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56szfd
|
why do all 24 hour cable news networks cut to commercial break at the exact same time?
|
Unlike regular tv that has 30 minute shows ending on the hour or half hour, cable news is on 24 hrs a day yet they all seem to cut to commercials at the exact same random time. If CNN is on commercial you can pretty much bet that Fox News and MSNBC are too. Why?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/56szfd/eli5why_do_all_24_hour_cable_news_networks_cut_to/
|
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"If they had commercials at different times, you could just switch to another channel instead of watching commercials. And that wouldn't really benefit the channel you switch to because you can do the same again when their commercials come on.\n\nSo all channels benefit from keeping their commercials roughly in sync with each other.",
"I remember when TBS had their entire schedule on a 5 minute delay. \n \nIt was smart. made sure i switched to TBS when other channels went into their first breaks, because a TBS program was likely only just starting."
]
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|
[] |
[] |
[
[],
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1lrouu
|
About seismic activity: would a series of small quakes release enough pressure to prevent "the big one"?
|
My understanding of geology/seismology/plate tectonics is amateur at best. I live in California, so obviously I am concerned just a little bit about this sort of thing. I have studied physics but do not know if this is a logical conclusion. Supposing that an area above or near a fault line has a recent history of minimal seismic activity, does this imply that the plate below is incredibly solid, and stable, and not ready to subduct or break or slip? If the pressure increases over time, with still no quakes, does this delay mean that the release of pressure will be greater? And would a steady sequence of quakes magnitude 3.0 or smaller be, in effect, scooting the plate closer to where it will one day rest?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1lrouu/about_seismic_activity_would_a_series_of_small/
|
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"I can only give an armature answer to this at best but let me see. The cause of earthquakes along faults are a release of energy. In California almost all of our faults are transform, which means they slide last each other, specifically to the right if you looked across the fault line. Though there is a certain amount of rock overlying other rock but lets not complicate things. There are also far more faults than you might imagine there to be all over California. As the Pacific plate moves alongside the North American plate you can imagine the rocks being pulled but they are rocks and don't just slide easily. They stick to some degree until enough energy has built up for the rock to release and shift slightly. Imagine trying to push two rocks together as hard as you can and then trying to slide one while keeping pressure. \n\nNow a good way to think of the big earthquake is if you imagine what it is like to slowly snap a stick. The wood will crackle before it finally gives way under your force. The little crackles are like the little earthquakes before the big final release of energy. They predict a large earthquake will follow a series of smaller earthquakes. It is possible for smaller earthquakes to release a good deal of energy but the plates show no signs of ceasing to move past each other so this energy continues to build within the crust. ",
"I'll try keep it short. Yes, it would, but not in the Bay Area because there is too much pressure built up. Similar to the wood analogy the earth creaks and cracks. It depends on your location too. Certain bedrocks behave differently. Some are like the wood and snap, others are like that plastic clip on a bic pencil that you play with in class. Some places intentionally inject water into fault zones to create small earthquakes so they can prevent a large devastating one. \n\nSource: geologist",
"Smaller earthquakes do not actually prevent or appreciably delay a larger earthquake; however they can indicate a possible larger earthquake. An earthquake of magnitude 5 releases ~32 times more than a magnitude 4. You would require millions of magnitude 3 earthquake to release the same energy as one magnitude ~9. As we know, we don't have that many magnitude 3 earthquakes :P\nSource: Undergrad Geologist",
"It can go either way. If a segment of known fault has very little activity along it, that could indicate it is locked and is accumulating strain that can be released in a rare \"big one\". Alternatively, it could indicate that the strain is being dissipated in very numerous \"microquakes\" that are smoothly releasing it. That's the problem when there aren't detectable quakes along an otherwise fairly active fault system. You don't know if it's building up to something bad, or just sliding along more quietly somehow, below instrument detection. You need to do a lot of other work to survey the regional deformation and how the broader system of faults is behaving. Activity on one fault system that releases strain can also transfer increasing strain to an adjacent fault system, so the history of a whole area factors into it too. Maybe you're locally releasing some strain with that string of 3.0 quakes that is feeding more strain into a different fault further down the line that will then fail in a bigger event.\n\nEven after you've done a detailed survey you're only going to see change in deformation since you started, not necessarily what has already built up before you did the survey. A small time sample is tough to work with for large earthquakes because these are by definition rare events. This is where other information such as paleoseismicity studies can get an idea of how a fault system behaves over longer periods of time (centuries). Then you can try to fit the recent behaviour with the long-term historical pattern. Even if you can't predict an individual earthquake, you'll be able to identify which fault segments are most active and get some idea of the likely severity and frequency. Then you can offer people that \"long-term\" forecast, and they can prepare.\n\nYou should think about earthquakes from the perspective of preparing for \"climate\" (long-term), which geologists *can* give you, instead of the \"daily weather\" (individual earthquakes), which we can't predict. We can't tell you if that fault is going to let go tomorrow, but we can probably tell you what the odds are in the next 50 years, and what magnitude of ground acceleration to expect. That's enough for an engineer or physicist like yourself to work out the forces that would act on a structure, and build appropriately so that people don't get hurt. Train people how to react, build, and prepare as if an earthquake is going to happen tomorrow, then you'll be ready when it does.\n\nNotice I didn't say \"if\". If you're living in an earthquake-prone area like California, it's going to happen someday, maybe tomorrow. Failing to prepare would be kind of like, oh, I don't know, living on the Mississippi floodplain and not preparing for a flood, or living on the coast of Florida and not preparing for a hurricane. \"100-year\" hurricanes, floods, and quakes may be rare, but they do happen.\n\nThe risks vary a lot across California (by orders of magnitude), though, so in some places the risk may not be worth worrying much about. So, find some quake risk maps and figure out your comfort zone. There is [scads](_URL_0_) of information available on the net from your state and federal government, and probably municipal stuff too. Most countries have assessments like this to establish building codes. California's is particularly detailed for obvious reasons. Your tax dollars at work for a good cause: public safety."
]
}
|
[] |
[] |
[
[],
[],
[],
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"http://www.conservation.ca.gov/cgs/rghm/psha/Pages/index.aspx"
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|
1ql4gx
|
i know i don't drink enough water. if you're supposed to drink 6-8 glasses a day, why am i not dead or severely ill?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1ql4gx/eli5i_know_i_dont_drink_enough_water_if_youre/
|
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"Simple, everything you drink currently has water in it!",
"8 glasses a day is a myth. You need as much water as you need. If you live in a cold climate you'd need less. If you lived in a desert just having 8 a day would kill you from dehydration. ",
"Your also supposed to eat a shit ton if servings of fruits and vegetables, most people don't do that either, and they are putting along just fine. ",
"You do **not** want to get kidney stones!\n\n"
]
}
|
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316m8r
|
If black holes have infinite gravity, how come the entire universe isn't a singularity?
|
As far as I know, infinity cannot be added to or subtracted from, so if a black hole has infinite gravity, wouldn't it exert the same pull on the entire universe, no matter how far away it is, thus pulling the entire universe into itself?
|
askscience
|
http://www.reddit.com/r/askscience/comments/316m8r/if_black_holes_have_infinite_gravity_how_come_the/
|
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"text": [
"First of all, in general relativity you have to be careful about what you call \"gravity.\" Here I'll define gravity to be the acceleration required to remain at a fixed distance from the black hole. \n\nA black hole doesn't have infinite gravity except right at the event horizon, where it would take an infinite acceleration to escape or even just to stay in one spot. Everywhere outside that region experiences finite gravity due to the black hole. In fact, if the sun were the same mass but condensed into a black hole, the gravity experienced on the Earth from the Sun would completely unchanged.",
"Black holes don't have infinite gravity. If the sun were to collapse and turn into a black hole today, it would be dark and cold, but we would continue in exactly the same orbit that we have today. Black holes' scary gravitational effect come about because you can get so close to the center of mass of a very massive object. When you are a long way from a black hole, gravitationally it is indistinguishable from an equal mass star.",
"There is no infinite gravity at the event horizon, and you do not need infinite acceleration to escape outside an event horizon... \n\nImagine the earth shrunk down to the size of the pointy tip of a needle. if you're standing at the same distance from the center that you are at now, the force on you would be about the same. Objects in earth's orbit would be at the same distance, etc.\n\nBut, there is no surface for you to stand on, so unless you're orbiting you'll start to fall in. \n\nSince gravity decreases as a square of the distance between you and the source of the gravity, at fairly large distances the pull between your feet and your head is about the same, but as you get closer to the black hole this difference starts to matter. In fact at some point it will be so large it will ip you apart. This works on very small objects too, if you get close enough even atoms can't maintain their integrity. \n\nThe event horizon is something else: in order to escape from a black hole you need to expend a certain amount of energy to counter the force pulling you in. This is known as escape velocity. At the event horizon, the escape velocity is equal to the speed of light, and since it's impossible for anything to travel faster than the speed of light, it is said that anything that goes into the event horizon can never escape. \n\nBut to the thing falling in nothing special happens at the event horizon, there is no barrier there. \n\nThere's something else called the photon sphere, which is the distance at which a stable orbit requires an orbital velocity of C.\n\nBut you, or pieces of you, will continue falling in, and since the black hole itself is a singularity, the 'surface' of a black hole's gravity is essentially infinite, but is so in an infinitely small space. It's a mathematical limit scale problem essentially. Gravity is infinite in an infinitely small space, and finite anywhere outside this space. Tidal forces up this in close are theorized to so strong that weird and wonderful things happen with space itself, but because we can never retrieve information from inside an event horizon this is all theoretical.\n\nNow then: Time dilation. Something interesting happens at the event horizon: since gravity is said to be the same as velocity, and at the event horizon gravity starts to exceed C, we have an interesting situation here: a place in space where the rules of physics seem to break. Time dilation inside a black hole resolves some of the paradoxes, and there is literally a case of because events inside a black hole can't be observed then physics remains sound (remeber the rules are *to a fixed observer* the maximum velocity is C, and *to a moving observer* the maximum velocity is still C, per your viewpoint. Lots of tasty physics here about relative event horizons and why they are undetectable to someone going through it since your reference frame for C keep increasing exponentially as you approach...) Time dilation means that for any object inside the event horizon, infinite time passes for an observer outside its influence. \n\nSo, why isn't the entire universe being sucked in? Gravitational time dilation is the key. Objects being pulled into a black hole reach infinite time dilation at about the event horizon. to people outside the black hole's gravitational influence, nothing ever falls in."
]
}
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3lprbb
|
how can cars with snorkels and on-hood air intakes not have issues running in the rain?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3lprbb/eli5_how_can_cars_with_snorkels_and_onhood_air/
|
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"text": [
"There should still be an air filter between the intake and the engine itself that will screen out most of the moisture."
]
}
|
[] |
[] |
[
[]
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|
1wnsza
|
if the american culture is so old and has changed so much? why cant we say that we are 100% american, instead of 40% irish etc.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1wnsza/eli5_if_the_american_culture_is_so_old_and_has/
|
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"text": [
"Well it's really not that old. What Americans consider old is like a few hundred years, compared to much much longer for other countries.",
"America is not that old. It was made by immigrants from all over the world, mostly Europe. You can say you are 100% American, but you can also trace your ancestry back to other countries that were around for a thousand years before America ever existed as a country.",
"What's American culture? The culture of the United States? Which one? Navajo culture is a hell of a lot older than, say, Irish-American culture, so what are we talking about? Do these questions start to answer yours?",
"You might not realize it, but this is a deeply political question. National identity is a very difficult idea to pin down completely, but simply, it is a personal sense of the cultural group (or groups) a person belongs to. How national identities are formed, overcome, interact, and shift over time all influences the sense of identity people have.\n\nThe United Kingdom is an interesting example of different national identities interacting in distinctly different ways. The core of the UK is made of four countries each with a national identity, England, Wales, Scottland, and Northern Ireland. People who are part of these different nations can also be part of a national identity associated with the UK (which I will call \"British\"). For its entire history, the English have been politically dominant in the UK and they have repeatedly pushed to suppress local national identity and encourage an English-nation-centric British nationality. While many gains were made toward this goal, some national groups in the UK, particularly among the Scottish, have rejected a full move to British nationalism and made efforts to support local national identity either separate or in parallel. A nationalistic Scott is likely to identify primarily as Scottish, but also as British and may choose to serve in the UK armed forces with a sense of nationalistic duty.\n\nIn the USA, things are complicated in different sorts of ways. While several centuries of European occupation has resulted in some national identities (e.g. there is a moderately weak Southern identity), a particularly high and relatively constant influx of immigrants has continually forced national identities to re-form, making very few of them entrenched. These immigrant groups would often seek refuge in nationalistic communities where a link to previous national identity was maintained. Additionally, increased political recognition of pre-European nations (after a significant amount of cultural repression) have established some fundamental ideas about what it means to be 'native' to the place where one lives.\n\n'American' nationalism is also rather large, generic, and difficult to pin-down compared to other national identities. Americans are eager to have something which feels a bit more personal and has a few more definite cultural elements to identify with. Many will seek out a second national identity simply to fill in the gaps which the American identity tends to leave, particularly in the realm of traditional responses to life events. Some people want to identify as their image of 'Irish' because they have images of friends drinking and singing together or some other potentially appealing cliche."
]
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9j4rio
|
why are the symptoms of period pain/ dysmenorrhea so varied?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9j4rio/eli5_why_are_the_symptoms_of_period_pain/
|
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"text": [
"Every body reacts differently to the level of hormones. Prior to starting birth control my periods were ‘normal’ regular cramping not a terribly heavy. I had friends who would double over in pain and miss school. \n\nFibroids and ovarian cysts also make period pains worse. "
]
}
|
[] |
[] |
[
[]
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||
8xvppw
|
What are the main differences between Soviet, Chinese, Yugoslavian, and Albanian communism?
|
[deleted]
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/8xvppw/what_are_the_main_differences_between_soviet/
|
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"_URL_1_\n\n\n\nThis is a great post discussing the differences between the different communist ideologies but don't really talk about yugoslavia or albania (other than a passing reference but doesn't talk about it)\n\n\n_URL_2_\n\nThis thread is specifically on how the communist government of yugoslavia functioned amd what it did\n\n\n\n_URL_0_\n\nThis thread doesn't really talk about how the communists in albania functioned bur does talk about the events and causes leading up to the election of the socialist party\n\n\nUnfortunately, I couldn't find anything talking about how communism in albania differed or functioned",
"Missed the rest of what you wrote outside the title after I made my post so I might as well make a new reply rather than edit it\n\n\n_URL_0_\n\nThe second answer is more relevant to your question as it explains why the government in cambodia became what it was IMO\n\n\n\n\n"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/7mnu6c/what_exactly_happened_in_albania_in_1997/?st=jjgnv9mg&sh=a5f5ae21",
"https://www.reddit.com/r/AskHistorians/comments/64r043/i_know_marxism_leninism_and_maoism_but_theres/?st=jjgnihv6&sh=aa40c35f",
"https://www.reddit.com/r/AskHistorians/comments/67mr10/what_was_titos_yugoslavia_like/?st=jjgnsd5d&sh=b03254bf"
],
[
"https://www.reddit.com/r/AskHistorians/comments/3pwta9/can_someone_explain_what_was_going_on_in_khmer/?st=jjgoc7ti&sh=4f502fc1"
]
] |
|
ryy3d
|
How does the charge of a particle actually work?
|
I understand everything about the fact that opposites attract, polarities, magnetic fields yada yada. But what exactly IS the magnetic field? Its something that we cannot see or feel without something else that ALSO creates a magnetic field. But how does it work?
|
askscience
|
http://www.reddit.com/r/askscience/comments/ryy3d/how_does_the_charge_of_a_particle_actually_work/
|
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"text": [
"I'm not clear on your question. It sounds like you're asking \"why do opposite charge repel one another while like charges attract?\" If that is indeed your question, I have to direct you to Feynman's [beautiful answer](_URL_0_) to that very question.\n\nAlso, you should be aware that charged particles generically generate *electric* fields, not a magnetic fields. You get magnetic fields when a charged particle is moving."
]
}
|
[] |
[] |
[
[
"https://www.youtube.com/watch?v=MO0r930Sn_8"
]
] |
|
dlig1p
|
do sociopathic people still have a psychological need to interact with other human beings to not go insane?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/dlig1p/eli5_do_sociopathic_people_still_have_a/
|
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"Every patient have different profiles of their behaviours. Isolation cells in general have very little to no positive effects on sociopathic people (though please bear in mind that sociopath is an informal term to use) because humans are social animals and restricting one's ability to communicate likely only manifests someone's condition.\n\nAnti-social behaviours don't make people go insane unless environmental factors which cause them to develop other disorders like psychosis which further alter their mental state.",
"Most human beings can function without other human beings for long periods of time. Their happiness is likely to be negatively affected, but to my knowledge solitude isn't otherwise harmful.\n\nHarmful effects are separate from merely being isolated. Solitary confinement in prison is very stressful. And when stuck in space/underwater/extreme weather for a long time there is a large risk of cabin fever. These aren't really caused by the absence of people (though human contact might make the situation less stressful). Afaik, this is more related to lack of outside stimulus, monotony, claustrophobia and getting stuck in a destructive mental routine. Whether this is worse or better for sociopaths, I don't know.\n\nEdit: added claustrophobia."
]
}
|
[] |
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[
[],
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3cqa92
|
why is there a need for a 7nm chip manufacturing process?
|
Due to the achievements of IBM in making a 7nm process chip, I have a question:
Why do we get better performance out of a smaller chip and what do the 7nm referr to?
I mean it is nice to get a smaller sized chip, but why can't we just make a bigger CPU with more transistors and more performance?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3cqa92/eli5why_is_there_a_need_for_a_7nm_chip/
|
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"Smaller chips have a lot of advantages. First of all, they are cheaper to make. More fit on a wafer and generally you get higher yields. Second is power consumption. Smaller chips waste less power (due to things like parasitic capacitance), so they produce less heat and can be used with less elaborate cooling. Finally we have so many handheld devices today, we need the actual chip to be physically small to fit in the devices.\n\n7nm basically refers to the minimum feature size. Basically it is the smallest thing that can be made on that process.",
"more material - > more resistance - > more losses - > more heat\n\n\nThat leaves you with 2 very big problems: heat and power. And making things smaller would solve both of your problems. Your chips will be more effective use less energy and therefore cause less heat. Or you could make them bigger pump in more power and figure out some awesome way to cool things down again, which in turn takes even more energy to do. In addition to that those cooling solutions tend to be noisy big and have many moving parts that are hard to make. And at some point it will be almost impossible to cool down a chip. \n\n\nAnd this isn't a small problem, just search for power density and you'll find that a cpu gets closer and closer to the power density of a nuclear reactor. And you wouldn't want try to cool those down with tiny fans. Those little chips might not look like much but the only difference between them and a electric heater is size (and of course one of them can be used for calculations and stuff). \n\nEdit: And it is probably worth mentioning that those chips stop doing calculations and stuff when they start melting themselves"
]
}
|
[] |
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[
[],
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|
1hrvn5
|
why some people freckle whilst others tan.
|
That's it really. I know what causes freckles, but what causes some people to freckle instead of getting an even tan like most people?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1hrvn5/eli5_why_some_people_freckle_whilst_others_tan/
|
{
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2
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"text": [
" Melanin is what makes skin darker. Freckles produce more melanin when exposed to sunlight. So, if you have freckles, they get darker when exposed to sunlight. It's not that the sun is creating freckles, it just makes the freckles darker. You may not have noticed them before because they were too light, but once exposed to sun they get darker and more apparent. ",
"People with freckles have blotches of melanin; darker skinned people and those who tan evenly have even patches of melanin. \n\nI wish I could smear my freckles out and have an evenly beige body. That would be fantastic."
]
}
|
[] |
[] |
[
[],
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|
4zxga0
|
why is the inside of my microwave always several degrees warmer than the ambient room temperature?
|
It's always noticeably warmer inside my microwave - the difference can be felt when I reach in to put something on the turntable. I found something somewhere that said this happens in in over-the-range microwaves, but I don't recall seeing an explanation as to why. I'll be grateful to anyone who can explain this one to me!
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4zxga0/eli5_why_is_the_inside_of_my_microwave_always/
|
{
"a_id": [
"d6zik7l"
],
"score": [
2
],
"text": [
"You most likely have a vent fan that goes to outside. It is usually only sealed with two flaps that only open outward. Those let a bit of outside air leak back in. Attic/wall heat from where the vent tube travels may also contribute."
]
}
|
[] |
[] |
[
[]
] |
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3iklm4
|
if moving at the speed of light causes you to experience no time, why does light still take time to get places?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3iklm4/eli5_if_moving_at_the_speed_of_light_causes_you/
|
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"text": [
"I think the reason for your confusion is a misconception of special relativity. \n\nYou often hear people say something along the lines of *if you travel at speeds close to the speed of light, time gets really slow for your.* \n\nUnfortunately, that is very wrong. What special relativity actually says is:\n\n*If an object is moving at high speeds* **relative to you** *you will see its time going slower than yours. Your time, on the other hand always passes at the same rate, since you are always at rest in your own frame of reference.*\n\nTo illustrate this: you are moving at 99.99% of the speed of light right now relative to cosmic muons. Does time slow down for you because of that? \n\n***\n\nOther posters have mentioned, that light allegedly \"experiences no time, since it is going at c\". That is false as well, so I just wanna address this issue quickly:\n\nIt makes zero sense to state that a photon does or does not experience time. In order to make a meaningful statement about the experience of an observer, we have to be able to assume this observer's rest frame. Otherwise, relativistic effects will distort our conclusions.\n\nHere is the thing though: photons do not have a rest frame. They move at c relative to all frames of reference. \nThus, we can never make a meaningful statement about \"the experience of photons\".\n\nTo illustrate, why this is a fundamental problem, that cannot be solved by taking the limit as v approaches c, let's consider the following:\n\n\nTime always passes at the same rate for you, no matter how fast you are moving relative to an inertial frame of reference, since you are always at rest in your own frame of reference. Clocks that are moving *relative to you* are going slower. Thus, no matter how fast you are moving relative to an inertial frame of reference, for *you* time passes normally. \nThe same would be true for photons, if the limit of v - > c were an appropriate approximation, since they still rest in their own frames of reference as their rest mass approaches 0. \nSo, according to this, photons would have to experience time normally, wouldn't they? \nBut they move at c relative to **all** frames of reference, so there cannot be a frame in which they do not move at v - > c. Which means their clocks have to slow down to a rate where time stops passing.\n\nThose two statements are mutually exclusive, which means it is impossible to make a valid statement about the rate at which time passes for mass-less particles. \n"
]
}
|
[] |
[] |
[
[]
] |
||
h6mhl
|
An average sized man, a body builder and a morbidly obese man are all deprived of food. Who would starve to death first and why?
|
Pretty straightforward. All the same height, the only variable would be their weight/body mass. Also, no funny stuff is going on, like they're not locked up together so no one can eat each other. I just had a dream about this, now I gotta know.
**EDIT** They are not deprived of water. Sorry about that.
**EDIT part deux** For the sake of this illustration, all 3 men are 6 feet tall.
The "average sized" man might weigh close to 170 lbs/77 kg.
