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255cfu
|
what happens if someone is bit by a coral snake in the united states?
|
I understand that there is no more production of Coral Snake anti-venom in the United States, what is the standard procedure for Coral Snake bites?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/255cfu/eli5what_happens_if_someone_is_bit_by_a_coral/
|
{
"a_id": [
"chduavo",
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"score": [
2,
2
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"text": [
"There hasn't been production of any coral snake antivenin for over ten years, and supplies are dwindling. I think the standard procedure is to use what little remains in inventory.\n\nWhat happens after those run out is anybody's guess.",
"These days, I think you just die. Sadly, pharmaceutical companies don't make any money on coral snake anti-venom. It's very expensive to make and there are only ~25 cases a year, so there is also very little demand."
]
}
|
[] |
[] |
[
[],
[]
] |
|
65dq28
|
is there any way to test a nuclear weapon without without being detected?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/65dq28/eli5_is_there_any_way_to_test_a_nuclear_weapon/
|
{
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"dg9eut1",
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3,
6,
2
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"text": [
"You can detect a nuclear explosion with a seismograph, even if you had a magic nuke that didn't release incredible amounts of light and heat visible to every satellite in the area.",
"Not that is publicly known of. Underground explosions create seismic waves, explosions in air create light flashes and blast waves and release radioactivity, explosions in space create light flashes. All those can be detected.\n\nIf any state has a way to do an undetectable nuclear test, which is very unlikely, they've kept it secret.",
"There are \"Deep Nuclear Explosions\" which are very deep underwater ( < 2,000 ft underwater). At that depth there's nothing visible on the surface. The huge gas cloud from the explosion dissipates at that depth, so there's nothing visible on the surface. It leaves no trace at the surface but hot, radioactive water rising from below. This leaves a small patch of evidence in a massive ocean. Can be very hard to detect."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
fh107x
|
when light passes through a transparent object, do the photos simply pass between the atoms or are they absorbed by the atoms and re-emitted?
|
When it comes to light passing through objects I wasnt sure if the light actually passes between the atoms or if it is absorbed by the atoms and is then emitted by the atoms in sequence until its passes through it entirely. Why else would lights speed slow in various mediums?
Similarly, when light is reflected, are the photons actually bouncing off the atoms, or are they being absorbed and emitted back at the same angle?
If they are, why do atoms shoot the photons off at the same angle opposed to a random one?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/fh107x/eli5_when_light_passes_through_a_transparent/
|
{
"a_id": [
"fk85u79"
],
"score": [
47
],
"text": [
"So, it's sorta pretty weird. We have to remember that light is also a wave, and the way it travels through matter is wave-like more than it is particle light.\n\nIf you aren't familiar, waves obey the property of superposition - that is that the height of two interacting waves at any given point in space is literally the sum of the heights of the two contributing waves at that point in space.\n\nSo, light is a wave in the electromagnetic spectrum. It has a speed and it has a wavelength.\n\nWhen this wave interacts with matter, the changing electromagnetic field causes the electrons in matter to begin oscillating back and forth.\n\nWell, oscillating charged particles produce their own electromagnetic field. This electromagnetic field interacts with the electromagnetic field of the incoming light.\n\nBy superposition, these two waves are added together. The result is... sorta not intuitive. What you end up with is a changing electromagnetic field that travels at a speed that is neither the speed of light nor the speed of the electrons. Please watch [This Video](_URL_1_) for a visual understanding of how that is possible. \n\n[Here is a video](_URL_0_) that gives the more detailed explanation of the question you are asking. The first video is geared towards a visual understanding, the second video is geared towards an actual explanation."
]
}
|
[] |
[] |
[
[
"https://www.youtube.com/watch?v=CUjt36SD3h8",
"https://www.youtube.com/watch?v=EIqKG5TiSYs&t=6s"
]
] |
|
5499cl
|
Can brain damage alter what a person sees?
|
I know that our senses (eyes, ears, etc) just relay information to the brain, and the brain is what actually does the sensing (seeing, hearing, etc). So can damage to a specific part of the brain alter how the brain understands the data from our senses? Moreover, is it possible to change how the brain interprets the info from the eye for example, so as to create images that are not actually there?
|
askscience
|
https://www.reddit.com/r/askscience/comments/5499cl/can_brain_damage_alter_what_a_person_sees/
|
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2
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"text": [
"Yes.\n\nMost often this will be \"negative\" phenomena—a loss of some aspect of perception. This can be loss of depth information (*astereoscopy*), loss of color (*achromatopsia*), loss of movement continuity (*akinetopsia*), loss of recognition of objects (*visual agnosia*, of which *prosopagnasia* for faceblindness is one particularly salient example), or problems with judging size/shape (*metamorphopsia*).\n\nTo the extent brain damage may cause seizures affecting the occipital, parietal, and temporal lobes, positive phenomena ranging from gyres of color to fully-formed hallucinations of people can occur.",
"/u/adoarns gave plenty of examples. I just want to point out that the sensory organs do a lot of processing even before information is sent to the brain. There are several layers of cells in front of photoreceptors that transform the signal in various ways, for example.",
"The brain can definitely end up creating images that aren't there in the proximal stimulus (what hits the retina), and this is part of normal perception (proper interpretation of, say, depth, as well as illusions, and all sorts of top-down and multisensory determinants of perception). But as for brain damage making you see things not in the eye signal, sure. Hallucinations can be caused by damage at various stages of sensory processing. If the damage is due to deafferentation (not getting signals from the eye or not as much, for example) you might get simple hallucinations like in Charles Bonnet Syndrome, prisoner's cinema, or Ganzfeld-style hallucinations. If it occurs later/deeper into processing, hallucinations can occur that are even more complex. This can happen due to stroke damage but also seizures and migraines and toxins and obviously drugs (hallucinogens change how the brain processes / constructs sensory info together).",
"Optometry student here. One of the most common forms of vision alteration from brain damage is visual field loss due to stroke. \n\nAt the optic chiasm near the front of the brain, neurons cross over so that visual signals from the right visual field (temporal retina of the left eye and nasal retina of the right eye) all travels in the left side of the brain back to the occipital lobe, and left visual field travels through the right brain. Our understanding of the anatomy of the visual pathway means that we can often localize the area of damage based on the pattern of visual field loss. \n\nStrokes that occur behind the optic chiasm that affect the visual pathway will cause varying degrees of vision loss in the visual field of the opposite side. However, this doesn't appear to the person as blackness, just like areas outside your field of vision aren't perceived as black. They're just not perceived. So the person may notice that they bump into things on one side or miss cars on that side while driving. People who lose vision on the right side can have difficulty reading because they don't see where the eyes need to look to find the next word. \n\nBrain tumors can have a similar effect. Since the pituitary gland sits right above the optic chiasm, pituitary tumors can also cause visual field loss. Remember that information from the nasal retina, which corresponds to the temporal visual field, cross es to the other side of the brain here. So when a pituitary tumor grows it pushes down on these nerve fibers and causes visual field loss on both temporal sides. \n\n",
"Sure. Dramatic examples are offered by split brain individuals. They can see something, know what it is, and can't name it because the two hemispheres can't communicate. So right brain and left brain processes are unable to exchange info."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
|
3n29l6
|
Why were old ads so verbose?
|
This might be a bit of an off-the-wall question, but I've always sort of wondered why old ads (like [this candy ad from 1925](_URL_0_)) sometimes feature multiple paragraphs of text, which you'd never see in a modern ad. Were we just bad at advertising back then, or maybe is related to changing media / media consumption? Or something else?
Thanks!
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3n29l6/why_were_old_ads_so_verbose/
|
{
"a_id": [
"cvkcih6"
],
"score": [
20
],
"text": [
"Having briefly been a PR practitioner I might be able to point to a few things, some of which might challenge the basis of your question, some of which will help answer it.\n\n1. Were we just bad at advertising back then?\n\nA little bit. Yes. Or at the very least it was less sophisticated. The first person to really go out and analyze what was effective in advertising was George Gallup who worked for Young and Rubicam Advertising in the 1930s. Gallup would go on to be famous for the Gallup opinion polls which still bear his name but in the 1930s he really started to do some of the earliest research for what worked in marketing.\n\n*That being said* some of the most powerful men in advertising in the mid century who had access to that research reached the opposite conclusion that you have here. David Ogilvy in *Ogilvy on Advertising* noted that, for instance, that \"editorial\" style ads were among the most effective. That long copy appeared to be more effective than short copy.\n\n2 . I'd challenge your assumption here that this sort of thing isn't done any more. The \"advertorial\" is a persistently popular form of advertisement. The OED lists the first use of the term as going back to 1914. It remains popular today.\n\n3 . Shifting media is important, but so is the nature of the marketing/advertising industry. The first full-service PR agencies arrived after the first ad agencies, and they are still a misunderstood beast. PR in the popular imagination is sometimes thought of as crisis management in preserving public opinion, or some sort of \"spin-doctoring\" about a controversial subject a la *Thank You for Smoking*.\n\nPR also includes quite a lot of consumer PR, which might be extremely simplified into describing the art of taking a company's news, framing it in a positive light in the form of a press release and then getting that reprinted as actual news in the media.\n\nThe result is that advertising has in a way been \"freed\" to separate some of that audio-visual stuff from the longer form stories.\n\nIf Oh Henry! were doing this today instead of hiring an ad agency to write about how \"Chicago women\" discovered sliced Oh Henry! they might hire a PR agency to set up an actual event at a Chicago food fair where young Chicago foodies could try sliced Oh Henry! candies. The PR agency, in turn, would give selected writers privileged access to the event to write about and produce a press release about the food fair and how much everyone loved sliced Oh Henry! which would be sent to a broader range of media. That event could then feature in broader advertising.\n\nThe Pepsi Challenge is a good example of that process where real event-- > media coverage-- > advertising copy.\n\nSource wise I think your best bet would be to read some of the classics on this like the books of David Ogilvy, or Luke Sullivan's \"Hey Whipple, Squeeze This\"."
]
}
|
[] |
[
"https://www.flickr.com/photos/typetive/6384269131"
] |
[
[]
] |
|
2yzcxi
|
why do some transactions process in half a second, and others take 3 days?
|
It drives me fucking nuts sometimes that I'll wake up on Monday morning and there's $200 less in my bank account than I thought. I'll go back through my bank account and there will be a bill I paid on thursday last week that just processed. On the other hand, I filled up my car on sunday and that appeared immediately.
Here's the part that **really** confuses me. I can pay a phone bill online using my card and it will inform me it takes a full 24 hours to process. I check my bank account and my bank account has deducted the money instantly, but when I check my phone bill online it hasn't deducted the money. On the other hand, I top up my public transport card and I can use that topped up money straight away, but it hasn't been deducted from my bank account.
This is the digital age, why doesn't this all work pretty much the same? :/
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2yzcxi/eli5_why_do_some_transactions_process_in_half_a/
|
{
"a_id": [
"cpex8yb"
],
"score": [
2
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"text": [
"How banks work. What's easier. Bank A: Send me $2.37 for Joes purchase. Bank B: send me $3.5 for Bibs purchase. Thousands of times a second. \n\nOr\n\n\nEnd of day: Bank A: Your clients owe me 3 billion. Bank B: your clients owe me 2 billion, so I'll just give you 1 billion"
]
}
|
[] |
[] |
[
[]
] |
|
4ii6fl
|
Are we certain that no humans lived in North America prior to crossing the Bering Strait?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4ii6fl/are_we_certain_that_no_humans_lived_in_north/
|
{
"a_id": [
"d2yc84d"
],
"score": [
7
],
"text": [
"Not to discourage you from posting here, but you may find more people ready to comment on this question by crossposting to r/AskAnthropology"
]
}
|
[] |
[] |
[
[]
] |
||
c1lrkb
|
Do astronauts have to wear sun cream in space i.e Like on the ISS?
|
They're closer to the sun so you'd think so right? It's also bugging me.
|
askscience
|
https://www.reddit.com/r/askscience/comments/c1lrkb/do_astronauts_have_to_wear_sun_cream_in_space_ie/
|
{
"a_id": [
"ergh1dx"
],
"score": [
7
],
"text": [
"They're not really any closer to the sun: the ISS is in a low earth orbit, only 400km above sea level. That's on the order of one thousandth of the distance to the moon, or one millionth of the distance to the sun.\n\nIt's true that they're outside of the atmosphere, so there's a lot more UV as none of it gets absorbed by e.g. the ozone layer (which is about 20km above sea level). But UV radiation really is a problem only if you're naked outside. Any piece of wall, glass or clothing will shield UV radiation quite efficiently, so it isn't a big problem.\n\nAstronauts are exposed to other types of ionizing radiation though, which are harder to shield against"
]
}
|
[] |
[] |
[
[]
] |
|
euaqe8
|
why does earth have no ring even after exterior body colliding with earth and launching all the debris in space?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/euaqe8/eli5_why_does_earth_have_no_ring_even_after/
|
{
"a_id": [
"ffnlktk"
],
"score": [
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"text": [
"rings around a planet are really unstable, stuff too close could probably burn up and stuff too far would clump together and make something bigger. The earth probably had a ring when something crashed into it. The 4 gas giants have rings but those are mostly made of ice and ice would melt if it was in orbit around earth. \n\nYou can look up the Roche limit or Roche radius. This fine line around a body is where things break up because of the tidal forces acting on something orbiting that body.\n\nTo explain this, gravity around a body has an exponential inverse graph. So it starts off very high and dramatically reduces the further away you go from a body.\n\nThe Roche limit is where that curve slopes down the fastest (kinda). So it's the part of the curve where you see the most *curve*. [Something like the graph here](_URL_0_)\n\nYou can see that at that point, a tiny increase in distance results in a dramatic drop in gravity. So take for example the moon. The moon is currently far enough away so that it stays in orbit and doeant fly away from earth. But what if it was at that point on the graph? \n\nOne end of the moon would have a very strong gravity acting on it and the other end would have very little gravity and more tendency to fly away from earth. So what happens? The moon would stretch apart and break into lots of pieces. \n\nTwo things will happen after that, the pieces at the Roche limit and below will stay there and form that ring and continue to orbit earth and the pieces past the Roche limit will coalesce again and make another moon. \n\nWhen pieces are too small, the tidal forces at the Roche limit won't really have an effect on them because they are too small. \n\nSo what most likely happened when something hit earth, was that it flew far away from the earth and the little gravitational pull from each of these small pieces come and pull each other together to form the moon which is how things in space coalesce. The moon is said to be much closer to earth millions of years ago than it was today. So it most likely just picked up whatever rubble it came across on its journey away from earth. And things close to earth were a negligible amount and most like burned up in the atmosphere at some point or just the effects of the sun being a deadly lazer"
]
}
|
[] |
[] |
[
[
"https://imagine.gsfc.nasa.gov/features/yba/M31_velocity/lightcurve/gravity_example.html"
]
] |
||
97kflt
|
can someone explains what happens to meteors and meterorites?
|
I know the difference between the two is that the former is burned in the air whereas the latter hits Earth, but what exactly happens to them? As they burn up, they get smaller, but what happens to that burnt up debris? Does it get scattered in the atmosphere; if it does, is it subject to some aerosol osmosis thing? For the small bits that do hit the Earth, does it dig itself underground at the impact site? If it hits ocean water, what happens to the hot parts; does it diffuse out or immediately evaporate until the less hot parts are left to sink? Would a large meteorite still be large after an ocean impact, or would it be shattered?
What happens to meteors and meteorites?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/97kflt/eli5_can_someone_explains_what_happens_to_meteors/
|
{
"a_id": [
"e48utub",
"e48v3g7"
],
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2,
3
],
"text": [
"You basically got it right, most small ones burn up and become dust in the atmosphere, some of which does aerosolize. I always recommend _URL_0_ if you want to see how PM2.5 spreads out across the planet.\n\nThe larger ones that actually make it to the ground (which is really rare) are mostly recovered in this day and age, they don't dig themselves too far underground, the top soil will be thrown clear.\n\nIf it hits the ocean it cools quickly then sinks, hitting the water at high speed is not that different from hitting concrete, so if it were to break it would likely break, but could be strong enough to survive.",
"Small ones that survive the trip slow down enough that they land like any rock. They may shatter, or plunk down in one piece if they're sturdy enough.\n\nBigger ones don't lose much speed and carve out craters if they hit land. Most of them fall in the oceans, where they sink to the bottom.\n\nThey're really not that hot when they land, the outside is scalded from the ride but the inside is deep-space cold.\n\nYou can find the small ones laying around if you're lucky. They have distictive smooth and blackened exteriors that look different from generic rocks. Some have enough iron to stick to magnets.\n\nThe ones that get pulverized in the atmosphere just sprinkle down as a fine dust, along with all the other pollen and dirt that covers everything."
]
}
|
[] |
[] |
[
[
"earth.nullschool.net"
],
[]
] |
|
16b63u
|
Is it true that the effect of fanning yourself (as in with your hands) is actually a net INCREASE in body temperature?
|
I heard this on the radio today, however the guy wasn't a scientist, he was just reiterating something he had heard. He basically said that when you fan yourself (such as on a hot day with a piece of paper etc) you actually increase your body temperature due to what he referred to as a "fundamental law of physics"
|
askscience
|
http://www.reddit.com/r/askscience/comments/16b63u/is_it_true_that_the_effect_of_fanning_yourself_as/
|
{
"a_id": [
"c7uk1dj"
],
"score": [
5
],
"text": [
"He was bsing.\n\nMoving your hand generates a small amount of heat. Fanning yourself removes a reasonably large amount of heat. I suspect the net effect is normally cooling since you don't use much energy moving your arm, but it would depend on lots of factors like humidity, sweating, arm weight, temperature etc.\n\nWhat he had heard was probably on net entropy increases. On net entropy doesn't change. But by pushing cold air onto your face you can reduce your temperature."
]
}
|
[] |
[] |
[
[]
] |
|
adjulc
|
How did the invention of hangul affect the spread of the moveable type in Korea?
|
The Korean moveable type seems to lack the transformative social impact of Gutenberg's invention despite appearing earlier, and it would appear that the sheer number of Chinese characters was the main limiting factor. Wikipedia has this to say on how the invention of hangul affected printing in Korea:
> A potential solution to the linguistic and cultural bottleneck that held back movable type in Korea for 200 years appeared in the early 15th century—a generation before Gutenberg would begin working on his own movable-type invention in Europe—when Sejong the Great devised a simplified alphabet of 24 characters (hangul) for use by the common people, which could have made the typecasting and compositing process more feasible. But Korea's cultural elite, "appalled at the idea of losing hanja, the badge of their elitism", stifled the adoption of the new alphabet.
> A "Confucian prohibition on the commercialization of printing" also obstructed the proliferation of movable type, restricting the distribution of books produced using the new method to the government. The technique was restricted to use by the royal foundry for official state publications only, where the focus was on reprinting Chinese classics lost in 1126 when Korea's libraries and palaces had perished in a conflict between dynasties.
Did elitism and cultural hangups completely stifle the development of mass printing in hangul? Were there major efforts within the gentry to introduce the moveable type to the wider society? Did either technology actually contribute to widespread literacy in Korea? The introduction of modern printing in the 19th century obviously didn't kill hanja right away, so I'm curious whether hangul ever managed to live up to its potentials with the earlier moveable type. Thank you very much in advance!
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/adjulc/how_did_the_invention_of_hangul_affect_the_spread/
|
{
"a_id": [
"eef8dhb"
],
"score": [
3
],
"text": [
"Hangul is the alphabet created by King Sejong.\n\n & #x200B;\n\nQ. What is the purpose of making Hangul?\n\nMajor. For the people.\n\nMinor. Hangul is easy to learn Chinese characters.\n\nMinor. It was a useful tool for the middle class in real administration(strengthening the system).\n\nBasis: When creating Han-gul, the way intellectuals write is by using a brush. However, Hangul does not need expensive tools such as brush, ink, and paper. At the extreme, Hangul can be written using twigs. This means that Han-gul was first made on the premise that it did not use a brush.\n\n & #x200B;\n\nQ. What is the perception of Han-gul by the people of the time?\n\nThe nobility of Joseon had a tendency to despise sentences written in Hangul. BUT, Hangul itself was a feat of the dynasty(In Joseon and modern Korea, King Sejong is extremely respected.). With the exception of a few exceptions, nobles and royal families (including women) could use Hangeul. The nobles used Chinese characters to write official documents, and Han-gul to write private documents (letters, etc.).\n\n & #x200B;\n\nQ. Who used Hangul?\n\nMajor. noble woman.\n\nMinor. middle class.\n\nMinor. the use of young aristocrats to learn Chinese characters easily.\n\nMinor. military code.\n\n & #x200B;\n\nQ. Why couldn't the printing press be used widely in Joseon?\n\nThis is a complicated problem. First of all, we need to know the purpose of the development of printing.\n\nGutenberg's printing came from a commercial motive. But printing in Joseon was developed for policy purposes to disseminate their studies. Joseon strongly believed that commercial development was the act of destroying the nation. Joseon despised the merchant. The ruling class of Joseon was absorbed in metaphysical philosophy. For them, books meant only academics, philosophy and history. All other books (fiction books, etc.) were considered dirty books that disturb society.\n\n & #x200B;\n\nThe ruling class of Joseon had an paranoid record of history. They have copied history books three to five times and set up data centers throughout the country in preparation for losing them due to war or fire. Thanks to their paranoids to preserve history, Korea has an overwhelming amount of Joseon records despite countless wars and looting. South Korea is not worried about the lack of data about Joseon, but about too much data. According to scholars, the documents written by Joseon's secretariat are expected to take 100 years to translate.\n\n & #x200B;\n\nAnother problem is that copper is needed to make a metal printing press, but copper has little yield in Joseon. Most have to import from Japan. As mentioned above, however, Joseon despised commerce and curbed international trade. The state is the only one who can afford this cost. And even if a civilian can afford it, his books will be censored by the state, and his life will be ruined if the book disturbs the spirits of the nobility. This vicious circle led to the monopoly on printing and publishing by the state. As a result, unlike the West, where metal type printing machines rapidly spread to the private sector, Joseon went to monopolize metal type printing machines and instead to solidify medieval order. Therefore, did the development of the printing press contribute to the eradication of illiteracy? The answer to is no."
]
}
|
[] |
[] |
[
[]
] |
|
2t1lt7
|
Given the theory of space-time in general relativity, does time act differently where there is more or less gravitational effect?
|
I admit even with the limited grasp I have on physics this doesn't seem to fit... Haven't properly educated myself mathematically, though in the past few years I've been educating myself through books and documentaries on various theories of physics.
|
askscience
|
http://www.reddit.com/r/askscience/comments/2t1lt7/given_the_theory_of_spacetime_in_general/
|
{
"a_id": [
"cnuvduw",
"cnv0jsf"
],
"score": [
16,
7
],
"text": [
"Time slows down for an observer under the effect of gravity. The stronger the gravitational field, the slower time passes.",
"Whenever this topic comes up, I recommend the book Einstein's Dreams. It's a small book of fictional short stories that explore scientifically-accurate scenarios where time flows differently due to differences in gravity. It's not just good sci-fi writing, it also helps make this particular GR concept more intuitive."
]
}
|
[] |
[] |
[
[],
[]
] |
|
2kfecl
|
why do high school and college football teams have marching bands, but nfl and other sports don't?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2kfecl/eli5_why_do_high_school_and_college_football/
|
{
"a_id": [
"clksnif",
"clkt1fv",
"clkvwio"
],
"score": [
3,
2,
3
],
"text": [
"The Ravens still have a band, but its not common. It's a tradition for Baltimore, after the Colts left the band stayed behind and represented the cities passion for the football team. When the Ravens came they kept up the tradition.",
"High school and college students are willing to spend 15+ hours a week for no pay practicing and rehearsing. I couldn't imagine the NFL moving any of their precious funds towards having bands.",
"Because those teams belong to schools, and schools have music programs. The NFL does not contain any music schools."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
1wiebc
|
What kind of beer, if any did pirates drink?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1wiebc/what_kind_of_beer_if_any_did_pirates_drink/
|
{
"a_id": [
"cf2hixc"
],
"score": [
6
],
"text": [
" Only recently has beer been able to travel well. IPA , India Pale Ale, was the first beer that could survive the trip from England to India. I believe that the XXX mark designated a beer that could travel. That is where Double Diamond got their Logo. Beer is also very bulky and has a low alcohol content. Overproof rum was the drink of choice in the lower decks . It was cheap and did the job.The grog ration was very important, would be hoarded for special events. Sailors ashore is another matter, to this day sailors ashore are famous for getting in trouble."
]
}
|
[] |
[] |
[
[]
] |
||
1u2p4u
|
Why are horizontal and vertical motion (of particles) independent?
|
I've taken it on faith since it was taught in secondary school but never thought about why it was true. It makes intuitive sense, there's no reason why should they affect each other in the first place, but I was asked this by a family member recently and couldn't really satisfy him with an answer.
