title list | over_18 list | post_content stringlengths 0 9.37k ⌀ | C1 list | C2 list | C3 list |
|---|---|---|---|---|---|
[
"How does putting whisky on a mouth ulcer heal it?"
] | [
false
] | [deleted] | [
"Alcohol is a good disinfectant. It kills a wide range of micro-organisms and is mostly benign to healthy tissue. Whisky is about 40% ethanol, a good concentration for this purpose, although 60% would probably be better.",
"The ethanol kills off the surface micro-organisms that are hindering healing thus allowi... | [
"Both alcohol and salt are excellent disinfectants, they dry out cells, which is a major problem for single celled organisms (while us multicellular organisms can easily recover from a few dehydrated cells!). Viruses are also susceptible to drying out from these processes. I can't speak for TCP but it may have a si... | [
"100-120 proof Whiskey are fairly common, although dwarfed by the number of 80 proof varieties out there. So it is pretty easy to the better concentration of alcohol. "
] |
[
"Is there an evolutionary reason that aquatic reptiles (such as ichtyosaurs) moved their tails horizontally, while aquatic mammals move their tails vertically?"
] | [
false
] | null | [
"Marine mammals and reptiles do not only use their tails for swimming, they use their whole body. The direction of undulation (lateral in reptiles and dorso-ventral in mammals) came from their respective terrestrial ancestors. Reptilian locomotion on land retained the ancestral state of the early tetrapods and is, ... | [
"No. It's totally wrong. Look at a skeleton: whale tails look like vertebrae because they are an extension of their spine, just like reptile tails. They even have vestigial legs remaining about 2/3 of the way along their bodies, with leg bones and foot bones and everything (but the structure is inside their bodies,... | [
"No. It's totally wrong. Look at a skeleton: whale tails look like vertebrae because they are an extension of their spine, just like reptile tails. They even have vestigial legs remaining about 2/3 of the way along their bodies, with leg bones and foot bones and everything (but the structure is inside their bodies,... |
[
"If temperature is merely a measure of kinetic energy, what exactly is the colour temperature of blackbody radiation?"
] | [
false
] | I'm a little confused by the concept of temperature, so perhaps someone could clear this up for me. On one hand, temperature is merely a measure of molecular vibrations. Our brains interpret these vibrations as temperature, and when the kinetic energy in two substances is different, placing these substances together causes the kinetic energy between them to average out, which is the basis for the concept of heat transfer. Is that all correct? (Also, if all of that's the case, does that mean that there's a simple conversion factor between joules and Kelvin?) But then on the other hand, temperature is also this more abstract concept related to blackbody radiation and Wien's law, where every colour has an associated temperature and these colours are the wavelengths whose energy is equal to the energy released in an atomic deexcitation. Is that also correct? I'm having trouble unifying these two concepts of temperature in mind. In one case, we're talking about kinetic energy in classical physics and in the other case, we're dealing with quantum mechanical principles. On top of that, I'm guessing that true blackbody radiation doesn't actually exist, as light can never be perfectly thermalized, so where does EM radiation that is true blackbody radiation fit into the whole colour/temperature discussion? Perhaps someone can help make sense of these seemingly disparate ideas and help me understand the concept of temperature. Thanks. | [
"The temperature as molecular kinetic energy explanation is ok but not the best. The actual definition of temperature has to do with the relationship between energy and entropy.",
"To relate the molecular motion picture to blackbody radiation, consider an atom with an electron that jumps between energy levels, em... | [
"The example I gave is basically to demonstrate that a continuous spectrum can arise from thermalization of discrete spectra. It's not a derivation of Planck's law."
] | [
"If this really is accurate, then I'm confused.",
"From this subreddit and other resources I have gathered that blackbody radiation is generated by the rapid oscillation of charges in the hot matter. Thus, the spectrum is continuous because the particles' energies are distributed that way. The Doppler effect, in ... |
[
"When a wound heals, does it grow just as fast as your other skin?"
] | [
false
] | null | [
"I got a small, but deep wound last Sunday, when a piece of burning wood got stuck on my finger. It was maybe 7-8 mm wide and 2-3 mm deep. Five days later, it is almost healed. This got me thinking:",
"Does skin grow this fast everywhere else? ",
"If not, how does the cells \"know\" that they have to grow back?... | [
"Skin usually grows at a common rate, depending on location. They just grow until they die, forming your epidermis.",
"So it's an ever-growing layer of skin, up to your outermost layer where they flake off into dust, making it pretty constant."
] | [
"No, the growth depends on several factors.",
"From ",
"The Pathogenesis of Burn Wound Conservation-",
"\"The ability of the skin to heal largely depends on the dermis. The contained macrophages produce growth factors, fibroblasts, and extracellular matrix, which control epidermal regeneration. Since the hi... |
[
"Why are LEDs (Light Emitting Diodes) only capable of producing a few colors?"
] | [
false
] | I asked this question in AskReddit without knowing about AskScience. (See: ) There were some replies, but not the clarification and simplification of answers that I'd hoped for. The best answer there indicated that the "band gap" of the material used determined the color of the LED. I thought maybe AskScience would be the place to go. So, here goes: Why isn't there an infinite number of colors of LEDs? Why are there only a few colors that are commonly produced? For example, Wikipedia lists ten colors of LEDs: What's the long and short of it? What's the scientific explanation for this? -- Please explain your reasoning in detail and then again like you were speaking to a 5-year old. Thank you! I understand that you can take the commonly offered LEDs and combine them to produce a rainbow effect and possibly the entire spectrum of colors, but the question still remains: Why aren't LEDs offered in more colors? Is it just cost prohibitive to research the science behind creating less common colors? LEDs are very cheap, so the cost prohibitive argument for only a few colors seems flawed. Unless it's just the original research that is so expensive, because manufacturing obviously isn't. Is it an issue of what material is used, and the "band gap"? (As mentioned above) EDIT: Thank you for the awesome answers and discussion! Very informative and thorough. | [
"The band gap first:",
"Electrons exist in atoms in very specific, discrete energy levels. Electrons cannot - absolutely cannot - have energies in between these 'allowed' energy levels. They can move up energy levels if you give them a bit of energy that exactly equals the difference in energy between those two... | [
"Wow. Thanks for your thorough explanation. This seems to make a good deal of sense.",
"So, from your explanation, it is an issue of materials and their physical properties, rather than research costs, etc. ",
"It seems interesting that the discrete colors produced are almost those of the standard rainbow. ... | [
"The problem with InGaN is that mixtures near 50% each have very poor quality crystalline. It becomes hard to tune near the center of the range."
] |
[
"At what size does quantum mechanics replace general relativity as the governing set of rules?"
] | [
false
] | So I know quantum mechanics are the laws that describe the interactions between subatomic particles and general relativity describes the interactions between macroscopic things. What I wanted to know is at what size does the switch between these two theories occur? And possibly why? | [
"They don't ",
" each other, strictly speaking. GR is a theory of gravity and QM (or, more accurately, quantum field theory) is a theory of electromagnetism, strong, and weak nuclear forces. This means that one theory doesn't turn into the other as you cross some size threshold - rather, they are two compliment... | [
"It's not that it's wrong, exactly, but rather that it's not the whole story. QFT is the best-tested physical theory in human history, and it works ",
". However, it's probably a limiting theory - there exists a more complete theory (i.e. one that incorporates gravity) that looks a lot like QFT on scales where g... | [
"Good answer, but I think you're describing the problem of quantum gravity a bit wrong. We can put a renormalizable QFT on a curved background and still compute things (which is how one finds the Hawking radiation, for example). The problem of quantum gravity is rather when you quantize gravity itself. Which might ... |
[
"What do we know about the supernova that created all the metals in the solar system?"
] | [
false
] | Is anything known about the supernova remnant that ended up being the solar system? I've tried looking around for some info, and if there are any papers that people know about, please pass them along. EDIT: Thanks for all the responses. | [
"It's not just one, atoms come from all over."
] | [
"I've wondered about this too. But when you consider that it takes ~1/4 billion years to rotate around the galactic center, and the sun is about 5 billion years old, we've gone around the galaxy about 20 times. That system may just be too chaotic over that long of a time scale to accurately plot back in time to whi... | [
"That's a good point, but I guess my question is might then be does anybody know how many supernovas contributed to the solar system?"
] |
[
"Is it possible to make a magnetic alloy from nonferrous metals or semiconductors?"
] | [
false
] | My (vague) understanding is that what makes a material magnetic has something to do with how stable electrons are in their orbits and how resistant those orbits are to change. I know that magnetic disk drives read using semiconductor chips that change their electrical resistance in the presence of a magnetic field. Is a non-ferrous, non-electrical magnet plausible? | [
"Of the pure elements, ",
" (ferrum) is the best-known magnetic metal, of course. It's so prototypical that 'ferromagnetism', the best-known kind of magnetism, is named after it",
" also are sometimes considered to include ",
" and ",
" in addition to iron. All of them are highly ferromagnetic and also have... | [
"Doping some semiconductors with impurities has been shown in recent years to sometimes create ferromagnetic effects. I know you said no semiconductors, but this doesn't depend on an electromagnetic effect to work, so I think this might be what you had in mind.",
"Here's ",
"one example",
" that I found quick... | [
"How are you defining nonferrous here? Not iron? Then yes, definitely. Hard disk drives use a cobalt chromium alloy. Both cobalt and nickel are frequently used to make ferromagnets."
] |
[
"Do cars with smaller tires use more gas than cars or trucks with larger tires?"
] | [
false
] | I hope I put this in the right category with the right flair. I apologize if not. My thinking on this was that cars with small tires need more revolutions per mile than cars or trucks with larger wheels, and therefore, smaller revolutions would utilize more gas to maintain the speed to go the distance needed. Am I thinking this correctly? | [
"No. Though certain factors like friction increase at higher engine speeds, engines are not always more inefficient at higher speeds. Ultimately, a truck requires more power and thus, more fuel to drive at a given speed than a car.",
"There are two factors in engine power, speed and torque. Speed is the speed of ... | [
"Thank you! I am not well versed in this, but I actually understood most of what you are saying. So, then, what you are saying, is a lighter car would actually use less gas because it would have less engine load or torque. I have a Toyota Celica and my gf has a Subaru Forrester, and her car eats up gas, where my ca... | [
"The kind of driving you do will have a large effect as well. The two main things that limits the motion of a vehicle are it's mass and drag. Mass will effect how much energy it takes to accelerate the vehicle, thus her smaller, lighter car will take less gas to get up to speed. Drag is proportional to velocity ... |
[
"Are there any animals that naturally have three ears? Or any with three eyes?"
] | [
false
] | I'm curious about the seeming (to me) lack of threes - is there a reason why aren't there more animals with three limbs, organs, etc? | [
"Many squamates (lizards) have a photosensitive third eye at the top of their head. it's not a fully evolved eye, but a cluster of light-sensitive cells.",
"http://www.amnh.org/exhibitions/past-exhibitions/lizards-and-snakes-alive/squamate-fun-facts"
] | [
"Many fish, amphibians, and reptiles have a parietal eye, though it rarely functional. The tuatara's is particularly well developed, retaining its lens, but is only visible in hatchlings, and is quickly overgrown. The primitive lamprey also has a developed third eye (two different ones, actually), and fossil evid... | [
"Symmetry is important because it allows you to do more with less genetic code.",
"Bilateral symmetry is so prevalent because while up and down, and front and back are different enough to warrant different adaptations, left vs. right is not. "
] |
[
"Has the discovery of martensite principles been at all important? Is this useful in any way, has it led to anything?"
] | [
false
] | null | [
"(Also, is this 'physics' or 'chemistry'?)"
] | [
"Since Martensite appears to be ",
"some sort of crystal structure",
", I'd say chemistry."
] | [
"Changed flair. Thank you."
] |
[
"Is time smooth? Or are there \"gaps\" in it? What is in those \"gaps\"?"
