title list | over_18 list | post_content stringlengths 0 9.37k ⌀ | C1 list | C2 list | C3 list |
|---|---|---|---|---|---|
[
"Does the earth continually produce new oil?"
] | [
false
] | null | [
"Several people have noted that oil is still being produced, albeit slowly. \nIt is interesting to note that coal is essentially not being produced at all. Coal formed from early wood that could not be decomposed, but since fungi have since evolved the ability to digest wood, undigested wood no longer occurs in lar... | [
"Yes, but extremely slowly compared to the rate that we use it. The process from living organism to oil takes milions of years and some of the oil we drill up is hundreds of milions of years old.",
"In comparison, oil has only been used by humanity for the last 2 centuries and we've already used up a large part o... | [
"I've seen estimates in the 25 - 50 barrels per day range for global oil creation. (Our usage is somewhere about 93 millions barrels a day)"
] |
[
"Why is a neutron-neutron (or even greater) configuration impossible?"
] | [
false
] | It seems a neutron-neutron configuration would be more stable than, say a proton-proton configuration where the Coulomb forces are present. Yet the latter may exist (albeit extremely unstable), but I see no mention of the former as even a possibility. Why is this? | [
"/u/RobusEtCeleritas",
" has a pretty good answer but it may be hard to understand without previous knowledge of nuclear structure, I'll try to explain what's going on more simply.",
"In a nucleus you have nucleons which exist in different energy levels just as electrons exist in orbitals. If you have two nucle... | [
"You are correct that the diproton is more unstable than the dineutron due to Coulomb effects. However both of them are unbound, even neglecting Coulomb effects. Ignoring isospin symmetry breaking (due to EM forces and the proton-neutron mass difference), the diproton and dineutron are the same system as far as the... | [
"Ah, so the nuclear force is dependent on spin. Thanks!"
] |
[
"Smart people of reddit, in a perfect scenario--what would be the fastest a human could possibly travel on a bike with only leg power?"
] | [
false
] | [deleted] | [
"Around 130 km/h: ",
"http://en.wikipedia.org/wiki/Cycling_records#Speed_record_on_a_bicycle"
] | [
"Totally flat smooth surface with no wind and high tech aerodynamic helmet and suit."
] | [
"Totally flat smooth surface with no wind and high tech aerodynamic helmet and suit."
] |
[
"Why do nuclear fission and fusion give off energy?"
] | [
false
] | null | [
"Hello,",
"This is addressed in our FAQ.",
"Cheers."
] | [
"How do I get to the FAQ?"
] | [
"It's ",
"here",
"."
] |
[
"Is there a known algorithm used to define how difficult a word is to type?"
] | [
false
] | I've looked around and didn't find anything on the subject. Please excuse me if I just didn't google hard enough. But the current factors of word difficulty that I have thought about are: So my own rather unscientific definition of how difficult a word is, is: WordLength + HandChanges + (L1L2_distance + L2L3_distance*L1L3_distance + R4R5_distance + ...) | [
"Not an answer, but this seems like a question related to Information Theory similar to the ",
"Levenshtein Distance",
", which measures the minimum number of edits required to turn one word into another word. You may find something similar to what you're describing in the same field of Information Theory."
] | [
"I would measure the maximum number of times the same finger needs to press a different key. If each finger only needs to press one or fewer keys, then the whole word could be typed in a single well timed mashing motion. It's also easier to roll your fingers from the pinkies towards index fingers. ",
" is easier ... | [
"It depends... How big are your hands?"
] |
[
"Are climate change and global warming interchangeable terms?"
] | [
false
] | null | [
"Correct, they are not interchangeable. "
] | [
"No. The climate can change in lots of ways including more extreme weather patterns."
] | [
"Sorry, do you mean, no they aren't interchangeable terms?"
] |
[
"What is dark energy?"
] | [
false
] | I recently read an astronomy book that mentioned it, but I am still confused. Sorry if the question is a bit broad. | [
"Basically it's a density that space has, even when there's seemingly nothing there. This drives the accelerating expansion of the universe. We know that the universe is accelerating from various cosmological measurements (like the recession speed of distant supernovae), but the actual nature of dark energy is unkn... | [
"To add more detail/context to the question itself:",
"Dark energy is mentioned in articles and magazines and books for the scientifically literate (but not at all experts or even physics majors or minors) in keeping with the answers I've already read in this thread, but it still seems a bit... mysterious? I'm s... | [
"Dark Energy is the term applied to the ~73% of the matter-energy density in the Universe.",
"Using observations of the CMB, we can determine the total mass concentration, the ratio of regular matter to dark matter, and the total concentration of energy + mass, i.e. regular matter, dark matter, and dark energy.",... |
[
"What is the reason that men and women are athletically different?"
] | [
false
] | I'm not trying to be sexist, but I find it to be fact that the average man is more athletic than the average women. I've grown up with a sister, and she has never been able to throw a ball gracefully. Is it because the culture of being a boy, generally, focuses on developing athletic talent? Or is it more of physical reason? Does a man's higher muscle:weight ratio allow for more athleticism? or, lastly, does a man's brain have more developed motor control? I'm leaning toward the brain thing. I just figure that a man's motor control is more fine tuned. Something possibly to do with the cerebellum? I'm shooting in the dark here | [
"Men's genetics have been fined-tuned over the last couple million years to by more physically apt to overcome and meet the demands of hunter-gathers, followed by the relience on those same athletic requirements even once we became sedentary. The difference is also reinforced by types of things that young boys and ... | [
"My wife has said it's not sexist if its a fact."
] | [
"Butts and Nuts."
] |
[
"Why do transformers explode so spectacularly in severe storms?"
] | [
false
] | One just blew up outside of my house last night in the severe thunderstorms we've been having. Bzzzzzt! Bzzzzzzt! BANG BANG, jets of blue flame spurting out. When power transformers blow, their death throes are pretty spectacular. What causes all the fireworks? And what about downed power lines causes them to fail in this manner? | [
"They run at very high voltages to facilitate more efficient transport of electricity, so what you are seeing is probably a combination of electrical arching and metal components melting and vaporizing. Squirrels routinely blow them up too.",
"Either that or it's those pesky Decepticons at it again!"
] | [
"Most pole transformers are filled with a non-electrically conductive oil to help facilitate cooling, some of this probably vapourizes and ignites when the transformer overloads, the pressure from this vapour probably also helps with the loud noises as it bursts out of its container."
] | [
"<layman>",
"Very large ",
"capacitors",
" shorting out would cause a heck of a show, but I don't actually know if that is what is going on. A tremendous amount of energy can build up and be stored in a capacitor, and if it shorts and discharges all at once, you'd see that energy released as light and heat a... |
[
"Why, on a evolutionary and biological basis, are we repulsed by each others body odor?"
] | [
false
] | null | [
"There was an experiment on TV once -- they took four or five guys, gave them shirts, had them work out, then took the shirts back and labeled them. They gave the shirts to four or five girls without telling them who the guys that had worn them were, had them smell the shirts, and then rank them for preference. Eac... | [
"This sounds interesting but the sample size is quite horrible."
] | [
"As a public transport using resident of New Delhi, I can confirm this.",
"Smell like piss? We won't mind."
] |
[
"Speed of light and quantum entanglement"
] | [
false
] | As I understand special relativity, as something approaches the speed of light, time, from its perspective slows down. Therefore, would it be true to suppose that a photon, traveling at the speed of light, does not experience time? Further, because no time is experienced by the photon, does it exist at both it's start and end point simultaneously? Is this or could this be the cause of or the effect we perceive as quantum entanglement? | [
"As I understand special relativity, as something approaches the speed of light, time, from its perspective slows down.",
"As evanwestwood already pointed out, this is not correct. In your own rest frame, your clock will tick at its normal rate. Other moving observers, however, will measure your clock ticking a... | [
"According to its frame of reference, the photon \"experiences\" no time",
"This cannot be true. It is not possible for a photon to have a rest reference frame in special relativity, because special relativity requires massless particles to move at c in ",
" reference frames. Please see my post here for a mor... | [
"as something approaches the speed of light, time, from its perspective slows down.",
"This is not correct. ",
"Lets say that you are on Earth and can watch a clock on a spaceship that is flying by. If the spaceship is travelling at a sufficiently large fraction of the speed of light, you would see its clock ti... |
[
"What would happen to light shined into a perfect box of mirrors?"
] | [
false
] | null | [
"Hi ImperialStarDestroyr thank you for submitting to ",
"/r/Askscience",
".",
" Please add flair to your post. ",
"Your post will be removed permanently if flair is not added within one hour. You can flair this post by replying to this message with your flair choice. It must be an exact match to one o... | [
"Physics"
] | [
"'Physics'"
] |
[
"How fast would I have to tear paper for it to burst into flames?"
] | [
false
] | null | [
"I don't believe you would ever (even in some idealized case) be able to ignite paper by tearing it. Do you have a specific source for why this might be possible?",
"Activities like metal cutting do cause ",
"potentially large temperature increases",
". This is because there is a lot of plastic deformation ha... | [
"The more paper you have, the more paper there is to burn. Tearing more paper does not concentrate the heat at all."
] | [
"There is nothing sophisticated going on with my example calculation. I was just going by the units and the knowledge that a fracture (or in this case tear) releases energy uniformly per unit length of the tear. ",
"But because energy is released per length of tear, tearing more paper doesn't mean more temperatur... |
[
"Why do patterns form with a laser and diffraction grate?"
] | [
false
] | [deleted] | [
"I'm pretty sure what you have here is two 2D diffraction gratings stacked upon each other. When the dots go in and out of focus, the person is only rotating one grating relative to another. That's how the person produces the different diffraction patterns. If you want to learn how diffraction works/diffraction gra... | [
"No, it looks like he is rotating ",
"one of two diffraction gratings",
"."
] | [
"Looks like he uses a kaleidoscope and not a refraction grate."
] |
[
"Why haven't we been able to analyze samples of different foods to find out exactly what the ingredients are and the percent of each ingredient in the food? You know, to unlock the mysteries of Coca-Cola, Big Mac sauce, etc."
] | [
false
] | Or does this technology already exist? If so, how can these "top secret" recipes still remain secret? | [
"We can do this. We can tell you exactly what chemicals are in any particular food. The problem is, if you're attempting to replicate a \"secret recipe\" is that most of these chemicals will be complicated organic molecules, so we can't exactly reconstruct from scratch by adding chemicals to a vat because it'd be p... | [
"We'd need to get someone who's an expert in organic chemistry to give a definitive answer, but I'll try to give an example:",
"Let's look at beer. Let's say we wanted to figure out how to make beer, and we decide to do this by using mass spectrometry (which'll let us see the exact chemical makeup of the beer). T... | [
"You must also consider marketing when talking about why these \"top secret\" recipes exist. Is McDonald's going to be dethroned by some random mom and pop burger joint if they suddenly figure out how to make Big Mac sauce? Probably not. Does the allure of a secret sauce, that no one else can create, give more reas... |
[
"Would a helium filled drumset sound higher in pitch or just not work?"