I did try to use the example of firing a gun horizontally and dropping a bullet at the same time, leading to them both hitting the ground simultaneously since the only force acting on them is gravity, but that wasn't good enough either apparently.
|
askscience
|
http://www.reddit.com/r/askscience/comments/1u2p4u/why_are_horizontal_and_vertical_motion_of/
|
{
"a_id": [
"cedz25t",
"cee44ks",
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],
"score": [
5,
4,
3
],
"text": [
"We define the geometry of our coordinate system such that this is true. In the Cartesian coordinate system the x (horizontal) and y (vertical) directions are orthogonal (at right angles to each other). This means any force pointing along x or y (gravity points only along negative y) will only affect motion in that direction, and not the other. This simplifies the calculations a lot, and is why we generally use this system.\n\n\nIf you choose a different coordinate system, however, all bets are off. For example, using a polar coordinate system would make things much more complicated for planar motion. (But this actually simplifies many other problems in physics where the Cartesian coordinates are inappropriate). \n",
"Okay, there's a lot of math \"proof\" (Called Noether's theorem) behind what I'm about to say, and I can discuss it if you want, I just don't know what your background is. \n\nIf the laws of physics are the same along any one direction, there will be \"inertia\" along that direction. Inertia means that momentum, a measure of how \"hard\" something is moving\", will stay constant, unless acted on by some force.\n\nSo when physics stays the same in the horizontal directions (because gravity doesn't pull horizontally) that means that horizontal motion along two *independent* (read: perpendicular) axes is independent. But physics \"changes\" along the vertical axis because there's a force of gravity (In the Newtonian sense, at least). So momentum isn't conserved along that axis. The ball goes up and comes down. \n\nBut because we can break each axis up separately, mathematically, then we can show that momentum is conserved independently along each axis, or not, depending on the forces along each axis or not.",
"The independence of horizontal (x) and vertical (y) motion only works if the force in one direction does not depend on the motion in the other. This is OK for gravity problems, where the vertical force is mg, and the horizontal force is zero, independent of the x and y motion. \n\nIt fails, for example, if there is nonlinear friction (proportional to the square of the velocity). In that case, because v^(2) depends on both vx and vy, each component of the force depends on the motion in the other direction. This is not an unrealistic example; IIRC, air resistance behaves like this."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
7zan5a
|
why do large airports all seem to have news station branded convenience stores, and why do these types of stores seem limited to airports?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7zan5a/eli5_why_do_large_airports_all_seem_to_have_news/
|
{
"a_id": [
"duml0bk"
],
"score": [
6
],
"text": [
"Some years ago, Hudson News became a chain if newsstands in airports selling magazines, newspapers, and the like. They expanded to become convenience stores.\n\nSo their top competitor decided to copy the \"news\" theme and made a deal with CNBC.\n\n_URL_0_"
]
}
|
[] |
[] |
[
[
"https://tedium.co/2016/08/16/airport-stores-named-after-tv-networks/"
]
] |
|
2ts96f
|
why is it common for american houses to have issues with carbon monoxide?
|
As long as I know in Europe it isn't an issue except for indoor car parks, garages etc.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2ts96f/eli5_why_is_it_common_for_american_houses_to_have/
|
{
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"co1v5ew",
"co1vjsu"
],
"score": [
2,
5
],
"text": [
"It is common for American houses to have natural gas furnaces, water heaters, ranges and ovens. If you have any of those in your home in Europe you are equally at risk. ",
"I do not think that carbon monoxide issues are all that common in America. although, on occasion you will hear about an unintentional poisoning and subsequent death(s). The problem with carbon monoxide is that it is odorless and will put a person to sleep and then effectively suffocate them. Yes, you can shut your self in a garage (car park) and leave your car running and you may kill yourself. The real danger and concern is a in-house heater or possibly water heater, while in use, leaking carbon monoxide into the living environment and being odorless, going undetected and killing everyone in the environment. We have carbon monoxide detectors specifically for this purpose. Older homes, (plus 30 years) with older equipment are the most concerning."
]
}
|
[] |
[] |
[
[],
[]
] |
|
33ylyt
|
why don't they enclose prisoner cells within a faraday cage?
|
With how big and serious of a problem prison cell phone use can be: why have we not shielded prison cells (only cells, not the whole prison) from incoming and outgoing cell phone frequencies? It would save lives of many people and disrupt criminal money flow and operations on the outside.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/33ylyt/eli5_why_dont_they_enclose_prisoner_cells_within/
|
{
"a_id": [
"cqpkqhu"
],
"score": [
7
],
"text": [
"Some prisons have been known to use jammers to prevent cell-phone use, and that's a huge amount cheaper and easier than is faraday caging the whole area.\n\n"
]
}
|
[] |
[] |
[
[]
] |
|
iigzf
|
How come the wind keeps putting out my lighter, but does nothing to the cigarette once it's lit?
|
askscience
|
http://www.reddit.com/r/askscience/comments/iigzf/how_come_the_wind_keeps_putting_out_my_lighter/
|
{
"a_id": [
"c240nxy",
"c2411tp"
],
"score": [
10,
2
],
"text": [
"For a few reasons.\n\n1. Solid verse gaseous/liquid fuel. The fuel from your lighter is easily blown and dispersed, which greatly affects its ability to burn. Your cigarette is a solid fuel, and isn't blown away .\n\n2. Flame verse ember. Flames are sensitive to wind, they're easily extinguished. A match is harder to put out than a lighter because here, the solid fuel remains in place. This is also a function of #1. The ember in your cigarette is not susceptible to air currents, at least not at the level you'd see in your typical wind. Embers are actually encouraged by air movement, it brings fresh fuel (Oxygen) to the party, thats why the tip glows brighter when you inhale. If you provided the optimal fuel:air mix, you could actually cause robust enough ignition to generate flames on the tip of your cig.\n\n",
"I am not an expert but Saltpeter aka [Potassium nitrate](_URL_0_) is one of many additives in your product and this one helps maintain the burn."
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Potassium_nitrate"
]
] |
||
1e064e
|
why do stadiums cost much more to build today than they did ten years ago?
|
According to [this page](_URL_0_) when M & T Bank Stadium was built in 1998, it cost $226 million while MetLife Stadium cost $1.6 billion in 2009. Sun Life Stadium's (planned and rejected) renovations were even slated to cost $350 million. What is the reason for the drastic increases in costs?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1e064e/eli5_why_do_stadiums_cost_much_more_to_build/
|
{
"a_id": [
"c9viqzd"
],
"score": [
4
],
"text": [
"Partially inflation and partially they just get bigger and fancier and it's kind of a competition to have the most kick ass stadium that they spend more and more money.\n\nEdit: taking a shot at the repair remark, you didn't mention what kind of repairs. You might be thinking that some seats maybe some wall stuff but what if it's something major? Think of it like a car. It might cost me a few hundred to get new tires, paint job, new seats. Nothing too serious, so cheap. Now imagine that I need to overhaul the whole engine, frame, transmission, and while I'm there I'm going to add in the cosmetic changes. And I want it done FAST. Whole different beast. That's another factor: speed. You need it done good and fast. So it won't be cheap. Every week your stadium is under construction is a week you're not making money, hell you're losing money. Better to drop that amount and have it done in the off season then let them work slow and have it run into the money-making season. \n\nSpecial equipment, safety checks, construction completion bonuses. There's so much to it that's it not hard to imagine it getting that high that quick. "
]
}
|
[] |
[
"http://prod.static.vikings.clubs.nfl.com/assets/docs/stadium/DES-recent-nfl-stadiums.pdf"
] |
[
[]
] |
|
s6mob
|
I am swimming in a pool of water on the moon. How will the lower gravity affect the way I can swim?
|
Assume I am in a 1 atm chamber so I can breathe freely and there is a large pool. Does the lower gravity change the rate at which I would float and sink in the water? Would the pressure of the water as I go down be affected such that I could dive deeper or swim up to the surface faster or more easily?
EDIT 1: I just want to clear this up. Assume I am in a pressurized, heated colony and am using the colony's olympic swimming pool (25 X 50 X 2.5 metres), so I can swim about as far or as deep as I would like to and do not need supplemental oxygen.
EDIT 2: Thanks everyone for your great input. Here are some of the best answers and points I've read.
• Buoyancy stays the same, but the effect of gravity is less strong, so I would oscillate in the water more severely up and down if I were treading water. Waves will be much higher because of this, causing a potential drowning hazard.
• [shiningPate](_URL_0_) had a good point about the ease of moving out of the water like a penguin or dolphin, but my physical buoyancy will not change, just the thrust required to exit the water.
• The thread following [madnote's comment](_URL_1_) explains that viscosity or ease of motion through the water is a major
• The pressure differences are fairly negligible due to the fact that the Moon's gravity is only about ⅙ that of Earth. At the bottom of the swimming pool at 2.5 metres, the pressure would be similar to about 0.42 m on Earth, but if I were in a much deeper pool, I could dive down more like 30 m and be affected as much as going down 5 m on earth
• Also, [condorcet_winner](_URL_2_) asks an interesting question that I would like to see answered.
|
askscience
|
http://www.reddit.com/r/askscience/comments/s6mob/i_am_swimming_in_a_pool_of_water_on_the_moon_how/
|
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"pool story, bro.",
"Hmm. Interesting question. The density difference between you and the water would be the same as on earth, but the gravity is different. You would still float but not as significantly because the different densities wouldn't be as big of an \"up and down\" gravity difference. You weigh less, but so does the water.\n\nTo answer questions like this sometimes I like to think of the extremes. Gravity is less on the moon so what if we think of the extreme and think of a pool in space where there is no gravity. Water is floating all over and you don't \"float\" anywhere. If we start adding gravity to one side the water and you body slowly get pulled to that side but you can easily still swim around without worrying about floating to the top right away.\n\nAlso, pressure is force(weight) over area. With 10 feet of water you have less weight so the pressure is less.\n\nI would say it would be easier to swim around and you could also go deeper, as you could withstand the pressure at greater depths. BUT, should you be 30 feet down you would not shoot to the top as easily if you pushed off the bottom because you don't float as well.\n",
"I want to hear more detail. The smaller forces would mean if you dip below your point of neutral buoyancy it would take longer for you to rise back up. And similarly if you gave a particularly powerful stroke while treading water and rose above the surface some you would sink back down much slower. So I can only imagine that swimming would be very awkward. The same movements we do in 1G would now raise our body much farther out of the water right?\n\nWould we feel less resistance when pulling our hand through the water? Would we be able to swim faster? Would the surface of the water be much more turbulent, I mean would waves travel farther across the surface of the pool and last longer? ",
"He said \"swimming\", not \"floating\".. \n\nI think that a major effect you will notice is in the waves that you will produce while swimming, they will probably be higher and slower. Another effect, minor, is that you will experience less resistance to breathing because the net force of water pressure on your torax is lower.",
"If there were liquid oceans on the moon would the tides be massive? ",
"Related question: because of the decreased gravity, but same buoyancy would it be possible to run on water (and let's just say for the sake of argument that you have flippers that double/triple your surface contact)?",
"When you're in the water, gravity is basically replaced by an effective gravity based on the ratio of your density of that of the water you displace, so you basically simply weigh much less if your density is greater than that of water, a negative amount if your density is less, and you're completely weightless if your density is equal to that of the water. An air mattress pool toy has much lower density than the water itself, so it has essentially negative weight: it falls *up* to the surface. The human body is more dense than water, but not by that much, so we just have a lower weight than when we're in air. Much more dense objects like lead weights are barely affected by the presence of water at all.\n\nSince the gravity itself is replaced by an effective gravity, this reflects a change in the gravitational acceleration. In a vacuum, heavy things and light things fall at the same rate. In a fluid such as water or air, buoyant forces will cause denser objects to fall more quickly and less dense objects to fall more slowly -- or upwards if they are less dense than the medium, like a helium balloon in the nitrogen atmosphere. A change in gravity means not just that you weigh less but that you fall slower.\n\nHowever, water is a VERY viscous fluid compared to air, so our movement is slowed significantly by water resistance. We don't notice air resistance so much in our normal movements, but water resistance is so large that we can easily fight gravity and swim. We can't do that in the air! Birds can, though. Well, we technically *could* do that in the air, if we had a LOT more power output in our arms. Anyway, point is, water is no different from air except that it's much heavier and much thicker (more viscous), so that not only is the change in effective gravitational acceleration *noticeable* but also our meek human strength is enough to make it *controllable*.\n\nSo what would happen if we replaced the basic gravitational acceleration? It would just scale everything. You'd fall at a different speed. If it's the same water, though, it's going to have the same viscosity, so at smaller gravities, decreased falling speed will mean your human muscles will have to do a lot less work to keep you from sinking.\n\nBy the way, since the effective gravity is just based on the ratio of densities, you could easily simulate being in a pool on the moon or on Jupiter by changing your density! Preferably you'd do it in a consistent way. You could wear air-filled bracelets and anklets, for example, and maybe something air-filled around your waist; that would decrease your average density. You could do the same with lead and increase your average density. Other than the fact that the density won't be evenly distributed, this would be indistinguishable from actually changing the gravity.\n\nSo long as you stay underwater (it won't help in the air), don't cause any waves (those are driven by gravity), etc.!",
"The rate of pressure change with depth is dependent of the local gravity, and will be much smaller - one additional atmosphere per 60ish meters.\n\nYou would be in danger of water inhalation, of course, because any splashes you make would be much bigger and stay in the air longer.\n\nIf you have a rate at which you float/sink, then this will be changed. The upthrust will be exactly equal to the weight of water displaced by your body, and the weight changes on the moon.",
"Your buoyancy would remain the same. However, because gravity wouldn't be as strong you could jump through hoops like a dolphin. Don't set the hoops on fire, though. Remember, you've got limited air.",
"When you're under water, the upward for of buoyancy of the water is neutralizing the downward pull of gravity. This is why the astronauts train for spacewalks in large water tanks. However with swimming, at least with some strokes, you are partially operating in water, partially with your body out in the air, and those body parts are subject to gravity. \nAs a competitive swimmer, you really feel the gravity pulling down your arms swimming freestyle as you lift them clear of the water to bring them forward (especially after a long race)\nButterfly would seem to be the most affected by lower gravity. With butterfly, you time your kick to thrust your body up out of the water just at the moment when you want to bring your arms forward to return them to the beginning position for the stroke. Great butterfly swimmers are able to bring their entire upper torso clear of the water for the return stroke. Gravity resists this manuever. Assuming you could achieve equivalent thrust in the water (as many here have stated), at1/6 gravity, you should be able to achieve a greater loft out of the water. \nPerhaps you might even be able to clear your entire body clear of the water and arcing forward like swimming penguins: _URL_0_",
"Any waves you produce will be bigger and slower than they would be on Earth."
]
}
|
[] |
[
"http://www.reddit.com/r/askscience/comments/s6mob/i_am_swimming_in_a_pool_of_water_on_the_moon_how/c4bsu0q",
"http://www.reddit.com/r/askscience/comments/s6mob/i_am_swimming_in_a_pool_of_water_on_the_moon_how/c4bjs7h",
"http://www.reddit.com/r/askscience/comments/s6mob/i_am_swimming_in_a_pool_of_water_on_the_moon_how/c4bp3vh"
] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[],
[
"http://www.arkive.org/macaroni-penguin/eudyptes-chrysolophus/video-06a.html"
],
[]
] |
|
5l90ql
|
Any WWII historians out there, can you identify this medal? It was given to a civilian who worked in an evasion line in Belgium that helped Allied airmen escape the occupying German forces.
|
_URL_0_
Granted, this is from a 1970s TV series called "Secret Army" but it is apparently based off of real events. Is this a real medal, and if so, can you tell me what it is? It may be Belgian or British, as the man holding it was Belgian working for London.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/5l90ql/any_wwii_historians_out_there_can_you_identify/
|
{
"a_id": [
"dbtxjwm"
],
"score": [
3
],
"text": [
"That's the Belgian War Cross. It was given to soldiers and civilians for showing bravery in actions against the enemy.\n\nOn second sight: some things are off. The cross is not exactly the same (_URL_0_) and the middle figure should be a rampant lion or the Kings sigil (two stylised L's with a roman numeral 3). So it's likely a prop based on the War Cross."
]
}
|
[] |
[
"http://imgur.com/BDmT5Qy"
] |
[
[
"http://imgur.com/a/bx1om"
]
] |
|
sk2a9
|
why does good food taste bad and bad food taste good? (bonus for asking it like a 5 year old?)
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/sk2a9/eli5_why_does_good_food_taste_bad_and_bad_food/
|
{
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"text": [
"Because our brains evolved during times when there was less food.\n\nNow we use hi-tech methods to make a truck-load of anything we want to eat.\n\nSo the same mechanisms that make us want to eat more of less available stuff, makes us eat more of abundantly available substances.\n\nMore of any food is bad. Therefore good food tastes bad, and bad food tastes good.",
"Food with lots of energy that are easy to digest (carbohydrates like table sugar, and fat) were the best food sources when food is scarce. Animals evolved to like these food sources: animals that thought these foods tasted good ate more of it, had more energy to outlive famine and able to produce more babies, thus they outnumbered and eventually became to be the majority of animals.\n\nOnce humans invented agriculture and especially after the industrial revolution when it became cheap and easy to make food, it is easy to find sugary, fatty foods. Evolution took a long time, so it is hard to change what we naturally like over decades or centuries.\n\nAlso, your preference for foods depends on your upbringing; some people really like certain foods because they grew up eating it. If your family ate lots of vegetables, you probably like vegetables more than the average person."
]
}
|
[] |
[] |
[
[],
[]
] |
||
54yt7e
|
why do all trucks' wheel assemblies stick out on front tires, but don't on rear tires?
|
Whether you are talking about [dump trucks](_URL_3_), [18-wheelers](_URL_2_), [box trucks](_URL_1_), or [other work trucks](_URL_0_), it seems that all of them have wheel hub assemblies that stick out from the tire in the front and don't in the back.
Why is there this difference?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/54yt7e/eli5why_do_all_trucks_wheel_assemblies_stick_out/
|
{
"a_id": [
"d863fze"
],
"score": [
3
],
"text": [
"It's so they can use the same size lugs on the front and back.\n\nThe ones on the back need to be long enough to accommodate two sets of wheels. The front only has one set, so they stick out "
]
}
|
[] |
[
"http://www.mheby.com/wp-content/uploads/2013/03/grain-truck.png",
"https://upload.wikimedia.org/wikipedia/commons/6/62/Isuzu_box_truck.jpg",
"http://www.18wheelertruckandtrailer.com/siteart/truck1.jpg",
"http://st.motortrend.com/uploads/sites/5/2012/04/2012-Ford-F-650-Dump-Truck-rear-view-up.jpg"
] |
[
[]
] |
|
3anldo
|
If the sun converts hydrogen to helium where does it get the neutrons to do so?
|
I'm a pretty sciency guy but my 12 year old daughter has stumped me with a few question.
If the sun starts out as a dense ball of hydrogen (one proton and one electron) and uses nuclear fusion to convert it into helium (2 protons, 2 neutrons, 2 electrons), where does it get the neutrons?
Also if the atoms in the sun are a plasma (stripped of their electrons) where do the electrons go? Does that mean the sun is a giant positively charged object if it has no electrons?
Daddy doesn't know everything.
|
askscience
|
http://www.reddit.com/r/askscience/comments/3anldo/if_the_sun_converts_hydrogen_to_helium_where_does/
|
{
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"text": [
"The initial protons come about from proton-proton collisions. Usually the two bound protons decay by falling apart, but rarely through the weak force, beta+ decay occurs converting one proton into a neutron. You can see this outlined here: \n_URL_0_ \n\nThis gives you deuterium, next helium-3 and lastly helium-4 is formed. \n\nWhen plasma is formed, the electrons don't disappear, they remain in the plasma with the free protons. While astrophysics processes might bleed more or less electrons in say solar wind, hopefully a solar physicist shows up to clarify. I believe solar wind is charge neutral and so is the Sun and the magnetic fields are generated from convection. ",
"Two atoms of hydrogen are combined to create helium-4 and energy in several steps:\n\n1. Two protons combine to form a deuterium atom (hydrogen atom with one neutron and one proton), a positron (similar to electron, but with a positive charge) and a neutrino.\n2. A proton and a deuterium atom combine to form a helium-3 atom (two protons with one neutron) and a gamma ray.\n3. Two helium-3 atoms combine to form a helium-4 atom (two protons and two neutrons) and two protons.\n\nThese reactions account for 85 percent of the sun's energy. The remaining 15 percent comes from the following reactions:\n\n1. A helium-3 atom and a helium-4 atom combine to form a beryllium-7 (four protons and three neutrons) and a gamma ray.\n2. A beryllium-7 atom captures an electron to become lithium-7 atom (three protons and four neutrons) and a neutrino.\n3. The lithium-7 combines with a proton to form two helium-4 atoms.",
"Here's a simple explanation:\n\n > > If the sun starts out as a dense ball of hydrogen (one proton and one electron) and uses nuclear fusion to convert it into helium (2 protons, 2 neutrons, 2 electrons), where does it get the neutrons?\n\nNeutrons appear when two protons fuse to form deuterium:\n\nproton + proton = > deuteron + positron + neutrino\n\nDeuterium nucleus (deuteron) contains a proton and a neutron. You could simplistically think about the formation of a neutron as a proton capturing an electron, or more precisely as a proton splitting off a positron.\n\n > > Also if the atoms in the sun are a plasma (stripped of their electrons) where do the electrons go? Does that mean the sun is a giant positively charged object if it has no electrons?\n\nNo no, you got it all wrong! When they say that electrons are stripped off the nuclei, they just mean that they aren't bound to a particular nucleus like they would be in a neutral atom. But the electrons stay in the same plasma as the nuclei, so the plasma is always electrically neutral. Plasma is a mixture of electrons and partially (or fully) ionized atoms from which they were \"stripped\"."
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Proton–proton_chain_reaction"
],
[],
[]
] |
|
2cvu1j
|
why do i keep hearing that obama doesn't follow the constitution? what exactly is he doing that is unconstitutional?
|
UPDATE: I now get the basic premise. Thank you, everyone. However, this has also confused me as to how many politics in America work (or don't in some cases). I'm so glad I have marketable talents and education in other areas, 'cause I'd never make it in politics.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2cvu1j/eli5_why_do_i_keep_hearing_that_obama_doesnt/
|
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"He has used a device known as the \"executive order\" to create policy and law without congressional approval. According to the Constitution, Congress drafts and votes on laws with the President having power to veto or sign the bill into law. Executive order has been used at times by many Presidents but it is never mentioned in the Constitution.\n\nObama is not unique in using the executive order to quickly enact law or circumvent an unwilling Congress. Throughout the 20th century and up to now, the role of the President has been constantly expanding. The President does *far* more now than he ever did historically.\n\nI think the lawsuit is interesting because it challenges the limits of executive orders and the expanding role of the President outside the Constitutionally granted powers. That said, there's so much posturing, gimmicks and gamesmanship from both political parties that this is little more than a stunt leading up to the November midterm elections.",
"You keep hearing about it because it's an inflammatory type of thing that gets voters outraged, in a climate where most people get their news from sources that rely on inflammatory content for ratings.\n\nObama has issued a number of executive orders, and the argument is that some of these executive orders violate the Constitutionally-mandated balance of powers between the legislative and executive branch. \n\nWhether this is true or not is very murky indeed, in part because executive orders themselves do not have very clearly delineated boundaries.",
"I wouldn't say that it's necessarily unique to Obama, but a couple examples I can think of off the top of my head:\n\n* Continuation of domestic spying programs violates the 4th amendment. It's the NSA/Snowden scandal. Basically, any individual is supposed to have a warrant against them in order to have their phone records, emails, etc. searched, but instead the government has been doing it in mass without warrants.\n\n* Drone striking American citizens, in violation of the 6th amendment. Obama ordered drone strikes to assassinate a couple of terror suspects, including a teenager, in Yemen, who were all American citizens. According to the 6th amendment, they were entitled to a trial, which they were not given. Oddly enough, I've found that conservatives I know who criticize Obama are largely okay with this.\n\n* People are always screaming about how Obama is going to enact anti-gun legislation in violation of the second amendment, but I can't think of anything specifically that he's done on that from.",
"First of, this is a political issue that is heavily debated by Liberals and Conservatives. You're not going to get a simple answer here.\n\nThe short answer is that he hasn't. What is referenced is his use of executive action to pass legislation without congress. What this means is that he is using a power granted to him by the rest of the government to push his administrations agenda. Whether this is a good thing or a bad thing is another discussion, but the important thing is that certain Conservatives are calling this an abuse of power, and calling for impeachment.\nImpeachment is the process by which the president is tried for abuse of power and doing things that harm the country.\n\nWhat is important here is the the President is using a completely legal action, and hasn't done anything to actually harm the nation or even prove him an ineffective leader. In addition, he (183) hasn't even used this power as much as his predecessor, George Bush (291), and in fact is the third to last in amount of Executive Orders since President William McKinley in 1897. In comparison, Reagan made 381, Clinton made 364, and FDR made 3,522 (nope, not a typo).\n\nThose who say he violated the Constitution are doing so either out of being misinformed or for political reasons.\n\nTl;Dr: He hasn't, its a political maneuver by Republicans in the GOP.\n\nedit:spacing",
"Allowing and expanding 4th Amendment violations.\n\nOrdering drone strikes on American citizens, one of which was not even a \"suspected terrorist\".\n\nIndefinite detention of American citizens without trial.\n\nThe ACA which orders people to engage in commerce.\n\n",
"One argument is that he is violating the Constitutional provision that the president must \"take care that the laws be faithfully executed\" by delaying the implementation of several parts of the Obamacare legislation.\n\n\n[The Economist](_URL_0_) has a pretty good discussion of this argument and the associated lawsuit.\n\n\nI think most people would agree that the executive branch can't possibly enforce every law on everyone, simply due to limited resources. The DEA can't bust every drug smuggler, so they must concentrate on certain suspects or certain types of violations. On the other hand, if a president just arbitrarily picks and chooses what laws to enforce based his opinions on policy (\"I don't agree with this law, so I won't enforce it\") or politics (\"enforcing this law now would be bad for my administration and/or my party, so I won't\"), is he failing to take care that the laws be faithfully executed?",
"As Jon Stewart pointed out. If you're choosing to NOT impeach someone because of how it may affect your upcoming mid-term elections, that person is, by definition, NOT a tyrant (or doing anything unconstitutional).\n\n_URL_0_",
"[Here](_URL_0_) is the list of Executive Orders that Obama has issued.\n\n[Here](_URL_1_) is George W. Bush list of Executive Orders.\n\nTake a look at the differences (there are not much btw). But like others have stated, most Executive Orders are issued to agencies that are under the power of the US President where congress gave regulatory leeway.\n\nIn the ACA there were no \"Regulatory Leeway's\" put into the implementation dates.\nCongress put forth a second law (after the Republicans took power) to delay the whole act. This was vetoed by the President. Who then went on to implement portions of it via the \"Executive Order\".\n\nThe US Constitution only gives the President power over Regulatory Branches and veto power of the law passed by congress. He is not given the power of Line Item Veto (after the fact).\n\nTo look at it deeper, President Obama delayed a Tax Law (only congress has that power) as stated by the SCOTUS. This is the highly unconstitutional thing that he has done. The House of Representative is the only branch that has the \"Power to Tax\".\n\n > Several Constitutional provisions address the taxation and spending authority of Congress. These include both requirements for the apportionment of direct taxes and the uniformity of indirect taxes, the origination of revenue bills within the House of Representatives, the disallowal of taxes on exports, the General Welfare requirement, the limitation on the release of funds from the treasury except as provided by law, and the apportionment exemption of the Sixteenth Amendment.\n\nEssentially, when President Obama delayed the Tax Penalty (Mandate on Business or pay a Tax) he usurped the power given to the House of Representatives. Our whole society is based on checks and balances. If President Obama's action becomes precedent, who is to stop the next Republican President to sign an Executive Order stating that all Taxes on Business and High Income Earners shall not be levied, or shall only be levied at \"Stated Rate\".\n\nWhen you put out that scenario, both Left and Right (people for ACA or against) should be leery of any President implementing Tax Laws unilaterally. This is why it was specifically given to the Representatives of The People (House of Representatives). Not the States (Senate) and not the President.\n\n\nThe whole thing does go much deeper than that, so it would not be an ELI5."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[
"http://www.economist.com/blogs/democracyinamerica/2014/08/lawsuit-against-obama"
],
[
"http://thedailyshow.cc.com/videos/739w4w/bad-impeacher"
],
[
"http://en.wikipedia.org/wiki/List_of_United_States_federal_executive_orders_13489_and_above",
"http://en.wikipedia.org/wiki/List_of_United_States_federal_executive_orders_13198%E2%80%9313488"
]
] |
|
8h4wcm
|
why was scurvy more likely to occur at sea (vs land)?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8h4wcm/eli5_why_was_scurvy_more_likely_to_occur_at_sea/
|
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"text": [
"Scurvy was brought on by a lack of Vitamin C. And while fruits and other foods containing it were common parts of people's diets on land, such foods are difficult to preserve over a long sea voyage. ",
"Being at sea meant a lack of fresh food. On land you had easy access to fresh greens, dandelion or nettles are actually edible and very nutritious. \n\nAt sea you had stuff like canned food, salt meat, dried biscuits, etc which could be kept for long periods but lacks many vital nutrients, including vitamin C. ",
"Scurvy is caused by a deficiency of vitamin C. Humans and deer are essentially the only animals that do not naturally produce vitamin C. A diet of fresh meat and produce will generally have more than enough dietary vitamin C to avoid scurvy. The problem is that during long sea voyages, sailors did not have access to those foods. ",
"Humans and other primates have inherited a gene mutation that prevents us from synthesizing vitamin C from glucose.\n\nIn a certain sense this may be seen as a genetic disease. On land, it's rarely a problem, since many plants and fruits in particular, contain large amounts of vitamin C. The reason why many plants overproduce vitamin C isn't known. It may be to protect from UV damage or to resist fungi.\n\nMost other animals besides primates can produce vit. C as needed.\n\nHowever, vitamin C is a rather unstable compound. It has a limited shelf life of a few weeks at best, it's also destroyed by cooking. \n\nThe problem with long sea voyages is the lack of access to fresh fruits and vegetables. Sailors largely depended on dried, pickled, or salted food, and after a few weeks, all of the vitamin C tended to decompose. Fishing could provide meager amounts of Vit. C,but this is both unreliable for a large crew, and wouldn't provide enough C intake and would only delay scurvy.\n\nMany seaweeds contain C, but this also isn't reliable in the open ocean. Sailors wouldn't have known the connection between fruits/veggies and preventing scurvy. "
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
3wptpq
|
How scientific is the idea that communicating is 80% body language, 15% tone and 5% actual words (or whatever the numbers may be, I've seen them a couple of different ways)?
|
I've heard this a few times and it always bugged me that the words I choose to use may be ignored because I'm standing funny or something. I wonder if people use this idea as a crutch or something like that.
|
askscience
|
https://www.reddit.com/r/askscience/comments/3wptpq/how_scientific_is_the_idea_that_communicating_is/
|
{
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"text": [
"First of all, I have no real knowledge on the matter, but since you havn't gotten an answer, ill give you my thinking.\n\nTo me its completely nonsense, as you can easily think of a case of 100% body language (sign language) and 0% body language (two blind people talking)\nBy that logic you can find everything between, lets say, talking to Stephen Hawking, almost no body language and no tonation. Neil Degrasse Tyson on the other hand :)\n_URL_0_\n\nSo giving a percentage is to me very wrong as it is very individual and situational."