The body builder and obese man each represent extremes on their respective end of the spectrum (imagine Ronnie Coleman and [this guy](_URL_0_) )
|
askscience
|
http://www.reddit.com/r/askscience/comments/h6mhl/an_average_sized_man_a_body_builder_and_a/
|
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"text": [
"Are they also deprived of water? ",
"I would hypothesize the body builder as fat stores can be useful to sudden loss of a food source,bodybuilders tend to have less fat then the avg person. I would look at large animals that hibernate as an example.",
"Well, I think (just guessing) the bodybuilder would probably die first, because his basal metabolic rate will be far higher and also he would probably have the least amount of body fat that could support him during starvation. I find it harder to guess who will live longer among the average sized man and a morbidly obese one. Its just too complex and I don't think I'm knowledgeable enough..",
"Check out the wikipedia articles on [famine](_URL_0_) and [starvation](_URL_1_). They don't answer the question, but it does have some background info. It does say that women tend to last longer during famine possibly due to the extra body fat.",
"The average sized man would die first. Muscle can be broken down and converted to energy. As long as the muscular guy did not continue to exercise while he was starving, his BMR would rapidly decrease in the absence of any caloric intake. The fat guy would survive the longest, obviously, since fat has a high caloric yield (per gram). \n\nEdit: Cannibalism not allowed. Got all excited for nothing.",
"if by body builder you mean someone who goes for low body fat to pose at muscle head shows, then he'll probably die first. \n\nif by body builder you simply mean someone with a lot of muscle and may have normal amounts of fat as well (think weight lifters) the average sized man would probably die first. \n\nthe morbidly obese guy would definitely die last. \n\nThere's a peer reviewed study (available at _URL_0_) of a morbidly obese man fasting under similar conditions under supervision for nearly a year and losing nearly 300lbs in the process",
"The bodybuilder, then the normal guy, then the obese guy. Because without food you want low metabolism-to-stored-energy ratio and that is lowest in an obese person.",
"Someone could do the maths on it, assuming a body builder to have 65% body water, the average man to have 60% body water, and the obese man to have 50-55% body water. \n\nAssume the body builder to have 5-6% body fat\nassume the normal man to have 13% body fat\nassume the obese person to have 25-30% body fat\n\n9 calories per gram for fat, 4 grams for protein. For this assume none have any muscle glycogen (carbohydrates). \n\nThen make reasonable estimates for their weight. Say if they are all 6 foot. \nThe obese man will have a BMI of 30 therefore approximately 98 kilograms\nThe body builder can weight 80kg\nThe average guy can weigh 75kg (times 2.2 for pounds)\n\nFrom this you could work out (very generalised) total energy content, and assuming they all have the same starvation adjusted metabolism, who would be 'used up' the quickest.\n\nI'm not going to do the maths because i'm going to bed!\n",
"I think it's worth mentioning that lack of [essential amino acids](_URL_5_) (that is amino acids the body can't synthesise on its own), probably would kill you before lack of energy (lack of [ATP](_URL_2_)/[GTP](_URL_4_)). Since amino acids are important for protein generation, and proteins need continues renewal and are what keeps the metabolism in [ship shape condition](_URL_3_).\n\nOh btw, when the body starts on attacking the fat tissue during starvation, it usually runs out of Coenzyme A for [Acetyl-CoA](_URL_7_) production, an improtant intermediate for feeding the energy wheel called the [Citric acid cycle](_URL_0_). When it does that, it cheats and starts on creating [ketone bodies](_URL_6_), which in the blood lowers the pH and might cause [acidosis](_URL_1_). That might kill you. ",
"Keeping in mind that lipids provide about 9kcal/mol and proteins and carbs provide about 4kcal/mol the fat man's energy supply would be over 2 times as valuable as the body builder's. The normal man doesn't have much of a reserve of either and probably would be the first to go.",
"I've thought of something similar before, but instead, who would freeze to death first? Same situation, no food, but the result of death will not be malnutrition but hypothermia. They'll die in a matter of a day or two, who dies first? Does the fat guy's insulation benefit him more than the efficiency of the athletic guy?",
"Annecdotal I know, but I recall reading in Antony Beevor's Stalingrad about German soldier trapped in an encirclement without re-supply (when Hitler basically let his army starve to death) and he stated that bigger stronger soldier were the first to drop and smaller guys survived, in general.",
"The body builder first, then the man and finally the obese man.",
"Unknown as base metabolism of the three is unknown. After a month of starvation you might venture a guess, because then you know how each bodies emergency program looks like.\n\n",
"\"I'm not fat.... I'm drought and famine resistant.\" - Homer Simpson",
"well, what do bears do before they hibernate? They gorge and make themselves FATTER. So I would have to say that the obese man, if his health is otherwise in decent shape, would survive the longest. "
]
}
|
[] |
[
"http://i.imgur.com/IYWIX.jpg"
] |
[
[],
[],
[],
[
"http://en.wikipedia.org/wiki/Famine",
"http://en.wikipedia.org/wiki/Starvation"
],
[],
[
"nih.gov"
],
[],
[],
[
"http://en.wikipedia.org/wiki/Citric_acid_cycle",
"http://en.wikipedia.org/wiki/Acidosis",
"http://en.wikipedia.org/wiki/Adenosine_triphosphate",
"http://www.expasy.org/cgi-bin/show_thumbnails.pl",
"http://en.wikipedia.org/wiki/Guanosine_triphosphate",
"http://en.wikipedia.org/wiki/Essential_amino_acids",
"http://en.wikipedia.org/wiki/Ketone_bodies",
"http://en.wikipedia.org/wiki/Acetyl_coa"
],
[],
[],
[],
[],
[],
[],
[]
] |
|
22c1gf
|
How did people folding their hands together when praying originate?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/22c1gf/how_did_people_folding_their_hands_together_when/
|
{
"a_id": [
"cgle95r"
],
"score": [
3
],
"text": [
"According to \"The Knight, The Lady And The Priest\" by Georges Duby folding hands together when praying has its origins in the warrior culture of the early middle ages. Lesser nobles used the gesture to signify subordination when they took oaths of fealty to lords of higher rank. They, or rather their siblings who entered the church, then transposed the gesture to the act of prayer, which was, according to their world view anyway, an expression of subordination to the highest lord of all, namely God.\n\n"
]
}
|
[] |
[] |
[
[]
] |
||
3alv8o
|
How did people in Rome (c. 100 CE) work for a living? What jobs did they have?
|
We have really complex employment structures today. Looking at the census tables of where I live (Ontario, Canada) - the more popular industries are: Construction, Manufacturing, Healthcare, and Trade. Some types of jobs transcend industries. Administrative jobs exist in practically every business - from primary schools to hospitals.
I am interested to know what people did for a living in Rome (c. 100 AD). I pick that time and city because it was quite populated with a million people living in it. With so many people, there had to be more jobs, and more complexity in the industries - I imagine.
What did they do? What kind of jobs were there? How did they job structures compared with ours today? For example, majority of modern jobs in North America are service-producing instead of goods-producing. How was the services industry in Rome back then? Today, trade is the most popular service industry. But how did trade work back then in terms of job structure and industry complexity?
Honestly, I have no specific questions because I don't know enough about the topic to ask a specific question. I am hoping the answers in this thread or any book recommendations can enlighten me.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/3alv8o/how_did_people_in_rome_c_100_ce_work_for_a_living/
|
{
"a_id": [
"csdx9i4"
],
"score": [
3
],
"text": [
"Well, just about any job you can think of. It was, as you say, a city of a million people, which requires an enormous amount of labor just to stay operable. You need tavern owners, builders, carpenters, potters, tanners, weavers, as well as sausage sellers, longshoremen, porters and firefighters. I suppose the big difference between a modern city is that there would be a much higher proportion involved in secondary production (basically primary=extraction of resources, secondary=finishing of resources, tertiary=service) because they weren't a post industrial economy.\n\nIt is a bit difficult to say whether there was a primary industry in Rome because Rome did not develop to its size based on comparative advantage in a particular economic sector (like, say, Detroit with cars) but because of the imperial flow of resources."
]
}
|
[] |
[] |
[
[]
] |
|
2cptb4
|
Did Scottish Highlanders really ride a horse without wearing anything under the kilts?
|
This came up between myself and my wife while watching Outlander. She mentioned they never wore anything under their kilt and they rode for days on end sometimes which got me to thinking about the state of their 'manhood' for lack of a better word. I mean, if this is true, wouldn't they be heavily damaged or at the least calloused like concrete?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2cptb4/did_scottish_highlanders_really_ride_a_horse/
|
{
"a_id": [
"cjhw0a0"
],
"score": [
5
],
"text": [
"They wouldn't have worn kilts for riding horseback, they would have worn tartan trews for riding. The idea of riding in a feilidh-mor isn't well supported, and honestly doesn't not seem smart. Common highlanders would not have been able to afford a horse in the 18 and 19th centuries, and the Highland gentry that had been able to afford one would wear tartan trews for riding. Trews would offer protection to the inner leg that a kilt, without anything underneath, cannot provide. Kilts would be impractical. Just remember it's TV. \n\nHow is that show, btw?\n\nI would check out _URL_0_ with Matthew Newsome for more information. He's one of the few kilt historians out there, and his work is top notch."
]
}
|
[] |
[] |
[
[
"albannach.org"
]
] |
|
5yx6we
|
why do some people cry when they eat spicy stuff?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5yx6we/eli5_why_do_some_people_cry_when_they_eat_spicy/
|
{
"a_id": [
"detsae4"
],
"score": [
2
],
"text": [
"They don't cry, they tear up. \n\nYou body thinks that spicy stuff is somehow bad. Maybe it's poisonous, maybe something else, but definitely not something you would need or want. \n\nAnd your body is trying to get rid of it. Easiest way is sweating, tearing up, runny nose or even diarrhea. "
]
}
|
[] |
[] |
[
[]
] |
||
d5idoo
|
What did the Franks refer to themselves collectively as in the decades before and after Charlemagne's rule?
|
Also during the interim between Merovingian and Carolingian rule. I'm genuinely ignorant on this topic.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/d5idoo/what_did_the_franks_refer_to_themselves/
|
{
"a_id": [
"f0m9u4z"
],
"score": [
20
],
"text": [
"Franks identified themselves...well, as Franks or Franci, as their main collective identity. \nThis term is present everywhere in contemporary texts and unmistakably designs the inhabitants of the \"Frankish core\", so to speak, made of the sub-kingdoms of Neustria, Burgondia and Austrasia : not that, critically with the VIIIth century, there weren't regional identities stemming from the association of local aristocracies to sub-royal palaces (the Chronicle of Fredegar being rather Austrasian in its support, the Book of the History of Franks rather Neustrian and loyalist) but never to the point challenging a common Frankish identity in any late Merovingian or early Carolingian source.\n\nPeripheral ensembles such as in Aquitaine (where people considered themselves as Romans), Thurgingia, Bavaria, etc. are a mixed bag : they did had populations creating or re-creating regional identities distinct from Franks, but not to the point they necessarily thought themselves entirely outside the Merovingian world, especially as their own elites were familialy, politically and culturally close to \"core\" Franks. Eudon, who managed to rule Aquitaine as princeps (basically claiming the same kind of power there than a Merovingian king) had a Frankish name and at least acknowledged some Merovingian and early Carolingian over-lordship (compelled and forced in the last case, arguably).\n\nEarly Carolingians replaced most of local aristocracy with their clients or family, increasing the Frankish character of Aquitaine, Provence, Alemania, Thuringia and Bavaria (arguably being less prone to do so in Saxony and Italy, to attempt reaching a compromise with locals). \nWhen Charlemagne plan in 806 the split of his empire between a Francia auditioned of most of Germania, an Aquitaine additioned from Burgundy, and an Italy additioned from Bavaria; he doesn't consider giving \"ethnic\" kingdoms to his sons, but \"territorial\" kingdoms, that would remain Frankish while dominating distinct peoples and gives them authority over Frankish nobles and territories as well; just as he's King of Franks and Lombards. \nWhen Peppin II revolts against Louis I's decision to confiscate his kingship and gives it to Charles, he doesn't lead a national revolt, but a Frankish nobiliar revolt over a territorial (and particularist, truth to be told) sub-kingdom.\n\nThe situation arguably changed with the split of Carolingia into de facto distinct kingdoms (whereas Merovingian splits didn't implied the utter division of the regnum), but as every Carolingian king was Frankish, in a first time nobody really knew how to name the inhabitants of their kingdoms : Charles was reputed ruling over the \"Carlensenses\", the people of Charles' kingdom; and of course the \"Lotharingia\" of Lothar II. \nDuring the IXth century, however, territorial and ethnic identities appeared in royal titulature : several western Frankish kings were named \"King of Franks and Aquitains\" up to the XIth century, Charles the Simple was acknowledged in 898 as \"King of Franks, and Aquitains and Goths\", (meaning the region between Rhone and Ebre), and Raoul \"King of Franks, Burgundians and Aquitains\". \nLate Carolingian official titles being generally non-descript, \"king\" or \"august emperor\", previously mentioned titles are more given than assumed, but *rex francorum* dominates almost systematically when territories and \"nations\" are mentioned) \nIt is less an evidence of distinct and competing identities, than competition over territories becoming more and more independent (and where the temptation of a separate *regnum* as in Provence, is quite present) and an affirmation of royal legitimacy over them (either due to sheer claim, either due to a local support base)\n\nWhile the Frankish identity lost ground in Germania (except in Franconia), it is less an ethnic revival, than a new political aspect of the situation as \"national\" dynasties emerge. On the other hand, western Francia kept a whole Frankish identity over regional and political ones (to quote Gavaudan, \"Angevins, Bretons, Cambresis, Provencals, Poitevins\" etc.) that would evolve trough the significant political, social and cultural change of the high middle-ages and became \"French\"."
]
}
|
[] |
[] |
[
[]
] |
|
65865f
|
why do humans get nervous in non life-or-death situations?
|
I completely understand why we'd be nervous when facing a predator, or while hunting, exploring, etc - this fits into our backstory very well. But why do everyday situations cause this emotional/hormonal reaction if they aren't going to actually physically impact us in any way?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/65865f/eli5_why_do_humans_get_nervous_in_non_lifeordeath/
|
{
"a_id": [
"dg87pji"
],
"score": [
3
],
"text": [
"The situation is still stressful, so the body will react as if it is in true danger. The body itself doesn't know that you're about to take a test or ask a girl out. It just knows there is something that is causing you stress, so whatever we, as higher thinking mammals, view as stressful, the body will react to."
]
}
|
[] |
[] |
[
[]
] |
|
1wld7u
|
If it wasn't for World War II, would the Wall Street Crash of 1929 and its economic repercussions have lasted longer?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1wld7u/if_it_wasnt_for_world_war_ii_would_the_wall/
|
{
"a_id": [
"cf32e11",
"cf36dvw"
],
"score": [
5,
9
],
"text": [
"Actually when you look at economic growth from 41 to 45, it hardly changed, and in fact the depression remained really until 48. Wars don't create wealth, they destroy wealth. This is the broken window fallacy. \n\n[heres a Forbes article about it](_URL_0_)",
"As it is, this question is better suited for /r/HistoricalWhatIf. A better way to pose this question is, \"How did WWII affect the Great Depression?\""
]
}
|
[] |
[] |
[
[
"http://www.forbes.com/sites/peterferrara/2013/11/30/the-great-depression-was-ended-by-the-end-of-world-war-ii-not-the-start-of-it/"
],
[]
] |
||
1kqwbw
|
A question about micro black holes and Hawking radiation.
|
How is a micro black hole ( < 1 yoctometer) able to absorb particles that are larger than it's diameter?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1kqwbw/a_question_about_micro_black_holes_and_hawking/
|
{
"a_id": [
"cbrozls",
"cbrp0o3"
],
"score": [
5,
20
],
"text": [
"Neither particles nor black holes have a diameter. They have cross sections, or areas where probability of interaction is non-zero. This is what is meant when someone talks about the diameter of a particle.",
"Particles don't really have a diameter. Instead, they have a *wavelength.* The wavelength of a particle is a function of its energy, and it can be thought of as a sort of minimum bound on localizing that particle. You can't ever say that a particle with wavelength X is localized to a region Y, if Y is smaller than X.\n\nThis comes up in the study of black hole thermodynamics. What is the *smallest amount of energy* a black hole can gain? It's the energy of a photon with wavelength equal to the diameter of the black hole. If the photon has a wavelength longer than that, it won't interact with the black hole at all. (For more on this, if you're interested, consult the work of Jacob Bekenstein.\n\nThe other thing to remember is that very small black holes — if they exist at all, which is not at all clear — would vanish almost immediately in a burst of Hawking radiation. The temperature of a black hole is *inversely* proportional to its surface area. The bigger the black hole, the colder it is. A very small black hole would have a truly astronomical temperature, and would very quickly radiate all its energy away as blackbody radiation."
]
}
|
[] |
[] |
[
[],
[]
] |
|
ggd9r
|
Is there any known way to bend space the opposite way of gravity and create anti-gravity?
|
askscience
|
http://www.reddit.com/r/askscience/comments/ggd9r/is_there_any_known_way_to_bend_space_the_opposite/
|
{
"a_id": [
"c1ncbvt"
],
"score": [
7
],
"text": [
"It would require some sort of negative energy distribution, just as a positive energy distribution warps space and creates gravitational effects.\n\nSuch a source of negative energy has not been discovered. Sorry!"
]
}
|
[] |
[] |
[
[]
] |
||
22agyz
|
Why did the civil rights movement of 1865-1876 collapse? We got the 14th Amendment out of it but it was ignored...what went wrong?
|
I've read the book "The Bill Of Rights: Creation to Reconstruction" by Akhil Reed Amar that covers the drafting of the 14th Amendment, what John Bingham was trying to do and the reaction of the courts in cases like Slaughter-House and US v. Cruikshank. I intend to read "The Day Freedom Died" by Charles Lane on the events at Colfax LA and the Cruikshank case that came out of it.
I guess the answer is really "we were still a bunch of racist fucks" but...I think there's lessons here to be learned about an entire civil rights movement that failed hard...
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/22agyz/why_did_the_civil_rights_movement_of_18651876/
|
{
"a_id": [
"cgkxhp0"
],
"score": [
23
],
"text": [
"I honestly believe that it was much more war fatigue then anything else. Lincoln was followed by Andrew Johnson, a Democrat. Johnson, in my opinion, did more to harm civil rights in the United States then any individual in our history. As president he ordered the southern states to reform their governments, returned confederates to power(who Johnson had pardoned), and allowed the reconstituted governments to pass black codes, which basically returned the vast majority of negro's into a position similar to their pre-war state. He also opposed the 14th amendment, and worked hard to remove Lincon's loyalists, which ultimately resulted in impeachment. \n\nJohnson was succeeded by Grant. Grant supported radical reconstruction, and began to rollback Johnson's changes. This led to a high level of violence, mob lynchings and assassinations. In a very real sense, it was similar to what we see in parts of the middle east with modern sectarian violence. Black voters came out in force, and African-American's who elected to all levels of government. Northern opportunists came down to the south, and rightly or wrongly, where identified as corrupt \"carpet baggers\". \n\nGrant's presidency is marred by massive corruption, and the first major depression that occurred in 1873 caused the administration to lose support in America. \n\nThe KKK, which was to the Democratic party as the IRA was to Sinn Fein, continues to escalate violence, including killing Republican and African-American lawmakers in the south while the northern states increasingly wanted to disengage from the \"southern problem\", no matter what the outcome for African Americans would be. Democrats returned to control the house in 1874, ending legislative initiatives to protect Negros, and continue reconstruction. Two horrible US Supreme Court cases further restricted the federal government's ability to protect citizens. \n\nFinally in one of the most corrupt deals ever - the Republican and Democratic candidates in 1876 deadlocked in the electoral college. The Democrats gave the Republicans the presidency in exchange for ending reconstruction, locking in Jim Crow for another hundred years.\n\ntl;dr\nThe KKK, which was the military wing of the southern democratic forces, unleashed a decade of violence, while Republican forces collapsed to corruption and depression. The bad guys won. \n"
]
}
|
[] |
[] |
[
[]
] |
|
hm42e
|
What exactly causes the media to find out about certain science discoveries (and then to turn them into headlines)?
|
Like this story? _URL_0_
I'm especially interested, since the type of work I'm doing over the summer and next year is the type of work that does tend to grab media headlines. But at the same time, I know that the media tends to misrepresent people's work (as it had did with one guy who was working in the lab I'll work in next year) - and if this type of thing ever happens with me, I certainly don't want the media to misrepresent what I did.
|
askscience
|
http://www.reddit.com/r/askscience/comments/hm42e/what_exactly_causes_the_media_to_find_out_about/
|
{
"a_id": [
"c1wh6ci"
],
"score": [
3
],
"text": [
"Each university has a PR department whose job is to keep on the lookout for interesting publications or discoveries made by people working there and send out press releases to the media. In that article you linked it refers to this as \"...a Monash release said Monday.\"\n\nThe idea is that the more the university is in the news for making discoveries, the higher their prestige, but it's usually something that individual departments don't have time and energy to take care of, so there is a specific department whose job is to represent the school as a whole, all disciplines. Many times when you see a story like this on the web, the original source is hosted on some non-specific page on the university's site, i.e. it's from a generic \"latest news\" section and not from the specific lab's page or from the professor's personal page. That's the PR department at work. For example, take that recent story about 'chameleon magnets'. You'll see it posted on sites like _URL_3_ ([like so](_URL_2_)) but you notice at the bottom the source is \"Provided by University at Buffalo\", and if you google you see that the [original source of the article is here](_URL_1_) at the generic 'UB News Center', not [the Physics department](_URL_0_).\n\nSo as you can see the first step in the process and the place where misconceptions or misrepresentations are most likely to emanate is the PR department. If you want to make sure that your work is not misrepresented, make sure you figure out who this is at your organization and see if you can get advance notice before they issue PR statements or news reports regarding work in your lab."
]
}
|
[] |
[
"http://www.upi.com/Science_News/2011/05/24/Student-finds-universes-missing-mass/UPI-36851306283405/"
] |
[
[
"http://www.physics.buffalo.edu/faculty/IZutic.html",
"http://www.buffalo.edu/news/12608",
"http://www.physorg.com/news/2011-05-chameleon-magnets-ability-revolutionize.html",
"physorg.com"
]
] |
|
48i188
|
Can a tidally locked planet still rotate on an axis if its pole is pointed at its star?
|
askscience
|
https://www.reddit.com/r/askscience/comments/48i188/can_a_tidally_locked_planet_still_rotate_on_an/
|
{
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"d0jronu"
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"text": [
"Hm, the poles of astronomical bodies are where the axis of rotation meets their surface. For an object to be tidally locked to another, its axis of rotation must be perpendicular to its orbital plane... so the pole of a planet tidally locked to a star cannot be pointed at the star. \n\nIn other words, if you draw the orbit on a piece of paper as a circle, the axis of rotation of the planet must be pointing out of the paper, otherwise the planet won't be able to rotate so that the same face always faces the star."
]
}
|
[] |
[] |
[
[]
] |
||
1n91o9
|
How effective were the Eastern European Axis powers in WW2?
|
Like Bulgaria, Hungary, Romania, etc. Did they fight effectively or were they just along for the ride with Germany doing all the work?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1n91o9/how_effective_were_the_eastern_european_axis/
|
{
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"ccgh6sd",
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],
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],
"text": [
"Romania suffered the largest casualties in the war on the Axis side after Germany on the Eastern Front. The \"auxiliary\" Axis soldiers, to put it in a manner of speaking, were poorer soldiers than the Germans. The only ones that didn't get (too much) grief from the German officer corp were the Finns and the Cossacks/Old Whites. The Finns mostly because their section of the front was almost exclusively Finnish manned and the Cossacks/Old Whites due to their fervour in fighting against the Soviets.\n\nEDIT: forgot to specify the location of the Romanian casualties.",
"Stating that \"the Germans did all the work\" is a huge overstatement, but depending on how you look onto it, it can hold some truth.\n\nIn the Operation Uranus (battle of Stalingrad was a result of it) the German 6th Army was encircled after an attack on 3rd and 4th Romanian Armies. Hungarian 2nd Army was also almost destroyes in that, and the following operations. \n\nYou can find sources that say that the German commanders did not hold their allies in high regard, but on the other hand, you should consider the equipment of the Axis allies. They were given tasks not as important, and failed to do them, but they had very little armoured equipment and were fighting a war against the Soviets (which had almost infinite manpower and motivation) in the Soviet's homeland. \n\nIn my opinion, Slovaks, Italians, Romanians, Bulgarians, Hungarians, were sent there to die, so the Germans could die in a more important battle. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
ixcbk
|
Why have vaccines been so successful?
|
Simple question, I think for the experts here. I just want to know what it is about vaccines that have made them so effective against fighting ailments such as Polio? I have tried to search the subreddit and google for a similar question but have not found an answer, also my google-fu may be weak or that filter-bubble may be blocking me.
|
askscience
|
http://www.reddit.com/r/askscience/comments/ixcbk/why_have_vaccines_been_so_successful/
|
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"Basically, if you expose someone to a disease (or a closely related disease), then their body will build a tolerance to it. \n\nYou know how as a kid you got chicken pox, which went away quickly and now you're immune to it? It works through the same principles.",
"Training the cops to recognize the baddies by throwing half-dead baddies at them :)",
"Vaccines are generally dead or weakened contagions whose purpose is to \"prime\" your body to fight the full-fledged infection. Often you can still become sick with whatever you've been vaccinated against, but your immune system can fight it off quicker and more effectively.\n\nPolio is a good example of a viral disease whose vaccine inhibits the crippling effects and the transmission characteristics, so if you give enough people the vaccine then you build up a \"herd immunity\" in the community. Those that aren't vaccinated are still protected since the chance of them coming into contact with someone who carries the virus is lessened. If you're pro-active enough in vaccinating every person you possibly can, eventually the virus dies out in the population and is effectively eradicated.",
"Fun fact - humans have succeeded in eradicating two diseases through widespread vaccine use. The first is smallpox. The other is rinderpest, a disease that kills cows and bison."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
a40qqd
|
When did we know that birds are descended from dinosaurs?
|
I remember back in school, some 25 years ago, that I was taught that *maybe* birds and dinosaurs were related but that there was no real evidence.
Did paleontologists (or whoever knows these things) not know back then, or was my teacher's information just outdated?
|
askscience
|
https://www.reddit.com/r/askscience/comments/a40qqd/when_did_we_know_that_birds_are_descended_from/
|
{
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"The idea was proposed back in the 1860s. It was the 1970s however before it started to become accepted in the scientific community and the evidence from fossils was available to really prove it. It would be the mid 80s before the deal was sealed by cladistics: Gauthier, Jacques. (1986). \"Saurischian monophyly and the origin of birds\". For all those dates add in 1-10 years for it to filter down to teachers and text books depending on how much an individual teacher paid attention to the latest developments in paleontology. ",
"Almost as soon as the first *Archaeopteryx* was formally described by Richard Owen, other scientists noticed the many similarities between this \"first bird\" and certain dinosaurs. Within 5 years—so, 1868—you had Thomas Huxley loudly banging the \"birds and dinosaurs are related\" drum, as well as Cope and a few others. When the 1870 \"Berlin *Archaeopteryx*\" revealed its dinosaur-like teeth, the comparisons to *Compsognathus* were hard to miss. Owen himself never liked the idea, but a lot of contemporary biologists did. It was a fairly popular, but not *universal*, hypothesis within biology.\n\nBut in the 1920s, a Dane by the name of Gerhard Heilmann argued—quite persuasively at the time—that birds could *not* have evolved from dinosaurs. Dinosaurs, you see, had at some point in their evolutionary history lost their collarbones (clavicles). Birds *have* clavicles (fused together into a single \"wishbone\") and it was a popular idea in the '20s that once a trait was lost it could not be re-evolved. So birds must have branched off the reptile line before dinosaurs did. Heilmann put birds as descendants of the \"thecodonts\", a (now-obsolete) group containing the crocodile-like ancestors of dinosaurs, pterosaurs, and modern alligators and crocodiles. Heilmann's position was attractive enough that the \"birds are dinosaurs\" idea was effectively put to rest, and for the next several decades the textbook answer was \"birds are some kind of thecodonts, but not *dinosaur*\\-thecodonts.\"\n\nIt was *Deinonychus*, discovered in 1964 and described formally in 1969, that started pulling scientists back into the \"birds are dinosaurs\" way of thinking. Ostrom spent several more years after *Deinonychus* comparing *Deinonychus* and *Archaeopteryx*, arguing that their skeletal similiarities couldn't be the result of simple \"convergent evolution\". (Alan Grant in *Jurassic Park* mentions this specific argument of Ostrom's: \"And look at the half-moon shaped bones in the wrist. No wonder these guys learned how to fly.\")\n\nThis was still just one hypothesis, however; there were still a lot of \"birds are thecodonts\" advocates, and there was a competing hypothesis that, based on skull features, birds were *crocodylomorphs*. All three arguments were swirling around paleontological circles.\n\nIn 1986, Gauthier published his cladistic comparison of birds and dinosaurs, and showed that—by sheer number of shared anatomical traits—birds pretty much *had* to be some kind of theropod dinosaur. Birds weren't \"thecodonts\", they weren't crocodylomorphs, they were *definitely* dinosaurs. If your teacher was telling you 25 years ago that there was \"no real evidence\" that birds were dinosaurs, they were giving you out-of-date information.\n\nOf course, there was also no Internet 25 years ago, so although your teacher was at least a decade behind, not having access to the most current information was a little more understandable than it would be today.\n\nThe final clincher for any holdouts (absent a handful of ~~morons~~ \"contrarians\" like Alan Feduccia) was the explosion of feathered bird fossils and feathered dinosaur fossils that started coming out of China in the '90s. Some dinosaurs were even originally described *as* birds, so covered with feathers were they, and only after publication recognized as bird-like dinosaurs instead of dinosaur-like birds. This would have been right around 20 years ago, just after your school experience. By the end of the '90s pretty much every paleontologist was back on board Cope and Huxley's 130-year-old \"birds are dinosaurs\" train, and hopefully your teacher was, too."