] | [
false
] | null | [
"Sometimes 'stupid' questions are the best questions! ",
"It would depend on the pressure of the helium in the drumset. When something like a guitar string or a drum-skin oscillate, there's a restoring force pushing/pulling it back. The ",
"speed of the wave",
" depends on this restoring force. If you changed... | [
"Yes, in this case (again assuming no differences in pressure), the wavelength of the oscillation is the same, but the speed of sound in helium is faster than in air. Since:",
"c = λ x f\n",
"An increase in the wavespeed, for a constant wavelength, results in an increased frequency.",
"This would be a lot... | [
"Silicone sealant may seem scary to use in this situation, but it could work well to seal the head and the rim, and it's not bad to remove on polished surfaces and metals (caveats - time consuming because of the little bits that get left behind, and some silicone sealants release acetic acid - possibly corrosive). ... |
[
"Why do bats make such good reservoirs for zoonotic viruses?"
] | [
false
] | null | [
"The main factor is that they are extremely social, living in colonies with millions of individuals while also traveling long distances and interacting with other colonies. They move back forth between colonies picking up and passing around diseases giving them a lot of opportunity to evolve. ",
"Pig pathogens ar... | [
"A big part is their body temp, I recall. They may display fewer symptoms, and thus incubate better, because of their higher body temp.",
"\"Bats—the only flying mammal—display several additional features that are unique among mammals, such as a long lifespan relative to body size, a low rate of tumorigenesis and... | [
"Bats are the only powered-flight mammal and as consequence their muscles are in a constant state of damage. That muscle damage would provoke a constant state of inflammation however bats have evolved an immune system that has a much more toned toned inflammation response (as compared to ours) and a heightened inna... |
[
"When an electron and a proton come together, the electron orbits the proton forming a hydrogen atom. What prevents the electron and proton from just sticking together? Why is an orbit formed?"
] | [
false
] | Thanks in advance. | [
"The radius of the proton is ~10",
" meters, so having the electron stick together with the proton requires it be localized to that volume. If you try to confine an electron to that much space, by the Heisenberg Uncertainty Principle, the RMS spread in its momentum is on the order of 100 MeV and it would quickly ... | [
"Yes, RMS is root mean square, sorry.",
"The wikipedia article you want to see is the one on the ",
"Heisenberg Uncertainty Principle",
"Also helpful would be ",
"http://en.wikipedia.org/wiki/Bohr_model",
"\nand ",
"http://en.wikipedia.org/wiki/Basic_concepts_of_quantum_mechanics",
"Your question is a... | [
"No, that Wiki article is completely unrelated. Read up on Heisenberg's uncertainty principle:",
"http://en.wikipedia.org/wiki/Uncertainty_principle",
"The basic idea is that on very small scales, where quantum mechanics comes into play, you can't know a particle's momentum and position exactly. If you say the ... |
[
"What do the other 3% of peer reviewed studies on Climate change say?"
] | [
false
] | I'm familiar with the stat that 97% of peer reviewed studies say humans contribute to climate change. What do the other 3% say? Is there anything to them? Always thought it would be valuable to read the other side, but I honestly can't track down the studies | [
"Most of them are objectively wrong in some way or another. There was a paper from a few years ago that went through a selection of the 2-3% (38 different papers to be precise) in an attempt to replicate their results and found that they suffer from a variety of flaws. ",
"Here is the paper",
" in question, and... | [
"Or to put it another way, that 3% is more about the imperfections of peer review than about real errors in climate change science."
] | [
"Sorta disagree. It's not the reviewers' job to fact-check and confirm the paper's data and results, but it absolutely is their job to point out the sort of serious procedural errors and invalid methodology that ",
"/u/CrustalTrudger",
" refers to."
] |
[
"In a random question of random number predictions (i.e. lottery drawing), is a set of consecutive numbers any less likely to occur than any other combination of numbers?"
] | [
false
] | null | [
"The set of possible outcomes in a choose k numbers from n possibilities lottery, is the set of subsets of size k from the set of n possibilities, i.e. n!/((n-k)!*k)!.",
"The set 1,2,3,4,5,6 is just as likely to be drawn as 12,32,33,40,49,52 for example.",
"However there are only a very small number of consecut... | [
"A ",
" set of numbers, say consecutive, is no less likely to randomly occur than any other particular number set.",
"Although in the lottery, it is less likely for ",
" consecutive set to occur, versus any nonconsecutive set. "
] | [
"But if you are picking lottery numbers, I think it's worth remembering that if 1,2,3,4,5,6 wins, the pot would be split between a huge number of smartasses."
] |
[
"What happens to food as you cook it?"
] | [
false
] | I know the answer is very different depending on what we're cooking. I'd like to ask about two different things, starches and meats. So let's say we pop bread into a toaster oven at 500F. In the beginning we'll get evaporation of water, then the browning reaction, then it turns black. What is the composition of the black stuff? If you let it go on long enough, will it become elemental carbon (with metal impurities)? Next, we're going to grill a steak. So we pop it on and the meat starts to sizzle. We have the Malliard reaction going on the outside of the meat and proteins breaking down and coagulating on the inside. Then it will start to char as well. I would believe that since the composition of meat is much heavier on amino acids, that the blackened end product would be completely different than the bread if you leave it on the grill till it's crispy black. What exactly would it be? | [
"I would like to recommend ",
"On Food and Cooking: The Science and Lore of the Kitchen",
" by Harold McGee to anyone interested in these type of questions or cooking in general. It describes in detail almost everything you'd want to know about the science behind various cooking processes. There's even a whole ... | [
"Much appreciated. So the blackened carbon, will it be a mass of network bonds like graphite or a mishmash of long chain molecules, polymers, and polyaromatics? I.E. will the stuff be relatively biologically inert or cancerous?"
] | [
"The real black stuff would be inert.",
"The stuff right below it could be nasty, it's hard to say, but generally stated, it's fine."
] |
[
"As photosynthesis requires light, why aren't plants black to absorb the full spectrum of light, instead of green which doesn't?"
] | [
false
] | I know that plants at the shrub layer in forests and jungles tend to be a darker green to make up for the fact that they receive less light, so how comes every plant doesn't do this then so that they could produce more food? Edit: Holy crap this is a lot of responses. Thanks so much! And yes I know that plants are green because they reflect green light, sorry for the confusing wording. | [
"A Black equivalent of Chlorophyll does exist - usually within Seaweed.",
"This is because most plant life would overheat and their enzymes would denature if they were to absorb all spectra of light - therefore green is the commonly used colour as it reflects mid-energy photons and absorbs high energy (blue) ligh... | [
"Also plants are generally limited more by CO2 availability then light, at least under full sun anyway. Thats why plants grow just fine in greenhouses with sun shades drawn to block a portion of the light, still getting all that they need."
] | [
"Generally limited by CO2 availability from the air. Still air will rapidly be depleted of CO2 around plants. This is why increasing CO2 in greenhouses under otherwise unlimited conditions (lots of light/lots of water) causes increased growth and can also increase plant heat tolerance.",
"Edit: Also why fans and ... |
[
"What traits we have from some of our ancestors; Neanderthals?"
] | [
false
] | [deleted] | [
"Neanderthals are not our ancestors. They share a common ancestor, and were contemporaneous with modern humans. ",
"(Now to go out of my field a little: Non-African modern human DNA may contain a small amount of \"pure\" Neanderthal DNA, but this research is too recent for speculation about noticeable shared trai... | [
"Well, it depends what you mean by \"ancestor\". The Neanderthal population does not comprise the majority ancestry of modern humans. But every living non-African human has individual ancestors that were Neanderthals."
] | [
"The way in which genotypes map to phenotypes (\"traits\") is really quite complex, and we're only just beginning to really work out how that all works. You may have learned in high school biology about ",
"Gregor Mendel an his pea plants",
", where one gene coded for one trait, but what we've been learning in ... |
[
"Does the body send signals to fat and muscle cells?"
] | [
false
] | How does a fat cell 'know' when to give up its stored energy? How does a muscle cell know when to grow? Does the body tell it with hormones or some such thing, or do the fat and muscle cells just follow some kind of rule set? Are there any drugs designed to instruct the cells to behave in desirable ways? | [
"Welcome to the wonderful world of Physiology my friend! Physiology is the study of how organisms function. Cells communicate in several different ways, most of which are chemical. There's a few ways that the body communicates with itself. ",
"Autocrine signals cause the cell secreting the chemical to undergo a c... | [
"There have and several have been successful. Obviously, you know about steroids. There have been some studies on leptin (it's the hormone that reduces the feeling of hunger), but nothing came of it. There really is no hormone that burns fat. Lipolysis Is stimulated by low blood sugar. I guess you could give someon... | [
"So has any research been done in making drugs mimic some of those signals, say to lose fat or build muscle. I guess steroids would be a muscle building hormone... but is there anything else?"
] |
[
"Is there a way to get an electrode connected to your nerves without tons of money?"
] | [
false
] | I'm very interested in implants and exploring possibilities of human nervous system, and I was wondering if it was possible to connect something to your nerves without specialized lab equipment and thousands of dollars or euros. | [
"I feel like you shouldn't be doing anything with anyone's nerves if you can't answer this question yourself...",
"That aside, elaborate on what the electrodes are meant to do? You can affect the nervous system by applying an electric shock, like in nerve conduction tests - and this doesn't require breaking the s... | [
"Your intuition is correct. I know a tiny bit about the design of such devices. ",
"The reason why it's ordinarily quite hard to electrocute yourself with a car battery is that dry skin acts as a pretty good insulator. But if you attach an electrode with conductive gel to it, then a car battery can kill you quite... | [
"Without tons of funding you want to go with an uninvasive system (such as EEG for cortical or EMG for afferent and neuro-muscular signals).",
"I am actually building a system from scratch for use in brain-computer interface application and would highly recommend it. I am merely a bachelor in cognitive neuroscie... |
[
"To what extent did sexual selection and self domestication contribute to the wide variety of human pigmentation?"
] | [
false
] | It seems like there is a lot of consensus that differences in skin pigmentation largely emerged as different groups of humans adapted to different climates with varying degrees of exposure to ultraviolet radiation. , for example, Nina Jablonski makes the connection between darker skin and more exposure to UV radiation. On the other hand, I've noticed that both domesticated dogs and cats also have a large variance in pigmentation (very notably, in eye color: ; ; ). And as anthropologists like to say, humans are also a domesticated species, having domesticated ourselves using culture and civilization over the last few thousand years. That makes three very interesting examples of domesticated animals with very notable variance in pigmentation. As far as I know, there are no other examples of large mammals where such a dramatic variance exists. Aside from this very interesting correlation, is there any evidence that suggests that domesticating factors like sexual selection played a role in the wide divergence in human appearance? Conversely, is this type of physical variance potentially a sign of domestication, and does the existence of such variance in humans give sway to the idea that humans are "domesticated"? | [
"http://www.sciencedirect.com/science/article/pii/S0047248400904032",
"This abstract suggests we have established a very obvious correlation between latitude/ sun exposure and the skin pigmentation of the local population of humans. It also suggests that such pigmentations are quite mutable and respond well to ch... | [
"Your question reminded me of this ",
"study",
" which made the ",
"news",
" a few years back. Xasrai is certainly right about the evolutionary advantages of light/dark skin in the regions they developed. However, this study suggest that sexual selection coupled with environmental factors(*which gave this... | [
"What about cultural preference to a certain race? Africans only marrying Africans and Japanese only marrying Japanese, for example. These are still prevalent and were even more so back in time. Couldn't you consider such practices a positive pressure to maintain the light (or dark) skin? ",
"In Europe, for exam... |
[
"Do different types of cells become what they are by turning on and off certain areas of a person's genetic code to therefore alter protein production?"
