as a wave? why not a straight line? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/45gr6y/eli5_why_does_lightsound_propogate_as_a_wave_why/ | {
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"text": [
"They both do propagate in a straight line just as a wave in the water does. A sound wave or water wave is a varying pressure, not space. And luckily google gave me the answer [from Reddit](_URL_0_) on what varies in a photon: \n\n > The wave is not the path that the photon takes. The wave is a representation of the electromagnetic field associated with that photon.",
"It travels as both, sorta. \nSo there's only a little chance this will be actually understood by a five year old. \nLight (and all energy, therefor matter itself) travels as a probability. What's that really mean though? It means that when you aren't looking at something, there's a chance that it might not exist. For large objects, this chance of not existing is extremely, extremely small. For smaller quantum-level objects, this chance varies. For example, the electrons around a nucleus of an atom exist in certain formations based off which element we're talking about. [See this picture](_URL_1_). These \"areas\" are really just higher probability of the electron existing in that specific region. \nA good thought exercise on this is the ol' [Schrödinger's cat](_URL_0_) thought experiment. Essentially, the cat exists in all viable states (Alive and Dead) at the same time until it is actually observed. When it is observed, the wave function collapses into reality. This really makes no logical sense with something this size. Go down into the smaller level, and it is a very real (and scientifically proven) scenario. \nTake a gander at the [Double Slit Experiment](_URL_3_) for a great example. This [video](_URL_2_) is a good one. The summed up version of that is: Electrons fired through a slit would act as a wave when not being observed. When being observed, they acted like a particle. What really was happening was happening was that the light existed as a wave of probability until it was observed, which then caused it to collapse into a particle. \nThat's my basic understanding of the whole thing, so if any experts exist on there and want to provide some corrections to my answer, please do!",
"Think about it like this:\n \n . . . ... . . . . . . . ... . . . . \n\nThe dots are arranged in a line, yet they carry the information of a wave. When you put them at all angles of a sphere, they represent waves of pressure in 3D. I don't know if this analogy works for light, so keep that in mind."
]
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[
"https://www.reddit.com/r/askscience/comments/2yn2o5/if_photons_travel_along_waves_with_varying/"
],
[
"https://en.wikipedia.org/wiki/Schr%C3%B6dinger%27s_cat",
"http://imgur.com/QaAunvr",
"https://www.youtube.com/watch?v=fwXQjRBLwsQ",
"https://en.wikipedia.org/wiki/Double-slit_experiment"
],
[]
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|
||
4kaii4 | are there gradual forms of depression or is it purely binary? | Specifically, if somebody is generally pessimistic, does it imply that they may just have some very light form of depression, or is that just in the normal realm of human behavior. I'm not asking, though, if everyone that is pessimistic has depression. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4kaii4/eli5_are_there_gradual_forms_of_depression_or_is/ | {
"a_id": [
"d3dfwcj"
],
"score": [
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"text": [
"As someone who is very depressed, it's gradual. Never binary. You have good days, you have bad days."
]
} | []
| []
| [
[]
]
|
|
fa95vx | why is it that it's possible to shake a cup with a bunch of dice in it to the point that they can all stack on top of each other? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fa95vx/eli5_why_is_it_that_its_possible_to_shake_a_cup/ | {
"a_id": [
"fiwq7rw"
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"text": [
"It's not just being shaken randomly. If you'll note, the predominant motion is a circular swinging. What they're doing is forcing the dice to the edge of the cup and getting them to swirl around. If done right, that forces the dice to assume a vertical stack inside the cup. It takes practice of course, but it's no more magic than any physical trick like that."
]
} | []
| []
| [
[]
]
|
||
3eofhe | how come putin has the same power in russia now as a prime minister as he had as a president? | Why doesn't current president have the same political power that Putin had as a president? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3eofhe/eli5_how_come_putin_has_the_same_power_in_russia/ | {
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"text": [
"Vladimir Putin *is* the President of Russia. Has been since 2012. Before that he was Prime Minister. Before *that*, he was President. \n\nIt is fairly accepted that he was still running things when he was Prime Minister, though and that the president at the time (Dmitry Medvedev) was merely his puppet. ",
"Being prime minister was a dodge to avoid term limits. The acting president intentionally let Putin make the decisions.",
"Because he's only there because Putin put him there. If he wasn't willing to let Putin make the decisions, Putin would have chosen someone else."
]
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1lqbiu | What was the military organization, equipment, and tactics of Carthage like during the Punic Wars? | I've been playing Rome 2 as Carthage and was interested in seeing what the actual Carthaginian forces were and how they worked. I'm curious about the military organization, equipment, and tactics of Carthage during the Punic Wars, especially in comparison to Rome and other surrounding powers. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1lqbiu/what_was_the_military_organization_equipment_and/ | {
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"In large part, the Carthaginian armies during the first Punic War were largely composed of mercenary troops from a variety of different areas under the control of Carthage (think North Africa, Spain and southern Gaul). \n\nDuring this period, the command was generally along the lines of the Romans - upper class members who could afford the armour and weapons with ~~the King~~ senior general (Roman = consul) in overall command. ~~This changed in the 2nd and subsequent wars when a more professional command structure was instituted (ala Hannibal)~~\n\nIn the 2nd Punic War, the makeup of the forces lent more heavily on a formal African contingent made up primarily of heavy infantry spearman - think Greek Phalanx based and you won't be too far off the mark - with Phoenician/Spanish swordsman and then irregulars based around Gaulish troops.\n\nCavalry were where the Carthaginians had it over the Romans as their javelin equipped Nubians were considered the best in the world at the time.\n\nThe general tactics were for the Numidians to ride up to the Roman lines and conduct fast skirmishes to break up the Roman ranks. These were then followed up by the heavy cavalry (mainly Libyan/Phoenician) who drove into the Roman infantry. Into this hole was then marched the heavy spear equipped infantry supported by sword wielding heavy infantry and the lesser equipped lighter Gaulish irregulars.\n\nElephants also formed a basis for \"shock troops\" and would generally be used on the flanks and/or on the front with infantry in support.\n\nThere is a good book on Scribd that goes into much more detail on the make up of forces during the Punic Wars. You can find it [here](_URL_0_).",
"Follow up question on this topic: I read in [I think it was] \"Carthage Must be Destroyed\" that the elephants Hannibal used were a now extinct breed of Moroccan elephant, which was actually quite small (size of a camel). \n\nI had never heard of this and still skeptical. Does anyone know whether this is true or that if it was indeed the huge African elephants?"
]
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o7nee | what are you supposed to do when an emergency vehicle passes you on the opposite side of the road? | If you aren't interfering with them is it ok to not slow down? I'm guessing it's just judgment based on the situation but I'm wondering if there is a specific rule or anything. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/o7nee/eli5_what_are_you_supposed_to_do_when_an/ | {
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"If there is a physical obstruction in the median (for example trees, bushes, dirt etc.) then you do not need to do anything but if it is just yellow lines or there is a big enough opening for them to cross onto your side of the road then you should pull over until they pass.\n\nThis is so that if for example traffic is heavy on the other side of the road they can cross over to your side or if the street entrance they have to go into would normally be blocked on their side of the road to get where they need to go.",
"[Move over America](_URL_0_) has the state by state laws. You know, for when you turn 15 and start working toward your licence."
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9iywvj | what is a generator in electricity? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9iywvj/eli5_what_is_a_generator_in_electricity/ | {
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"It's like an *electron pump* that pushes electrons away from one end and toward the other end. This creates a *voltage* (electric pressure) which is then used to power the flow of electricity through wires and other things.",
"I majored in physics and it sounds like these answers are dancing around what is causing the current. \n\nFirst you need a wire. This supplies the electrons that will become a current. In order to make them move you need to have a moving magnetic field. A generator simply uses some fuel to turn a magnet. If the wire (electrons specifically inside the wire) is coiled and inside a continually changing magnetic field it creates an emf (or electromagnetic feild). And bam. Electricity.\n\nThese forces are always tethered. Moving charged partials will in turn create magnetic fields. Hope this helps."
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6jc1bw | why are media companies so obsessive about pirating movies or music online, when just a few years ago people would record movies off of tv or music from the radio and it wasn't a big deal? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6jc1bw/eli5_why_are_media_companies_so_obsessive_about/ | {
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"They were making a big deal about it then, that's why they would put in warnings and videos about piracy, but they had to crackdown harder on internet privacy because the ease of it caused piracy numbers to skyrocket creating a bigger problem",
"Back in the 70's and 80' a small portion of every cassette tape went to the music industry. I'm not sure about VHS."
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3d0ls1 | Were there any devout Christians among the Nazis who participated in the Holocaust? How did they come to terms with the things they had done? How did they justify their actions in front of the altar of God? | If possible, I'd like to hear about whether these Nazid repented (in a religious way) after the war. It's interesting to think that some Nazis were also supposedly followers of a religion that preaches love and peace. I don't understand. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/3d0ls1/were_there_any_devout_christians_among_the_nazis/ | {
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"Not sure if this would be considered devout. Josef Tizo was a Catholic priest and also one of the leaders of the Slovaks Peoples Party a Clerical-Fascist party that was installed in power during WW2. It was also founded by another Catholic priest Andrej Hlinka, for which their paramilitary, the Hlinka Guard was named.\n\nThe party ruled from 1939-1945, pretty much the duration of the war. And its record is not pretty. The party not only acquiesced to every single Nazi request, but participated enthusiastically. This included the \"Final Solution\", the party actively used the state to find and deport Slovakia's Jews to the Polish death and concentration camps in 1942. This was on top of variations of the Nuremburg Laws (The Jewish Code as known locally) that had been enacted in 1941. \n\nThe leadership of the Catholic church was supportive initially, an apostolic blessing from Pope Pius XII was given to President Tiso after his ascension. They were not so pleased as the antisemitic nature of the clerical-fascist regime took hold. In general, Tiso was supported by large numbers of ordinary Catholic priests and deplored by the bishops and the Vatican itself. Though there are lots of exceptions, such as Bishop Jan Vojtaššák, who thoroughly supported Tiso and the persecution of the Jews.\n\nWhile opposed by the Church, the Vatican made no effort to excommunicate or restrict Tiso (or his prime minister, also a Catholic priest). \n\nAfter the war, Tiso would be tracked down and arrested by the American occupying forces and handed over to a judicial tribunal in Czechoslovakia the Americans had organized. This was prior to the takeover by the Communists. Tiso was condemned to death and executed in 1947 for his crimes against Slovakia's citizens, including Jews. \n\nIn 1995, the Catholic Church did a good job of offending Jews when Pope John Paul II proposed beautifying previously mentioned Tiso supporter Bishop Jan Vojtaššák for his opposition to the Communist state. Despite that Jan Vojtaššák had not found a persecution of Jews he could not support.\n\nSome Sources:\nDr. Pavol Mest’an, Slovak historian, director of Museum of Jewish Culture of Bratislava\n\nThe Vatican, the Catholic Church, the Catholics and the Persecution of the Jews during World War II: The Case of Slovakia in Jews and non-Jews in Eastern Europe by Yeshajahu Jelinek, University of Minnesota, 1974 (at the time, he jumped back to Israel's Hebrew University after his stint in Minnesota)\n\nThere is another book specifically on Slovakian Jews was contributed to by Yeshajahu Jelinek, The Tragedy of the Jews of Slovakia: 1938-1945 Slovakia and the Final Solution of the Jewish Question, published in 2002 I have yet to read. "
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42iokp | many american football players have brain diseases in their old age because they have so many concussions during their career. why don't rugby players, who don't wear helmets, have this problem? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/42iokp/eli5_many_american_football_players_have_brain/ | {
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"Because American Football players wear helmets and protective armor, they regularly crash into each other way more violently than rugby players would, leading to the apparently paradoxical effect that football players' \"protection\" actually make the sport more dangerous. \n\nIn a similar case, the introduction of soft, cushy gloves in boxing has lead to significantly more deaths in boxing matches, since boxers were now able to hit their opponent's head with great force without breaking their own hands.",
"They do have the same problem. But the research was done on football players so that's what we're talking about. ",
"I used to wonder this as well until I started watching rugby. When they \"tackle\" each other to the ground it's more like an aggressive wrestle. ",
"I work in big time college football and \"rugby tackling\" is so hot right now. Pete Carroll of the Seahawks has been teaching this for as long as I can remember (here's a video if anyone is interested _URL_1_). \n\nLike others have state here the hard helmet and facemask give the player the illusion that they are protected. Vicis is a new company with a soft helmet that is trying to keep the helmet (and violence of the game that's so popular) and increase the safety of the player (here's their website with a fantastic promo if anyone is interested _URL_0_).",
"It's all about the tackling and how they are trained to tackle. Far less head injuries in rugby",
"I was curious if there had been any studies done on concussions in rugby. Here are some articles that actually compare football to rugby.\n\n_URL_3_\n\n_URL_1_\n\n_URL_0_\n\n_URL_2_\n\ntl;dr: concussions are very common in rugby, at a comparable rate to the NFL. Also, never race horses.\n\n*edit: missed \"rate\" in the last line",
"[Risk Compensation](_URL_0_) \n\nBasically people will take more risks if they feel safer, or less risk if they feel more vulnerable.",
"There are a few reasons, many of which are covered in length here, but also:\nTackling above the shoulder in rugby is a big no-no. This is great way to get sent off the field, while the other guy gets sent to the hospital.\n\nIt has been my experience that -apart from the usual vicious rivalries- rugby players have a sense of brotherhood and innate respect for anyone who is willing to lace up their boots and play. Yeah you want to knock that guy on his ass, but you also want to drink some beer with him after, and then play some more rugby with him. It is much less fun to do that if you or he are concussed. Sportsmanship exists in football, but it is a much more integral part of rugby.\n\nExcessive violence is generally highly celebrated in football, and discouraged in rugby. If you \"ring someone's bell\" in football you get a slap on the ass and a sticker on your helmet after the game. In Rugby you can get penalized or yellow/red carded.\nIt is also very likely that you put a bullseye on your own back. My former rugby team had a play known as \"Fuck that Guy\" if someone on the other team was punching, kicking or otherwise playing violently and not getting a stern talking to from the ref, we would, whenever the ref wasn't looking would pull hair, eye gouge, rake (stepping on him and then dragging your cleats across his body) or punch him, until he got the message or limped off the field.\n\n"
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"http://www.englandrugby.com/mm/Document/MyRugby/Headcase/01/30/54/78/Concussioninrugby_Neutral.pdf",
"http://www.brain-injury-law-center.com/latest-news/head-injuries-rugby-vs-football/"
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6f60dj | When history says "Alexander founded a new city," what is being described here? | For example, did he literally choose the location for a brand-new settlement? Or did he just take an existing settlement and decided to make it more important by leaving a bunch of soldiers/officials there? In either case, how many people did he leave behind? Did this affect the fighting capabilities of his army? Did the Greek settlers outnumber the locals, or vice versa?