]
}
|
[] |
[] |
[
[],
[]
] |
|
8kr95f
|
why sometimes a browsee doesn't recognize the file size of a download
|
Why are some downloads marked as 'unknown file size', while others are known beforehand?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8kr95f/eli5_why_sometimes_a_browsee_doesnt_recognize_the/
|
{
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"The download starts with some headers which tell your browser about the file - things like what type of file it is and whether it has been compressed. The headers can include the file size, but they don't have to. The server may not even know the file size when it sends the headers, because it may be generating the file on demand rather than just reading it from disk.",
"When you're downloading a file, the website just gives you multiple blocks of data one after another. At some point it will close the connection which tells your browser that the file is complete. Your browser generally has no idea how large a file will be until it is finished downloading. The website can tell the browser the expected file size at the start of the download, but it isn't required to do so and the information might also be wrong. That's why a download sometimes goes above 100% completion. ",
"Server needs to tell broswer file size first.\n\nIf he does not, browser does not know so it can just wait till server finished sending file."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
61x63y
|
how do protons, neutrons, and electrons form intelligent life?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/61x63y/eli5_how_do_protons_neutrons_and_electrons_form/
|
{
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"dfi1ca0",
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"text": [
"You can't understand the process in a single step, you need\n\n* Physics to explain how subatomic particles form atoms\n* Chemistry to explain how atoms form molecules\n* Biology to explain how molecules form living things\n* Neuroscience to explain how nervous systems work\n* Cognitive science to explain how intelligence works\n\nAnd the above is still a massive oversimplification.",
"Philosophy has pondered this question for millennia, and there are no easy answers. Here's a few thought experiments to get you started:\n\nYou have a person in a room, who receives Chinese characters on a piece of paper and must return a piece of paper with a response, also in Chinese. The person doesn't speak Chinese, but the room contains books with detailed instructions on how to manipulate the characters, such that the output makes sense. Does the room 'understand' Chinese? ([Searle's Chinese room](_URL_0_)). \n\nSay you have a being called a [philosophical zombie](_URL_1_). It does everything a human can do and appears to have consciousness. But it has no internal experience, no qualia, and no sentience. What's the difference between this and an actual person? How do you know everyone except yourself isn't a p-zombie?"
]
}
|
[] |
[] |
[
[],
[
"https://en.wikipedia.org/wiki/Chinese_room",
"https://en.wikipedia.org/wiki/Philosophical_zombie"
]
] |
||
89wlmu
|
What happened to United Empire Loyalists who moved to England?
|
After the American revolution many of the people who had remained loyal to the Crown were moved to Upper Canada and Nova Scotia. Is there any record of Loyalists migrating to England? If so, is there any record of how their lives turned out there ?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/89wlmu/what_happened_to_united_empire_loyalists_who/
|
{
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"text": [
"While much more has been written about the loyalists who landed in Nova Scotia (part of which became New Brunswick in 1784) and others to Upper Canada, there is significantly less about the large number of loyalists who landed in England and the British Isles. You should certainly get your hands on Mary Beth Norton's *The British Americans* as this is EXACTLY what she outlines. There was a decent size population of American refugees in London. For the most part, they remained separated by their regions they came from, Carolinians frequented the \"Charleston Coffeehouse,\" while New Englanders had their own hangouts. Just like in Halifax or Barbados, the Americans refugees were often looked down upon in London. Many Britons distrusted their American cousins who seemed prone to republicanism. As the war took a turn against British interests, many refugees gave up on hopes of returning to the Americas and moved out of London into the English countryside. Post 1783, many refugees who fled to Nova Scotia found the climate inhospitable and joined the earlier London contingent. Norton's book highlights some of the struggles and triumphs of this crowd. For one particularly interesting narrative, and one closely associated with my research, check out Carol Berkin's *Jonathan Sewall: Odyssey of an American Loyalist*, which documents one mans movement from Massachusetts to London and eventually to St. John New Brunswick. Also, check Maya Jasanoff's highly acclaimed *Liberty's Exiles*. You can catch her talking about that work [here](_URL_0_). ",
"There certainly were some Loyalists that moved to England after the Revolution. These people tended to be among the wealthiest and most respected Loyalists, able to draw upon the financial and social connections that enabled them to survive in English society. The examples I'll focus on here all hailed from New York, as the most visible Loyalist leaders from that state all went to England during or after the war. Mary Beth Norton concluded that between 7,000 and 8,000 loyalists - almost all of them white - fled America to England. Maya Jasanoff challenges this claim in her very readable book *Liberty's Exiles,* suggesting that 8,000 should probably be the lowest acceptable number of white refugees, and adding in Cassandra Pybus' estimate of 5,000 black refugees. To reach her 8,000+, Jasanoff includes Loyalists who fled first to East Florida, then to England after the British ceded that territory to the Spanish at the end of the war. \n\nMany of the refugees who fled to England appeared before Parliament's Loyalist Claims Commission in an effort to be reimbursed for the properties they lost for the loyalty to the crown. Their testimonies provide an invaluable resource in tracing the shape of the civil war inside the American Revolution. On the main, any relief granted by the LCC tended to be disappointing, never equally, and sometimes not even approaching, the sums lost. To be fair to Parliament, fully paying out the more prominent refugees would have been a substantial undertaking, as some loyalists had owned estates the size of counties. One of the main subjects of Jasanoff's book, for example, is Beverly Robinson. Robinson and his father-in-law, Fredrick Philpse, owned much of modern-day New York's Putnam and Dutchess Counties.\n\nStill, the losses the most fortunate of these families were able to recoup, paired with their sterling military reputation born of hard fighting in the Revolution, secured these families entry into the British gentry. Robinson and some his family (his eldest sons opted for Canada over England), for example, settled as renters in the London suburb of Mortlake, joined by several other Loyalist families in the vicinity. Still, this small social scene apparently provided little comfort to the refugees, who complained until their deaths of feeling out of place and adrift.\n\nA notable exception to this stagnation were those loyalists who remained in the British military. Oliver de Lancey was not a Loyalist in the traditional sense: though he was born in New York, he went to school in England and joined a regular regiment of the British Army in 1766. Despite his American origins, he became Barrack-Master-General of the British Army, a very senior general staff posting, in 1794. Two years later, he became a Member of Parliament. An American-born relation of his, William Howe De Lancey, died serving as a member of Wellington's staff at the Battle of Waterloo, cutting short a promising military career that had already netted him one of the most coveted staffing jobs in the army. Fredrick Philipse Robinson, son of Beverly, also secured a general's commission, fighting the French in the Peninsular Campaign during the Napoleonic Wars before being assigned to command a brigade tasked with invading New York from Canada during the War of 1812. Other De Lancey and Robinson sons became colonels, itself no small accomplishment.\n\nWhat's remarkable about both the London and Canadian Loyalist families is how many of them moved back, often during the lifetime of the generation that fought (survived?) the Revolution. Members of the loyalist Robinson, De Lancey, Van Schaak, Colden, and Dyckman families - all of whom lived in London during or after the Revolution - returned to New York at some point. Some even regained their families' pre-war social standing. Peter Van Schaak, who had been a friend of John Jay before their political ideals drove them apart, tutored law students for the bar in the upstate town of Kinderhook (on the advice of Jay, he stayed out of even local politics, lest anyone take exception to a Loyalist trying to tell Patriots what to do). Some of Robinson's sons became successful merchants in New York, joined by other Loyalists who had returned from Canada like the Depeyster family. Cadwallader D. Colden, grandson of New York's last royal lieutenant governor and son of an outspoken (and eventually exiled) Loyalist, spent his youth either in British-occupied New York City or in London, but this did not stop him from becoming NYC's mayor in 1821.\n\nIn summary, the fate of the loyalists was a mixed bag. It should be no surprise that those who were wealthy and successful in America generally found some way to remain so in England. What is surprising is the extent to which these Loyalists, who had been chased from their homes by their neighbors as traitors, continued to see themselves as fundamentally American and out of place anywhere else. More surprising still is the ability of many of these families, within two generations from the end of the Revolution, to return to America and integrate into the young United States.\n\nSources:\n\nMaya Jasanoff, *Liberty's Exiles*\n\nValerie McKito, *From Loyalists to Loyal Citizens*\n\nThomas Flexner, *States Dyckman*"
]
}
|
[] |
[] |
[
[
"http://library.fora.tv/2015/10/23/Global_Migration_of_American_Loyalists"
],
[]
] |
|
1kbdrz
|
Can anybody explain the historical Jewish tradition of putting stones on headstones?
|
I know that Christians put flowers on gravestones but I understand that people of the Jewish faith often put stones upon the headstone of dead relatives. Can any historians here explain this tradition and where it stems from?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1kbdrz/can_anybody_explain_the_historical_jewish/
|
{
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"Ultimately, to my knowledge, the origin is unclear. As the [Jewish Virtual Library](_URL_5_) says:\n\n > Unlike people from other religions, Jews do not typically place flowers at gravesites. Instead, they often place stones on the grave or tombstone. **The origin of the custom is uncertain, though it may relate to ancient times when a pile of stones was used as a marker.** The most common explanation is that placing stones is a symbolic act that indicates someone has come to visit and the deceased has not been forgotten.\n\nTo go further, large piles of stones, called [cairns](_URL_4_), are quite common as markers. The site of Thoreau's cabin on Walden Pond, for example, is marked by a cairn. Cairns have to be periodically maintained, and the maintenance is simply taking a stone that has fallen off and putting it back on top.\n\nDavid Wolpe, almost certainly the best known Conservative rabbi in the world and called by Newsweek the most influential rabbi in America, [has written](_URL_7_):\n\n > The practice of burying the dead with flowers is almost as old as humanity. Even in prehistoric caves some burial sites have been found with evidence that flowers were used in interment. But Jewish authorities have often objected to bringing flowers to the grave. There are scattered talmudic mentions of spices and twigs used in burial (Berakhot 43a, Betzah 6a). Yet the prevailing view was that bringing flowers smacks of a pagan custom. \n\nThere are a variety of beliefs about what the stones mean. Wolpe points out that some customs indicate that the stones help weigh down the soul of the dead, as the grave is the *beit olam*, the eternal home. Many of the mystical explanations for the ritual involve helping the souls \"stay put\" until the time of bodily resurrection (resurrection is the 13th of Maimonides's [Principles of Faith](_URL_3_)). For the consequences of a wondering soul, see also [dybbuk](_URL_1_), which the \"dislocated soul of a dead person\". \n\nYou can find more explanations [here](_URL_2_), including:\n\n * the belief that rich and poor must be buried alike (so no extravagant floral arrangements)\n\n * placing edible items in the basket is \"wasting G-d's bounty\". Placing fragrant flowers is similar. This reminds me of the first part of [Bel and Dragon](_URL_0_).\n\n * \"It is forbidden to use or benefit from the casket or anything associated with the dead—even the earth which covers them. As such, enjoying the fragrance of flowers placed on graves would be forbidden, and planting flowers there in the first place is just inviting trouble.\" (This I did not know about)\n\nUltimately, though, it's the tradition, and in Judaism, [minhag](_URL_6_) (\"custom\") is very important. Old customs that date from before the Talmud are seen as universally binding. ",
"This is actually a bit of a mystery. Like most Jewish practices, there's written evidence that talks about the custom's existence long after memory of why it was around has been forgotten, leaving only speculation. Perhaps the most famous of these is the practice of *shukleing*, or swaying side-to-side or forward and back during prayer, though for that we have earlier speculation, and it's a much more widespread custom.\n\nA few theories are that their permanence is symbolic to reflect the (hopefully) permanent nature of the person's memory (which corresponds with the line traditionally written on Jewish grave markers, \"may their soul be bound up in the chain of life\"), for superstitious reasons, as a convenient way of marking graves in the absence of gravestones (which I imagine were scarce in some Jewish communities, given the skill needed to make them and their expense. Additionally, it's traditional to put up a permanent marker a year after the funeral, so a temporary marker makes sense), to save the trouble of gathering flowers, which aren't always available, or because the festive nature of flowers are inappropriate for a cemetery. Personally, I think the advantage of having a temporary marker if headstones are unavailable or during the first year after death makes the most sense, but there's nothing solid either way, and superstition also would make sense.\n\nBut we'll probably never know."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Bel_and_the_Dragon#cite_ref-8",
"http://en.wikipedia.org/wiki/Dybbuk",
"http://www.chabad.org/library/article_cdo/aid/1218970/jewish/Flowers-Jews-Gravesites.htm",
"http://en.wikipedia.org/wiki/Maimonides#The_13_principles_of_faith",
"http://en.wikipedia.org/wiki/Cairn",
"http://www.jewishvirtuallibrary.org/jsource/Judaism/graves.html",
"http://en.wikipedia.org/wiki/Minhag",
"http://www.myjewishlearning.com/life/Life_Events/Death_and_Mourning/Burial_and_Mourning/Graveside_Service/Stones.shtml"
],
[]
] |
|
sg6di
|
What would theoretically happen if you broke the speed of sound underwater?
|
askscience
|
http://www.reddit.com/r/askscience/comments/sg6di/what_would_theoretically_happen_if_you_broke_the/
|
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"May I also ask, would it be relevant if it's the speed of sound through water, or the speed of sound through air?\n\nBecause, correct me if I'm wrong, sound moves faster through water then air.",
"There's actually a Russian torpedo that breaks the speed of sound in water. I'm posting from my phone so not sure how well linking works, but here goes: _URL_0_. \nBasically, when the torpedo moves faster than sound, it creates an effect called supercavitation. The force of the Shockwave coming off the nose cone of the torpedo pushes the water away from the edges of the body of the torpedo, the cavity left then being filled with exhaust gases from the torpedo's engine. Since the torpedo is now in contact with air rather than water, drag is significantly reduced allowing it to travel at extremely high speeds. Not sure if that satisfied the mechanics behind your question, but definitely an interesting real-world example of supersonic things underwater.\n\nEdit: I failed hard! this torpedo obviously doesn't travel at supersonic speeds, but is an interesting phenomenon that occurs underwater at high speed. Read some of the replies below for a better explanation of this phenomenon and better info on the project I was trying to describe.",
"The problem is that breaking the speed of sound would require water to be pressurized immensely. The speed of sound in water is around 1.400 m/s. If we use Bernoulli's equation, to avoid cavitation we would require almost 9000 atmospheric pressures. \n\nThe force required to break this barrier would also be immensely high, as the drag suffered by objects at that speed would be huge- pressure drag (the dominant type of drag at those speeds) scales up like the density*velocity^2. If you think that water is 1000 times denser than air, and its speed of sound is 4 times higher, this requires about 16.000 more force just to overcome the drag.\n\nOn your question, if we were able to find water sufficiently pressurized and sufficient force to accelerate the object, I don't think anything different would happen which doesn't happen when breaking the speed of sound in air.",
"Closely related to this, there are shrimps called 'snapping shrimps' which are capable of producing a loud snapping sound. \n\n'The snap can also produce sonoluminescence from the collapsing cavitation bubble. As it collapses, the cavitation bubble reaches temperatures of over 5,000 K (4,700 °C).'\n\n_URL_0_\n\nIs this breaking the speed barrier in water at all?",
"I found this source looking through the previous threads that [someone else posted](_URL_0_) - it details a supercavitation research project. I haven't read it all or had time to summarise it, but here's a choice paragraph:\n\n\"An underwater test range was constructed in the NUWC tow tank and has been used in over 50 supercavitating high-speed projectile tests in support of the Supercavitating High-Speed Bodies (SHSB) program. This program involves basic research into very high-speed undersea projectiles. Application of supercavitation drag reduction at munitions scales can result in projectiles capable of supersonic velocities (exceeding 1500 m/s in water) over short ranges. The tests were executed by the SHSB Test Team at NUWC Division, Newport, Rhode Island, USA.\"\n\n_URL_1_",
"Maybe not the answer you're looking for, but it's gonna be **very very hard** to even get close to the speed of sound in water. Friction is going to be enormous. You're gonna spend humongous amounts of energy just to keep moving. Not sure what would happen to the front end of the object - it must somehow withstand the huge amounts of heat constantly dumped on it, or else it would probably melt off.",
"OP asked what would happen, not if it could happen people.",
"First, let's calculate the local speed of sound. Acoustic velocity can be [determined using material density and bulk modulus](_URL_2_): \n\nv_sos_water = sqrt(E / ρ)\n\n > = sqrt{ (2.15 · 10^9 Pa) / (1030 kg/m^3 ) }\n\n > = 1444.7 m/s = 3231.7 miles per hour\n\nFor comparison, the local speed of sound in air at sea-level standard is:\n\nv_sos_air = sqrt( gamma · R_air · T)\n\n > = sqrt{ 1.4 · (287 J/kg·K) · (288.16 K) }\n\n > = 340.27 m/s = 761.16 mph\n\nAnd the local speed of sound in pure water vapor:\n\nv_sos_vapor = sqrt( gamma · R_vapor · T)\n\n > = sqrt{ 1.33 · ([461.5](_URL_1_) J/kg·K) · (373.13 K) }\n\n > = 478.56 m/s = 1070.52 mph\n\nFor the sake of discussion, let's let our theoretical vehicle take the form of a perfect [Sears-Haack body](_URL_0_) made out of an indestructable material. From my aerodynamics textbook, vessels that travel through air and begin to reach sonic speeds reach a point called the critical Mach number, the speed at which the local flow of air over the body begins to experience sonic effects; this first occurs on the point of lowest pressure compared to the surrounding fluid pressure. Such effects include wave drag, transonic drag rise, thermal heating, and the formation of local shockwaves due to the compressibility of air. Since water is much denser than air, I imagine that as our theoretical hydrosonic vehicle would first begin to have an immense amount of drag as it approached half of the underwater Mach 1. Since incompressibility effects are difficult to occur underwater, drag would continue to have a profound effect on the body, and if we keep magically speeding up, the local boundary layer fluid pressure would exceed the vapor pressure of water, and due to the tendency for high-speed bodies to form shockwaves in air, the same phenomenon would manifest itself as [supercavitation](_URL_4_) underwater.\n\nAs we get closer to underwater Mach 1, the shearing between the water and the leading edge of the vehicle would probably cause enough heating to start vaporizing the water around it and surround the vessel in high-pressure water vapor, which while still low in compressibility, is much more compressible than water, and since the velocity of the vehicle is already exceeding half of the underwater Mach 1, it would already be going at about Mach 1.5 in water vapor. If the water vapor is compressible enough, the vehicle would be capable of forming [Mach waves](_URL_3_); if enough Mach waves form, you will get full-on oblique shockwaves.\n\nI realize that my entire explanation is sort of \"hand waving\" and lacks empirical evidence, but I imagine that our magical hydrosonic vehicle would behave exactly as any supersonic aircraft would, except with an extra layer of incompressibility to overcome before being able to form shockwaves."
]
}
|
[] |
[] |
[
[],
[
"http://en.m.wikipedia.org/wiki/VA-111_Shkval"
],
[],
[
"http://en.wikipedia.org/wiki/Alpheidae"
],
[
"http://www.reddit.com/r/askscience/comments/sg6di/what_would_theoretically_happen_if_you_broke_the/c4dvvxp",
"http://ftp.rta.nato.int/public//PubFullText/RTO/EN/RTO-EN-010///EN-010-15.pdf"
],
[],
[],
[
"http://en.wikipedia.org/wiki/Sears-Haack_body",
"http://en.wikipedia.org/wiki/Water_vapor",
"http://www.engineeringtoolbox.com/speed-sound-d_82.html",
"http://en.wikipedia.org/wiki/Mach_wave",
"http://en.wikipedia.org/wiki/Cavitation"
]
] |
||
fqdvzk
|
price gouging during declared emergencies. how can hospital still charge $45 for an aspirin.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/fqdvzk/eli5_price_gouging_during_declared_emergencies/
|
{
"a_id": [
"flpygg0"
],
"score": [
3
],
"text": [
"Those are the normal prices and price gouging laws only apply to raised prices in emergencies, not having high prices all the time.\n\nIt's one of the huge problems of US healthcare and something that is coming to light quickly during this pandemic."
]
}
|
[] |
[] |
[
[]
] |
||
3nddw9
|
why does it take so much less time to get fast food from a drive through than to get it from inside?
|
I've noticed this at places such as Steak N' Shake and other "higher" quality fast food places. Do they just take longer to make it feel better quality?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3nddw9/eli5_why_does_it_take_so_much_less_time_to_get/
|
{
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"cvn0740",
"cvn11d6",
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"cvn7po9",
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"cvn9kr7",
"cvnbd1k",
"cvnbl2a"
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"score": [
56,
6,
12,
3,
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"text": [
"They track the time that cars spend at the drive thru window and have to get it under a specific time. Because of this, they tend to prioritize and rush drive thru orders compared to walk ins.",
"For one drive thru lines are timed, the workers have x number of seconds from the time the car pulls up to the menu to the time they pull away with food. I've known people to work at several of the fast food chains and this is confirmed to be an essential metric. To the point that staff from management down can be completely reorganized if the goal is consistently not reached. \n\n\nAs for why that is.. I have no good explanation. My best guess is someone who goes inside the restaurant has already shown they're in less of a hurry by parking their car and walking inside. Even if they're ordering to go they made a conscious decision to be in less of a rush.\n\n\nAlso when you order inside its typically one person ordering for one person. In the drive thru you can be ordering for you and your friend, or your entire family, or half the office and you still expect your food to come up in a normal amount of time. ",
"I worked at a Culvers in high school. We had a speaker in the kitchen so that we could hear the drive through customer as the order came through. We were throwing it down while you ordered it. This was especially true at slower times where we didn't have 1,000 things going on. Drive Through also had one employee dedicated to getting you your food asap. It wasn't prepped by one, ran by another etc. That person was generally one of the faster/better/experienced workers, cause no one wants drive through mistakes. ",
"From my own experience when I worked fast food, it's because generally, there is a whole assembly line devoted to the drive through - An order taker, a cashier who takes your money while the order taker takes more orders and makes more drinks, a grill person making meat for everyone, a sammich maker making the sammiches, a fry person making the fries for everyone, a person putting the food in a bag - and all of these people have headsets on and can hear what's coming in, making the food and estimating how much more product to cook / fry / etc. Everyone is close together and the person bagging up the food generally doesn't have to goo to far to reach for the fries, pick up the sammiches, turn to the window.\n\nWhereas the front counter may have one person taking orders, one person making the sammiches, but not being able to start making the food until it pops up on the screen, and if they are Lucky, one person putting all the food on trays for you. If they aren't lucky, the cashier then has to stop taking orders to fill the trays too - which takes even longer for everyone else. \n\nHowever in the drive through, it can be very compulsively organized bags 1 2 3 4 based on exactly how the order comes in and the cars the bags belong to. EVERY order is to go so the bags can be lined up with straws and napkins and utensils and ready to drop the food into. But up front it's whatever food comes up first and is it to go? for here? and what else goes on the tray? A burger for tray one is done, but the chili for tray two is done, and the salad for tray three is done, there's a burger for tray two, did the special fries come up for tray one? constantly checking the tray versus the order... \n\nit's just - a lot different and half the crew getting the food to you inside, versus what's devoted to keeping the cars churning in drive thru. \n\nAnd yes, the drive thru is compulsively timed, in pieces and as a whole. How long were they at the menu? How long did it take to pay? How long did they wait at the window for their food? Total time from pull up to drive off? \n\nWhile it sucks that there isn't more staff there to help the inside customers - it's a good thing they are trying to get cars through fast. Gas consumption, exhaust production - move these metal monsters in and out folks! ",
"I think it's mostly perception. While drive thru is timed, you can't see all the other orders going out ahead of you when you are in a vehicle. As well, you are more comfortable in your vehicle so the time passes more quickly than you are standing there trying to figure out what to do with your hands. Lastly, you probably don't realize how long you waited to pay after ordering and how much lead time they have versus when you order and pay at the same time inside. ",
"I've timed myself at the counter against friends in the drive through and the times have always been pretty equivalent with a slight edge to the counter for speed.\n\nThis is just at my local mcdonalds and I think it's because too many people are now sitting at the drive through, but I'm not sure if the drive through is much more than average. ",
"I worked at KFC in a smaller town. The faster, more experienced employees were put on drive through.",
"Have you ever gone into Chick-fil-A and done this because going inside is about 10000x faster",
"My wife went in to get coffee, I was in parking lot and counted 27 cars go thru the drive thru before she came out! (Mcdonalds)",
"A few reasons: (Source - Was a manager at a McDonnalds for awhile)\n\n- Most fast food joints make the majority of their profit in the drive through. At my restaurant, almost 70% of the store's revenue came through the drive through. Prioritizing the drive through makes sense when most of your clientele purchases that way.\n\n\n- People are way less patient when they're in a car. They are already on the go and expect their food faster. People in the restaurant are usually a little more chill. They take time to go get some ketchup, fill their drink, etc. "
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
|
1iyowr
|
when choosing from a menu, why am i "in the mood" for a certain type of food.
|
One night it's pasta, the next fish, then steak, and so on...