] | [
false
] | Is the difference between cells found only in the fact that they make different proteins? | [
"See ",
"Gene regulatory network",
".",
"Pretty god explanation there:",
"In multicellular animals the same principle has been put in the service of gene cascades that control body-shape.[2] Each time a cell divides, two cells result which, although they contain the same genome in full, can differ in which ... | [
"The breakthroughs in metabolic engineering usually come from biological discoveries and development of techniques. As far as achievements go, large portion of pharmaceuticals use at least one bioprocess, as they create enatiomerically pure products, which are required in drugs. Newer technologies include butanol... | [
"Thanks that's really helpful."
] |
[
"How and why does high blood volume/pressure pose a risk to health?"
] | [
false
] | Hi there. I am looking to understand how high blood pressure or high blood volume alone (with no atherosclerosis or other signs of CVD) can damage health. I am interested in the specific physiological mechanisms (if any) through which chronic high blood pressure damages any part of the human body. Thank you! | [
"There isn't one specific answer to this, but from the hearts perspective: High blood pressure increases what we refer to as afterload, which is essentially the force that must be overcome by the heart to open the aortic valve and eject the blood from the ventricle. ",
"In simplified terms: Higher afterload means... | [
"Full understanding of this topic probably requires you to do some reading. See ",
"http://cvphysiology.com/",
" if you're interested. In short: it's not a desirable state long term but under physiological conditions your blood pressure spikes as a consequence of increased cardiac output in an attempt to increa... | [
"High blood pressure is a relatively recent phenomenon in humans. Mechanisms that maintain lower limits of blood pressure have been well conserved through evolution and it’s easy to understand why. Loss of blood, sudden and short bursts of high intensity activity, and other events that occur in nature require dynam... |
[
"Why is it that I can safely eat a rare steak but eating undercooked chicken, fish, or pork could land me in the hospital?"
] | [
false
] | null | [
"Actually fish can be eaten raw, ever heard of sushi?",
"Pork can also can now be eaten undercooked but it doesn't taste that much better. The main problem used to be a parasite (",
"http://en.wikipedia.org/wiki/Trichinosis",
") which has been pretty much eradicated.",
"The only bad one is chicken, which ca... | [
"Only in the US. All eggs are processed in such a way as to remove the outer membrane, allowing bacteria (salmonella?) to penetrate the shell, which is actually semi-permeable. ",
"Raw eggs in other countries are much safer.",
"A Forbes article on the topic",
"efraim lower down in the thread."
] | [
"Eggs are edible raw, but the eggshell has plenty of bacteria on it. If the shell comes in contact with the insides while cracking, it will need to be fully cooked."
] |
[
"How is 'sea level' measured?"
] | [
false
] | Also, why am I able to drive on a highway and have my GPS say I am 7 or 8 meters below sea level? Shouldn't that be covered by water? For what it's worth, I am located and drive throughout New Brunswick Canada, very near the coast. | [
"That makes sense. The areas I'm referring to being below sea level are directly on the coast. ",
"This area",
" for instance reads as -7m below sea level from my truck's dash. It's directly on the coast so the sea water wouldn't have to climb over top of anything to fill this area in. ",
"I suspect that my u... | [
"That makes sense. The areas I'm referring to being below sea level are directly on the coast. ",
"This area",
" for instance reads as -7m below sea level from my truck's dash. It's directly on the coast so the sea water wouldn't have to climb over top of anything to fill this area in. ",
"I suspect that my u... | [
"GPS altitudes are in reference to the ",
"World Geodetic System",
", which is an oblate spheroid (squished sphere) centered at the Earth's center of mass. Its measure of sea level incorporates corrections for variations in the Earths gravitational field, but still doesn't always line up with the actual mean le... |
[
"Are women emotional and men rational ?"
] | [
false
] | null | [
"Thank you for your submission! Unfortunately, your submission has been removed for the following reason(s):",
"We do not debunk or vet theories or offer peer review on ",
"/r/AskScience",
". For more information regarding this and similar issues, please see our ",
"guidelines",
"\"Hysteria\" and similar... | [
"I was citing hysteria as an example of how psychologists can be wrong. Hence I wanted to know if there was a biological consensus on the stereotype"
] | [
"As I pointed out, we don't address such stereotypes or try to debunk baseless sexist ideas"
] |
[
"Additions to Highschool curriculum in the last 10 years?"
] | [
false
] | null | [
"Physics"
] | [
"Physics"
] | [
"Thank you for your submission! Unfortunately, your submission has been removed for the following reason(s):",
"A good home for this question is our sister subreddit ",
"/r/AskScienceDiscussion",
" because of its open-ended or speculative nature. Please feel free to repost there!",
"Please see our ",
"gui... |
[
"Is laughing instinctual for humans, are animals capable of laughing too?"
] | [
false
] | Why, physiologically and psychologically, do humans sometimes have the overwhelming urge to laugh? What is happening in our brains? Why do we all do it in the same way (roughly). And are animals capable of laughing, or synthesizing humor (or whatever is the external force causing us to laugh)? | [
"The results of this study indicated that chimpanzees produce ",
" that is distinct in form and occurrence from their ",
". These findings provide the first empirical evidence that nonhuman primates have the ability to replicate the expressions of others by producing expressions that differ in their underlying ... | [
"Rats laugh when you tickle them"
] | [
"Rats giggle when tickled!!",
"http://www.youtube.com/watch?v=j-admRGFVNM&feature=youtube_gdata_player"
] |
[
"Is the event horizon of a black hole a 3D globe, or a 2D ring?"
] | [
false
] | I understand all black holes shown in publications are just simple examples, there are no real pictures. But saying that, what do the leading theories say about the real shape? Is it a black ball or more like a whirlpool vortex? Is it more like an ice cream , the pointy end is the singularity and the open end the event horizon? | [
"The black hole event horizon is a spherical surface surrounding the matter inside of the black hole. The radius of the sphere is given by the ",
"Schwarzschild radius",
", or the radius within which the ",
"escape velocity",
" is equivalent to the ",
"speed of light",
"."
] | [
"The event horizon is perfectly spherical for a non-rotating black hole, but for a rotating black hole it will be somewhat oblate."
] | [
"I'd imagine most black holes are rotating? Or is rotation rare?"
] |
[
"Once a rocket reaches space and goes in to free fall, how do they get fuel/oxidant to flow downward towards the nozzle without thrust or gravity pulling it downward?"
] | [
false
] | There has to be some simple mechanism that pushes the fuel and oxidant out of the fuel tanks once they've cut their initial thrust. What is it? | [
"In the simplest tank design, the propellant is at the bottom, separated by a diaphragm from an ullage volume where a pressurizing gas pushes the diaphragm.",
"Pros: very simple and cheap design",
"Cons: you lose pressure as the propellant is consumed and the gas expands on an every time larger volume. This can... | [
"You can either use an inert gas to pressurize your tank and push the propellant towards the engines or you can bump the rocket with something like a cold gas thruster or a small ullage motor to get all the propellant to flow to the bottom just prior to ignition."
] | [
"The third stage of the Saturn V used ullage rockets. It only had to relight once, so it had four small solid rocket motors that would give it a kick forward to force the propellants to the \"bottom\" of their tanks so that they could properly feed the turbopumps. Once the engine's lit, you're good to go.",
"Afte... |
[
"We are scientists from the Society of Vertebrate Paleontology coming to you from our annual meeting in Toronto, Canada! We study fossils. Ask Us Anything!"
] | [
false
] | We are scientists from the Society of Vertebrate Paleontology coming to you from our annual meeting in Toronto, Canada! We study fossils. Ask Us Anything! Hi ! We are members of the , here for our 9th annual AMA. We study fossil fish, mammals, amphibians, and reptiles — anything with a backbone! Our research includes how these organisms lived, how they were affected by environmental change like a changing climate, how they're related, and much more. You can . Joining us today are: ( ) is the Curator of Palaeontology at the Royal BC Museum in Victoria, BC. Her primary area of research is on the dinosaur group Ankylosauria, including their evolutionary relationships (phylogenetics) and the biomechanics of their tail clubs. You can read more on Dr. Arbour’s website at ( ) is the Curator of Fossils at the at Duke University in Durham, NC. His research focuses on the evolution of carnivorous mammals and primates, especially in Africa and North America. He is also part of several teams working to network natural history collections. Dr. Borths co-produced the paleontology podcast series Past Time ( ). ( ) is the Curator of the North Dakota State Fossil Collection and the Paleontology Program Manager for the North Dakota Geological Survey. His research focuses on the evolutionary history of ornithischian dinosaurs and studying Eocene and Oligocene faunae from the Great Plains region of North America. Find him on twitter @boydpaleo. ( ) is a paleontologist at the University of Tennessee whose research focuses on the processes of fossilization, evolution, and biology, of crocodiles and their relatives, including identifying bite marks on fossils. Find her on Twitter @UglyFossils. ( ) is a fossil preparator with the State Historical Society of North Dakota. She has cleaned and repaired many fossil specimens for public museums and institutions over the past 18 years. Some well known specimens she worked on include “Jane” the juvenile Tyrannosaurus rex and “Dakota” the Edmontosaurus sp. fossilized natural mummy. ( ) is a paleoecologist and Assistant Professor at the University of Cincinnati. His research focuses on Pleistocene paleoecology, taphonomy, and using fossil and subfossil records to help conserve and manage modern ecosystems (Conservation Paleobiology). Find out more at JoshuaHMiller.com. ( ) is an ecologist who works on landscape-level modeling of coastal and wetland ecosystems. She also studies the morphology and ecology of fossil and modern crocodylians, and uses quantitative methods to inform conservation decisions. ( ) is an early career paleontologist and Assistant Curator of Geology at the Illinois State Museum in Springfield, IL USA. Her research focus is paleoecology of Quaternary mammals, including their diets and geographic distributions. ( ) is the Assistant Curator of Paleontology at the Virginia Museum of Natural History in Martinsville, VA. His research focuses on the evolution of reptiles during the Permian and Triassic periods, a time of great change that saw the rise of the dinosaurs. Please check out the Virginia Museum of Natural History at vmnh.net. Dr. Pritchard has also co-produced the paleontology podcast series Past Time, available at . ( ) is the Director of Visitor Engagement and Education at the Raymond M. Alf Museum of Paleontology in Los Angeles, California. His previous work focused on the paleontology of Southern California, particularly the evolution of marine mammals. Today, his research has shifted to education and DEI in STEM as a National Geographic certified educator and cofounder of the Cosplay for Science Initiative. He was recently named a Grosvenor Teacher Fellow with National Geographic and Lindblad Expeditions. You can find him online as @paleoparadox. | [
"There have been so many really incredibly preserved fossils out there, ranging from single cells preserved in the act of division to mummies of whole mammoths (like this ",
"recently discovered baby",
"). And while it is awe-inspiring and exciting to be able to study the ",
"mother's milk",
" from the stom... | [
"Which is the best preserved fossil ever discovered that gave a lot of information? More than any other fossil of it's kind has."