Thank you for any responses | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/6f60dj/when_history_says_alexander_founded_a_new_city/ | {
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"Hi, not discouraging responses here, but fyi there was a fairly lengthy thread on this topic last week that would be worth catching up on - see here\n\n* [In ancient times I've heard that historical figures \"built cities\" like Alexander did at Bucephala in honor of his horse. How did a ruler in Greco times go about establishing a city? What did that at a minimum constitute?](_URL_3_) featuring /u/ikahjalmr\n\nAlso\n\n* [Who populated the cities founded by Alexander the Great?](_URL_1_) featuring /u/Daeres \n\n* [How did Alexander the great build alexandria?](_URL_0_) featuring /u/Docimus\n\nOf possible tangential interest\n\n* [How were cities founded by traveling armies in antiquity?](_URL_2_)\n\n* [There's a legend that Hercules himself founded my city (Cádiz, Spain) 3000 years ago. Can anyone direct me to that legend or tell me something about it?](_URL_4_)"
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"https://www.reddit.com/r/AskHistorians/comments/4665k4/how_did_alexander_the_great_build_alexandria/",
"https://www.reddit.com/r/AskHistorians/comments/1i7aqp/who_populated_the_cities_founded_by_alexander_the/",
"https://www.reddit.com/r/AskHistorians/comments/3bzn9c/how_were_cities_founded_by_traveling_armies_in/",
"https://www.reddit.com/r/AskHistorians/comments/6dfnei/in_ancient_times_ive_heard_that_historical/",
"https://www.reddit.com/r/AskHistorians/comments/3a47qs/theres_a_legend_that_hercules_himself_founded_my/"
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1gtbbl | Do we have any idea what the relationship between Sumer/Mesopotamia and Egypt was? | I'm talking anything.
* Wikipedia makes it sound like they overlapped in time, so I'm curious if there was any trade or idea exchange or contact or anything?
* Mesopotamia is often called the "cradle of civilization", so do we know anything about how it spread from there to Egypt, or were they completely different developments?
* Or did Egypt come first and "cradle of civilization" is a misnomer about Mesopotamia?
* War?
Or anything else, really. I'm just curious about these early human beginnings and how/if they were related.
Thanks in advance. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1gtbbl/do_we_have_any_idea_what_the_relationship_between/ | {
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"According to [this website](_URL_0_) \"There is no mention of the Egyptians in the Sumerian archives, or vice-versa, and there is no direct evidence that they had a noticeable influence on one another, except for their propensity to build giant pyramids and ziggurats. Although on a modern map they appear to be quite close, they seemed to have been completely unaware of each other’s existence. Back then, the world was a much larger place.\""
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4w3km1 | if i have an electrical circuit, run a current through it, and then suddenly interrupt the circuit, what happens to the electricity still within the circuit? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4w3km1/eli5_if_i_have_an_electrical_circuit_run_a/ | {
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"Imagine a channel of water. On one end you pump in water, on the other end you suck water away. Imagine that you suddenly stop doing both. The water briefly builds up due to leftover inertia and then it stops moving.\n\nSame thing in a circuit. The electrons are slowly moving through your circuit. If you interrupt it the electrons stop moving. Electricity is the movement of the electrons in one direction, not the electrons themselves.\n\nThe brief buildup also has an equivalent in electricity, inductance in electrical circuits is equivalent to inertia in water flows. So if you take a big coil (lots of inductance) and you suddenly interrupt a current flowing through it you get a pretty damn big spark. That's how spark plugs in your car work.",
"If you are talking about a simple circuit, the simple answer is nothing happens to it, it just stops flowing. \n\nElectricity is the flow of electrons. Voltage is how hard the electrons are being pushed. When you apply voltage to an electron it moves. This movement is what is referred to as electricity. When you interrupt the circuit it no longer has anywhere to go, so it stops moving. \n\nIt's like when you turn your water off at a sink, the water is still in the pipes, but now that you've closed the valve, the water has no where to go so it stops moving. ",
"Some great answers, but what I feel you have to realize is that the 'electricity' or electrons are present whether or not you're running a current. It's not like an empty channel; the electrons were present before the current and never changed appreciably. Some moved in at one end and some moved out at the other. That's all.",
"An electrical circuit has a property called inductance. While resistance is the property of a conductor that opposes current, inductance is the property of a conductor that opposes *changes* in current. Without going into much detail, it's caused by the magnetic field around the conductor created by the current going through it.\n\nThere's a good water analogy for this. Imagine a pump and loop of pipe with a large water turbine in it. The pump starts running and the water slowly starts flowing faster and faster as the big turbine with a lot of inertia starts spinning faster and faster. When you shut the pump off the turbine is still spinning and wants to keep spinning because of it's inertia. The spinning turbine now acts as a pump itself and forces the water through the loop. If there is a restriction to the flow, the pipe or pump may burst.\n\nIn the actual electrical circuit the inductance wants to keep the current going, and if the circuit is broken suddenly, it may even arc over the switch contacts. This is analogous to the turbine bursting the pipe.",
"In reality electricity is not quantifiable like this question appears to assume, there are also a lot of transient effects that can happen when you go from a completed circuit to an interrupted circuit. For the sake of answering this i will assume that we go from a completed circuit to a disconnected circuit at steady state.\n\nIf we think of electricity as energy (as in what your utility company charges you for) then electricity must be measured over a length of time. You don't have a volume of it like you would have a volume of water in a glass.\n\nWhat is generally used to quantify electricity is kWh (kilo Watt-hours) which is a measurement of power over a length of time. Power is itself defined as Voltage times Current.\n\nEnergy = V * I * t\n\nFrom the equation we can immediately see that when we interrupt the circuit and current goes to 0 we have 0 real energy. What is left is the electrical potential, or Voltage.\n\nThe voltage of the circuit will change on both sides at the disconnect on the circuit. While the circuit is connected the length of the circuit will have a voltage gradient where the measured voltage will vary along the entire length of the circuit from the source voltage all the way down to 0. Once the circuit has been interrupted, the positive side of the disconnect will rise up to the source voltage, while the negative side will drop down to 0. Essentially the voltage will be flat, across the length of the circuit, with the disconnected points acting as the change from source voltage, to no voltage.\n\nSo in short when you interrupt the circuit you go from a real energy being used to a potential energy that is available. The potential energy available ends up being whatever your source can provide. \n\n\n\n\n\n\n",
"There is a ton of misinformation here, but there is really no ELI5 way to accurately describe electricity. Electricity is not just the \"flow of electrons.\" In fact, electricity cannot adequately be described using any single definition. \n\nElectrons do move in a conductor, but they do not \"flow\" like water through a channel. In DC circuits, electrons move from negative to positive, albeit very slowly (inches per minute). In AC circuits, they just wiggle back and forth but don't actually flow at all. \n\n/u/GlamRockDave was correct in stating the water analogy is misleading, but he's gotten downvoted on every post for trying to point out the common misconceptions. I'm sure I'll be downvoted as well, but I can live with that. "
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1kbb68 | When did nations begin to regularly levy taxes? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1kbb68/when_did_nations_begin_to_regularly_levy_taxes/ | {
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"Can you winnow this question down more, whether geographically, temporally or both? It's quite broad, considering that taxation was introduced, disappeared, and reintroduced at varying times as well as varying regions throughout history.\n\nAre you talking about taxation in antiquity? Late medieval European feudal taxation? Or specifically state taxation of the early modern period? Taxation in coin, or taxation in kind? \n\nPlease be more specific. \n"
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bf94sd | What are those curvy distortions in the air above a hot stove? | askscience | https://www.reddit.com/r/askscience/comments/bf94sd/what_are_those_curvy_distortions_in_the_air_above/ | {
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"The index of refraction (how much the speed of light changes through a medium) of a gas depends on its temperature. What you are seeing is light going through regions whose temperature is changing (and possibly also a changing composition, e.g. leaky propane above a bbq). You can see it more clearly with [Schlieren imaging](_URL_0_)."