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1iyowr/eli5_when_choosing_from_a_menu_why_am_i_in_the/
|
{
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"cb9c2zw",
"cb9c3gh",
"cb9fde4"
],
"score": [
6,
20,
2
],
"text": [
"Because your body requires many different kinds of nutrients to run smoothly, and no single food has all of them. So usually when you're craving something, your body is \"low\" on something and wants to replenish.",
"Nutrient cravings combined with enjoyment/emotional attachment to various foods.",
"How can I always be in the mood for ice cream?"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
j2mwb
|
why do we need constants in formulas? is it because our units or number system are flawed?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/j2mwb/why_do_we_need_constants_in_formulas_is_it/
|
{
"a_id": [
"c28muot",
"c28mvsn",
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"score": [
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2,
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"text": [
"it has nothing to do with flawed numbering systems. constants are derived from the universe around us. whether in science or in math, they are either measured or calculated to make the formulas true.\n\nfor example, regardless what numbering system we use, the circumference of a circle, divided by its diameter will always be pi",
"In some cases yes, for instance take E=mc^2 (let's skip the more useful version) if you set the speed of light to one with all other speeds being fractions under one, you end up with energy==mass, which is to say that both are manifestations of the same overall phenomenon. \n\nSince most unit systems are derived off arbitrary things like water, because it is so common you end up needing a lot of conversion factors. Also different unit systems require conversion factors of their own, such as getting Kelvin to Fahrenheit.\n\nTherefore we have unit systems such as [Natural Units](_URL_0_) which is different from metric or imperial and allows a lot of complicate math to be shrunk into small equations.\n\nThen when you have numerically based formula (based off observation and statistics) the constants are just there to make sure the equation fits a certain curve. These formula aren't natural in any significant way and are derived from just measuring something at a bunch of different settings and making an equation up that generally fits the experimental data.",
"Hmm. Let's see if I can explain this. Our numbering system was originally used to count whole items, such as 5 rocks. Over time the same concept has been applied to less straight-forward concepts such as length and electric charge. Now we can't just say we have 1 length because how long is that? For this reason we've come up with units such as the foot, the meter, the second. These make it convenient to say something is 1 foot long. But how did we get these units? In most cases we actually measured some value and stated that to be one of something. Now we get to constants in formulas, these manly allow you to convert between these standard units so you can use what is convenient at the time. So we need constants so we can change what we're talking about. For example if we're converting cents to dollars we multiply by 1/100 so we can talk about dollars even if we only have how many cents we have. So it isn't because the system is necessarily flawed, it's because at different times we need to use different units because it might be all we have. The only way we wouldn't need a constant is if the units we're designed to be equal when converting, but we couldn't do this for all units at once."
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Natural_units"
],
[]
] |
||
10lcdu
|
Whenever Marine One flies over my house, my TV flickers out. Why?
|
askscience
|
http://www.reddit.com/r/askscience/comments/10lcdu/whenever_marine_one_flies_over_my_house_my_tv/
|
{
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"c6ehgyy",
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],
"score": [
2,
3
],
"text": [
"Any type of radar guided object could operate at any frequency, so Marine One would obviously block out all frequencies except it's own exclusive networks. \n\nIt would be no sense for a high personnel designated air craft to only jam a specific, highly common signal, and if it did so, would greatly jeopardize anyone on the helicopter. \n\nHope this helped. ",
"Multi-band airborne jamming has been around for a while [e.g. EC-130](_URL_0_), so such a device mounted on Marine One is certainly possible.\n "
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/EC-130H_Compass_Call"
]
] |
||
i9li0
|
Why do these gifs give a vivid impression of 3D, while video doesn't?
|
[This](_URL_0_) link was just posted over in /offbeat. It has gifs of stereoscopic photographs with the image quickly alternating between the two perspectives. This gives me a very vivid impression of being 3D, while a shot from a film with a camera moving around the scene doesn't, though I'd have thought the cues that my brain is picking up on to form a 3D image would be the same in each case. Why the difference?
|
askscience
|
http://www.reddit.com/r/askscience/comments/i9li0/why_do_these_gifs_give_a_vivid_impression_of_3d/
|
{
"a_id": [
"c220059",
"c2208md",
"c220a5r"
],
"score": [
5,
2,
28
],
"text": [
"It's because video doesn't shake back and forth like that. It would look 3D if it did. \n\nThe feeling of 3D appears when each eye sees a slightly different picture, that's how you can feel distance. With picture moving like that you can see the angle of the photo and the distance between objects in it, as objects further away move a bit more than objects closer to the camera.",
"Sorry to get a bit off-subject here, but does anyone know how to create a 3D-viewing apparatus like the one the Geisha is perusing?\n\nI think that it could be used to view videos in 3d if the two photographs were replaced by videos.",
"What you're seeing is called [structure from motion](_URL_1_). Your brain uses the motion in 2D (along your retina) and the assumption that the world is fairly rigid and static (the complex motion doesn't come from weird warps in space) to infer vection (movement of the viewer) or object motion in 3D. This 3D motion information allows you to understand the structure of the objects in the scene.\n\nThe motion in the images is actually fairly fast. When you have similarly fast panning/rotating shots in a video, you get a similarly strong 3D affect. \n\nWhat comes to mind is the view from a [helicopter-mounted cam flying through a canyon](_URL_0_). Notice that the faster the movement, the stronger the 3d effect."
]
}
|
[] |
[
"http://www.howtobearetronaut.com/2010/06/old-japan-in-3d/"
] |
[
[],
[],
[
"http://www.youtube.com/watch?v=duU3aaonWuk",
"http://en.wikipedia.org/wiki/Structure_from_motion"
]
] |
|
46qiev
|
Do the constellations change/ look different from the Moon, Mars?
|
askscience
|
https://www.reddit.com/r/askscience/comments/46qiev/do_the_constellations_change_look_different_from/
|
{
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"d073frd",
"d073upm"
],
"score": [
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19
],
"text": [
"Not by any perceptible amount. You'd have to go very very far away (a comparable distance to how far apart the stars in constellations are from each other) before you'd notice a difference.",
"The constellations do not appear to change as the Earth orbits the Sun, and the Earth has an orbit that is 300 million km (186 million miles) across, so you can see that going to the Moon (400000 km away) or Mars (never more than 401 million km away) won't change what the constellations look like. \n\nIn fact, you'd have to go much, much farther away to see any effect. Even from Alpha Centauri, about 4 light-years away, there's not much effect. [Here](_URL_1_) is an image showing that made by /u/Olog and linked to in [this](_URL_0_) Reddit post from about a year ago."
]
}
|
[] |
[] |
[
[],
[
"https://www.reddit.com/r/askscience/comments/2tp0qd/which_constellations_would_differ_if_viewed_from/co14oak",
"http://www.imgur.com/a/I2Amc"
]
] |
||
6zwjnb
|
how can the brain sort itself out during an full convulsive seizure?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6zwjnb/eli5_how_can_the_brain_sort_itself_out_during_an/
|
{
"a_id": [
"dmyuf26"
],
"score": [
3
],
"text": [
"I think you are drawing too close a parallel between a human brain and a computer. An electrical signal in the brain is not like a task in a computer program where each step needs to be sequentially executed in order to continue. Misinformation from one or two \"bad\" signals will not cause a seizure the way that an error in a program will cause some downstream hangup or glitch. There is not a bottleneck of information processing where individual firings need to be sequentially addressed or sorted out. A nerve firing is the output of its own information processing. A neuron takes excitatory or inhibitory input from many synapses and when it reaches an excitation threshold, it produces its output. It is immediately ready to receive more input and produce more output. The brain has many mechanisms that are designed to prevent runaway signaling, and these will be activated when runaway signaling happens. Currently, there is no definitive explanation for exactly how seizures end, but it's known that neurons are still able to fire after a seizure."
]
}
|
[] |
[] |
[
[]
] |
|
2nqyr1
|
Has Britian been self sufficient in food since the industrial revolution?
|
I realise this is a rather broad question, but I'm not entirely sure where to look to find the answer. I understand that Ireland and the rest of the Other Island in the British Isles acted as seperate economic systems in this period so if it seems one Isle has been self sufficient but not another I'd like hear about that as well.
Thanks.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2nqyr1/has_britian_been_self_sufficient_in_food_since/
|
{
"a_id": [
"cmhf1w4"
],
"score": [
2
],
"text": [
"No, Britain has not been self-sufficient in food since basically the late 18th century. By that point, it became clear to British policy-makers that not only would Britain no longer be an exporter of food, as it had been in much of the early modern period, they would have to import in years of poor harvests. In years of abundance Britain could mostly feed itself. \n\nThe situation was largely disrupted by the French Revolutionary and Napoleonic Wars, however, as imports were harder to come by and prices rose substantially. This actually led to some important pieces of legislation with long-term consequences, including the implementation of the Speenhamland System in 1798 and the passage of the Corn Laws in 1815. The Corn Laws were a series of duties on imported grain implemented at the conclusion of the wars in order to keep grain prices high, and to continue the period of prosperity for landowners. Britain's population growth, however, meant that the problem of short food worsened over time. This led to the period (retrospectively) called the \"Hungry 40s,\" and the repeal of the Corn Laws in 1846: with their repeal, we get proper \"Free Trade\" in food for Britain. \n\nAt that point, in 1846, British farmers typically produced about 75% of the wheat that Britons consumed. By World War I, less than 70 years later, that figure had dropped to less than 20%. And, in addition to wheat, Britain imported massive quantities of preserved and refrigerated meat from the US, Argentina, and Australia; butter and other dairy products from New Zealand, and continental Europe; and an assortment of other products like tropical fruits. These added to Britain's prior dependence on the tropical world for its chemical stimulants like coffee, tea, chocolate, sugar, and tobacco (not a food, but useful to consider in the same category), as well as spices. This utter dependence on overseas farmers was obvious their enemies in both World Wars, as evidenced by the resources Germany put into submarines. Their principal goal was to disrupt the trade in food between Britain the rest of the world--especially North America--enough to force the UK to a negotiated peace. Convoys, the US and Royal Navy, rationing, and government support for intensive agriculture prevented this from happening both times. In 1947, the wartime support for agriculture (itself a fascinating story of top-down environmental management) was made permanent with subsidies for intensive agriculture. Britain abandoned the free market for its food supply, and has been much more capable of feeding itself since then.\n\nAlso, I should point out that Ireland was in no way part of a separate economic system in the 18th and 19th centuries. It has long served as a combination of captive market for British goods and a supplemental granary for British stomachs. \n"
]
}
|
[] |
[] |
[
[]
] |
|
qir2q
|
Do fluctuating temperatures actually increase risk of illness?
|
Living in Michigan I hear people complain with relative frequency that rapidly fluctuating temperatures make people sick. Knowing that the concept that going outside in cold weather with wet hair gives people pneumonia is a myth, I find this hard to believe. Is there any veracity to the idea that temperature changes cause illness?
|
askscience
|
http://www.reddit.com/r/askscience/comments/qir2q/do_fluctuating_temperatures_actually_increase/
|
{
"a_id": [
"c3y020r",
"c3y1ij7"
],
"score": [
8,
3
],
"text": [
"The answer is pretty dynamic actually. The colder months of the year can be linked to a higher chance of catching a cold or the flu but not because of the lower temperature's effect on our body. More so it's the temperature's effect on where we spend most of our time(inside/outside). \n\nWhen the weather gets colder people end up spending more time inside. **If you have more people indoors in close proximity to each-other, viruses and germs will be spread more easily.** Also during the winter months we see a decrease in humidity both outside and inside. **The most common cold-causing viruses survive better when humidity is low.** \n\n Low humidity also makes the **inner lining of your nose drier** which lowers it's ability to filter the air you breath. This **increases vulnerability for a viral infection.**\n\nArticle on the Causes of the Common Cold from the National Institute on Allergy and Infectious Diseases: _URL_0_",
"I think it should also be worth noting that many doctors and specialists theorize that a lack of sunlight (ie- Vitamin D3) are factors that are conducive to increased sickness in the winter...\n\n_URL_0_\n\n\n_URL_1_"
]
}
|
[] |
[] |
[
[
"http://www.niaid.nih.gov/topics/commonCold/pages/cause.aspx"
],
[
"http://www.sharecare.com/question/avoid-sick-in-winter",
"http://www.truthaboutabs.com/prevent-sickness-increase-immunity.html"
]
] |
|
ewsnl1
|
Why do some parts of the world generally experience more vivid/'better' sunsets?
|
askscience
|
https://www.reddit.com/r/askscience/comments/ewsnl1/why_do_some_parts_of_the_world_generally/
|
{
"a_id": [
"fg5z5o8"
],
"score": [
13
],
"text": [
"The fluctuation in sunsets by location is to largely due to the particulate matter in the air. Since every particle has a different size, and refractive index, they cause light to refract, reflect or even diffract differently. Basically, these particles in the air, can cause light to bend/change direction and or polarise the light. This is what accounts for the different light intensity range you see across a sunset sky. The colours are mostly result of the refraction of light through different air particles/molecules."
]
}
|
[] |
[] |
[
[]
] |
||
5guq80
|
Does the motion of the Earth effect radio waves?
|
Are EM waves effected by the rotation of the Earth?
Would a listener to the East or West of a radio station experience altered reception?
What about in relation to the Earth's orbit around the Sun? Would the above listeners experience different reception at different times of day?
Do EM waves experience the coriolis effect?
What about wavelengths other than radio frequencies?
|
askscience
|
https://www.reddit.com/r/askscience/comments/5guq80/does_the_motion_of_the_earth_effect_radio_waves/
|
{
"a_id": [
"davhxdp",
"davhxvo"
],
"score": [
2,
6
],
"text": [
"The fact that electromagnetic waves seem to ignore the rotation of the Earth really bothered people from about 1887 when Michelson and Morley [proved that this was so](_URL_0_) and 1905 when Einstein published the theory of relativity. This is one of the most famous null results in physics history.\n\nYou can have atmospheric effects - shortwave radio works better in the winter - but photons themselves absolutely do not care that we're orbiting the sun at several km/s.",
"Remember there is no absolute frame in the universe speeds and positions can only be measured relative to one another. The speed of light and therefore radio waves is always the same no matter your reference frame. However if a transmitter is moving toward or away you will perceive a change in frequency known as the Doppler shift.\nI would imagine EM waves experience corolis effect but the rotation of the earth is so small compared to the speed of light it doesn't matter."
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Michelson–Morley_experiment"
],
[]
] |
|
1u7mx7
|
how come when i'm really high up (like on a building or something), there is a little voice in my head telling me to jump? is there any sort of evolutionary benefit to having the voice? or is it just our brains trying to kill us.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1u7mx7/eli5how_come_when_im_really_high_up_like_on_a/
|
{
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"cefapwu",
"cefb5j7"
],
"score": [
3,
2
],
"text": [
"Great question. Took more than a quick search to find this thread so no fault for asking, but [here](_URL_0_)'s a link that should explain it. Thoughts like this are apparently called 'intrusive thoughts.'\n\n:)",
"As it turns out everyone has this reaction, the \"I could stab this baby right now\" kinda thing is part of human evolution designed to show us that we are in control of the situation by doing the most spontaneous and unpredictable thing possible."
]
}
|
[] |
[] |
[
[
"http://www.reddit.com/r/explainlikeimfive/comments/1tnhlk/eli5_why_do_we_have_intrusive_thoughts/"
],
[]
] |
||
ruyz7
|
Question about the rate of pathogen evolution.
|
I've just finished reading "Nemesis" by Isaac Asimov, humanity has expanded to space and lives in thousands of "Settlements"; essentially self sufficient, isolated habitats scattered throughout the solar system.
Trade and most interactions are severely limited though because each Settlement has evolved it's own unique pathogen load which would obviously be harmful if it came into a new environment.
My question is whether this would happen and if so how quickly?
|
askscience
|
http://www.reddit.com/r/askscience/comments/ruyz7/question_about_the_rate_of_pathogen_evolution/
|
{
"a_id": [
"c48vyjd"
],
"score": [
2
],
"text": [
"It can happen. There is an offset in that pathogen and host tend to evolve together. A pathogen may have no effect on another group/species because the attack pathways are not the same.\n\nThis is why diseases tend to be restricted to a single species and there is little danger from meeting aliens and catching their diseases (H.G. Wells - War of the Worlds - the bacteria and/or viruses would have had little effect on a species that evolved on another planet).\n\nMany an island population has been decimated by diseases brought by European explorers.\n\nPathogens are continually evolving. AIDs and Ebola are thought to have developed in small African regions (possibly not in humans). Swine and Bird flu developed from non-dangerous strains in a short time (years)."
]
}
|
[] |
[] |
[
[]
] |
|
3xvhp4
|
why do most recipes and appliances ask specifically for cold water when the water will just be heated up?
|
I.e. Use cold water in a coffee machine......
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3xvhp4/eli5_why_do_most_recipes_and_appliances_ask/
|
{
"a_id": [
"cy8bmu8"
],
"score": [
2
],
"text": [
"Hot water can be sitting in water heaters for a while & pick up all sorts of metals & minerals. This may alter the chemistry of what's going on or it might just increase the rate at which mineral buildup occurs inside the appliance. Using cold water avoids the problems."
]
}
|
[] |
[] |
[
[]
] |
|
1xiq8h
|
in the game of thrones universe, some winters are longer than others. how?
|
I'm interested in both finding out why some winters are longer as explained by the book (fantasy/magic behind it) **as well as** being curious if something like drastic differences between season lengths is possible scientifically.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1xiq8h/eli5_in_the_game_of_thrones_universe_some_winters/
|
{
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"cfbojb4",
"cfbojjs",
"cfc1f6c"
],
"score": [
7,
6,
2
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"text": [
"Scientifically, there is a possibility for it, like if a planet has a weird axial tilt, or multiple stars in the solar system etc. But Martin has claimed that there is a supernatural reason for the long seasons, but hasn't discussed this in detail outside of what you find in the books. ",
"The reason for the random season length has not been stated in the books, but George R R Martin has explicitly stated that the reason is magical and not astronomical\n\nEarths seasons are caused by the tilt of the earth, and this is steadied by the gravitational pull of the moon. It is believed that without the moon then the axial tilt would be more erratic - changing the lengths of the seasosn - however this would be over dozens or hundreds of years",
"I theorize the length of the season has to do with the health of the kingdom. Similar to the Arthur legend, \"The king and the land are one.\" When the people and state of the kingdom are well you have a long summer, as summer is fair and good and full of plenty. When evil tides stir and darkness rules, a long harsh winter follows close on it's heels.\n \nThis isn't stated as far as I can recall in the books, just how I justify it in my own head."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
5nl852
|
What are the similarities & differences between trying to decipher Linear B & Indus script?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/5nl852/what_are_the_similarities_differences_between/
|
{
"a_id": [
"dcgsyuc"
],
"score": [
3
],
"text": [
"You might be interested in [this](_URL_0_) answer I wrote regarding the indispensable discoveries that help translate a language. I mention both Linear B and Indus script, but only briefly.\n\nThe biggest thing impeding translation, or really, intensive study, of the Indus script is the size of the \"texts.\" There are over 400 identified signs, yet the average length is just 5. With so many signs, it is almost certainly a symbolic, logographic system rather than a phonetic one. You can through all kinds of mathematical analysis at this with minimal results. \n\nWe do know that there are patterns. One study used Markov chains (the same algorithms used at /r/subredditsimulator) to look at common sequences^1. Markov analysis produces probability tables of what signs are likely to follow other ones, based on patterns from the known corpus. After running this analysis with all 3800 samples, the researchers were able to reliably conclude that there were distinct patterns used in different regions. The study lent slight credence to the belief that the script represents a spoken language, but nothing substantial.\n\nYet even if we were to unequivocally prove that the script represents a spoken language, we would be thousands of miles from any kind of translation. We have no bilingual texts (e.g. Rosetta Stones) and no clue what that spoken language could be.\n\nCompare that with Linear B, which uses known personal and place names, has exponentially longer tests, and is a (primarily) syllabic representation of Greek.\n\n\n---\n\n^1 Rao, R. P. N., Yadav, N., Vahia, M. N., Joglekar, H., Adhikari, R., & Mahadevan, I. (2009). A Markov model of the Indus script. Proceedings of the National Academy of Sciences of the United States of America, 106(33), 13685–13690. _URL_1_\n\n"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/2hpaum/with_computer_technology_at_such_an_advanced/ckuxvuk/",
"http://doi.org/10.1073/pnas.0906237106"
]
] |
||
1h5f2b
|
why do most job postings refuse to put base pay in their listing?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1h5f2b/eli5_why_do_most_job_postings_refuse_to_put_base/
|
{
"a_id": [
"caqzzbg",
"caqzzqx",
"car0qkg"
],
"score": [
4,
9,
5
],
"text": [
"Because they want to negotiate with you and pay you only what you'll ask for.",
"They're trying to attract qualified canidates, not simply people who want money. Money is also negotiable and it is expect that as a professional you already have an idea of what your pay will be. ",
"Couple main reasons:\n\n1. The company starts with a known pay range that they're willing to pay for someone who gets that position. They don't want to tip their hand and potentially overpay by including it in the posting.\n\n2. Keep competing companies in the dark. The hiring company doesn't want competitors to know what they're paying in case competitors can try to lure people away for more money or different benefits."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
4co3hg
|
Having trouble making sense of the famous "Now I am Become Death, the Destroyer of Worlds." Why is this said by Vishnu and not Shiva? See description:
|
First off, my apologies if this is the wrong sub to post in. I'll post it in /r/hinduism if that's better, it just seems like this sub is the most active. The interest in this stems from J. Robert Oppenheimer's speaking of this quote during the atomic bomb test. My question is, for someone who doesn't understand Hinduism all that well, why was this originally said by Vishnu if his role is more so the "protector"? Shouldn't this be more appropriate for the "destroyer" Shiva to say? Or are Vishnu and Shiva just different forms the same deity can take?
Thanks in advance! Let me know if this is a more fitting question for a different sub.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4co3hg/having_trouble_making_sense_of_the_famous_now_i/
|
{
"a_id": [
"d1lr74t",
"d1kbip9"
],
"score": [
2,
8
],
"text": [
"/u/restricteddata's piece on the duality of Kenneth Bainbridge's response of [\"Now we're all son of bitches\"](_URL_0_) is just as, if not more interesting than Oppie's initial statement.",
"In the actual _Gita_, it is Krishna, not Vishnu, who says the quote. Oppenheimer misattributes it. (Krishna is an avatar of Vishnu, but whatever.) \n\nAnyway. The quote is not about destruction, per se, it is about the inevitability of death. Oppenheimer's own translation is idiosyncratic. It is Krishna saying to Arjuna (a human prince who doesn't want to fight): _look, you don't want to kill all those people, but guess what: they're going to die anyway. It's not up to you whether they live or die. It's up to me, your God. Now do your duty._\n\nUnderstanding this makes Oppenheimer's invocation of the quote make more sense. He's not identifying with Krishna. He's identifying with Arjuna, the one being told that death is going to come to his victims whether he wants them to or not. If anyone is Krishna, it is the bomb itself — the revelation of secret, deadly power that surpasses the individual, and compels them to act.\n\nI have written about this [at some length here](_URL_0_), with other translations (including that of Arthur Ryder, Oppenheimer's Sanskrit teacher) offered up as well."
]
}
|
[] |
[] |
[
[
"http://blog.nuclearsecrecy.com/2015/07/17/now-we-are-all-sons-of-bitches/"
],
[
"http://blog.nuclearsecrecy.com/2014/05/23/oppenheimer-gita/"
]
] |
|
2o0mak
|
If an animal can't see or recognize itself, how does it reproduce with its own kind?
|
Are pheromones that specific and unique that a single animal can differentiate between thousands/millions of others, or is there something else happening?