]
}
|
[] |
[] |
[
[
"http://www.reactiongifs.us/wp-content/uploads/2013/03/i_dont_even_ndt.gif"
]
] |
|
ea2e4v
|
Why did the flintlock pistol/bayonet combo replace pikes and matchlocks?
|
What benefits were there to the former that made such a massive transition worthwhile?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/ea2e4v/why_did_the_flintlock_pistolbayonet_combo_replace/
|
{
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"text": [
"Soldiers armed with flintlock muskets and bayonets were what replaced infantry armed with matchlocks and pikemen. The short answer would be, of course, that they replaced them because troops with them tended to win the battles.\n\nThe advantages of muskets and bayonets was pretty obvious: Before, there was one soldier with a long-distance weapon ( matchlock) and another soldier with close-in weapon ( pike). . There were limitations with pikes. They were pretty good in simple defensive positions against cavalry, but in a block of pikemen only the front ranks did most of the effective work. To maximize their distance effect ( beyond sword range) pikes also tended to be too long for very close combat ( often around 16 feet) and two blocks of opposing pikemen could get pretty tangled up and so become bogged down. A musket with a bayonet replaced two soldiers: it gave one soldier both a long-distance weapon ( musket) and a close-in weapon( bayonet).\n\nMatchlocks required care. Each soldier had a tin tube dangling from his waist to carry some match. That either slowly burned, or it had to be lit. Naturally, if the soldier was to be ready, the match had to be lit- and kept lit. That lit match was also never far away from the loose gunpowder the soldier would be using to load his gun, especially in priming the pan,and care had to be taken that there wasn't a slip and an accidental firing. The string of cartridges often seen hanging from bandoliers, in the late 16th c and earlier 17th c., could go off , leaving a very unhappy soldier. There was also the problem of weather. Black powder is hygroscopic, and if at all damp will not work. Muzzle-loaders of all kinds have problems with rain and humidity, but a flintlock can be at least partially shielded - grease put under the steel to seal the pan, the gun carried with the lock in the armpit. Not possible with lit match.\n\nHowever the advantages, the change would happen pretty slowly. Matchlocks are simpler, and so, cheaper. Though the French would introduce the first practical flintlocks in the 1630's, and they would become more and more popular during the 30 Years War, matchlock muskets and pikemen would still be around into the 1690's, and even later. But pikemen by then would have been much fewer, and would long have been taken out of their blocks and mixed with soldiers with muskets",
"I assume you mean the rifle, and not the pistol\n\n & #x200B;\n\nThe answer is a development in tactics and firearms technology. Arquebuses used during the age of pike & shot were heavier, slower to reload, and would often be placed in y-shaped holders to steady it during firing. This, and their comparatively shorter length to muskets, made gunners vunerable to cavalry charges. Thus, they were protected by pikemen who could repel cavalry charges but were themselves vunerable to arquebuses. \n\nWhen the longer and faster to reload muskets were introduced, more and more arquebuses were already being added to infantry formations as the advantages of superior firepower on the battlefield were greater than more meele fighters. The Swedes under Gustavus Aldolphus removed the halberd fromt their formations and made the infantry entirely equipped with pikes and guns. \n\nA musket has a superior rate of fire to an arquebus, and increased firepower leaves the musket as the superior weapon of choice instead of pikes for every soldier. Second, a musket with a bayonet is essentially a spear, giving every man a polearm to fend off cavalry. Suddenly your entire formation can both shoot, fend off cavalry, and fight in meele if needed.\n\n & #x200B;\n\n1. In a shooting match between a pike & shot formation, a similarly sized unit only equipped with muskets will outgun their enemy\n2. If the enemy pushes with pikes, they suffer high casualties on the attack with no means of retaliation\n3. If the enemy is all meele, your troops can both shoot and stand and fight\n4. If the enemy is all guns, bayonets gives the advantage to close and fight in close quarters while still outgunning the arquebus\n5. With bayonets, disciplined infantry can ward off cavalry attacks\n\nSo the superior firepower and increased flexibility of a musket with a bayonet will outperform arquebus and pike nearly every time."
]
}
|
[] |
[] |
[
[],
[]
] |
|
6yvjug
|
how do motorcycles differ when they have the same kw (hp) but different ccm?
|
I am looking to do my motorcycle license, and will be allowed to drive a bike up to 35 Kw (48ps). But there are some bikes with 300ccm and some up to 700ccm, but they all have 35 Kw. What is the difference and what will I notice? (e.g. sound, acceleration, mileage, etc..) I am completely clueless.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6yvjug/eli5_how_do_motorcycles_differ_when_they_have_the/
|
{
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"text": [
"The smaller engine will rev higher to produce the same power as the larger one. Acceleration will be better on the larger engine because it produces more torque, which is the force that gets you moving (this is a generalized statement as gearing would affect this.) It will also work less hard, potentially saving wear and tear. Fuel efficiency will most likely be better on the smaller engine. The larger engine will probably produce a throaty sound compared to the higher pitch smaller engine which is running at a higher RPM. "
]
}
|
[] |
[] |
[
[]
] |
|
2klpb6
|
What factors come into play with the abundance of elements in the universe?
|
Hydrogen and Helium are the most and the second most abundant elements in the universe respectively, but Oxygen is third. My understanding is that most of the elements heavier than [H] and [He] are created through astronomical events such as the goings on within a star.
Why is Oxygen not the 8th most abundant element? What factors come into play, with Oxygen and all of the other known elements?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2klpb6/what_factors_come_into_play_with_the_abundance_of/
|
{
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"clmzc19"
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2
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"text": [
"Theoretically, helium and hydrogen were the first to form and formed the most because of their simple structure. This was just caused by quarks combining slowly after billions of years. Nuclear fusion breaks down this process and with the death of a star comes the highly compact neutron star containing the higher density elements. To put it in perspective, a sand speck of a neutron star is so dense that on earth, it weighs more than the Empire State Building. Eventually, neutron stars collapse under their own gravity & we get elements & planets & everything else."
]
}
|
[] |
[] |
[
[]
] |
|
m5nxj
|
how do you play "street" craps?
|
Not sure if it's different from casino craps.
I'm watching a Bronx Tale where Sonny has C throw. I was wondering how the rules go. I've always wanted to know. Looked up once and it didn't make much sense in the article. Maybe a Redditor could dumb it down.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/m5nxj/eli5_how_do_you_play_street_craps/
|
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"text": [
"The most common form of street craps is [Cee-lo](_URL_0_). There are many variations of the rules, but according to Wikipedia, the base rules are as follows:\n\n\"*The constants include the number of dice used, which is always three. All rules describe certain winning combinations that can be rolled, and 4-5-6 is always treated as a winning combination for the first player who rolls it (though in some variants without a banker, it may be possible for several players to make a \"winning combination,\" requiring a second shootout). Besides the winning combinations, all Cee-lo rules include certain rolls that establish a \"point,\" and there are situations where two or more players will roll and compare their points to determine a winner. If for any reason the dice were to leave the playing area (ex: rolling off of the table and hitting the floor) the player would be deemed an automatic loss.*\"",
"The most common form of street craps is [Cee-lo](_URL_0_). There are many variations of the rules, but according to Wikipedia, the base rules are as follows:\n\n\"*The constants include the number of dice used, which is always three. All rules describe certain winning combinations that can be rolled, and 4-5-6 is always treated as a winning combination for the first player who rolls it (though in some variants without a banker, it may be possible for several players to make a \"winning combination,\" requiring a second shootout). Besides the winning combinations, all Cee-lo rules include certain rolls that establish a \"point,\" and there are situations where two or more players will roll and compare their points to determine a winner. If for any reason the dice were to leave the playing area (ex: rolling off of the table and hitting the floor) the player would be deemed an automatic loss.*\""
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Cee-lo"
],
[
"http://en.wikipedia.org/wiki/Cee-lo"
]
] |
|
1rwm6e
|
why is it meaningless to say if it is 20 degrees oc, that it is twice as hot as if it was 10 degrees oc?
|
I understand the variable is not ratio, as it's absolute 0 (0oC is not the lowest possible temperature) but I don't understand the answer to my question.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1rwm6e/eli5_why_is_it_meaningless_to_say_if_it_is_20/
|
{
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"text": [
"Convert Celsius to any other temperature measurement unit and you'll see why it is meaningless. \n \n10 degrees Celsius = 50 degrees Fahrenheit \n20 degrees Celsius = 68 degrees Fahrenheit \n \nI hope it makes it a bit clearer to you now.",
"First thing's first - Temperature\n\nThe temperature of matter, is a numerical measure of heat, which itself is an approximation of the internal energy of the matter.. That is to say, high temperature matter matter has more energy than low temperature matter. \n\nSo Celsius... The original Celsius scale (a.k.a centigrade) was defined by the environment we find ourselves in... Define that 0°C is the point that water freezes (a common thing we can relate to), define 100°C as the point where that water boils (another fairly common temperature point), and then arbitrarily divide up the range between those two points into 100 equal divisions (**Centi**grade).\n\nCelsius is a useful scale for every day life, as almost all of the temperatures we encounter will be a nice sensible value somewhere between 0°C and 100°C..\n\nBut as others have explained, when comparing actual energy levels the Celsius scale is useless, since it doesn't relate to *any* fundamental standard (such as absolute zero). \n\nInstead you must compare an absolute temperature (Kelvin or Rankine), which are defined as having their 0 points as absolute zero.."
]
}
|
[] |
[] |
[
[],
[]
] |
|
15n3tm
|
What really happened in North America immediately before Columbus arrived?
|
So, according to [some guy in Ask Reddit](_URL_0_) (always a great place to find reliable sources) a plague wiped out "98%" of Native Americans before Columbus arrived. I find this really difficult to believe and can't even begin to wrap my mind around that level of cataclysm. The Black Death only killed 1/3 of Europeans and that was an enormous catastrophe. This sounds like either a gross exaggeration or revisionist history to me. However, I know the current theory is that there was some sort of major disaster, so I have a few questions:
1. What is generally believed to have happened?
2. If there was some sort of major plague or ecological disaster, why haven't we found mass graves from the period?
3. What rule did superior European technology actually play in the conquest of North America?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/15n3tm/what_really_happened_in_north_america_immediately/
|
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"text": [
"Many Native Americans were killed by diseases brought to the continent by the Europeans. And, because diseases spread faster than colonists, many tribes were wiped out before the Europeans actually found them. I won't comment on the actual statistics, but these new diseases did kill *a lot* of Native Americans.\n\nThere's a lot more information in [these previous questions on this topic](_URL_0_), on our Popular Questions page.\n",
"Columbus didn't arrive in [North America](_URL_0_).\n\nConsequently (*after*, not before!), different diseases, coupled with overworking, and incredibly bad living conditions killed a huge majority of the Carribean Islanders, and many indigenous people on the mainland. See [Bartolome de Las Casas](_URL_1_).",
"The introduction of bubonic plague into Europe can't really be compared to the introduction of smallpox -- and every other Eurasian/African disease -- into the Americas. Europeans were not an entirely *Y. pestis* naive population. The Plague of Justinian, for example, is thought to have been the result of *Y. pestis*. The simple fact is that bubonic plague was endemic in Eurasia and therefore comparing the experience of a Eurasian population to a particularly virulent strain of an already present disease to a completely disease-naive population is comparing apples to avocados. \n\nRemember, the Siberian populations that peopled the Americas did so before the onset of many of the communicable diseases we now take for granted as part of historical life. Even arboviruses like malaria and yellow fever, which can directly infect, or have analogues in, other primates, were unknown due to the climatic region that the Americas were peopled from. So it makes biological, and simply logical, sense that these groups would have a response to infectious diseases unprecedented in Eurasian groups.\n\nThis wasn't a unique occurrence in the Americas. In addition to the accounts from Americas during contact, we also have corroborating evidence from the Pacific Islands and Australia which also showed similar (~90% or more) mortality rates from introduced disease, sometimes without any further European intervention. Similarly, new modern diseases also have staggeringly high mortality rates. Ebola, even with treatment, can have mortality rates of 70% or more. AIDS, without treatment, has a long-term mortality rate of almost 100% (barring a few genetic mutations). This is an established pattern for newly introduced diseases, not revisionism or exaggeration.\n\nOn to your specific questions:\n\n**(1)** Major epidemics of infectious diseases led to massive population collapse, often ahead of direct European contact via indigenous economic/social contacts. The demographic collapse was compounded by war, enslavement, and general debasement and devaluation of Americans' lives by colonial powers. Stannard's book, [*American Holocausts*](_URL_1_), while controversial, is the book to read on this subject; draws heavily on the already mentioned de las Casas.\n\n**(2)** You're making an ethnocentric assumption that every culture buries their dead. Cremation, for example, was a common practice in Mesoamerica, and other American cultures also burned their dead. Others, however, did bury their dead, and many grave sites, and even mass burials have been found. Skeletal remains, though, are generally terrible at showing evidence of infectious disease (aside from a few prominent infections that induce osteological changes). Particularly in the American Southeast, there is a robust debate over whether burials represent mass mortality from infectious diseases or from other factors like forced labor, violence, starvation, etc.; King Site in Georgia and Tatham Mound in Florida are two such cases. [Here's a paper discussing the archaeological evidence](_URL_0_) of die-offs from diseases peri-Contact.\n\nAlso, keep in mind that there have to be people around to bury the dead in order for there to be mass graves, and that bodies exposed to the elements and scavengers do not have the best preservation rates. Accounts from early settlers in New England are filled with native settlements deserted as a result of disease outbreak. Even the Black Death is filled with stories of villages so affected that there was no one left to bury the dead.\n\n**(3)** Surprisingly little. In Mesoamerica the Spanish won because they exploited widespread hatred of the Mexica to lead a mass uprising against them. Gunpowder was much more scarce than has been assumed, the Spanish troops steel armor was vulnerable to Mexica weapons (many of the Spanish actually adopted native quilted armor due to the climate), and native tactics were quickly adjusted to account for introduction of cavalry. The Spanish won via disease outbreak in the astoundingly dense Tenochtitlan, mass insurrection, and a few other factors that I won't get into here for sake of brevity. Technological achievement as the cause is a sloppy post-Conquest rationalization. Similarly in the Andes, the Spanish exploited political and ethnic dissension, compounded by epidemic disease, to seize control. Throughout North America and the rest of South America, diseases raced head to depopulate the land, leaving behind socially traumatized groups of survivors. In none of these cases was European technology the decisive factor."
]
}
|
[] |
[
"http://www.reddit.com/r/AskReddit/comments/15m56c/historianshistory_buffs_of_reddit_what_are_some/c7nplkp"
] |
[
[
"http://www.reddit.com/r/AskHistorians/wiki/nativeamerican#toc_3"
],
[
"http://www.allmystery.de/dateien/gw67147,1288250002,013-Kolumbus-Columbus-Colombo-routen.jpg",
"http://en.wikipedia.org/wiki/Bartolom%C3%A9_de_las_Casas#A_Short_Account_of_the_Destruction_of_the_Indies"
],
[
"http://ge.tt/217kqQU/v/0",
"http://www.thirdworldtraveler.com/History/American_Holocaust.html"
]
] |
|
38qu46
|
what's going on with /r/thebutton
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/38qu46/eli5_whats_going_on_with_rthebutton/
|
{
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"text": [
"It hit 0 without anyone pushing the button. It's over, the subreddit is now closed (archived).\n\nThis time, for real. No server crashes, it's really, really over."
]
}
|
[] |
[] |
[
[]
] |
||
1mzkap
|
how long does it take muscle to form after exercise?
|
After strenuous exercise and assuming proper nutrition how long does it take for muscle to form or grow?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1mzkap/eli5_how_long_does_it_take_muscle_to_form_after/
|
{
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"cce201b",
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"score": [
4,
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"text": [
"This is one of the better questions on this sub in the past month or so. I'm also curious about this.",
"When you lift weights, microscopic \"tears\" form in the fascia of your muscle tissue. This is why you are sore the next day. The way muscles grow is through \"muscle recovery\": the tears fill up with new muscle cells, and the muscle is larger as a result. Think of it like scar tissue.\n\nSo the answer would then be that muscles begin growing as soon as you step out of the gym, and certainly by the time your next-day-soreness goes away. \n\nIt is a different question altogether (and likely unanswerable) about how long it takes before muscle growth can be visually perceived from one workout to the next. If I have been slacking on weightlifting for a long time and then get back into it, I typically think that I look bigger again within 3 weeks or so of starting a lifting regimen.",
"I have a follow up question: \nHow fast do muscles start to form back after you quit exercising? \nOr to put it in other words: How long can you go without exercising before you start to lose the gained muscle mass"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
n2i42
|
Why aren't we mining asteroids?
|
I understand the obscene costs involved, but the amount of materials in even just a few decent sized space rocks could rake in huge profits, as well as supply the planet with enough material to sustain itself for centuries (and thats being pessimistic).
|
askscience
|
http://www.reddit.com/r/askscience/comments/n2i42/why_arent_we_mining_asteroids/
|
{
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"text": [
"The costs are still way more than the profits. Plus there's a serious risk involved, so getting investors to fund an asteroid mining mission would be tricky anyway, since there's a good chance you'd get no profit at all.",
"People tend to severely overestimate our progress in space exploration. We have never been to another planet. While we have sent probes to Mars, they have been very basic in function and very small in size. We have only, very briefly, visited our own Moon.\n\nThe enterprise that you are suggesting is far beyond our current abilities.",
"Because it's ridiculously expensive and technologically difficult (the best we've done is bring back some dust samples) and they're largely made of the same thing that the Earth is.",
"The costs are still way more than the profits. Plus there's a serious risk involved, so getting investors to fund an asteroid mining mission would be tricky anyway, since there's a good chance you'd get no profit at all.",
"People tend to severely overestimate our progress in space exploration. We have never been to another planet. While we have sent probes to Mars, they have been very basic in function and very small in size. We have only, very briefly, visited our own Moon.\n\nThe enterprise that you are suggesting is far beyond our current abilities.",
"Because it's ridiculously expensive and technologically difficult (the best we've done is bring back some dust samples) and they're largely made of the same thing that the Earth is."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[]
] |
|
2d7yqy
|
why are there riots in ferguson, missouri? is this only because of the teen shot dead by police or are there any other causes?
|
A lot of people are talking about this on Twitter, but I am unable to find much information besides a teen that was shot dead.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2d7yqy/eli5_why_are_there_riots_in_ferguson_missouri_is/
|
{
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"text": [
"Here's the live stream if you're interested: _URL_0_",
"There was a peaceful vigil for the teenager who was shot. Somehow the vigil got violent and a riot broke out.\n\nThe rioters were *not* upset about the teenager who was shot. They saw an opportunity to raise hell throughout the area, and they took it.\n\nTeenagers robbed a gas station of beer & candy and then burned it to the ground. People have been posting pictures of their loot all over Twitter and Craigslist. No one gave a fuck about the teen; they were simply exploiting a sad situation.",
"***There's a riot on the streets. Tell where were you? ...Oh, you were home... because you're white...***"
]
}
|
[] |
[] |
[
[
"http://www.reddit.com/live/tdrph3y49ftn/"
],
[],
[]
] |
|
4g44db
|
Where did Michelangelo and the old Greek and Roman sculptors get their models? Did your average Joe look like a bodybuilder 500-2000 years ago?
|
These sculptures are totally jacked by modern standards, and a modern bodybuilder would have to very deliberately lift weights and pay close attention to nutrition. Even the "strongmen" from 100 years ago don't look nearly as impressive.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4g44db/where_did_michelangelo_and_the_old_greek_and/
|
{
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"d2egml7"
],
"score": [
6
],
"text": [
"No. These were idealized concepts of male beauty and strength. So while the statues themselves are impressive (and IMHO beautiful), they are not meant to be physical representations. For example, the pose of the Riace Bronze men. These two bronze cast statues were made by the artist to amplify every naturally occurring muscle. The training regimen to achieve this would require precise isolation workouts of muscle groups over years of training. When studied closely, recent research has also shown that the pose these two hold is impossible for a man to hold in real life - the wight balance required to portray the men as both moving and still simultaneously is not a realistic position for a human to hold. As if to further emphasize this point, the statues themselves have to buttressed with support to stand upright. These statues portray an ideal of beauty, one that is far from realistic. "
]
}
|
[] |
[] |
[
[]
] |
|
27yn5k
|
the difference in gravity between a star, and that same star becoming a black hole.
|
So, what I learned was that gravity is determined by mass, not density. Sometimes you meet the occasional clever guy that counters this by saying "but light can't escape black hole, and that's because all the matter collapsed in on the star, making much more dense, therefore having a greater gravitational pull".
I proceed to say that some of that is true, and some of it is not. From what I have gathered, if you take an example where as the sun suddenly became a black hole, no super nova, no forces, it just transformed (yes, I know it can't, but for the sake of the example it did), all orbiting bodies would stay as they where, in the same orbit as if nothing had happened. That is true because the it holds exactly the same mass as before, therefore the same gravitation. It's first when you get closer, close like the suns original surface, then the pull of gravity will be much greater because you are relatively closer to ALL the mass. Correct me if I'm wrong.
This is at least what I have learned, but my explanation doesn't seem to hold up. So, if someone could provide me with a better, and more ELI5 explanation, it would be much appreciated. Also, I'm having a hard time finding a legit source to back this up.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/27yn5k/eli5_the_difference_in_gravity_between_a_star_and/
|
{
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"text": [
"Your explanation isn't wrong.\n\nThe problem is we tend to consider objects with a specific mass as if they have no volume and ALL their mass is at one point. If you think of a black hole and a star like this, there's no real difference between them.\n\nBut they aren't like this. A star has it's mass spread out over a huge area, a black hole has it's mass spread over an area which is hard to define, possibly it's a point, but it's certainly much much smaller than any star.\n\nSo the gravitational pull on earth from the sun would be identical even if all of the sun's mass was in a single point (and it was a black hole).\n\nBut the Earth is quite far from the sun.\n\nIf you were **at the surface** of the sun, it would still be about the same.\n\nThe difference is when you're within the volume of the sun. If you're inside of it, then the pull towards the center is less, because some of the sun is pulling you **away** from the center. But if the sun had a volume that was essentially a point, then the pull would all be in a single direction.\n\nHere's a shitty diagram which is probably useless, but might help you visualize it:\n\n\nSun's mass spread out over the sun's volume:\n\n @============= < ---x- > ====)..........\n\nThe center of the sun is the '@', you are the 'x', inside the sun is the '=', the surface is the ')', and outside is '.'.\n\nBut if the suns' mass was only at it's center like a black hole and you were the same distance from that center:\n\n @............ < ----x.................\n\nThe pull would be much stronger. So the strength of the pull from an object depends entirely on **it's mass**. But how much that impacts you also depends on your distance from that mass.",
" > From what I have gathered, if you take an example where as the sun suddenly became a black hole, ... all orbiting bodies would stay as they where, in the same orbit as if nothing had happened. That is true because the it holds exactly the same mass as before, therefore the same gravitation. It's first when you get closer, close like the suns original surface, then the pull of gravity will be much greater because you are relatively closer to ALL the mass. Correct me if I'm wrong.\n\nCorrect on all counts.\n\nThis stems from something called the [shell theorem](_URL_0_). Essentially, there are two facts that can be derived from the math involved:\n\n1. Any spherically-symmetrical mass acts gravitationally as a point mass at any distance greater than that object's radius.\n\n2. A spherical \"shell\" of material acts as a point mass from the outside (same as point #1), but has *zero* net gravity on the inside.\n\nFrom those two facts, you can imagine what you would experience if you were to approach the sun vs. a black hole. From a distance, they both behave the same, gravitationally-speaking. As you pass the surface of the sun, though, its gravitational pull on you will start to weaken\\*, since the \"shell\" of material above you cancels itself out, and thus is no longer providing any gravitational force. However, at the same distance from the center of the equally-massive black hole, you're a **long** way from the surface, and so gravity keeps going up, instead of down.\n\nThe high density of a black hole makes it possible to get much closer to its entire mass without any of the gravitational force being negated due to the shell theorem.\n\n*****\n\\* *Depending on the actual densities involved, the gravitational force* may *still go up at first (I haven't done the research, but I know that this applies to the Earth), since the center of the sun is much denser than the surface. However, you will eventually pass a point where the gravity begins to drop.*",
"Physicist here. Just to add to this, the difference is the existence of an event horizon, and in this sense density is important. If you treated our sun as a point mass, it would have an event horizon. Basically, for any value of mass, there is a value of radius for an event horizon. But it's only the mass INSIDE that radius that counts.\n\nSo now the trick is how that mass gets inside the event horizon. That has to do with the balance of outward pressure (due to heat from fusion) and inward gravitational pressure. It can be shown that if a star has about 2-3 times the mass of our sun, gravity will eventually win."