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3hjlns | what happens during an internet outage? | When broadband subscribers are left unable to connect to the internet, what is happening behind the scenes? How do ISPs deal with an outage and what is actually happening to infrastructure? How can a storm affect the possibility of an outage? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3hjlns/eli5what_happens_during_an_internet_outage/ | {
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"There can be a million reasons ... The chain from you to the data center is: PC -- > LAN -- > Router/Modem -- > Landline/cable/fibre to some more central place (plus converters) -- > Another Router/Modem -- > fatter line to data center -- > [more hardware] -- > interconnection with other ISPs -- > repeat until you reach your destination page.\n\nliterally anything in that chain can break or in the case of routers be misconfigured.",
"There'll be people working out where the problem lies, and how to fix it.\n\nThere's a lot of equipment involved in connecting you to the internet. The more important connections and devices in the chain are \"redundant\", where there will be a backup that can take over fully if the primary system fails (hopefully that has been tested to ensure that it does take over). Others are not redundant - if they fail, they will cause an outage.\n\nAn outage could be caused by lots of things. It could be as simple as a misconfiguration somewhere, to a building being on fire or flooded or has lost power. There's even been outages caused because of burglary - someone broke into a facility and literally stole the network equipment\n\nAny ISP worth their salt will have tons of monitoring on everything they can monitor, so as soon as something fails, they know what appears to have failed and can try to fix it. Hopefully it's something that has a backup, so it can be fixed or replaced calmly, rather than causing a massive outage that needs immediate attention and needs to be fixed yesterday\n\nStorms could take out equipment (for cable or DSL there may be equipment in your neighbourhood that won't like a lightning strike, or if they lose power), or maybe they damage the cables themselves"
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2537bd | Why do scientists currently refer to Dark Matter as matter? Isn't it possible that the evidence for Dark Matter may actually be an incomplete understanding of gravity or other forces? | I've read that Dark Matter, if it is a substance, does not react with anything except gravity. There has never been any direct evidence that any type of matter or particle is involved at all. That being the case, why do scientists think that there is a substance involved when there appears to be no evidence for it being a substance? | askscience | http://www.reddit.com/r/askscience/comments/2537bd/why_do_scientists_currently_refer_to_dark_matter/ | {
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"I've had this same question. Observations of galactic interactions, however, point strongly to a cloud of invisible matter that accompanies galaxies. This is famously evident in the bullet cluster, where the mass distribution just isn't right, until one factors in dark matter.\n\n_URL_0_\n\n",
" > Isn't it possible that the evidence for Dark Matter may actually be an incomplete understanding of gravity or other forces?\n\nYes, it's possible. Actually several scientists have thought of this and proposed alternate theories aimed to refine gravitation. They are [MOND](_URL_0_) and it's relativistic version, [TeVeS](_URL_2_).\n\nThey are good at explaining the galaxy rotation problem. However, MOND cannot explain [gravitational lensing](_URL_1_). TeVes can, but it's not completely consistent with the observations. Particularly, the behavior of the Bullet Cluster pointed out by thiosk is *not compatible with any current modified gravity theories* - quoted from [TeVeS](_URL_2_).\n\nSo far Dark Matter is the theory that best explains the observations.\n\nninja edit: accuracy",
"I'm going to reuse [an old comment](_URL_2_) for this:\n\n----\nSo we haven't ruled out alternate gravity theories, but the majority of astronomers are definitely in the WIMP dark matter camp. There are alternate gravity people, but it hasn't really caught on at all. But yet, in the general public people seem to think of dark matter as some sort of weird phlogiston theory, and that it seems much \"simpler\" to \"just change gravity\".\n\nSo I'll try to defend why dark matter isn't as weird as it seems:\n\n1. We already know that there are particles that interact only through the weak nuclear force and gravity: neutrinos. We have built neutrino detectors and found them. We're just looking for a fatter neutrino, not something entirely different to anything we've ever seen before.\n\n2. The Bullet Cluster can't be explained by alternate gravity - it really shows that the gravity is not where the visible matter is.\n\n3. It's actually quite elegant physically, because we have all the physics for particles worked out. We can set up a simulation with a bunch of dark matter and see if it falls into galaxy-sized clumps etc. This means it's a very testable theory, because it's not as flexible as changing gravity. We have some unknowns (like the mass of the particle), but we aren't changing the basic laws of physics, so we can run simulations and make predictions for observations, and hence either confirm or rule-out dark matter. For example, dark matter should be its own anti-particle, so with a good enough instrument we should be able to observe the gamma-rays it produces\n\n4. Some fairly sensible extensions of the \"standard model of particle physics\" naturally produce a particle with properties very similar to what a dark matter particle should be. Although there's no proof that any of these models are correct yet, so this point is not super solid.\n\nAlthough it's worth pointing out that we really do need to actually find the particle before this is in the 100% confirmed category, it's definitely the favoured option.\n\nNext: why is changing gravity weirder than it seems?\n\n1. Einstein changed gravity by making a very small number of very strong assumptions, and all of general relativity naturally flowed from that. GR is basically the simplest possible solution that satisfies these basic assumptions. But if you're making GR more complex, you can change it in any direction you like. You can make it fit pretty much any data you want. You aren't bound by the laws of physics any more, because you're changing these laws. So if anything contradicts your theory, it's much easier to adjust your theory to make it fit. So it's much harder to prove or disprove the theory, and that makes it unsatisfying.\n\n2. The most popular model, Modified Newtonian Dynamics (MOND) doesn't even change GR properly. It's more or less just an ad-hoc modification to basic Newtonian gravity to make it fit the data. The fundamental physics isn't justified at all, it's literally just changing the equations to fit the data.\n\nSo, to put it a bit harsher than it probably deserves, we have a choice between a minor adjustment (adding a new particle similar to other particles we have observed) that is inflexible enough and specific enough to be properly tested, and a major adjustment (changing the fundamental laws of general relativity) that is too flexible and unspecific for us to design really good tests to confirm or disprove it.\n\nThis is all my perspective as an astrophysicist. Someone who does particle physics or who works directly on general relativity may have a different opinion.\n\n----\n\n[hikaruzero](_URL_0_) then [replied](_URL_1_) to explain the particle physics a bit more:\n\n > There is a much simpler candidate for a dark matter particle that does not require invoking supersymmetry: a sterile neutrino. This is actually currently the most favored candidate, more favored than a neutralino or other supersymmetric particle. And indeed, evidence for supersymmetry has not been found in most of the places we expected to find it if it exists, so it must be a badly broken symmetry if it does exist at all (and that raises the question of why it is so badly broken, which is basically just fobbing off the heirarchy problem and not really solving it).\n\n > The main reason it is favoured is because it \"kills three birds with two stones,\" so-to-speak. In the current Standard Model, all of the known fermions have both left-handed and right-handed versions *except* for neutrinos -- we have only observed left-handed neutrinos. Additionally, only left-handed particles interact via the weak interaction, so if a right-handed neutrino did exist, it would be expected that it would *only* interact gravitationally, and not through any of the other three fundamental forces. Furthermore, the known left-handed neutrinos have an extraordinarily small but apparently nonzero mass, and there is the question of why their mass is so small.\n\n > There is a proposed mechanism called the [see-saw mechanism](_URL_3_) by which the mass of the left-handed neutrino can be driven down, but only if there is a corresponding increase in mass of a right-handed neutrino.\n\n > Introducing a right-handed sterile neutrino (stone 1) with a Majorana mass tied to a see-saw mechanism (stone 2) would solve the problem of why right-handed neutrinos have never been observed (bird 1), why the known left-handed neutrinos have such a small mass (bird 2), and also provides an ideal candidate for a very massive dark matter particle (bird 3).\n\n > Hope that helps!\n\n----\n\nI hope that's thorough enough for you :P"
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"http://www.reddit.com/user/hikaruzero",
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"http://www.reddit.com/r/askscience/comments/1q1cy4/do_you_favour_the_dark_matter_hypothesis_or_do/",
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3snuyq | What is an inertial frame of reference? | I am attempting to better understand Newtons laws of motion and currently stuck on the first law.
I've watched videos and read several textbooks but cannot find a precise definition that I can understand. | askscience | https://www.reddit.com/r/askscience/comments/3snuyq/what_is_an_inertial_frame_of_reference/ | {
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"It's a reference frame that's not accelerating. If you're just floating in space, you're in an inertial frame of reference. If you're on an accelerating spaceship, you're not, so you feel like there's something pulling you towards the engines when it's really just the engines accelerating towards you."
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740tkn | Looking at maps of Yugoslavia, its clear that large parts of Serbia, Croatia and Bosnia had ethnic majorities from one of the other nations. Did this cause problems before the 90's? Were there any attempts to change the internal borders? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/740tkn/looking_at_maps_of_yugoslavia_its_clear_that/ | {
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"The only real evidence I can find of any internal attempts to change borders prior to the late 80s/ early 90s was the Nazi and Fascist Italy attempting to \"persuade\" Croatia to become independent, to push for more autonomy so to speak. \nWhen Yugoslavia as a whole was invaded by Axis powers in 1941, Croatia was given independence from Yugoslavia by the Nazis, who then encouraged the Croatians to participate in the killing of Serbs within its borders (these killings seem to be more motivated by religious rivalries as opposed to nationalist or ethnic motives). \nIt was throughout this war that the Chetniks (Royalists determined to see the re-establishment of a monarchy) and the Partisans (communists) fought for control of Yugoslavia from the Axis powers (led by Nazi Germany). During this war, Josip Broz Tito distinguished himself when he led the Partisans to victory over both the Axis powers and the Chetniks. He had a dedicated following, dedicated enough that when the war came to an end, it was decided that the exiled monarch (King Peter II, the last King of Yugoslavia) would stay in exile. \nTito also received aid from the Soviets during this war, and the Soviets also helped him set up the Socialist Federal Republic of Yugoslavia in 1945. I'm harping on about Tito here because of the defining role he played in keeping Yugoslavia together during his reign as President. \nTito modeled his secret police on the Soviet KGB, they acted in a manner similar to the KGB, often extrajudicially and almost always omnipresent. Tito used his secret police to crack down on any feelings of nationalism, purging any and all growth of nationalism. The suppression of nationalistic feelings and an odd mix of deference and repression is what held Yugoslavia together during Tito's reign.\nTito allowed all ethnic groups to speak their own language. Eg; Croatians could speak Croatian and Serbians could speak Serbian and so on. However, in relation to Albanians, Tito took an incredibly harsh stance, arresting and imprisoning many Albanians for expressing their ethnic identity. According to Matas, almost half of the political prisoners in Yugoslavia were Albanians. This is significant because Matas also asserts that Yugoslavia had more political prisoners outside the USSR than the rest of Europe combined.\n\nI may have gone on a bit long about the role of Tito but that's because he was instrumental in keeping Yugoslavia together. When he died in 1980, the Presidency became decentralised and the country was held together by the ideological force of Communism. It was when communism collapsed in 1989 (with the Fall of the Berlin Wall etc.) that Yugoslavia lost its unifying factor and ethnic tensions began to rise.\n\nEdit: In my studies on this, I haven't found any evidence of attempts to change internal borders during Tito's rule\n\nResources:\nMatas, David (1994). No More: The Battle Against Human Rights Violations. ISBN 1-55002-221-0.\nFinlan, Alastair (2004). The Collapse of Yugoslavia 1991–1999. New York, USA: Osprey Publishing. ISBN 978-1-4728-1027-4.\nCorbel, Josef (1951). Tito's Communism. Denver, Colorado: The University of Denver Press."
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1ipyqt | Tesseract 4th dimension | Every time I see a visual model of a tesseract it looks like a cube inside another cube, attached by poles that extend from what looks like the centre of both cubes.
My question is, why is the 4th axis directed from the centre outward? Is this an arbitrary choice to create a 4D model in 3-space, or does the mathematical model describe the 4th spatial dimension that way?