Ex. Different lizards/fish/birds in similar ecosystem.
|
askscience
|
http://www.reddit.com/r/askscience/comments/2o0mak/if_an_animal_cant_see_or_recognize_itself_how/
|
{
"a_id": [
"cmjsoog",
"cmjzjg4"
],
"score": [
2,
2
],
"text": [
"Animals tend to attempt to reproduce with anything it can, however two different species can't make viable offspring due to many problems which can prevent offspring such as mechanical or being unable to fertilize the egg. however occasionally 2 different species can produce an offspring such as a horse and a donkey make a mule but these offspring are not viable because they can't reproduce.\n\nGenerally speaking though animals of the same species are more attracted to each other like humans are attracted to the opposite gender. Think about why make birds are colorful; to be attractive to females. Although pheromones are a player in this system so are most other sex-derivative traits, and most of the time animals are attracted in someway to their own species socially.",
"You are on the right track when you talk about pheromones, but think of all the senses, not just olfaction (scent). For example, primates are very visually oriented. When they see the face of a primate of the same species, areas of the brain (such as the inferior temporal area which processes information about color and shape from the ventral stream coming from the visual cortex) become highly excited. The best example of this are studies done in monkeys, where another monkey face elicits a strong response. A human face also elicits a response, but not as strongly. That is, the brain is hard-wired to recognize the same species. I do not have time here to go into how all of this takes place, but suffice to say that Futurama was right that science progresses over heaps of dead monkeys.\n\nThis example above only described using visual cues to recognize members of the same species, but most senses have similar bias to recognize members of the same species, and these senses cross talk to help make recognition of members of the same species quite accurate. While it is true that many animals will attempt to mate with other species, it is not as common as you might think."
]
}
|
[] |
[] |
[
[],
[]
] |
|
iguzj
|
What does "chemicals" mean?
|
I always hear about "chemicals" in our food, bodies and environment. What is the definition of chemicals?
|
askscience
|
http://www.reddit.com/r/askscience/comments/iguzj/what_does_chemicals_mean/
|
{
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"c23nbyr",
"c23nfrx",
"c23orci",
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"score": [
5,
4,
2,
2
],
"text": [
"In this case, the Wikipedia article works best:\n\n_URL_0_\n\nIn short, just about everything. Water is a chemical for example.",
"When you hear about \"'chemicals' in our food, bodies, and environment,\" it's likely the person is talking specifically about A) synthetic chemicals, B) refined and semi-synthetic petroleum products and other natural derivatives, C) biologics such as hormones, antibiotics, and the like, D) or all of the above. Among others.\n\nFood itself is chemistry. The energy contained within the high-energy bonds in carbohydrates, fats, and proteins is used to power all your biological processes. The skeletons of those molecules can also be used as building blocks for processes that create new structures. It's all just chemistry. And cooking is applied chemistry. (Cf Nathan Myhrvold's _Modernist Cuisine_ and the entire field of molecular gastronomy.)\n\nThough a lot of the stuff from the first paragraph arguably does not belong in our food.",
"Nothing, absolutely nothing. The more you know about chemistry, the less it means. \n\n",
"It means - **Be afraid!!**\n\nWhat it should mean - Oh, just [everything](_URL_0_) really."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Chemical_substance"
],
[],
[],
[
"http://en.wikipedia.org/wiki/Chemical_substance#Definition"
]
] |
|
4ja4oc
|
How much can I trust Albert Speer's memoir: Inside the Third Reich?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4ja4oc/how_much_can_i_trust_albert_speers_memoir_inside/
|
{
"a_id": [
"d35aw9m"
],
"score": [
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],
"text": [
"The main problems for Speer's memoirs, both *Inside the Third Reich* and the *Spandau Diaries* are two-fold. Firstly, part of the appeal of Speer's postwar writings was that as an insider, he gives a portrait of the Third Reich's leadership and it is often an unflattering picture. Speer spends a good deal of time in his postwar writings describing the personal foibles and character flaws of figures like Goering and Himmler as corrupt and incompetent. Speer portrayed Hitler as a magnetic enigma and one whose charisma masked his demonic tendencies. This is not to say that these historical portraits are manufactured or completely inaccurate, but they often served a narrative function of embellishing Speer's self-constructed image as a seduced and fundamentally naive figure. These unflattering portraits of the NSDAP elite have unfortunate implications, especially within the German middle class social milieu in which a fundamental lack of culture and education, as well as parvenu pretensions, is a somewhat damning *faux pas*. \n\nThe second factor undermining the veracity of Speer's postwar writings is that he was incredibly selective about how he portrayed the Nazi period and his role in it. Speer did a good deal of researching his memoirs was done via the *Bundesarchiv* in Koblenz and the archivists there do not recall him asking for materials on either forced labor or the Holocaust. Bombing had destroyed a good deal of the Armaments Ministry's own archives, so Speer often had a good deal of wiggle-room with which to portray his efforts in the most flattering light as possible. He portrayed himself as an apolitical figure whose main flaw was loyalty, which led to Speer embellishing his connections to the 20 July plot and even a claim he planned to kill Hitler in 1945, of which it the only evidence is Speer's word for it. The two main assistants for his memoirs, were journalists Joachim Fest and Wolf Jobst Siedler, men who had knowledge of the Third Reich, but were not trained historians. Neither they, nor their own research assistants, visited Koblenz to check the veracity of Speer's account, nor did they consult historians (Fest's view of the profession was rather dismissive). Siedler and Fest did interview some parties who were witnesses to the events Speer described, such as Milch, but many of these contemporaries of Speer were just as interested in a postwar exoneration as Speer. More disturbingly, Siedler and Fest also consulted David Irving on various points. Although Irving had yet to write his \"opus\" *Hitler's War*, it is a considerable red flag and his dalliances with Holocaust denialism has colored his earlier works on Milch and Dresden.\n\nWhile Speer's lively and intimate style might enchant lay readers, the omissions and pattern of blame-shifting is rather obvious to those aware of the voluminous historiography on the Third Reich. In his review of the memoirs, the historian Golo Mann noted that Speer's direct references to the Holocaust were often quite facile and a kind of weak exculpatory. Reviews by other German historians were likewise troubled by Speer's selectivity and weak admissions of guilt. What would have been even more damning for the likes of Mann was that subsequent research into Speer\nand the Armaments Ministry has shown him deeply involved in issues of forced labor and aware of the exploitation and murder of the Jews. Speer relied upon an edited version of the War Ministry's Chronicle maintained by his colleague Rudolf Wolters, which he subsequently donated to the *Bundesarchiv*. Nor has Speer's reputation as a miracle worker in armament's production fared very well in the historiography produced since 1970. Both Adam Tooze and R. J. Overy have shown that Speer's achievements were more apparent than real, and these findings have also been largely confirmed by the Bundeswehr's *Militärgeschichtliches Forschungsamt*'s official history of the Second World War. \n\nSo Speer's various writings are valuable in that they preserve a specific *type* of postwar self-fashioning of the past. The success of Speer's memoirs in the West German readership resonated with a wide swath of the population in that it was an incredibly comforting vision of a disturbing past. Speer's exculpatory picture acknowledged the crimes of the Third Reich, but in a manner that did not command a great deal of self-reflection or recrimination. To be seduced by evil is a much safer narrative of the past than to be a collaborator, or worse, a beneficiary of Hitler.\n\nSo in short, how much should you trust Speer's *Inside the Third Reich*? About as far as you can throw it. \n"
]
}
|
[] |
[] |
[
[]
] |
||
1qut48
|
out of all the words in the world, why did we end up with limited surnames?
|
There's close to infinite words in the world, but why are our surnames so limited? Where did these names come from?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1qut48/out_of_all_the_words_in_the_world_why_did_we_end/
|
{
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"cdgpvgs"
],
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"text": [
"*Western* surnames are limited because we have what's called 'Patrilineal' naming. You take your fathers surname, exactly as he has it. New surnames only pop up through people deliberately changing their name or mistakes *but* they can die out when the male line ends (or things like children taking their single mothers maiden name)\n\nOther countries have 'Patronymic' naming, where the surname *references* the father in some way but doesn't copy it exactly.\n\nFor example in Iceland it's common practice for your surname to be your father's first name + your gender. So a family tree could be ;\n\nJon Johan - > Henning Jonsson - > Olaf Henningsson. \n\n(The female equivalent being *Henningsdotter*)\n\nOr if you take **Poland** where sometimes they'll take the fathers surname *or* occupation and add '*ski*' (or some variant) to the end which translates to '*Son Of*' / '*Daughter Of*' essentially. The same family tree could be ;\n\nJon Johan - > Henning Johanski - > Olaf Kowalski (Kowal means 'Smith' as in a Blacksmith)\n\nLots of countries have variations on the same theme. Your name isn't necessarily the same name your father had so this leads to very confusing family trees but also the potential for new surnames popping up all the time.\n\nIt used to be fairly common in western, English speaking countries too. There was a hint in that last example. Some people have the surname 'Smith', or 'Carpenter', 'Fischer', 'Archer', 'Bishop' and so on. \n\nI *think* the practice is slowly dying out though, my conclusion is because of city living and the invention of craploads of terrible job titles. Nobody wants their kid to be called *John OfChicago* or *Sarah RegionalSalesManager*.\n"
]
}
|
[] |
[] |
[
[]
] |
|
39qpc1
|
How do calculators compute factorials for non-integer numbers?
|
Just recently I read that as a result of generalizing the factorial function using the gamma function, the factorial (-1/2)! is equal to sqrt(pi). I thought this was incredibly interesting, so I punched sqrt(pi) and (-1/2)! into my calculator to check it out and saw that they were in fact equivalent. Immediately, I wondered how my calculator had computed (-1/2)!.
The gamma function is clearly difficult to evaluate, being defined as the [improper integral linked to here.](_URL_0_) So how is this done with calculators? Is there some kind of algorithm that calculators use to compute factorials for non-integers? If so, I'd be interested in hearing/reading about it, how it works, and how it was derived.
Edit: I kind of wish I could categorize this post as both computing/mathematics. If you think I should change it, I'd be more than willing to.
|
askscience
|
http://www.reddit.com/r/askscience/comments/39qpc1/how_do_calculators_compute_factorials_for/
|
{
"a_id": [
"cs5km04",
"cs5n0p4"
],
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8,
2
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"text": [
"There are a number of approximations of factorials (and, by extension, the Gamma function) of the form\n\n*n*! ≈ *n*^*n* e^(–*n*) *p*(*n*)\n\nwhere *p* is at most a polynomial in *n*. The most well-known isn [Stirling's approximation](_URL_0_), but from what I understand, the Gamma function is typically evaluated using the [Lanczos approximation](_URL_1_), which has the same basic form but can be made to converge faster.",
"Go get a copy of 'Numerical recipes in C' (or basic, fortran etc.) They give a few chapters an how special functions are evaluated, meaning how you break it down to arithmetic computers can do fast"
]
}
|
[] |
[
"http://d3k4erco76x75g.cloudfront.net/wp-content/uploads/2012/08/gamma-function.png"
] |
[
[
"http://www.wikiwand.com/en/Stirling's_approximation",
"http://www.wikiwand.com/en/Lanczos_approximation"
],
[]
] |
|
2frrr0
|
why is "bloody" a bad word for the britisher types? nsfw ? (not my work)
|
Why is "bloody" a bad word in the U.K.? I don't really know, but it seems to get censored like "fuck" does here in the U.S., right? What does it really mean even? Just "covered in blood"? What's so bad about that?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2frrr0/eli5_why_is_bloody_a_bad_word_for_the_britisher/
|
{
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"ckc4gdk",
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"ckcc52m",
"ckccdx1"
],
"score": [
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9,
5,
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2,
2,
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2,
2
],
"text": [
"It's not that bad of a word and I've never seen it censored on British television. ",
"As an Australian, bloody can be used in the same way that \"fucking\" can be. Eg. My bloody golf club is bent.\n\nI've never seen in censored, but I remember that in school it was considered a curse word since that is how we used it.",
"Bloody = 'Fucking' lite here in the UK.\n\n",
"Nobody is completely sure.\n\n\n_URL_0_",
"\"Bloody\" isn't that severe. It's more like \"damn\".",
"bloody = damn. not a very bad word and is defo not considered a swear words. ",
"it gets censored in the UK?",
"In all my 20 years of living in the UK I have never once experienced 'bloody' being censored. Hell even Ron in Harry Potter says bloody hell. ",
"\"Bloody\" isn't censored in the UK or Ireland. It's a soft swearword, much like \"damn\" or \"feck\". \n\nSource: Irishman who gets English telly and has been there a good few times."
]
}
|
[] |
[] |
[
[],
[],
[],
[
"http://en.m.wikipedia.org/wiki/Bloody#Etymology"
],
[],
[],
[],
[],
[]
] |
|
437o4k
|
why do pixels warp when viewed through a camera, and is it similar to this effect?
|
Why do pixels warp when viewed through a camera? And is it the same effect that caused [this?](_URL_0_)
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/437o4k/eli5_why_do_pixels_warp_when_viewed_through_a/
|
{
"a_id": [
"czg4umn"
],
"score": [
4
],
"text": [
"I think what you're looking for is called a [Moire pattern](_URL_0_)."
]
}
|
[] |
[
"https://gfycat.com/EvergreenEnlightenedAltiplanochinchillamouse"
] |
[
[
"https://en.wikipedia.org/wiki/Moir%C3%A9_pattern"
]
] |
|
2imabz
|
why do we have a "second stomach" for desert?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2imabz/eli5_why_do_we_have_a_second_stomach_for_desert/
|
{
"a_id": [
"cl3dyx6",
"cl3e2xm"
],
"score": [
2,
5
],
"text": [
"That is an entirely learned behavior, usually from always eating sweet desserts after dinner. ",
"the desert is hot and the heat causes you to gain a second stomach in an attempt to preserve itself (think camels). The organs then allows the esophagus to split in two through a process called eosinophilic esophagitis. Its quite a remarkable process that happens when the temperature spikes at 120. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
1gr53x
|
can anyone explain this math question to me?
|
"Ishaan had to read articles 27 through 53 for homework tonight.
If Ishaan read all of the articles he was assigned, how many articles did he read?"
I can't wrap my head around this problem, my knee-jerk reaction was of course to subtract 27 from 53 which gives me 26 but the answer is 27. I just can't understand why, shouldn't this be the right way to think about this?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1gr53x/eli5_can_anyone_explain_this_math_question_to_me/
|
{
"a_id": [
"camyecf",
"camyf60",
"camyf6c",
"camz5hp",
"camzfo8",
"can564k",
"canb2hd"
],
"score": [
7,
6,
11,
5,
2,
3,
2
],
"text": [
"Because he read the 27th article too. Say out loud every article he read. For every article you say, make a check mark on a piece of paper. You will have 27 check marks at the end.\nHe read 27, 28, 29, 30.... All the way to 53.",
"The problem is how language works. WHen you say A through B you mean A, all the ones up until B, **and also B**. Doing subtraction only tells you how many are between A and B, which will always be one less that the 27 through 53 phrasing.\n\nThe problem is that phrasing isn't really clear. Normally if someone wanted to be clear they would say 27 through 53 **inclusive** which means \"I want to count the ones on the end as well. But you're interpreting it as 27 up until but not including 53.",
"well, he read #s\n27\n\n28\n\n29\n\n30\n\n31\n\n32\n\n33\n\n34\n\n35\n\n36\n\n37\n\n38\n\n39\n\n40\n\n41\n\n42\n\n43\n\n44\n\n45\n\n46\n\n47\n\n48\n\n49\n\n50\n\n51\n\n52\n\n53\n\nwhen just subtracting 27 from 53 you're fiding the difference in the number, but you're not taking in to account the starting point, #27, which was read as well.",
"Don't feel too 5 about it, this is a common source of off-by-one errors even among professional math types (source: IAm1). \n\nJust think of a simpler case: if you read articles 5 through 6, how many have you read? Cos it ain't 6 minus 5...",
"It is like saying he read articles 1 to 2, if you make:\n2-1 = 1\n\nif you take the difference between the article you are treating them has numbers, when they are objects tagged with numbers.",
"In math, this is generally known as the \"fence post problem\". Here's a good, clear article on it: _URL_0_",
"Another way to look at this. He had to read 53 articles and he skipped the first 26 articles so he read 53-26 = 27 articles."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[
"http://betterexplained.com/articles/learning-how-to-count-avoiding-the-fencepost-problem/"
],
[]
] |
|
1z5dlb
|
how is it that we have a nearly universally accepted calendar?
|
Or do different countries use different calendars? As far as I know, we all use the Gregorian calendar outside of the exceptions of certain Orthodoxies and the Islamic and Fiscal calendars.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1z5dlb/eli5how_is_it_that_we_have_a_nearly_universally/
|
{
"a_id": [
"cfqo3pt"
],
"score": [
3
],
"text": [
"Because the west won. The west (meaning Europe and North America) ruled the world since the 1800s and imposed their calendar on everyone else. The calendar had been pretty standard for about 500 years at that point in the west already , and now everyone else who was using different calendars were forced to change to the western system. "
]
}
|
[] |
[] |
[
[]
] |
|
25ylow
|
Why is the structure of the universe so similar to the way neurons are connected?
|
[Large scale structure of the universe](_URL_1_)
[Neurons](_URL_0_)
|
askscience
|
http://www.reddit.com/r/askscience/comments/25ylow/why_is_the_structure_of_the_universe_so_similar/
|
{
"a_id": [
"chlybsa"
],
"score": [
17
],
"text": [
"There is a superficial resemblance, but no underlying connection. Many processes can result in a filamentary structure. Beyond that, there is no similarity between the two structures you showt."
]
}
|
[] |
[
"http://dejavouz.files.wordpress.com/2009/03/neuronsk.jpg",
"http://scienceblogs.com/startswithabang/files/2011/03/cosmic_web_3.jpeg"
] |
[
[]
] |
|
7zbsnh
|
if warm light is better for the eyes at night, why are most new led streetlights a bright white color as opposed the orange sodium lights?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7zbsnh/eli5_if_warm_light_is_better_for_the_eyes_at/
|
{
"a_id": [
"dumv4r6",
"dumvjlo"
],
"score": [
2,
3
],
"text": [
"I’d assume because maybe it’s brighter than warm lights, and that’s a safety concern to consider. Plus the bright lights help put out the light that can help keep you awake, maybe it serves a double purpose to prevent falling asleep at the wheel?\n\nMore than likely it’s just for the brightness now that i think about it.",
"The new LED lights that have appeared in the past few months are bright, and they’re white, but the color temperature is a warmer, more neutral white, rather than a harsh, almost blue-white that I think you are describing. The light that Is first mentioned yields far better color rendition, meaning that colors appear to the human eye to be far closer to how they would look in daylight than in the harsh orange glare of a sodium light. \n\nEven if the lights you are asking about are that almost blue-white that is described above, the color rendition would be **far** better than sodium lights. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
3mhwul
|
the fair repair bill in ny and why it is necessary to keep phone repair legal
|
It is known as S3998 in the State Senate and A6068 in the State Assembly.
[This](_URL_0_) and [this](_URL_1_)
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3mhwul/eli5_the_fair_repair_bill_in_ny_and_why_it_is/
|
{
"a_id": [
"cvf6nam",
"cvf9aed"
],
"score": [
11,
29
],
"text": [
"Why do they need a bill to make it legal. It's my damn phone and I can do whatever I want with it. What is Google or Apple gonna do if I repair it or modify it?",
"I'm a repair tech, I'll try to explain this as best as I can. So basically the bill would require big companies to provide all the information about their products to the public. To me personally, this is important because it would force these companies to release their mainboard schematics (ELI5: what all those little components do on the mainboard and how to purchase replacements). This means if something on the mainboard shorts out, I can find it, use the schematic to figure out what that part does, order a replacement part, and replace it via microsoldering. The other point of the bill is to keep big companies from having a monopoly on repairing their own devices. Think about it this way - If you broke your phone screen, wouldn't it suck if the only way to fix it would be to go through Apple, having to pay $300? \n"
]
}
|
[] |
[
"http://assembly.state.ny.us/leg/?term=2015&bn=S03998",
"http://assembly.state.ny.us/leg/?default_fld=&bn=A06068&term=2015&Summary=Y&Actions=Y&Text=Y&Votes=Y"
] |
[
[],
[]
] |
|
776g44
|
How well stocked were Soviet grocery stores?
|
I always see on Reddit these anecdotes about Russians/other Soviet citizens coming to the USA and being shocked by the abundance in our stores. How true is this? If it is true, why?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/776g44/how_well_stocked_were_soviet_grocery_stores/
|
{
"a_id": [
"dojgucu"
],
"score": [
12
],
"text": [
"Side question: Did the Soviet Union *have* grocery stores? Where did a regular person go to get their food for the day?"
]
}
|
[] |
[] |
[
[]
] |
|
5e73nd
|
why do bands bring have their own speakers and amplifiers if everything is just run through the arena's pa system?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5e73nd/eli5_why_do_bands_bring_have_their_own_speakers/
|
{
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"daac0it",
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3,
3,
11
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"text": [
"Like their guitar amps and stuff? A guitar amp does a whole lot more to influence the actual sound and tone than the PA. A guitarist's amp is pretty integral to his whole sound, so he'll want it to be consistent, and he'll want control over it. Then the venue will put a mic on his amp to connect it to the PA.",
"Recorded an album before and performed at a few clubs. It works like this,\n\nYour Amps, you pre-Amps, your Guitar, your EQ's that is **your** sound, speaker included. When in a studio or performing, your shit goes up, and then they place a mic in front of the speaker or inside the drum and so on to capture your sound.\n\nIf you take away that Marshall Tube on the 1/2 stack out of the equation, you will be hearing something totally different at this point and as slash pointed out, the musician wants 100% control of his sound while performing.\n",
"there's also a monitor on stage so the band can hear themselves; a PA system won't do that particularly well since sound bounces and gets overlaid with crowd noises and such. I've played in a few venues that were so loud I couldn't hear the guy right beside me, so relying on the PA system meant the guy three people down is half a beat behind. All that stuff on stage is necessary for the band to sound like they do and to be able to hear themselves.",
"The speakers on stage are band's personal amplifiers. These have a unique sound that are a band's tone. Depending on the venue these will be far too small to adequately fill the room.\n\nThe crew and audio engineer place microphones on these amplifiers to capture the band's unique sound and make it loud enough for everyone to hear.\n\nIn smaller venues the sound of the guitar and bass guitar are typically only coming from the amplifiers on stage.",
"I'm a stage hand and although the venues I work at have PA systems, they don't use them for concerts. We will set the house PA up for graduations, and business conferences but when the big bands roll through they bring their own audio gear. Usually there is one 54' semi trailer for audio, though I've done bands with up to three. The riggers will lift chains up to attach to the beams at the top of the stage and chain hoists will suspend [the large arrays](_URL_6_) of speakers. We set up [stacks of subs](_URL_0_) on the floor or sides of the stage. \n\nOn the front of the stage we often set up smaller main speakers for the part of the audience that is too close to be in the direct line of the arrays. Most often they are just a smaller version of the large line array speakers that are hanging. Also on the front of the stage, but facing away from the audience we set up [monitors](_URL_4_) so the band members can hear the necessary bits of the song to stay in time. Sometimes listening to the monitors sounds quite different from what the audience is hearing since it's often only two or three instruments and not the whole ensemble. \n\nBehind the band are [the amps](_URL_1_) each with a mic positioned in front. Many bands will use a particular amp for one song to get a special sound out of it, and the rest of the show that amp is just a decoration. So it's not uncommon for a band to have an unusual assortment of amps on stage from vintage to the latest in technology. Sometimes bands [have been caught](_URL_5_) with entirely fake amps that are only decoration. Here's a shocker, I've seen a whole lot of bands do this so it's not really a scandal when a band is called out. What is a scandal is when a stagehand posts a photo of behind stage to social media. It's grounds for termination.\n\nControlling everything is typically two stations for processing the audio. On the side of the stage is your [monitor mix](_URL_7_) station. The roadie here makes sure the band members have clear sound directed back to them with no feedback so they can play in time with each other. Also this is where you will see the large paddles in the air which are [antennas](_URL_3_) for the wireless mics. Then out in the middle of the arena is the Front of House [audio station](_URL_8_), usually right next to the [lighting console](_URL_2_). \n\nJust about everything is digital now, so the signal coming from the mics are digitized into the sound console at the monitor mix station and is sent to the front of house using special Cat6 cable called Ethercon for its heavy duty shielding upgrade. It's so much nicer running a single lightweight cable out to front of house compared to the older methods of heavy audio snakes. It still takes a whole lot of power to drive the speakers though, so there are plenty of heavy cables to run.\n\nWorking as a stage hand is a ton of fun, but it's a whole lot of heavy labor. There are a lot of hidden hazards, so many crew members have scars from past injuries. You don't always get to see the concert either, so that can suck. I normally run a camera during the show so I usually have the best spot in the house. The signal from the camera goes to a switcher where a 'technical director' chooses the best shot and puts it on the screen so the people in nose bleed seats can see who's playing up on that stage up there. My favorite position is in between the crowd barrier and the stage so I can walk back and forth across the front and get extreme close ups of the performers. They will usually play for the camera so they are looking right at you and it's like a one on one rock star experience. This is so much better than front row tickets and I make bank running camera. "
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[
"http://www.proaudio-central.com/thumbs/1020x768r/2016-02/outline-dbs-18-2-subs-in-use-at-the-experience.jpg",
"http://cdn.mos.musicradar.com/images/magblogs/guitarist/Images/gear%20tips%20and%20advice/micing_amps_three-650-80.jpg",
"https://66.media.tumblr.com/95530409a8c748ed9d1a535e7cee09f8/tumblr_mr4ju9KhPT1s5rnofo1_1280.jpg",
"http://shureblog.co.uk/content/uploads/2015/04/antenna-closer-better.jpg",
"http://us.123rf.com/450wm/mimagephotography/mimagephotography1504/mimagephotography150400153/38776502-on-stage-before-music-festival-black-speaker-monitors.jpg",
"http://www.metalsucks.net/wp-content/uploads/2013/07/Black-Veil-Brides-fake-cabs.jpg",
"https://en.wikipedia.org/wiki/Line_array#/media/File:JBL_VerTec_line_arrays_(4889_x_9_%26_4880a_subs_x_4\\).jpg",
"https://eemixer.files.wordpress.com/2008/10/img_0293a.jpg",
"http://media.gettyimages.com/photos/front-of-house-at-the-megadeth-and-slayer-concert-at-the-festival-on-picture-id97404593"
]
] |
|
12xtz9
|
Do extension cords lose power?
|
If you had 5 extension cords attached to each other and a phone charger at the end, would it charge equally as fast as one with only 2 extension cords? If not, would the difference be note worthy? Would having something else plugged into the other outlet change any of this?
|
askscience
|
http://www.reddit.com/r/askscience/comments/12xtz9/do_extension_cords_lose_power/
|
{
"a_id": [
"c6z1mtz",
"c6z1nsj"
],
"score": [
2,
3
],
"text": [
"There will always be some loss, whether or not you can actually notice depends on what you're trying to run.\n\nIf all you're powering is a phone charger, as long as you use some sane number of cords you won't notice a difference in charge times. Each cord will dissipate some power as heat but you're not coming anywhere near the maximum power draw from the outlet so it's all fine.\n\nIf you're powering something like a washing machine that little bit of extra power burned up by the cords could potentially push the outlet over it's limit and trip a breaker.\n\nThere are ancillary effects but I can't think of any that would affect something low-power. You'd basically be running slightly less efficient than normal and shouldn't see radical differences unless the equipment demands high power or is especially sensitive to voltage/current fluctuations.",
"There will be negligible ohmic heating loss in the cords, but it will not affect the charging time. The phone charger uses a switching AC to DC power converter that will draw as much power as it needs to output the correct amount."