] | [
false
] | [deleted] | [
"You're referring to the quantisation of time. The general consensus is that time is continuous, although there is a fairly significant group that thinks it's quantised. As of now, there are no observations that suggest that time is quantised. "
] | [
"What implications could come out of time being quantized?"
] | [
"Quantized time would most likely be naturally coupled with quantized space as well. Also, there's some very interesting implications for the big bang and the concept of ",
"action",
" in physics."
] |
[
"Why can we drown after only a minute or two, but then get resuscitated a while later and still live? Why can't we just survive a few more minutes without breathing?"
] | [
false
] | Probably a stupid question, but I'm curious | [
"Here's a very simplified explanation. When you drown:",
"You're unable to get enough air into your lungs, because of the water.",
"You aren't able to get oxygen into your body. Your body continues to consume oxygen, and so the level of oxygen in your body decreases.",
"At some point, you stop breathing and y... | [
"Just certified in Washington state last Saturday. 30 seconds of chest compressions, 2 rescue breaths is what we were taught."
] | [
"Really? I am CPR certified and we used rescue breaths."
] |
[
"Why do physicists say that a photon has zero rest mass instead of saying that a photon doesn't exist at rest?"
] | [
false
] | At rest, a photon wouldn't actually represent any sort of force or material, so why talk about it in this way? Is it a form of potential energy and so considered something? | [
"A better term than \"rest mass\" is \"invariant mass\", or just \"mass\" (since \"relativistic mass\" is an outdated concept). You may have seen the equation for the relativistic energy of a particle, E",
"=m",
"c",
"+p",
"c",
". If we re-express this equation as E",
"-p",
"c",
"=m",
"c",
", we... | [
"Photons (or light) were not considered to be particles at all for a long time, so the concepts of momentum and energy were developed for \"traditional\" particles with rest mass, and only later were the equations rewritten to include photons. By that time it was necessary to describe the rest mass term as 0 to fi... | [
"I was speaking more at a historical level about why we can't write .5*mv",
" as the kinetic energy, etc., so the term \"rest mass\" doesn't apply. ",
"Maybe it's just the order I learned things, but it's my impression that the term reflects a transition from classical massed particles to the modern approach. ... |
[
"How does Paracetamol toxicity work?"
] | [
false
] | Okay, this is a bit of a strange one I know. There is a lot of rubbish regarding paracetamol out there. Many believe that using it long term can be bad for your liver for example. However the truth is that you're fine as long as you stay within the 'therapeutic' range. I was at work today (Admin at a GP surgery) and I scanned a letter regarding a patient that attempted suicide by consuming 30 paracetamol tablets and went to sleep. Apparently she was annoyed to have woken up seemingly fine. So what happened to this patient? Did she get lucky? Also, if it's safe to have up to 8 in a day does it matter how you divide the dosage throughout the day? For example could one take 3 two times a day instead? Why is the suggested dosage 2 four times a day? What if an individual took 4 twice a day? Would this be dangerous? It seems to me that paracetamol toxicity works quite differently to a lot of other drug overdoses? But that is basically my main question. If it's okay to have 4000 mg of paracetamol a day, does it matter how that is divided throughout the day? What may be the long term effects of taking more than 1000 mg every 4 hours? | [
"This is one of my favourite toxicity questions!",
"The reason it seems different to 'other' cases is because of how easy it is to do despite the fact it's a commonly used, easy to obtain drug.",
"Paracetamol is taken up by the body and relieves pain, high temperature, etc. 'After' that, like many drugs, it's m... | [
"I claim no special expertise on the matter, which is why I defer the case to my wife, a certified poison information specialist which has worked the emergency phone lines at a poison information hotline for 15 years.",
"While it is true that at therapeutic doses, acetaminophen is safe, beyond the threshold of ab... | [
"BTW, Tylenol is not a salicylate. "
] |
[
"If you recycle an envelope with a clear plastic \"window\" on it, does the plastic part interfere with the paper recycling process?"
] | [
false
] | Basically I'm wondering if it's worth the effort to manually remove the plastic window before recycling a windowed envelope. | [
"I work in a single stream recycling plant, it will most likely get rejected by the machines. "
] | [
"The entire envelope will be rejected and added to a waste or a low quality% fiber mix. ",
"The only thing that can have 2 materials are metals, such a concentrated frozen juice as the paper/cardboard burns off in the incinerators and the metal ends will remain. You should also separate plastic lids from bottles ... | [
"I am a plastic recycler and this is completely wrong. Everything is chopped up then put in a wash tank. The bottle tops are HDPE/PP and float while the bottle is PET and sinks. No need to separate beforehand. "
] |
[
"How does a Pulsar star let us determine distance to it accurately?"
] | [
false
] | I remember hearing this somewhere, but I forgot, and couldn't find it by googling. What is the calculation to determine distance to a pulsar star? How does its fixed period help us determine that? | [
"I think you might mean estimating distance to the pulsar using the pulsar dispersion measure. To put it simply:",
"The Pulsar emits light over a certain range of [radio] frequencies. As the photons travel towards us they interact with [mainly] free electrons in interstellar space. This interaction slightly prolo... | [
"Thank you, this is what I was looking for."
] | [
"I think you're half remember som facts about the plaque on the Voyager space probes. This map was designed by Frank Drake to shown the location of the Earth relative to 14 pulsars. Pulsars are rapidly rotating neutron stars which emit beacons of radio waves. The precise timing of the resultant radio pulses provide... |
[
"Why did every single species in the Homo genus except for Homo sapiens sapiens go extinct?"
] | [
false
] | From what I can gather Homo neanderthalensis for were intelligent enough to make tools out of bone and rock for example, so why couldn't they evolve alongside what would eventually become modern humans? Did our species' "merge"? | [
"To a first approximation, every species that has ever lived is now extinct, so the unusual thing is that H. sapiens is still around. ",
"Species don't last all that long, geologically. The average is a couple of million years, but much shorter periods are not unusual. Most of human ancestors and cousins probab... | [
"It's hypersimplistic to just say we outcompeted them. For fifty thousand years, sapiens and neandertalis took turns with Europe. When it was cold, the Neandertals dominated; as it warmed up, Neandertals moved North and sapiens moved up; then it cooled down again, and sapiens retreated to the sun and Neandertals m... | [
"Sure it's simplistic to just say Homo sapiens sapiens outcompeted other humans, but that doesn't make it inaccurate. My issue is that when people discuss humans they try to personalize things, overcomplicate arguments, and/or ignore biology. My argument is that biology and the inherent competitive nature of biol... |
[
"How can Antiprotons annihilate with Neutrons?"
] | [
false
] | I thought annihilation requires a particle and its specific anti-particle but I read in a book about antimatter that antiprotons annihilate with neutrons. How so? | [
"Hadrons are made of quarks. A neutron has valence quark content of udd and a proton has valence quark content of uud. So an antiproton has antiup and antidown quarks which can annihilate with up and down quarks in a neutron. They can’t fully annihilate each other; there will still be some quarks in the final state... | [
"Its possible! Pions are a combinations of quarks and antiquarks. ",
"",
"https://en.wikipedia.org/wiki/Pion",
"",
"There are three types and have been widely studied."
] | [
"So it would be possible to keep matter and antimatter closely together with no annihilation happening if you make sure that they have no quark type in common?",
"Not sure if any kind of matter/antimatter combination exists which satisfies that condition."
] |
[
"Does light always move?"
] | [
false
] | Are there any conditions where light can become stationary? I'm thinking maybe at the event horizon of a black hole? Would there be any way to detect that this was occurring? | [
" Yes.",
" It's a neat consequence of special relativity that light ",
" move at the speed of light. ",
"Einstein's two postulates that form the basis of special relativity say that (1) the laws of physics are the same in all inertial frames, and (2) the speed of light is the same in all inertial frames. One ... | [
"Light always moves at the speed of light ",
".",
"Light in a medium can be much slower. One way to look at it is that the photons are constantly hitting atoms of the medium, being absorbed, and then being re-emitted later, which takes time."
] | [
"Is it correct to say that the individual photons are moving at light speed within the medium, but the average velocity (group velocity?) is very low or zero? "
] |
[
"What do non-human primates do with their dead? How do they mourn them? What do they do with their bodies?"
] | [
false
] | null | [
"Chimpanzees mourn their dead and even have what could be described as rituals. Other primates seem to experience grief as well. This article describes ",
"death rituals in the animal kingdom",
". Warning: it's very sad. I still don't know what they do with the bodies. Apparently, it's pretty rare for humans to... | [
"Hello,",
"Turkish guy here. Magpie's are very common here and i really love them. i know they are not primates but i have a cool fact about them that seems relevant. ",
"https://www.eiu.edu/humanitiescenter/pdf/The%20Dying%20Animal.pdf",
"According to a report by the\nCornell Lab of Ornithology, yellow-bille... | [
"Primatologist here! ",
"This is kind of a tough one to answer for a number of reasons. ",
"First, any reaction seen is really going to depend on the type of primate and the social system of that primate. In more social species you’re probably more likely to see something interesting than in less social specie... |
[
"Is the gravitational attraction pulling us constantly with the same amount of force in different locations or it differs, what about if you're on a boat in the ocean?"
] | [
false
] | null | [
"It varies by up to 0.7%",
". Some of the variation (0.3%) is not, strictly speaking, due to variation in gravity, but due to the earth's spin creating a centrifugal force which is greatest at the equator. If you want to weight the most, stand on the north pole. To weight your least (on the surface of the eart... | [
"It differs. Gravitation is towards mass, so mass distribution affects the distribution of force in the gravitation field. Same in the ocean. And, of course, celestial bodies affect the sum total of gravitational force you experience."
] | [
"That is what I was looking for and it's what I thought too, makes sense, thank you!"
] |
[
"Is there something like the \"double dabble\" algorithm, for trinary/base 3?"
] | [
false
] | [deleted] | [
"It looks like it could be modified pretty easily. First off, instead of adding three to numbers that are at least five before the left shift, you add six to numbers that are at least ten (taking them to at least sixteen) after the left shift. The end result is the same, but it makes it a bit clearer and makes it g... | [
"Quick note, relized base 3 is probably called ternary, not trinary."
] | [
"Thanks! Very clear explanation."
] |
[
"If a planet is no longer rotating but still revolving around a star, will the planet start rotating again?"
] | [
false
] | null | [
"How does it transfer it's rotational momentum?"
] | [
"How does it transfer it's rotational momentum?"
] | [
"The star's gravity will raise a tidal bulge on the surface of the planet: as the planet moves in its orbit the bulge will become offset from the star-to-planet radius line. The star's gravity then pulls on the bulge, creating a net torque which causes the planet to rotate.",
"It's exactly the same as the usual ... |
[
"Is time discrete or continuous? What would help to indicate that it is one vs. the other?"
] | [
false
] | null | [
"It’s continuous, as far as we know."
] | [
"It's possible that time is discrete on a scale too small to probe experimentally using current technology. Experiments sensitive to phenomena on shorter timescales could change the status quo.",
"I imagine there's no way to prove it experimentally other than to directly show that time is discrete. But even with ... | [
"What would help to support this argument? Is this something that could be testable in theory, and we just don't have a \"precise enough\" way of measuring time as a unit yet?",
"Would this be something more likely to be proven directly or proven indirectly (by eliminating the other possibility)?"
] |
[
"How can you lose members because of diabetes?"