Edit: My brain is melting. Thanks for all the contributions. I'm going to settle with the thought that it's 8 3-cubes surrounding a 4-space. Since a line is 2 0-spaces surrounding a 1-space of infinite 0-spaces; a square is 4 1-spaces surrounding a 2-space of infinite 1-spaces; a cube is 6 2-spaces surrounding a 3-space of infinite 2-spaces... so, *a tesseract should be 8 3-spaces surrounding a 4-space of infinite 3-spaces.* That's how I'll choose to make sense of it all, qualitatively. Many thanks for the contributions. | askscience | http://www.reddit.com/r/askscience/comments/1ipyqt/tesseract_4th_dimension/ | {
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"The square doesn't have to be within the other cube. When you see a tesseract drawn... What you're looking at is a 2 dimensional representation of a 3 dimensional representation of a 4 dimensional shape. If you were to build one out of matchsticks and view it front on at the correct angle, you'd start to get the illusion of two cubes occupying the same space (that's the reason for one cube being smaller for fake perspective).\n\nBut as I said it doesn't have to be inside. If you draw a square, and draw a smaller square within it, then connect the corners... You end up with a 2d representation of a cube. At the same time... The second smaller square does not have to be within the bounds of the first square... It can be offset for a different perspective.",
"What you're seeing can be considered the tesseract's 3D shadow. I always enjoyed Sagan's talk about [Flatland](_URL_0_) to help describe higher dimension ideas. Though this doesn't really answer your particular question.",
"I recommend taking a look at _URL_0_\nTo get a good understanding of how visual metaphors can help us imagine other dimensions. It's not accurate, but it is useful to understand how to imagine forms outside of our perception ( the best language of course being math, but visual language can be helpful too)\n\nThat being said, every dimension increase can be though of a perpendicular bisector to each dimension.\n\nSo :\n\n0.. Point \n1. Line - perpendicularly bisects a point\n2. X-y- perpendicularly bisects a line\n3. X-y-z - you have to have a z line now , on paper the only way to perpendicularly bisect an x-y axis would be to have a line coming out of the page.\n\nHere's where things get weird, instead we often use a diagonal line consistent with our understanding of 3 point perspective to visualize depth. But as mentioned earlier, this is a 2d representation of a 3d space. We can relate because perspective illusions are now common place but honestly a cube without imagination drawn on piece of paper looks weird!\n\n4. X-y-z-w Perpendicular bisector to all three lines- this is hard, we already used a visual illusion to simulate 3d, so merely choosing another diagonal line is going to fail, we don't have a class of visual illusion to use as a simulation. One artistic representation is of course the tesseract. ;)\n\nJust remember, \"the map is not the territory\" , you're looking at one way to imagine 4 dimensions in 2! It's a clever and beautiful image, but it's not accurate- so don't try to create a mental model of \"this is how 4 dimensions look\" because your brain doesn't process 4 dimensions that way, it's processes 3 dimensions over a time period.\n\nHope this helps someone\n\n\n",
"If a 3d cube can be made with 6 2d squares, from how many 3d cubes is a 4d tesseract made?",
"the important thing is how many borders are connected with how many corners and faces, which results in a border per corner ratio...",
"Shouldn't the tesseract demonstrate the movement of time? I thought time was the 4th dimension...? (Yes this question is serious, I know nothing about this stuff but it seems fascinating.)",
"A line is a point extruded in a direction perpendicular to itself. Whichever direction you choose has now created a single spatial dimension. It has 'left' and 'right,' but no up or down, forward or back. You now have a 1 dimensional line.\n\nA square is a line extruded in a direction perpendicular to all of its points. That direction is either up and down, or forward and back. It doesn't matter which, but it can't be both. Say it was backwards. You now have a 2 dimensional planar space. \n\nA cube is a square extruded in a direction perpendicular to all of its lines. We generally consider it to be the Z axis, which is up and down. You now have a 3 dimensional volumetric space. \n\nA tesseract is a cube extruded in a direction perpendicular to all of its cubes. Now that doesn't make sense because we cannot conceive of a 4th spatial dimension. We try to demonstrate this by drawing it in a similar manner as we do a cube on a 2D space. Note that when you draw a cube on a 2D page, not all of the lines form 90 degree angles. But in a cube in 3D space they do. So, when we draw a tesseract not all of the lines form 90 degree angles, but in 4D space they would.\n\n[This](_URL_1_) shows an unfolded tesseract just as [this](_URL_0_) shows an unfolded cube. To form the tesseract you'd fold all 8 cubes into a fourth dimensional space. From a 3D point of view all you would see is a cube, just as when you look at a cube from a 2D point of view all you see is a square. Same all the way down to a point.\n\nDoes this make more sense?",
"I think it makes a lot more sense once you see it rotating so you can view the projection from different angles.\n\n_URL_0_\n\nIf you look carefully you can see how it is 8 cubes mutually connected by their faces. \nA cube similarly is 6 squares mutually connected by their edges (lines). \nA square is 4 lines connected by their end points. \nA line is a connection between 2 points.\n\nI always liked how it goes 2 4 6 8",
"I read about a great way to help you think about higher dimensions.\n\nImagine putting your hand into a pool, fingers first.\n\n2d creatures, who would love on the 2d film of the water, would see a point slowly get larger until another appears then morphs together and continues to grow and combine with others until you are in up to your wrist.\n\nNow think of a higher dimension creature doing this to us. We would see a 3d blob appear out of nowhere, grow and morph into another blob and strangely warp and move around.",
"Think of a zero dimensional object. That's a point. The point does not occupy any space at all. This point can exist anywhere, but it doesn't matter how it is oriented. \n\nIf you take that point, and duplicate it, and move it relative to the first point, you can draw a line between the two. Now, this line can exist anywhere, even in 2 dimensions, but the object itself is only 1 dimension. An example is of a line on a plane - you can create a set of axes and draw a line from 0, 0 to 5, 5 and that line would extend in the X and Y directions, but take the axes away and it is still only represented by a single dimension.\n\nNow, do the same thing again - take the line, and duplicate it, and create lines between each of the vertices that were duplicated. This creates a parallelogram, as long as the 2nd set of vertices have the same transformation relative to each other. This shape has two dimensions, because even if you took away the axes you can see that it requires two variables to describe each vertex position.\n\nDo the same thing again, and duplicate all the vertices. You now have 8 vertices, and as long as the 2nd set of vertices moved normal to the first set in the same distance as they are long, you have a cube. This is a three-dimensional object, because each vertex requires three variables to describe. See where this is going?\n\nNow, do the same thing again. You have 16 vertices - and nowhere to put them physically. Since the universe ostensibly exists in three spatial dimensions, we would need a 4th to graphically represent the additional vertices. Since we can't, we have to project their locations into 3d. This is basically just a trick - you aren't seeing the whole object, just the slice that happened to be projected for you. But that doesn't mean that the object doesn't exist, mathematically. \n\nNow, for hyperstuff. Anytime someone says \"hyper\", like in \"hypercube\", or \"hyperplane\", or \"hypersurface\" they are referring to objects that exist in three dimensions but are extended to many dimensions. Many being variable, so something like \"n\" dimensions. This is important because we can keep describing things in similar manners, because the math all checks out. \n\nFor example, in 3 dimensions if we have 2 variables X and Y, we can create a dependent variable Z such that Z = f(x, y). This gives us a surface. A surface that is flat, is called a plane. Now, if we take the same logic and say W = f(x, y, z) - this creates a hypersurface. It can represent density, or the amount of stuff crammed per unit space in 3 dimensions, so it's still got a physical meaning. But if this surface is 'flat', mathematically, we can call it a hyperplane (Rather than a hypersurface). We need to go deeper! \n\nFinally, let's do H = f(a, b, c, d) - this requires 5 variables to describe every point. You can keep doing this, ad infinitum. Any time you add another independent variable, you are creating a higher-dimensional object. One application of these is in machine learning. For example, it is easy to see that 2 points on the XY plane are linearly separable - because you can separate them with a line. But the same math that you use to determine this can be applied in N dimensions. Another example is training - if you have a neural network with N inputs, it becomes a linear function of f(a, b, c, d, ...n) where a, b, c, d, up to n are its inputs. If we put the values in with the weights we have selected, we can subtract the 'expected' value to get the 'error' value. This creates a hypersurface that we call the error surface. We can use calculus in 3 dimensions to find the gradient of such a surface intuitively - this is important because the gradient is the direction of steepest ascent, so the negative of the gradient is the direction of steepest descent, and since we are talking about an error hypersurface, we can use gradient descent to pretty much ski down the error surface to some minimum point. This can all be extended to N dimensions (which is a good thing, too, because a lot of neural networks have millions and millions of neurons!).\n\nOh, tesseracts. Yeah, these are just points extended into N dimensions, where N = 4. ",
"Anyone ever read \"A wrinkle in time\"? I read that book in 7th grade and i still remember how the book talked about tesseracting through the fourth demension aka travelling from point a to point b by cutting the distance in half by a fold. For example if an ant had to cross the newspaper what would be the easiest way? take one end and the other and put them next to each other (close the paper) and the ant steps to the other side. ",
"My geometry teacher put it this way about a depiction of a hypercube:\n\n\"It's a 2-dimensional drawing of a 3-dimensional model of a 4-dimensional cube.\"",
"5 year old here. I think the most confusing part about the depiction of a 4th dimensional object is that it appears like a 3 dimensional object that is moving. Does this depiction indicate that the movement is the 4th dimension? What is the purpose for depicting a 4th dimensional object? What about this depiction indicates whether or not it is actually 4th dimensional?",
"[Here is a picture of a cube.](_URL_0_)\n\nThe small square in the middle is the far away face, it's just smaller looking because it's farther away. But if you didn't know it was a cube, and could only think in two dimensions, you would say \"that's just a small square inside of a large square, does this mean that the third dimension points outward?\" No, the third dimension does not point outward, it's just a way of depicting that the other face is farther away. ",
"This might help visualize a 4th dimension:\n\nLet's say that you have a cube in orthographic perspective. We imagine the x, y and z directions on that cube. If you look into the end of that cube (so that z is currently toward and away from us, y is up/down, and x is side to side), and pretend that there is a fleck of dirt in that cube, you could easily tell where that fleck is on the x and y axes. You cannot, however tell where it is on the z axis so easily. It is only when you turn the cube that you can infer more information about the placement on the z axis.\n\nTo apply this to a 4th dimension, you cannot tell where a particular particle is in the 4th dimension with our 3D frame of reference. two dirt specks may seem very close to each other in 3D space, and two others may seem farther apart, but the first two may be farther apart than the second two, when you take the 4th dimension into account.\n\nLook at [this](_URL_0_) link if you want my more speculative approach.\n\nEdit: forgot the link.",
"Around halfway of the video, there's a very interesting representation of a 4D object, it might help you a little bit:\n\n_URL_0_",
"As far as visualizing 4D goes we are limited because of our confinement to three dimensions but we can still make analogies based on how we do see.\n\nAs three dimensional beings our vision is made up of 2 dimensional vertical slices, the only way we intuit that we are in 3 dimensions is by things like shadows and perspective and the way those 2 dimensional slices change as we move in one of the six directions that we can move in.\n\nSo it stands to reason that a 4D being would see in 3 dimensional slices, meaning that if a four dimensional being were watching you right now, he or she would be able to see every side of you at the same time. \n\nWe as 3 dimensional beings have to turn around to see behind us or walk around an object to see what the back of it looks like, a 4D being would have no such limitation. They could see your face, your back, the top of your head, and the soles of your feet all at once. In addition to that they could see inside of you without having to cut you open.",
"This is less scientific than it probably should be, but I had a professor who always explained those images of tesseracts as being like representations of three-dimentional shadows. And the animated gif. on [this](_URL_0_) page is like looking at the shadow of an object that is rotating."
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bzamp4 | why do instruments sound different if sound is just vibrating air? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bzamp4/eli5why_do_instruments_sound_different_if_sound/ | {
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"It all has to do with what they call timbre.\n\nDifferent instruments may be capable of playing the same note or pitch, but they all do it differently. Not only is the pitch (or frequency of the note) being sounded, but also other frequencies get sounded, too. These might be overtones, or multiples of the intended frequency, or other non-multiple frequencies. Which additional frequencies are sounded, and their relative strengths compared to the pitch frequency, color the overall sound. That is the instrument’s timbre.\n\nThe timbre is a function of many properties of the instrument. An instrument that creates sound through cavity resonance, like a clarinet, will excite different frequencies than an instrument that creates sound through vibrating a string, like an electric guitar. And then different models of the same instrument can excite different frequencies through the use of different materials, or different playing skills, or slight changes in design, etc.\n\nHope this helps!"
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6m0ytn | there are people who claim that drinking beer gives them a "happy-go-lucky" drunk, but drinking whiskey or liquor makes them a "mean" drunk. what could cause this? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6m0ytn/eli5_there_are_people_who_claim_that_drinking/ | {
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"It's mostly due to accelerated drunkenness. 1 shot of 80 proof liquor is roughly equivalent to 1 beer. So taking a shot is like drinking a whole beer in a matter of seconds. Even if you sip liquor, most people will end up drinking it faster if you are out with the boyz. So people that claim that a certain liquor makes them act a certain way probably just got drunk faster than they expected. ",
"The active ingredient in all of these beverages is alcohol, specifically ethanol, also known as ethyl alcohol. The only real difference between getting drunk via beer vs. getting drunk via \"spirits\" (whiskey, and other liquors, are also known as spirits) is that the alcohol in spirits is more concentrated, so the beverage is smaller, so one can consume it faster, then consume one beverage after another, and therefore get intoxicated faster. But people *expect* different beverages to have different effects, so they behave accordingly. It's a myth. Alcohol is alcohol."
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5u88pe | If the population of rome was so large in its early history, why is there so little written down? | With regards to contemporary writings of the early republic, mainly. | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/5u88pe/if_the_population_of_rome_was_so_large_in_its/ | {
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"Why are you equating size of settlement with presence of surviving written literature? The two are in no way correlated. We have a plethora of sources from democratic Athens, including tragedy, comedy, history, and philosophy, and that city was absolutely tiny compared to Rome as far as population. We have only scraps from her contemporary equals in population--Corinth, Miletus, Syracuse, for instance.\n\nMeanwhile, Carthage was one of the biggest cities in the Mediterranean in the Hellenistic period and barely a word of written literature survives from there. Throw in Gadir (Cadiz) as well. Or Tyre, or Sidon. The list of what survives today has more to do with subject matter, tastes, and the accident of preservation.\n\nThere were plenty of texts being written in the early Roman period. Livy drew upon the now-lost works of Quintius Fabius Pictor (3rd century) and Lucius Calpurnius Piso Frugi. Ennius and Naevius both wrote epic poems on Roman subjects, only fragments of which survive. Plautus and Terrence are well-preserved examples of early Roman comedy, but they were just two of many poets who were producing for the stage at the time."
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} | []
| []
| [
[]
]
|
|
2s9bxp | why isn't the data on a black box saved 'in the cloud'? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2s9bxp/eli5_why_isnt_the_data_on_a_black_box_saved_in/ | {
"a_id": [
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"text": [
"Some of the newer devices can upload data, but it's a recent development that hasn't yet spread to every airline in every territory.\n\nIt's a lot of data to push, if you don't have a good connection. Many planes just don't have that sort of bandwidth.",
"No doubt it will be one day.\n\nYou'd probably need a dedicated satellite constellation to do it though. Very high cost that no one airline would ever front.",
"Because all you care about is the last 5 minutes and that's not going to upload during a crash."