]
}
|
[] |
[] |
[
[],
[]
] |
|
f973x4
|
what is upregulation of dopamine receptors?
|
I read this from this article - _URL_0_
'In rats, treadmill running increases the release of dopamine and upregulates the number of dopamine receptors in the reward areas of the brains'
What does 'upregulates the number of dopamine receptors' mean?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/f973x4/eli5_what_is_upregulation_of_dopamine_receptors/
|
{
"a_id": [
"fipvqnt"
],
"score": [
2
],
"text": [
"It means the number of dopamine receptors on each cell is increased in those areas. If there are more receptors, then more of the dopamine \"signal\" can enter the cells.\nImagine a line of people having tennis balls thrown at them. Each person has to catch as many tennis balls as possible and place them in a bucket - the number in the buckets at the end is the total \"signal\". There will be a point where increasing the number of balls being thrown won't increase the number of balls in the bucket - there are just too many to catch. If instead you increase the number of people catching, then the number in the bucket will go up. The people catching are the receptors and the balls are the dopamine molecules."
]
}
|
[] |
[
"https://www.healthline.com/nutrition/how-to-increase-dopamine"
] |
[
[]
] |
|
1rtla2
|
Throughout the history of Islam, were there any popular heretical movements? If so, how were they dealt with?
|
When I say heretical, I mean something like a person convincing people he's Muhammad reincarnated. Or someone to Islam as Arius was to Christianity.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1rtla2/throughout_the_history_of_islam_were_there_any/
|
{
"a_id": [
"cdqrs2m",
"cdqvucr"
],
"score": [
2,
2
],
"text": [
"No one has claimed he's Muhammad reincarnated, but there of course have been many sects and heretical movements. Here are some of the more important ones:\n\n* Alawites - In Syria, Assad's sect\n\n* Alevi\n\n* Druze\n\n* Ahmadiyya - the founder Ahmad claimed to be the Messiah and a prophet \"subordinate\" to Muhammad\n\n* Bahá'í - usually considered a standalone religion\n\n",
"There were plenty of smaller deviant groups that one could call stereotypical heretics in the vein of the Cathars, although they were mostly short-lived. A particuliarly famous group were the Qarmatians who sacked Mecca in order to bring around the end of the world.\n\nFirst, Islam's divided into two main groups, the Sunni and the Shi'a (there's the Ibadi in Yemen as well, but they're a small group). They don't like each-other much, which is a significant facto in Middle-Eastern politics to this day.\n\nAn important aspect of Islam is that it's a very legal religion; there are a lot of subdivisions that differ regarding jurisprudence and interpretation of Shari'a. Most of the times they're not something to execute someone over. Shi'a Islam is a tad more intricate by having divisions based on the amount of Imams they consider to be legal; they're called 'Fivers', 'Seveners' and so on.\n\nSunni Islam has a few legal traditions that are bit less tolerant of others, including the Salafi and the Wahhabi. They have a more violent rhetoric towards other Muslims (and non-Muslims), but they're not necessarily considered heretics themselves by others. Although, of course, that depends on the school of jurisprudence.\n\n'Convincing people he's Muhammad' wasn't necessary, since Islam had its own idea of a Messiah, the Mahdi (who has ties with the aforementioned Imams), who is a successor of Muhammad. Throught history many have claimed to be the Mahdi, and some of those have been very succesfull. Wikipedia has a nice page on Mahdi-claimants, I believe.\n\nIslam is very pluriformous; I haven't even mentioned the Sufi yet, or the many off-shoots that have become like religions on themselves. Who's a 'heretic' and who is not varies from tradition to tradition, legal school to legal school."
]
}
|
[] |
[] |
[
[],
[]
] |
|
iaf8f
|
Why not give your child peanut butter until after the age 2?
|
Apparently this is the standard rule according to my wife. Of course her mom my son peanut butter a few months ago and said she didn't know she shouldn't (She's a nurse and has a 7 year old). So my wife today tries to give my son peanut butter and now his cheeks have broken out with a rash.
My son is 20 months old, but what I want to know is, is there any science behind this idea? Does waiting until later improve the chances of not having an allergy? Would the earlier feeding have impacted the chances of the allergy?
Thanks
|
askscience
|
http://www.reddit.com/r/askscience/comments/iaf8f/why_not_give_your_child_peanut_butter_until_after/
|
{
"a_id": [
"c2270wv",
"c227ull"
],
"score": [
9,
9
],
"text": [
"According to this [2008 study](_URL_0_) of children in England and Israel, the prevalence of peanut allergies in England was 10x higher (within the study group), and they attributed that to the first age of introduction to peanuts.\n\n > We demonstrate that Jewish children in the UK have a prevalence of PA that is 10-fold higher than that of Jewish children in Israel. This difference is not accounted for by differences in atopy, social class, genetic background, or peanut allergenicity. Israeli infants consume peanut in high quantities in the first year of life, whereas UK infants avoid peanuts. These findings raise the question of whether early introduction of peanut during infancy, rather than avoidance, will prevent the development of PA.",
"from what my doctor told me, you wait till two years old so that they can effectively communicate with you that they can't breathe after eating the peanuts. It wasn't about exposure to the peanut, but communcating that he/she is having a reaction to the peanuts"
]
}
|
[] |
[] |
[
[
"http://www.ncbi.nlm.nih.gov/pubmed/19000582"
],
[]
] |
|
4b3plz
|
are lawsuits against big companies that end with the plaintaint receiving the money back for what he paid his lawyer a waste of time?
|
Like he pays the lawyer $300 000 for the duration of the trial, and he getd paid by that big company $300 000 which is nothing for them.
Is it a waste of time for everyone in the court, except the lawyers who win ofc.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4b3plz/eli5_are_lawsuits_against_big_companies_that_end/
|
{
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"d15s6jt",
"d15sbsg",
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],
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4,
7,
2
],
"text": [
"2 things, when a plaintiff wins a case, the defendant might have to pay the plaintiffs legal fees as part of a decision, in addition to other damages. \n\nand secondly, yes, it is a waste of time and resources. its almost always in everyones best interest to settle cases outside of court. both tge defendant and plaintiff pay fewer legal fees, the plaintiff is guaranteed a pay check, the plaintiff saves themself the risk of losing and paying way more, and even the lawyers like it because they get a quick paycheck. ",
"No, what makes you say that? The loser has to pay a large sum, and more importantly, they will be ordered to stop what they were doing wrong. The most important civil cases are not about big payouts, but about getting a party to stop some form of harmful conduct. In a trespass case, it's more important to you that you get a squatter of your house than that they pay you damages. If the government is violating your rights, you want them to adhere to the Constitution and not just buy you off.\n\nMany major figures and businesses carry insurance that helps to pay their legal fees, so they get to keep a much greater part of damages they are awarded. Punitive damages are often scaled to the size of the loser, so that they may be much higher than the actual damages. In some cases the loser has to pay the legal fees of the victor, and this is also a common aspect of settlements.",
"* lawyers for individuals who sue big companies often work on a contingency basis...they get a fix percentage of the settlement, which means sometimes they get nothing\n* legal fees are often awarded tot he plaintiff, especially if it appears the defended was trying to make it unaffordable for them to sue\n* at the end of the day, the law doesn't care how much you pay your lawyer...they award damages, and the rest is between you two"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
fokr7w
|
Did the Spanish Flu affect any sporting events at the time?
|
The Tokyo Olympics scheduled for later this year have been postponed until the next year. This in mind, did anything similar happen when the Spanish Flu was ongoing?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/fokr7w/did_the_spanish_flu_affect_any_sporting_events_at/
|
{
"a_id": [
"flgnelk"
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],
"text": [
"It actually saw the Stanley Cup final cancelled for the first time (the second would be in 2005 due to a labour stoppage; 2020 may also be cancelled, we'll see).\n\nIn 1919 there were two major professional hockey leagues: the NHL (National Hockey League; which had teams in Montreal, Ottawa, and Toronto), and the PCHA (Pacific Coast Hockey Association; teams in Vancouver, Victoria, and Seattle). Similar to baseball, the champions of each league would play each other in a series to determine who won the Stanley Cup, with the host alternating years (even was the NHL, odd was PCHA). In 1919 the Montreal Canadiens won the NHL title, while the Seattle Metropolitans won the PCHA, and Montreal went west to play Seattle.\n\nThe series was a best-of-five, meaning a team had to win three of the five games. As the leagues also had slightly different rules (the most notable being the PCHA had an extra player on the ice), games alternated between NHA and PCHA rules. Seattle won the first and third game, while Montreal won the second, while game four was tied 0-0, and 20 minutes of overtime failed to see any goals. With players exhausted, it was called off. There was discussion of how to play game five, and it was resolved they would play that game, and any future ones, until a winner was declared. Montreal won in overtime, tying the series at two wins, two losses, and a tie for each. This was on March 29, and a game six was scheduled for April 1.\n\nHowever in the days before game six, several Montreal players took ill with the influenza going around. Five of them ended up in the hospital, and as the Canadiens only had 13 players on the roster, that was a considerable number. They waited to see if things would improve, but decided only five hours before game six to cancel the match. Montreal offered to forfeit the Stanley Cup as a result, but this was declined by Seattle, who didn't want to accept it under the circumstances. Montreal then asked if they could use players from the Victoria team (a not-uncommon practice of the era, when players would occasionally be loaned for a game or two; but never five at once), but the PCHA president refused this request. So on April 2 the series was cancelled, and for the fist time since the Stanley Cup was introduced in 1893, no winner was declared (as noted this would not happen again until 2005). Traditionally the winning team had it's name and those of the players engraved on the Cup, but for this series it simply says: \n\n\"1919\nMontreal Canadiens\n\nSeattle Metropolitans\n\nSeries Not Completed\"\n\nA further note: four of the Canadiens players recovered from the flue and continued their career. But one did not: \"Bad\" Joe Hall, a notorious tough player who had been highly regarded during his 17-year career. He was 37, old for a hockey player at the time, and his symptoms worsened, and on April 5 he died. He was the only hockey player to die of the influenza, though Canadiens manager George Kennedy would die in in 1921 of health complications related to it."
]
}
|
[] |
[] |
[
[]
] |
|
1z1hl6
|
why is green required to do cgi?
|
Why is the colour green need to be used on everything that is to be altered with CGI?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1z1hl6/eli5_why_is_green_required_to_do_cgi/
|
{
"a_id": [
"cfpncl0",
"cfpnpsx"
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3,
3
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"text": [
"It doesn't have to be green. Green is just commonly used because it provides a high contrast with the colors normally found on people.\n\n[Sometimes, people end up wearing green...](_URL_0_).",
" > Why is green required to do CGI?\n\nIt isn't. The technique being used is called [chroma key](_URL_0_), and all it needs is a solid color that isn't found anywhere else in the scene. For most of the technique's history, the color of choice was *blue*, not green. If you watch an older movie, you can often see fringes of blue around actors (especially if there's frizzy hair or fuzzy clothing) during special-effects-heavy scenes because of incomplete chroma keying.\n\nBut with the advent of digital recording, green has become more popular. This is because digital cameras are designed to mimic human eyesight in terms of being more sensitive to green. This means that you can use chroma key on a green background with less illumination.\n\nThere's also the side effect that green doesn't conflict with blue eyes, or blue jeans."
]
}
|
[] |
[] |
[
[
"http://www.youtube.com/watch?v=PKRSyjMOORU"
],
[
"http://en.wikipedia.org/wiki/Chroma_key"
]
] |
|
c81lbp
|
How and when did acting become a reputable profession?
|
In contemporary Western culture, actors are considered some of the most prestigious members of society, probably along the same level of repute as elite businesspeople or politicians, and just below classical musicians and processors.
Yet a couple hundred years ago this wasn't true at all. In Shakespeare's London, the theater was considered to be pretty populist and low-class. Sure he might have performed for the Queen, but his plays were also popular entertainment. The Globe Theater was also, from what I understand, in a pretty dodgy neighborhood filled with brothels. Meanwhile in Italy, there was apparently significant crossover between commedia dell'arte actors and prostitutes. In parts of the Middle East until very recent times, female performers were universally associated with prostitutes and considered incredibly shameful.
So when was the theater elevated as an art form that could not only be appreciated by members of the upper class, but also be performed by this class? I get the impression that by the late 1800s, acting in England was considered to be pretty high-brow. However, the description of Thespians in The Portrait of Dorian Gray suggests that by 1890, theater was still associated with vice and abjection at least among snobs such as the title character.
I get the impression that this transition predates film and television. So what, if not technology, precipitated this pretty serious change in reputation?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/c81lbp/how_and_when_did_acting_become_a_reputable/
|
{
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"esqhpwe"
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"text": [
"Great question! So let's begin with your initial paradigm that actors (and I'm using the term \"actor\" as inclusive of all gendered theatre performers) were often considered sex workers (a term I’m going to use rather than “prostitutes”). You're absolutely correct, but we'll have to set up the social, classed framework within which this has been the case in Euro-centric history. Then, we can examine the changing socio-economic structures that began in the 18th century as a parallel to the shifting perception of actors as sex workers. Although, I'll add that the private sex lives and relationships of even the most well-respected actors today are still perceived and sold as publicly visible/available amusement.\n\nSo, what’s the correlation between sex work and acting? The answer is that it’s as old as Euro-American theatre itself. There are no examples of women as actors in the earliest days of Athenian-Greek theatre in the 5thcentury BCE, but by the end of the century (especially with the advent of Greek New Comedy) there are increasing representations of female sex workers as characters in many plays. Menander, Terence, and Plautus were comic playwrights that included female sex worker characters in their plays. But by the 3rd and 2ndcenturies BCE, there is evidence that women were acting in roles on the stages of theatres around the Mediterranean—especially in a type of performance known as mime (no, not the silent, painted-face, stuck-in-an-invisible-box type of mime). Mime (*mimius*) was a semi-improvisatory performance with no masks and, though there were tragic mimes, the comic mimes were some of the most popular forms of entertainment in the Roman Republic (they often were the “warm-up” show and interlude for a Roman play). As a part of the Roman Floralia festival mimes were often performed naked. Furthermore, the related theatrical form of Roman pantomime, a non-spoken dance performance to music became more and more erotic in nature over the course of Roman history. Even as late as the 6thcentury CE, the Empress Theodora (married to Eastern Roman Emperor, Justinian I) rose to prominence as a pantomime actress that performed incredibly sexually erotic performances for the wealthiest people in Byzantium. Of course, the parallels and intersections of acting and sex work were both reality and perception. Regardless of whether a female performer did or did not engage in sex work, the perception of her as a sex worker was common and pervasive. As you identify, this perception remained well into the modern period.\n\nBut why, exactly, is acting so closely and easily associated with sex work? As Tracy Davis identifies in *Actresses as Working Women: Their Social Identity in Victorian Culture*, European theatre (not just in the Victorian age) “was ruled by distinct class and gender divisions.” For the sake of brevity, I’m going to be very broad for a moment as I expand on Davis’s assessment in the narrative of European history. The common social expectation for women was that their agency was only socially available within male contexts and contracts that left women few opportunities outside of domestic work and childbearing. Yes, there are great examples of women who were able to break and subvert these social constraints without engaging in sex work, but that was often the exception (again, a reminder, that this is a broad historical narrative and there are many exceptional cases in Euro-American history). Following the social and critical framework of Joseph Lenz in “Base Trade: Theater as Prostitution” in the journal *ELH*, a woman on stage might have been seen as independent and exercising her individual agency outside of the often strict social and gender constructs of their time. Thus, the audience (men and women) watching a woman on stage may have been more inclined to view the actor’s work, i.e. her agency, as parallel to sex work, an occupation populated by women surviving by means that were considered outside of social morays. This is a condition that continued well into the twentieth century and, to some degree, continues today.\n\nSo, to the point of your question: what changed? Well, to keep with the broad yet succinct historical narrative I’ve been working from, beginning in the early modern period women could find some degree of social mobility due to the perceived critical excellence of their work in theatre. Just like Theodora above, women who were considered excellent actresses could find some degree of respect in the exercise of their individual agency—in other words, they could make money, find independence, and take control of their own lives if their work met with critical success. BUT, just like Theodora never escaped the legacy of her early career, resulting in contemporaneous narratives and documentation that framed her as a sex worker or a former sex worker despite her raised station as Empress, even the most successful of female actors always had to fight against objectification, perceptions of sex work in their career, or other degrading insults regarding their sexual lives and bodies. Tracy Davis’s book that I cited above is a truly excellent historical examination of these cultural and social issues in the 18thand 19thcenturies. But women *could* rise from low-brow and amateur forms of theatre to the more respectable “high” art forms of theatre that developed throughout the modern period. For examples of the women that were able to rise socially and economically despite the enormous social constraints placed upon women from the 17thto the 19thcenturies see *The First Actresses: Nell Gwyn to Sarah Siddons*(2011). These women were incredibly talented and clearly skilled as actors, but their ability to succeed despite the common perception of female actors as sex workers was also a result of an emerging middle class experiencing a paradigm shift in how they perceived individual agency. This also meant that actors needed to rely less and less on the patronage of politically/aristocratically powerful individuals. As economies grew to include a middle class, relying more on manufacturing and trade than agrarian systems, there were more opportunities to find financial individuality (and thus some degree of agency), especially in urban environments.\n\nBut the big shift happened with the advent of mass media—namely film. Europeans and Americans could attend this more affordable form of performative storytelling in greater and greater numbers. The quick explosion of cinema coincided with the explosion of the middle class in the 20thcentury. And Americans especially saw themselves reflected in this new mass media form. American audiences saw themselves in those relatively unknown actors who could vault themselves to success through their hard work and talent. Again, I must stress that women still fought (and still fight) against perceptions of sex work as a means to their success. For more on how cinema targeted women’s sexuality in film see *Bad Women: The Regulation of Female Sexuality in Early American Cinema* by Janet Staiger. So, even though the work of female actresses isn’t as often seen to be parallel or intersecting with sex work, the objectification and masculine framing of female sexuality is still an issue that actors have to deal with today.\n\nI’ve tried to keep this succinct and, in that effort, have chosen some broad historical narratives to frame my answer. If you’d like more detailed or specific information please let me know!\n\nBibliography:\n\nRichard C. Beacham, *The Roman Theatre and its Audience*(Cambridge, MA: Harvard University Press, 1991).\n\nTracy C. Davis, *Actresses as Working Women: Their Social Identity in Victorian Culture*(New York: Routledge, 2002).\n\nEdith Hall, *The Theatrical Cast of Athens: Interactions between Ancient Greek Drama and Society*(Oxford: Oxford University Press, 2006).\n\nJoseph Lenz, “Base Trade: Theater as Prostitution,” in *ELH*60.4 (Winter 1993): 833-55.\n\nGillian Perry, Joseph Roach, Shearer West, *The First Actresses: Nell Gwyn to Sarah Siddons* (London: University of Michigan Press, 2011).\n\nJanet Staiger, *Bad Women: The Regulation of Female Sexuality in Early American Cinema* (Minneapolis: University of Minnesota Press, 1995)."
]
}
|
[] |
[] |
[
[]
] |
|
2hl76a
|
why it seems to be nearly impossible for plastic surgery to make someone look genuinely 20+ years younger.
|
Why do old celebrity women look like dolls every time they get surgery to try and look 30 years younger? The "young" features look too exaggerated to not be fake most of the time, is what I've noticed.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2hl76a/eli5_why_it_seems_to_be_nearly_impossible_for/
|
{
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"cktoynl",
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],
"score": [
4,
2
],
"text": [
"Real young is a lot more complicated and subtle than making a doll face. They can't exactly figure it out, but it's noticeable in the result. \n\nKinda like real/artificial vanilla extract. There's trace amounts of many chemicals in real vanilla extract that chemists can't really tell all of the chemicals, but in the result you can taste the difference. ",
"I have no expertise in this area.\n\nThat said, I feel that plastic surgery 'fixes' (tightens, sculpts, shaves) areas below the skin and the skin itself by pulling on it or cutting it away. While this may eliminate wrinkles and sagging, it doesn't correct the natural aging of the epidermis. IMHO, this is why people like Bruce Jenner (way too lazy to link) look scary.\n\nAgain, I'm a binge-watcher, not a doctor, damnnit! "
]
}
|
[] |
[] |
[
[],
[]
] |
|
k45cc
|
Is a "theory of everything" even possible?
|
I was listening to S. Hawkings' Brief History of Time and he mentioned how theories are broken down into general areas.. gravitation can't explain evolution, for instance.
So, assuming gravitation can be reconciled with quantum mechanics, yielded such a "Theory of Fundamental Forces", commonly called a "Theory of Everything", could this then be used to explain every other occurrence? Evolution, math, etc.
It seems to make no sense.. how can a unified theory of forces explain sexual selection, etc?
**EDIT**: Gödel's incompleteness theorems say that this is itself impossible.. a self-contained theory cannot explain itself. So if a set of axioms defining a Theory of Everything cannot be self-consistent.. why is it such a goal?