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Shell_theorem"
],
[]
] |
|
9yiqx9
|
what’s the difference if any between working class and middle class?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9yiqx9/eli5_whats_the_difference_if_any_between_working/
|
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"Working class are people who have jobs, but typically low pay, low education jobs where they are just above poverty levels, not on welfare... but just barely scraping by. The fast food & retail workers, wait staff at a lower end place like diner or IHOP, hotel maids, low skill manual labor, warehouse workers, etc. They typically would rent a place to live, own an older, falling apart car, are in credit card or other high interest debt due to basic life emergencies (doctor visit, car break down).\n\nMiddle class are people with skilled trades, union jobs, or degree-requiring/managerial/professional type positions where they can adequately provide for their family, own a car or two, own a house, take a vacation, save for retirement, etc.",
"From a marketing perspective there is difference. In Australia, middle class make up the majority of people at 60% which is then split between middle and working class. There are different class structures which makes it a difficult answer but there is a difference in products sought, types of jobs, pay, and education in different classes.",
"For most intents and purposes, the working class is loosely defined as those who hold jobs with lower barriers to entry, that are usually defined by the work they entail. This does not strictly refer to wage, but more towards the type of job they hold. This means that, with proper saving, the working class can be middle class, but usually won’t be able to make upper class. Examples of these are oil field workers, construction, etc. Blue collar jobs often fit the criteria as well. \n\nMiddle class is where the wage comes into play. People that belong in the middle class usually do not have to worry about meeting monthly bills. ",
"In traditional economics, the working class works for a living, and has no ownership over their work. A waged or salaried worker would typically fit this category, regardless of how much money they make. A barista making minimum wage and an engineer making 150k/year would both be considered working class. \nThe middle class works for a living, and has ownership over their work. A small business owner who works at the business they own would fit into this category. Bob from Bob's burgers, for example. ",
"Middle class people are working class people who can afford to occasionally play at being upper class. For instance, they'll have some investments. Not nearly enough to stop working for a wage, but enough that they might have a stock broker, just like the \"big shots\". They can afford to take time off, and go on extended vacations abroad. They won't have second homes in Nice, but they might have a time share half an hour inland that they can pretend is all theirs for a week a year. They might have a maid that comes over once a month. They might go out to eat at a fancy restaurant every other week, or catch an occasional opera. They don't have to worry about being thrown out on the street if they miss a single paycheck."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
||
20n7v8
|
when high-level world leaders (like obama and putin) talk to each other on the phone, do they speak in the same language or do they need a translator? and if they need a translator, isn't that a serious security concern that someone knows everything they're saying?
|
And how do both countries agree on a common translator that they can both trust?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/20n7v8/eli5_when_highlevel_world_leaders_like_obama_and/
|
{
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"text": [
"I think the need for a translator greatly outweighs any security concerns. ",
"The translator only has to be trusted by the party that hires him. Usually Obama brings a Russian translator, and Putin brings and English translator. The translators work together and check each other to verify what the other is saying is accurate.\n\nA Presidential translator has passed the requisite security clearances and background checks to have access to the sensitive information that a President does. With those clearances and background checks comes an inherent trust and professionalism that the translator will accurately and faithfully represent what's being said.\n\nAlso, many foreign officials also speak English. I don't think Putin fluently speaks English, but many others do.",
"**Relevant:** Treaty of Nerchinsk. Treaty between Russia and the Qing empire in China, signed in 1689. The Qing spoke Manchu, and the Russians Russian, and neither side trusted each other to translate correctly. They ended up having to go through Missionaries on both side- Russian diplomat to Russian/ Latin Missionary to Manchu/ Latin Missionary to Manchu (Chinese) diplomat. Ultimately, the final agreement had to be written in five languages to be signed (Manchu, Latin, Russian, Chinese, and Mongolian). Arguably one of the oldest and most complex examples of accomplishing bilateral agreements while being impeded by severe language barriers.\n"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
1eq0kl
|
Did the Nazis negotiate with any official party abroad for the deportation of the jews prior to 1939?
|
First off, let me say that I'm not trying to stir up some Nazi propaganda by underhandedly asking a loaded "innocent" question.
I've been discussing the late Nazi grandmother of a friend, who held the conviction that the Nazi regime was actually trying to get rid of the jews in a "civil" (...) way before resorting to concentration camps and the Endlösung, such as deporting them to the US, GB, Palestine, ... and that these governments rejected that proposition for various reasons (resources, their own anti-semitism etc).
Is there any truth to that?
I'm hearing of this for the first time (despite being showered with WWII history in school as is common here in Austria) and I wondered if it wasn't taught because of the (seemingly) relativizing nature and/or it's irrelevance or if it's just a conspiracy theory.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1eq0kl/did_the_nazis_negotiate_with_any_official_party/
|
{
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"ca2nmkj"
],
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"text": [
"Sort of. They wanted it, and drew up plans for mass deporation to Madagascar. But the logistics would've been nightmarish, and IIRC would've required the ships of the Royal Navy, so it only would've worked after Britain being defeated. It wasn't much more than a pipe dream of getting rid of the Jews.\n\nThey also encouraged Zionism, as a way of getting Jews ideologically committed to leaving Germany. But due to unrest in Palestine, the British severely limited the number of Jews who could immigrate legally, effectively barring the area from being a place for Jews to go in the huge numbers needed. Jewish groups coordinated clandestine illegal immigration, but it was dangerous and limited in terms of how many people could move. It's worth noting, though, that if the Nazis had conquered Palestine they planned on killing the Jews there, too, not sending Jews there from Europe.\n\nThere was also the Evian conference, where a bunch of countries talked about taking in Jews from Germany pre-war, but when things were clearly getting bad for the Jews. A couple countries allowed a relatively small number, but due to nativism in general and antisemitism specifically very few countries let them in. The MS St. Louis is a particularly sad example of this. A bunch of Jews sailed around the western hemisphere in the late 30s, trying to find a country to take them in. None would, after Cuba revoked their visas. Eventually they returned to Europe, and about half were killed during the Holocaust."
]
}
|
[] |
[] |
[
[]
] |
|
903xe0
|
why do humans sometimes cant seem to remember whether they did something or not?
|
Especially the mundane things like remembering things like social security numbers/phone numbers/what I had for my meals.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/903xe0/eli5_why_do_humans_sometimes_cant_seem_to/
|
{
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"e2nk6zw",
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"text": [
"Isn’t it simply because we don’t pay attention? If you put down your keys absentmindedly it’s like overlooking something obvious: You’ll remember neither because you didn’t pay attention.",
"The purpose of memory is not to catalog everything about the past, but to help you survive in the future.\n\nThe brain is bombarded with information from all the senses all the time and most of it is basically irrelevant from a survival perspective, some of it is obviously very useful, and some of it is potentially useful but possibly irrelevant.\n\nAs it has to function in real time, the brain has to make rapid decisions about what to keep in memory and what to discard.\n\nIt’s pretty good at this (thanks evolution!), but inevitably will make mistakes- either remembering things which are of no use, not remembering things which would have been of use, or even misremembering things.",
"Short-term memory is limited, and the process of converting short term memory to long term memory is also quite power-consuming. If your brain deems something unimportant, or rather, requiring more energy to remember than it's worth, it'll drop the memory from your short term mind and *possibly* bury it deep within the long term memory, down into the subconscious levels. But we can still recall this information if we can recall other parts of the scene or if we're prompted. How it picks what to drop isn't really well understood but things like social security numbers and phone numbers are things you can retrieve by simply looking at where you wrote it down last, so instead of keeping the long, difficult to remember number in your head, it just stores the memory of where to find the number. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
2totq4
|
What are the differences of a Sherman tank and a Tiger tank?
|
After watching Fury, I recalled seeing a documentary about tanks a long while back.
What I'm wondering are the pros and cons of the Sherman and Tiger in relation to the time it was being used in Fury.
In my perspective the Sherman seemed weaker than the Tiger.
But is that true?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2totq4/what_are_the_differences_of_a_sherman_tank_and_a/
|
{
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"co0yqlj",
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],
"score": [
4,
3
],
"text": [
"This question comes up quite a bit. You might try [this link](_URL_0_) and [this link](_URL_1_) for your answer.",
"Assessing the \"value\" of a tank is far more complicated than people think. In the case of a tank you have to factor in several different things. Just to name a few.\n\n*Cost ( production, maintenance, milage, deployability et cetera )\n\n*Combat effectivness ( protection, gun, sights, rate of fire, mobility et cetera )\n\n*Usefullness in a strategic sense ( Whats the \"job\" of the vehicle?)\n\n*Combat readiness rate ( How much percent of the tanks are eventually engaging the enemy when needed.)\n\n\n\n > In my perspective the Sherman seemed weaker than the Tiger. But is that true?\n\nCertainly. One Tiger would outperform a Sherman in a duel situation. People who will argue otherwise are not studied on this subject. The Tiger was better armed and better protected there is also a case to be made for several other factors like gun sights for example. On top of that the Tiger has likely a far more experienced crew, maybe with dozen prior combat engagements since the Tiger was so well protected in 43/44 that a total crew loss was rare. The Sherman was able to deal with a Tiger in certain favorabler situations especially the upgunned version Firefly but overall the Tiger was superior in duel situations. ***But*** the Sherman was overall ( everything included) far cheaper than the Tiger. Combined with a higher readiness rate you had far more Sherman tanks to employ. Since tank on tank engagements are only a minor part of the tank duties and the difference of performance between a Tiger and Sherman in infantry support roles was likely \"comparable\" the Sherman had more impact on the battlefields than the Tiger for each dollar spent. So to summarize; with the Tiger you had a far superior \"tank on tank\" vehicle with likely only minor to medium advantages in Infantry support role ( the Tiger armor enabled it to take a beating of anti tank guns and infantry in general ) but for a far higher costs. To make up for this the Tigers which were available had to destroy ***a lot*** of enemy tanks to make up for all the Shermans helping the allied infantry. "
]
}
|
[] |
[] |
[
[
"http://www.reddit.com/r/AskHistorians/comments/2sjhq9/why_were_us_tanks_m4_sherman_still_inferior_to/",
"http://www.reddit.com/r/AskHistorians/comments/1x5lis/ive_heard_several_times_that_the_m4_sherman_tank/"
],
[]
] |
|
cy87lq
|
Why can't we synthesize the top shelf, super expensive, 40 years old scotch in the lab? Is there anything about the scotch only achievable by aging it more?
|
askscience
|
https://www.reddit.com/r/askscience/comments/cy87lq/why_cant_we_synthesize_the_top_shelf_super/
|
{
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"eyr62ur",
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7
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"text": [
"You could theoretically replicate expensive liquors in the lab, but we’re talking about a large amount of molecules you would need to add in a particular ratio to get the same result. This would be crazy expensive and in most cases you will end up with a different to slightly different product.\n\nAlso keep in mind that much of the price is due to marketing, so an identical liquor from “mylab” brand would most likely not fetch those prices unless you put in marketing effort.",
"The cost is more about the fact that you *have* spent 40 years aging it than the taste. 40-year-old scotch is in short supply and hence expensive. And because consuming rare things is at least partially a status thing, the cost is a *feature*."
]
}
|
[] |
[] |
[
[],
[]
] |
||
6i63j2
|
Why has (almost?) every currency lost so much value in the last century / last few decades?
|
A few hundred pound or dollars used to be an incredible amount in the 19th century, why did we let inflation take place so much to the point where pennies are near worthless in most if not all western currencies?
Was it to balance out unemployment, or just a part of a greater economic process?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/6i63j2/why_has_almost_every_currency_lost_so_much_value/
|
{
"a_id": [
"dj3t7d8",
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],
"score": [
4,
13
],
"text": [
"You may want to consider asking this in /r/Economics or /r/AskEconomics if you don't get an answer here. They may be able to provide you with answers related more to economic theory.",
"A history of monetary policy is necessarily very complex, and any account of it you receive here will be gross simplification and one that is very susceptible to a political bias. You'll probably have to read a variety of sources very critically to form a fair picture.\n\nThat being said, here's a take that would be fairly familiar to modern students of economics.\n\nThe monetary system is unavoidably complex. Governments generally attempt to keep it reasonably stable while accomplishing other goals. However the supply and the demand of money are both, in various ways, not under government control (because private lending changes the money supply in practice). \n\nIn the 19th and early 20th century, western governments chose to let inflation occur from time to time and deflation occur from time to time. The problem with this was that periodic deflation was hugely damaging to economic activity and caused banks, businesses and even farms to fail, sometimes even when they were generally productive. This was disruptive, but not in a \"creative disruption\" type culling out process of inefficient firms, just in a kind of random and uncontrolled way. \n\nThe alternative was to create government agencies and banking processes that controlled inflation and prevented deflation. These institutions could still not control changes in the rate of inflation entirely given other government policies. However, by letting inflation swing between zero percent and, say, six percent instead of between negative three percent and positive three percent, they could ensure that deflation did not occur. This means that there will always be some positive inflation, because whenever deflation looms, the government threatens to (or actually does) print money.\n\nOver decades, even a 0-6% inflation rate, which is barely noticeable in everyday life, will make the value of currency much less over a generation or two."
]
}
|
[] |
[] |
[
[],
[]
] |
|
go49t
|
What chemical property makes a drug 'addictive'
|
What makes opiates highly addictive for example, and other organic molecules not. What chemical interaction with the brain or molecular functional group determines this? Thanks
|
askscience
|
http://www.reddit.com/r/askscience/comments/go49t/what_chemical_property_makes_a_drug_addictive/
|
{
"a_id": [
"c1p11ig",
"c1p1adb"
],
"score": [
2,
4
],
"text": [
"Opiates activate the brain's [reward system](_URL_0_):\n\n > The mesolimbic pathway plays the major role, and goes from the ventral tegmental area via the medial forebrain bundle to nucleus accumbens, which is the primary release site for the neurotransmitter dopamine. \n\nDopamine is very important for pleasure and reward, and is also released in this pathway during pleasurable things like food, sex, and music. \n\nOpiates also activate this pathway, so both a physical dependence as well as a psychological addiction can arise from abuse of these drugs.",
"The following is horribly oversimplified. I wrote this several times, and this is the only version that's less than 60 lines in notepad.\n\nThere is no chemical structure common to all drugs that makes them addictive. \n\nAn analogy: Ever ripped a CD that was recorded too loud or too soft? When those songs come up on shuffle, you adjust the volume down, right? Or the TV commercials that are a lot louder than the show you're watching. You have to turn it down. Then the next song or your show comes back on, and you can barely hear it. So, you turn it back up.\n\nDrug addiction works the same way, just imagine the knob gets stuck after you repeat that process a few times.\n\nAny drug you take will hit a signaling pathway in your body. Often, the drug is \"louder\" than the normal signal in that pathway. In response, your body turns down the gain on that pathway. Now, when your normal signal comes through, it's hard to hear. At first, you can usually just adjust back. But for some pathways, the knob gets stuck after a while, so to speak. It gets to the point that the only way for that pathway to be heard is when that drug is used (you can only hear the loud songs). If the pathway is needed for normal functioning, the only way you can function normally is by taking the drug.\n\nRemember; this is a HUGE oversimplification. Read up on [receptor theory](_URL_0_) to get more. "
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Reward_system"
],
[
"http://en.wikipedia.org/wiki/Receptor_theory"
]
] |
|
2zcl50
|
Could a planet made entirely of metal achieve a stable orbit around a magnetar?
|
A [magnetar](_URL_0_) is a neutron star that emits an extremely powerful magnetic field, so could a metal planet orbit around it, or would the combined force of magnetism and gravity just suck it in?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2zcl50/could_a_planet_made_entirely_of_metal_achieve_a/
|
{
"a_id": [
"cpinx0t"
],
"score": [
2
],
"text": [
"See [this past thread](_URL_1_).\n\nThere can be no stable orbit in your configuration - see [Bertrand's theorem](_URL_0_)."
]
}
|
[] |
[
"https://en.wikipedia.org/wiki/Magnetar"
] |
[
[
"http://en.wikipedia.org/wiki/Bertrand%27s_theorem",
"http://www.reddit.com/r/askscience/comments/2mmhku/in_space_can_magnetic_material_orbit_a_magnet/"
]
] |
|
298i8k
|
Was there any connection between Mesoamerica and the Caribbean?
|
I recently learned that the Tainos also played a ball game ("batey"), and so I wondered in which extent these two worlds knew each other. I'm also interested in any interactions between the Caribbean and the rest of their neighbourhood.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/298i8k/was_there_any_connection_between_mesoamerica_and/
|
{
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"cij47qf",
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"I've heard some talk about it, but I haven't been able to find much. It seems they had extensive coastal trade routes and used some coastal islands as trading outposts, but they were hesitant to travel farther out than Guanaja or cross over from Cancún to Cuba.\n\nIt might be a little dated, but here are some excerpts from *The Ancient Sun Kingdoms of the Americas* by Victor Wolfgang von Hagen (1961)\n\nOn Mayan trade:\n\np. 269-270\n > The routes are best detailed in the Yucatán, for here the Mayas were concentrated in the last centuries of their cultural existence, and here they were conquered by the Spanish, who chronicled the details of their lives. Christopher Columbus was the first man to make a record of Maya trade. His caravels, on his fourth and last voyage to the Americas, met a Maya trading canoe on the isle of Guanaja in 1502. The canoes were forty feet long. They brought obsidian razors, copper hatchets, and cotton draperies of many different colors, and the Maya chieftain explained that they had come to this island, which lay twenty miles off the coast of Honduras, to trade for green parrot feathers and crystals.\n\n > When Cortés was in Xicalango in 1524, seeking the route to Honduras, one of the Maya traders there gave him a well-made map, painted on finely woven cloth, showing the entire inland routes through Mayadom, from Xicalango in Campeche to Nito, on the Gulf of Honduras, a distance of four hundred land miles.\n\n > All sea or land communications led to the great emporium of Xicalango. To the Aztecs it was Anáhuac Xicalango and called \"the place where the language changes,\" that is, the tribes to the southeast of Xicalango spoke Maya.\n\n > Xicalango lies a few miles inland from the Laguna de Términos. Into this outsized lagoon debouch four rivers, the largest of which is the Usumacinta. At the northeast end of the forty-mile-long lagoon there is a smaller one, the Laguna de Pom; on its shore was Xicalango. It was strategically placed. To reach it traders coming southward had to use canoes. It was surrounded on three sides by bog and swamp. On the northeast side there was a causeway leading to Vera Cruz and Aztec Mexico. Xicalango was a meeting place of Maya, Aztec, Toltec, Mixtec, and Totonac.\n\nOn Mayan sea communications, p. 373-375\n\n > The Mayas also used the sea road, which required no upkeep. They and they alone of all the great civilizations of the Americas were a maritime people, going out in large ocean-going dugouts, traveling over thousands of miles of coastal sea.\n\n > The first thing that Columbus met when he landed at Guanaja in 1502 were Maya boats. At one of the islands he saw and examined one \"as long as a galley, eight feet in breadth, rowed by twenty-five Indian paddlers,\" and laden with commodities--cacao, copper, bells, flint-edged swords, cotton cloth--brought from the mainland, twenty miles distant.\n\n > As Spanish voyages began to multiply, others reported seeing immense dugout canoes that held as \"many as forty Indians.\" In 1542 at the siege of Omoa, a trading colony in Honduras, fifty war canoes were sent at one time all the way from Chetumal, a distance of over two hundred sea miles, to aid in resisting the conquistadors. Many of the early Spanish accounts mention the tremendous number of canoes and the amount of canoe traffic along the entire coast from Tabasco to Panama.\n\n > The Maya canoe(*chem*) was usually made from cedar, and carved out of a single tree trunk often as long as eighty feet. It was built with a high bow and stern more or less as the Mayas have themselves pictured it in the murals of Chichén Itzá.\n\n[...]\n\n > Between A.D. 400 and 800 Tikal and other interior cities had contact with the sea, using the river roads that emptied into Chetumal Bay. Farther north at Bahía de la Ascensión--anciently, Zamabac--was a place for the embarking of \"maritime traffic destined for Honduras and other regions south\" [*The Indian Background of Colonial Yucatan, p.548*]. By the time of the Spanish arrival, circa 1511, trade had shifted farther north to Tulum.\n\n[...]\n\n > The whole coast about the Laguna de Términos--where Xicalango was located--was a network of rivers, bayous, and creeks. A Spanish map of the seventeenth century shows inland waterways and describes in detail routes by narrower channels, such as appear on the Florida coast where boats of small draft can move without actually going out into the open sea. This coast was difficult for European ships, which had to stand out to sea, but not for the Maya dugouts.\n\n > Inland waterways led to Usumacinta River, up which (by portage and prayer) the Indians managed to navigate two hundred miles. The rivers of Honduras were navigable for canoe traffic many miles inland, and salt, for example, was carried in sacks direct from the Yucatán salt ponds to the interior of Honduras. There the sacks were filled with cacao and obsidian for the return voyage. The whole coast was a Maya economic bloc with some concessions to the Nahuatl-speaking traders from Xicalango. Seafaring was coastal. Signs were erected, feather banners, to help sailors navigate the flat shore. The murals of Chichén Itzá, which illustrate Maya canoes, also show signs that could be so interpreted. \n\n[...]\n\n > There were limits to Maya seafaring. There is no evidence that the Mayas had contact with Cuba, even though it is only 125 miles away, perhaps because a bewildering and dangerous current runs between Cuba and Yucatán. Yet there was an occasional accidental, if not purposeful, contact with the Antilles. Bernal Díaz met at Cozumel Island \"a good-looking Indian woman\" who--spoke \"the language of the Island of Jamaica . . . As I . . . knew the language . . . we were very much astonished, and asked the woman how she happened there. . . . two years earlier she had started from Jamaica with ten Indians in a large canoe intending to go and fish . . . the currents had carried them over to this land where they had been driven ashore . . . her husband and all the Jamaica Indians had been killed and sacrificed to the Idols.\"",
"There's evidence, however scant, that some level of contact did exist between the Yucatan and Cuba. The problem is that this evidence is very slight. [This article from FAMSI](_URL_0_) is one of the better summations of evidence of Meso-Carib trade, but even it has to note that the evidence comes down to a few cultural artifacts (like the ball game) and even less physical artifacts (like \"vomit ladles\"). \n\nThe article does correctly note that any travel between Mesoamerica and the closest Caribbean island (Cuba) would have necessitated a several day journey at sea out of sight of land. While circum-Yucatan trade routes are attested down to the coast of what is now Honduras, these routes were (like many ancient trade routes) based upon keeping the coast in sight. Open water sailing is a skill more difficult to develop and learn than most people would think. The Caribbean itself was most likely [peopled from South America](_URL_1_) along a route that allowed a great deal more island hopping than a Meso-Carib route provides.\n\nSo while there is some evidence that a few intrepid traders from Mesoamerica did interact with the Caribbean, the problem remains that this contact does not appear to have been much more beyond that. Cultural artifacts like ball games are much more easily adopted than physical practices. Mesoamerican merchants simply had more lucrative options for martime trade down along Central America and overland trade up to the US Southwest (were ball courts and Mesoamerican iconography can be found)."