]
} | []
| []
| [
[],
[],
[]
]
|
||
4a183y | if there are over 7 billion people in the world & only a limited number of features on the face (eyes, nose, chin, etc.)that can determine how a person looks, why is it that almost everyone looks different? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4a183y/eli5if_there_are_over_7_billion_people_in_the/ | {
"a_id": [
"d0wjxrn",
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"score": [
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"text": [
"There may be a limited number of features on human face, but there is a near infinite number of tiny changes you can make to them. \n\nSubtle changes in size, shape, and position of each of the individual features all add up to give everyone their own unique look.\n\nRecognizing faces is immensely important for non-verbal human communication, as well as being able to identify friends and family, and therefore the human brain evolved to be very, very good at facial recognition. ",
"There's probably like a billion different 'face combinations' (?), people with wide eyes, different shape face, nose, ears, mouth, eyebrows, different colour eyes, skin tone, hair. Im assuming if two people looked exactly the same, changing just their eye colour/hair or position of their mouth will probably make them look 'completely' different",
"Because you don't know seven billion people. In fact, you probably don't even know a million either, maybe a few thousands. So, you know a few thousands different faces, that's not a lot. If we had ten kinds of nose, ten kinds of mouth and ten different hairstyles that's 1000 faces already. Surely there's more kinds of variation. \nNow, if you actually knew a billion people, I'm sure you'd find some almost identical, beyond human capacity to distinguish. "
]
} | []
| []
| [
[],
[],
[]
]
|
||
1uixqj | when big movie producers send out movies to be reviewed by critics, shouldn't it be easy to catch who uploaded the dvdscr? | I hate to be a paranoid parrot, but what's stopping them from sending slightly different copies to different reviewers? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1uixqj/eli5_when_big_movie_producers_send_out_movies_to/ | {
"a_id": [
"ceil6j1"
],
"score": [
2
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"text": [
"It's a decent idea.\n\nAmazon tried to do something simillar for their e-book sale, they thought of placing 1-2 random spelling mistakes in each one, to see who uploaded something at a torrent tracker. But eventually they abandoned the plan. \n\nI'm not answering your question though :( "
]
} | []
| []
| [
[]
]
|
|
3qtynz | why are fruits that can be grown on the east coast so much more expensive to purchase than produce in california? | Some fruits like avocados make sense why it's cheaper in California but what about fruits like apples that can be grown closeby, thus not requiring much middle men for transportation and stuff which would increase the price | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3qtynz/eli5_why_are_fruits_that_can_be_grown_on_the_east/ | {
"a_id": [
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"text": [
"Transport is basically cheap. You might add a nickel a pound to transport a truckload across the country.\n\nTransporting by ship might be a nickel a ton per thousand miles.",
"/u/friend1949 explained why the shipping costs don't add significantly to the price, but that doesn't explain why the east coast produce is *more* expensive.\n\nPart of the answer is that the farms on the east coast are smaller, and don't have the economies of scale. But also locally grown produce is *perceived* as being better, thus allowing stores to charge more. It *is* better in many cases, but the perception is what's important and that applies across the board. Two well known examples of being better are fresh picked strawberries and tomatoes. (I think it was Garrison Keillor who described the pink, flavorless, mass-produced tomatoes as \"strip mined.\")\n\nApples, which you mentioned, are more interesting because they have names attached to their varieties, some of which are well-known trademarks, valuable as such. Most of the Oregon apples that I see on the east coast are Red Delicious - consistent, predictable, with a long shelf life, and a slightly sweet but bland flavor. Kids are very happy with them, but all it took was one trip to a Pennsylvania apple orchard during apple season to show me how boring they are.\n\nCompare that to Honeycrisp, a more recent variety that's both patented and trademarked by the University of Minnesota. (According to Wikipedia, the patent has expired in the US, and the trademark may be at risk.) It's usually sweeter than the better known varieties, has a bit more flavor, and decent shelf life. For whatever reason, their marketing has been successful and it commands a premium (often a dollar per pound more in the stores I frequent compared to other north east varieties). \n\nI also tried some Sweet Tango apples this year. This is a newer variety, also from U. Minn, and descended from the Honeycrisp. But, in spite of having much smaller supplies, it was cheaper than the Honeycrisp. Why? Because it's not as well known. Maybe someday it will be. ",
"Supply and demand. California farming operations are on an industrialized scale, and some fruits and vegetables are produced in multiple growing seasons a year. Fruits and vegetables produced in California are grown for the whole country, while a lot of east coast farms are geared towards local distribution, thus California markets are saturated with extra product year around, decreasing their value in local markets."
]
} | []
| []
| [
[],
[],
[]
]
|
|
5wo9y2 | why can't you compress a rar file with rar or zip? | Why can't you compress a RAR file, | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5wo9y2/eli5_why_cant_you_compress_a_rar_file_with_rar_or/ | {
"a_id": [
"debkofi",
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"score": [
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"text": [
"Compression is a technique for finding patterns in a file and writing it in a way that takes more space. For example instead of writing \"aaaaaaaa\" you may write 8*\"a\" which is much shorter. Or instead of writing \"abcdefgh\" you may write \"a\"-\"h\". However if you have already compressed a file and written it in the shortest way you can think of then another compression program will not have much luck trying to compress it further.\n\nIf you think of your file as a sponge. It consists of a sponge material and a lot of air. This is practical for cleaning but not very practical for transport. So you put in though a vacuum sealing machine to suck all the air out and put on a plastic seal to keep all the air out. Now the sponge is much smaller. But you read of another way to do it by using a vice. However when you put the already compressed sponge in the vice you can not get it much smaller. This is like trying to compress an already compressed file.",
"Software developer here,\n\nCompression works by reducing repetition. So if you're compressing \"aaaaaaabbbb\", it would look something like \"7a4b\", for example. There's not much else to reduce there. This is, of course, a simplistic example of compression. More sophisticated algorithms will perform a series of matrix transforms (arrange the data into rows and columns, then start rotating rows and columns like a rubix cube, or change the values in a mathematical way) in order to align the data into bigger sets of repeating sequences, and then reduce that similar to my example above. The output is the transformed and reduced data, and a matrix to transform the data back to it's original form. But in the end, there's just nothing more to reduce, and you end up with a larger file because you have to store the meta-data for the encompassing compression format."
]
} | []
| []
| [
[],
[]
]
|
|
mnehc | Considering the universe is constantly expanding, what would happen if you suddenly stopped in place? | Considering the constant expansion of the universe, the movement of the sun around the galactic core, and the revolution of the earth around the sun, what would happen if you suddenly stopped in place? How far would you end up in empty space within the first second of stopping? or would you end up as a pancake on the earths surface? And would you experience the passage of time any differently? | askscience | http://www.reddit.com/r/askscience/comments/mnehc/considering_the_universe_is_constantly_expanding/ | {
"a_id": [
"c32b691",
"c32b691"
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"score": [
2,
2
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"text": [
"Weird as it might sound, the expansion of the Universe doesn't actually mean that you're moving at all. It means that the distance we measure between two fixed points will grow with time. It's a statement about how we measure distances - or in other words, the geometry of the Universe - rather than what the stuff in the Universe is doing. So there's no point asking what would happen if you stopped in place, because to a very good approximation (ignoring our motion around the Sun, within the galaxy, etc., which are negligible on cosmic scales), you're stopped already!",
"Weird as it might sound, the expansion of the Universe doesn't actually mean that you're moving at all. It means that the distance we measure between two fixed points will grow with time. It's a statement about how we measure distances - or in other words, the geometry of the Universe - rather than what the stuff in the Universe is doing. So there's no point asking what would happen if you stopped in place, because to a very good approximation (ignoring our motion around the Sun, within the galaxy, etc., which are negligible on cosmic scales), you're stopped already!"
]
} | []
| []
| [
[],
[]
]
|
|
5xt81u | Why were so many Nazi war criminals released very early into their prison sentences? | [here](_URL_0_) is a list of them
excerpts like the following are on almost all of the pages:
> [After World War II, he was tried in the Doctors' Trial in Nuremberg, convicted of war crimes and crimes against humanity, and was condemned to life imprisonment. His sentence was reduced to 15 years in 1951 and he was released in March 1954. Fischer subsequently regained his license to practice medicine and started a new career at the chemical company Boehringer in Ingelheim, where he stayed until his retirement.
](_URL_2_)
and
> [At the third Ravensbrück Trial in April 1948, the British court handed her a sentence of life imprisonment. It was estimated that she had selected 3,000 women prisoners for the gas chamber and other execution methods. Rabe was released from prison on February 26, 1954, having served five years and ten months in confinement.](_URL_1_)
| AskHistorians | https://www.reddit.com/r/AskHistorians/comments/5xt81u/why_were_so_many_nazi_war_criminals_released_very/ | {
"a_id": [
"deldcox"
],
"score": [
8
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"text": [
"Not only were Nazi war criminals released relatively early into their sentences, but also Japanese war criminals. This largely took place in the mid-1950's, not only by the United States, but the majority of the Western Allies, who realised that there was limited political value in holding war criminals, who were seen as a relic of the immediate post-war disgust by the Allies of atrocities committed by the Axis forces.\n\nWhile there continued to be a desire to punish those who had committed such atrocities, it was also countered by a perceived need to move on from the war, and engage in the Cold War. \n\nEspecially in regards to Japanese war criminals, it was felt that releasing them would strengthen ties to Japan, and limit the perception of a punitive occupation. While I don't have similar sources for Nazi war criminals, it seems likely that the Western Allies held similar conceptions in relation to West Germany, which was the centre point of the Cold War at the time. \n\nAnother aspect was that the Soviets still had a large number of German POWs at the time. By releasing war criminals early, the Western Allies were able to claim that they had legitimate claims to representing freedom and international cooperation. The influence of international religious and pacifist organisations also influenced diplomats and politicians, as well as the general public, with a growing campaign for clemency. \n\nSources:\n\nWilson S., Cribb R., Trefalt B., and Aszkielowicz D., \"Japanese War Criminals and the Politics of Justice, 1945-1958\" 2017.\n"
]
} | []
| [
"https://en.wikipedia.org/wiki/Category:Nazi_war_criminals_released_early_from_prison",
"https://en.wikipedia.org/wiki/Margarete_Rabe",
"https://en.wikipedia.org/wiki/Fritz_Fischer_\\(medical_doctor\\)"
]
| [
[]
]
|
|
127uc8 | Sports in History | In your period of interest what was the most played/popular sport among the people? What were the rules? Equipment used? Frequency of games? Have at it! | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/127uc8/sports_in_history/ | {
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"text": [
"Goodness, where to begin...\n\nIn 1770s-1780s Canada, though not competitive, people loved \"carioling,\" a form of sled dragged by horses. Ice skating was also very popular, though hockey wouldn't be invented for another century.\n\nIn the Thirteen Colonies, there were many sports played. One of the most popular was [rounders](_URL_2_), a predecessor of baseball. Trap-ball, or [bat and trap](_URL_1_), was also a popular game, where the batter would smack the trap, popping the ball into the air, and then whack the ball toward the opposite team, who tried to catch it.\n\nBritish soldiers during the Revolution played an early form of croquet, but cards and [teetotum](_URL_0_) gambling appears to have been more popular.",
"Cricket. In the army twentieth century, everyone in the West Indies played cricket. For men, there were vast numbers of teams ranging from highly competitive clubs to social groups based around villages or farms. Even women could play - Learie Constantine rated his own sister as a good club-level wicketkeeper.\n\nGames were played whenever possible, though usually on weekends. In major grounds, like the maidan in Kolkata or the Queen's Park Savannah in Port of Spain, as many as seven or eight games could be played simultaneously. Even small villages would turn out a competitive XI.\n\nEven children started young. Garry Sobers, the greatest cricketer ever, honed his accuracy as a child when factory workers would put a penny on a stump and challenge him to hit it with a ball. Kids who were too poor to buy bats and balls would play with unfold fruit and sticks. \n\nI'm not sure if there's ever been a period or place in which a single game so utterly dominated cultural and social life. The anthropologist Orlando Patterson even suggested that West Indians hate cricket, with its symbols of white authority and British rule, yet compete so fiercely as it was one of the only areas in which they could challenge the colonial masters on a level playing field (no pun intended!).\n\nUnsurprisingly, one of the most influential books in the Carribean is *Beyond a Boundary*, by CLR James - perhaps the only instance of Marxist sportswriting in existence...",
"Related:\n\n[What were the most popular sports in your fields (pun totally intended)? Is the game still around? How has it changed? Why did it die?] (_URL_3_)\n\n[What were and where were the earliest known sports and tests of skill?] (_URL_2_)\n\n[Over the last few centuries, how did organized sports grow from a pastime, to the crazy multi-billion dollar industry that it is today?] (_URL_1_)\n\n[Why isn't Soccer the most popular sport in the former 'white' dominions of the British Empire?] (_URL_0_)",
"As Ken Burns describes it, everyone (lots of Americans) played baseball in the 20s. Indeed, even the Klan played baseball. They played Negro League minor league teams or other barnstorming, racialized teams, like the Hebrew All-Stars. They may have even had their own league in the 1950s. They may have had a league in the 1920s, which seems very likely considering the ambiance, but I have not found much that suggests that they did. ",
"Currently writing my senior thesis on how modern football developed in England through the country's political transformation from 1860-1906. Interesting to see how football would edge out cricket and rugby to become the dominant spectator sport among the working and middle classes."
