title list | over_18 list | post_content stringlengths 0 9.37k ⌀ | C1 list | C2 list | C3 list |
|---|---|---|---|---|---|
[
"How is a DNA sample computerized?"
] | [
false
] | In other words, what is the process to take a biological sample and convert it to code that can then be stored and analyzed by a computer? For example, what would I have to do a sample of my own cheek cells in order to be able to upload my own DNA profile to GEDmatch? | [
"How much detail of the process do you want? You can write a whole book about it.",
"First you need to extract your DNA from cells and purify the DNA. Then sequence it.",
"This video is a good start about sequencing. ",
"https://youtu.be/ONGdehkB8jU",
"Or have a look at Sanger sequencing.",
"These colorfu... | [
"Its important to distinguish between DNA sequencing, which is regularly performed in scientific research, and Genotyping, which is provided my most of the genetic testing organizations. DNA sequencing reads the actual sequence of A, T, C, and Gs in a molecule of DNA. Once this sequence is determined (using a chemi... | [
"Bioinformatician reporting in.",
"The different sequencer manufacturers usually have some sort of immediate \"raw\" data format their machine outputs - for example, the light intensity data from an Illumina machine. These are converted (by manufucterer-specific software) to a more usable format, usually ",
"fa... |
[
"Could Voyager us the transit method to detect “planet 9”?"
] | [
false
] | null | [
"The tricky thing is that the planet's orbit needs to be exactly lined up with the probe, otherwise the planet won't transit from the probe's perspective. Also, transit methods aren't great for distant objects, because the orbital period is so long - over centuries - so the odds you'll catch one when you're looking... | [
"An object 100 AU away from the Sun has a chance of about pi*(radius of Sun)",
"/(4 pi*(100 AU)",
") or ~1 in 2 billion to be in front of the Sun at any point in time, with the optimistic assumption that the spacecraft is much farther away. Watching for 10 years increases that chance to something like 1 in a mi... | [
"No, I used the full solid angle. If you are in the same plane the chance is much higher."
] |
[
"If data analysis from mapping dark matter conflicts with general relativity, what does that mean for our understanding of the universe?"
] | [
false
] | I was reading a BBC article on a new effort to map dark matter, and it stated that with this data is the possibility of disproving general relativity. What would that mean for science? Would things that seem impossible (time travel, for example) suddenly become a possibility? Not sure if I am taking the statement too l... | [
"Science = we've got a Lot to learn yet... Nothing is taken as the end-all of knowledge. All theories are meant to be 'obsolete' when further information becomes available. Newton used the mathematics available to him, Einstein had the use of more advanced data, and there is still more available today than he had a... | [
"Interesting. So it's more accurate to say that these theories will continually be expanded upon, rather than replaced?"
] | [
"People have said the article is sensationalist, I disagree but I think people have the wrong end of the stick here. People are really trying to test GR on cosmological scales as we speak. It's not that GR would be flat out wrong or obsolete but that it didn't describe gravity on cosmological scales, but is still c... |
[
"Are there any asteroid \"blind spots\" in our survey areas?"
] | [
false
] | I read in an article some time ago about the possibility of an asteroid surprising us from a blind spot behind the sun. Is this still possible or was it a myth in the first place? Thanks! | [
"Any impact would be a surprise. Hiding behind the sun isn't necessary, we didn't see most asteroids that were in \"plain sight\" until we really started looking. Here's a YouTube video showing the rate at which we have discovered asteroids. You'll notice that most discoveries are facing away from the sun, since th... | [
"At any point there could be an asteroid directly opposite the sun from us, and so we wouldn't see it from Earth. In fact many Earth-bound telescopes don't look anywhere near the sun, only making observations in the night sky.",
"However, that asteroid would be seen at other times in the year when it, and Earth, ... | [
"Thank you. So the odds of a \"surprise\" impact from around the sun are low?"
] |
[
"AMA; What would you like to ask entomologists"
] | [
false
] | I'm at the Entomological Society of America meeting this week. I've got the opportunity to talk to a bunch of different people this week and actually film them answering questions. So, what would you love to hear an entomologist answer? I'll take your questions and film actual entomologist answering them. Edit: And if ... | [
"Has there been any successful eradication of invasive insects? I live on Guam and we are attempting to control the ",
"coconut rhinoceros beetle",
". They are incredibly damaging to many species of palm trees. All attempts have failed. They were first noticed 5 years ago in the hotel district, but have now spr... | [
"Are the bees totally fucked? Are we?"