]
}
|
[] |
[] |
[
[],
[
"http://research.famsi.org/aztlan/uploads/papers/Canter-Yucatan-Channel-and-Trade.pdf",
"http://www.ncbi.nlm.nih.gov/pubmed/11427174"
]
] |
|
34qd1a
|
Why do guns have such bizarre calibers?
|
Everything is in this weird hundreds of millimeters or thousands of inch tolerances, and it just baffles me. Why .308 instead of .300? 5.56mm? Why not 5mm or 6mm? And, I know it's the same size as .223, but still, why not .25? It's all this weird mishmash of calibers, and that's not even discussing the weirdness of round length.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/34qd1a/why_do_guns_have_such_bizarre_calibers/
|
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"text": [
"fyi, you may be interested in some previous posts\n\n* [Why have such unique caliber firearms become more popular instead of nice, rounded numbers?](_URL_0_)\n\n* [How did calibers in uneven numbers come about? Like 152mm, 37mm and 76mm?](_URL_1_)\n",
"This is a question that's not very related to history, perhaps it would be more suited to /r/askengineers. \n\nSeveral of these calibers come from converting imperial dimensions to millimeters.\n\n152 mm = 6\"\n\n6.35 mm = 1/4\"\n\n5.56 mm = 0.22\"\n\n7.62 mm = 0.30\"\n\nAnd several others.\n\nHowever, note that these aren't necessarily the *exact* diameter of the barrel. Even if you used the exact value, where would you measure it, a rifled barrel has lands and grooves.\n\nIn the end, there's no true need for round numbers. If you check engineering specifications of any machines, not necessarily guns, you'll find a lot of odd-sized dimensions.\n\n",
"I asked this question a while ago, the best answer I got was:\n\nI think originally the reason for these odd sizes is because bullets were ball shaped and were measured not by caliber but by the pound. Early muskets and flintlocks used spherical lead balls, which were measured by how many equal sized balls you could make with a pound of lead, much the same way buckshot or birdshot is measured today.\n\nSo, for example, a 2 oz ball (8 to the pound) is 8 gauge, or 0.835\" in diameter, or a 1 oz ball (16 to the pound) is 16 gauge, or 0.662\" diameter. When you get to smaller diameters, you are in the realm of buckshot or birdshot. For example, 0000 buckshot is 0.38\", 0 buckshot is 0.32\", #4 buckshot is 0.24\", to name some common diameters for bullets used today.\n\nSuch spherical balls were used through the early centuries of firearms, in fact up to the early 1820's, when conical bullets were invented. But even much later, spherical bullets continued to be very common, such as in the widely used ball-and-cap pistols in the Civil War.\n\nThese early guns were not very precisely bored, so it can be deceptive looking at very precise numbers like 0.662\" and thinking \"wow, that must have fit a gun with a 0.662\" bore\". In fact, bore size only roughly approximated the bullet and accuracy was low at large distances.\n\nAfter conical bullets were invented, there was no reason to stick to the old \"how many balls per pound\" method of sizing bullets. Some of the variation is for historical reasons. For example, there was originally the .38\" bullet, that was designed for use in a black powder cartridge. Since black powder is weak, the manufacturers tried to squeeze in as much as they could, which they did by giving the bullet a very short \"heel\" or narrowed section that fit inside the brass. This left the bulk of the brass free to cram in lots of black powder. But later when smokeless powder was invented, this was no longer needed, so they seated the bullet more deeply in the brass - in fact, the whole bullet became the \"heel\". And it so happens that when you reduce a .38 bullet by the thickness of the brass, it becomes .357, which is a popular caliber today.\n\nIn the same way, a .44 magnum is really a .429\" bullet that also reduced its size during the switch from black powder to smokeless powder. So it's not that someone decided \"we're going to specify this bullet with 3 digits of precision because that makes for a great bullet\", but rather, it was just a historical artifact of a change in process/materials.\n\nAnother thing to remember is that sometimes bullets were deliberately bigger or smaller than the designed bore for other reasons. For example, for a patched round ball the ball may actually be smaller than the bore, with the idea being that the patch makes up the difference. In other cases, the bullet may be slightly bigger than the bore, again with the idea that chambering it slices off a sliver of lead and ensures a tight fit. So you may have a bullet that's .002\" bigger or smaller than the bore, and you wonder why it needs a 3rd digit of precision, did the manufacturers hate round numbers? But it has to do with the fact that the bore is already specified in round numbers, and now you are adjusting up or down from that for particular reasons.\n\nI don't think there is any single answer for why such weird numbers for bullet calibers. It's basically a matter of long histories and the various changes that have happened during that time to manufacture, materials and technology, which have resulted in the actual calibers that are popular today.\n\n\ncredit to /u/EvanRWT for knowing his shit ",
"A dizzying array of calibers were made in the past, and the ones that survived were simply the ones that the public liked. A LOT started with the rimfire .22 .32 .38 .44 (dont ask me why). I think Smith & Wesson created those. The .22 still exists today as the .22 short. When customers wanted a .22 with more power, they elongated the brass case to allow more powder, so instead of the just the .22, they re-named the original the .22 *short*, and the new one was the .22 long. You can shoot a .22 short in a revolver and some lever-action rifles, but they will not interchangeable in semi-auto pistols and rifles.\n\nThe other rimfires fell by the wayside, more powder meant that the copper case might split at any place in the case, and sometimes some of the blast would be directed back through the cracks in the weapon to burn your hand or face. The entire case was extruded and formed from a single piece of copper alloy, so for the rim to be able to be crushed by the hammer (igniting the priming crystals, mercury fulminate [see breaking bad/Tuco]), the rest of the case was also weak.\n\nHowever, there was significant expensive tooling at the factory for cutting .32 .38 .44 cylinders and barrels. Colt had patented the .36, .41 and .45 calibers (for a short time), so even after buying the pistol, you couldn't buy ammo from anyone else (for at least a few years, until the patent expired).\n\nBy combining the primer cap (made from crushable copper alloy) from the existing cap-and-ball firearms, but with the stronger brass material in a case similar to the new and popular rimfires, you could have a more powerful cartridge. Whether for a pistol or rifle, the new brass cases were immediately popular.\n\nSmith & Wesson got the huge and desirable Russian army pistol contract, so their .38/.44 \"top break\" pistols production was pretty much spoken for. When the US Army put out a bid for a pistol, the Colt \"Single Action Army\" (SAA) won the contract. However, several years later, customers asked for a Colt in the most popular rifle cartridge (1873 Winchester .44 centerfire), which would allow someone with a pistol and rifle to only need one caliber, so as soon as the S & W patents expired, Colt made the \"Frontier\" model (an SAA in .44 instead of .45).\n\nThe bullets were lead, with no copper jacket. Frontiersmen could dig out a bullet from a deer and re-melt it into a mold to re-load new cartridges. The lead would build up inside the barrel and need to be cleaned out. The .22 rimfire had a recessed base so that the slug walls were the same diameter as the copper case, and thats when ridges and grease were added to the slug-sides to reduce lead build-up as the slug passed through the barrel. \n\nWhen brass cases were introduced, the case diameters were kept the same to continue to use the same machines, but...the bullet slug diameters were reduced (along with the barrel IDs to fit), and the greased ridges on the newer smaller-diameter slugs was placed at its base, so the ridges and grease were inside the brass case, to prevent dust and sand from sticking to the slugs when traveling.\n\nThe bases of the bullets are what expanded into the barrel rifling to grip the grooves (like a hammer mushrooming a spike head), so having only the base greased worked well enough. Traveled well, clean and dry, didn't build up much lead in the barrel when shot.\n\nIf the cases were still .38 and .44...the new bullet sizes (slug outside diameters to match the IDs of the cases) turned out to be .357 and .429\n\n",
"Part of the weirdness is from the fact that rifled guns have three different diameters that are important to the functioning of the rifling, and while one might be a nice round number the other two might not be. The [three diameters](_URL_5_) are the diameter of the bore, the diameter of the rifling, and the diameter of the bullet. For large artillery caliber is given in bore diameter because a driving band is used to fill the rifling, but in small arms the bullet itself deforms to fill the rifling. Usually a caliber for a rifled gun is done a nice even bore diameter in metric, imperial, or customary and then the [bullet is slightly larger to fill the rifling](_URL_4_) when it deforms, but because there are only so many useful even bore diameters there are multiple different cartridges at that bore diameter. So to differentiate between these cartridges the length of the cartridge or whether it is rimed or not is used, but sometimes the actual diameter of the bullet is used. For example using five similar cartridges all of which use a .3 inch diameter bore: [.308 Winchester](_URL_7_), [.300 Winchester Magnum](_URL_6_), [7.62×51mm NATO](_URL_1_), [7.62×54mmR](_URL_0_), [7.62×39mm](_URL_2_). If you look at the .308 Winchester and the .300 Winchester Magnum the actual bullet diameter and bore diameter is the same even though they have different numbers is the name. The .308 Winchester and 7.62×51mm NATO even have the same exterior physical dimensions. For 7.62×51mm NATO, 7.62×54mmR, and 7.62×39mm you can see how two cartridges that have the same nominal diameter can have different bullet dimensions and cartridge length and rims.\n\nAnd your nice round bore diameter might not be nice and round in another unit system as /u/MasterFubar mentioned in his comment about converting from one to another, such as:\n\n152 mm = 6\"\n\n6.35 mm = 1/4\"\n\n5.56 mm = 0.22\"\n\n7.62 mm = 0.30\"\n\n**Edit:** Forgot to mention but the length of the bullet determine how heavy the bullet will be and the length of the whole cartridge determine how much gunpowder there will be, usually also done in nice round numbers subject to the same change in unit system problems at the bore and bullet diameter.\n\n**Edit2:** After reading the comments by /u/spinningmagnets and /u/CherrySlurpee I am wondering if some of the large number of weird calibers were based off of fractions of a pound and whatever kind of bullet could be made with X amount of lead was done, because the .22, .32, .36, .38, and .41 calibers are not really logical even in customary. My searched turned up nothing but [.44-40 Winchester](_URL_3_) started as a 200 grain bullet with 40 grains of black powder, giving nice even numbers, which is why I am wondering."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/1wbwxn/why_have_such_unique_caliber_firearms_become_more/",
"https://www.reddit.com/r/AskHistorians/comments/1upe0s/how_did_calibers_in_uneven_numbers_come_about/"
],
[],
[],
[],
[
"https://en.wikipedia.org/wiki/7.62×54mmR",
"https://en.wikipedia.org/wiki/7.62×51mm_NATO",
"https://en.wikipedia.org/wiki/7.62×39mm",
"https://en.wikipedia.org/wiki/.44-40_Winchester",
"http://s706.photobucket.com/user/hasselblad/media/LandsandGrooves.jpg.html",
"http://www.navweaps.com/Weapons/Gun_Data_grooves_pic.jpg",
"https://en.wikipedia.org/wiki/.300_Winchester_Magnum",
"https://en.wikipedia.org/wiki/.308_Winchester"
]
] |
|
3yhcee
|
why do bagels and donuts have holes?
|
Why can't they be just completely shut?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3yhcee/eli5_why_do_bagels_and_donuts_have_holes/
|
{
"a_id": [
"cydhcfa",
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"cydi8ey"
],
"score": [
25,
3,
2
],
"text": [
"They have holes so that they will cook evenly. Without the holes, there would be a doughy center that you wouldn't find appealing. ",
"Donuts do come without a hole. In American tradition, its made with the hole.\n\nBagels without a hole are bialys, traditional food of Russian Jews. The ones you buy are made with the holes because that's what sells here",
"So they cook evenly. Donuts are made, and have the hold punched, while Bagels are \"rolled\" around a post to make them round. This is why you typically have a thin spot on a bagel.\n\n[Video of a bagel being rolled.](_URL_0_)"
]
}
|
[] |
[] |
[
[],
[],
[
"https://youtu.be/4-BOY7lBqlc?t=1m55s"
]
] |
|
floc2
|
What is the biological reasoning behind the frustration that you can feel in the middle of your chest?
|
Why do we feel it only at the chest? Does some sort of acid build up?
|
askscience
|
http://www.reddit.com/r/askscience/comments/floc2/what_is_the_biological_reasoning_behind_the/
|
{
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"c1gupxi",
"c1gusdo",
"c1gv57z"
],
"score": [
2,
5,
20,
2
],
"text": [
"I think it's the effect of adrenaline on your heartrate.",
"This is something I've always wondered as well. Strong feelings of things like frustration, shame, embarrassment and regret all seem to make something in my chest feel ignited. Negative emotions can sometimes feel physically painful when they are strong enough. I'd love to learn more about the science behind things like this. Any good books out there for the uneducated?",
"\nStress releases epinephrine increasing heart rate and constricting blood vessels, norepinephrine activating the amygdala and increasing heart rate, and cortisol which will increases stomach acid and blood pressure. It is likely you feel it most in the chest because the heart and esophagus are under increased load and have nerves bundled together.",
"If it's a physical pressure you feel, then more likely it's the thoracic duct rather than the heart. The td can and does get blocked: blood vessels less so! "
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
6zs0ux
|
what happens if someone from an uncontacted tribe wants to join society? are they citizens of the country they live in?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6zs0ux/eli5_what_happens_if_someone_from_an_uncontacted/
|
{
"a_id": [
"dmxm3xu"
],
"score": [
7
],
"text": [
"Aye. Every country I know of grants citizenship automatically to people born on their soil from ancestors also born on their soil (unless, an exception in some countries, those ancestors were explicitly guest immigrants)."
]
}
|
[] |
[] |
[
[]
] |
||
8mmi4k
|
why do video players always require user action after they start buffering? almost every application, youtube, ifunny, reddit, needs me to press pause and play after loading instead of just starting the video again. why?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8mmi4k/eli5_why_do_video_players_always_require_user/
|
{
"a_id": [
"dzosvbj",
"dzou1cc"
],
"score": [
3,
6
],
"text": [
"Do you have any kind of click-to-play addon/plugin installed?",
"Be careful what you wish for.\n\nThe current behaviour, as I understand it, was in response to large numbers of users **complaining** about auto-play; people **wanted** to control when videos started, and not have three of them playing simultaneously.\n"
]
}
|
[] |
[] |
[
[],
[]
] |
||
1q2e8j
|
Is there any evidence to the idea that Muhammad established the Hajj as a Pillar of Islam in order to gain support from the powerful merchants that 'ran' the city?
|
I was having a discussion with someone, and his argument was that the Hajj was established to continue/mimic the earlier 'pagan' tradition of Mecca, but also to gain support from the traders and merchants who would profit enormously off of the annual influx of people.
I was curious, and maybe a little skeptical, because it had always seemed to me that Muhammad represented a near-total break with the earlier traditions and religions of the area, especially as he destroyed all of the 'idols' at the Kaaba and threw out the leaders of Mecca. But then again, it is not my area of expertise, so I thought I'd ask!
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1q2e8j/is_there_any_evidence_to_the_idea_that_muhammad/
|
{
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"cd8mxkp",
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"text": [
"I'm not certain if this is an appropriate top tier comment, but would also like to ask another question on the background of this line of questioning. How much archaeological and other historical evidence and records do we have of Mecca in the pre-Islamic era? Do we even know for certain whether Mecca was much of a major trade hub at the period?",
"The Ka'aba was an extremely important part of pre-Islamic Mecca. It was a focal point for pagan religious pilgrimages then in the same way that it is now for Islam. At the time there were idols for all sorts of gods there. This religious significance is more or less the only reason Mecca, which is in the middle of a desert, was a thriving merchant city at the time. So in that sense the Hajj isn't too different from what was going on before Muhammad rose to power. What's important to understand about paganism is that it didn't operate on the same principal of exclusivity as the major monotheistic religions. People didn't generally get nasty with each other over whose gods were the right gods -- there were just a bunch of gods and people had an affinity for different ones based on whatever their personal beliefs were. So when Muhammad came along, the crucial break with earlier traditions was to say that it isn't okay to just pick and choose and have shrines for many pagan gods because God (Allah) essentially embodies every pagan god combined into one plus more. But he didn't really change what the actual physical act of pilgrimage entailed. So the Ka'aba didn't change its function, it just became a shrine to the one true God (according to Muhammad) instead of a bunch of pagan gods. I don't think the Hajj was supposed to appease merchants or anything like that, because it isn't fundamentally different from what people in the area already did before Islam was established. And like you said, Muhammad ran the merchants who were in charge of Mecca out of town when he took over (albeit only initially). \n \nFor more deets on this and the early history of Islam in general, I recommend the very accessible *No god but God*, by Reza Aslan. It's a bit of a love letter to Islam so you have to be aware of the bias, but it's a good source for familiarizing yourself with the history of Islam on a basic level as well as its role in the present day geopolitical climate, and I found it to be a quick and enjoyable read."
]
}
|
[] |
[] |
[
[],
[]
] |
|
3i4bkf
|
why does holding the little wire antenna on a clock radio in your hand increase the quality of reception?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3i4bkf/eli5_why_does_holding_the_little_wire_antenna_on/
|
{
"a_id": [
"cud5wp9",
"cud65b9"
],
"score": [
2,
2
],
"text": [
"Because then your body becomes part of the antenna. So, instead of a few inches of antenna, there's now five to six feet worth of antenna.",
"You're an antenna. Not a good one, but big. Your bloods and cell fluid have salt in them and that means they conduct electricity. Radio signals can propagate better in conductors. In conductors, the electric field wave in a radio wave can move the electrons a very little bit, to give a pretty big change in electric field that propagates to the other end of the piece.\n\nA mechanical analogue is a Newton's cradle, where a pressure wave can propagate through multiple steel balls to propel the last ball up.\n\nThe current involved in very small, so it's not dangerous."
]
}
|
[] |
[] |
[
[],
[]
] |
||
2k2skd
|
what's the healthiest kind of milk and why?
|
Out of the milks available at the average grocery store, and why?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2k2skd/eli5_whats_the_healthiest_kind_of_milk_and_why/
|
{
"a_id": [
"clhfy4b",
"clhm82x"
],
"score": [
2,
2
],
"text": [
"Human breast milk. It's nutritionally complete, but is formulated for babies which grow extremely quickly in their first year or so. Chances are if you drank enough to sustain you there'd be more fat than an adult would require. Therefore I restate my original suggestion as \"low fat human breast milk\".",
"human is the only animal that uses milk after weaning- raw goat milk is very close to human milk, I have rescued orphan baby animals using raw goat milk- must be RAW"
]
}
|
[] |
[] |
[
[],
[]
] |
|
3gup5w
|
What makes a 'supercomputer' special as compared to a networked server farm?
|
Supercomputers are built by combining thousands of processing cores together, right? When programming for supercomputers, you already have to be doing massively parallel calculations. Most are using standard, off the shelf commercial grade CPU's and GPU's these days. Its not like the 90's where there was special CPU architecture. What is stopping Google/Amazon/Microsoft/Whoever from opening up their cloud computing platforms as for-pay supercomputing?
|
askscience
|
http://www.reddit.com/r/askscience/comments/3gup5w/what_makes_a_supercomputer_special_as_compared_to/
|
{
"a_id": [
"cu1q0md",
"cu1q189",
"cu1r2ld",
"cu28fzo"
],
"score": [
4,
2,
29,
3
],
"text": [
"Actually Google did lend one of their supercomputers for calculating the maximum amount of moves needed to solve any rubiks cube scramble (kinda off topic, but I'll put a source when I'm not on mobile). The answer turned out to be 20. Anyway, supercomputers and servers aren't really the same thing. Modern supercomputers are built to optimize problem solving/difficult calculations. Servers on the other hand (for websites), typically aren't built the same way. Servers are built to handle large load from users, for this the server needs to be able to output data quickly. \n\nSo lets say I log in to my Google account, and try to edit one of my google docs. The server needs to:\n\n1)Authenticate your credentials\n\n2)Access your google doc's data (the text and information inside of the document)\n\n3)Output it to the user, for editing and previewing.\n\nThis is **not** the same as calculating large numbers for mathematics problems. I hope this answered your question. If I'm wrong about something please correct me.",
"[Amazon](_URL_1_), [Google](_URL_2_), and [Microsoft](_URL_0_) do open up their cloud computing platforms as for-pay supercomputing.\n\nWhat makes a \"true\" supercomputer special? The major difference is that the cloud is physically spread out, so inter-process communication is slower. For something like a database query, where records might be shipped back and forth often for processing on different nodes, the delay can be a significant issue.",
"It's largely additional investment in high speed connections between machines. \n\nSupercomputers use something like [Infiniband](_URL_3_) for extremely fast low latency communication between the machines. For example, say you want two 8-core machines to work together on a problem. If it takes a long time (milliseconds) to transfer data between them it will actually be slower than only using one because there is so much waiting for information. \n\nIf you were solving thousands of versions of [relatively small models](_URL_1_) (maybe varying thicknesses, diameters, etc.), something like Google's data center would be great. You could solve each version independently on its own machine (~8 cores) and get all of the results at the end. \n\nThe other type of problem is something [very complex that you only solve a few times](_URL_0_), and each solve uses dozens of computing cores. Google's data center would probably be terrible because the machines couldn't talk fast enough to be effective. \n\nSome data centers are starting to migrate to [100 Gigabit Ethernet](_URL_2_) (a competitor to Infiniband) so the lines are blurring even more. At that point it's mostly software differences. (Edit: see /u/tejoka's comment below, there's more to it than just software). \n\n",
"The key difference is how the system treats memory.\n\nIn a supercomputer special high speed interconnects are used which allow for memory to be shared between multiple processors very rapidly. The fabric contains special processors for distributing memory among processors and reporting on the performance and health of the distributed system\n\nIn a normal datacenter, network attached and directly attached storage are available for use by individual servers.\n\nImportantly, most modern supercomputers are distributed, meaning that there are different tiers of memory available. A group of processors might have local memory they share, and then a group of groups has a different section of memory available at a lower speed, and then there may be globally available memory. A huge number of processors take advantage of this architecture to jointly process the problem. \n\nVector supercomputers tackle problems that aren't appropriate for paralellization. They have a single memory domain and effectively act as one very fast processor with a lot of RAM. Cray is famous for their vector supercomputers.\n\nThis is my moderate understanding from my time at NASA and AWS. NUMA is a common technology you can Google that will give you an idea of the problem space. There are many different approaches to distributed computing, and researchers use reserved IOP systems from AWS for instance to perform research all the time. This approach is not optimized like a supercomputer is because the high speed distributed memory that exists in a supercomputer is not available. AWS also offers high performance local cluster options that guarantee a set of virtual machines or instances will be local to one another and therefor have lower latency. This combined with provisioned IOPs (dedicated storage bandwidth) allows for pretty high performance computing, but at a price.\n\nTLDR; distributed supercomputing needs fast storage and low latency shared memory. Cloud computing can get you decent specs on both, but dedicated supercomputers are way faster on both metrics as they are purpose built."
]
}
|
[] |
[] |
[
[],
[
"https://azure.microsoft.com/en-us/services/batch/",
"https://aws.amazon.com/ec2/",
"https://cloud.google.com/compute/"
],
[
"http://www.sandia.gov/~sjplimp/images/pronto_foam.gif",
"http://www.sigmak.ltd.uk/sitepix/images/cast-Iron-valve.jpg.ashx?w=410",
"https://en.wikipedia.org/wiki/100_Gigabit_Ethernet",
"https://en.wikipedia.org/wiki/InfiniBand"
],
[]
] |
|
203rkn
|
How do you measure the velocity of a galaxy?
|
We believe the universe is expanding based on the fact that Hubble(along with other scientist through the years?) have measured the velocity of galaxies and have observed that they're moving away from us. How were these measurements taken?
|
askscience
|
http://www.reddit.com/r/askscience/comments/203rkn/how_do_you_measure_the_velocity_of_a_galaxy/
|
{
"a_id": [
"cfzm31b"
],
"score": [
2
],
"text": [
"Hubble measured the velocities using the Doppler effect for light. Various atoms and molecules emit light at known characteristic wavelengths. If something is move away from us or towards us, we'll see those wavelengths shifted. There's a nice description [here](_URL_0_)"
]
}
|
[] |
[] |
[
[
"coolcosmos.ipac.caltech.edu/cosmic_classroom/cosmic_reference/redshift.html"
]
] |
|
3zpxma
|
Was the arab world in Nassers time like a single nation of brothers?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3zpxma/was_the_arab_world_in_nassers_time_like_a_single/
|
{
"a_id": [
"cyo3chu"
],
"score": [
11
],
"text": [
"Not at all. There was lip service paid to Pan-Arabism and unity, but Arab states still routinely conspired against one another. Nasser's brief union with Syria was a disaster, the Syrians and Egyptians spent its entirety politically squabbling and trying to usurp the other. The attempted union between Jordan and Iraq had similar results. The Saudi's and Egyptians waged proxy wars in Yemen. Jordan and Syria came to near-blows. The PLO created a soft-apartheid regime that discriminated against non-Palestinians and Shia's in Southern Lebanon and attempted to do the same in Jordan. Fabulous speeches was given to supporting the Palestinians and destroying Israel, but policy regarding that differed wildly from Arab state to Arab state.\n\nUltimately one only needs to see the truth of the situation by realizing that the bloodiest wars of Nasser's time were not the Arabs engaging in a common struggle against the Imperialists or Israeli's, but rather each other. \n"
]
}
|
[] |
[] |
[
[]
] |
||
cbw5s6
|
Why do Italian cities change their names in English, but other countries like Spain and France retain the native name for their city?
|
Not sure if this is the right subreddit to ask this is but I've always been curious if there's a historical reason for the change. A lot of Italian cities like Fiorenze, Roma, Milano, Napoli etc change their name in English. In Spain I can only think of one: Sevilla. In France I can't think of any. They are all similar Latin languages so why the change only for Italy?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/cbw5s6/why_do_italian_cities_change_their_names_in/
|
{
"a_id": [
"etkzqvb",
"etl0p6s"
],
"score": [
20,
90
],
"text": [
"I can maybe help with a perspective from the other side. In Italy a lot of city names from UK, Germany and France are Italianised: London/Londra, Berlin/Berlino, Paris/Parigi. \nIt was a typical thing until at least the 1500s so cities that were part of everyday conversation were 'adapted' to sound less foreign. Spanish cities were asked too but that's less obvious as the pronunciation is already pretty similar Barçelona/Barcellona, Sevilla/Siviglia. On the other hand cities that entered common lexicon later on have more or less retained their original pronunciation: New York, Sydney, Tokyo\n\nThere are exceptions but that's a more or less general rule which I think could work in English as well",
"First of all, this is not true exclusively of Italian cities. Other citiies like Copenhagen, Prague, Moscow, and Belfast also have names significantly different in their source languages (København, Praha, Moskva, Béal Feirste).\n\nWhy? Four reasons. The first is normal sound changes in English. All words in the language are subjected to these, even the names of cities, and the longer the city has had a name in English, the more sound changes it would have gone through. So an old famous city is more likely to have experienced more sound changes. Even English cities are subject to this - Manchester was *Mameceastre* in Old English, for example.\n\nThe second is sound changes in the foreign language that occurred after the name was established in English. This is a particularlarly large factor in Italian cities. Florence, for example, used to be Florentia in Latin. English has actually preserved a much closer version of that than Italian has. And why is Livorno called Leghorn? Because only a few centuries ago it was called Legorno in Italian. (And actually, the discrepancy with the Italian name is getting too large, and Leghorn is not famous enough for its English name to have much inertia, so the use of the name Leghorn is dropping off in English as the word is reimported as Livorno.) \n\nThe third is sound changes in intermediate languages. English borrowed a lot of words from French, which went through very extreme sound changes from the original Latin over the last 1500 years. Not to get too far off track, but that's why we often have two versions of some Latin words in English - one borrowed directly from Latin (e.g. masculine) and one borrowed from French after that same word has been put through the meat grinder of French sound changes (e.g. male). So some Latin cities like Roma were actually changed in French, e.g. to Rome, and then borrowed to English. This is also true of Venice, where the change from Venetia to Venice happened in French, while a different change in Italian led to the modern Venezia. (In the case of Copenhagen, we borrowed the German name for the city rather than the Danish one.)\n\nLastly, there is also simple Anglicization, in which the city name is altered to make it simpler for people accustomed to English phonology to pronounce. This is the case in many Irish and Scottish cities, but also true to a lesser degree in Italy. In Italy it was normally a case of lopping off the vowel at the end, as Italian phonology is in general not difficult for English speakers to approximate, except for maybe the initial \"gl\" sound. So Latin Syracusae became English Syracuse (and Siracusa in Italian)."