] | [
false
] | null | [
"Diabetes causes problems with the circulation. ",
"The metabolic differences in uncontrolled diabetes, like high levels of glucose and fatty acids in the bloodstream, trigger changes in the cells that line the walls of blood vessels. Over time those walls stiffen, thicken, and contract, leaving much less room in... | [
"Peripheral neuropathy is one of the long-term consequences of uncontrolled diabetes because high blood glucose damage nerves among other things, and people lose sensation in their feet (higher parts can be affected too, but feet are most common) and don't realize when they get an injury -- could be from stepping o... | [
"Another aspect of hyperglycemia is that it effects the capillaries. Unhealthy necrotic growth of capillaries occurs which lead to hemorrhaging of lymphatic fluids and blood with poor oxygen transport leading to tissue damage and infection. That's why exercise is so important for any diabetic. Exercise improves ins... |
[
"Do other elements occasionally fuse in our sun? Elements like Helium, Lithium, etc.? Or is it strictly Hydrogen only?"
] | [
false
] | null | [
"Well, yes and no. The sun gets its energy from the chain of reactions that leads from 4H to 1He. But there are actually several different chains that lead to the same result. It's not just like 4 hydrogen atoms all meet up and the same time and out comes helium.",
"Most of the time you're getting the energy from... | [
"Our sun is a main sequence star. What that means is that it is burning only (with perhaps exceptionally minor deviations) Hydrogen in it's core. Hydrogen is the easiest element by far to fuse, starts fusing the earliest. As a star collapses from a cloud of gas, it's interior heats up and the pressure increases mor... | [
"A much more in depth answer. Thanks."
] |
[
"What exactly is gluon fusion and why is it the primary means of Higgs production at the LHC?"
] | [
false
] | I'm studying the Higgs for a highschool course and I'm more or less just curious as to what gluon fusion is other than just the union of two gluons. As well as why this is used so exclusively at the LHC? If anyone had the time to explain other methods such as proton-proton collisions etc that'd be great. | [
"This is an extremely intricate and complex process. So instead of trying to paraphrase and give you an explanation that probably won't satisfy your curiosity, check out ",
"these",
" ",
"links.",
"They have some good explanations of the process, along with some math. The math may be too over your head, but... | [
"Like ",
"/u/IKinetic",
" said, it's and intricate and complex process. But I'll give it a try. The explanation won't be mathematically rigorous, but it should give you a rough idea. And it aligns with the intuition of an experimental particle physicists (theorists might cringe a bit though, but psh, who needs ... | [
"These are things you learn perhaps at the end of an undergraduate physics major, or at the beginning of a physics PhD program in particle physics, depending on what schools you're talking about. A lot of this knowledge comes from doing research in LHC-related experiments and often not so directly from classes. Man... |
[
"Why do cars make a \"whooshing\" sound when you drive past them, even if they are stationary?"
] | [
false
] | When a car drives past, you can hear a whoosh sound because (I assume) the displacement of the air. However, why would this sound occur when you are driving in a car with your window open, and you pass a stationary car? My friend suggested this was do to the interaction of the displacement of the air with a large, stationary object, but I've heard this sound even from a few lanes over when you wouldn't expect the displacement of air as you drive by to affect the parked car. I'm guessing that this is some sort of echo effect, echoing the sound of my vehicle passing theirs. So, what's the truth? | [
"Its the Doppler effect of the sound that you're making bouncing off the other car."
] | [
"It's just the sound (of the air turbulence around your car) bouncing off the other cars. If I have a noisy brake, for example, I'll notice it more when I've got my window down, drive by a pack of cars, or drive near a high curb.",
"You friend is somewhat right, though. As your car moves, it does displace air, an... | [
"No worries! I have been fooled by much simpler stuff."
] |
[
"Why is the universe Accelerating in expansion?"
] | [
false
] | [deleted] | [
"But one tinier than what we'd expect by a factor of 10",
" and that's just assuming that no Planck-scale physics adds to the vacuum expectation value. So it's a possibility but certainly not the only explanation for the acceleration."
] | [
"That's a good question. If the Universe's energy budget were dominated by normal matter or radiation then yes, the gravity of all the stuff in the Universe acting on the rest would cause it to decelerate. This is why we were so surprised to find that the opposite is happening!",
"So obviously the assumption in t... | [
"Short answer, but i am sure someone will correct me or fill in the blanks, if needed:",
"Back in the day, someone found out that the density of the universe, would tell the shape and the ultimate fate of the universe. They tried to measure the density of the universe, but found that the measured density could no... |
[
"Did the earth form from the Sun \"spitting it out in the form of a meteorite?\""
] | [
false
] | null | [
"All of this is pure insanity. Please disregard that entire paragraph. If you're curious to our best understanding, simply search around for AskScience posts or Wikipedia articles on the formation of the solar system, the sun, the earth, dark energy, meteorites and basic chemistry."
] | [
"That's what I thought...thanks. Now how to break it to him?"
] | [
"Very gently?"
] |
[
"Is there any scientific consensus regarding the longterm effects of smoking marijuana?"
] | [
false
] | [deleted] | [
"The appropriate answer to OP's question is that no, there is no strong consensus on the long-term effects of cannabis use (I avoid saying \"smoking\" because the smoke part is another health risk altogether, and we'll leave this strictly up to cannabis).",
"I certainly agree that there is a lot of promising rese... | [
"The appropriate answer to OP's question is that no, there is no strong consensus on the long-term effects of cannabis use (I avoid saying \"smoking\" because the smoke part is another health risk altogether, and we'll leave this strictly up to cannabis).",
"I certainly agree that there is a lot of promising rese... | [
" comments as of this post.",
"Very few scientific answers. Even fewer cited ones. And a lot that list cited benefits but not the downsides.",
"Basically, IntoTheMystic, you're going to have to go to a completely different website because this one is too biased to ever be a reliable source of information.",
"... |
[
"How cold would it have to be to slow data packets transmitted over wire? Does temperature even have an effect on this?"
] | [
false
] | My friend and I were joking about the cold weather in Canada. I remarked that it was "so cold packets were freezing and ping was timing out." While humorous, it got me thinking -- is this possible? How is our data transmitted over wire? Can it be affected by temperature? If I cooled a section of the wire to just above absolute zero -- what would happen to new data as it flows into that area? Would it just be a giant traffic jam? | [
"Many metals become more conductive at lower temperatures, which would reduce the voltage or wattage requirement in order to transmit.",
"Although not all materials become superconductors when cold, all superconductors must be cooled to be superconducting.",
"So, no. There would not be a traffic jam. It would m... | [
"At absolute zero, the average velocity of an ideal gas, solid, liquid, whatever - becomes zero. When you get really really really close to absolute zero, strange stuff starts to happen. But for all intents and purposes, electrons move from one atom to another. ",
"Imagine atoms are like pingpong balls in a b... | [
"This is a good question! I know everybody likes to say \"electricity moves at the speed of light!\", but this is not quite true and it leads to interesting contradictions like the one you have mentioned here. Electrons in an ordinary metal conductor do not move at the speed of light, they move at a very slow spe... |
[
"What makes viruses only survive in water droplets, on surfaces, or in air? What about temperature?"
] | [
false
] | In this video this doctor says the virus can live on a surface for 9 days, does that mean that surfaces must have moisture on it? Can a virus live in anything that's fat, like oil? What makes other viruses survive without water droplets? (What sort of viruses are airborne?) What makes the HIV virus only survive in blood? Can the HIV virus mutate to live in water droplets? | [
"Biological things are quite delicate, and there are many things that can damage any biological matter, for example, oxygen, UV rays, high temperatures, low temperatures, high salts, low salts, the list goes on. The reason why certain viruses only survive in water droplets or blood depends on how delicate the viral... | [
"I agree that oils can denature capsid proteins, dehydrate them, but the preservation in a micelle doesn't make sense to me.",
"I think viruses can be preserved in a micelle if its surrounded by water and that tiny water droplet gets trapped in a micelle. Though this happening is pretty unlikely so my answer was ... | [
"Can a virus live in oil? That's a good question and I can only give an educated guess, which is probably not.",
"Could you give an update to your comment if you've come across any new information?",
"I agree that oils can denature capsid proteins, dehydrate them, but the preservation in a micelle doesn't make ... |
[
"A black-body with a temperature above 8,000k appears blue. Is it still blue at 100,000k or more?"
] | [
false
] | Neutron stars appear white, and they have temperatures above 100,000 kelvin. What's the reason for this? | [
"Since a 100,000K star is outputting approximately the same amount of each color of light, it appears white.",
"This is wrong. The problem is that at 100,000 K, the spectral energy distribution is so strongly dominated by incredibly short wavelengths in the ultraviolet/X-ray region that you don't have the dynamic... | [
"I'm not sure, and unfortunately the statement is unsourced. I see a number of people in discussions of this making the same argument I did, but that seems to be naive. ",
"If we consider the ",
"ratio of red to blue light emitted",
", then blue light does continue to be about an order of magnitude higher f... | [
"We have ",
"Planck's law",
" to describe the light output of a black-body at a particular temperature over different wavelengths."
] |
[
"I have an introductory Physics Question..."
] | [
false
] | I'm not sure if this is the right subreddit for this, so let me know if I'm in the wrong place. We are doing the physics unit on Energy, Power and Work, and I am having some trouble figuring out how to work a pretty basic problem. I have linked the problem and my attempted solution below. If anyone could explain how to do this problem, it would really help me understand the rest of the unit... Thanks everyone! | [
"In the future you might also try ",
"r/homework help",
" for this kind of question. "
] | [
"You're attacking this problem the wrong way. Instead of thinking about forces, think in terms of energy. Moving the car forward at a certain speed movies it upwards at a related speed, which can be found using the angle. Using the formula for gravitational potential work=mass*9.8*height, you can then relate its up... | [
"I am sure that instead of energy, you meant power."
] |
[
"a question involving physics"
] | [
false
] | i have a question in regards to ballistics... im looking for an equation(or even a site that i can go to) that i can imput the mass of an object, the speed of said object, and other certain variables... like density wind and thickness of target, to get all the projected paths... NO I AM NOT AN ASSASIN(assasins would know shit like this) im just looking for a computer model im trying to put together | [
"If there is no wind, you can solve this directly with the kinematic equations (which I can explain if you like).",
"If there ",
" wind, it's easiest to write a computer program to solve this really. You mentioned computer model - are you comfortable with programming in any one particular language? I can teach ... | [
"Can I ask for clarification on what you're looking for with \"all projected paths\"? What are you projecting exactly? Would it be correct to rephrase your question as \"For a target of a certain size in a certain position, what are all the points I could shoot it from (for a certain muzzle velocity and drag force)... | [
"Well, if there's no drag, then it's just a whole bunch of parabolae.",
"If there is drag, you're going to have to simulate a whole bunch of firings. Each of these will make a line, and you can plot these.",
"For each shot, you start with the initial position & velocity of your projectile. This is six numbers, ... |
[
"How would the sky look if viewed from a planet closer to the center of our galaxy?"
] | [
false
] | I was just wondering that since the center of our galaxy seems at least to us pretty bright, would it also seem as bright if viewed from a planet orbiting some star there? Or are the distances between starts there still long enough that the the sky would look something resembling a little brighter version of our own night sky? | [
"Being closer to the inside of the galaxy, the biggest effect would be that the white band that makes up the Milky Way would be thicker and extend further around, until once you are fairly deep in it would appear to wrap all the way around the sky (although you'll still a lot of individual stars, since only the mor... | [
"There would still be a day/night cycle provided the planet you were on was rotating sufficiently.",
"The night sky would appear brighter, but still recognizably night and not as bright as day."
] | [
"Would the stars at the centre of our galaxy be so close to each other that the night sky a would actually be lid up by other nearby stars? So would the be a \"night\" at all?"
] |
[
"Is there any potential for non-random genetic mutation? Is feedback driven evolution possible?"
] | [
false
] | Consider if the legs of newborns were amputated at birth. Could this lead to human populations without legs, with stunted, malformed or even huge legs? Intuitively, it seems there might be evolutionary changes relating to traits which provide improved fitness given lack of legs. Leg related selection would be impossible (given you can't tell what your mate's legs were like), unless leg traits are related to, for example, arm traits that are selected for (e.g. huge, long arms, which would be useful without legs, might be associated with huge, long legs, or smaller legs, or whatever). But is there any potentially direct mechanism for altering a genetic trait passed to your offspring in a behaviorally moderated fashion? In short, is there any way genetic traits unrelated to any significant selection process can evolve as a result of behavior, or will they only change due to an association with other selectively significant traits? | [
"i know, but it was related to what the OP was asking. i thought maybe reading the article could have answered his question better than me just saying \"not really\" in response to his question."