] | [
"Usually, we start by just walking around and looking for fossils coming out of the ground. After finding something interesting, we work to carefully remove the rock around a particular fossil. If there seems to be a lot of material still buried under the rock, that may be a good place to start setting up a formal ... |
[
"If chronically high cortisol levels can eventually lead to cancer, and cannabis raises cortisol, can marijuana actually contribute to cancer risk?"
] | [
false
] | null | [
"Cortisol may lead to cancer because it's an immunosuppresant on T cell, which (among other thing) survey your body for precancerous cells. It can also lead to central obesity (back hump, etc) because cortisol is one way for your body to regulate fat accumulation.\nI'm not sure how cannabis might raise cortisol lev... | [
"Here",
" is a study (full free article) you may have come across before, but it states this as the results in the abstract: \"At socially relevant doses, Delta-9-THC raised plasma cortisol levels in a dose-dependent manner but frequent users showed blunted increases relative to healthy controls.\" It is interest... | [
"Can you cite where you read that cannabis increases cortisol levels?"
] |
[
"Aerodynamics Application"
] | [
false
] | If dimples help golf balls fly better, why don't we put dimples on our cars' exteriors? Are there any motor companies that have researched this? The MythBusters tried it a while ago and reported an 11% increase in efficiency. Needless to say, their testing is less than rigorous. | [
"Golf balls are spherical; and with dimples on them, they are begging to be spun in the air. The dimples increase the range of flight for the golf ball because of lift (and low air drag because of no flow separation). A car with dimples on it would be similar to a car with a spoiler on the back end. A spoiler serve... | [
"As an example of why spoilers are (in some cases) necessary, you can take a look at ",
" testing the Koenigsegg CCX",
"."
] | [
"thank you, that is very interesting. ",
"I particularly liked the flow visualization around the vehicle."
] |
[
"How do central banks determine exchange rate targets?"
] | [
false
] | [deleted] | [
"Hi there,",
"This is somehow out of my area of study, but I see it non the less as an interesting one. I would however suggest that you narrow it down as it is very broad now. I'd suggest that you break out the questions into separate ones as, as it is now it is in my opinion to wide to properly be answered here... | [
"So first of all most central banks do not have explicit targets - the US government does not for example nor the British though they will view the currency as being over/under valued at certain levels.",
"So the exchange rate is actually set by the markets - by where trades actually happen and there is a feedbac... | [
"Well I understand that most currencies float (or like RMB partial float), but like you said \"they will view the currency as being over/under valued at certain levels.\" What makes them think one way or another? Does it really come down to \"public sentiment\"? Do they not have their own thoughts on what is 'good'... |
[
"How does the International Space Station regulate its temperature?"
] | [
false
] | If there were one or two people on the ISS, their bodies would generate a lot of heat. Given that the ISS is surrounded by a (near) vacuum, how does it get rid of this heat so that the temperature on the ISS is comfortable? | [
"Hey I worked on the ISS thermal control systems. The station is essentially cooled by a water cooler like you see in high end PCs. All of the computers and systems are on cold plates where heat is transferred into water. This is necessary because without gravity air cooling doesn’t work well. The warmed water is p... | [
"Water would freeze if it was pumped through the space-side radiators. Ammonia can stay liquid down to -107F (-77C) and so can be pumped through the radiators without freezing and blocking them. "
] | [
"It is honestly an awful potato of a photo to show the panels. Here's a better view (the white fold-out panels): ",
"https://i.stack.imgur.com/cpIBo.jpg"
] |
[
"When under anaesthetic for surgery or else, if a doctor holds open your eyelid, is the brain still registering sight or have your eyes 'shut down'?"
] | [
false
] | Edit: Just to clarify, I had this thought today because I wondered what it would be like if I ever had to have surgery on one of my eyes. I'll be damned if I'm letting them anyway near either of them when I'm conscious or aware, but then I thought 'well they're going to be holding my eye open anyway, how much of that will register?' | [
"Yes your brain would respond. There is a great deal of literature on perception and visual perception in particular. The cells of the early visual cortex will respond to any signal coming from the retina. Including when the subject is unconscious. They have done this exact experiment with single-unit recording in ... | [
"There's a little more to the story. Many studies of visual function (e.g. Hubel and Wiesel) were/are done in ",
" animals. Yes, they were prepped under anesthesia, but anesthesia was discontinued prior to recording (whether such experiments are ethical is a question for another time).",
"As a rule, anesthesia ... | [
"There are lots of classes of anesthetics. I'm speaking in regards to barbiturates, like Amytal. These drugs depress central nervous system response. So in a sense, the eyes are not \"shut off\", in the sense that your eyes are getting input, its just that the brain isn't being stimulated nearly as much, if at all.... |
[
"Why are most opera singer's a bit overweight? Is there a correlation between body volume and vocal abilities?"
] | [
false
] | null | [
"Her costume is also the reason Vikings are depicted with horned helmets these days. That originated with one production of the Ring Cycle or other."
] | [
"Her costume is also the reason Vikings are depicted with horned helmets these days. That originated with one production of the Ring Cycle or other."
] | [
"What about Pavorratti (sp), or Placido Domingo? Both are large guys, did their body size correspond to their ability to reverberate?"
] |
[
"Can bacteria orbit a bowling ball ?"
] | [
false
] | Can somthing really small but still not in the subatomical scale like say bacteria orbit around somthing big like a bowling ball or a 10 meter diameter steel ball ? | [
"Strictly speaking, anything can orbit around anything. If M is the mass of the central object, and r is the radius of the orbit then the orbital speed must be sqrt(GM/r) where G is the gravitational constant, which is about 10",
" in SI units. So you can see that the only way to really achieve an orbit in humanl... | [
"If all that's in the universe is the bacterium and the bowling ball, then the bacterium will orbit the ball.",
"In reality though there's other stuff. The bowling ball is itself orbiting something. The ball will have a sphere of influence, a region of space around it in which small objects will orbit the ball. O... | [
"In 1827, Robert Brown notice, through his microscope, pollen grains in water jumping randomly around. This is called [Brownian motion]",
"https://en.m.wikipedia.org/wiki/Brownian_motion",
"). Albert Einstein won a Nobel Prize by showing this movement is caused by water molecules hitting the pollen. ",
"Bacte... |
[
"Does dark matter and dark energy also exist on Earth or only in space?"
] | [
false
] | Is there dark matter in our atmosphere surrounding us right now? If not, where is it found? As close as our orbit or way farther out in space? | [
"Dark energy is associated with space itself, so it is literally everywhere, with the same amount being found at each point. However, within galaxies there is enough matter that gravity wins out over the expansion caused by dark energy, so while it's still there, we don't notice its effects.",
"Dark matter is ins... | [
"It relies on the statement that dark and luminous matter don't interact being almost, but not quite true. If rare interactions can occur, a collision within the Sun could take away energy from the dark matter particle and allow it to get trapped.",
"There's also attempts to directly detect dark matter passing th... | [
"That doesn't mean we can't accurately constrain what their properties need to be, thanks to the huge amount of indirect evidence we have. Rather than rehash it, I'll point you to ",
"this excellent comment",
" which summarises why dark matter remains the leading hypothesis.",
"Many laypeople seem to want to ... |
[
"Do hair products \"kill\" your hair?"
] | [
false
] | null | [
"Hair is already dead, so what exactly do you mean by kill? Do you mean cause baldness, cause breakage, etc? Repost this question with your definition of kill. :)"
] | [
"Ah, I see how I mislead people. Sorry for that. Well this one type of pomade was thining out my hair. My relatives and some friends said if I keep using it my hairline would start to receed and soon become bald. Is that true?"
] | [
"Post a new question that asks just that. We can't definitively tell you that is what is occurring, but if you asked a ",
" question you may get some answers. A good way to ask would be, \"Is it possible that a hair product such a pomade made with x, y, and z could cause balding / hair loss?\" ",
"Just keep any... |
[
"Pet question, details inside! (sorry if this is in the wrong subreddit, I tried looking for a more suitable one)"
] | [
false
] | null | [
"This isn't a place for veterinary advice..."
] | [
"I disagree ಠ_ಠ",
"That's why I'm here.",
"OK edit not this type of question. I'll leave the post removed and answer it personally."
] | [
"I'm really sorry but I tend to agree with bobtentpeg that this isn't the right subreddit for this type of question as it's not about science but more asking for personal veterinary advice. Unfortunately I'm not sure I have a good recommendation for another subreddit, however one of our other mods is a vet and the... |
[
"Can the heart actually \"skip a beat\"?"
] | [
false
] | When people get surprised or scared, a lot of them will say, "My heart just skipped a beat!" Is there any truth to this, or is it just an expression? | [
"So there's actually two parts to this question: 1) are there sometimes heart rhythms where there is beat missing? and 2) what happens you are startled?",
"1) Are there sometimes heart rhythms where there is beat missing? ",
"Yes! There are many types of arrhythmias that involve a dropped beat. The most inoccuo... | [
"What about anxiety-related palpitations? They seem to fall partially in both categories, based on this description."
] | [
"Wow! I didn't realize that there was quite that much going on. Great answer, thank you!"
] |
[
"Why can't we take pills that deliver all the needed nutrition to our bodies instead of consuming food?"
] | [
false
] | This may be a rather obvious question, but I was thinking the other day: Is there something preventing a person to stop eating food all together and just consume pills that contain all the needed nutrients to fuel the body for a single day (or even longer)? Would there be drawbacks from doing something like this? | [
"Assuming you package the most dense food source (fat) into pills, you would need to swallow about 250 large pills per day to meet your energy requirements, if you add an adequate amount of protein to your diet, that number increases to around 400 pills."
] | [
"Sorry if this is not scientific enough as an answer, but it's basically because nutritional science is shaky at best. For a very long time, Fats in all forms were vilified, until we figured out that some fats were good. We found a new bad guy in carbs, but that is proving to be less and less true as well. I sugges... | [
"The largest capsule size on the market designed for human consumption is size \"000\", which holds 1.37 ml. If you fill them with pure oil, that is 11 calories per pill, a pill of equal size full of protein would have 5 calories at most. \nAssuming a 2000 calorie daily energy requirement, and 56 grams of protein, ... |
[
"Why do Africans have the hair they do? And why does almost everyone else have straighter hair?"
] | [
false
] | null | [
"Most sources I've found suggest it helps keep the head (importantly, the brain) cool and protected from the sun.",
"Straight from ",
"Wikipedia",
":",
"Jablonski[36] asserts that it was evolutionarily advantageous for pre-humans to retain the hair on their heads in order to protect the scalp as they walked... | [
"So you're saying there are two conflicting schools of thought on this issue?"
] | [
"There are assertions like Jablonski's and critiques of those assertions. I haven't found any other suggestions."
] |
[
"How is it determined which direction objects in space will spin?"