]
}
|
[] |
[] |
[
[],
[]
] |
|
6lkvtf
|
how to find out foreign last names?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6lkvtf/eli5_how_to_find_out_foreign_last_names/
|
{
"a_id": [
"djuk75c"
],
"score": [
2
],
"text": [
"Just ask. No-one should be expected to know how names work in N+ different cultures.\n\nBesides, if you meet \"Jack Norton\", and refer to him as Mr. Jack, They are most likely amused, before correcting you. Amusement is a good icebreaker, I've found."
]
}
|
[] |
[] |
[
[]
] |
||
gwwmj
|
Why does music sound so much faster to me when I first wake up?
|
I know one of my friends has experienced this as well, although I have heard people have this happen late at night as well.
|
askscience
|
http://www.reddit.com/r/askscience/comments/gwwmj/why_does_music_sound_so_much_faster_to_me_when_i/
|
{
"a_id": [
"c1qw778"
],
"score": [
12
],
"text": [
"Your mind has a rhythmic expectation that affects how fast or slow it perceives reality. If you play a computer game, try this cool trick to observe a similar effect:\n\nWatch a replay in that game at 2x speed for about 20 minutes and then play a game at normal speed. The game will feel like it is in slow-motion because your mind's \"clock\" has been set to a higher speed.\n\nYou get the opposite effect if you do the game in slow motion and then play at normal speed. Suddenly everything is going much faster than you keep up with even though you previously played at that speed just fine.\n\nThe effect wears off after only a few minutes, though. I suspect that something similar is happening to you while you are asleep where your mind is being clocked slower while asleep and still readjusting when you first wake up."
]
}
|
[] |
[] |
[
[]
] |
|
1e0hmf
|
To what extent was Nazi Germany's economic development form 1933 onward "unsustainable"? And what effect did it have, if any, on their decision to go to war when they did?
|
Forgive me, I searched the FAQs and found questions relating to the idea of the German economic miracle in general, but I couldn't find any threads dealing with this specific question. Also, if this is too much of a "what if" type of question, I apologize and can take it to a different subreddit.
I just happened after random Wikipedia browsing to end up reading a lot about the lead-up to WWII, and I'm wondering what the historical consensus is regarding Germany's economic development after the Nazis came into power.
Did their use of the state to basically direct the development of Germany's industries for the purpose of preparing for war have the inadvertent effect of making their economy unstable such that eventually they would have *had* to start a war over economic concerns? I know that Hitler had always had the goal of starting a war of expansion eventually, but is it possible the economic instability forced the regime's hand and made them pursue that war earlier? In the absence of the German initiation of WWII, what would have continued to happen to their economy, given the policies they were pursuing?
I'm not a historian by any means, but I took a bunch of history classes in college, and I recall in a Western Civ course that my professor said that in his opinion, the Nazi economy's outer appearance was a flimsy facade, and that the only way it functioned as long as it did was because the Nazis looted the treasuries of the countries they conquered in order to sustain the homeland's economy a bit longer.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1e0hmf/to_what_extent_was_nazi_germanys_economic/
|
{
"a_id": [
"c9vmtza"
],
"score": [
21
],
"text": [
"Read Adam Tooze's *Wages of Destruction: The Making and Breaking of the Nazi Economy*. It's an excellent overview of all things having to do with the German economy before and during the war.\n\nTooze makes the claim that basically every aspect of German economic policy starting in 1933 was completely unsustainable. In an effort to develop the country's military forces and military infrastructure, Hitler basically sacrificed the entirety of the German economy, especially its hard currency reserves. By 1938, the foreign exchange of Germany was basically nonexistant, and it was fortuitous (or planned) that in the next year and a half, sizable amounts of gold and currency were seized from Austria and Czechoslovakia.\n\nHitler's decision to go to War over Poland was also calculated in large part by the fact that the Nazi economic machine was basically on the brink of burning itself out. It was only by taking the measures that wartime conditions alone could justify, and by (again) seizing much of Poland's wealth, that Germany could ensure it's (still ongoing) military buildup would proceed apace; the trade agreement signed with the USSR also helped matters.\n\nKnowledge of the instability of Germany's economy wasn't a very well-kept secret either; Allied leaders during the winter of 1939-40 believed that Germany's economy would simply collapse on its own accord. Chamberlain famously said that Hitler had \"missed the bus\" by not attacking France after the fall of Poland. Of course, the Western Allies were proven completely wrong when Germany launched its ambitious (mildly crazy) attack through the Sedan to overrun the Allied Armies, but it was a fairly safe assumption that Germany's economy would otherwise have been completely unprepared for the sort of WWI-style attrition battle that everyone was expecting.\n\nIn short, German economic growth between 1933 was completely immaterial. All of the employment gains came at the expense of actual, substantial economy improvements. All of the state's effort and investment was sunk into the improvement of the military machine. Any credit that Hitler gets for saving the German economy, or reducing unemployment, must be tempered by the fact that, had World War II not started when it did, and had Germany not enjoyed such early successes, the economy would have completely collapsed for want of currency. German economic \"growth\", therefore, was indeed completely unsustainable without the sort of plundering of other countries that late 1930s Nazi foreign policy entailed.\n\nSources:\n\n*Wages of Destruction* by Adam Tooze, particularly the first few chapters which detail German economic decision-making during the interwar years, along with the relationship of those economic decisions with German foreign policy, were my primary sources of information for this post. An alternative view, which argues that the German economic recovery was real, can be found in Dan Silverman's *Hitler's Economy*, though this might be difficult to track down outside of the libraries of academic institutions. Personally, I side with Tooze basically 100 percent; I think that the Nazi economic miracle was a bunch of smoke and mirrors."
]
}
|
[] |
[] |
[
[]
] |
|
2bv395
|
A question about the Macedonian Phalanx
|
A writer named Stephen English wrote in his book *The Army of Alexander the Great* that the standard view of a "hammer and anvil" approach in regards to the phalanx holding the enemy in place is wrong, and that the Sarissa phalanx were intended to act offensively, rather than defensively, by attacking the enemy in conjunction with the Companion cavalry. He goes on to say that, once forced to fight defensively, the phalanx would easily be defeated.
What is your view of this?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2bv395/a_question_about_the_macedonian_phalanx/
|
{
"a_id": [
"cj96hhs",
"cj9cwch"
],
"score": [
22,
6
],
"text": [
"I think that any characterization of the phalanx as a defensive formation is wrong. It is clearly a formation designed to overpower an enemy line and force them to rout, which, as I'm sure you know, is where the real victory in a battle comes from (and certainly the **real** defeat). As compared to the light infantry formations they faced, the phalanx was particularly adept at this role, esspecially in terms of line discipline. I would disagree with the assertion that 'when forced to fight defensively' it would be easily defeated. What is his evidence for this assertion? The weakness of the formation was the exposed flanks combined with difficulty in re-positioning, and the strength of the Macedonian flanks (via the cavalry) helped set it apart its Greek peers in that regard, but if any phalanx was forced to fight defensively while it's flanks were collapsing, it of course would be easily defeated. But at that point, the defeat isn't the crumpling of the phalanx, but the crumpling of whatever force was holding the flanks.",
"Phalanx-style tactics were revived in the late medieval / early Renaissance era as a defensive formation against cavalry charges, which probably lends to the misunderstanding of how phalanxes should be used. Late medieval cavalry tactics were very different from ancient Greek cavalry tactics, however. Ancient cavalry were probably dragoons, effectively, as mounted combat in the medieval knightly style was not feasible without the stirrup. Late medieval phalanxes were therefore deployed quite differently from ancient ones.\n\nA medieval knight on a charger was a powerful offensive force, with a long lance, and stirrups and saddles that would keep him from being dismounted after impact. The cavalry charge therefore became the primary medieval shock tactic for shattering the cohesion of the opposing army, allowing them to be pushed off the field. The counter-tactic that eventually became widely adopted [starting around 1300](_URL_0_) was a disciplined heavy infantry with a wall of pikes, which is how phalanx tactics got revived. However, against cavalry this pike wall was very much a defensive formation. If successful, your counter-attack would quite likely be your own cavalry charge against the enemy's pike wall. Repeat back and forth until the disorder of battle caused a break in formation, allowing the cavalry to break though.\n\nIn the ancient world, cavalry did not have this shock power. Instead they were mobile archers and dragoons (mounted infantry) who could (a) rapidly respond to weaknesses in the line or counter-attack in places where the enemy was successfully breaking the line, and (b) pursue a fleeing enemy to prevent them from re-forming.\n\nAncient armies still needed a primary shock force to break the enemy's shield wall and force them off the field, however. Most descriptions of the phalanx have them doing just that, through the [othismos](_URL_1_) - the \"push\", during which huge massed ranks would drive the spears forward into the enemy by sheer force. Whichever side had the weaker push would eventually collapse, and once weakened, became vulnerable to follow-on attacks by auxiliaries and cavalry."
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Pike_%28weapon%29#Medieval_revival",
"http://www.jstor.org/discover/10.2307/1192506?uid=3739400&uid=2129&uid=2&uid=70&uid=3737720&uid=4&sid=21104010132991"
]
] |
|
5e8hm4
|
Was the 94% marginal tax rate under FDR effective in its goal? Or did the wealthy simply wriggle through the loopholes?
|
You hear about the prosperity under high taxes, but were these taxes actually bringing in more money % gdp relative to today? Sorry, I am a high school student who dosen't have a complete grasp.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/5e8hm4/was_the_94_marginal_tax_rate_under_fdr_effective/
|
{
"a_id": [
"daakc61",
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358,
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"text": [
"Given the economic boom across the 1950s, I'd like to ask the same question about Eisenhower (91% top rate) ",
"You can see a graph of federal tax revenues as a share of GDP at [FRED](_URL_0_). The data points you're looking for are that when the top marginal rate went up, taxes as a share of GDP rose from 3.23% to 7.72%, so yes, tax revenue went up.\n\nBy the end of WWII, total revenue had risen to 19.79%, and it has fluctuated between that number and 14.45% ever since.",
"My understanding is that there were many more deductions and loopholes available then so that no one actually paid the 90%+ tax rate. This was discussed in this previous post;\n\n_URL_1_\n\nAnd in this article it references:\n\n_URL_0_",
"The [Tax Policy Center](_URL_0_) publishes figures on taxes relative to GDP from 1934 to 2020 (estimates into the future). Income taxes tend to be volatile, particularly on the richest, but they were about 1% of GDP in the 1930s, 7% of total GDP in the 1950s, and about 7% so far in the 2010s (actual data, that is, leaving aside the projections).\n\nSo the answer to your question looks like no, the 94% rate didn't actually bring in more revenue as a share of GDP than the current system. \n\nNote: how much of this is wriggling through loopholes versus how much it is due to explicit design making for much lower taxes on the rest of the population is beyond me. Particularly if we don't have a strict definition of loopholes. "
]
}
|
[] |
[] |
[
[],
[
"https://fred.stlouisfed.org/series/FYFRGDA188S"
],
[
"http://www.taxhistory.org/thp/readings.nsf/ArtWeb/AEEC9CAC8F773DD7852579C20073FD36?OpenDocument",
"https://m.reddit.com/r/AskHistorians/comments/3sure6/people_keep_saying_that_the_income_tax_rate_under/?ref=search_posts"
],
[
"http://www.taxpolicycenter.org/statistics/source-revenue-share-gdp"
]
] |
|
7q0t49
|
Has any person or group been successful in making (large scale) alterations to a language?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7q0t49/has_any_person_or_group_been_successful_in_making/
|
{
"a_id": [
"dsli9c1"
],
"score": [
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],
"text": [
"Sorry, we don't allow [\"example seeking\" questions](_URL_0_). It's not that your question was bad; it's that these kinds of questions tend to produce threads that are collections of disjointed, partial, inadequate responses. If you have a question about a specific historical event, period, or person, feel free to rewrite your question and submit it again. If you don't want to rewrite it, you might try submitting it to /r/history, /r/askhistory, or /r/tellmeafact. \n\nFor further explanation of the rule, feel free to consult [this META thread](_URL_1_)."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/wiki/rules#wiki_no_.22example_seeking.22_questions",
"https://www.reddit.com/r/AskHistorians/comments/3nub87/rules_change_throughout_history_rule_is_replaced/"
]
] |
||
2r69mf
|
Is it possible that there are distant stars moving away from Earth so fast that light from them would never reach the Earth?
|
I suppose there are two parts to the question. The first is whether an object can have a relative velocity greater than the speed of light (taking into account the expansion of the universe). The second follows from the first and I'd particularly like to know the application of special relativity to that scenario.
|
askscience
|
http://www.reddit.com/r/askscience/comments/2r69mf/is_it_possible_that_there_are_distant_stars/
|
{
"a_id": [
"cnd0vqf",
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],
"score": [
26,
2
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"text": [
"Hi /u/nemodatass,\n\n > The first is whether an object can have a relative velocity greater than the speed of light (taking into account the expansion of the universe).\n\nIf we consider the instantaneous rate of change in distance of the Milky Way relative to an object at a redshift z~2 (a comoving distance of ~17 billion light-years), the [recessional velocity](_URL_4_) is approximately c. The recessional speed will exceed c at greater comoving distances.`[; \\dag ;]` To be clear: we can see objects at these (and greater) distances, but the light many of them are emitting *now* will never reach us because this light will never overcome the metric expansion of the universe. The light we see from them was emitted at a time when that light could overcome the metric expansion of the universe, but many of those objects are now beyond the region where they can emit light that we will receive.\n\n(It's actually a little more complicated. Objects outside the surface defining the Hubble volume can actually pass into \"causal contact\" because the evolution of the surface of the Hubble volume is complicated. What we should really talk about is the cosmological event horizon, but that's a lot of detail that I don't want to bring up for the sake of brevity. But there is a surface -- surprisingly corresponding to objects that have a recessional velocity which is actually greater than c -- which defines all the objects we can receive light from which is emitted now. That surface is the cosmological horizon.)\n\nNow, it can be misleading to think of this speed as an ordinary speed you might measure in an inertial reference frame. This is important, and it leads into your next question.\n\n > The second follows from the first and I'd particularly like to know the application of special relativity to that scenario.\n\nThe special theory of relativity doesn't apply to this scenario because the special theory of relativity is formulated within a spacetime that does not describe the global curvature and geometric features of our universe. The special theory of relativity is formulated using [Minkowski spacetime](_URL_0_). The Minkowski spacetime has no curvature, i.e. it's flat. Our universe's global curvature and geometric features are described by the [FLRW spacetime](_URL_1_). The FLRW spacetime *does* have curvature.\n\nIt is true that locally, no observer will see an object exceeding the speed of light in an FLRW universe. In technical language, this is because [metrics](_URL_5_) of [Lorentzian signature](_URL_2_) will locally look like Minkowski spacetime. In much the same way that a sphere such as the Earth locally looks flat but possesses global curvature, the universe might locally look like Minkowski spacetime but globally be described by the FLRW spacetime. Since the global behavior of an FLRW metric is not Minkowskian, the long distance features do not fall into the realm of the special theory of relativity. \n\nA possibly helpful illustration is the following: We are discussing making global measurements of velocities, but the question is posed in such a way that we are imagining the universe to be described by Minkowski spacetime since we know the special theory of relativity is true (at least within the domain that it applies). This is *identical* to trying to compute the distances between points on a sphere separated by a path constrained to the surface of the sphere *with the assumption that the sphere is flat*. Does a sphere locally look flat? Yes, and you know this because you live on a sphere that locally looks flat. But we cannot assume that the formula we use to obtain distances on flat surfaces will apply to distances on surfaces which are curved. We cannot assume that the global geometry of the sphere is identical to its local geometry. This assumption will give you the incorrect distance. \n\nNow, would you throw your hands in the air and say that distances on a sphere don't properly add up, so Euclidean geometry must be all wrong? No. It's just that you're assuming some incorrect things about the geometry of your object. In the same way, obtaining recessional velocities greater than c is fine since this is a manifestation of the global geometry of a spacetime which is not Minkowskian. While the special theory of relativity may not describe these physics, it's fine because it's not supposed to describe these physics anyhow!\n\nIf you're interested in deeper discussions and interesting plots, try looking at [this paper](_URL_6_). It's a well known paper because it attempts to refute many misconceptions that even physicists have about the metric expansion of the universe.\n\nHope this helps!\n\n`[; \\dag ;]` If you're uncertain about what is meant by [\"comoving distance,\"](_URL_3_) don't worry. It's an alternative way to describe the distance to objects in the universe.",
"for a more simple answer:\n\n1. yes, it can have a relative velocity, faster than the speed of light. the observable universe is the border.\n\n2. special relativity doesnt apply here, the space itsself is stretching, and no mass is accelerated for this process."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Minkowski_space",
"http://en.wikipedia.org/wiki/Friedmann%E2%80%93Lema%C3%AEtre%E2%80%93Robertson%E2%80%93Walker_metric",
"http://en.wikipedia.org/wiki/Metric_signature",
"http://en.wikipedia.org/wiki/Comoving_distance",
"http://en.wikipedia.org/wiki/Recessional_velocity",
"http://en.wikipedia.org/wiki/Metric_tensor",
"http://arxiv.org/pdf/astro-ph/0310808v2.pdf"
],
[]
] |
|
4n12fc
|
why does a bicycle get more stable when you move ?
|
I think most of us who have ridden a bicycle can say that they cannot keep the bicycle upright without their feet touching the ground while it's stationary, but once you start accelerating, you feel the bicycle becomes much more stable. *So can someone explain why there is a directly proportional relation between speed and and stability ?*
**Edit 1 : Can someone give an in-depth explanation as to why this happens ?**
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4n12fc/eli5_why_does_a_bicycle_get_more_stable_when_you/
|
{
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"d3zwtvn",
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3
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"text": [
"It's sort of a combination of momentum and centripetal force. The faster the wheels turn, the more force is exerted towards the outside of the tire, making it \"want\" to continue its path. Also the momentum of the actual bike. Momentum is easier to change in direction at a slower speed. Once up to speed, it likes going the direction it already is.",
"There are a number of factors at play, both relating to the bicycle, and the person riding it. \n\nCoincidentally, before I came across this post, I saw a video in which James May explains it all really nicely: _URL_0_"
]
}
|
[] |
[] |
[
[],
[
"https://www.youtube.com/watch?v=nhMECbDRVLI"
]
] |
|
affnw6
|
why does the human brain like patterns so much?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/affnw6/eli5_why_does_the_human_brain_like_patterns_so/
|
{
"a_id": [
"edy8y80",
"edynqd1"
],
"score": [
9,
3
],
"text": [
"When real patterns are detected, like cause & effect, they frequently offer the ability to predict likely or logical outcomes of actions or events, and that offers survival value. ",
"Because whole nature functions in patterns. Imagine that the Sun doesn't rise every day, and that there isn't a pattern of seasons every year. How would people predict when to plant seeds, or when to collect goods for winter? Or even \"worse\", imagine that everything that happens, happens that time only and never repeats."
]
}
|
[] |
[] |
[
[],
[]
] |
||
10bpfa
|
what is to sing in tune.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/10bpfa/eli5_what_is_to_sing_in_tune/
|
{
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"text": [
"You mean...what it is to sing in tune? As in, what it feels like/means to sing a song with the right pitch?",
"In a song, each sound is supposed to be at a certain pitch. If the pitches are right then one is singing in tune. If any of the pitches are sung too high or too low then one is singing out of tune.",
"To sing \"in tune\" with someone else means to sing in \"harmony\" with them. Or to sing \"in tune\" by yourself, means to sing in harmony with your *previous notes*. \n\nWhen two notes are \"in tune\" or \"in harmony\", then they sound good together or good following each other. Most people can *feel* this automatically, because it sounds \"good\".\n\nA \"note\" is a sound made when something vibrates at a fixed rate, for example, 256 vibrations per second (or 300, or 378, or whatever). If the rate increase, the note goes up in sound, higher and higher in \"pitch\". 800 is a really high note, it vibrates really fast! If the rate decrease, the note goes lower and lower in \"pitch\". 100 is a really low note, it vibrates real slow. \n\nThe \"something\" that vibrates can be any object - your voice-box, a guitar string, a wine glass - if they vibrate the same number of times per second, they have the same \"pitch\". \n\nSo what makes two notes \"in tune\"?\n\n**The number of times the *second* note vibrates needs to be a simple ratio of the number of times the *first* note vibrates.** \n\nThe simplest way 2 notes are \"in tune\" is if they vibrate the same number of times per second, at 1 to 1, or 1:1.\n\nThe next simplest way is if the second note vibrates exactly twice as fast, or twice as slow. For example: a 200 note and a 400 note sound good! It's a simple ratio, or a simple *multiple*. A \"doubling\" of the number of vibrations is the most perfect and beautiful 2 notes that are \"in tune\" - it's called an **octave**. If your two notes vibrate 250 and 500 times per second, that's just as good, that's also an octave.\n\nA 200 note and a 300 note is also beautifully \"in tune\". For every 2 vibrations of the first note, the second note vibrates 3 times! A perfect \"ratio\" of 2:3. \n\n3:4 is also good. But 11:13 and 71:89 probably sound really ugly!\n",
"The human voice isn't like a piano, where you can press a key, and it'll be the note you want (assuming it's been tuned properly). We can slide our voices up and down with a lot of variation. This means that it's possible for us to sing SLIGHTLY lower the note we want (singing flat) or slightly higher (sharp). Singing in tune means singing exactly - or as close as possible to - the note we want without sliding above or below it.\n\nThe reason you don't want to sing OUT of tune is because that slight dissonance makes a natural \"clashy\" sound, and breaks the continuity of the song. Walk up to a piano, find a white key and a black key that are right next to each other, and play them both at once. Nasty sounding, ain't it? Now imagine two singers trying to sing the white note, but one of them sings the black one by mistake. That would be singing \"out of tune\".\n\nYou want to sing in tune so that all the notes fit nicely with the music and with each other without clashing.\n\nHopefully that helps :)"
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
26biz1
|
Did the Romans only use people who'd been slaves their entire lives as house servants? If "no" how did they keep freshly captured barbarians with nothing to loose from killing their masters?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/26biz1/did_the_romans_only_use_people_whod_been_slaves/
|
{
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"text": [
"If i remember correctly they took very few adult male slaves for just that reason. Women and children were mainly the ones that were captured and sold. The male slaves would then have lived their whole life or most of it in slavery. The Romans would also separate boy slaves from their fathers so they would grow up weak. "
]
}
|
[] |
[] |
[
[]
] |
||
4pnsc1
|
will we ever have designer babies? are there laws now that prevent this?
|
I don't want to leave my offspring's genes up for chance and I would love to know what the status is and if there are laws preventing genetic modification.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4pnsc1/eli5_will_we_ever_have_designer_babies_are_there/
|
{
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"d4mf3eg",
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"score": [
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],
"text": [
"The issue at hand isn't legal (yet anyway)... but rather technological and cost based.\n\nWe're getting close to a Gattica scenario... but we're not there yet.",
"There are in the UK, and in many other countries. The [Human Fertilisation and Embryology Authority](_URL_0_) is the regulator here. "
]
}
|
[] |
[] |
[
[],
[
"http://www.hfea.gov.uk/"
]
] |
|
b9ddt6
|
Is it possible to predict the next major mountain range?
|
Since we as humans are aware of the shifting and colliding of the tectonic plates to create mountains, are we also capable of predicting when and where the next fresh mountain range will appear? Also, about how long does it take for (just as an easy example) totally flat ground to become a mountain range like the Rockies or the Himalayas?
|
askscience
|
https://www.reddit.com/r/askscience/comments/b9ddt6/is_it_possible_to_predict_the_next_major_mountain/
|
{
"a_id": [
"ek9awnf"
],
"score": [
2
],
"text": [
"Yes and no. You are correct that we con forward model the movement of plates to a certain extent (such predictions exist) so we can anticipate the location of collisional plate boundaries that favor the formation of mountain ranges. But the formation of mountain ranges also depends on rates of erosion that depend on climate, and I don't think anyone can predict climate over geological timescales. "
]
}
|
[] |
[] |
[
[]
] |
|
5p69qg
|
can a bullet be reused at all? if not, why not? thanks
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5p69qg/eli5_can_a_bullet_be_reused_at_all_if_not_why_not/
|
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"text": [
"Yeah but not immediately. Especially if it hits something, when they hit something they usually get deformed. But bullets can be like melted down so it can be reused ",
"In the short term no. The bullet would have to be put in a new casing with powder and a primer, but if you mean taking the bullet, melting it down, then reforming a new bullet inside a cartridge then yea.",
"The bullet itself can be melted down and reformed into a bullet again. The shells are commonly reused, I used to collect them at the rifle range for my grandfather. The gunpowder is spent though.",
"Reloader here.\n\n4 parts to a cartridge:\n\nBullet (projectile)\n\nCase\n\nPowder\n\nPrimer\n\nPowder and primer are spent. The cases, yes absolutely can be de-primed, cleaned, and reused. The projectiles are a bit trickier. If it's just lead then you can recast it. If it's jacketed you can still melt it down, but then you have to separate out the copper from the lead. \n\nMost reloaders collect and re-use cases. I've never seen one who collects the projectiles.",
"If a bullet hits something solid it is normally deformed beyond the point of reusability. However you can just recast the lead and copper into new bullets. Bullets are designed to be expendable and cheap so it's not usually desirable to try and reuse them.\n\nBullet casings, which are normally ejected from the gun when fired can usually be reused, however. They may require trimming or other adjustments because they are often deformed when fired. The primer and powder must be replaced and a new bullet must be fitted. This is called handloading or reloading."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
||
go7j1
|
Does your blood type affect your health in any way (except in the case of transfusions and transplants)
|
For instance, gives you a resistance to certain diseases? Certain drugs are more or less effective? Anything else? (I know those with sickle cell anemia are more resistant to malaria, but it's not a blood type and it's a disease in itself)
|
askscience
|
http://www.reddit.com/r/askscience/comments/go7j1/does_your_blood_type_affect_your_health_in_any/
|
{
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44
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"text": [
"There may be some relationship between A-antigens and influenza, B-antigens and gram-negative bacteria. [Wiki: ABO blood group system](_URL_0_)",
"Yes, there have been many diseases linked to differing outcomes based on your classic ABO blood type. Here are a few examples.\n\n*Helicobacter pylori* establishment in patients with pancreatic cancer is greater for those with non-O blood type. [National Cancer Institute, 2009](_URL_1_)\n\nNoroviruses use ABO antigens to attach to red cells in order to infect the cells. O group antigens are more susceptible to attachment and subsequent infection. [Journal of Infectious Diseases, 2002](_URL_0_)\n\nThe Vibrios also show different affinities for ABO types. O groups are much more susceptible to severe *V. cholera* infection but not the other vibrios such as parahemolyticus. [Infection and Immunity, 2005](_URL_2_)\n\n*E. coli 0157* also shows higher rates of infection in O groups. Normalized for infection rate O groups show a higher susceptibility to developing hemolytic uremic syndrome with this infection than other blood types. [Journal of Infectious Diseases, 2002](_URL_3_)\n\nHere is a decent though far out of date review over ABO type and disease susceptibility. [Clin Micro and Infectious Diseases](_URL_4_)\n"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/ABO_blood_group_system#Origin_theories"
],
[
"http://jid.oxfordjournals.org/content/185/9/1335.short",
"http://jnci.oxfordjournals.org/content/102/7/502.short",
"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1273892/",
"http://www.jstor.org/pss/30137589",
"http://www.springerlink.com/content/kg80125321n53037/"
]
] |
|
f6xve0
|
Why are cases of dementia more common in North America and Europe compared to the rest of the world?
|
askscience
|
https://www.reddit.com/r/askscience/comments/f6xve0/why_are_cases_of_dementia_more_common_in_north/
|
{
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"fi95da4",
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15
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"text": [
"People live longer in developed countries compared to developing countries. They are also more likely to see a doctor on a regular basis which would allow them to diagnose such a thing. So the actual incidence may not be too different, just documented more.\n\nA possible cause could be related to diet and life style. Dementia and Alzheimer's are diseases of inflammation, so things that cause inflammation may be more prevelant in America and Europe",
"Reliable information is probably harder to get from poorer countries especially for mental illnesses which carry a bit more stigma than most. Reporting, diagnosis and treatment being more available in wealthier countries. \n\nIt is probably hard to make the conclusion you state in the title."