] | [
"It seems to me that there are at least two questions here:",
"Consider if the legs of newborns were amputated at birth. Could this lead to human populations without legs, with stunted, malformed or even huge legs? ",
"Yes. Absolutely. For the same reason that cave dwellers are born without working eyes.",
"h... | [
"this could be of use to you:",
"http://en.wikipedia.org/wiki/Lamarkism",
"also this:",
"http://en.wikipedia.org/wiki/Epigenetics"
] |
[
"Why is that both nuclear fission and nuclear fusion release energy? Shouldn't one release energy and the other absorb energy?"
] | [
false
] | null | [
"The reason is that iron is the most stable element. ",
"Why then is iron the most stable element? When lighter elements combine, the net attraction between the nucleons due to the strong force exceeds the net repulsion due to the Coulomb force. Once the nucleus starts to be too big, however, the attractive fo... | [
"They do. Either fusing element A and B into C will produce energy and fissioning C int A and B will consume it or vice versa. But people are interested in using nuclear reactions to release energy, not consume it, so they only talk about fusing light elements and fissioning heavy ones, which are the reactions that... | [
"Fe56 is the most stable element and nuclear reactions that move closer to this point release energy. Fusion releases energy until iron is produced, at which point energy must be added back in to produce heavier elements. Fission is the opposite, releasing energy as heavier elements are split until iron is produc... |
[
"Is there a genetic disease where the heterozygote has more severe disease symptoms than the homozygote?"
] | [
false
] | So we hopefully know that people can carry some genetic mutation as a heterozygote and have minimal (or no) symptoms, but potential offspring who are homozygous will then show the associated disease with worse symptoms, this is common. But I wonder if there are examples of genetic diseases where the heterozygous condition is actually more severe than the homozygote? Say if a single mutant allele incorrectly activates some pathway relative to wild type, whereas in the homozygote this creates such a large change that the cell responds and the net effect is minimal? Or if two different protein variants interfere with each others’ function, whereas again this potentially does not occur in the wt or homozygote? This could be a loss of function or gain of function effect on the protein. I am not thinking about sex linked genes, only autosomal, or compound mutants where the other allele is affected by a second variant. | [
"Yes; the best studied mechanism for this is cellular interference. ",
"PCDH19 is the classic human disease example. It's a protocadherin (cell surface protein that affects migration, signaling, etc) on the X chromosome. When both normal and abnormal PCDH19 is present (XX heterozygotes) affected individuals have ... | [
"Maybe. ",
"In sheep and pigs, there’s a complex scenario (“polar overdominance”) in which only heterozygotes with a particular mutation show the phenotype:",
"A single nucleotide polymorphism in the DLK1-DIO3 imprinted gene cluster alters gene expression … muscle hypertrophy only occurs in heterozygous animals... | [
"A bit indirect, but some forms of achondroplasia are so severe that homozygotes are incompatible with live birth, and thus heterozygous (or homozygous would type) are the only observed.",
"A better example: ABO blood types in terms of blood contaminagion (whether available acceptable blood types, or maternal-fet... |
[
"Does relativity have any effect on temperature similar to how length becomes contracted and time gets dilated?"
] | [
false
] | null | [
"So first to clarify your question. Temperature is a number a number that becomes useful when we are talking about a box of particles, in fact only if the box of particles is in something called thermal equilibrium. By saying a box of particles is at temperature T we are really saying that the distribution of parti... | [
"An interesting fact is that the EM blackbody radiation spectrum of a cool object looks exactly like a redshifted spectrum from a hot object, and that of a hot object looks like a blueshifted version of a cool object. Which is to say, if you measure temperature with one of those temperature-sensor guns you won't kn... | [
"Actually the OP could be thinking of a third case: the fact that time dilation shifts the velocity distribution of a box of particles. In other words is temperature a relativistic invariant, and if not, what is the transformation. This is something Einstein and Planck attempted to work out in 1907, arguing that te... |
[
"Cysteine to help metabolize the highly toxic 'acetaldehyde' that accumulates during a night of drinking."
] | [
false
] | Dear Science, I am wondering if you'd care to comment on the proposal that taking cysteine supplements while drinking alcohol can have a positive effect on the breaking down of the acetaldehyde that accumulates when one metabolizes alcohol. I have heard that people who suffer with the particular enzyme deficiency that leads to the 'Asian flush' while drinking have reported some success with the use of cysteine (paired with vitamin c). However, such people have also reported success, I believe, with taking Zantac or Pepcid AC. Since reading this article I have been taking cysteine and vitamin c very diligently whenever I drink. I started the process originally not because I would suffer any sort of Asian flush reaction, but rather that alcohol tended to make me feel sick to my stomach every morning after drinking (but, oddly, never during the actual night of drinking). Is there any credence to this claim? The rat test described by the article is interesting (that it protected rats from dying after being administered lethal doses of acetaldehyde. I do find it seems to help with my morning-after-drinking nausea, but I am also open to the possibility that I am just building up a tolerance for alcohol. Thanks science <3 | [
"hangover causes",
"I'm not sure the cysteine and vitamin C are actually helping. The wikipedia article seems to say that most hangover symptoms are caused by a decline in NAD+ concentrations, which is caused by alcohol dehydrogenase and acetaldehyde dehydrogenase activity. Water and food, however, do help."
] | [
"I thought the same thing. Because of the use of acetic acid as an energy source from the oxidation of alcohol, your blood sugar crashes due to low glycogen release from the liver. This, coupled with dehydration, makes you feel hungover.",
"The old wolf-down-a-poutine-and-drink-three-glasses-of-water-before-pas... | [
"If you really wanted repeatability in your experiment, you might try Steel Reserve instead of the Natty. Worst hangover/fl. oz. ratio of just about any beer."
] |
[
"Is there anything capable of withstanding direct contact with lava?"
] | [
false
] | So, is there anything capable of withstanding direct long-term contact with lava? Like some type of metal or something? | [
"You might want to see ",
"my thread here",
" about some of the cool things (pun intended) we do with lava (like ",
" in lava, ",
" lava, etc). You will see shovels, gloves, etc - all handling lava.",
"People are always surprised at how lava does NOT just melt everything. Toss a rock onto a surface flow ... | [
"If you look at the 3rd picture on my linked post: ",
"http://i.imgur.com/vlbCP.jpg",
"Look at the lava on the ground - I had just lifted that up to show some tourists, and dropped it because I held it for about 20 seconds or so and it was getting pretty hot. Look at my glove and you can see some lava stuck to... | [
"With the temperature of lava (That is, above ground and not magma, which is below ground) being between 1300 - 2200 degrees F, any alloy or material with a melting point above that will withstand contact. Magma can reach much higher temperatures in subduction zones however. ",
"Here",
" are some melting poin... |
[
"How did the moon landing spacesuits survive the ridiculous temperatures?"
] | [
false
] | I’m not a conspiracy theorist I just need to know | [
"The short answer is that astronauts survive the cold with layers upon layers of insulation and survive the heat by reflecting most of the light that they come into contact with. That's why spacesuits are bulky and also white."
] | [
"Internal tubing and a pump flow’s coolant between the outer space suit and the astronaut."
] | [
"Thank you, I was hoping someone would provide a more technical answer"
] |
[
"How much of a threat is space debris?"
] | [
false
] | [deleted] | [
"The short answer is yes. It is a Threat. ",
"Is it overstated by the media? Yes and no. ",
"Kessler syndrome is a real worry, There is a critical mass that needs to be floating up there before that happens though. NASA , ESA, CNSA and everyone with a space agency have their predictions about that, since they t... | [
"But that debris also stays put in its orbit. Except for the ",
" small pieces, we know where most of them are. For the most part, the odds of getting hit by one without even seeing it coming are minuscule.",
"But yeah, nobody wants to be responsible for making more. Launches have gotten good at ensuring most o... | [
"But that debris also stays put in its orbit",
"Debris in LEO will eventually de-orbit in a reasonable timeframe, more or less. Geostationary satellites are boosted to higher orbit called the graveyard orbit at the end of their lifespan, and there they will stay for millennia. However, the orbit itself is also mu... |
[
"What is the difference between quantum entanglement and a classical analogon? (see description)"
] | [
false
] | Let's say we generate a pair of entangled photons and measure the state of one of the photons. It is often said that the other photon then immedietaly takes the opposite state, which is the "spooky action" that Einstein described. Now lets say I have two classical objects, one white and one black and throw them blindly in opposite directions. I don't know which object I threw where but if I find one of the objects and see its color I immediately know the color of the other object. Where is the difference to quantum entanglement? Why is quantum entanglement so spooky? Is it just in the maths or is there some way to describe it visually? | [
"What you're describing is not an entangled state, it's just a mixed state. There are mixed states in both classical and quantum mechanics, but entangled states are purely quantum; there is no classical analog."
] | [
"Whether the states of the two objects count as entangled depends on whether or not there is (or has every been) any record, anywhere else in the universe, that would let one reconstruct their states (i.e., whether the states have been \"observed\"). For objects large enough for a human to interact with, the answer... | [
"The difference is that in the classical example you already know that one is white and one is black. Their colours were set prior to the measurement, you just don't know which one is which (this is called a \"mixed state\"). In QM, the states are not individually defined prior to the measurement, there is just a s... |
[
"What determines how much of an ingredient you have to add to a dish in order for the dish to have a noticeable change in flavor?"
] | [
false
] | For instance, you usually see chefs on shows saying add a tiny pinch of salt or pepper into a dish. But does that tiny pinch really make a difference in the overall flavor of the dish? I'm not sure how much of a difference an couple extra grains of salt or sugar can add to a dish's flavor. How much salt, sugar, pepper, whatever do you have to add in order for the dishes flavor to change? What determines this noticeable change in flavor? | [
"Taste is quite complicated so it is not always a linear 'more of X = stronger flavour', although that will generally be true if you are talking about something simple like adding more sugar to water.",
"It also depends on what the other flavours in the dish are already. For example if you over brew your coffee i... | [
"The factor that determines the amount of spice required to change the taste of a dish is the concentration of the spice. Many spices are concentrated to the extent that consuming the raw form will overload the sensory receptors in your taste buds, and cause an unpleasant response (e.g. the so-called cinnamon chall... | [
"Once you learn to cook and add certain amounts of salt and pepper you can and will taste the difference, I'd suggest cooking the same meal using different measurements to understand this concept as it is the only way to learn it it. "
] |
[
"If the universe (\"space\") is expanding (and we know that by observing the red shift phenomena of objects moving away from us), why don't we observe/perceive the same thing within our own solar system?"
] | [
false
] | null | [
"Hi! We have a bunch of questions on ",
"the universe expanding",
" in our astronomy FAQ, including a couple about the solar system and local effects of gravity. There may be similar topics in there that interest you, too. Check them out and let us know if you have more questions!"
] | [
"Thanks. I wasn't sure whether to ask my question in the Physics or Astronomy section. I'll take a look over there.",
"For my future reference, I had read the recommendations for asking a question, but wasn't sure if I should have submitted it through a moderator or not. Should I submit future questions throug... | [
"Nope, you're fine to just submit things. Sometimes submission rates go through the roof and we get backed up, so posts can end up buried. If you submit and a post doesn't show after a couple hours, let us know and we'll check into it right away.",
"We don't let similar questions out too frequently because our pa... |
[
"What is the likely mortality rate of COVID without any medical treatment?"