] | [
false
] | Thought about this while watching the toilet water go down the bowl and remembered how in the southern hemisphere he goes counterclockwise. Is there anything that determines which direction things like galaxies, black holes and planets turn ? | [
"water in your toilet does not spin the other direction in the southern hemisphere. ",
"The direction your toilet flushes is 100% defined by the way it was designed. ",
"Coriolis force only acts appreciably on large areas or high velocities while \"on\" the surface of a spinning object (planet, merrry-go-round,... | [
"More or less at random. Take a star, for example. It forms from a cloud of gas floating out in the galaxy, when that cloud collapses under its own gravity. But all the different parts of the cloud have slightly different velocities, so the velocities that they have relative to the center of mass will induce some s... | [
"Though toilets typically have jets that determine their direction, the coriolis force can matter if you have a large pool of water that contracts inward without other rotational forces. If you take a motionless meter wide pool of water and let it drain through a small hole, it will eventually start spinning in the... |
[
"Why is fuel on space vehicles often stored in spherical vessels?"
] | [
false
] | A good example: I realize that this probably does not hold true for all types of fuel, but what types of fuel stored like this, and why? Why not use cylinders, or other shapes that better fit the form of the space in which the vessel is located? Wouldn't it be a more efficient use of space? Also, I realize that a number of the vessels pictured may be compressed gases for life support or verniers, but my question in these cases still stands. | [
"Here's",
" a better picture of the tanks.",
"I wasn't a design engineer on the program, so I can't say for certain, but I think these are used because they are the most efficient use of weight, which is much, much more precious a commodity than volume when we're talking about putting something into LEO.",
"A... | [
"The stresses in the wall of a spherical pressure vessel are lower than in (for example) a cylindrical vessel, by a factor of two. There is a discussion ",
"here",
". So the walls of the spherical vessel can be half as thick as those of a cylinder, for the same pressure, for the same material."
] | [
"Yeah, I'd say it's likely entirely because of weight, with the added bonus that's it's also the strongest, and least surface area to worry about insulation issues.",
"I believe those are cryogenic tanks too, meaning they're probably at very high pressure, and need to be kept well insulated."
] |
[
"How much of the temperature on earth can be attributed to geothermal heat from the mantle and core etc?"
] | [
false
] | null | [
"Essentially none, unless you're sitting on a hot spring or fumarole over a tectonic rift or hot spot. Check out figure 1 here--extreme values of mantle heat flow are around 0.5 Watts per meter squared. By contrast, solar radiation is on the order of 1000 W/m",
" (depending on season and latitude). That means tha... | [
"Check out figure 1 here",
"...you didn't link anything."
] | [
"Not quite none. More like 40 K. So solid nitrogen and solid oxygen and dry ice, liquid hydrogen, and still gaseous helium. And while the surface of the oceans would obviously freeze over, they'd serve as a pretty good insulator to keep much it the rest liquid underneath."
] |
[
"When it is crazy cold in the U.S. does that mean that the globe is likely colder overall at the moment, or is the distribution of cold and warm on the planet just distributed differently?"
] | [
false
] | null | [
"You basically can't infer anything that specific from a single event. That's the whole essence of the difference between weather and climate; at any single moment the weather in one place doesn't tell you a whole lot that is useful about the weather somewhere else. Only over time can you identify any kind of patte... | [
"For convenience"
] | [
"No, Antarctica is warmer than the average for Antarctica this time of year. Ohio is colder than the average for Ohio this time of year. ",
"Those maps are about deviation from the average, not absolute temperatures. "
] |
[
"How does sickle cell anemia grant resistance against malaria?"
] | [
false
] | I know it does, but it didn't come up during a recent series of lectures in my parasite biology class. I know about the life cycle of and PfEMP1 if that makes it easier to explain. | [
"Sickle cells have a lower oxygen carrying capacity. This causes the malaria parasites to suffocate in the blood. But a side effect of Sickle cell anemia is shortness of breath because your blood can't carry quite enough oxygen "
] | [
"You see it a lot in Africans because malaria is a big problem over there. Sickle cell anemia is actually an evolutionary defense mechanism "
] | [
"I didn't expect it to be so simple. Thank you for answering."
] |
[
"I have a question about the James Webb Space Telescope"
] | [
false
] | More specifically on it's ability to see 13.4 billion years into the past. I understand the principle ( light particles travel fast but not infinitely fast, and the further the object the longer it would have taken the particle to reach us, thus the what we see is actually the "past version" of the object) But I have trouble representing myself this, and the theory that the universe is ever expanding together. How can we see something that dates from an "epoch" where the entire universe was smaller? I'm sorry I can't phrase this better. | [
"This is actually a very subtle question you've asked here.",
"How do we define \"distance?\" Oh, well, that's easy. It's that thing you measure with a ruler.",
"But there's an unspoken assumption beneath that: that the two things you want to measure the distance between are ",
"Say a bird lands a branch of a... | [
"All* the protons, neutrons, and electrons in your body come from an epoch when the universe was smaller (much, much smaller). What's so crazy about finding photons that have done the same?",
"*Basically all, at any rate."
] | [
"I don't think this was the question the OP had - photons are going to stick around for a while if they don't interact with anything. Rather, I think OP was asking, \"\"If photons come from a time when the universe was smaller, why haven't they arrived yet?\" I think that there are several incorrect hypotheses th... |
[
"Is there a chemical reason why elements change properties when forming compounds? (ex. sodium and chloride losing explosive and poisonous properties when forming table salt.)"
] | [
false
] | Something I have always wondered and just discovered this wonderful subreddit to ask it in. A quick google search did not offer me anything, I'd appreciate any help! | [
"It's all about electrons...atoms with incomplete shells react with others in a way that allows it to complete the outer shell. Atoms react to give up, receive, or share electrons to produce a completed outer shell.",
"Atoms with a complete outer shell do not react with other atoms. ",
"See diagrams at:\n "... | [
"Atoms love to have completed electron shells. The inert gases? The outer electron shell is complete, so they are almost totally unreactive. They are at peace. ",
"In the periodic table, sodium is one further along than neon, an inert gas. Therefore, it has one lonely electron in the next shell, and it's very rea... | [
"A lot of chemistry and physical properties come from the way electrons are arranged in molecules. Electrons can be shared or exchanged to form bonds, electron clouds may be denser around different parts of the molecule, they could be moving between states of high or low energy. When a reaction happens, the configu... |
[
"Orientation in space?"
] | [
false
] | Might be a stupid question but planets in space don't neatly align horizontally do they? Are some planets higher or lower then others? Do you go up or down to get to other planets, how does it work? | [
"The planets in our solar system are all approximately on the same horizontal plane. The ",
"wikipedia page",
" provides a table of the different orbital angles/inclinations of planets.",
"Other planetary systems are aligned on different planes, there is nothing special about our orbital plane."
] | [
"What you are asking about is called \"inclination\". Some planets have more inclined orbits than earth and in order to go there you need to perform an inclination change, which in layman's terms might be considered \"going up or down\".",
"http://en.wikipedia.org/wiki/Orbital_inclination_change"
] | [
"Yes, the planets do not neatly align in space. Here's why:\nConsider the equator of our sun. The plane of this (sun's) equator is called the ecliptic plane. \nNow consider the planetary orbits around the sun. Each planet's orbit can be tilted in any orientation from any point (think of a plate that you're balancin... |
[
"ALTERNATE REALITY: Could Modern Scientific/Medical Understandings Have Been Discovered In The Past?"
] | [
false
] | null | [
"Thank you for your submission! Unfortunately, your submission has been removed for the following reason(s):",
"guidelines.",
"If you disagree with this decision, please send a ",
"message to the moderators."
] | [
"I understand, can you suggest a thread under which I may post this?"
] | [
"r/asksciencediscussion",
" could be a good fit."
] |
[
"Can Brownian motion be considered an application of chaos theory ?"
] | [
false
] | Chaos theory applies to systems highly sensitive to initial conditions. In the (highly unlikely) situation where we know everything about every particle (for exemple, in the case of a computer simulation), can Brownian motion, a typical stochastic process, be considered an application of chaos theory ? | [
"Semantically no, but practically yes.",
"The distinction between chaotic systems and stochastic systems is that the latter is assumed to depend on variables that cannot in principle be known. Brownian motion is usually considered to be stochastic, and if we know the initial conditions it's probably not proper to... | [
"I don't see how it would be very useful to think of Brownian motion in that way. At the fundamental level, Brownian motion is an example or 'application' of the ",
"Fluctuation-Dissipation Theorem",
". Its only necessary to have a system with many degrees of freedom in thermal equilibrium, and most often restr... | [
"Really clear and concise answer ! Thank you very much !"
] |
[
"Some questions about airloy aerogel, a strong ultralight nanoporous material with remarkable insulating properties."
] | [
false
] | How much heat can it withstand? Could you build pottery kilns out of it? Is it toxic? Does it decay or fall apart over time? It seems to me that this is a wonder-material. Why is it not manufactured on a mass scale for common use (in house insulation, in ovens and other appliances and machines, in battery casings, etc)? Is the cost of manufacture especially prohibitive? Is it simply not as useful as I imagine it is? | [
"How much heat can it withstand? Could you build pottery kilns out of it?",
"less than bulk silica, the high surface area makes it start to soften and deform relatively easy. You could use it as insulation but it would not be a good first wall material as it would melt and deform.",
"Is it toxic? ",
"No it i... | [
"Primarily silica based gels as those are the most common.",
"Any material with that high of a surface area will be pretty unstable at high temperature. Fine grained structured have an extra inherent energy because of their small size, high surface areas and highly defective structures. This energy reduces temper... | [
"Aerogels are pretty expensive to manufacture, so that limits them to applications where the thermal performance justifies the cost. If you go to the website mentioned in the YouTube comment, they sell a 50x75x7mm slice of this stuff for $90. That's about 1,000,000 times as expensive as styrofoam."
] |
[
"If Earth was a perfect sphere, how deep would the water be?"
] | [
false
] | I'm asking because theoretically a perfect sphere would mean Earths water would be spread evenly everywhere. I guess I'm also curious about how much water is on Earth? Is there a guess as to how much water is held in the atmosphere and on the polar caps? | [
"Wolfram|Alpha",
" gives the volume of water as 1.386x10",
" km",
" . I'm working on an integral using the ",
"radius",
" of the earth (given by Google) now to solve the depth, but I feel like I won't have enough time.",
"Here are my results: I didn't need the integral except to think about it, but the ... | [
"For such small depths compared to the size of the Earth you'll only need the surface area of the Earth and the total volume of water for a very good estimate. Indeed, my calculations agree with yours (given that the estimate from WolframAlpha is right)."
] | [
"Regarding amounts ",
"here are the numbers",
"... almost all is in the oceans (97.5%), very little in the atmosphere (0.001%). The ",
"water on land is mainly in the ice caps of Antarctica and Greenland, the rest in the ground",
"."
] |
[
"Would replacing a transmission with an electric generator, and placing electric motors at each wheel be more efficient than current vehicles?"