]
}
|
[] |
[] |
[
[],
[]
] |
||
4tie4h
|
how does vacuum insulation (like in a thermos) work? why is it so good at keeping things hot or cold?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4tie4h/eli5_how_does_vacuum_insulation_like_in_a_thermos/
|
{
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"text": [
"Heat travels in three ways, convection, conduction, and radiation. \nConvection is from an air or fluid flowing over the object. Example: the steam coming off tea, or when you open a hot oven and feel a blast of heat on your face. \nConduction is from the two objects (one hot and one cold) physically touching each other to transfer heat. Example, how an egg cooks when it hits a hot griddle, or how you burn your hand on the stove. \nRadiation is from energy carrying particles hitting the object. This can travel through a vacuum and is how the sun heats the earth. \nBy putting a hot or cold liquid in a thermos, you are preventing two of the three methods of heat transfer. You prevent convection because it's sealed so no flowing air goes over it, and Conduction because there is no matter in a vacuum, meaning there nothing touching so the heat can't transfer on touching things. Plus most radiation is blocked by the thermos not being clear (most common form of radiation heating is light). So you are slowing down heat transfer like how shutting down lanes of a road slows traffic. ",
"Heat always transfers from hot to cold. If one atom touches another atom, the hotter one transfers its heat to the colder one until they are the same. If Atom A is 100 heat and Atom B is 50 heat, if they stay together they will both end up at 75 heat. Vacuums are a space without matter, they are literally empty. If Atom A is on one side of the vacuum (inside a thermos) and Atom B is on the other side (outside thermos), then they can't touch each other, and can't transfer heat. ",
"For moderate temperature differences (i.e., those between the temperature of the liquid in your thermos and temperature of the environment outside your thermos), heat exchange occurs primarily through direct physical contact between solid, liquid, and/or gaseous materials. In the vacuum between the walls of the inner and outer containers that constitute your thermos, almost all matter (including the air) has been removed. If there is no medium through which heat can travel, insulation will be excellent!"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
1pkgxd
|
why is debating another person so appealing?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1pkgxd/eli5_why_is_debating_another_person_so_appealing/
|
{
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"cd37vg0",
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"text": [
"Who said it was appealing?",
"Debating forces you to examine your own thoughts more closely. It challenges your mind. It's like sports, only better because it's your brain, not your muscle that wins or loses."
]
}
|
[] |
[] |
[
[],
[]
] |
||
3mby68
|
how do telescopes work?
|
I know they use mirrors but how can a telescope clearly see in space?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3mby68/eli5_how_do_telescopes_work/
|
{
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"text": [
"You stack a whole bunch of hobby lobby microscopes and shove them in a paper towel tube. Wait til it's night time, point it at the sky and enjoy.\n\nMore info at /r/telescopes ",
"How can they see clearly in space? Because of the lack of an atmosphere. An atmosphere causes all sorts of disturbances. By putting the telescope in space you take away one of the things that not only blocks light but also bends it. This allows you to not only see further and see dimmer objects but allows you to see them more clearly.",
"For the kind of scope that use mirrors, think of them as light buckets. Now think about it raining in an ordinary bucket, the larger the diameter the bucket, the more rain enters the bucket at any given time. If you have a cup and bucket next to each other out in the rain for one hour, the cup will collect (for example) 10 drops of rain per minute while the bucket will collect 100 drops per minute. \n\nGo back to our light bucket, photons from space are \"raining\" down all the time, the bigger the scope, the more light it collects, this light is then focused (because the primary mirror is curved) onto a secondary mirror that directs it into an eyepiece. The eyepieces are just glass lenses that magnify that focused light in to your eye. \n\nUnfortunately, our eyes (and brain) don't have very good resolution. To comprehend this, stare at your wall from 10 or 15 feet away, typically you won't see the texture of the paint, move closer and closer and texture starts to appear. \n\nThis same principle applies to telescopes when matched to our eyes. When viewing objects through a scope, we typically see very little color. The planets are close enough that we see some color, buts it's much more faded than you see in pictures. This is because cameras can hold the lens open longer and actually collect the light. Our eyes and brain capture some light then it goes away, but over time even the brain retains some of that light and the more you view objects over time, the more the minds eye reveals. \n\nSource: Amateur Astronomer with 16\" diameter scope. \n\nEdit because I was on break... The reason we can sometimes see clearly into space has to do with the atmosphere and the amount of humidity and pollution in the air. For instance when I look at the moon, I can see craters clear as day if magnification (eyepiece size) is low, but the more I magnify, I also magnify the atmosphere between me and the moon and often the moon looks like it's in water (like when your driving on a hot day and you see the road kind of shimmering). Heat in the atmosphere can add to the shimmering. Telescopes on top of mountains are less susceptible to this effect because it's cold up there, but they can suffer from humidity if it reaches up that high. \n\nTl:dr, the bigger the mirror, the more light it catches/reflects, faint objects in a smaller scope won't be as bright or detailed. ",
"You have lenses in the tube that enhance the image. Essentially, the lenses \"gather\" light at a certain point on a mirror, then that image is reflected into your eye. The \"gathering\" of light gives the illusion the image is much closer than it is.",
"Short answer - they work the same way a magnifying glass or your glasses work. Just more lenses and or mirrors. They are a different focal length magnifying glass that we point at more distant objects, that's all. "
]
}
|
[] |
[] |
[
[],
[],
[],
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|
252jst
|
Why are some mushrooms and fungi flammable?
|
A lot of mushrooms are used as tinder by outdoorsmen, such as [amadou](_URL_0_) which comes from [horse hoof fungus](_URL_1_).
Why are mushrooms more flammable than other plants?
|
askscience
|
http://www.reddit.com/r/askscience/comments/252jst/why_are_some_mushrooms_and_fungi_flammable/
|
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"text": [
"Because they contain a large amount of combustible material and not much water.\n\nThe reason most plant material (I know fungi aren't actually plants) does not burn easily is because it contains a large amount of water. For any substance to burn you need three things:\n\n* Fuel\n* Oxygen\n* High temperature\n\nWhile there is a lot of water in the material, the temperature is held down to around 100C by the water. You need to boil or evaporate that water before the temperature of the material can rise high enough for the oxygen to bind chemically with the fuel material.\n\nSome plants have a low enough water content that they burn readily. Examples are some fungus fruiting bodies, pine needles and eucalyptus leaves.\n"
]
}
|
[] |
[
"http://en.wikipedia.org/wiki/Amadou",
"http://en.wikipedia.org/wiki/Fomes_fomentarius"
] |
[
[]
] |
|
jo4d6
|
what is model/view/controller?
|
I'm learning python and using the web framework Django. I've set up simple sites but I still don't totally understand the MVC...thing. I've read wikipedia but I guess I don't really get it.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/jo4d6/eli5_what_is_modelviewcontroller/
|
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"Model holds the data, view shows it to the user, controller takes input and tells the model how to update the data.\n\nIf reddit is an MVC design (dunno if it is), then the database of links and comments is the model, HTML and CSS make the view, and the scripts that run when you click a button are the controller.",
"Model holds the data, view shows it to the user, controller takes input and tells the model how to update the data.\n\nIf reddit is an MVC design (dunno if it is), then the database of links and comments is the model, HTML and CSS make the view, and the scripts that run when you click a button are the controller."
]
}
|
[] |
[] |
[
[],
[]
] |
|
5vr6br
|
what's the difference between chicken nuggets and boneless chicken wings?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5vr6br/eli5_whats_the_difference_between_chicken_nuggets/
|
{
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"text": [
"Chicken nuggets are chicken meat that has been ground up and turned into little dinosaur-shaped reconstituted chicken food products coated in breading.\n\nBoneless chicken wings are pieces of chicken breast coated in breading."
]
}
|
[] |
[] |
[
[]
] |
||
aqacrt
|
Is a study with a small sample size less meaningful than one with a big sample size?
|
To my understanding, the p value of a study determines how likely a result this extreme or more extreme would happen if there were no effect (e.g. due to coincidence, measuring inaccuracies etc.).
Thus, if you have two studys, one with a small sample size (let's say 10 persons) and one with a big sample size (let's say 1000 persons), which both have an identical p value, they should be equally reliable.
However, people commonly criticise studies for having small sample sizes. Does the small sample size actually affect how meaningful a study is?
I know that their power would be different, but if they both identified an effect with a p-value of less than 0.05, shouldn't they be equally reliable?
|
askscience
|
https://www.reddit.com/r/askscience/comments/aqacrt/is_a_study_with_a_small_sample_size_less/
|
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"Your definition of a P value is better than most scientists could give!\n\nHowever, your next statement is not exactly correct, at least in my opinion (though very understandable). In fact, you could probably ask 10 statisticians this question and get 10 different answers.\n\nThe clearest, and least controversial case where the same P value should lead to different conclusions is when you are *not* rejecting the null hypothesis, that is, you are saying that there is no effect. Small sample sizes make it very likely to get large P values. Indeed, generally speaking, as the sample size approaches zero, the distribution of P values becomes flat (i.e. getting the probability of getting p < 0.05 is about the same as getting p > 0.95), even if there is an effect. However, as the sample size increases, when there is an effect, the distribution of P values you could get becomes very left skewed, and when there is no effect, the distribution is flat. What this means is that with small sample sizes, even if there is an effect, your P value is very likely to be greater than 0.05. While with large sample sizes, if there is an effect, P values are very unlikely to be greater than 0.05. So, a small study, that says P > 0.05 doesn't really have much use.\n\nTo the skewing of the distribution of P values means that that as the sample size (n) approaches infinity, if the null hypothesis is incorrect (i.e. there is an effect) then P should approach zero. This leads to an almost paradoxical case that if your study is well powered, then a P value that would classically be considered an indicator of a significant result (e.g. 0.04) is actually an indication that the null hypothesis is true (i.e. there is no effect). This is because if there is an effect, P should be basically equal to zero, and so the fact that it is so comparatively large tells you something is up. Hence, this shows us that a P value of 0.04 can suggest different things depending on whether your sample size is 10 and your sample size is 10 thousand.\n\nThere are other caveats when looking at P values. One is about the prior likelihood. For instance, if a result is unlikely, then a P value only marginally less than 0.05 shouldn't be seen as very good evidence to reject the null hypothesis. But the important thing to think about is \"what effect size are we looking for?\" P values, effect sizes and sample sizes form a triangle that need to be considered together. If the effect we expect is large, and our P value is small, then a small sample size is reasonable to use. If our effect size is small, but our P value is very very small, if we generated that with a a small sample size, then that is probably acceptable. However, a small effect size, a big p value and a small sample size is meaningless.\n\n",
"All other things being equal, larger sample sizes lend greater credibility to a result. In mathematical terms, larger sample sizes tend to produce smaller p-values if all other things are equal. This is basically the [Central Limit Theorem](_URL_0_) at work.\n\nPractically speaking, all other things are not equal. Effect size will also affect the computed p-value for a statistical test. The design of the study is also important. Sampling bias, experimental bias, etc. can render an otherwise-larger study with more significant p-values less meaningful.",
" > . Does the small sample size actually affect how meaningful a study is?\n\nYes, depending on what you mean by meaningful. \n\nHaving the same probability of a type I error doesn't imply that they have the same probability of a type II error.\n\n > which both have an identical p value, they should be equally reliable.\n\nThis is a mistaken understanding. P-values are random quantities; if the null is true (and the statistic is continuous) then the p-value has a uniform distribution, it could be anywhere. If the null is false, the p-value could still be anywhere but skews much more toward 0 (and more strongly with increasing sample size).\n\nYou can get low p-values by chance either way (or, indeed, high ones, if more rarely with a false null).\n\n*Ceteris paribus*, if you get a low p-value and a true null is a real possibility, then when you have a low-powered study you may need to retain a strong suspicion that a low p-value may just be due to random variation rather than a true effect (more so than if the sample size were larger). \n\nThe quantity of interest would be P(Ho false | rejection) (how 'reliable' the rejection was)\n\nThis is higher when the power is higher (at a given specific alternative)\n\n",
"Not sure if this meets what you think of as reliable, but: the same p-value *does* mean the same thing at different sample sizes IF there is no effect. This is because, by design, p-values will be uniformly distributed under the null. So it controls the false positive rate regardless of sample size—if you use a threshold of .05 and the null hypothesis is true, you will reject it 5% of the time *at any sample size.*\n\nHowever this isn't always what people want to know. As others have pointed out, sample size affects the statistical power, or true positive rate. Combined with the fact above, that the false positive rate is constant, we see that a larger sample size will yield (across tests of different hypotheses) more true positives and the same number of false positives. Therefore, a greater proportion of your positives will be true positives. Conversely, with smaller sample sizes, more of your positives will be false positives (than with larger sample sizes). This is the [false discovery rate](_URL_0_).\n\nA good paper on this: Button, K. S., Ioannidis, J. P., Mokrysz, C., Nosek, B. A., Flint, J., Robinson, E. S., & Munafò, M. R. (2013). Power failure: why small sample size undermines the reliability of neuroscience. Nature Reviews Neuroscience, 14(5), 365. [(pdf)](_URL_1_)"
]
}
|
[] |
[] |
[
[],
[
"https://en.wikipedia.org/wiki/Central_limit_theorem"
],
[],
[
"https://en.wikipedia.org/wiki/False_discovery_rate",
"https://swiss3rnetwork.org/wp-content/uploads/2013/12/powerfailurenrn3475.pdf"
]
] |
|
47aoro
|
Why is is the i root of i^i not i ?
|
askscience
|
https://www.reddit.com/r/askscience/comments/47aoro/why_is_is_the_i_root_of_ii_not_i/
|
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"The ith root of i^i is i. It is not the only root because the root function is multivalued over the complex numbers. If you are taking natural number roots, specifically the nth root you would have exactly n solutions. For general complex numbers you may actually have infinitely many solutions (as is the case here), but the obvious solution works."
]
}
|
[] |
[] |
[
[]
] |
||
1n68af
|
why is flexibility attractive in women?
|
In response to [this](_URL_0_) post, where the top comment regards it as attractive.
Lots of guys seem to find flexibility incredibly arousing, but it I don't find any appeal in it. Some sources claim that it has to do with being able to use more positions in bed, but that seems like too minor a detail to make a difference. Am I mistaken?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1n68af/eli5_why_is_flexibility_attractive_in_women/
|
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"nope its all about the sex, for me its just the idea of what it means is on the table for us to be able to do. I may be able to try new positions with a more flexible partner. Is it a huge deal? no, but its enough to get a few thoughts rushing through my head. ",
"It may have something to do with being an indicator as to the natural fitness of the woman. This means that they are more likely to produce a healthy, strong, fit baby. Hence the male attraction to this characteristic.\n\nAnother example of this is mens infatuation with large breasts. Large breasts means greater supply of nourishment for the baby. Which means the baby is more likely to survive infancy.\n\nOr how men check out women's rears. What men are really looking at is the width of the hips which is important to the safe birthing of a child.\n\n\nNearly everything a man finds physically attractive in a woman has something to do with their ability to reproduce or the strength of the genes they might provide. It's classic Darwinian evolution.\n\nHow the modern media has distorted this view by using skinny, flat models is a psychological discussion for another day."
]
}
|
[] |
[
"http://www.reddit.com/r/gifs/comments/1n4ywn/her_legs_just_keep_spreading_it_hurts_to_watch/"
] |
[
[],
[]
] |
|
1jq3d3
|
night vision and shadows?
|
Why does night vision on cameras and stuff show shadows behind what they're filming? Hope this makes sense!
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1jq3d3/eli5_night_vision_and_shadows/
|
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"Night vision amplifies available light. A faint source of light that you can't see still casts a shadow, you just can't make out the difference. Night vision can.",
"The nightvision cameras use a light to illuminate the subjects. The trick is that the light shines infrared light, not visible light. The camera, unlike our eyes, can actually see this infrared light. The reason we see a shadow is that the infrared light is not perfectly aligned with the camera's lens (how could it be! If it were, it would get in the way of the picture). Since the light is, for example, just slightly higher and to the right of the lens, we see shadows in the image which are slightly low and to the left.\n\nThink about when you see a [picture with flash](_URL_0_). The shadows are there for the same reason; the flash bulb, which in this case emits visible light, is in a slightly different location compared to the lens.",
"If I understand your question correctly, basically you're asking why you see shadows with night-vision enabled cameras as you would with a normal camera that had a regular light on it?\n\nThe answer is that night-vision enabled cameras use infrared light for filming. Our eyes cannot see infrared light, but certain camera equipment can. Night-vision enabled cameras basically have an Infrared (IR) flash-light on them that is basically invisible to the naked eye but floods the area with IR light just as a normal flash-light would do with visible light. The IR light casts shadows just like how regular visible light would. \n\nThe camera then simply translates the infrared light information into frequencies in the visible portion of the electromagnetic (light) spectrum that we can see. One problem with using the Infrared portion of the spectrum for recording video is that there are no colors associated with Infrared light, so when its translated to visible light we only get one color (e.g. everything looks green).\n\nNote that there are also night-vision cameras which employ a different method of filming. These are passive heat-sensitive cameras that basically detect natural infrared light being emitted in the environment and translate it to visible light for us to see. In case you are unaware, everything that's warm glows with infrared light naturally. If humans could see Infrared light, we would literally see each-other glowing in the dark. So these types of night-vision cameras are used for checking thermal temperatures and for tracking people/animals at night. The problem with these types of cameras is they have very poor resolution in the sense is that all you see is a glowing blob and not any substantial detail whereas the night-vision mode commonly found on regular cameras (described earlier) supports full HD resoultion and detail."
]
}
|
[] |
[] |
[
[],
[
"http://www.wired.com/images_blogs/underwire/2013/01/mf_ddp_large.jpg"
],
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|
2gv5gs
|
why is there no *grass roots* movement against saudi arabia like there was outrage over apartheid?
|
It seems that their treatment of women is worse than apartheid, not to mention the execution of "sorcerers."