] | [
false
] | I’ve heard about how lots of people die when there isn’t oxygen available for COVID patients in the icu. Like what happened in Egypt a few months ago. | [
"We can use death rate from overwhelmed hospital data in the early stages of outbreak as a proxy. In Italy, they had an uncontrolled outbreak in q2 2020 that used up the ICU capacity. With ventilators, 30% admitted died. Without ventilators, 60% died. About 10% of infected people got admitted, with a large age ... | [
"Your question heavily depends on the demographic you are talking about, first of all. Young people with no health problems have about a 0.03% fatality rate. As a human ages, gains weight, and encounters other health problems, that risk dramatically rises. COPD, a disease that typically results from smoking and dam... | [
"48% of Covid-19 deaths in India, up to a few months ago, were younger than 60. This is not explained by its relatively younger population.",
"https://science.thewire.in/health/india-covid-19-mortality-comorbidities-age-health-ministry/",
"This is seen in most countries in the developing world, several reasons ... |
[
"How is body air volume effected by water pressure with free divers? As opposed to an open system with scuba divers."
] | [
false
] | I understand the concept of air and nitrogen/oxygen levels in scuba diving but that's an open system. If a diver holds their breath at the surface and dives down to 20 m do they now only have a quarter of that air usable in their bodies even though it's a closed system? The record is around a 100m is the divers body working with 1/1024 of the original air they got at the surface? I am not sure if I am explaining the question correctly but any light that can be shed on this would be greatly appreciated! | [
"You just have to remember a very simple equation:",
"pV = nRT",
"When you take a breath of air, there is a specific number of air molecules that enter your lungs at a specific temperature (~ body temperature): that's the \"nRT\" side of the equation.",
"When you dive down, the number and temperature of the a... | [
"I am having trouble believing the idea that your lung surface area decreases by so much.",
"In an ideal (one whose sides are lines or planes of zero width) geometrical shape, you can keep the surface the same and reduce the volume essentially to zero.",
"For example, the shape which results if you pinch a sphe... | [
"You'll note that because we are talking about ratios of before/after area, we can highly generalize the problem. So when I say that surface area is ",
" to some characteristic length scale ",
" an example might be the surface area of a sphere, which is ",
" = 4pi x ",
" in which the characteristic length ... |
[
"How does ionization state affect radioactive decay rates?"
] | [
false
] | I was taking a stroll through Wikipedia and came across this: Technetium is a chemical element with the symbol Tc and atomic number 43. It is the lightest element whose isotopes are all radioactive; ...So there is one isotope of Technetium that is or is not stable depending on its ionization state. Is it normal for ionization state to affect the half life of radioactive isotopes? How does it work? And is that useful information or just a curious little detail? | [
"Certain kinds of nuclear decays involve the atomic electrons. One example is electron capture, which is similar to a beta",
" decay, but instead of producing a positron, the nucleus absorbs an electron. This can happen spontaneously in atoms because there are bound electrons available. Technetium-97 in the groun... | [
"That is really interesting. Thank you. But I assume you would never realistically see it stripped of all 43 electrons, right? I mean at that point it would be so highly charged it would steal electrons from basically everything, right?"
] | [
"Accelerators can strip all electrons from all elements they can accelerate. The LHC routinely creates bare lead nuclei, stripping all 82 electrons from the atom. Fully ionized uranium is common as well.",
"There are just a few cases where the stability changes based on the electrons. There is also one nuclide th... |
[
"Are there glaciers on Mars' polar regions?"
] | [
false
] | null | [
"Mars has a southern polar icecap, which consist of water ice and carbon dioxide ice which shrinks and grows with the seasonal cycle. It has more in common with the antarctic ice cap, but without marginal spreading. Growth and shrinkage are controlled by sublimation. There is no northern icecap."
] | [
"...and I'll post it again. Mars does indeed have a northern icecap.\n ",
"http://en.m.wikipedia.org/wiki/Martian_polar_ice_caps"
] | [
"I recently talked to a planetologist who examines mega dunes on the northern ice cap on mars. She said it's still controversial whether there are flowing glaciers on mars since it is hard to trace movement, but the northern ice cap exists and follows seasonal changes, although small.\nThe northern Ice cap is also ... |
[
"Is this the right intepretation of Schrodingers cat?"
] | [
false
] | I feel this is a very misunderstood experiment, so ill try to explain it, and you guys can correct me in case Im wrong. Basicly the first misconception I see is that if you put the cat in the box, it is no longer observed. This is a misunderstanding of what 'observed' means in the quantum world. It does NOT mean that a human or other animal actually has to see the cat. It means an interaction with matter (or with the electrons that are 'floating' outside matter) or a loose electron or photon. For example in the double slit experiment, a photon is observed and collapses from the superposition if it hits the screen at the other end. The difference between being observed by a photon or by matter (the screen or 'end' destination) is that if a particle small enough is observed in midair by a photon it now behaves as if it was a particle all along. But if it is not observed in 'midair' and has the chance to hit the screen it has been a wave all a long. So it does not matter wether you put a box around the cat or not. Because if the geiger counter goes off, and the device to kill the cat is activated, the super position collapses. This happens before the cat dies. The moment the geiger counter is activated is also the moment the observation takes place. This is not my thought, but was Niels Bohr's observation fwiw. I think this is also the origin of the multiverse theory? Because the time of decaying, and the subsequent observation is truly random. So you cannot predict when the cat will die. It could be after 5 minutes, or after 20 minutes. It is TRULY random. Only the Radioactive substance on the microscopic scale does. And this is why physicists think that every bit of time on that time line of decay, a new universe splits off. So if the cat dies exactly after 20min , then you are in the universe where the cat dies after 20min. But there is another universe split off 15min ago where the cat died after exactly 5 min. And another one where the cat died after 7.23 min and one where it died after 9 min and so on. This seems to be an attempt by physicists to make the true randomness of quantum mechanics deterministic again? This is probably where my understanding ends :) . Thoughts? | [
"I feel this is a very misunderstood experiment, so ill try to explain it, and you guys can correct me in case Im wrong.",
"Among lay people yes, but not among most physicists.",
"It does NOT mean that a human or other animal actually has to see the cat. It means an interaction with matter (or with the electron... | [
"With the exception of gravity, which isn't described in quantum theory, any interaction between two molecules could be considered observation. What's necessary for \"observation\" is that the interaction entangles the two molecules, so that now something you can measure about molecule 1 is correlated with somethin... | [
"Would any type of interaction between two molecules be considered observation. Like two hydrogen next to each other would feel gravity, electric, magnetic, and many other forces between each other"
] |
[
"How do we know how many protons are in an atom's nucleus?"
] | [
false
] | How do we know how many protons are in the nucleus of each element's atom? Do we have a way of viewing things that can magnify more than electron microscopy? If you can provide your source, that would be much appreciated, but it is not required. Thanks! | [
"Historically, first you had Berzelius and others making accurate measurements of (relative) atomic masses in the early 19th century, and in the late 19th century you had Mendeleev coming up with the periodic table by ordering the elements by a combination of their mass and properties. By that time they still didn'... | [
"That's completely wrong, everything you just wrote. Atoms don't have to be neutral at all times. Second, you ",
" tell in how many electrons there are in an atom from its properties in any straightforward manner, and they had neither the calculating power nor the quantum mechanics required to do such calculation... | [
"I would just like to add, the actual atomic numbers and which elements were still missing was done by using x-ray spectroscopy. The 1s electrons basically feel the full charge of the nucleus and the energy of an x-ray emitted when an electron from the n=2 level falls to the n=1 level is proportional to (Z-1)",
... |
[
"Are there any differences in penis size based on race and nationality?"
] | [
false
] | null | [
"Hi Randomthrowayawayman 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... | [
"Human Body."
] | [
"Thank you for your submission! Unfortunately, your submission has been removed for the following reason(s):",
"/r/AskScience",
"For more information regarding this and similar issues, please see our ",
"guidelines",
"If you disagree with this decision, please send a ",
"message to the moderators."
] |
[
"How much do our organs move?"
] | [
false
] | In addition to the heart and lungs, what's the extent and type of movement of our organs like the intestines, stomach, kidneys, liver, etc.? | [
"Each organ has its own little sack, and that sack is embedded inside a larger sack, so imagine everything’s pretty organized on where it is based on the sack system, with tissue allowing for some movement (like a few inches in any direction temporarily) but still having central locations for everything. Also some ... | [
"So wait, the exterior of the organs that we see and are familiar with is basically a sack for the organ itself? With the exception of livers and kidneys since you said they don't move?\nSo are the intestines, for example, in a sack on their own or with other organs from the digestive system? And if they're on thei... | [
"So for example, if you see a heart inside of someone, it will be surrounded by this thing called the pericardium. When you look at images of a heart, the pericardium will typically be removed or reflected to see the actual heart. The pericardium is the sac itself, it is multilayered and basically provides a little... |
[
"What's the basis of NMR spectroscopy?"
] | [
false
] | I've been doing some reading online and from what I've seen, there are two different explanations of NMR spectroscopy. One implies that the magnetic dipole moments can flip when hit by radio waves, and when they flip back, energy is emitted in the form of electromagnetic radiation. By analysing the emitted waves, we can determine their source, etc. The other explanation is that the sample is hit by a pulse, causing the dipoles to precess, and it is this precession that is used to determine the isotope in question. My question is, which of these explanations is correct? Is one a simplified version of the other? Or are both correct, and are simply different techniques for sample analysis? | [
"They are both kind of half right, but the precession is more right.",
"In an NMR, the large magnetic field creates an energy difference between the two different spin states of a nucleus (spin up and spin down). The short radio pulse creates a superposition of the spin-up and spin-down states (a \"coherence sta... | [
"The alternation between being more \"spin up\" and more \"spin down\" creates an oscillating magnetic field which is picked up as an oscillating voltage.",
"That is not quite correct. The oscillating voltage is induced by the precission of the spins. Spin up and spin down induce voltages of the opposite sign and... | [
"Thanks, your answer was really helpful! Just to make sure I understand this correctly though, is the only signal we're interested in, a result of the oscillating voltage? Photons emitted during transition from one state to the other are not the source of our data?"
] |
[
"If we are constantly breathing in pathogenic microorganisms, why don't we get sick more often?"
] | [
false
] | I understand that microorganisms are everywhere. Therefore when we breath, we must breath them in. Why don't we get sick? Is it because the ones we breathe in aren't pathogenic? Or is it that the amount of pathogenic microorganisms is small and our immune system can handle it? As opposed to eating rotten food that has a higher concentration. Would that mean that pathogenic bacterias's effect is dose dependent? | [
"Our immune system is always working to fight off dangerous bacteria. I suppose when you say sick you mean why don't we get syntoms like fevers and pains every day from this fight, right? You only get symtoms when the immune system is not strong enough to fight off all the bacteria there is (causing an infection, f... | [
"Virtually every pathogen you ingest will be located and dealt with by the innate response of the immune system before you ever notice any symptoms at all. This does not qualify as infection - it's simple routine entry and clearing of pathogens. The cells responsible for this (Primarily Neutrophils & Macrophages)... | [
"I am a med student but very early in the course in a country where we get into med right after high school, so don't trust me very much, I wouldn't. I knew some things by head but I made some quick research in the internet to make sure before answering your question. I can send some links over. \n",
"https://www... |
[
"What is the minimum time needed to produce a verbal response?"
] | [
false
] | [deleted] | [
"This is very situation-dependent. In a lexical decision task (people see a bunch of words pop up on the screen and have to answer y/n to \"is this a word or not?\") the usual low-end of accurate response times on real words is about 200-300ms. In situations like this people are just reading a single word, making s... | [
" the more similar the non-words are to real words.",
"Does this include following common patterns like using real affixes or avoiding weird rhymes like /aUm/?"
] | [
"Yes, phonotactically acceptable non-words will take longer to identify as non-words, and non-words with real morphology will too."
] |
[
"Noob question: Do the fundamental forces obey thermodynamics?"