] | [
false
] | null | [
"But without needing a variable about of torque you can use a turbine engine that is upto 60% efficient",
"so it's actually 0.6*.8 *.885 = 0.4248",
"and 0.4248 is more then .34",
"This is the main advantage of why serial hybrids are so promising. "
] | [
"Efficiency of Internal combustion engine 37%(1)\nEfficiency of Vehicle Mounted Electric Generator 80%(2)\nEfficeincy of electric motor 88.5 (3) (I chose the 20-49 HP motor as you would have one on each wheel giving you upto 196HP for your car).",
".37 *.8 *.88.5 = 0.262.",
"37% down to 26% is approximately a t... | [
"A car converts chemical potential energy of the fuel directly into rotational motion of the wheels. A gas/electric generator converts chemical potential into rotational motion, into electricity, and then you would convert this electricity back to rotational energy in the wheels. I don't know how exactly how effi... |
[
"Any mycologists here? What is growing on my lawn?"
] | [
false
] | While mowing the lawn this morning, I noticed what I thought were multiple presents from a neighbor's sick dog. However, when I picked up the substance with a plastic bag, it disintegrated into a fine dark powder. Since I probably inhaled some of it, I thought I'd take it to my pathology lab and see if I could figure out what it is. (It's just a wet mount without stains. Best I can do with the equipment I have.) I live in the desert southwest, by the way, so is a concern. A Google search for what these fungi look like in nature was not fruitful, but the size of these elements isn't too dissimilar from the spherules and endospores that I see in coccidioidomycosis in the lungs. | [
"That looks like ",
"Fuligo septica",
", AKA the dog vomit slime mold. That's it's real common name, which probably doesn't surprise you much. :D"
] | [
"I would recommend cross posting this to ",
"r/mycology",
" as well, they have a fairly active community. "
] | [
"Thanks for the heads up. I should have figured there would be an ",
"/r/mycology",
". :)"
] |
[
"Are blood bags usually sealed (in a vacuum)?"
] | [
false
] | I didn't know exactly where to post this, but I was calculating the pressure of blood coming from a blood bag for a physics problem and was curious to know if blood is normally stored in a vacuum (so no additional pressure from air). EDIT: Just to be clear, I don't mean a perfect vacuum of course, just enough that the increase in pressure is negligible. | [
"Being sealed and being in a vacuum have nothing to do with each other. A pure vacuum is an area in space with no matter. For practical applications, it's an area with almost no matter, meaning it has extremely low pressure. Blood in a sealed bag has a pressure, and that pressure is a sum of atmospheric pressure an... | [
"If you did put blood in a vacuum, it would boil (cold boiling) and loose water rapidly. Probably killing the blood cells from the ice forming from heat loss."
] | [
"I suppose they are not in fact vacuum sealed as you readily need to insert vacuum tubes into the bags to draw out the blood for use. If there was already and existing vacuum in the bags the blood would not be pulled out through the tubes. However, it is important that the inside of the bags remain closed systems. ... |
[
"If you boil down peroxide enough will you eventually get pure H2O2?"
] | [
false
] | If no, then why not? | [
"The decomposition of hydrogen peroxide is accelerated by heat. There are no conditions where its decomposition ",
" thermodynamically favourable."
] | [
"You may have a hard time getting hydrogen peroxide to persist long through boiling, but it can be concentrated through other means.",
"It's an incredibly dangerous material to attempt to concentrate though, it is highly reactive and will give off explosive and corrosive vapors.",
"Many peroxides are exceedingl... | [
"Just in case you are considering trying to make or acquire high purity hydrogen peroxide, you should know that in high concentrations it can be extremely dangerous. Among other things it is a poison, will bleach skin, and if improperly handled or disposed of can easily mix with things that will form an explosive m... |
[
"On USGS DYFI maps, how plausible is it that people are feeling M4.3 earthquakes almost a thousand miles away?"
] | [
false
] | Often times I’ll be looking at an earthquake report and reading the Did You Feel It responses. For the , some people report feeling it in Santa Rosa, or even in Salt Lake City, which are all 400-600* miles away. Is this plausible scientifically? | [
"Relatively unlikely given the details, though we'll return to this below. Given that it's a public system, it's expected there will be both intentional and unintentional misreported data to the Did You Feel It (DYFI) system. In response, the USGS does a variety of filtering to try to remove outlier reports for dow... | [
"This is the kind of detail that will lead to some of the variance they observe in a given location, but the fundamental idea is that things like the DYFI maps are spatially aggregating responses so if the response rate is high enough, details like that will tend to average out. The questionnaire does ask whether y... | [
"What about being on the ground floor vs the top of a high rise?"
] |
[
"If water must be boiled to be sterilized, why do I only have to heat my chicken to 165 degrees F?"
] | [
false
] | null | [
"Boiling doesn't completely sterilize water. It is however convenient and easy to do, and drastically reduces the numbers of pathogens in contaminated water.",
"Likewise, you don't ever completely sterilize food by heating, you do however reduce bacterial numbers to an acceptable number. The reason that you can... | [
"Yeah, dealing with bacteria is a numbers game, you rarely ever kill all of the bacteria. You only have to heat chicken to 165F if you just got it from the store, and it doesn't have a funny smell. Then 165F is enough to kill most of the bacteria one expects to find in fresh chicken. If it's rancid, there could be ... | [
"I'm taking a foods 101 class in high school, and the answer I got was vague; The bacteria and pathogens normally found in chicken are different than the ones in water, so they require a higher temp to be killed. I believe it is the same for all types of meat meaning that they all have to be cooked at certain temps... |
[
"Does Guaifenesin affect all mucous secretion?"
] | [
false
] | Including secretions in the digestive tract? | [
"This is weird, because it runs completely counter to my own experience. I had asthma and quite a few bouts of bronchitis as a kid, and now whenever I get a cold I will get a cough that descends into my chest and requires me to cough very hard, very often, to keep my airways from building up firm mucus. Taking guai... | [
"Fun little tid bit is that guaifenesin really isn't that great for thinning airway mucous. There is a 2004 article in American Family Physician that said that the only difference was a reduction in coughing.",
"Truthfully the whole glass of water you're recommended to take with the drug works just as well if no... | [
"If you want cough suppressant, dextromethorphan is the only way to go. If you want to thin secretions, pseudoephedrine works for most people but you'll have to ask the pharmacy counter for it because you can only get a limited supply each month due to one of its ingredients being used to make meth."
] |
[
"What molecular signal initiates the physiological process of muscular hypertrophy?"
] | [
false
] | [deleted] | [
"Exercise induces",
" ",
"growth hormone",
" expression. Growth hormone ",
"acts in the liver to stimulate IGF-1 release",
". ",
"IGF-1 acts in the muscles",
" to stimulate ",
"calcineurin",
" and the ",
"AKT-mTOR pathway",
". Calcineurin stimulates the transcriptional (RNA) program to repa... | [
"No its pretty different. Smooth muscle cells are in the intestine, vasculature, and bronchioles. Smooth muscle is very different from skeletal muscle (though clearly they are both still muscle). ",
"A quick glance suggests a lot of different factors can cause smooth muscle hyperplasia but EGF and serotonin se... | [
"No its pretty different. Smooth muscle cells are in the intestine, vasculature, and bronchioles. Smooth muscle is very different from skeletal muscle (though clearly they are both still muscle). ",
"A quick glance suggests a lot of different factors can cause smooth muscle hyperplasia but EGF and serotonin se... |
[
"What are the raw ingredients of birth control pills?"
] | [
false
] | null | [
"Birth control pills are made with synthetic hormones, usually estrogen and progestin. ",
"The ",
"wikipedia article on Progestin",
" has a brief description of the synthesis.",
"For a much more detailed story, check out this article:",
"http://www.med.nyu.edu/content?ChunkIID=21816",
"Yams and soybean... | [
"The Active Pharmaceutical Ingridient in birth control pills is progesterone-like hormone. It can be synthesised from saponins from wild yam plants. Saponins contain the steroid structure which is needed for the synthesis of steroidal hormones. You can compare theese to molecular structures and see the similarities... | [
"I couldn't find anywhere the actual precursors they still use, but I suspect it's still very similar to in the 50s. Yams are a very economical precursor source for progesterone synthesis. You can make pounds of progesterone for a few dollars, which would be enough to dose thousands of patients."
] |
[
"Can a photon at λ=0 exist, despite the infinite energy required by E=hc/λ?"
] | [
false
] | null | [
"No. You can't have a wavelength of zero. If there's zero distance from one peak to the next, and half that distance from peak to valley, then the peak and valley are going to have to be in the same place, so it has to have both the maximum and minimum electromagnetic field. That makes no sense."
] | [
"Hey, this is a great answer. I do, however, wonder still about this, leading from your answer. What does this mean for a photon in superposition?"
] | [
"Superposition just means adding them together. If you superimpose a photon with a peak at one point with one with a valley at that point, you'll get a photon with a node at that point.",
"If you have a photon entangled with another particle you can have the photon be at a peak with the particle at one place and ... |
[
"Is the earth's atmosphere perfectly spherical?"
] | [
false
] | I know that it gradually fades away, but is it more dense/bumps over land and sort of drops over water? | [
"I'm going to go through with you on this in order of most significant to least significant",
"Firstly it's more or less oblong and is thicker at the equator due to earths rotation.",
"Secondly, the moon pulls on the atmosphere similar to ocean tides",
"Thirdly, convection would cause the atmosphere to be sha... | [
"The atmosphere also fluxes with temperature. There was even an idea to use the HAARP antenna in Alaska to heat and swell the ionosphere. This would increase the atmospheric drag on low-orbit space debris and help them re-enter sooner. "
] | [
"Gravity isn't uniform over the Earth's surface and I assume it affects atmospheric 'level' in a manner similar to how it affects sea level. If you haven't seen it, here's a great Minute Physics video that explains how the difference in gravity can cause changes in sea level of +/-70 meters:",
"https://www.youtub... |
[
"What, if any, advantages do beech and oak trees gain by holding on to their dead leaves months longer than other deciduous species?"
] | [
false
] | [deleted] | [
"My thought is that it relates to the location of the root system and the cost-benefit between hydration and damage. Most trees concentrate their roots around the ",
"drip line",
". \"A tree’s dripline is a ring around the tree canopy on the ground level that receives most of the\nrainwater shed from the tree... | [
"I was taught that the leaves remain in place to protect to buds that haven't developed yet"
] | [
"The retention of dead leaves that are normally dropped is called ",
"marcescence",
". That wiki link connects to some papers describing the potential benefits."
] |
[
"How do scientists capture the movement of subatomic particles as an image?"
] | [
false
] | When ever i see an article about neutrinos, quarks, or atomic physics in general i tend to see accompanying images of What's going on here? | [
"There are many different types of particle detectors, they can be split in to two generic types, tracking detectors and calorimeters.\nType 1) Tracking detectors:\nThese can only detect charged particles, as they traverse the detector.\nExamples of these are bubble chambers [1], cloud chambers [2] and more recentl... | [
"Great explanation! I loved that cms image link."
] | [
"I chose CMS as its what i work on ;)"
] |
[
"When cycling, how much drag can hair actually cause?"
] | [
false
] | I cycle to and from work, in my spare time, etc. I'm curious if there has ever been an in-depth look into how much drag your hair can actually cause. I've got fairly thick hair, I push it to the side and slightly up; the wind catches it. I see that professional cyclists have tight caps they wear. Have there been any controlled experiments on the matter? Does it make a night and day difference? Thanks. | [
"Specialized did some tests regarding this earlier this year: \n",
"http://www.stickybottle.com/coaching/are-you-more-aero-and-faster-with-shaved-legs-these-wind-tunnel-results-are-staggering/",
"These were of course wind tunnel tests but quite many seconds over a rather short distance. But for the average comm... | [
"Lemond also had aerobars/time-trial bars, which likely made a much larger difference than his helmet."