My first thought is "because oil" but the anti-apartheid movement began with students.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2gv5gs/eli5_why_is_there_no_grass_roots_movement_against/
|
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"Because when it comes to the Middle East, all of their protesting is reserved for Israel.\n\nETA: Holy cow, gold! My first gold! Thank you, kind Redditor!",
"Causing instability in an oil-rich country? CIA doesn't like that.",
"The right is against Islam, so you have to be reactionary and support it as a result. It's really backwards since the places that actually need feminism are ignored by feminists and given a free pass",
"TL;DR Saudi Arabia has a lot of money that they use to swiftly squash all dissidents.\n\nBecause of their oil, Saudi Arabia has resources beyond our comprehension. One thing they direct those resources towards is security--specifically internal security. There are definitely dissidents in Saudi Arabia. But they typically (always?) get silenced before they can rouse any detectable rabble. I think we can use our imagination to define 'silence' in this case. My educated guess would be that Saudi Arabia has communication monitoring systems similar to what our NSA has been recently revealed to possess. Their monitoring system could even be built using technology borrowed from us, under the notion that monitoring bad guys in Saudi Arabia benefits the US war on terror (and purchased from the US in exchange for large amounts of cash, intel or security favors). So now armed with cutting edge monitoring technology and their vast resources, they can sweep up dissidents as fast as dissidents can pop up. South Africa during apartheid never had any of that at their disposal.\n\nAdditionally, once the dissidents are apprehended, they can be disposed of in any way, as there are no due process guarantees in Saudi Arabia. If someone is caught acting against the government, they can be placed under house arrest forever, life in prison, executed--whatever the government seems fit. The legal system in Saudi Arabia isn't the most transparent. It is not a public right that court documents/hearings be presented to the public.\n\nedit: also the fact that SA (edit2: Saudi Arabia) is a Muslim country plays a part too (smaller though, IMO). The people in Muslim countries typically justify the anti-woman rhetoric because it is in Quran and is the Islamic way of living. So speaking out against that would be seen (and condemned by many) as speaking out against Islam, and Muslims are typically terrified of being labelled thusly.\n\nedit2: After some replies, I realize that the above edit may be a bit off. I myself know that the Quran does not explicitly instruct men to oppress women. But male dominance/female subordination is depicted in the Quran, and I know that *some* men in the Muslim world use this as justification for such behavior now. Furthermore though, I concede that this behavior is entrenched moreso due to social norms and not religious. I should modify my above edit to read that speaking out against *the status quo* is not done very often in the Islamic world, unless it is to advocate being \"more\" Islamic.",
"The Right doesn't often criticise Saudi Arabia because it's a regional ally of the US and the EU, and it's a serious oil producer. It's on our side.\n\nWhen it does, it's very rarely Saudi Arabia that's the real target - right wing pundits will refer to the problems Saudi women face, or the barbarity of the justice system, but generally just as a way of attacking muslim minorities in their own nations. No right winger has, to my recollection, ever suggested we stop buying Saudi oil or selling them arms, because the first is 'free market', and the second is 'geopolitical realism'.\n\nThe Left doesn't criticise Saudi Arabia because, first off, they don't want to be lumped in with the Right-wing critiques, which tend to be means to the end of culturally and economically marginalizing local Muslim minorities. Secondly, leftwingers tend to be suspicious of western condemnation of middle-eastern societies, since it's (in the last twenty years or so) been the root of the doctrine of 'humanitarian intervention', which was a total shit-show. \n\nThirdly, and this is the crucial bit, the anti-apartheid movement was started in South Africa, and the international left simply stood in solidarity with it, and behind it. Any left-wing movement against the house of Saud would have to grow out of Saudi dissidents who (sadly, since Saudi Arabia are much less economically marginal than South Africa was) typically end up being murdered or tortured, while western governments turn a blind eye, and keep on arming the bastards to 'aid regional stability'. ",
"I have lived in Saudi all my life, most of its citizens are happy with the way things are. They have been living like this for centuries and it is a part of their culture. Women are looked after and treated with respect. They wear abayas just like everyone else wears clothes. To them abayas or those black veils represent modesty. Most of the Saudi females I know tell me that they are happy because most of the time they have immigrants as drivers and butlers to take care of them, therefore they don't feel the need to drive. \n\nTL;DR it is a part of their culture and they are happy with the way things are. I am speaking about the general consensus, obviously there are some who would like more freedom",
"Because the Middle East is bad enough. Imagine an unstable Saudi Arabia and an unlimited supply of oil money.",
"In South Africa, there was a small minority (~10% of the population) in power, trying to oppress and control the remaining ~90%. The numbers just weren't workable. \n\nOn the other hand, around 50% of the Saudi Arabian populace (the men) control the country. So numbers aren't on their side per se, but they're also not against them - and it's hence much easier to maintain the status quo.",
"Because it's desert. It'd have to be \"cactus roots\".",
"Not an expert here but always happy to submit an unpopular opinion.\n\n I have visited KSA ( Kingdom of Saudi Arabia). Just from observing life there I have seen a society that's very attached to their traditions and values. These traditions and values are very different from ours ( I 'm an Eurpean male), yet shouldn't we respect them just as we expect ours to be respected? What I have seen (again, the testimony of my eyes, nothing else) is a society where most of the shops in posh modern malls are aimed at women (jewellery, frangrance, fashion, shoes, you name it) men are discouraged from entering shopping centres at certain times and at others it is almost solely men who work in shops and women( in nikabs) who do the shopping with their husbands and brothers having to drive them there and carry their bags. I have talked to some female western teachers and when they go outside their for- westerners- only compounds, and show their faces, it is the Saudi women who hiss at them. \nI understand that isolated incidents do happen but I do not think Arabs intend to overthow American values because a black kid was shot by a cop.\nTLDR: I think we in the West might be trying to impose our values on a society we do not know. ",
"Saudis have actually bought out protesters before. You seriously underestimate how much money these guys have. Check out the rainbow shiek. Or all of their palaces. The royal family itself is gigantic. ",
"_URL_0_\n\nSaudi Aramco is the largest and most powerful company on Earth. It could buy Apple, Microsoft, Google, Ford, and dozens of other huge companies if it wanted to. They have more power than most governments and the US economy is dependent on keeping them happy. Most people have difficulty imagining that level of power.",
"No ones mentioned sanctions yet, although I guess that's implicit in the \"because oil\" reason. Apartheid was sufficiently abhorrent at the time for most of the world to inflict sanctions of various kinds on South Africa. (I'm unsure how much that actually helped in the end to rid South Africa of Apartheid). But without that external support, any equality movement is always going to be difficult. ",
"Because Islamic people, Saudi women, and sorcerers do not have the lobby black people do.",
"The U.S. government, defense industry, intelligence apparatus, and military are far too friendly with the Saudi Royal family to allow any movement like that to gain traction AND media attention. Same with Israel. Friendly nations don't let their people talk negatively about each other, even if what is said is true.",
"There are a million reasons why any given country might come under international sanction and opposition, as well as a million factors that play into whether or not such campaigns are successful and what resources that regime has at its disposal to prevent and silence dissent.\n\nTop comment is only part of the answer. Saudi Arabia definitely has a huge repressive capability which it has achieved through its oil wealth, but the question goes the other way too -- how could it control the oil wealth and prevent parts of Saudi Arabia from flying off into the control of dissenting factions without the \"internal security\" that it has? The answer is a number of factors that precede Saudi Arabia's modern creation, namely the British exploitation and control of the area and the building of a modern state apparatus that is greater than the sum of its parts. The use of Arab and Muslim autocrats to do the \"dirty business\" of European countries makes these regimes vital assets not only to the local ruling class, but to other collaborating states and the dominant players in the international economy. When the dirty business is over oil -- a major industrial input -- it can have international significance if there is instability or market fluctuation. That means that, provided it does not interfere excessively in major political priorities of the states which are backing it, it can get away with murder. Moreover, Saudi Arabia has been able to maintain its status as a patronage state -- the vast majority of its population, with the exception of migrant laborers from Egypt, India, Bangladesh, etc -- are given huge state subsidies to pay for everything from housing to food to education to medical aid, etc. \n\nIn contrast, South Africa and the international boycott campaign against it had a distinct history. SA isn't a major oil producing country, and its internal population was subject to a racial caste system that undermined basic rights for about 80% of the population on race and ethnicity alone; hardly any black guys driving with porsches through the bantustan. Outside of being a powerful image of blatant discrimination that could be effectively marketed to legitimize other anti-racist and anti-colonial struggles, it also hit home to organizers in Western countries that associated Apartheid with their own histories of racism. Furthermore, the excessive levels of US support for South Africa, without the rest of the world or other regimes seeing an equivalent benefit, contributed to emphasizing South Africa as a blight on the US record during and well after the Cold War. The additional instability that came with the inability of the South Africans to effectively manage a Bantustan system likewise also added negative attention. All of these factors slowly but surely turned South Africa's Apartheid system into a liability rather than an effective tool for major stake-holders, so making a transition to a nominally \"equal\" society -- albeit one that still has incredible levels of discrimination -- was a strategic move. None of these factors exist for Saudi Arabia.\n\nI should also point out that much of this analysis also applies to the increasing international climate against Israel -- and provides better ways to look at the issue than simply reducing it to international \"anti-Semitism\", which would not explain how Israel (like Saudi Arabia and South Africa) was able to achieve such high levels of Western support in the first place, and would not explain the changing actual attitudes toward Jewish people throughout the West and the United States. \n\nI also find the statement in the top comment about Muslim attitudes quite ignorant. Muslims throughout the Islamic world have condemned Saudi Arabia's anti-woman stances, quite openly, and indeed there are many narratives talking about the excesses of \"takfirism\" and the backwardness of such states and their internal policies. Syrian supporters of the regime of Bashar Al Assad, for example, including the significant number of Sunni and Shi'a Muslims who supported him, maligned the revolution against his regime by pointing out that it was, in some ways, connected to the regional pursuits of Saudi Arabia; they used Saudi Arabia's horrible record on democracy, including its discrimination against women, to mock the notion that such a country could support democracy in Syria and thereby sought to malign the movement against the Syrian regime as a whole. But those Muslims -- like non-Muslims -- often use the excesses of Saudi Arabia or the Taliban to make their own sexism look acceptable, much in the way some of the most anti-feminist campaigners in the US (like the guy who argued that rape cannot produce pregnancy and the rest of his political wing) suddenly become equal rights advocates when it comes to Islamic countries that they want to bomb. In either case I hardly think that's a factor at all in propping up Saudi Arabia, it would not explain the rejection of Islamist groups elsewhere or its conflicting political history or the varying views of Muslims throughout the world on gender roles. \n",
"There are movements but not big enough to achieve anything. Besides, they don't have the monetary incentives to do so. You don't see a big government upheaval unless the people are on the streets, jobless, homeless and without knowledge when the next meal is. Poverty is essential to a revolution.",
"I have no direct knowledge of the situation but here's one obvious difference:\nIn South Africa, the oppressed class was gathered together and forced to live together in squalor. This situation almost guarantees the formation of a resistance movement.\nIn Saudi Arabia, the oppressed are spread throughout society, and the oppressors are their loved ones. It would take a significant amount of thought, education, and exposure to Western ways for either sex to even recognise that oppression was taking place. Even if they do, they're in no position to band together and organise in opposition to it.\n\n\n",
"The racial vector is an important reason. It is hard for women to organize resistance because they are born to mothers and fathers; racial divides, on the other hand, are genetic -- black people are born to black people. \n\nThis is to say that the oppression of women begins in the home, whereas the oppression of racial minorities begins in the public world. So it is hard for women (or gays, or any minority that is born into heterogenous homes) in Saudi Arabia (or anywhere else) to organize into a social group with a cohesive message.",
"Just a thought:\n\nDuring apartheid, or indeed the civil right movement in the USA, it was clear cut, black people wanting rights refused to them by white people.\n\nIn Saudi Arabia, or other countries which deny women rights, it's not just the government who is against you, it's your husband, father, brother, cousins, sons, maybe even your mother too.\n\nIt's one thing fighting a faceless state, it's another fighting the people who raised you. Perhaps it's like domestic abuse, someone in the street hits you, you hit them right back and call the police, in the home, it frequently becomes far more complicated.",
"Because you cant say something bad about Islam, that makes you a racist!",
"They have something a lot of countries need, so the west looks the other way. \n \nSame reason the west doesn't care about oppressed Asian and child labor or the list of human rights abuses in China while tiny Cuba still remains embargoed. ",
"Saudi Arabia is part of the Wahhabi school of Islamic thought and interpretation. It is an ultra-conservative interpretation of the Islamic texts, this means that women are placed in a secondary and subservient position to men. The accuracy of their interpretations is debatable\n",
"Mostly because the South African government even at its worst never came to your house and blew your shit up or cut off your head. When people choose a \"cause\" there is usually a risk reward trade off. Going up against the global jihad engine will get you killed quickly. \n\nNotice how a lot more artists are willing to urinate on a bible versus a Koran. The trade off here is clear. You can make the same message and garner the same benefits with less personal risk.\n\nUsually those who fight for a \"cause\" will choose the one least risky. It's doubtful that any of those who fought against apartheid in South Africa would have done so if it meant a risk to themselves....meaning the foreigners. As for whether they truly cared about the people they fought for as opposed to the cause....ask yourself how many of them are trying to help South Africa develop as a country after they won the cause.",
"Once the oil runs out or we don't need it, then I'm sure there will be one.",
"The answer is really simple actually.\n\nSouth African apartheid was created and run by white South Africans, who were and are Anglo Saxon just like the citizens of the western nations which supported them. They did this against an overwhelming native African majority.\n\nApartheid also was in directly contradiction to the values of the societies which were supporting it and fighting against the prevailing winds of change in those societies.\n\nIn essence, South Africa was implementing a policy they couldn't justify in their own society and required the support of other nations to implement it. When those nations turned against it, the government actually eventually dissolved itself.\n\nThe same thing could actually happen in Saudi, but it would require dramatic change in the role of women throughout the rest of the middle east. If the rest of the Arab world treated women as equals, Saudi Arabia would likely have to follow. Our opinion just doesn't mean shit."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[
"http://en.wikipedia.org/wiki/Petrodollar"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
|
435vbj
|
"the greek political crisis in the middle of the fourth century B.C"
|
So for this presentation I had to read about the origins of the concept of the constitution. The text says a political crisis (see title) lead athenian philosophers (Plato and Aristotle) to question if their current democracy (that was about 100 years old at the time) was a cause of this crisis or it was something else. The text goes through what they meant by said crisis (a shift to a more naval/economic focus) but doesn't really go into a lot of detail into why. I dod some research of my own (not for the presentation exactly, just mere curiosity) and this is what I found:
The greeks were again divided in their Poleis after they defeated the persians and Athens and Sparta fought for hegemony in the region.
Since thats what I found and nothing really too trustworthy I started to speculate, since this happened after the Peloponnesian War, maybe the Athenians didn't want to fight the Spartans in land an sought to become a Naval and Trade power to assert the control of the area.(??)
basically my questions sum up:
1. How did this crisis affect the state of the democracy? was it factionalism or some other new factor of a merchant nation like immigrants or such?
(related to 1.) Why would a shift to naval/trade focus affect the greek democracy? (read a bit of what Aristotle said, but didn't really get where he got his points from)
2. Did the athenians look to ally the other Poleis to defend themselves for the "now dominant" Spartans?
3. Was this in-fighting what weakened the Greek City-States allowing for Macedon to then control the region (Alexander's dad and all that)?.
I figure this may belong to the ask for help subreddit, but since I'm asking by my own curiosity and my assignment is about constitution and not ancient geopolitics this isn't technically homework. Please let me know if I'm on the right track or feel free to correct me since I'm not to versed in ancient history.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/435vbj/the_greek_political_crisis_in_the_middle_of_the/
|
{
"a_id": [
"czfsi30"
],
"score": [
2
],
"text": [
"It seems like the original text hugely oversimplified the issue. It also relied on the outdated notion of a \"fourth-century crisis\". I will try to clear a few things up.\n\nAthens is considered to have become a democracy through the reforms of Cleisthenes about 507 BC. Throughout the century that followed, the political system gradually \"radicalised\", which is to say that the old rich elite were increasingly stripped of their traditional powers while efforts were made to include the general population in the democratic process. Since many of the Athenian poor served as rowers in the fleet while the rich traditionally served as heavy infantry or cavalry, the democracy is sometimes said to have become more \"naval\" in step with its \"radicalisation\". The more poor people took part in policy-making, the more focused on naval expansion that policy became. Many Athenian authors, themselves invariably rich men, regarded democracy as \"mob rule\" by the \"naval mob\" (*nautikos ochlos*).\n\nThe backlash occurred at the end of the Peloponnesian War. In 411 BC, the democracy was replaced by the oligarchy of the Four Hundred. This was short-lived; a wider oligarchy called the Five Thousand soon took over and restored the democracy. In 404-3 BC, after Athens' defeat in the Peloponnesian War, the democracy was again dissolved and the city fell under the sway of the brutal oligarchy of the Thirty, supported by the wealthy cavalry. Their reign of terror was cut short, however, by a democratic insurgence, and the democracy was restored a second time.\n\nThe system of government put in place in 403 BC is the system described by Aristotle (or one of his students) in the *Constitution of the Athenians*. As a democracy, it was even more radical than its 5th-century predecessor; it introduced revolutionary things like pay for Assembly attendance, allowing even the poorest citizens to take part in the democratic process. It was also one of the most stable political systems in Classical Greece, remaining largely unchanged and unchallenged for over 80 years, until the Macedonian Antipater forcibly dissolved the democracy a final time in 322 BC.\n\nNow, since the 4th century BC saw nothing like the Athenian Empire of the century before it, and the city-states of Greece seemed unable to invest in public works or warfleets on the scale Athens had during the 5th century BC, the period has traditionally been seen as one of decline or even crisis. However, this view is increasingly questioned by scholars. Many Greek states appear to be doing very well in this period. Indeed, more efficient taxation and public finance meant that Athens was approaching the prosperity it had known during the height of its empire - but this time it generated that wealth all by itself. Though its hopes of building a new empire (fuelled no doubt by the \"naval mob\") were crushed during the costly Social War (357-355 BC), its trade and population were growing, and it may have maintained a fleet on a late-fifth-century scale during the final years of the democracy.\n\nYour original text appears to have conflated two unrelated issues: the radicalisation of the democracy (mostly a 5th-century development) and the \"crisis\" of the fourth century (mostly an invention of modern scholarship). There is little indication that Athens was becoming more \"naval\" in the course of the 4th century, or that this caused any kind of crisis. As I said, the political system was stable, and the citizens mostly benefited from the state's economic and military policy. \n\nPlato and Aristotle, meanwhile, were suspicious of democracy primarily because of their own social station. The rich (who paid all the taxes) were rarely in favour of being ruled by the masses (whose wages were often paid by the state). Their deliberations on ideal government fit into a long Athenian tradition of debates over how the political system could be improved.\n\nI believe this answers question 1. Regarding immigrants, they did not have voting rights in any Greek community and only served to make a state more populous and prosperous. Their presence or absence would not have affected the political system.\n\nAs for question 2, yes, after the Peloponnesian War the Athenians repeatedly made alliances with other states against Sparta. During the Corinthian War (395-386 BC) they joined together with Corinth, Boeotia and Argos against Sparta. During the Boeotian War (378-371 BC), they were allied with Thebes against Sparta, and also had the full weight of the Second Athenian Confederacy behind them. After this, Spartan power was broken and the balance of power shifted. During the wars of the 360s, Athens actually made an alliance with Sparta against Boeotia. It gets more complicated from there.\n\nAs for question 3, the rise of Macedon is a complex story that cannot be explained simply by pointing to the wars of the Greek city-states. No doubt Philip II repeatedly took advantage of the weakness of his southern neighbours, but he also suffered setbacks in his wars against the Greeks, and Athens in particular proved a tenacious opponent. But this might be worth another thread.\n\nI hope this helps. Let me know if anything is still unclear."
]
}
|
[] |
[] |
[
[]
] |
|
1gypxc
|
Prior to the Russia's conquest of the far east, what people/tribes/nations lived/occupied those lands? Did anyone lived in Chukotka for example? What were those people's traditions?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1gypxc/prior_to_the_russias_conquest_of_the_far_east/
|
{
"a_id": [
"cap9acx"
],
"score": [
6
],
"text": [
"Numerous people lived in Siberia and the far east of Russia, far too numerous to list them all here. These people tend to be trappers, herders, hunters, and the like.\n\nGenealogically, there is a strong relationship to the people who live(d) here as do in Alaska, including Inuits and Aleuts. Yakuts, Chukchi (who lived in Chukotka, which you specifically mentioned) also lived in the far east. Depending on how far west you want, there are was/is an incredibly diverse population here. (Wikipedia, incidentally, has lots of basic information on these groups, although relatively little historical information about their interaction with Russians for the most part).\n\nYuri Slezkin's *Arctic Mirrors* talks quite a bit about the people of the North and is probably the best book I can think of that gets towards answering your question. (note, not necessarily the far east) _URL_0_"
]
}
|
[] |
[] |
[
[
"http://www.amazon.com/Arctic-Mirrors-Russia-Small-Peoples/dp/0801481783"
]
] |
||
2n11or
|
how am i supposed to use public bathroom seat protectors?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2n11or/eli5_how_am_i_supposed_to_use_public_bathroom/
|
{
"a_id": [
"cm9cvlw",
"cm9d30x",
"cm9dkw4"
],
"score": [
2,
2,
2
],
"text": [
"You tear out that little center bit, it is probably already open at one end.\n\nThe reality is you don't need to use one at all from a disease stand point. If the seat is generally dirty then sure, go ahead, but if you are worried about germs then don't bother - it doesn't do anything about those.",
"The center part goes in the water, so when you flush it pulls the whole thing down. Your better off wiping the seat and putting a pad of wadded paper in the water to prevent splashes, the seat protectors are just a waste of trees. ",
"Well this is a common complication.\n\nFirst gently moisten your right index finger with your tongue. Rub it on your right thumb in a clockwise rotation 3 times. This setup will now be called the \"eagles claw\".\n\nRepeat this with your left hand but do the rotation counter clockwise 3 times. This design will forwardly be called the \"falcons claw\".\n\nCarefully remove the seat protector from the housing. Hold tightly with eagle claw for maximum grip. \n\nUnzip your pants with freshly moistened falcon claw. \n\nCarefully pull out your manhood as to not get penal hair caught on zipper. (falcon)\n\nKeep carefully gripping seat protection with eagle claw. \n\nBegin urinating in sprinkles on the toilet seat for stickyness.\n\nPlace the seat cover on the seat. Let sit for 10 seconds while the seat protection and urine bind to form a temporary adhesive. \n\nPull down pants and sit on toilet seat protection. It may feel wet but it is not. Ignore the sensation and focus on taking the shit you came here for. You are now a man. \n\nDisengage eagle and falcon claw. \n\nFor directions on how to wipe your ass, see /r/transfomationfromeagletoflatbreadsetup\n\n\n"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
2ukww3
|
how did the banana peel become synonymous with slipping and falling?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2ukww3/eli5how_did_the_banana_peel_become_synonymous/
|
{
"a_id": [
"co9ammx",
"co9bh2g",
"co9lk50"
],
"score": [
13,
10,
3
],
"text": [
"Bananas were common street food in the US during the early 1900s, people would throw the peels on the ground, not in the trash and people walking would slip on them. Hilarity ensuesd\n\nNote: It wasn't the banana you are familiar with, it was a different and now rare vareity (it used to be common) called a [Gros Michel banana](_URL_0_) . It was more dessert-sweet like than the modern cultivar the [cavendish](_URL_1_) \n\nThis helps make more sense of why a banana would be a street food, it was a sweet desert.",
"There are many theories behind the origin of the ‘Banana Peel’ joke made popular by the slapstick comedy films of the early 20th century. One hypothesis is that banana peels were representative of the pollution in New York City circa the turn of the 20th century. Public campaigns highlighted the danger of leaving banana peels on the ground (as well as other trash), but particularly the banana due to its highly visible color. The campaign against errant banana peels eventually led to the widespread use of municipal garbage facilities. A different theory is that the banana peel was a specific euphemism for dog feces – it was originally noticed that there was lots of dog waste on the streets, and people slipped in it, which is funny. But it is not a particularly practical device when used on stage, especially for family audiences, so they were replaced by banana skins, which are family safe, even though they’re not quite as slippery as turds, and certainly less abundant.",
"My understanding is that the original gag was that people were slipping over in faeces, (bear with me) this came from late 19th / early 20th century comedy, a pre-automotive world that was covered in horse poop.\n Faeces is slippy as hell and people slipping over on it would probably have been a fairly common joke in the victorian age, akin to slipping on black ice. \nThe banana skin was a less gross alternative used onstage and with the advent of movies and slapstick comedy, It's also less gross for the actor, While the audience still knew what the banana represented.\nAs time progressed we lost the common gag of slipping over in poop but still retained the banana, thus the jokes meaning has been lost on us."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Gros_Michel_banana",
"http://en.wikipedia.org/wiki/Cavendish_bananas"
],
[],
[]
] |
||
dqq13o
|
pass, passed, and past, grammar explanation needed
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/dqq13o/eli5_pass_passed_and_past_grammar_explanation/
|
{
"a_id": [
"f68ci7r",
"f68edyp"
],
"score": [
5,
4
],
"text": [
"\"Pass\" is a verb with lots of definitions. (it can also be a noun, but that isn't important to the context you're asking about here) \n\"Passed\" is just the past tense of \"pass.\" \n\"Past\" can be a noun (\"apartheid is a thing of the past\"), an adjective (\"past tense\"), or a preposition (\"we went past the store\").\n\nYou've used it as a preposition here. You used \"past\" correctly, but you're using \"age\" *incorrectly.* It should either be \"ages\" or \"aged,\" depending on the context.\n\n\"My mother always looked young, she never aged past 25.\" \n\"Taylor Swift still looks young, she never ages past 25.\"",
"The **preposition** (or where something is) is \"past\".\n\nE.g. take the turn past the next shop\n\nThe **noun** for time previous to now is \"past\".\n\nE.g. there was no electricity in the past\n\nThe **verb** to move beyond something or exchange something is \"pass\"\n\nE.g. please pass me the salt\n\nThe **past participle** of this verb, meaning the action is completed, is \"passed\"\n\nE.g. I passed a police car on the way here\n\nIt may be throwing you off that the \"past participle\" of pass is \"passed\". That's all a bit much to absorb maybe. But just remember the \"past\" in \"past participle\" is there referring to time and that might help.\n\nSo \"pass\" and \"passed\" are the verb forms. The action of moving beyond or exchanging. Something only \"passed\" something else when referring to its action. It answers the general question \"what is it doing? What did it do?\"\n\n\"Past\" is in either case about location. In space or time. It answers the question \"where is it? Or when did it happen?\""
]
}
|
[] |
[] |
[
[],
[]
] |
||
kkq9s
|
How is my brain able to make the most beautiful scenery, full of details, in my dreams and when I try to do the same while being awake I have the hardest time.
|
askscience
|
http://www.reddit.com/r/askscience/comments/kkq9s/how_is_my_brain_able_to_make_the_most_beautiful/
|
{
"a_id": [
"c2l1lei",
"c2l1lei"
],
"score": [
7,
7
],
"text": [
"Parts of your brain, which remain active while you sleep, interpret the \"mess\" the rest of your sleeping brain makes. That part of your brain is already in use by perceiving the real world around you while you are awake. \n\nIf you deprive yourself of outside stimuli, you will start to hallucinate (Ganzfeld effect).\n\nAlso your judgment of what is beautiful is probably impaired while you sleep ^_^",
"Parts of your brain, which remain active while you sleep, interpret the \"mess\" the rest of your sleeping brain makes. That part of your brain is already in use by perceiving the real world around you while you are awake. \n\nIf you deprive yourself of outside stimuli, you will start to hallucinate (Ganzfeld effect).\n\nAlso your judgment of what is beautiful is probably impaired while you sleep ^_^"
]
}
|
[] |
[] |
[
[],
[]
] |
||
2348al
|
what are the purple colour-schemed textures for in 3d video games?
|
Like [these](_URL_0_)?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2348al/eli5_what_are_the_purple_colourschemed_textures/
|
{
"a_id": [
"cgt92o2"
],
"score": [
3
],
"text": [
"Although I can't say I'm completely sure, this appears to be a relief map. When you are making 3D computer models, it costs way too much computing power to get the shape of an object right to the millimeter, because this involves putting a lot of polygons (little triangle shapes) in the model. Instead, a relief map is used. It's a little map that is much like [the diffuse texture](_URL_0_) wrapped around an object, but instead of colour it tells the game the small-scale height differences in the model. This is far cheaper to make and requires less calculations when you're playing the game."
]
}
|
[] |
[
"http://puu.sh/8a0nH.jpg"
] |
[
[
"http://apocalypsecity.net/img/texture.jpg"
]
] |
|
15bgpn
|
Sun Protection Factor - SPF - is higher than 30 really required for "white adult Caucasians" - sorting out marketing from science
|
It's obvious that marketing plays a huge role in sunscreen lotions. I see people half jokingly say "to get SPF 500" - and the marketing reflects this simplistic numerical logic (higher is better). It reminds me of the "higher Mghz" is better between Intel and AMD CPU frequency on computers.
Assuming the products are not outright fraudulent - and truly delivery the "4 hours of waterproof SPF 30 protection" they claim - is there really any reason to reach for SPF 45 or SPF 50 products from the same producers?
P.S. We just had Summer Solstice in the south half of the world ;)
|
askscience
|
http://www.reddit.com/r/askscience/comments/15bgpn/sun_protection_factor_spf_is_higher_than_30/
|
{
"a_id": [
"c7levha"
],
"score": [
2
],
"text": [
"Sun protection factor is essentially a multiplier for your bodies natural resistance to burning.\n\nIf you take 20 minutes before you turn red in the sun and I take 10 and we both properly apply SPF 15 you would be resistant to burning for 300 minutes (20*15) and I would be resistant for 150 (10*15).\n\nSPF 50 would give you 1000 minutes of protection and me 500.\n\nNow there are some problems with these numbers.\n\nSweat and water will wash away the protection faster along with friction from your clothing or other contact.\nYou also need to have applied it properly which is 2mg/cm^2 most people use way less.\n\nSunscreen also only stops UVB rays not VUA but you can look for additional ingredients such as zinc or titanium dioxide in your sunscreen to help protect you. There is no standard protection classification for these additional additives so you would have to try to find tests for your specific brand.\n\n1. The American Academy of Dermatology suggests you use one ounce of sunscreen on your exposed body parts ( arms legs head neck more if you are shirtless. \n\n2. Apply 20 minutes before going out.\n\n3. Use a minimum of SPF 30.\n\n4. Reapply every 2 hours. Possibly more often if you are heavily sweating or in the water.\n\nI use SPF 50; overkill? Possibly. But melanoma causes 75% of skin cancer deaths even though it only causes about 3% of the skin cancer cases. UV exposure is a risk factor for melanoma. \n\nTL;DR Unless you burn very easily just follow the AAD guidelines and you should be fine."
]
}
|
[] |
[] |
[
[]
] |
|
1z5wmg
|
is there a scientific, historical, or sociological explanation as to why women like getting flowers?
|
Is it "just because?"
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1z5wmg/eli5_is_there_a_scientific_historical_or/
|
{
"a_id": [
"cfqtbfe"
],
"score": [
5
],
"text": [
"It isn't as simple as \"women like getting flowers\". Flowers have been used as symbols or given meaning for thousands of years; the Hebrew Bible contains references to henna blossoms as a symbol of affection. The giving of flowers is a method of symbolic communication, which is why they may be appreciated."
]
}
|
[] |
[] |
[
[]
] |
|
f6h3up
|
Why did Hitler wait until the day before he killed himself to get married?
|
Pretty much the title. Him and Eva Braun knew each other for pretty much 16 years but didn't get married until they knew they would kill themselves the next day (and Hitler was 56 at the time). Geobells, Göring, Himmler, Heidrich, Hess, Bormann, etc. were all high ranking Nazis who got married. Why was Hitler so different in that regard?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/f6h3up/why_did_hitler_wait_until_the_day_before_he/
|
{
"a_id": [
"fi7d5ng"
],
"score": [
5
],
"text": [
"According to Otto Wagener (SA Chief of Staff from October 1929 through December 1930), Hitler declared to his party comrades that he was living in politics and rejecting his private life, and had never planned to marry at all. In a personal conversation with him, Hitler said: “I have another bride - Germany! I am married to the German people, to their fate! \\[...\\] No, I can not marry, I have no right. \"\n\nNevertheless, relations between Hitler and Brown began to strengthen after 1931, although it is not known for certain how much they became closer and how they developed. During the election campaign of 1932, Heinrich Hoffmann (Adolf Hitler's official photographer, who was a member of Hitler's intimate circle) sometimes took with him \"his little lab technician Eva Braun\", \"which Hitler was glad to see in the evening at the table in order to get a little distracted.\"\n\nThe existence of a mistress did not fit into the successfully cultivated myth of the lonesome, godlike führer who sacrificed his personal life for the cause of the Germany. Only at the end of the war after Hitler's suicide did the German public learn that he had a love interest and many refused to believe it.\n\nSource:\n\nEva Braun: Life with Hitler, By Heike B Görtemaker, 2011"
]
}
|
[] |
[] |
[
[]
] |
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