] | [
false
] | First off I'm sure the answer is yes. I just can't wrap my hand around magnetism. It seems to always have it's magnetic properties so how is it still obeying the laws of thermodynamics? | [
"For clarification: what thermodynamic principles do you think magnetic fields violate?"
] | [
"An object being attracted to an object by as magnet is the same as a rock falling downhill. No violation."
] | [
"I think what I'm relally wondering is where is the energy input for the magnet?"
] |
[
"Why does a glass of water left for a while, have tiny bubbles on the inside of the glass?"
] | [
false
] | I guess this depends on what type of water you drink, but I've seen it in both Norway and Denmark. When I have a glass of water (tapwater) before I go to bed for example, but don't drink it all, the next day the inside of the glass is packed with tiny bubbles. And it seems like the longer it is left untouched, the bigger the bubbles get. Why is that? | [
"This is due to the temperature dependence of the solubility of gases in water. Colder water is capable of containing more dissolved gas (air) than warmer water. In the case of your tap water, the dissolved gases in the water reflect the two major components of the atmosphere: nitrogen and oxygen. Since you are ... | [
"This is correct, you are talking about the growth of the bubbles but the part you are missing is the formation of the bubbles on the glass. Bubbles (or crystals if the water were freezing) generally form on an imperfection or small radius object such as dirt or dust. This is the process of nucleation. Combined, t... | [
"Not quite correct.",
"Yes, nucleation of crystals requires a solid seed, a piece of dust, a solid/liquid interface.",
"But nucleation of bubbles requires a vapor seed, a gas/liquid interface. Bubble nucleation involves microbubbles. In glass containers, the \"imperfections\" are actually pockets of air trap... |
[
"Why does a steady stream of water break up after some airtime?"
] | [
false
] | null | [
"The phenomenon is known as ",
"fluid thread breakup",
". The idea is the same as why water on a glass surface prefers to bread - water prefers to minimize its surface area to other fluids or surfaces. So if you dip your finger in water and drag it across a glass surface, initially you may have a long, continuo... | [
"Going deeper, fluid is usually described in three manors: laminar, semi-turbulent, and turbulent. You know how if you turn on a faucet really slowly you get a stream of water that looks perfect and almost non moving? This is laminar. The paths that the molecules are following is very uniform. As gravity, air resis... | [
"I think this one is the answer you're looking for: ",
"Plateau-Rayleigh instability."
] |
[
"Can you identify/separate two mixed blood samples?"
] | [
false
] | If you mix two blood samples in a single vial, would you be able to identify that two individuals' blood had been mixed in a single vial? Could you isolate a single individual's blood or separate the mixture again once mixed? Could you identify from which two people the blood came from, or would mixing the blood prevent a forensic analysis like this? Thanks for the help! | [
"The red blood cells could, yes. As long as they are different blood types. This is based on the different antigens they present that make up the different blood types. Theoretically, you could create antibodies that bind each blood type individually, and tag them with a unique fluorescence. Cell sorting relies on ... | [
"You can do DNA analysis on the blood and tell that the blood is from two people. There is usually DNA floating around in the blood.",
"They perform some fetal genetic tests that way. You just take a sample of the mother's blood and you'll see two types of DNA in there, her's and the unborn child's."
] | [
"If they are of different blood type, cell sorting chromatography can tell you how many different blood types are present. If they are the same blood type, you would have to do DNA analysis to identify the number of individuals. This is done via SNP's. RBC's theoretically do not carry DNA, as they are enucleated. B... |
[
"I know that burning wood is a combustion reaction; is there anything different about the chemical changes going on in a glowing ember vs. a visible flame?"
] | [
false
] | null | [
"Yes. A glowing ember is an example of combustion happening via surface reaction. In charcoal, it is oxygen reacting directly with solid carbon. Visible flames are generally created by gaseous fuel that was either a gas to start with, like propane, or was vaporized by the flame's heat, like candle wax. Surface ... | [
"If we want to get technical, the combustion reaction of oxygen with solid-phase fuel (with no flame) is called \"",
"smoldering",
"\", while gas-phase fuel reacting with oxygen produces flames. I'm not sure if there's an equivalent for direct combustion of a liquid; most flammable liquids have a high vapor pr... | [
"Did you mean to make a top-level reply?"
] |
[
"Is there a non-geometric equivalent to Einstein's theory of general relativity?"
] | [
false
] | If I understand correctly, the geometric approach is what makes this theory so elegant. I wonder if there exists a theory that takes a non-geometric approach and agrees with the general theory of relativity on all (or most) findings at the expense of simplicity. Define "non-geometric" in specific terms? | [
"The short answer is yes. In the first half of the 20th century, we came to understand all the non-gravitational forces in terms of ",
", with the quintessential example being the electric and magnetic forces. In fact, it wasn't just the forces that came to be described this way, but the matter. Field theory came... | [
"This tensor field couples the same way to all matter, so there's no equivalence principle violation."
] | [
"It haven't read the paper in complete depth, but they seem to be saying that theories which are not \"purely metric\" have a problem with the strong equivalence principle. For example, a scalar-tensor theory like ",
"Brans-Dicke",
" which has the metric interacting with a scalar field.",
"The formulation des... |
[
"What digital synthesis techniques were used to originally create \"Chiptune\" sounds?"
] | [
false
] | I've been playing around with which features (among other things) several digital synthesis techniques, among them FM Synthesis, Additive Synthesis, and a few others simply listed as the type of sound they produce ("String", "Buzz" and "Noise"). Given the computational limitations of early computers and videogame systems, I was wondering, what techniques were the soundchips were actually using to create the sound? | [
"Generally chiptunes consist of basic waveforms, such as sine waves, square waves and sawtooth or triangle waves, and basic percussion, often generated from white noise going through an ADSR envelope or PCM samples.",
"It's a simple wave or static, followed by modifications. For instance, increasing or decreasing... | [
"I'd love more detail. Especially if you have any insights on how I might duplicate this sort of modulation myself."
] | [
"Sure, dude! I started writing chiptunes around 4 years ago but I've pretty much dropped out of the scene and moved onto experimental beat/bass-driven stuff.",
"There are so many ways to pull off chiptunes anymore. If you ",
" want to duplicate stuff well, or begin writing your own look into some trackers. ",
... |
[
"How does the Fermi Temperature exist if the temperature is reliant on the system being equal to zero kelvin?"
] | [
false
] | Hey guys, from my basic knowledge of Physics the Fermi Temperature is Tf = (Ef)/kB. I know that the Fermi Energy is found when the system is at zero degrees kelvin, such that there is no thermal energy, but how is it that there IS in fact a very high temperature that the electrons are actually at (usually 40k K). A follow up question is if there is a different temperature for each energy level (E = kB*T), why do they not equilibrate? I know these are probably pretty silly questions but I am not able to kind them online. Thanks | [
"My earlier comment was more confusing than it needed to be -- apologies for that. The Fermi temperature is the temperature at which average thermal energy is same as the quantum mechanical Fermi energy.",
"So when you calculate the Fermi Temperature, you aren't calculating an actual temperature of the system -- ... | [
"I listened to that last bit and I couldn't make sense of it...",
"Perhaps another way to think of the Fermi energy / Fermi temperature is like this.",
"Fill up the Fermi sphere with all your electrons in the solid. Now, pick one of the electrons right at the Fermi level, and remove all the other electrons. Thi... | [
"All the electrons in a solid are still fermions and so they all can't pile up into the lowest ground state with |k| = 0. This means some of them will be at a higher energy state than others. The electron in the highest energy state will be at the Fermi level. It has a corresponding wavevector and a corresponding t... |
[
"Ask Anything Wednesday - Economics, Political Science, Linguistics, Anthropology"
] | [
false
] | Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Do you have a question within these topics you weren't sure was worth submitting? Is something a bit too speculative for a typical post? No question is too big or small for AAW. In this thread you can ask any science-related question! Things like: "What would happen if...", "How will the future...", "If all the rules for 'X' were different...", "Why does my...". Please post your question as a top-level response to this, and our team of panellists will be here to answer and discuss your questions. The other topic areas will appear in future Ask Anything Wednesdays, so if you have other questions not covered by this weeks theme please either hold on to it until those topics come around, or go and post over in our sister subreddit , where every day is Ask Anything Wednesday! Off-theme questions in this post will be removed to try and keep the thread a manageable size for both our readers and panellists. Please only answer a posted question if you are an expert in the field. . In short, this is a moderated subreddit, and responses which do not meet our quality guidelines will be removed. Remember, peer reviewed sources are always appreciated, and anecdotes are absolutely not appropriate. In general if your answer begins with 'I think', or 'I've heard', then it's not suitable for . If you would like to become a member of the AskScience panel, . Past AskAnythingWednesday posts . Ask away! | [
"Anything is \"testable\" though not necessarily in a scientifically rigorous fashion.",
"All you need to do is develop a hypothesis about an event and then wait to see if that hypothesis turns out to be right or wrong.",
"However, because this hypothesis was based around a real-world event rather than somethin... | [
"What sorts of things in Political Science are testable? It seems like there isn't much to test."
] | [
"The ",
"Cot-Caught Merger",
" is something that is happening right now in American English. There are also other vowel shifts happening all over the place."
] |
[
"Not purely a science question but: Can you name a female scientist... who is not Marie Curie?"
] | [
false
] | null | [
"Jane Goodall. "
] | [
"lise meitner",
"emmy noether",
"ada lovelace",
"barbara mcclintock",
"rosalind franklin",
"patricia goldman-rakic",
"hanna damasio",
"nancy kanwisher",
"nora volkow",
"judith harris",
"what's my prize?"
] | [
"Watson and Crick probably ripped off Rosalind Franklin, and nobody gave much attention to Rosalind cause she didn't have a Y-Chromosome. That should help you remember her."
] |
[
"What makes rain clouds darker than other clouds?"
] | [
false
] | [deleted] | [
"Exactly. Fun fact: rain clouds aren't as dark as you think they are, they are in fact white but appear black because your eyes can't handle the contrast between the sunlit tops and the shadowed bottoms. You can see this if you look at a cloud through a narrow tube, so that you can only see a small part of it at on... | [
"A rain cloud would be denser (ie hold more water) and have a greater thickness because of the amount of water it holds.",
"Both these factors point to a rain cloud scattering more light than a 'normal' cloud, hence resulting in less light penetrating all the way through it"
] | [
"Similar to the grey cube illusion concept?"
] |
[
"Two Questions. First, Black holes are said to have infinite density. If that's the case, wouldn't their gravitational influence instantaneously suck in the entire universe? Second. If a singularity just 1 dimension, how does a black hole have spin? Don't they need multiple dimensions to rotate?"
] | [
false
] | To further clarify. The first question. If they had infinite density, wouldnt that mean that an object at the event horizon would feel the same powerful pull as an object 50 light years away, or even further? The second question. I think i did a well enough job asking but if you need me to be more clear about the question, i'll gladly update with an edit. | [
"The characterisation of a singularity in any particular way is not very useful for knowing about what's really going on inside a black hole.",
"There are good reasons to expect that there are no singularities and the existence of singularities in General Relativity is generally taken to mean we can't trust it on... | [
"Para199x is right, but let's talk about idealized non-dynamical black holes in General Relativity.",
"1) If you take a finite mass and squish it into a smaller and smaller space, its density goes up. Density isn't fundamental, it's a derived quantity equal to mass/volume. Singularities have no volume, they're po... | [
"Sure. A stationary black hole is a particular type of solution to the ",
"Einstein Equations",
". In general the Einstein equations are stupidly difficult to solve, so to get a solution we can actually write down requires assuming some stuff.",
"The \"stationary\" part has some mathematical definition, the c... |
[
"How does the blood test for food allergies work?"