] | [
"Asked this ",
"before",
" on AskScience, this might be a good question - has any insect displayed evidence of self-awareness or the ability to learn? Or are insects all on \"autopilot\" (all actions just predictable and consistent reactions to stimuli)?"
] |
[
"Am I getting this right?"
] | [
false
] | [deleted] | [
"So I think one of the first good things to realize is that space is not a thing. It's a measurement. Point A is x meters away from point B at angle theta with respect to the line between B and C. The measurements change over time, they grow between objects that don't have much gravitational attraction to each othe... | [
"Why things appear larger: Draw a line across a page. from the middle of the line extend another line perpendicular to it. Then draw a point on that second line ",
" to the first line, and a point on the second line ",
" from the first line. Then construct triangles with that first line and those points. The ne... | [
"Why things appear larger: Draw a line across a page. from the middle of the line extend another line perpendicular to it. Then draw a point on that second line ",
" to the first line, and a point on the second line ",
" from the first line. Then construct triangles with that first line and those points. The ne... |
[
"Defining the metric tensor for a given manifold."
] | [
false
] | Hi everyone. I just wanted to know if one can define or construct a metric tensor for any manifold (given the necessary conditions, such as the fact that the metric is differentiable), and if so, then how? For example, I have only seen the metric tensor of a flat euclidean space, as well as that of a 2-sphere, and alth... | [
"Yes, any manifold of dimension m can by embedded into R",
" isometrically. Then you can simply use the induced metric. But n is in general much larger than m and the embedding is not easy to find, so this is not very practical.",
"If you are asking on how to find the induced metric for a submanifold of R",
"... | [
"You can either take the metric tensor as a given (which is the intrinsic/Riemannian point of view), or you can compute it from the embedding. In the former situation it doesn't make much sense to \"compute\" the metric, as it is simply a given. The metric is in this sense what defines the shape. The latter one (... | [
"The idea of embedding a manifold into R",
" is simply identifying the manifold as a subset of R",
" For example, I can think of a sphere as a 2-dimensional manifold and it embeds into R",
" in the obvious way. But say a Klein bottle (which is also a 2-dimensional manifold) can't be embedded into R",
" but ... |
[
"Switched to contact lenses. Now everything's huge. Which reality is correct?"
] | [
false
] | I've been wearing glasses for 10 or more years now. Have a strong prescription. Around +12 in one eye and +14 in the other. Last week I switched to contact lenses. Wow, what a difference. Everything near me appears SO much physically larger, almost like I shrunk several inches. Relatedly, any objects that are semi-clos... | [
"Do you mean like this?",
"\nI don't know how much you can actually see outside of your glasses, but I guess your glass didn't just make everything you see through it sharper, but bend what you can actually see. So if you see a straight line (for example the side of a tall building) going through your complete vi... | [
"The glasses were distorting, and the contacts distort far less. You can see this by looking in a mirror while wearing your glasses. I have a strong prescription as well. You can typically see that your head pinches in where the glasses are, such that you can see the wall to either side of your head through the l... | [
"Strong glasses create parallax distortion because the light is refracted twice, as it enters the lens, and as it leaves the lens. Contract lenses sit right on your eye, and are much thinner, so there is less distortion. ",
"You can really notice the effect by looking through a doorway, at some line parallel to... |
[
"What exactly causes our ears to \"ring\"?"
] | [
false
] | I'm not talking about constant ringing, just the occasional ringing we all experience. Also, I understand that loud noises cause it, but that's not what i'm asking. I mean what exactly is happening in our ear that makes it sound like a high pitched note? | [
"Sorry but that's not an accurate response about tinnitus at a number of levels. First of all, tinnitus' proximate cause is usually damage to hair cells in a specific place on the cochlea but the actual ringing is NOT the sound of your hair cells dying at all. When the inner sensory hair cells in a region are dam... | [
"Sorry but that's not an accurate response about tinnitus at a number of levels. First of all, tinnitus' proximate cause is usually damage to hair cells in a specific place on the cochlea but the actual ringing is NOT the sound of your hair cells dying at all. When the inner sensory hair cells in a region are dam... | [
"Do the hair cells grow back after they die? Or rather do new ones grow in their Place?"
] |
[
"Has the nuclear age prevented future carbon dating?"