]
} | []
| []
| [
[
"http://www.gamesmuseum.uwaterloo.ca/VirtualExhibits/Brueghel/teetotum.html",
"http://en.wikipedia.org/wiki/Bat_and_trap",
"http://www.mastersgames.com/rules/rounders-rules.htm"
],
[],
[
"http://www.reddit.com/r/AskHistorians/comments/yzglf/why_isnt_soccer_the_most_popular_sport_in_the/",
"http://www.reddit.com/r/AskHistorians/comments/wy8j8/over_the_last_few_centuries_how_did_organized/",
"http://www.reddit.com/r/AskHistorians/comments/qo5k7/what_were_and_where_were_the_earliest_known/",
"http://www.reddit.com/r/AskHistorians/comments/11btfw/what_were_the_most_popular_sports_in_your_fields/"
],
[],
[]
]
|
|
38y3yx | Please steer me in the right direction about Civil wars in Republican Rome | How did civil wars cause the end of the republican rome? Sources i could visit? a general gist of what happened? I have a ten page paper to write and i really don't know anything about this topic | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/38y3yx/please_steer_me_in_the_right_direction_about/ | {
"a_id": [
"cryrwuh"
],
"score": [
3
],
"text": [
"Could you elaborate a bit?\n\n* What's the paper for?\n* Where have you searched for sources?\n* What have you found so far?\n* What do you know already? (You do know *something*.)\n\nAnything else you may think is relevant. "
]
} | []
| []
| [
[]
]
|
|
313f15 | how does diet coke cause cancer? was that just media hype for a while, or is there legitimacy behind it? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/313f15/eli5_how_does_diet_coke_cause_cancer_was_that/ | {
"a_id": [
"cpy3fl2",
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2
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"text": [
"Diet Coke contains Aspartame, which is an artificial sweetener that many people believed for a long time helped contribute to cancer, specifically brain cancer.\n\nWhile there are people that will argue this is true and swear by it, the overwhelming majority of the medical industry believes that it is not carcinogenic in any way if consumed at levels that are likely in everyday life.\n\nThis is intuitive because Aspartame breaks down into Aspartic Acid, Methanol, and Phenylalanine in your small intestine before it is absorbed into your blood stream. All 3 of these things are likely to be found in higher concentrations after you eat a steak, for example. So unless you think steak causes cancer, it isn't any more likely that Aspartame does.\n\nPlease don't confuse this as saying that Aspartame is completely harmless, or that it's even effective as a dieting aid; it just doesn't cause cancer.\n\n\nTL;DR Either steak causes cancer too, or neither do",
"It contains Saccharin and Aspartame/Neotame sweetners.\n\naspartame was found to cause cancer in rodents in the 70s those results are disputed and it is considered OK for humans"
]
} | []
| []
| [
[],
[]
]
|
||
fh3muh | clueless about economics. how will the dow dropping 1,400+ points today and a potential recesssion/etc affect everday working people like me? those who aren't wealthy. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fh3muh/eli5_clueless_about_economics_how_will_the_dow/ | {
"a_id": [
"fk8l5e9",
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"score": [
2,
4
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"text": [
"Jobs may begin to slow down due to worry or lack of funding. Because of this your employer may limit hours or lay people off.",
"Immediately, it won't, outside of any 401k you may have. If the market rebounds within a month or so, you probably won't see much impact overall. If the drop lingers, then you can see potential layoffs and reduced hours from employers."
]
} | []
| []
| [
[],
[]
]
|
||
5yzjlo | The rule of India by East India Company is famously cited as a case of Corporation ruling an entire country. How did this work in practise? Did they separate their Commercial activities and Governance? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/5yzjlo/the_rule_of_india_by_east_india_company_is/ | {
"a_id": [
"deu5jgt",
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44,
26
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"text": [
"Follow up question: what was the British people's opinion of this rule by the East Indian company? Did they have any anxieties about a company having so much power or was it mostly just accepted?",
"Follow up question: what was the construction that the Indian population held regarding the Company? Did they understand that it was not the British Government, or make no difference between government and corporation?\n\ne: phone typos"
]
} | []
| []
| [
[],
[]
]
|
||
1d51ia | Do worms have a home? | I often see worms try to cross pavement and other hard surfaces, especially when it rains. This leads to them getting stepped on, so I sometimes pick them up and throw them in the grass when I notice them. Am I screwing them over? Are they following some path (like ants do with pheromones, for example)?
| askscience | http://www.reddit.com/r/askscience/comments/1d51ia/do_worms_have_a_home/ | {
"a_id": [
"c9n6eoy"
],
"score": [
2
],
"text": [
"They just kind of roam around eating tasty soil. No set place of residence other than the entire patch of soil they came off of"
]
} | []
| []
| [
[]
]
|
|
25se4n | How much difference was there in the way different ancient Mediterranean people dressed and clothed themselves, before the dominance of the Roman Empire? | Specifically interested in the difference between the people of Carthage and of Rome, before the punic wars were over | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/25se4n/how_much_difference_was_there_in_the_way/ | {
"a_id": [
"chkfipw"
],
"score": [
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"text": [
"Unfortunately I can't give you a very full answer at the moment as I am away from my computer for today, but I can write something more detailed tomorrow. Until then, I would recommend this website: _URL_0_\n\nAlong the side you can see there is a section dedicated to costume. It does not deal with North Africa but many of the same issues apply. One of the major problems is that we have only very scattered information on what \"the man on the street\" wore, as clothing does not preserve, and so we are dependent on portraits. As is the case today, clothing in a portrait does not necessarily reflect everyday ware."
]
} | []
| []
| [
[
"http://www2.rgzm.de/transformation/home/FramesUK.cfm"
]
]
|
|
g74jp | What is the fastest you can move, taking into account relativity? | Moving from point A to point B, you could theoretically move at .9999c. But, if you do you'll have made it so that people at point B are old and grey when you get there. Moving just under the speed of light means that from your perspective you are moving as fast as possible, but from the perspective that makes a difference, you are actually moving quite slowly. Sure, you'll feel like you got to your destination in no time at all, but the same could be said for falling asleep on the bus. So, if you have a magical "go infinitely fast" machine and an appointment 10 miles away, what is the theoretical least amount of time needed to get there? | askscience | http://www.reddit.com/r/askscience/comments/g74jp/what_is_the_fastest_you_can_move_taking_into/ | {
"a_id": [
"c1ldult",
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"score": [
5,
2
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"text": [
"Massive objects can get asymptotically close to the speed of light given enough force.",
"An observer at your destination (your \"appointment\" location) would probably have a hard time distinguishing you traveling at 99.999% the speed of light and the speed of light itself. \n\nSo, to directly answer your question, an observer 10 miles away could not see your trip take less than 10 miles / 186,282.397 miles per second (about 53 microseconds). As you say though, this trip could feel arbitrarily short to you, depending on how fast you go. "
]
} | []
| []
| [
[],
[]
]
|
|
20b4md | POW mail in WWII: were mail ships neutral or was mail routed through neutral countries/states, or... | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/20b4md/pow_mail_in_wwii_were_mail_ships_neutral_or_was/ | {
"a_id": [
"cg1lqok",
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"text": [
"I believe this was answered in another thread, so to make a long story short, the [Red Cross did most of the leg work of delivering mail to prisoners of war](_URL_1_), at least in the European theater. Mail would be routed through a neutral country such as [Portugal, Switzerland or Sweden] (_URL_0_), then sent on to the POW camps, typically by rail. As the Red Cross was considered an illegitimate target by all belligerents, RC shipments were considered to be out of bounds for targeting. However, due to the fact on the ground that most shipment lines were used for military purposes as a priority, RC shipments could and would occasionally be destroyed. \n\nThis model was attempted in the Pacific, however, the Japanese had not signed on to the different Conventions regarding treatment of Prisoners of War, and it was much more difficult for the RC to get supplies or correspondence to them. ",
"Previously discussed here: _URL_0_"
]
} | []
| []
| [
[
"http://www.med-dept.com/powFood.php",
"http://www.historylearningsite.co.uk/red_cross_and_world_war_two.htm"
],
[
"http://www.reddit.com/r/AskHistorians/comments/1pg80z/how_was_correspondence_handled_between_axis_and/"
]
]
|
||
3c9nat | what is this 'google dream code' thing i keep seeing every where and what is it used for? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3c9nat/eli5_what_is_this_google_dream_code_thing_i_keep/ | {
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"Think of your own brain, and imagine you are five (slaps knee), lying down on a field of grass looking up at all of the funny shaped clouds in the sky.\n\nYou notice one cloud looks like something, but you can't quite put your finger on it. You think of every single thing you've ever seen in your life that kind of looks like this cloud, and naturally, this takes you awhile because you're young. Finally, after a bit, you realize that this cloud looks like a dog! So you start imagining dogs in all of the funny scenarios you've seen them in, until you notice another cloud you want to think about next. \n\nThis is a pretty good analogy of what's going on in [Google's DeepDream project](_URL_1_). Essentially, Google made an [artificial brain](_URL_3_) modeled after our own and is testing how much this brain knows by feeding it \"cloud images\" and seeing what it thinks about. You know how you thought that cloud looked like a dog? Well, perhaps at five years old, you were really into dogs and hence know a lot about them. Same thing with DeepDream: If you give it a \"cloud image\" and it outputs a bird-like image, then you know that this artificial brain in particular must be \"trained\" to know what birds look like, especially if you have a bird-like cloud in your cloud image.\n\nThe important thing to realize is that these \"cloud images\" do NOT have to be pictures of clouds! They can be anything: a selfie of yourself, a landscape picture, etc. The artificial brain will essentially just emphasize the features it's been trained to recognize. If you look at the [example gallery](_URL_0_), you can see some pretty psychedelic results. The purpose of this project is mainly for researching and improving these artificial brains, and making them better for more applicable things in the future.\n\n**TL;DR** Google made a robot brain and is seeing what it recognizes by giving it \"cloud images\", and examining the results so they can make the brains better.\n\n[Google gives a more complicated and thorough explanation of all of this in their research blog!](_URL_2_)\n\n"
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"https://github.com/google/deepdream",
"http://googleresearch.blogspot.ch/2015/06/inceptionism-going-deeper-into-neural.html",
"https://en.wikipedia.org/wiki/Artificial_neural_network"
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1wmkg8 | Why did elevated beds arise in some cultures while others use beds low to the ground? | For example the Western bed frame vs. a Japanese futon. I'm sure there are other examples, I just don't know of them. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1wmkg8/why_did_elevated_beds_arise_in_some_cultures/ | {
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"**EDIT: /u/extesser is right, it's mostly dominated by heat conduction and not a temperature gradient. I'll leave the post untouched for the history books, since it sparked some interesting replies!**\n_________________________________________________________\n\nI can only speak for the Vikings in Norway. Temperature is one reason for why it emerges. Cold air sinks, hot air rises. \n\nIf you're a Viking living in a longhouse(ref: _URL_0_ ), sleeping on the floor might just kill you. Get up on a bench, and you're much better off. \n\nIdeally you'd want to stay up against the roof if you wanted to stay as warm as possible - but smoke from the firepits collect there so the practical middleground would be benches or elaborate furniture with legs. \n\nI can't speak about what they do in the tropics, but I know from personal experience that bugs alone make elevated beds an attractive solution.",
"I can speak for Middle Ages Nobility; Beds were raised about a foot off the ground to deter mice from nesting under them. If a bed was too low to the ground, the small crack could attract mice, rats and other creatures for use as a nesting spot.",
"i can only speak for Bedouin culture, but sleeping on mats, rugs, and furs is common until today, necessitated by the fact that they live a nomadic lifestyle, so rolling up your bed and throwing it on the back of your pack-animal is infinitely more convenient and practical than, say, disassembling and lugging around a four-post bed. Also, the air is slightly cooler on the ground, and that's where the drafts are felt."
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sp8to | If a mosquito bites a person who is HIV positive, then bites me, will I become HIV positive? | If a mosquito bites a person who is HIV positive, then bites me, will I become HIV positive? | askscience | http://www.reddit.com/r/askscience/comments/sp8to/if_a_mosquito_bites_a_person_who_is_hiv_positive/ | {
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"Almost assuredly not.\n\n_URL_0_",
"[This](_URL_0_) is a pretty good answer."