] | [
false
] | [deleted] | [
"Tests have also expanded to now include IgA and IgM tests and MRT tests. ",
"In the case of these tests, the patient's blood is drawn and then put under microscope to observe if there is an immune response when exposed to a particular stimulus like say pollen. Antibodies and antihistamines are positive confirmat... | [
"Tests have also expanded to now include IgA and IgM tests and MRT tests. ",
"In the case of these tests, the patient's blood is drawn and then put under microscope to observe if there is an immune response when exposed to a particular stimulus like say pollen. Antibodies and antihistamines are positive confirmat... | [
"Nowadays you can test for allergies fairly easily with imunohistochmistry assay's. You create wells coated with the antigen you're testing for, run over your sample, and then run over something that will attach to the antibodies and show this through, for example, a color change. Thsee assays are used to quickly ... |
[
"Why is there discrete states of matter, as opposed to a continuous “spectrum” of matter?"
] | [
false
] | Why does matter go through discrete phases of solid → liquid → gas, rather than a continuous change going through a “buttery” or “syrup”-esque phase? | [
"At the atomic level, the temperature of a substance is a measure of how energetic it's particles are. The higher the temperature, the higher the average kinetic energy of the atoms or molecules that make up that substance. For most substances, these particles attract one another with a strength governed by the var... | [
"Although this is a nice understandable explanation for non-physicists, it isn't really correct. The phases of matter are a thermodynamic, statistical effect. The energy is not distributed evenly across all bonds due to (classical) probabilistic fluctuations, and so if this were the explanation, then we would expec... | [
"Are you sure that it doesn't? Sure, the four phases of matter that you learned in high school are a useful tool, but reality gets pretty complicated when we start carefully examining the boundary between solid and liquid. Highly viscous liquids can be indistinguishable from solids. Particulate solids behave like l... |
[
"What technological advances need to happen before Satellite WiFi, accessible from an normal laptop, is possible?"
] | [
false
] | EDIT: ANY normal laptop. | [
"Iridium has ",
"Satellite Internet from a Laptop",
". I don't know much about it, though I would expect it to be expensive. And it looks like you need an Iridium phone with it.",
"Keep in mind that even current \"Satellite Internet\" isn't as good as it sounds, because of the latency of satellites. The speed... | [
"You would need to build in a ",
"satellite phone",
", something like Iridium."
] | [
"Can you clarify what you mean by 'Satellite Wi-Fi'? I will assume that you mean a laptop capable of accessing the internet anywhere in the world using a dedicated piece of internal hardware that exchanges data with satellites in space. ",
"Issues #1 - Antenna\nWhile you need a big satellite dish to receive a TV ... |
[
"Why does boredom feel the same as being tired?"
] | [
false
] | null | [
"I've been in lectures where I was so bored I could barely keep my eyes open, yet the moment it ends and I step out I'm wide awake"
] | [
"I've been in lectures where I was so bored I could barely keep my eyes open, yet the moment it ends and I step out I'm wide awake"
] | [
"I think it may have something to do with under stimulation of the brain. Perhaps your brain behaves as your computer does if left unactive for a certain period of time; in order to save energy, it 'wants' to go to sleepmode"
] |
[
"If a star cannot fuse iron atoms, what would happen if an large iron body collided with the star? Would it spell the end of the star?"
] | [
false
] | As far as I know, when a star begins creating iron, it basically is in the last stages before death since it cannot fuse iron. Would introducing iron in it cause this process to start prematurely? | [
"It isn't that stars cannot fuse iron - they can, and sometimes do. It's that iron cannot be used as an energy source for the star, because fusing elements lighter than iron releases energy, but fusing iron and heavier requires energy input.",
"You can see in ",
"this plot",
" that iron sits at the highest p... | [
"Also, a star just having iron sitting around isn't a problem. Stars are born with wide variations in their percentage of iron composition. Introducing extra iron wouldn't really matter as long as there's still plenty of H/He or other lighter elements in the core to fuse.",
"You only run into a problem for the st... | [
"Yes.... if you can find a chunk of pure iron large enough. Which would have to be like 10% the mass of the star or so (which is typically what percentage of the star is actively fusing).",
"People have actually thought",
" about what would happen if you had a neutron star merge with a normal star and displace ... |
[
"Question about neanderthals."
] | [
false
] | Given the anthropological differences in the human phenotype, (i.e. shaq vs danny devito) Is it at all possible that neanderthals are a just as "human" as the homo sapien? By which I mean that the differences n body structure would be negligible enough to allow them to live as a human today with little to no issues? | [
"Shaq and Danny DeVito both have the same human DNA sequences and those physical differences you see are really in gene expression. Between a human and a neanderthal the DNA sequences are actually different. A neanderthal that looked physically the same as you would still be more different than Shaq to Danny DeVito... | [
"http://www.newscientist.com/article/dn18869-neanderthal-genome-reveals-interbreeding-with-humans.html",
"Sub-saharan african populations show little or no trace of it. The rest of humanity have it. "
] | [
"Thank you for the informative reply"
] |
[
"My dad used to tell me that i couldn’t buy men’s products, even though they were much cheaper than woman’s products, due to the fact that the chemicals in things like body wash and deodorant reacted differently to afab and amab bodies. Is this true?"
] | [
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",
"A good home for this que... | [
"Hey, we can’t speak to the health or safety of specific products, but I wanted to mention the ",
"pink tax",
". I would definitely encourage you to investigate the ingredients in different products and compare the differences. "
] | [
"That’s not what I’m asking though. The pink tax is something I’m familiar with, in all its shiftiness, but my dads argument was that the chemicals in the different deodorants are inherently different because they were made for different kinds of bodies and they wouldn’t work they way they were supposed to if I did... |
[
"What causes gas flow exiting from a tube to become sonic upon exit into a large vacuum cavity?"
] | [
false
] | I was reading a where the authors assert that any flow (including subsonic flow) from a tube even of constant cross-section will become sonic upon being released into a large vacuum cavity: The exit flow cannot be subsonic given that it must diverge upon exit, and the pressure increase produced by this divergence would make it impossible for the jet to adjust itself to the zero pressure vacuum region. But why is this necessarily the case? If there are gas particles simply moving at some (subsonic) velocity in the tube, wouldn't they simply continue drifting at their instantaneous velocity as they exit the tube and enter the vacuum? What causes them to speed up to the sound speed and/or for the sound speed to decrease? Any explanations on why/how the flow becomes sonic would be appreciated since I seem to not quite understand the authors' arguments nor the physical mechanism(s) at play at the interface with the vacuum. I was under the impression that the gas will stream out at some angle based upon the collisions of the gas particles with the tube and other gas particles. Perhaps the gas density will decrease as it enters the vacuum and expands in the cavity causing the collision frequency to decrease. This would render a kinetic treatment more applicable, but I wasn't suspecting any sonic flow. It appears I am missing a fundamental insight here and clarity (through physical equations and/or intuitive explanations) would be appreciated. | [
"Any flow exiting a tube into a plenum will be supersonic of the pressure ratio is high enough to be ",
"choked",
", about 1.8 for air. This is independent of flow velocity when exiting into a plenum and happens all the time in everyday life with subsonic flows.",
"To answer your broad question, this phenome... | [
"That's a good question, not any \"easy ways\" that I'm aware of. Certainly ",
"shadowgraph",
" or ",
"Schlieren",
" are classic ways to verify or measure the a shockwave.",
"Though to be fair, that's where I probably made a mistake is saying supersonic vs sonic. Most of the everyday situations would end... | [
"This is not choked flow, i.e. the cross-section of the tube is constant",
"It's constant until the plenum, then it's a diverging nozzle, where the flow will choke. It will effectively act as a converging-diverging nozzle, since there will be a discharge coefficient at the exit effectively making the tube smalle... |
[
"Iron and cobalt have similar thermal conductivities (actually, cobalt's is higher) but cobalt takes longer to go from \"red hot\" to not glowing. Can anyone tell me why?"
] | [
false
] | I had both metals in the liquid state, and then they were rested on a chilled copper block. The cobalt took quite a few seconds to stop glowing, but when I melted and solidified the iron, it quickly returned to room temperature. I figure if it's strictly dependent on thermal conductivities, then iron should have cooled faster. If not, there was something else at play (maybe the iron was in better contact with the copper, or the cobalt wasn't fully melted onto the copper and therefore didn't create a good interface). That's pretty much all the information I have. Both metals were >99.5% pure, both were melted to a flowing liquid state with an arc melter on identical, chilled copper blocks. They were both liquidy enough to easily fill in the thin groove of the copper plate. It always seems the cobalt compounds take much longer to cool, but today I did it with just both pure iron and pure cobalt and cobalt still took much longer. edit: before anyone answers, maybe it has something to do with the crystal structure? Cobalt's thermal conductivity has to be different along the c-axis than the basal plane I'd assume, whereas iron's cubic system is more uniform. | [
"Actually, I'd think it'd be the different heat capacities. "
] | [
"With the difference in density around 15%, that might be it. Unfortunately I never timed it, but it seems to be a much larger difference than that. Maybe I'll time it tomorrow."
] | [
"edit: before anyone answers, maybe it has something to do with the crystal structure? Cobalt's thermal conductivity has to be different along the c-axis than the basal plane I'd assume, whereas iron's cubic system is more uniform.",
"The thermal conductivity of any polycrystalline material is isotropic (assuming... |
[
"What would be the gravitational effects of matter beyond the observable universe?"
] | [
false
] | My question assumes two things, first that there is matter beyond the edge of the observable universe, and second that gravity moves at the speed of light. If these are true, it would seem that for something halfway between Earth and the edge of the observable universe, we on Earth would not be able to see everything which is affecting it. Furthermore, it would be acted upon by gravitational forces which Earth is not. My question then is this, would this explain expansion? Would these forces be negligible? Do cosmologists study such things? | [
"I realize that. I'm sorry, but that didn't address my question. Presumably something which is not from our frame of reference, but billions of light-years away, would have a separate observable universe, one which could detect things which we cannot, and be affected by such."
] | [
"I realize that. I'm sorry, but that didn't address my question. Presumably something which is not from our frame of reference, but billions of light-years away, would have a separate observable universe, one which could detect things which we cannot, and be affected by such."
] | [
"Nothing, the observable universe is the bounds of all possible interactions with us, as the furtherst photons from the shortly after the beginning of time would have to cross the radius of the observable universe to get to us. You know what else would have to cross that, the gravitation / gravitational waves. They... |
[
"Could I request a professionally educated list of notable good/bad scientific journals, online news sources, etc?"
] | [
false
] | null | [
"Might want to try ",
"/r/askacademia"
] | [
"I agree with iorg. Your question is better suited for ",
"/r/askacademia",
"."
] | [
"Fair enough, thanks. :)"
] |
[
"AskScience AMA Series: I am byronmiller and I study the chemistry of protocells. Ask Me Anything!"
] | [
false
] | I am a chemist researching questions related to the origins of life. In particular, I'm interested in studying autocatalytic reactions, meaning molecules capable of replicating themselves, and minimal cells or protocells. I'm still early in my career and learn more every day about this huge, interdisciplinary topic. A current project I'm working on involves applying 'systems chemistry' approaches to autocatalytic reactions to see what we can learn about them with new techniques. I'll definitely be on from 9-11pm GMT (5-7 pm EDT) but might also check in at other times a bit earlier. | [
"I'm not too familiar with this field, but in a lot of the systems that I have heard about, the self-replicating structures or sequences that form are the most thermodynamically favorable ones. Obviously in a modern cell, the proteins that are expressed are not the most stable ones but the ones that are the most u... | [
"What are the current theories regarding the precursors to highly complex biomolecules such as RNA/DNA, proteins etc? "
] | [
"What is the coolest thing you've seen a protocell do? ",
"What are their current state, I remember reading about self assembling enclosures some years back, is that still where the field is going? ",
"This may sound dumb, but can I make simple ones at home and put them under the microscope?"
] |
[
"When performing a gravitational slingshot maneuver, does the direction the planet is rotating in relative to a spacecrafts trajectory make a difference?"