I can understand trying to unify gravity with quantum mechanics.. but thinking that the result can explain why the Earth's tilt is ~23 degrees and why pigs are colored as they are.. is just silly.
|
askscience
|
http://www.reddit.com/r/askscience/comments/k45cc/is_a_theory_of_everything_even_possible/
|
{
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"text": [
"This really gets down to philosophy, but the prevailing attitude among scientists - and one against which there isn't much evidence - is that all phenomena in nature come down to a theory or set of theories. So yes, something like sexual selection should certainly be described by things like electrodynamics and quantum mechanics, but there are so many steps along the way - from basic physics to atoms to molecules to cells and onward - that it becomes completely impractical to even consider solving problems in the higher up theory by recourse to the more fundamental one. It's the same throughout science; one isn't going to use quantum mechanics to solve problems in an organic chemistry class, and it would be quite advisable not to try, but it's perfectly clear that the laws of quantum mechanics which give rise to atoms and molecules are underlying all of organic chemistry. Similarly, we don't need to understand quantum electrodynamics in order to talk about Maxwellian electromagnetism, we don't need general relativity in order to talk about Newtonian gravity, we don't need quantum gravity to do standard particle physics calculations, even though in each case the former underlies the latter. These higher-up \"derived\" sciences tend to be largely independent of what they're made from - which we should be quite thankful for, because otherwise science would never get done!\n\nThat's one part of it, and the part that I think you were getting at. The other part is that some (but not most) physicists *do* suspect that physics can't be explained by one theory, but rather by a set of complementary theories which each describe their own separate domains of relevance. There are some reasons one might suspect this (most involve hand-wavy but decently credible appeals to the [incompleteness theorems](_URL_0_)), but I think one should hardly give up looking for a unified theory when the search has just barely begun! On cosmic timescales, at least.",
"First of all, math is its own thing. Math is *true*, and no physical theory is needed to \"explain\" it. Math is basically a language, and while the specifics were, at many points, suggested by the physical world, its proofs all lie squarely in the abstract world of pure logic, and it's therefore simply true. Math has no predictive power. If a particular bit of physics works according to some particular bit of math, that means that it works according to whatever is equivalent to that particular bit of math -- for example, we know the equation for a mass on a spring, and we can figure out the trajectory that the mass moves in from that equation. If the mass doesn't follow that trajectory, then the equation is incorrect. The equation is *equivalent* to the trajectory (well, to the family of trajectories). We might as well watch how the mass moves and figure out the equation from that, because they're the same thing.\n\nAs for the rest, the universe behaves according to a set of laws. We think. Well, we're pretty damn sure of it, anyway! Some people, namely people who believe in the various faiths, believe that there is some sort of magic at work. However, on a logical level, even that magic can be described using a set of meta-laws, if necessary. However deep you go, there exists *some* collection of laws. All of our \"theories\" are best guesses about that ultimate collection of laws. Quantum mechanics is a best guess about some aspects of that collection, and gravitation is a best guess about some other aspects of that collection, but those two guesses aren't entirely compatible, so a unified theory would be a guess at the entire collection of laws rather than just some aspects. Trouble is, we don't know what that would look like, since in our puny human understanding, we really can't see that well into the laws of the universe. Our eyes can only see so much, so we build microscopes. Actual light can only probe so deep, since it can't see anything smaller than its wavelength, so we build electron microscopes, but even they only go so deep. We have to build particle accelerators to look at finer and finer details, but we can't really *see* them; we have to infer them from theories like particle physics. Right now, particle accelerators are limited by the resources -- time, money, materials -- it takes to build them and get them running, but even that has a theoretical hard limit where we simply can't see any further. For example, we can't see what happens inside the event horizon of a black hole, period (unless we're already inside of it). But the hope is that eventually we will figure out all of the laws that govern the way the universe behaves, and this is theoretical physics.\n\nBut what about sexual selection, you ask? Well, an elementary particle by itself behaves in a fairly simple way. Two elementary particles behave in a much more complicated way. Three elementary particles, and even if they're just classical masses under the influence of gravity, we can't even solve for their trajectories! An organism is made up of MANY, MANY, MANY, MANY particles. On the order of 10^29 particles for a human (100 kg divided by the mass of a proton), just counting protons, neutrons, and electrons, and *not* counting photons, constituent quarks, and so on. Sexual selection deals with MANY persons, too, so it gets even more complicated! The basic laws of physics do explain sexual selection, but not in a way that we could possibly understand, since this phenomenon arises from the interactions of an absurdly large number of particles, each with its own trajectory. So we come up with aggregate theories with larger building blocks that *usually* work. We make up symbols, collections of particles -- for example, this collection of particles over here I call a desk, and this other collection of particles I call me -- since they behave roughly separately -- I will never be confused about what is my desktop and what is me, since the two never actually mix. I like my desktop, to some extent -- this means that my brain's neurons fire in a certain way when I think about my desk, partly from general principles it has developed -- it holds my computer, it's smooth enough that I can write on it, it's large enough that there's space for my girlfriend and I to both eat dinner while watching videos on my computer -- and partly from my history with this desk. All these thoughts are neuronal firing patterns, which are still governed by the laws of physics. Those firing patterns encode thoughts, and that encoding is still a mystery to us, one which we are solving. Someday, we might be able to explain sexual selection on the basis of neurons. However, even though *we* may not be able to explain it right now, it is *still* governed by the laws of physics. Will a unified theory of everything be able to explain sexual selection *better* than the various theories we have now? Probably not. The reason we have the theories we have right now is that they *work*, mostly. Mostly. There are some rough edges, but they work. Presumably, those rough edges are not really relevant to sexual selection, and if a grand unified theory is discovered, that won't affect the explanation of sexual selection except by adding a deeper level.\n\nAs a quick analogy, sexual selection is like a computer application. It was written in Python, which runs on an interpreter that was written in C (this isn't necessarily true, by the way), which was itself written in assembly, which has to be translated into machine code. The application is entirely written in machine code, and it follows the rules of machine code, but the human who wrote it did so in a much higher-level language without ever learning machine code or assembly language or maybe even C.\n\nAnyway, hope that makes sense!",
"This really gets down to philosophy, but the prevailing attitude among scientists - and one against which there isn't much evidence - is that all phenomena in nature come down to a theory or set of theories. So yes, something like sexual selection should certainly be described by things like electrodynamics and quantum mechanics, but there are so many steps along the way - from basic physics to atoms to molecules to cells and onward - that it becomes completely impractical to even consider solving problems in the higher up theory by recourse to the more fundamental one. It's the same throughout science; one isn't going to use quantum mechanics to solve problems in an organic chemistry class, and it would be quite advisable not to try, but it's perfectly clear that the laws of quantum mechanics which give rise to atoms and molecules are underlying all of organic chemistry. Similarly, we don't need to understand quantum electrodynamics in order to talk about Maxwellian electromagnetism, we don't need general relativity in order to talk about Newtonian gravity, we don't need quantum gravity to do standard particle physics calculations, even though in each case the former underlies the latter. These higher-up \"derived\" sciences tend to be largely independent of what they're made from - which we should be quite thankful for, because otherwise science would never get done!\n\nThat's one part of it, and the part that I think you were getting at. The other part is that some (but not most) physicists *do* suspect that physics can't be explained by one theory, but rather by a set of complementary theories which each describe their own separate domains of relevance. There are some reasons one might suspect this (most involve hand-wavy but decently credible appeals to the [incompleteness theorems](_URL_0_)), but I think one should hardly give up looking for a unified theory when the search has just barely begun! On cosmic timescales, at least.",
"First of all, math is its own thing. Math is *true*, and no physical theory is needed to \"explain\" it. Math is basically a language, and while the specifics were, at many points, suggested by the physical world, its proofs all lie squarely in the abstract world of pure logic, and it's therefore simply true. Math has no predictive power. If a particular bit of physics works according to some particular bit of math, that means that it works according to whatever is equivalent to that particular bit of math -- for example, we know the equation for a mass on a spring, and we can figure out the trajectory that the mass moves in from that equation. If the mass doesn't follow that trajectory, then the equation is incorrect. The equation is *equivalent* to the trajectory (well, to the family of trajectories). We might as well watch how the mass moves and figure out the equation from that, because they're the same thing.\n\nAs for the rest, the universe behaves according to a set of laws. We think. Well, we're pretty damn sure of it, anyway! Some people, namely people who believe in the various faiths, believe that there is some sort of magic at work. However, on a logical level, even that magic can be described using a set of meta-laws, if necessary. However deep you go, there exists *some* collection of laws. All of our \"theories\" are best guesses about that ultimate collection of laws. Quantum mechanics is a best guess about some aspects of that collection, and gravitation is a best guess about some other aspects of that collection, but those two guesses aren't entirely compatible, so a unified theory would be a guess at the entire collection of laws rather than just some aspects. Trouble is, we don't know what that would look like, since in our puny human understanding, we really can't see that well into the laws of the universe. Our eyes can only see so much, so we build microscopes. Actual light can only probe so deep, since it can't see anything smaller than its wavelength, so we build electron microscopes, but even they only go so deep. We have to build particle accelerators to look at finer and finer details, but we can't really *see* them; we have to infer them from theories like particle physics. Right now, particle accelerators are limited by the resources -- time, money, materials -- it takes to build them and get them running, but even that has a theoretical hard limit where we simply can't see any further. For example, we can't see what happens inside the event horizon of a black hole, period (unless we're already inside of it). But the hope is that eventually we will figure out all of the laws that govern the way the universe behaves, and this is theoretical physics.\n\nBut what about sexual selection, you ask? Well, an elementary particle by itself behaves in a fairly simple way. Two elementary particles behave in a much more complicated way. Three elementary particles, and even if they're just classical masses under the influence of gravity, we can't even solve for their trajectories! An organism is made up of MANY, MANY, MANY, MANY particles. On the order of 10^29 particles for a human (100 kg divided by the mass of a proton), just counting protons, neutrons, and electrons, and *not* counting photons, constituent quarks, and so on. Sexual selection deals with MANY persons, too, so it gets even more complicated! The basic laws of physics do explain sexual selection, but not in a way that we could possibly understand, since this phenomenon arises from the interactions of an absurdly large number of particles, each with its own trajectory. So we come up with aggregate theories with larger building blocks that *usually* work. We make up symbols, collections of particles -- for example, this collection of particles over here I call a desk, and this other collection of particles I call me -- since they behave roughly separately -- I will never be confused about what is my desktop and what is me, since the two never actually mix. I like my desktop, to some extent -- this means that my brain's neurons fire in a certain way when I think about my desk, partly from general principles it has developed -- it holds my computer, it's smooth enough that I can write on it, it's large enough that there's space for my girlfriend and I to both eat dinner while watching videos on my computer -- and partly from my history with this desk. All these thoughts are neuronal firing patterns, which are still governed by the laws of physics. Those firing patterns encode thoughts, and that encoding is still a mystery to us, one which we are solving. Someday, we might be able to explain sexual selection on the basis of neurons. However, even though *we* may not be able to explain it right now, it is *still* governed by the laws of physics. Will a unified theory of everything be able to explain sexual selection *better* than the various theories we have now? Probably not. The reason we have the theories we have right now is that they *work*, mostly. Mostly. There are some rough edges, but they work. Presumably, those rough edges are not really relevant to sexual selection, and if a grand unified theory is discovered, that won't affect the explanation of sexual selection except by adding a deeper level.\n\nAs a quick analogy, sexual selection is like a computer application. It was written in Python, which runs on an interpreter that was written in C (this isn't necessarily true, by the way), which was itself written in assembly, which has to be translated into machine code. The application is entirely written in machine code, and it follows the rules of machine code, but the human who wrote it did so in a much higher-level language without ever learning machine code or assembly language or maybe even C.\n\nAnyway, hope that makes sense!"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/G%C3%B6del%27s_incompleteness_theorems"
],
[],
[
"http://en.wikipedia.org/wiki/G%C3%B6del%27s_incompleteness_theorems"
],
[]
] |
|
6ec0ci
|
Why does a solution of antifreeze and water raise the boiling point?
|
We did a practical research task of the boiling point of antifreeze solutions of varying concentrations, and higher concentrations had higher boiling points. Is there a reason on the chemical scale for why this happens?
|
askscience
|
https://www.reddit.com/r/askscience/comments/6ec0ci/why_does_a_solution_of_antifreeze_and_water_raise/
|
{
"a_id": [
"di99688"
],
"score": [
3
],
"text": [
"The concept is called \"boiling point elevation\". Any substance dissolved in any other substance will raise the boiling point. It doesn't matter what the solvent is or what the solute is, only the amount matters (as long as the solute's boiling point is way above the solvent's). This is basically because the solute has to be taken into account when determining the boiling point, and since the solute isn't close to boiling at the temperature water boils at the net effect is to reduce the boiling point.\n\nTo put it in more chemical terms, the boiling point of water is the temperature at which the water molecules have so much energy that they are exactly as likely to leave the liquid and escape into the air as they are to leave the air and enter the liquid. \n\nWhen you add the solute, you now have a case where the liquid includes both water molecules and solute atoms or molecules, while the air has water molecules but little or no solute. This means that a given atom/molecule of solution is less likely to escape into the air at a given temperature because you have to average across both the water molecules and the solute atoms/molecules, while the water molecules in the air have the same probability of going back into the liquid. This shifts the boiling point upwards."
]
}
|
[] |
[] |
[
[]
] |
|
mzili
|
Why doesn't HSV-1 transfer to other parts of your lip? Does genital herpes function the same way?
|
askscience
|
http://www.reddit.com/r/askscience/comments/mzili/why_doesnt_hsv1_transfer_to_other_parts_of_your/
|
{
"a_id": [
"c354ocy",
"c354ocy"
],
"score": [
9,
9
],
"text": [
"Herpes resides in your nervous system, not your lips. The infection you see as a cold sore is an inflammation response to a newly reactivated bit of virus at the tip of a nerve under the skin that colonizes some minor damaged tissue on the lips.\n\nThe reason it is reactivated is not clear: herpes is usually dormant for awhile after infection then spontaneously pops up due to signals we don't entirely understand. It can cause sore on just about any place with lots of nerves or weak tissue, so it can get in the eyes or on the fingers. \n\nBut as for the reason it doesn't spontaneously shift it is likely the same reason you don't immediately get cold sores after your first infection: newly infectious virus particles don't cause immediate symptoms, and you already have antibodies and a latent infection.\n\nThis is borne out by the fact that immunocompromised people do get long spreading lesions called \"knife cut\" lesions and potentially life-threatening outbreaks.",
"Herpes resides in your nervous system, not your lips. The infection you see as a cold sore is an inflammation response to a newly reactivated bit of virus at the tip of a nerve under the skin that colonizes some minor damaged tissue on the lips.\n\nThe reason it is reactivated is not clear: herpes is usually dormant for awhile after infection then spontaneously pops up due to signals we don't entirely understand. It can cause sore on just about any place with lots of nerves or weak tissue, so it can get in the eyes or on the fingers. \n\nBut as for the reason it doesn't spontaneously shift it is likely the same reason you don't immediately get cold sores after your first infection: newly infectious virus particles don't cause immediate symptoms, and you already have antibodies and a latent infection.\n\nThis is borne out by the fact that immunocompromised people do get long spreading lesions called \"knife cut\" lesions and potentially life-threatening outbreaks."
]
}
|
[] |
[] |
[
[],
[]
] |
||
1lwr9n
|
what is going on with my body while i stand near a working microwave and why do i feel weird?
|
Microwaving some leftovers (fetuccine neopolitan if you must ask) and noticed this.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1lwr9n/eli5_what_is_going_on_with_my_body_while_i_stand/
|
{
"a_id": [
"cc3i90v",
"cc3ihk4",
"cc3ii44"
],
"score": [
2,
3,
10
],
"text": [
"Maybe you are sexually attracted to your microwave? I feel the same way around lamp posts. Ooh I'm getting hot just thinking about it!",
"Haven't experienced anything like that. \nMicrowaves don't really do significant damage to your body, nor should you 'feel' it.",
"Nothing is happening to your body near a microwave that isn't happening anywhere else, assuming you are using a normal microwave that isn't falling to pieces. At most, a microwave oven leaks about 5 milliwatts of radiation measured 5cm from the oven. In contrast a cell phone emits about 1.6 watts. You do the math."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
7ny3m8
|
how tv comapnies broadcast channels via cables & antenna?
|
So I know they can either broadcast the channels via Antenna, Cables or Internet..
What I wonder is what is the process and devices the TV companies use to receive and send the channels to the end user, so their controller at one's home can broadcast it to the tv?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7ny3m8/eli5_how_tv_comapnies_broadcast_channels_via/
|
{
"a_id": [
"ds5hamb"
],
"score": [
3
],
"text": [
"TV is broadcast over the air using a very large antenna and high power amplifiers. Amplifying the signal and hooking it up to a metal antenna causes the antenna to resonate, and that sends out an electromagnetic wave. At your end, a resonance is caused in your antenna by that EM wave, and it is then amplified and sent to your tuner to separate out the signals to send on to the display and audio. (Radio works the same way, but there's no video signal.) \n \nCable companies multiplex (combine) many signals onto a high-frequency carrier signal, and that signal goes out to all of their cables (and fiber optics). It goes through miles of cables and repeaters until it gets to your house. There it is amplified and your cable box de-multiplexes (splits out) the channel you want to watch, ignoring the carrier and all of the other channels. Then like broadcast TV, the video and audio signals must be separated out by a tuner (either in your cable box or in your TV). \n \nOver the internet, the video and audio signals must be digitized into a specific format and put into packets (large groups of bits) that say where they are going, where they are from, what packet number it is, etc. That stream of packets is sent out and routed through many routers, signal repeaters, etc. until they finally get to your home computer or TV. The packets then need to be re-assembled into a stream of bits that contains both the video and audio data. Those are separated out and sent to different circuits. "
]
}
|
[] |
[] |
[
[]
] |
|
3wmbo2
|
why do "forever storms" seem to exist in some planets like jupiter (and now stars)? how do they stay "forever" and not die?
|
Link to the [discovery of a star with a "forever storm"](_URL_0_)
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3wmbo2/eli5_why_do_forever_storms_seem_to_exist_in_some/
|
{
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"cxxam6o",
"cxxfrbj"
],
"score": [
13,
3
],
"text": [
"They're not forever. Jupiter's storm is losing it's energy and will die out eventually. I think it's been overdue for almost a decade, but I'll let someone else find the literature on it.",
"Forever storms survive by eating smaller storms. There was a good video a few months ago, can't find it now though."
]
}
|
[] |
[
"http://gizmodo.com/this-stormy-star-is-unlike-anything-weve-seen-before-1747704300"
] |
[
[],
[]
] |
|
c0b5ho
|
Is there an underlying meaning to why Hitler and the people stuck an arm out at each other when doing the “Heil” salute?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/c0b5ho/is_there_an_underlying_meaning_to_why_hitler_and/
|
{
"a_id": [
"er3d0vw"
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"text": [
"I've written about the salute before so will rework some of that here.\n\nThe Nazis did not invent it themselves. The 'Nazi Salute' was chosen because it was the 'Fascist Salute' already popularized by the Italian Fascist Party under Mussolini. Other Fascist aligned movements, such as the Spanish Falangists also adopted the gesture in similar imitation of the 'Ur-Fascist' group.\n\nWe'll return to the Nazis later, but now the first question to tackle is why did the Italians decide on the gesture? Mussolini was obsessed with creating a new Roman empire, and he adopted trappings of 'Rome' as the symbols for the party in furtherance of that. The name itself, \"Fascist\", comes from the *fasces* which had once been a symbol of power and authority in Ancient Rome. The salute that they made use of, with the arm extended outwards, fingers together, palm down, was known as the \"Roman Salute\", so of course was only appropriate that it would be the salute of the 'New Rome'. The association of the salute and a revitalized Roma-Italian Nationalist ideology predated Mussolini, who was likely influenced in picking it by the proto-Fascist thinker Gabriele D'Annunzio, who had implemented the salute during his shortlived control of the city of Fiume, and is the one who introduced it into that nationalist Italian lexicon.\n\nBut this still leaves us with another question to follow. Was the \"Roman Salute\" *actually* Roman? To which the answer is a fairly certain no! In no extant Roman sources or surviving Roman works of art is there representation of the salute that bears the name of Rome. We have evidence of salutes that involved raised hand but not in that manner - the closest examples, seen on Trajan's Column, have the fingers splayed out - and salutes not dissimilar to the modern military one as well. The famous statue *[Augustus of Prima Porta](_URL_2_)* although assumed by some to possibly be a Roman salute, almost certainly isn't. Aside from finger position, the simple fact is that the arm is a later restoration not original to the torso, and once upon a time the raised arm held a spear. Likewise, the *[Equestrian Statue of Marcus Aurelius](_URL_1_)* on the Campidoglio can be erroneously identified as a Roman Salute, and was so even by the Fascists themselves, but it only works from very specific angles - close in, staring up - and is generally agreed by art historians to be a gesture of \"benediction\", one which is is much more easily identified as from many angles.\n\nBut if it isn't authentically Roman, than what is it? In this regard, if there is any one, single culprit, it is certainly *[Oath of the Horatii](_URL_4_)*, a late 18th-cen. neoclassical work showing a scene from Roman history of the Horatii, three brothers who triumphed in combat over the Curiatii, as they give their oath their father prior to the combat. It is an evocative piece, considered a true masterpiece of the style of hugely influential as a work of art:\n\n > The impact of the Oath was so revolutionary in the aesthetic realm that it radically altered the way artists made art and the way critics perceived it. [...] Modern historians have often referred to this as a pivotal work, one that signaled a decisive departure from the predominant, classicized Rococo style.\n\nBut its influence is beyond simple art, and for our purposes, it is the straight armed, fingers together, palm down salute that they render to their father accompanying the oath, although this of course ties into its aesthetics. \n\nUnlike the actual *Roman* works where any similarities to the \"Roman\" Salute fall apart on examination, *this* one is unmistakable. It still isn't perfect, as they are at differing angles, and a mix of right and left arms, but the parallels, and the *context*, are unmistakable. Of course, the scene itself is a creation, a fanciful representation of filial and civic devotion that is not present in Roman accounts of the (mostly mythical) story, but that is quite secondary. Just as the scene is a creation, as too is the anachronistic clothing and weapons, the salute represented in the painting was chosen because of how it would impress the scene into the mind of the viewer, something which it is unarguably effective at. Although possibly influenced by Roman images that showed Roman oath scenes where, weapon in hand, the soldiers pointed their swords downward, and the Roman oath motif generally was hardly alien to European art of the period , such as the *[Oath of Brutus](_URL_3_)* by Gavin Hamilton that predated David's work by 20 years, but as Rosenblum put it, the style and gesture, including this new, specific conception that was David's conception of the salute, left earlier works of \"classical virtue [...] flaccid in both style and moral conviction\".* Although the caveat must of course be that this is art, so it is necessarily subjective. Carrier certainly would disagree with such strong words, in his direct comparison of the two works noting the comparative \"greatness\" is not easy to answer, even is he agrees \"the claim that Hamilton made a greatest painting than David is unconvincing\".\n\nThe specific degrees of greatest though are not really our concern, insofar as the general tenor of critical acclaim, and especially how it relates to the use of gestures in the work. Much of the power of the painting is ties up the 'language of gesture' present in the work. It was, in fact, specifically the fact that David had chosen an essentially *new* gesture that helped get that across, since as Johnson notes of the debut:\n\n > The counterpoint of the right hand of the father is the group of swords clenched i n his left (an enormous feat of physical prowess), to which his sons swear allegiance with their pronated hands and by which two will perish . Most critics of the time were fascinated by the powerful impact of this pantomimic invention, which diverged so dramatically from well-known contemporary representations of antique, oath-taking scenes.\n\nOne such critic is quoted by her thus:\n\n > I will agree that it is a great conception and that it is executed as boldly as it is skillfully and I am as entranced as you are with the action of the Horatii, who embrace each other during their Oath, a sublime and symbolic expression of their union, of the sacred and courageous friendship that unites them, and of the common object that brings them closer and links them to one another until death, these three warrior brothers.\n\nLater works would likely be influenced by David's powerful use of body language and gestures, such as Jean-Léon Gérôme's *[The Death of Caesar](_URL_5_)*, where the arms of the tyrannicides, thrown upwards weapons clasped, possibly draws from *The Oath*, \"express[ing] a kind of reaffirmation of their allegiance, a renewal, as it were, of their sworn brotherhood.\" Certainly David himself knew that he had struck something good, as the same gesture shows up in his later *[The Tennis Court Oath](_URL_6_)*, a work depicting the titular event in the French Revolution, and almost certainly did so not only because of the power of the gesture itself, but to consciously connect his two works, and the connection between both the ancient and modern oath. By 1810, and his work *[The Distribution of the Eagle Standards](_URL_0_)*, *hopefully* you're noticing the theme here, namely that he knew to milk this thing for all its worth, but more importantly it should be noted that the meaning is expanding, and the oath is more imperial, Napoleon's military commanders showing him their loyalty. And although obviously a *French* scene, the gesture, through its genesis, was now a *Roman* one - Napoleon too going back to that old Empire for symbolism - and it is impossible to not envision the composition of the work unchanged, and only the figures transposed, with Italian Black Shirts, or Nazi SS men taking the place of the French soldiery. For this scene, which shows an event three days after the Emperor's coronation when the regimental commanders came to swear their oath of loyalty to him, as Boime poignantly notes the shift:\n\n > The series of oath pictures may be seen as the coding of key developments in the history of the Revolution and its culmination in Napoleonic authoritarianism. [...] The civil pride of French nationalism won during the Revolution had been displaced onto pride in battlefield glory, and the welfare of the French citizenry taken as a whole became subordinated to the prestige of the troops. Symbolically this was further represented by shifting the ancient paradigm from the republic to the empire."
]
}
|
[] |
[] |
[
[
"https://upload.wikimedia.org/wikipedia/commons/b/b0/Jacques_Louis_David-Serment_de_l%27arm%C3%A9e_fait_%C3%A0_l%27Empereur_apr%C3%A8s_la_distribution_des_aigles%2C_5_d%C3%A9cembre_1804.jpg",
"https://upload.wikimedia.org/wikipedia/commons/5/59/Marco_Aurelio_bronzo.JPG",
"https://upload.wikimedia.org/wikipedia/commons/e/eb/Statue-Augustus.jpg",
"https://upload.wikimedia.org/wikipedia/commons/c/c5/Gavin_Hamilton_-_the_oath_of_brutus.jpg",
"https://upload.wikimedia.org/wikipedia/commons/3/35/Jacques-Louis_David%2C_Le_Serment_des_Horaces.jpg",
"https://upload.wikimedia.org/wikipedia/commons/1/12/Jean-L%C3%A9on_G%C3%A9r%C3%B4me_-_The_Death_of_Caesar_-_Walters_37884.jpg",
"https://upload.wikimedia.org/wikipedia/commons/6/6d/Le_Serment_du_Jeu_de_paume.jpg"
]
] |
||
ra0d6
|
Would travelers using an Alcubierre drive experience time dilation?
|
In the scenario of which I am thinking, let's say I travel towards a recognizable constellation 1,000 light years away (assume all stars in the constellation are same distance from Earth). We on Earth are obviously seeing that constellation as it was 1,000 years ago.
So, a couple of questions...
1. Would Earth see me zoom away at faster-than-light speed?
2. Let's say I fly for an hour (my time, if it's any different than Earth time) and get 90% of the way there; during my trip do I see the last 900 years of that constellation's star-drift in "fast-forward" mode?
3. Or would I just see a blinding white light the whole trip? Then as I decelerate to a stop, I see the constellation at 100 years old?