] | [
"I don't know how scientific you would consider it, but pro and semi-pro cyclists mostly agree that shaving your legs saves you several seconds over each hour of riding. ",
"Shaving arms and faces has a smaller effect, as the legs move faster with respect to the air (all that forward and backward motion)."
] |
[
"Why do our voices age and how? (Why do old people sound different than say a 40 year old, etc)"
] | [
false
] | null | [
"Speech/Lang student here! As you grow from a child to an adult, you vocal folds lengthen and strengthen (hence why your vocal range is larger and deeper than that of a child). But as you grow old, your vocal folds weaken. Vocal folds are like any other muscle in your body, they get stronger until a certain age and... | [
"will they start to weaken if you don't use them much?"
] | [
"To a lesser degree. Your vocal folds will still weaken with just age, but if you learn good vocal fold usage they won't be nearly as damaged / compromised when you're older. No smoking, very little throat clearing, soft onsets of sounds, speaking at a reasonable volume. All of these things not only help vocal heal... |
[
"How effective is washing your fruit and vegetables in removing pesticides?"
] | [
false
] | I always rinse fruit and veggies with water before cooking/eating them thinking that it removes most of the pesticides, but my roommate says this is pretty useless in terms of removing pesticides. | [
"A three-year study showed that rinsing under tap water significantly reduced residues of nine of the twelve pesticides examined across fourteen commodities. Four fruit and vegetable wash products were found to be no more effective at removing eight of nine pesticide residues from produce than either a 1% solution ... | [
"It depends.",
"What is the dose? What is the frequency of ingestion? What is the specific pesticide being used? All of these questions will drastically effect the answer. Also, some of our answers are still being researched and formed.",
"It's hard for me to answer because I do not know what are the most popul... | [
"Follow-up question: Is it necessary to wash fruit or veg before cooking? Would the heat and moisture remove the pesticides anyway? "
] |
[
"Are there waves of air on top of our atmosphere like waves of water on the surface of the ocean?"
] | [
false
] | null | [
"Well, sort of.",
"There's no real top to our atmosphere the way there is a surface of the ocean - it just sort of gradually thins out.",
"With that said, though, both experience the same kind of ",
"gravity waves",
". Note these are not at all the same as ",
" waves you'd see around a black hole - simila... | [
"Kelvin-Helmholtz wave clouds are formed when there are two parallel layers of air that are usually moving at different speeds and in opposite directions. The upper layer of air usually moves faster than the lower layer because there is less friction. In order for us to see this shear layer, there must be enough wa... | [
"There is a phenomenon known as stratospheric mountain waves which are loosely akin to this. Extremely powerful updrafts that reach into the stratosphere. Recent projects have sought to build sailplanes that could surf these mountain waves to get instrumentation to those high altitudes. ",
"https://en.wikipedia.o... |
[
"Could you actually fall into a black hole ?"
] | [
false
] | As I understand it, time goes faster and faster (in your reference frame) as you approach the speed of light (in the black hole's reference frame) when falling into a black hole, until it eventually gets infinitely fast. But thanks to Hawkins radiation black holes have finite lifespans, so woudn't the black hole die before you reach its event horizon ? | [
"If you jump into a black hole, you will pass the event horizon and reach the singularity within a finite amount of time. For most stellar sized black holes, this takes a small fraction of a second from your point of view though as you're shredded by tidal forces so you won't be alive for it. For super-massive blac... | [
"In General Relativity the concept of a gravitational force like F ~ r",
" is done away with all together. You’ll never actually calculate any forces in GR like you would do with classical physics. ",
"This might answer some of your questions "
] | [
"It appears you have the idea of the singularity and the event horizon slightly muddled. ",
"Time from your reference frame essentially always goes at the same speed. But in order for you to witness the universe ending etc., you would have to reach the singularity.",
"The singularity is far inside the event hor... |
[
"Why is the oxygen to hydrogen mass ratio on the shuttle's external tank 6:1 instead of 8:1?"
] | [
false
] | Wouldn't a mass ratio of 8:1 be optimal? | [
"An optimal reaction is indeed a 1:8 ratio, but having unburnt hydrogen in the exhaust produces a higher specific impulse.",
"That is to say the fuel is more efficient in producing thrust when in a 1:6 ratio, even though energetically it is more efficient at 1:8."
] | [
"Very interesting. Can you give us the very simple Newtonian mechanics explanation of why that is the case? Clearly it is due to the lighter hydrogen atoms/molecules. But in an ",
"ion thruster",
", in contrast, they use the heavy Xe atoms."
] | [
"This is exactly right. A rocket exhaust's efficiency is purely a function of the velocity of the exhaust gas. The Hydrogen will move at a much higher speed per given energy than the water, so it is more efficient.",
"As a side note, this is exactly how you'd create high efficiency propulsion with a thermo electr... |
[
"Where does the electron get its charge from?"
] | [
false
] | null | [
"It is a fundamental property of the electron. It is not believed to result from interactions with other particles the way mass is."
] | [
"There is no answer beyond the fact that electrons have charge."
] | [
"No, as they consist of quarks. This is true of the constituent quarks, however."
] |
[
"Can Anti-Matter Elements Exist?"
] | [
false
] | null | [
"Yes, and we've created some of them."
] | [
"Could you list the ones that have been created? I’m interested in this topic. Thank you!"
] | [
"Here",
" is some info about it, I don't know how up-to-date it is."
] |
[
"Does the tar from smoking really cause lungs to turn black?"
] | [
false
] | I have seen the pictures and know conventional wisdom states that the lungs of smokers turn black due to smoke, however I came across which refutes the claim. I know it's from a biased smoker blog, however the cited references seem reasonable. The basic idea is that it's emphysema which causes black lungs and not tar, and while emphysema incidence is higher among smokers that doesn't mean that all smoker's lungs turn black. is what an image search for emphysema turns up. One of the most striking claims I think is that smoker's lungs are routinely used for transplants. Would blackened lungs really be transplanted? About 13 percent of double-lung transplants in the U.S. came from donors with a heavy smoking history, according to Taghavi’s new study, presented Tuesday at the annual meeting of the Society of Thoracic Surgeons In the end, after all other variables were accounted for, people who got lungs from heavy smokers lived as long and as well as those who got lungs from the tobacco-free, Taghavi found. There was no significant difference in cancers, though the study didn’t specifically look at lung cancer. | [
"Emphysema is a disease that causes damage to the lung tissue so that the tiny air spaces grow into relatively huge air spaces. You need a high surface area to transfer oxygen from the air into the blood, so when the tissue separating the tiny air spaces is destroyed to make bigger ones, you lose surface area and c... | [
"The problem is that it's virtually impossible to know if you're susceptible to lung disease from smoking unless - yanno - you smoke for 50 years. The damage builds up so slowly. ",
"I've had patients come in and say they've smoked 60 a day for 60 years, and their lung function is perfectly normal. I've had patie... | [
"For the kids and partners of smokers, the effects can be similar to if they'd smoked themselves. Again, returning to \"in genetically predisposed people\", so it'll vary VASTLY from person to person. ",
"But like I said: they won't know if being around smoke is gonna make them sick until YEARS after they were ar... |
[
"Why is it that strong negative emotion can give someone a sick feeling in their gut?"
] | [
false
] | It's a weird sensation, just wondering why it happens and how it works... | [
"In fact, about 95% of the body's serotonin is found in the gut, not in the brain! ",
"http://www.scientificamerican.com/article.cfm?id=gut-second-brain"
] | [
"I have generalized anxiety disorder so I know this feeling well. I have read before that it's due to serotonin receptors in your stomach, and also that it's due to the release of epinephrine, as your body is priming it's fight-or-flight reaction."
] | [
"That's crazy when you think about people trusting their gut, or 'gut feeling'... go figure, maybe it's not such a bad idea sometimes"
] |
[
"Biology question: Will 192 degree water kill bacteria in one cup coffee maker?"
] | [
false
] | [deleted] | [
"Your temperature is fine, but you seem to have seven times as much DNA as a normal person."
] | [
"Laboratory-grade sterilization requires 15 minutes at 121 degrees celsius, however for your purposes you should be fine. I know from experience that at 95 C that 5 minutes is enough to reduce bacteria to less than 1 part in 10",
" and your machine is at 88 C, so you will probably kill most bacteria."
] | [
"This comment was hilarious."
] |
[
"Does our brain process the image our eyes see all at once, or does it start at one point and move from there (like starting in the centre and moving outwards, or from one side to the other)?"
] | [
false
] | Idk if this is something that we have the technology to test, but I just wonder if this is a known thing or are there some working theories or something? Also, knowing this could be used for things like marketing and creating illusions, right? | [
"Primary processing of different areas of a visual field will happen simultaneously, as the cells doing the processing are actually topographically organized. However, because there is greater detail in the fovea (dead center) of your visual field, there's simply going to be more raw information to speed up downstr... | [
"Depends on what you mean by “process”. All the light from a scene in our field of view hits our retinas near-simultaneously, and so we form a visual representation of it all at once. After that, certain things are attached saliency by the associated brain networks, but it’s not always location dependent."
] | [
"However, because there is greater detail in the fovea (dead center) of your visual field,",
"And to be clear, it is ",
" greater detail. The fovea is essentially the only place we have clear vision. We don't notice this because we can move our eyes very quickly to focus on different areas, and our brains are v... |
[
"Is it true that 40% of all domestic violence victims are men?"
] | [
false
] | Is it true that an astounding 40% of domestic violence is against men? I knew that domestic violence VS men was under reported, but this seems unreal. | [
"Counting victims who have experienced domestic violence at least once in the previous year, that is correct (recent British Crime Survey result). Counting incidents, 90% are committed against women.",
"Data on perpetrators are not routinely collected. DV is defined as violence against any family member over the ... | [
"That is either journalistic rephrasing, or the study failed to describe the data accurately. The definition of domestic violence, as used by the BCS, is given on page 4 here: ",
"http://collection.europarchive.org/tna/20090120202659/homeoffice.gov.uk/rds/pdfs04/rdsolr1804.pdf"
] | [
"I'm confused, how can 40% of the victims be men if 90% of incidents are committed against women?"
] |
[
"Is the periodic table of elements valid in everywhere in this universe?"
] | [
false
] | null | [
"Yes, as the laws of physics are the same everywhere - at least within the (very small) current measurement uncertainties and within the observable universe."
] | [
"Yes*, the periodic table is valid everywhere.",
"*The atomic weights listed on the table are not. The atomic weights are an average of all the different isotopes that are commonly found on Earth. How much of each isotope there is depends very much on where you are in the universe. The relative abundance of diffe... | [
"It's a natural assumption that the laws with its constants are the same everywhere but we check, of course. If the fine-structure constant would be significantly different elsewhere then many heavier elements would behave differently. People checked: It is not. Similarly, a different proton to electron ratio would... |
[
"How is Zero Gravity simulated?"