] | [
false
] | [Solved] I've probably worded this poorly, and this might seem obvious. I read some interesting comments on a post earlier and when speaking to my friend about it we disagreed on the above statement. While I was able to find lots of information about gravitational slingshots I didn't immediately see any that explicitly mentioned the rotation direction of the planet. I thought that it was the gravitational pull of the planet that accelerated a spacecraft and it wasn't really important what direction it was rotating in. He thought that it was entirely dependant on the rotational direction of the planet and a spacecraft would have to enter its gravity in the same direction. Please can you help me clear this up. Thank you! | [
"You're right, the rotation of the planet about its axis has no impact on a slingshot. What matters is the direction that the planet is orbiting around the sun and where the spacecraft crosses through its sphere of influence."
] | [
"It only depends on the orbital motion, not on the rotation. For all planets apart from Uranus the two happen to be roughly aligned (although Venus rotates in the \"wrong\" direction).",
"Technically there is an effect from ",
"frame-dragging",
" but it is way too small to matter."
] | [
"Normally no, however if you try to make a slingshot off an object with very uneven gravity, then it might make a difference. Imagine a planet where half of it is made of something very heavy, and the other half something very light, in such a way that you experience stronger pull when you're facing the \"heavy\" s... |
[
"If 1/3 in decimal form is .333 repeating, and 2/3 .666 repeating, why isn't 3/3 .999 repeating?"
] | [
false
] | null | [
"It is. 0.999... = 1 = 3/3."
] | [
"But it isn't whole.."
] | [
"https://en.wikipedia.org/wiki/0.999",
"..."
] |
[
"Is cancer immortal?"
] | [
false
] | I just read up on cellular senescence and from what I can tell, it would seem that cancer is immortal. I know that a normal human cell-line can only be passaged so long before it loses vitality due to senescence. Would it be possible to culture a tumor cell-line indefinitely? | [
"Some are. The HeLa cell line is perhaps the best example. ",
"link",
". It still needs nutrients to grow, but from a purely senescence perspective, they are immortal."
] | [
"hallmarks of a transformed or immortalized (cancer) ",
"1- Growth factor independency\n2- No response to growth inhibitors\n3- Evasion of apoptosis\n4- Can promote angiogenesis\n5- Unlimited proliferation\n6- Invasive",
"basically there is a mutation that allows them to simultaneously produce their own growth ... | [
"Yes, this is very useful in making monoclonal antibodies. By fusing a b-cell with a cancer cell, immortalized clones are produced which all make identical antibodies."
] |
[
"Are there diseases that actually directly cause people to gain weight?"
] | [
false
] | Ones that maybe prevent the body from processing fat? | [
"One that comes to my mind first is ",
"Cushing's Syndrome",
", which is caused by exposure of the body to high levels of the hormone cortisol, the hormone released by the adrenal glands in cases of long-term stress.",
"High levels can be due to high doses of cortisol as a drug (it is a steroid, so can be use... | [
"That does not sound pleasant. Thank you for the info! "
] | [
"Heart failure can lead to decreased blood flow to kidney, leading to decreased production of urine, leading to a buildup of fluid in the body. This can cause someone to gain 3+ pounds in a day, and much more over the course of days to weeks."
] |
[
"Regarding solar power electrical grid storage issues. Why are gravity batteries (pumping water uphill during peak electrical accumulation and running it downhill at night i.e. a dam) not an option?"
] | [
false
] | null | [
"For that you need mountains, with two lakes above each other, and a river to replenish the evaporated water.",
"\nMost, if not all suitable sites are already used for that. ",
"1 kW",
" "
] | [
"Pump storage does not necessarily need mountains. See Ludington, Michigan for an example. The idea of pump storage is not efficient storage, but rather generating at peak power rate times. These projects make billions of dollars by playing the energy market. Construction costs are not a deterrent, but rather e... | [
"does not necessarily need mountains. ",
"Two large storage areas with sufficient elevation difference would indeed be a better description. ",
"In flat-as-a-pancake the Netherlands they dreamt up ",
"plan Lievense",
", a hollow island in the North Sea (considered too expensive). "
] |
[
"What is the basis for planets that are \"hospitable for life\"?"
] | [
false
] | Does that mean something that is Earth-like? Is any form of water enough? Does it have to do with oxygen or temperatures, or I guess probably a combination of these things? If so, I guess it "makes sense" that this is what we're looking for, but isn't there a chance that we could miss out on life in other conditions because of our bias? | [
"Basically all we know about extrasolar planets is a) what their orbits are and b) what their mass is. So they tend to say planets are habitable when they are about earth-sized (up to about twice as big) and about the same orbit (so liquid water can be formed). We aren't missing out on any possible life at all ... | [
"We can't analyze atmospheres now?"
] | [
"Not of extrasolar planets, except in a few exceptional cases. Maybe when James Webb comes online..."
] |
[
"Is drinking deuterium depleted water good or bad to your health? Is there any scientific evidence?"
] | [
false
] | There are a couple of papers out there, such as: Biological significance of naturally occurring deuterium: the antitumor effect of deuterium depletion [pdf] | [
"http://en.wikipedia.org/wiki/Heavy_water#Toxicity_in_humans"
] | [
"Note the question is about deuterium ",
" water",
"http://en.wikipedia.org/wiki/Deuterium-depleted_water"
] | [
"How depleted? HDO already only constitutes about 1 out of every 3,200 molecules of normal water, and D2O only about 1 in 41,000,000."
] |
[
"An Apophis impact event: Why is predicting whether or not this (or any observed asteroid) will hit the Earth so difficult?"
] | [
false
] | The orbits of the planets are well known, and the observations of Apophis appear to indicate that it "might" hit us (or more likely Venus).. but there is a large variation in the probabilities. Why are we still having a difficult time predicting something like an impact event for an observed asteroid? Is there a lot more noise and are there more orbital perturbations than are commonly believed? | [
"I guess the answer is \"Pretty Accurate\" given the power we have computationally at our disposal and the importance of the answer to the question...",
"I can understand the weather being difficult to predict, but I, at least, think of the solar system as somewhat uncluttered compared to particles of air and wat... | [
"I guess the answer is \"Pretty Accurate\" given the power we have computationally at our disposal and the importance of the answer to the question...",
"I can understand the weather being difficult to predict, but I, at least, think of the solar system as somewhat uncluttered compared to particles of air and wat... | [
"Awesome, this is what I was looking for. Thanks!"
] |
[
"Why are substance such as gasoline, liquor, and methane flammable?"
] | [
false
] | I don't really understand how certain substances such as gasoline can be highly flammable. Could you explain to me how these substance can be flammable? What happens at the molecular level to make it flammable? | [
"Flammability means that the atom when combined with Oxygen has less potential energy and therefore emits kinetic energy in the form of a flame.",
"When Hydrocarbons like Gasoline, liquor, and methane combine with oxygen, oxygen has very high electronegativity, or want of an electron (It has the 2nd highest elect... | [
"Interestingly, some fuels are not flammable, but are combustible (e.g., kerosene, cooking oil, waxes, etc.) - they must be vaporized first before being able to efficiently combine with atmospheric oxygen. Throw a match in kerosene and it will go out. ",
"What this implies is that certain \"lighter\" fuels have ... | [
"Thank you for the response, I understand it better now"
] |
[
"I was always told that if you did LSD even once, traces of it would stay in your body forever. Is this even remotely true?"
] | [
false
] | [deleted] | [
"No, LSD has a half-life of between 3 and 5 hours. Within a day or two you would have essentially no LSD left in your body.",
"Are there ANY drugs that stay in your system forever?",
"There are things like Dioxins that will stay in your body for decades and heavy metals can become incorporated into your bones.... | [
"It is true that LSD itself will leave the body quickly, and even the metabolites of sd will leave the body within 24 hours. There is still more debate about the longterm effects of the drug itself. Now there are significant reports of the phenomenon of \"flashbacks\" from LSD use, which is normally what is referre... | [
"It is true that LSD itself will leave the body quickly, and even the metabolites of sd will leave the body within 24 hours. There is still more debate about the longterm effects of the drug itself. Now there are significant reports of the phenomenon of \"flashbacks\" from LSD use, which is normally what is referre... |
[
"How does an irregular sleep schedule affect you?"
] | [
false
] | [deleted] | [
"There is actually a disorder to describe this: ",
"Shift-Work Disorder",
"The wiki describes it fairly well."
] | [
"Great link, thanks for the info!"
] | [
"Also, long term puts her at higher risk for metabolic disorder/diabetes."
] |
[
"Do we see with our eyes or with our brain?"
] | [
false
] | [deleted] | [
"I'll throw out two interesting examples: ",
"When blind people are given ",
"alternate means to remotely sense their environments, such as audio headphones that play certain tones when objects are in front of them",
", the part of the brain that \"lights up\" in response to the stimulus is the visual process... | [
"It depends what you mean by using the word 'see'.",
"Your eyes (skin, inner ear and other sensory surfaces) are 'just' receptors surfaces which act to map a sensory stimulus onto the body somehow. In vision, this is with photoreceptors which basically map incoming light into cells which then transfer this to ele... | [
"to quote the ",
"Gorillaz",
", ",
"\"You don't see with your eye, you perceive with your mind.\"",
"Visual cognition researcher here.",
"Seeing (or more adequately stated, \"perception\") is an ",
" process, whereby you take external stimuli from the world and modulate and interpret them based on numer... |
[
"Does water in the atmosphere automatically conclude a strong magnetosphere when observing exo-planets?"
] | [
false
] | null | [
"Hi haydaldinho 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 of the fol... | [
"‘Astronomy’"
] | [
"Astronomy"
] |
[
"Was there a flight test of the Mars Science Labratory's Sky Crane descent system, and if not, why?"
] | [
false
] | In the waning hours before the Curiosity touches down [or not], I've spent my time looking up all the materials for the flight tests I can, and in particular the flight test of the entire sky crane system. All I can find is of the system. The utter lack of material covering a test of the sky crane stage leads me to suspect that no such test took place, either because the rockets are powered for mars gravity or because other tests were considered satisfactory substitutes. If it did not take place, it seems to me like a major step was skipped in the prototyping process. | [
"There's no practical way of simulating Mars' lighter gravity and less dense atmosphere here that they could use to test it."
] | [
"The less dense atmosphere can be simulated in some of NASAs facilities.",
"That's absolutely incorrect. There's no practical way of simulating the conditions necessary for an all-up test of the skycrane system under rocket power. Can you point me to a 500m (or even 100m) tall building they could draw down to a n... | [
"I watched a British science documentary 'Horizon, Mission to Mars' which aired last week. They filmed at JPL for the past year, there was footage of tests of the sky crane being tested in an aircraft hanger or similar building. "
] |
[
"Is there such a thing as \"good calorie\" vs \"bad calorie\"?"
] | [
false
] | null | [
"I believe one significant difference is the time profile of the metabolic energy that these different nutrients make available. Pure sugar causes a short-lived and extreme spike in blood glucose, which will send the blood insulin level soaring soon after it. Simple carbs have a slightly smoother time curve and com... | [
"There are calories which provide more nutrition and those that are \"empty.\" For example a calorie of refined sugar would be less nutritious than a calorie of avocado. You also have \"good fats\" and bad fats like triglycerides. A calorie of an omega 3 fatty acid is better than one of triglycerides. Finally, c... | [
"But what do you mean by \"more nutritious\"? It seems a bit tautological to me: good calories are nutritious, bad calories aren't. What makes something \"nutritious\"?"
] |
[
"What is CECO?"
] | [
false
] | null | [
"That makes sense, thanks!"
] | [
"Are you sure you are not talking about SECO (Second -stage- Engine Cut Off)?"
] | [
"Maybe it was just a typo? The sentence says: “The LIFTOFF light is turned off at S-IC CECO.”"
] |
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