If anyone needs me to elaborate, please ask.
|
askscience
|
http://www.reddit.com/r/askscience/comments/ra0d6/would_travelers_using_an_alcubierre_drive/
|
{
"a_id": [
"c445y3p"
],
"score": [
4
],
"text": [
"This may help others- \n\n_URL_0_\n\nHelped me!\n"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Alcubierre_drive"
]
] |
|
3itbdi
|
Why, besides a few exceptions, is all of the most popular classical music from Central and Eastern Europe?
|
You never hear about Portuguese or Norwegian composers. I feel like English and French composers of "classical" music aren't really spoken about much either. Seems like everything that is still played today is German, Austrian, Italian, Russian, Czech, etc.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3itbdi/why_besides_a_few_exceptions_is_all_of_the_most/
|
{
"a_id": [
"cujjwza",
"cujl7br"
],
"score": [
7,
5
],
"text": [
"German, Austrian and Italian composers dominated the baroque and classical eras of Western music, which is what is commonly thought of when we think of \"classical music\" today. However, in the early modernist era of the late 19th and early 20th century, the influence of composers from other areas of Europe cannot be ignored. For example, French composers like Claude Debussy and Maurice Ravel were crucial to the impressionist movement around this time, and Englishman Edward Elgar wrote many works which are considered standards today, such as The Enigma Variations and the Pomp and Circumstance Marches. Meanwhile, Charles Ives of New England received critical attention for his merging of classical music with American folk sounds, while the Hungarian Bela Bartok's study and elevation of traditional Hungarian and Eastern European folk helped influence modern Ethnomusicology. These are just a few examples out of many composers of the period from all over Europe and North America.",
"My answer is going to focus heavily on the 18th Century for the first part, in which Austro-German and Italian composers are by far the most widely played. After this I'll discuss the 19th century into which some Russian composers and other Eastern European composers come into play. \n\nThe use of \"popular\" in your question really defines your answer. Music suffers heavily from a teleological approach to historical studies, resulting in what has been referred to as the mainstream musical canon (or imaginary museum, to use Nicholas Cook's term from \"Music: A Very Brief Introduction\" which gives a great insight into many areas of musical study). \n\nThis approach to studying music did not come about purely by accident but was a result of a number of factors, both musical and socio-political. Music in the Austro-German tradition tended to concentrate heavily on certain aspects of music, including but not limited to form, harmonic progression and, in a more abstract sense, appealed to the values of the imperialistic societies of its time. Charles Rosen makes a good job of analysing music of the 18th and 19th century in this style in his renowned book \"The Classical Style\". However, in a way, books like \"The Classical Style\" only serve to further the canon even more into the 21st century, but I'll talk a little about that in a minute.\n\nHowever, even though German music was more highly valued than the \"popularist\", melodic, Italian music (perhaps because, being mostly instrumental rather than operatic, it was seen as timeless, rather than an aging reflection of the times) you're quite right in saying that both traditions from the 18th century enjoy far greater popularity today than music from other places. This comes down to a couple of things; both countries were the among the first to widely accept the tonal system made popular around 1730-1750. Retrospectively, this caused historians and musicians alike to gravitate towards using them as musical examples, and ignore composers who used musical methods that ended up in a historical dead-end, so to speak. It also cannot be underestimated how much of a cultural centre Vienna was during this time, and to a lesser extent Italy too. Vienna, in particular, had the double-whammy of being known as a centre of Enlightenment and haven for the arts while at the same time being under the strict rule of the Empire, resulting in free art that was not upset by ideas of Revolution in the same way France was. There's some great contextual details about Vienna, and the wider late-18th century, in Tim Carter's informative guide to the Marriage of Figaro. To name some composers that lived and studied in Vienna: Haydn, Mozart, Beethoven, Schubert. The world was, in a sense, looking to Vienna to produce art rather than looking to themselves, and Vienna gave these composers as payment. Much of the 18th century canon comes down to nations and cities in Europe not **wanting** independence, but instead wanting to be as fashionable, popular and cultured as places like Vienna, resulting in the glorification of foreign composers over their own.\n\nMuch of this changed in the 19th century, though not necessarily for good reasons. Nationalism became extremely important, and remained so until the Second World War, a century and a half later. Nationalism cuts both ways in music. It produced scholars and musicians who regarded themselves as the \"next step\" in musical history, based on what they knew had come before. Now, the problem is, much of the only accepted music across Europe was Austro-German (as discussed above). This left other countries defining themselves **against** this culture, the mainstream, while composers from this culture were free to define themselves as \"the norm\", the good, the superior. There are many, many books on musical nationalism and I won't pretend I know them all - but I do know a good book analysing it and studying it impartially is Edward Said's \"Orientalism\". The situation of the musical canon now sits firmly in the hands of the Austro-German. Europe looks to them for inspiration - either producing composers that write in their style or composers who aggressively do **not** write in their style. However, the only composers that are well-known today are those who wrote in a German style with inflections of their own \"folk\" traditions - such as Tchaikovsky, Dvorak and, later, Sibelius. For an Austro-German audience, they saw something exciting and exotic that did not threaten their cultural dominance. Today, musical repertoire is comprised still mainly of what the Austro-German canon was at the end of the 19th century - German-speaking composers (Wagner, Liszt, Beethoven, Mozart, Bach, Haydn, Schubert, Schumann, Brahms, Strauss etc) and German-style exotic composers (Berlioz, Chopin, Mussorgsky etc). \n\nModern musical texts, generally, do not help the situation even while accepting that the society-created canon of \"good\" works still exists. For example, Richard Taruskin's monumental \"Oxford History of Western Music\" does a very good job of describing the canon, its faults and causes - before going on to describe the history of those composers contained in it **anyway** instead of concentrating on bringing all elements of \"Western\" music to study, not just the famous ones. \n\nHowever, it's not that there is a lack of sources for contemporary music to \"the greats\" that can be studied and played. I have personally worked with a publishing company called INTRADA that specialise in finding music written at the same time as composers mentioned above, particularly in the 18th century, but written in a different musical style. These pieces are then published and recorded - but, they never make it too far into mainstream repertoire, perhaps because modern audiences are content with the security they have in their model of history and wouldn't benefit from shaking it up.\n\nI hope I have answered your question. The popularity of the mainstream canon, which we still listen to today, comes from a variety of reasons centring around the cultural hub of Vienna, and national reactions to German music in the 19th century. I'm going to write, for a paragraph or so, about the 20th century below because it provides a really interesting counterpoint to the canon.\n\nDuring the 20th century, nationalism became its most powerful, producing composers like Schoenberg who believed he had perfected the Austro-German tradition, and analysts like Schenker who tried to prove German superiority through complex analytical methods. This, of course, tied very neatly in with the fascist government that arose before WWII. To a lesser extent, the same happened in Italy under Mussolini, though composers there were undergoing a little more of an identity crisis, their powerful musical culture having been supplanted by Austria-Germany in the preceding century. This information I have learnt from Richard Causton, an expert in Italian music of the 20th century. After the war, German and Italian composers felt that they needed a break, a \"day zero\" to quote Stockhausen - where they completely abandoned the technique used by their aggressively-nationalistic predecessors. As a result, the new style of electronic music came into being while other countries remained composing with largely traditional means. I am over-generalising slightly but the core point is true. I find it interesting that German composers shied away from their culturally dominating past, only to create a new style of music that was in its own right extremely influential in the 20th century. But the 20th century is not what your question was about, just a little side-note. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
1c1zom
|
Is it possible that some pathogens or viruses have evolved to cause coughing/sneezing symptoms in its victims to encourage it to spread?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1c1zom/is_it_possible_that_some_pathogens_or_viruses/
|
{
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"c9cf1dv"
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"score": [
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"text": [
"I'd say the other way around, to be pedantic. Some pathogens evolved traits that lead to coughing/sneezing and could travel well in air/mucous, thus were spread extensively, and thus the trait perpetuates.\n\nThey didn't develop the trait *to* do a thing, but the trait mutated randomly and *did* lead to success, thus it persists."
]
}
|
[] |
[] |
[
[]
] |
||
9qwnwa
|
If there is little to no friction or gravity in outer space to slow an object down, how come a space shuttle has a maximum speed? (Apparently around 28,000 kilometers per hour). Why can’t a spaceship continue to build momentum to reach up to light-speed?
|
askscience
|
https://www.reddit.com/r/askscience/comments/9qwnwa/if_there_is_little_to_no_friction_or_gravity_in/
|
{
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4
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"text": [
"They run out of fuel.\n\nYou can bring more fuel, but that increases the mass of the shuttle, which means that you get lower acceleration until you've burned that fuel up. If you ignore gravity and the atmosphere and just think about a single rocket with fuel, then it follows the \"Tsiolkovsky rocket equation\", which is\n\nchange of velocity = (speed of stuff ejected out of engine) x ln (1+(mass of fuel/mass of rest of rocket) )\n\nwhere ln is the natural log.\n\nWhat this means is that you get diminishing returns as you increase the fuel mass, because the natural log function only increases very slowly. If you increase the fuel mass from 1x of the \"dry mass\" of the rocket up to 100x (i.e the rocket mass is over 99% fuel), then you've only made the rocket about 6-7 times faster.\n\nAt some point, it becomes far too expensive to add more fuel to just add a bit more speed, so we end up trying for a good compromise between making a rocket go fast, and having a rocket affordable enough that you can do other missions.\n\nOf course, you can partially get around this with multi-stage rockets, where you decrease the rocket mass as you go. But you can't do this forever, because you need to have an engine powerful enough to eject gas at a high speed without breaking, and you also need to have some mass for your cargo and passengers and equipment.\n\nYou can also try to refuel the rocket, but this also has diminishing returns. This fuel is now cargo for another rocket, and this new rocket has to carry this fuel up to a speed that matches the first rocket so it can catch up and hand over the fuel. So you end up spending a huge amount on fuel anyway.\n\nSo yeah, it's not a situation where a space shuttle can't go beyond a certain speed because it'll break or something. It's just the limit of how efficiently you can accelerate it until you run out of fuel.",
"In addition to the (very good) response by /u/Astrokiwi, there are all sorts of small particles scattered throughout space. At low speeds, this isn’t too much of a problem. But at high speeds, it becomes an issue.\n\nAt just 1% of the speed of light, something with the mass of a baseball has kinetic energy approximately equivalent to [exploding 150 tons of TNT.](_URL_0_) While not all of that will necessarily be transferred on impact, you still end up with a sizable hole in you spaceship.\n\nLess of a physical limitation than a practical one, but it does tie in the the idea of friction."
]
}
|
[] |
[] |
[
[],
[
"http://www.wolframalpha.com/input/?i=0.5%280.142kg%29%2A%280.01c%29%5E2"
]
] |
||
1uvinf
|
Because wind is just the movement differences in air temperature and pressure, will it ever reach an equilibrium?
|
Over time, shouldn't defusing equalise the temperature and pressure so that there is no more wind?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1uvinf/because_wind_is_just_the_movement_differences_in/
|
{
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"text": [
"no, there is many things, why not:\n\n1. we have day/night cycle - in part of world is night, so it's colder, in part is day, so it's warmer\n\n2. earth is inclined, so there is big difference in temperature between north and south.\n\n3. \"world\" is uneven, we have water, deserts, ice, etc. every \"reacts\" to sun in different way. water is \"accumulating\" heat, ice is \"bouncing\" sunlight and so on.",
"Nope. There are too many hydrodynamically unstable things in the system. For example, just having spinning motion in a curved reference frame can cause [unexpected instability](_URL_0_). Also, natural convection is known to cause [instability in the form of convection rolls](_URL_1_). A very simplified model of this theory is known to go [chaotic](_URL_2_) for when the temperature difference becomes large enough. These are all simple, idealized systems and they all go unstable and unpredictable fairly easily.\n\nNow take the earth... it's a rotating sphere. It has all sorts of natural convection (ground warms, upper atmosphere cools). There's day/night forcing. There's seasonal forcing. Theres oceans which develop their own currents due to instability. There are mountains. There are changes in density due to humid/arid regions. You get the idea. There is no reason to think that this real system is predictable, let alone that it has a stable solution it will equilibriate to... especially when so much of it is composed of unstable systems."
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Taylor%E2%80%93Couette_flow",
"http://en.wikipedia.org/wiki/Rayleigh-B%C3%A9nard_convection",
"http://en.wikipedia.org/wiki/Lorenz_system"
]
] |
|
2ws390
|
The sun is white even though when observed through the atmosphere it appears yellow/orange. Are all stars white when viewed outside the atmosphere or are some different colours?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2ws390/the_sun_is_white_even_though_when_observed/
|
{
"a_id": [
"cotnari"
],
"score": [
16
],
"text": [
"No, stars have colors from red to white to blue.\n\nStars approximately emit their light as [blackbodies](_URL_0_) of certain temperatures. The coolest stars are around 3000K, the hottest upwards of 40,000K.\n\nHow that temperature maps to color in your eyes is very complicated, but stars will basically fall along the [Planckian locus](_URL_1_) ([image](_URL_2_)). The Sun happens to be around 6000K, which falls near the white section, but cooler stars will be oranger/redder and hotter stars will be bluer."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Black-body_radiation",
"http://en.wikipedia.org/wiki/Planckian_locus",
"http://upload.wikimedia.org/wikipedia/commons/b/ba/PlanckianLocus.png"
]
] |
||
3aohhs
|
why bill gates and paul allen have such different wealths even though they both founded microsoft?
|
I'm sure they had other business ventures etc but can't find anything simple online to sum it up.
Thanks.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3aohhs/eli5_why_bill_gates_and_paul_allen_have_such/
|
{
"a_id": [
"csei2u4"
],
"score": [
3
],
"text": [
"The orginal founding percentages of MS were 64% for gates and 36% for Allen. Balmer got a $50,000 salary plus a 10% profit share. The profit share to Balmer was getting to be to much as MS started to grow, so they restructured.\n\nIn exchange for cancling his profit sharing agreement, Balmer got 8% of the company. Another 8% was split among other employees. The remaining 84% was split between Gates and Allan. Assuming they kept the same ownership split they began with Allen now owns 34% of 84%. So he now owns about 24.5% of the total company.\n\nFrom there it gets more murky. As MS took on other investors, they would have had to give up portions of the company. Some of that would come from each of the founders. \n\nBut since the IPO, both Gates and Allen have been able to sell shares on the open market. As many as they want. So from the time of the IPO (1994, I think), the net worth of the individuals would depend on when they sold the MS stock. "
]
}
|
[] |
[] |
[
[]
] |
|
1mubvv
|
why are the united states, liberia and burma the only three countries in the world not to implement the metric system as their standards weights and measures?
|
I read somewhere a few weeks back that it costs countries, who import from the US, millions upon millions of dollars each year to re-lable/convert the weights and measures of products into the Metric System for local distribution. It would make sense for the gradual transition to the Metric System to happen.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1mubvv/eli5_why_are_the_united_states_liberia_and_burma/
|
{
"a_id": [
"cccotsl",
"cccphq5",
"cccts33",
"cccu2ck",
"cccuim5",
"cccz0x2",
"ccczsm1"
],
"score": [
14,
9,
2,
2,
3,
2,
2
],
"text": [
"Inertia, tradition, and the expense of converting everything in one of largest and most populous nations on Earth to a new system. ",
" > it costs countries, who import from the US, millions upon millions of dollars each year to re-lable/convert the weights and measures of products into the Metric System for local distribution.\n\nAnother country having problems labeling products is not an incentive to change the thinking of 300,000,000 people.\n\nThe scientific community already does its measurements in metric. There's no incentive for Jane Smith to change the way she's thought of weights, distance, and temperature for 40 years. It works for us, so there's no driving force for a change.\n\n",
"Gerald Ford tried to implement it, Ronald Reagan shut it down to save money.\n\n_URL_0_",
"The cost of staying the same has to be greater than the cost of changing. Currently the cost of change is greater.",
"As far as origin goes: Liberia was founded by American slaves who re-colonized Africa and they used the US as their political and cultural model. English is their official language, the architecture's inspired by the antebellum South, their flag is an homage to the US's, etc. \n\nOn conversion: Too many logistics that come with it for them to bother at this point. Burma may since they're odd man out, but the US has enough influence to ignore Metric and force everyone else to deal.",
"What if i told you the metric system is used in the us...",
"Whenever I think about how great it would be if the USA converted 100% to metric, I immediately remember the construction trades and the fucking nightmares that would arise when everybody needs two sets of tools for the next hundred+ years and people have to hang signs on their houses that tell you they're either a metric house or a standard house. Take simple framing as an example. 16 inches on center. What's the metric equivalent? (No really , what is it?) And if you're improving existing construction, how do you know what's behind the drywall? I tell ya I lose sleep over it. "
]
}
|
[] |
[] |
[
[],
[],
[
"http://en.wikipedia.org/wiki/Metrication_in_the_United_States#20th_century"
],
[],
[],
[],
[]
] |
|
3i0je3
|
what are the difference between browser add-ons, like what firefox uses, and extensions, such as what chrome uses?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3i0je3/eli5_what_are_the_difference_between_browser/
|
{
"a_id": [
"cuc88fp",
"cuc8iyt"
],
"score": [
2,
2
],
"text": [
"Nothing - there's some minor differences in how each browser handles extensions, what they're allowed to do etc. but this isn't indicated by the different wording - they just picked different names. Could have used 'plugin' for example.",
"Here add-ons and extensions mean the same thing. The point of the news are that Firefox will change the way their add-ons currently work to a way more similar to the way the Chrome extensions work. Firefox wants to move to a multi-process environment, giving each tab a new process (like you can see in your task manager). This means that they need to change the way their add-ons work as well.\n\nYou can read more here: _URL_0_"
]
}
|
[] |
[] |
[
[],
[
"http://arstechnica.com/information-technology/2015/08/mozilla-sets-plan-to-dump-firefox-add-ons-move-to-chrome-like-extensions/"
]
] |
||
ad7hms
|
Is a figure 8 solar system possible?
|
I was wondering if it is possible for a solar system to exist where there are two suns that are essentially identical and a decent distance from each other so that the planet(s) are able to pass between them at one point in their orbit. Creating a system where the planet(s) are revolving around one star, get caught in the middle, and then latch onto the other star and start revolving around that one, starting the cycle over again.
|
askscience
|
https://www.reddit.com/r/askscience/comments/ad7hms/is_a_figure_8_solar_system_possible/
|
{
"a_id": [
"edejdwg",
"edeuevk",
"edf2lf7"
],
"score": [
8,
3,
12
],
"text": [
"There is a theoretical planetary system in which a planet could possibly switch stars at random in a figure eight-like pattern, but it’s a hectic system because it’s constantly changing gravitational forces and would likely end up with the planet being ejected or being incinerated because it flew into one of the stars. If that kind of system existed, it would really only be stable for a few million years.",
"It appears that [some figure 8 orbits are stable](_URL_2_):\n\n > We present the results of a numerical search for periodic orbits with zero angular momentum in the Newtonian planar three-body problem with equal masses focused on a narrow search window bracketing the figure-eight initial conditions. We found eleven solutions that can be described as some power of the “figure-eight” solution in the sense of the topological classification method. One of these solutions, with the seventh power of the “figure-eight”, is a choreography. We show numerical evidence of its stability.\n\nThere are [many other exotic 3-body solutions](_URL_1_) that are long-lived and may be stable. One fun one is called the [Sitnikov problem](_URL_0_), where a planet oscillates up and down right in the middle between two stars that orbit each other. This also seems to be a stable solution.",
"No, there are no such stable orbits. (I notice lots of people don't seem to understand what \"stable\" means. A pencil balanced on its point is not stable, even though there is an equilibrium position there.)\n\nA couple of people have pointed out that there are some possible figure-8 orbits in which a group of objects of identical mass all move together in the same orbit. That's not what the OP is asking about. He/She wants a small planet in a figure-8 around two big stars. This is not stable."
]
}
|
[] |
[] |
[
[],
[
"http://www.scholarpedia.org/article/Sitnikov_problem",
"https://arxiv.org/abs/1303.0181",
"https://arxiv.org/abs/1312.7002"
],
[]
] |
|
mukff
|
First question to AskScience. How much of the universe can't we see due to the extreme distances?
|
My title refers more specifically to the light from distant objects traveling to us, not so much about the light itself dissipating.
I understand the basic premise of the limitation light from super far away galaxies/stars (anything farther away in light years than ~Earth's age mean we can't observe them).
So my question is, do we have an idea of how much of the universe we can't see?
|
askscience
|
http://www.reddit.com/r/askscience/comments/mukff/first_question_to_askscience_how_much_of_the/
|
{
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"c33yjl9",
"c342l6d",
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"c342l6d"
],
"score": [
15,
2,
15,
2
],
"text": [
"The furthest object we can see would be cosmic microwave background radiation. As we look far away, we also look at the past. Thus, we see younger and younger objects as we look further. We see young galaxies, and even the first galaxies forming. Eventually, we see how the Universe looked like when it was just a bunch of hydrogen and helium gas. And if we look even further, we see the so called surface of last scattering. Behind this surface, the Universe is so young, which means that is so hot, that neutral hydrogen cannot form. It's ionized, the electrons and protons are seperated. It's a plasma. Light can't penetrate plasma, that's why this is (effectively) the earliest, farthest thing we can see. If we could see neutrinos as easily as photons, we could look even a little further than that.\n\nIt's about 46 billion light years away, and it was emitted 13.7 billion years ago. Sounds strange? Not if you take into account the expansion of space. The point where that radiation was emitted moved away from us after the emission, so it's further apart than it was at the time of emission.\n\nIf you are asking what *percentage* of the Universe we can see, then I have no answer for you. But we know that the Universe is at least 250 times bigger than the observable Universe, quite possibly even infinite.",
"The universe is (to the best of our knowledge) infinite in size, so the part we can't see is also infinite in size.",
"The furthest object we can see would be cosmic microwave background radiation. As we look far away, we also look at the past. Thus, we see younger and younger objects as we look further. We see young galaxies, and even the first galaxies forming. Eventually, we see how the Universe looked like when it was just a bunch of hydrogen and helium gas. And if we look even further, we see the so called surface of last scattering. Behind this surface, the Universe is so young, which means that is so hot, that neutral hydrogen cannot form. It's ionized, the electrons and protons are seperated. It's a plasma. Light can't penetrate plasma, that's why this is (effectively) the earliest, farthest thing we can see. If we could see neutrinos as easily as photons, we could look even a little further than that.\n\nIt's about 46 billion light years away, and it was emitted 13.7 billion years ago. Sounds strange? Not if you take into account the expansion of space. The point where that radiation was emitted moved away from us after the emission, so it's further apart than it was at the time of emission.\n\nIf you are asking what *percentage* of the Universe we can see, then I have no answer for you. But we know that the Universe is at least 250 times bigger than the observable Universe, quite possibly even infinite.",
"The universe is (to the best of our knowledge) infinite in size, so the part we can't see is also infinite in size."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
1ebhbo
|
Could an object orbit the moon at a really low height? (Like 500 ft, assuming it doesn't run into mountains)
|
[This picture](_URL_0_) goi me thinking about it. The moon has no atmosphere, so there's no air resistance. So could an object, going fast enough, orbit the moon at a low height?
EDIT: If the mountains are in the way, hypothetically bulldoze the moon's surface flat.
|
askscience
|
http://www.reddit.com/r/askscience/comments/1ebhbo/could_an_object_orbit_the_moon_at_a_really_low/
|
{
"a_id": [
"c9yl9q7",
"c9yq056",
"c9zj67l"
],
"score": [
20,
13,
3
],
"text": [
"Yes it could. Orbital speed at the Moon's surface is around 1.68km/s, so it wouldn't even have to be traveling that fast.\n\nMountains would of course get in the way.",
"Not for long. Objects in low orbit are more susceptible to gravitational anomalies in the object they orbit.\n\nAlso, the earth's gravity makes lunar orbits unstable in the long run. ",
"It opens up opportunities for a novel form of transportation on the moon: You could have a \"maglev\" that simply accelerated the train to orbital velocity (3758 mph or 1680 m/s), and then the train would float over the surface of the moon till it reached the other half of the track, which decelerates it. Going at that speed, you could get to the other side of the moon in just under an hour\n\nEdit: At that speed, mountains being in the way is a self-solving problem. You just shoot trains at them at orbital velocity until the mountains are no longer in the way"
]
}
|
[] |
[
"http://www.nuffieldfoundation.org/sites/default/files/images/Orbits%20of%20satellites%20and%20moons_782.jpg"
] |
[
[],
[],
[]
] |
|
7yj73o
|
Do Lagrange points exist for planets in elliptical orbits?
|
If so, how are they different than the mostly-circular orbit of Earth? Is there some cutoff point where the orbit is too elliptical to have langrange points?
|
askscience
|
https://www.reddit.com/r/askscience/comments/7yj73o/do_lagrange_points_exist_for_planets_in/
|
{
"a_id": [
"duh5y27",
"duhe3kt"
],
"score": [
3,
7
],
"text": [
"All 2-body systems have Lagrange points. Their location is dependent on the masses of the two objects\n\n[Here](_URL_0_) is a wonderful paper on Lagrangian points made by NASA.",
"All planets have elliptical orbits. Newton’s laws mandate it; Earth is no exception. Something having an elliptical orbit has no effect on wether or not it has Lagrange points. However, most objects with very elliptical orbits probably don’t have them because objects that have very elliptical orbits are usually small, have long orbits, and/or are very far away (in reference to something like the sun). All of which do have an effect on if something has Lagrange points."
]
}
|
[] |
[] |
[
[
"https://map.gsfc.nasa.gov/ContentMedia/lagrange.pdf"
],
[]
] |
|
2sov2b
|
how do credit card companies provide refunds for scams?
|
I was subject to misleading advertising the other day, where I had to pay an additional 500% after the original payment, which was written in small print on the site. Of course, the company was adamant that I couldn't get a refund.
Luckily, I had paid with a credit card, and within 4 hours of contacting the credit card company they had successfully managed to get a refund directly from the site itself. How do they achieve this?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2sov2b/eli5_how_do_credit_card_companies_provide_refunds/
|
{
"a_id": [
"cnrih6n",
"cnrk07f",
"cnrkndc"
],
"score": [
2,
2,
2
],
"text": [
"I guess it's a combination of insurance and the weight of all of their lawyers and legal teams. They can come down on the company with enough aggro that it's cheaper to just do the refund, rather than pay to fight a legal battle.",
"OP, what was the site and/or purchase you made? I'm legitimately curious as to what business could (or would) do that.",
"It wouldn't be a case of them arguing with the company to give you a refund, they would just click a button on their system to reverse that transaction, against the scamming company's wishes if it wants to.\n\nOf course, the company is quite unlikely to challenge your credit card company over doing that, it would cost a lot more in legal fees."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
4cb55d
|
what are cuticles for, and why do people "push them back"?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4cb55d/eli5_what_are_cuticles_for_and_why_do_people_push/
|
{
"a_id": [
"d1gkaut"
],
"score": [
4
],
"text": [
"They protect the skin adjacent to the nail from debris and microbes. People push them back because they believe it looks better, but it does carry an increased risk of infection."
]
}
|
[] |
[] |
[
[]
] |
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