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6o0xcl | if california's housing market is already incredibly overpriced, why does it keep rising? | The median cost of a home in Cali is now more than twice the national average and homelessness is rising, how is demand still surging? Aren't they running out of middle-class homebuyers? Are they used as income properties or other form of investment? Please explain. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6o0xcl/eli5_if_californias_housing_market_is_already/ | {
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"Because the economy is still very strong, particularly in the Bay Area, people keep moving there. Home prices will drop once people stop wanting to move to California",
"The core places that have growing home prices (commute-ready homes in San Francisco, fashionable areas of LA, beach property) are limited in their supply and have a continuously growing number of wealthy people wanting to buy them.\n\nAs an example, lets look at San Francisco: The city has a fixed size because of the land it's on, and only a certain number of homes are within a reasonable commute time of the downtown core. S.F. also has very restrictive zoning laws, meaning new high rises are very difficult to build. With that, only a certain number of people can live within a comfortable commuting distance of their jobs.\n\nS.F. is also a hotbed of technology, a very high growth and lucrative field to be in. People are able to make a lot of money at it, and more people want to move to the area to join in on that business.\n\nMore money floods into the area, but there aren't homes for them. So, the people with money get into a bidding war driving up overall home cost.",
"Uneven distribution of income... there are a selection of the population doing very well, making high incomes, seeing their stocks/options appreciate in value. And high earners tend to marry other high earners, doubling down on their buying power. And they are willing and able to bid up prices for housing in the most in-demand areas. This has a snowball effect, as prices rise in SF and LA then it impacts everything further and cheaper as people have to move further away to afford anything. The issue is that there is still way less supply than there is demand so there are more buyers (or potential buyers) than there are homes being built. Thus people are often spending more than budget guidelines suggest one should spend on housing, cutting spending elsewhere or taking on additional debt.",
"Supply and demand. More people want to live there than there are places to live. \n\nThe two obvious next questions are \"Why is the supply so low?\" and \"Why is the demand so high?\". \n\n**Why is the Supply so low?**\n\nShort answer: Few people actually want it to rise. \n\nThe current homeowners don't, because their home price keeps going up with less competition. A lot of the \"original\" residents don't, because they want the city to retain it's quaint, artistic charm and not be dominated by skyscrapers. The will of these people is expressed in restrictive regulations, and because of them, the only new housing that makes money is luxury housing. (Because if a place is expensive to build, it will be expensive to rent.) People rebel against this, dragging it out in court for years or just torching the construction sites, so the supply is not keeping up with the demand. The root cause is frankly that a lot of people there don't understand or believe basic economics. There's actually no such thing as a \"luxury house\". (You can buy a mansion in Detroit for $1.) It's all just supply and demand, and by preventing new housing from being built, _every_ house is turning into a \"luxury house.\" A normal-looking 1 bedroom, 900sqft single-family home in the city recently sold for $3 million.\n\n**Why is the Demand so high?**\n\nThe tech industry and foreign investors. \n\nTech pays big bucks and is still booming. The average starting salary is $90k and I personally know a guy who took a $400k pay CUT in order to work in a cooler part of the industry. People there are loaded. \n\nForeign investors have also jumped in, raising the demand even more. They see the problems with the supply of housing, so it's a no-brainer to invest. \n\nSo there's tons of demand and the supply can't keep up. This makes prices ridiculous.",
"Prop 13 also has distorted the market significantly. You can find dozens of articles about it, but it effectively freezes property taxes to time of purchase as opposed to annual assessment. This incentivizes home owners to not sell because a house bought many years ago is a huge tax shelter. This also causes shenanigans like creating shell companies so that no more than one party \"owns\" more than 50% of a property to keep the property tax bill low. \n\nMalcolm Gladwell gives a fun example of this regarding LA golf courses. They pay a tiny fraction of the taxes normally owed on the value of their property. Revisionist History - A Good Walk Spoiled: _URL_0_"
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7gmxo7 | When a person loses their vision in one eye, is their loss of depth-perception permanent or does the brain find a way to adapt? | askscience | https://www.reddit.com/r/askscience/comments/7gmxo7/when_a_person_loses_their_vision_in_one_eye_is/ | {
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"There are many monocular cues to depth such as parallax, relative size, atmospheric perspective, etc. you can find a list [here](_URL_3_). Some of these are both relative cues (something is farther away than something else) and some are absolute (something is this far away). If you close one of your eyes, the world doesn't suddenly seem totally flat. However, binocular cues like binocular disparity can lead to some special sensations of depth like [stereopsis](_URL_1_). Consider the difference, for example, between looking at the objects on the table in front of you and the experience of seeing them at different distances vs. looking at a photograph of the same table in which you can tell which objects are nearer and farther away, but it lacks the same sense of depth. Or, if you've ever been to a 3D movie, the difference between that and a 2D movie. The sensation of something coming off of the screen toward you is caused by stereopsis from binocular disparity, which occurs when light from objects falls on different relative positions of your retinas. This is the same principle behind the [stereoscope](_URL_0_). However, even with a single eye you can approximate this by moving a picture side-to-side quickly so that it falls on different positions of the same eye. This is sometimes called [wiggle steroscopy](_URL_2_). \n\nSee [this](_URL_4_) recent post on the same topic. "
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1cry92 | When / why did it become a custom to put your hand on your heart for patriotic moments (specifically US pledge of allegiance and national anthem) | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1cry92/when_why_did_it_become_a_custom_to_put_your_hand/ | {
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"The hand over one's heart is a civilian salute. It is for use by civilians (people who are not in a nation's armed forces) at moments that would be appropriate for a military salute.\n\nSome countries (the US, Italy, etc.) use the hand over the heart as a civilian salute, some (Latin American countries for example) have different civilian salutes - like the hand across the chest with the palm facing down - while others (UK, Canada) have no official civilian salute.\n\nIn the US, prior to 1942, the Bellamy Salute (similar to the Roman/Nazi salute) was the official civilian salute.",
"The civilian pledge of allegiance used to be accompanied by the 'Bellamy salute' which was based on the 'Roman salute' (NB - there's no hard evidence of this ever having been used in this way in Ancient Rome, but it was part of popular historical myth, much like the thumbs up/thumbs down gestures) This Bellamy suit involves pointing a fully stretched out arm, with the palm facing downwards and the finger touching, toward a flag or other symbol. In 1942 congress chose to make the Bellamy pledge the official national pledge, however some recognised how uncomfortably close the gesture was to the Nazi salute and the hand on heart alternative arose. This is often attributed directly to Roosevelt but again there's scant hard evidence of this. It was also referred to as 'The Lincoln Salute' and attributed to the saluting style of Abe, but again, this seems to be popular mythology rather than solid historical fact. \n\nThere were a few possible non-American sources, the Albanian military salute is the same and dates from the 1920/30s and the gesture is found in traditional greetings in some Arab societies. \n\nThe next major change came in 1953/4 when Senator Homer Ferguson sponsored a successful bill to add the words 'under God' to the Pledge.Something Bellamy's granddaughter said he would have opposed. \nNote that the flag code states that for civilians the hand 'should' go on the heart, the use of 'should' rather than 'shall' means that it is not compulsory and no legal sanctions may be applied for not performing this gesture. \n\n\n\nThis blog entry has photos from the Library of Congress of Children performing the old Bellamy style salute as late as 1942. \n_URL_0_ "
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9k69qk | I know why the inter-war Germany was called 'Weimar Republic', but who started using that term? And when? And did it have a positive/negative connotation? | I obviously know the history behind 'Weimar' (It being the place where the assembly met and the constitution was drafted) but when did the term became common in usage? I heard that Hitler popularized it late in its short existence?
For me it is easy to imagine that a national assembly which had to relocate because of popular uprisings would be ridiculed for that. Based on that assumption it isn't far to guess that the term always had a negative connotation.
But today it is used interchangeably without major differences on all ends of the political spectrum. Maybe someone can enlighten me? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/9k69qk/i_know_why_the_interwar_germany_was_called_weimar/ | {
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"The name \"Weimar Republic\" was not really used much during the existence of the Republic. The Republic used \"Deutsches Reich\" as the official name, and \"Republik\" in various compounds, but Weimar was an informal title at best. Some Anglophone publications used Weimar Republic yet this was typically a minor naming convention. The actual town of Weimar had a rather strained relationship with the Republic. It was the site of the Republic's constitutional convention, chosen mostly because it was away from the chaos of Berlin, and the was the center for Gropius's Bauhaus movement. Yet the largely conservative Weimar population had little love for the Republic and many locals resented the Bauhaus for bringing in foreigners and Jews into Goethe's birthplace. Hitler and the NSDAP though were the ones who popularized the name Weimar Republic, and he and other NSDAP propagandists used it as a slur. The name stuck after 1933 and filtered into opponents of the regime as well as outside of Germany. This [google Ngram](_URL_1_) for English shows the post-1930 pickup, as does this [Ngram](_URL_0_) for \"Weimarer Republik.\" As both Ngrams indicate, the Weimar Republic clearly became the \"Weimar Republic\" after 1945. \n\nThe fact that historians and other writers use Weimar Republic when the actual government in question did not is not terribly unusual. There are other examples of Anglophone names that are anachronistic or inaccurate. The Polish-Lithuanian Commonwealth is one, as is the Byzantine Empire. One notable example that sometimes strikes pedants is the use of Tsar after Peter I. Peter I accepted the title All-Russian Imperator in 1721 and it became the first title used by subsequent Romanovs. This was part of Peter I's efforts at building up his prestige and self-styling as a modern European monarch who had no peers. The tsar title implied he was still Muscovite, but imperator is a more ambitious. Subsequent Romanovs would use the imperial title as their main title, and tsar became relegated to various monarchical appendages that signified areas over which the tsar had suzerainty, such as the Tsar of Kazan, Tsar of Siberia, etc. The title Tsar also entered into the vernacular as a shorthand for the Russian ruler in the non-Russian world, but subsequent emperors after Peter I sometimes preferred Tsar over Emperor, such as the archconservative Alexander III."
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"https://books.google.com/ngrams/graph?content=Weimar+Republic&year_start=1800&year_end=2000&corpus=15&smoothing=3&share=&direct_url=t1%3B%2CWeimar%20Republic%3B%2Cc0"
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36w0xr | Who were the most influential figures in the Bolshevik Party who weren't executed during the purges? Why did Stalin spare them? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/36w0xr/who_were_the_most_influential_figures_in_the/ | {
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"I think most influential is pretty subjective and the range of purges meant pretty much everyone who -was- overly influential and famous got purged. And the remainder of the Communist party in the aftermath of Stalin's purges was absolutely subordinated to him (with the possible exception of Beria)\n\nThe closest I can think of would be someone like Anastas Mikoyan. If you look at Soviet Politburo membership list basically everyone on it from 1917-mid 1930s who wasn't firmly on Stalin's side all the way through got shot."
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vk0mt | French Colonies Gone Wrong | I am not an historian, but I have noticed (through discussion both IRL and here) that the former French colonies are significantly more screwed up than the other former colonies of major European powers. First, is this true or am I making it up, and second, why? What did the French do differently causing their colonies to end up so damaged?