] | [
false
] | I'm trying to figure out how the "Vomit Comets" produce microgravity/zero gravity as well as a . I "Vomit Comets" produce microgravity as a result of angling the plane downwards to minimize drag as they free fall? Would you experience microgravity in a plane if you simply stalled it and fell tail first or belly first rather than nose down? I know that NASA utilizes "drop tubes" where they surround a payload with a drag shield, in a Vomit Comet, is the plane acting as the drag shield for the "human payload"? And can anyone explain how the rollercoaster produces zero go effects? There is no drag shield, so riders are experience friction with the air and they experience zero g while going UP as well as down? Thanks in advance, I'm quite tired so these questions are likely a large mess of words, my apologies. | [
"It has little to do with drag or other aerodynamic factors. ",
"Imagine throwing a ball into the air. It will travel in a parabolic arc.",
"Now imagine that ball is surrounded by an airplane, travelling in the same path, at the same velocity. To those in the airplane, the ball will appear float in the air fo... | [
"If you have no net force exerted on you, other than gravity, you experience \"zero gravity\"."
] | [
"The parabolic flights are necessary because they track the path that an object in a vacuum would fall.",
"When people talk about experiencing weightlessness on a roller coaster they are only talking about the main downhill drop segment. And I don't think anyone is claiming that it's true zero-G, just a similar ... |
[
"If we covered half the sun in a reflective mirror, how much thrust would all the reflected light and heat create?"
] | [
false
] | If a solar sail generates thrust, how much thrust would our sun make if we covered one hemisphere in a reflective mirror to direct everything backwards? | [
"So, given the mass of the sun is about 2 * 10",
" kg, that would mean you get about 3 * 10",
" m/s",
" acceleration. After about a million years the sun would get up to a velocity of 10 meters per second."
] | [
"You have that the momentum associated with light is the energy over c. Therefore the force on a mirror is:",
"F = 2 L / c",
"where L is the power and the 2 is because the photon bounces.",
"The total power emitted by the sun is the solar luminosity L = 3.846×10",
" W.",
"Now, if we take the power emitted... | [
"What if we included the solar wind in this calculation? If we're somehow building megastructures with the intent of moving the sun, it seems we need to account for everything the sun puts out. ",
"Of course, this raises the question of why someone would want to move a star. If you have the magical-level of techn... |
[
"Why does it seem that there’s more and more people allergic to more things?"
] | [
false
] | [deleted] | [
"Just to expand on this a bit more, most human parasites are known to produce molecules that inhibit our immune system. Many of them specifically inhibit our ability to mount allergy/anti-parasite responses. One theory then is that our immune system has evolved to react too strongly to parasites so as to overcome t... | [
"Just to expand on this a bit more, most human parasites are known to produce molecules that inhibit our immune system. Many of them specifically inhibit our ability to mount allergy/anti-parasite responses. One theory then is that our immune system has evolved to react too strongly to parasites so as to overcome t... | [
"Having difficulty agreeing with your argument. There seems to be more support for the hygiene hypothesis in the scientific community to explain the rise of allergies in developed countries, rather than them being undiagnosed.",
"An allergy and an intolerance are not the same. An allergy is driven by an immune re... |
[
"Does the energy of an alpha particle affect it's chance of capture?"
] | [
false
] | Hey . I've been learning about some nuclear physics/engineering lately, and recently learned about the (alpha, n) capture reaction with aluminum 27. With interest in spectroscopy, I ask: does the energy (MeV) of an alpha particle affect the chance that a light metal, in this case aluminum, will capture the alpha particle? (which happens normally when aluminum is bombared with alpha particles). I think I know the answer, but I just wanted to check here first. Thanks! | [
"So, would a difference of something like 300 KeV be a noticeable difference in capture chance, or is that an insignificant energy difference?"
] | [
"So, would a difference of something like 300 KeV be a noticeable difference in capture chance, or is that an insignificant energy difference?"
] | [
"Yes, especially near resonances. "
] |
[
"Which country has been most successful at combating pollution, and what did they do to be so successful?"
] | [
false
] | There are obviously a lot of outliers here with some countries being so abysmal initially almost anything they did would have a large impact. Looking to see which method(s) would be most successful in a country that doesn't have an abundance of low hanging fruit. | [
"I would say Bhutan. They restored large area of forests and even pledged to keep a percentage of area in the country reserved as forests.",
"They use hydroelectricity and their population is barely a million. So I assume they got all the power they need and more.",
"The forests are so connected and large that ... | [
"For anyone who have lived on both sides of the Atlantic, there are a number of contrasting things that highlight the disparity between US and Europe. It isn't necessarily any one single nations, but in many places in Europe, the sorting and separation of garbage is taken a lot more seriously than the states. Spa... | [
"What a great story. Thanks for sharing."
] |
[
"Was there any species that lived both in the Old and in the New world?"
] | [
false
] | Apart form humans, was here any species whose area covered both the New world and the Old world before the discoveries? | [
"Brown and polar bears."
] | [
"I'll add ",
"tapirs",
" to the list... technically they are separate species, however they are so unique in form and function that it is interesting that they are only found both in central and south america as well as the south pacific. And ",
"ospreys",
" although they are found globally (except Australi... | [
"Species which live near the Arctic and Antarctic circles are more commonly spread out, since they have less distance to travel and are better adapted to travelling over the cold areas needed to take these shortcuts(as is the case with polar bears.) Aquatic species likewise are able to have a wide range because th... |
[
"An impact crater has been recently discovered in Greenland that may have been caused by a 1-mile-wide asteroid. If an analogous asteroid were discovered heading towards Earth, would we be able to pinpoint in advance an exact impact location? How much time in advance?"
] | [
false
] | null | [
"We have several projects underway to use automated telescopes to find these objects, including the ",
"Catalina Sky Survey",
" and the ",
"Pan-STARRS",
" project. One of their biggest achievements is that they have probably found and tracked every asteroid that could impact the Earth that is 1 km across (... | [
"\"probably found and tracked every asteroid that could impact the Earth that is 1 km across (0.6 miles) or larger\" does not mean \"They found them all\" ",
"They PROBABLY found the asteroids that are over 1km across. Smaller objects, non-asteroid objects and maybe some object we've missed (because it doesn't re... | [
"It is a pretty bold claim: it sure shocked me when I heard an asteroid expert make it! You're right to be skeptical, and nobody's suggesting we should stop looking. ",
"As we keep looking, we keep finding more and more small asteroids, but we've stopped finding more big ones. In 2000, early in the automated s... |
[
"Is it possible to simulate evolution of a computer out of logic gates?"
] | [
false
] | Given modern computers in a simulation of NAND (or other ) logic gates and how they may be connected, is it possible to evolve a computer out of these primitives? I ask this because I have seen a clock evolving out of clock parts as per As I think more about this it seems to me that if it were true, the basic stages would be formation of half adders, adders, multiplexers and things like that and eventually a real computer that can do fetch-decode-execute cycle. Also, is it possible to evolve something more advanced than a computer? If we can simulate, how would one carry out constructing such a simulation? How could we select a fitness function for it? | [
"This sounds like it would be theoretically possible to do, if we had enough time.\nIn the clock video and in nature, evolution needs some form of determining what entity is most fit. In the clock video, a computer selected clocks based on their ability to tell time. In nature, a species ability to survive and proc... | [
"No, the speed of light in Life is 1 block per frame. That's the information propagation limit, and it's fairly trivial to construct a chain of some sort that disintegrates at light speed. You're getting it a bit confused with the fact that no known spaceships — cohesive independent self-translating figures — trave... | [
"It is not true that \"any Turing machine can emulate any other Turing machine.\" It is true that there exists such Turing machines; such a Turing machine is called a Universal Turing machine."
] |
[
"Is there any evolutionary benefits other than sexual selection in having blue or green eyes instead of brown?"
] | [
false
] | And other than Caucasian is there any examples known other than those of mixed race with Caucasian that have had the mutation that causes blue or green eyes? | [
"Like skin tone, lighter eye color is simply a reflection of lower pigmentation (less melanin). As with many genes, if those genes that influence eye color can mutate to less active forms without dicouraging the survival of a given organism, they may continue to mutate to less and less active forms. This means that... | [
"Thus far no proven advantage but it is possible that the genes that contribute to blue & green eye color could be associated with other traits that confer advantage (such as lighter skin tones in northern latitudes).",
"Blue eyes in humans results from a single genetic mutation which probably spread through foun... | [
"Since we know that skin and eye color segregate independently, it's doubtful that lighter eye color has anything to do with vitamin D production.",
"Not really true; the ",
" locus is associated with nearly all eye-color variation but also with some skin-color variation, and may be involved in melanin precurso... |
[
"Is there evidence to suggest prehensile appendages on any dinosaurs?"
] | [
false
] | Are there any characteristics of bones in modern animals (elephant, rhinos monkey, etc) that suggest they have an ability to grasp with(monkey) or without(elephant) the bones themselves? If so, has paleontology found anything that would suggest so in dinosaurs? | [
"The only thing I am aware of is the relative sizes/amount of foramen in the skull for the additional/enlarged nerves needed to control prehensile lips/trunks etc. I remember reading that analysis of some dinosaur skulls had indicated that some species had prehensile lips like a modern rhinoceros."
] | [
"Etymologically, prehensile means ",
" or ",
". With such a loose connotation, it's easy to suggest that many parts of the body could be considered prehensile. However, although definitions vary for different body parts (tails, tongues, feet, etc.), definitions almost all imply the ability to not just ",
" an... | [
"Do humans not have prehensile lips?"
] |
[
"Can bacteria die of old age?"
] | [
false
] | null | [
"Yes, over time bacteria accumulate damaged DNA, misfolded proteins, and old membrane/cell wall material. If it accumulates enough of these it will die.",
"When bacteria divide it groups all of these things into one side (called the old pole) before splitting in half. The daughter cell inheriting this old pole te... | [
"That's actually a great question, I think it would be very tough to test in practice though. There are 'stem cells' that constantly replenish other cells that die off (like your skin and hair), and it would be interesting to know if protein aggregates and whatnot are concentrated in the differentiated cells more ... | [
"Do multicellular organisms also push all the defects onto one of the daughter cells? At least to a small extent?"
] |
[
"If I had a 0.999... cm width chocolate cake, I can add some more chocolate and reach 1 cm. However, if I had the dimensionless/unitless number 0.999..., then it's equal to one. How?/why?"
] | [
false
] | null | [
"Well, if we're working with atoms, then 0.9999999cm and 1cm would have the same number of atoms, because atoms are only so big. The physical world is a ",
" bad place to try and understand the real line. But, for argument sake, if wood is continuous and you're cutting up wood to get 0.9cm, 0.99cm, 0.999cm, lengt... | [
"If you had 0.999...cm width of chocolate cake, then you would have 1 cm width of chocolate cake. 0.999... and 1 represent the exact same number, there's no difference. 0.999...cm = 1cm."
] | [
"If you had 0.999...cm width of chocolate cake, then you would have 1 cm width of chocolate cake",
"Physically speaking, would 0.999...cm of, say, some wood, be different from 1cm of wood?",
"As in, would both be composed of the same number of atoms?",
"For example, ",
", ",
", and so on.",
"Now, given ... |
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