Edit: You all are awesome! It seems that overall France wasn't any worse than the rest of the colonial powers. Now I'll try and figure out why I thought that. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/vk0mt/french_colonies_gone_wrong/ | {
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"It is hardly just France, The Belgian Congo and Portuguese Angola are hardly examples of successful states. For every successful colonial state you can point towards another that has been unsuccessful. ",
"Vietnam is doing pretty well. Probably would have been doing better if it wasn't for that whole business with the Americans. French Arab Africa isn't doing too poorly, could be doing better, but could certainly be doing better.\n\nProblem is that most of France's colonies were in Western Africa, which regardless of whose colony they are, they are doing pretty terribly.\n\nSome Colonies also saw more development/ settlement than others, the ones that were more settled and developed are doing better than the ones that were just exploited to its fullest extent possible. In this category I would also put the colonies that were already more settled and civilized when they Europeans came like in India and Asia.",
"Cote d'Ivoire was doing pretty good for a while.",
"Canada's pretty sweet. ",
"On Africa:\n\nThere are no simple answers to this type of question; there are only complex, contentious, and often outright speculative ones. \n\nFirst, don't think the French were particularly inept or that their empire was uniquely pernicious. That isn't a case you can make with intellectual honesty. You may hear \"Anglophone\" countries are doing \"better\" than \"Francophone\" countries, though to my mind that's a bit like saying the Milky Way is doing \"better\" than Andromeda: it makes no sense.\n\nIn actuality, there are myriad reasons why things are the way they are. The CFA (currency in the region), resource availability, ethnic strife, and population demographics all play a part. Geography is more important than former colonial overlords.\n\nNow, some would argue that France's continued close ties to its former African colonies - its meddling, if you will - have worked against African business and governance, but again, this is a very contentious idea.\n\nEdit: I wrote this response on my phone in the middle of the night, so I just went back through and corrected a couple of things.\n\n\n\n",
"It may be because the French, when creating colonies, were not aiming to create a separate identity, but rather to almost literally transplant feudal/pre-Revolution France into the colonies. This included their culture, language, and most importantly, their caste system. The church on top, followed by government, followed by the wealthy landowners, followed by peasants. This was both inflexible and archaic, and was doubtlessly an economic and social issue for the colonies. Furthermore the embedding of the French culture created very pro-France atmosphere, so there was no real desire or need for the colonies to grow or become self-sufficient ( For example, the U.S managed to develop an identity separate from that of Britain in only a few decades, whereas many people in present-day Quebec still consider themselves French. Furthermore, they only received independence from France at the barrel of English guns) \n\nAnother possible factor may be that the Catholic Church forbade giving firearms to people who were not white. This caused some serious issues because the French could not supply sympathetic natives with firearms to support them (The demise of Huronia is a good example). This likely did not work in the favour of France when fighting or even forming allies with the natives, harming the colonies as a whole.",
"England went pretty well.\n\n(this is a joke)",
"I'm not buying into the premise, tbh. \n\nFor example, take the 10 countries with lowest GDP/capita:\n\n1. Congo, formerly Belgian.\n2. Liberia, no colonial past.\n3. Zimbabwe, formerly British.\n4. Burundi, formerly Belgian.\n5. Eritrea, formerly Italian.\n6. CAR, formerly French.\n7. Niger, formerly French.\n8. Sierra Leone, formerly British.\n9. Malawi, formerly British.\n10. Togo, formerly German and French.\n\nThat's not a particularly French-dominated list. More of a list of random places in Africa, where the French happened to have a lot of colonies.",
"I will only talk about France's colonies here, but let me answer your question in separate steps. \n\nFirst, let's examine the French Colonial Empire. Here are the regions ruled over by the French: Maghreb, Sahara, much of West Africa, 70% of the continental US, Madagascar, French Guyana, Vietnam, half of India, French polynesia, Nouvelle Caledonie, Syria, Quebec, and many other small islands.\n\nI absolutely disagree with your statement that \"the former French colonies are significantly more screwed up than the other former colonies of major European powers\". I don't really know how you can say that England's colonies are \"much better off\". Regarding the bulk of the French colonial Empire (Africa), I think the problems there are caused by factors on the ground (that European powers may certainly have had a role in implanting), but I can't see a harmful thing that was unique to France. Regarding what people have said might have been the \"French Ideology\" in colonies, I think you'd have to be much more specific on the time period. Yes, the French wanted to implant their ideology and way of life in their colonies, but they realized later that it wasn't going to work. As a result, they turned to a more \"productive\" relationship with their colonies, especially in the 20th century. Algeria was a special case, because it wasn't considered a colony but a region of France itself. \n\nThere is nothing harmful that the French have done to their colonies that the other powers didn't do. In areas where the French influence has been significant, it's fair to say France has kept a serious relationship with those regions, and are willing to help them to a certain extent. I want to come back to Africa to end this, because it's the most prominent francophone region. While french colonization has had terrible effects on the local population (but they are *not* solely found in French colonies), you have to recognize what the French government brought to those countries. They educated the populations, eradicated deadly diseases, set up a sizable Health-care infrastructure, and built roads, railroads, etc...\nAll of this while *the African colonies are estimated not to have brought any money for France itself*. While they supplied manpower and raw resources, they have not directly made France richer (just wanted to point that out). \n\nSo, to come back to your question, it's unfair and wrong to say the French \"damaged\" their colonies. They took care of them, and were is some regards fairer than other powers (Belgium in the Congo). I think the main problems that stemmed from colonization was the rather dysfunctional system of government the countries inherited (corruption, etc...) and the fact that the borders of countries today do not follow ethnic patterns. Algeria is a category appart, and it is the only region where it is fair to say the French have had a big negative influence (largely due to the War). Other than that, **you cannot say that the French have screwed up their colonies**."
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e7wo35 | when two tvs in tvs same house are run through the same cable service, why does one seem to always lag behind the other? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/e7wo35/eli5_when_two_tvs_in_tvs_same_house_are_run/ | {
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"A modern TV contains electronics which decode the digital HDMI signal and then turn it back into a picture and sound. Unfortunately these usually introduce a delay, and on some models it can be a notable fraction of a second, and it's not a standardized amount."
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ohc49 | What actually is going on as electrons move through a circuit? | I'm trying to understand the physical details of current more thoroughly. Let's consider a simple example with a battery and a resistor. Electrons are "flowing" from - to +.
But what does that mean? Are the excess electrons at the negative terminal leaving that terminal? If so, how do they propagate through the wire? Or is it that they are repelling the free electrons in the material, who in turn repel more electrons, creating a sort of ripple effect?
What about when the electrons encounter the resistor? Is it that electrons are actually lost when we talk about dissipating voltage? Or is their propagation just impeded?
If so one could break this down for me in understandable detail, I'd appreciate it! | askscience | http://www.reddit.com/r/askscience/comments/ohc49/what_actually_is_going_on_as_electrons_move/ | {
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"The best way to think of it is that the electrons in a wire are moving because of the electric field in the wire. The electric field is established in the wire when you connect it to the battery terminals, and the speed at which it propagates through the wire is the speed of light in that wire (or circuit). \n\nYou're basically right about the resistor; the propagation of electrons is impeded in that they scatter off impurities and such, causing the electrons to lose energy and the resistor material to gain thermal energy.",
" > Or is it that they are repelling the free electrons in the material, who in turn repel more electrons, creating a sort of ripple effect?\n\nBingo. The electrons themselves travel very slowly through the wire, but the propagation wave of 'repulsion' travels near c (around 0.5c in copper)."
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mqh35 | why can't leaded engines use unleaded petrol? | I've asked this question for years, and I have gotten two different answers for it. One is that the lead lubricates the cylinder walls, and the other is that the lead reduces the temperature of the burn, allowing the engine to run cooler. Is either of these correct, or is there a different answer? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/mqh35/why_cant_leaded_engines_use_unleaded_petrol/ | {
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"Neither of those is correct. The leaded gasoline vapor can be compressed more than unleaded without spontaneously exploding due to the temperature increase. The compression ratio is determined by engine geometry, so an engine designed for leaded gas will compress unleaded gas to the point where it spontaneously ignites, throwing off the cycle and damaging the engine.\n\nEDIT: I didn't explain why they would design for such a high compression ratio. A higher compression ratio generally allows you to be more efficient and cleaner. However, most governments have decided that these benefits do not outweigh the negatives of putting a ridiculous amount of lead in the air.",
"Neither of those is correct. The leaded gasoline vapor can be compressed more than unleaded without spontaneously exploding due to the temperature increase. The compression ratio is determined by engine geometry, so an engine designed for leaded gas will compress unleaded gas to the point where it spontaneously ignites, throwing off the cycle and damaging the engine.\n\nEDIT: I didn't explain why they would design for such a high compression ratio. A higher compression ratio generally allows you to be more efficient and cleaner. However, most governments have decided that these benefits do not outweigh the negatives of putting a ridiculous amount of lead in the air."
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[],
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|
j9msq | From where do we measure distances between celestial bodies? (center-to-center? surface-to-surface?) | Essentially exactly what's in the title. For example if you're saying the earth is on average 1 AU from the sun, then does that mean that the center of the earth is 1 AU from the center of the sun (kind of what I figure) or that the surface of the earth is 1 AU from the surface of the sun.
The reason I ask is [this video](_URL_0_) which made me wonder, if celestial measurement is center-to-center, would any of those planets actually subsume the earth?
a semi-related question I thought of as I was asking my original: if we *were* to measure surface-to-surface (i.e. nearest surface on earth to nearest surface on sun is 1AU) would all of the planets look relatively the same size in that video? | askscience | http://www.reddit.com/r/askscience/comments/j9msq/from_where_do_we_measure_distances_between/ | {
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"It varies. Most celestial bodies aren't \"measured\", their distances are estimated using a variety of techniques.\n\nThe Moon for example can be measured by firing a laser at a small reflector on its surface (left by the Apollo mission) and measuring the time that the laser light takes to make the round trip. So, in this specific case the distance to the Moon is measured to a few inches above it's surface. You could then add it's radius (and the few inches) to find the distance to it's centre.\n\nThe distance to the planets can be calculated using observations of their orbits (Copernicus did this), in this case the accuracy is based on the accuracy of the observations. I don't know how accurate these are these days but I suspect that the error bars are now within the diameters of (at least) the largest planets meaning that a calculation could be made to either centre or surface as required.\n\nRelatively close stars (or other bodies) are measured using parallax, this means that observations are made of how they move relative to background stars and then trigonometric calculations made. It this case the stars are considered \"point sources\" and the distance from their surface to their centre is considered zero. The estimated distances are therefore \"to the star\" with no specification of surface or centre.\n\nParallax has a limited range however, so even further from earth methods such as comparing the brightness of celestial events such as supernova are used. Type 1a supernova occur at the same brightness, so when these are observed the relative brightness can be use to calculate (estimate) distance. The Andromeda galaxy for example is 2.5 million light years away, but again, due to the accuracy of the measurements using this method will have an relatively large error bar.\n\nThere are other techniques.",
"I think the answers provided so far can be fairly misleading. \n\nThe real answer is, the order of magnitude between celestial bodies is SIGNIFICANTLY greater than the size of the bodies. \n\nAnalogy: Lets say you're measuring the distance between two marbles that are 100 feet away from each other. Then you ask - is my distance measurement from center to center or is it from surface to surface? Well, the difference offers you 0.5 inches in precision, but you really can't measure distance to that precision anyway, so you say '100 feet' or '101 feet'. But you don't have it down to the 0.1 inch scale that you can say 'surface to surface distance' or vice versa. \n\njswhitten's response is a good example. He says the moon is 400,000 km away - actually it's 384,000 km away. The rounding error is 16,000 km, which is greater than the diameter of earth! So we're not that precise. Especially when we're talking about the distance to farther planets, because their orbits are elliptical, which results in big error bars in your distances anyway. ",
"It varies. Most celestial bodies aren't \"measured\", their distances are estimated using a variety of techniques.\n\nThe Moon for example can be measured by firing a laser at a small reflector on its surface (left by the Apollo mission) and measuring the time that the laser light takes to make the round trip. So, in this specific case the distance to the Moon is measured to a few inches above it's surface. You could then add it's radius (and the few inches) to find the distance to it's centre.\n\nThe distance to the planets can be calculated using observations of their orbits (Copernicus did this), in this case the accuracy is based on the accuracy of the observations. I don't know how accurate these are these days but I suspect that the error bars are now within the diameters of (at least) the largest planets meaning that a calculation could be made to either centre or surface as required.\n\nRelatively close stars (or other bodies) are measured using parallax, this means that observations are made of how they move relative to background stars and then trigonometric calculations made. It this case the stars are considered \"point sources\" and the distance from their surface to their centre is considered zero. The estimated distances are therefore \"to the star\" with no specification of surface or centre.\n\nParallax has a limited range however, so even further from earth methods such as comparing the brightness of celestial events such as supernova are used. Type 1a supernova occur at the same brightness, so when these are observed the relative brightness can be use to calculate (estimate) distance. The Andromeda galaxy for example is 2.5 million light years away, but again, due to the accuracy of the measurements using this method will have an relatively large error bar.\n\nThere are other techniques.",
"I think the answers provided so far can be fairly misleading. \n\nThe real answer is, the order of magnitude between celestial bodies is SIGNIFICANTLY greater than the size of the bodies. \n\nAnalogy: Lets say you're measuring the distance between two marbles that are 100 feet away from each other. Then you ask - is my distance measurement from center to center or is it from surface to surface? Well, the difference offers you 0.5 inches in precision, but you really can't measure distance to that precision anyway, so you say '100 feet' or '101 feet'. But you don't have it down to the 0.1 inch scale that you can say 'surface to surface distance' or vice versa. \n\njswhitten's response is a good example. He says the moon is 400,000 km away - actually it's 384,000 km away. The rounding error is 16,000 km, which is greater than the diameter of earth! So we're not that precise. Especially when we're talking about the distance to farther planets, because their orbits are elliptical, which results in big error bars in your distances anyway. "
]
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| [
"http://www.youtube.com/watch?v=u1Yi58jtNdY&feature=player_embedded"
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| [
[],
[],
[],
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8vxu8d | why does our heartbeat and blood pressure lower in our sleep and why is it important for our body to do so? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8vxu8d/eli5_why_does_our_heartbeat_and_blood_pressure/ | {
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"* You are lying down. It takes more effort for your heart to pump blood straight up to your brain than it takes to pump when your whole body is horizontal\n\n* Your muscles aren't moving during sleep so they requires less blood\n\n* Your brain uses just as much blood/oxygen when sleeping as when awake"
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[]
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