] | [
false
] | Using C to figure out the age of organic stuff makes assumptions about it being generated in the atmosphere at a relatively stable rate and without huge geographical variations. Did nuclear weapon tests and releases from power plants both during normal operation and events like Chernobyl graphite burning up create enou... | [
"Limnologist here (lake study). I don't know about Carbon dating, but for more recent work (10 - 500 years) we use Lead-210 dating. Exact same principles apply, one form of lead is produced at a steady rate, and decays with a known half life. By looking at the amount of these in lake sediments we can tell when they... | [
"\"Nuclear tests, nuclear reactors and the use of nuclear weapons have also changed the composition of radioisotopes in the air over the last few decades. This human nuclear activity will make precise dating of fossils from our lifetime very difficult due to contamination of the normal radioisotope composition of t... | [
"As someone whose group does nuclear forensics, the short answer is no. The long answer is kinda.",
"Fission directly creates \"fission products\" whose range of A(atomic weight) is from 70 to 167 (this includes U-233, U-235, and Pu-239). C-14 is also made indirectly since fission also releases neutrons, N-14 (wh... |
[
"Is P=NP itself a P or NP problem?"
] | [
false
] | Some points I'd like to consider. Does the algorithm to solve the problem "Does P=NP" run in P or NP time? Does the solution to this problem give any insight as to if P=NP? | [
"The question \"does P = NP?\" is a statement about decision problems, but isn't a decision problem itself (in the sense in which computer scientists use the term). Here's what that means:",
"Problems like 2-SAT (which is in P) or 3-SAT (which is NP-complete) can be viewed as questions about ",
". In computer s... | [
"I don't mean to detract from your correct reply by nitpicking, but you should be careful with the use of the word Turing-equivalent. Turing equivalence refers to computability rather than complexity.",
"A TM with an SAT oracle is trivially Turing-equivalent to non-augmented TMs (since the oracle can be simulated... | [
"Thanks for the correction, that was sloppy of me. I think I was vaguely remembering the \"extended Church-Turing thesis\" which postulates that all reasonable, sufficiently powerful computational devices are polynomial-time reducible to each other."
] |
[
"WHY is the magnetic force perpendicular to the velocity and magnetic field of a particle?"
] | [
false
] | Background: college level calculus-based physics. I understand that Fb = qV x B I understand how this cross product works, and that it is dependent on the angle θ between V and B. I understand that the right hand rule is a useful tool for demonstrating the direction of the three components, and that in practice: * We p... | [
"The best answer I can give that would have us look at relativity. When a charge is stationary, everyone around it will see an electric field. But if we're moving past that charge, we'll see a magnetic field. So if some other particle is moving in the field of that charge, it's feeling a magnetic force, while the s... | [
"In short; particles that take nice, straight line paths and accelerate linearly in ",
" fail to do so if looked upon by a fast moving observer - the particle curves weirdly. To the observer, he concludes there is another field at work. He works out its properties and calls it B."
] | [
"You can get magnetic monopoles from topologicaldefects. There is no honest magnetic charge density, but rather a topological field configuration that acts like a magnetic monopole. this can be accomplished in symmetry breaking scenarios."
] |
[
"Why does it take a year or more to develop vaccines?"
] | [
false
] | I've read that vaccines work by introducing a mild version of the virus to the body so that it can develop an immune response. Also have heard that the entire genome sequence of COVID-19 and other viruses are uploaded online. So what's the rate determining step here? Also related, of what use is making public the genom... | [
"So what's the rate determining step here?",
"First you need to actually create the vaccine, and at that point biology (how long cells take to grow etc) is rate-limiting. Then once you have it, you need to test it via clinical trials to show that it's safe (Phase 1, healthy patients), and effective (Phase 2&3, ef... | [
"I had only considered the research and production phases of vaccines development and wondered why that took so long (given the global effort to fight this emergency). But from your answer I see now that the testing phase completely slipped my mind. I guess even a fast-tracked version of clinical trials would take ... | [
"why that took so long (given the global effort to fight this emergency)",
"Yeah, definitely not limited by scientists sitting around brainstorming, but by hard limits. (All the obvious and semi-obvious ideas were thought of within a day or two of the outbreak). Consider also how a vaccine works as opposed to oth... |
[
"Why do viruses/germs/diseases weaken and kill their hosts? Wouldn't it be more beneficial to strengthen them instead?"
] | [
false
] | Following this line of thought, is there any cases in which these things benefit the host? | [
"There's a lot of viruses, bacteria and fungi that live with us with out killing us. E.g. herpes (except for rare cases, mainly just a nuisance), the bacteria in your colon that actually help in digestion, and my favourite, wood termites don't actually digest wood, bacteria in their stomach does (that's a huge adva... | [
"Viruses and bacteria often weaken and kill their hosts because they're trying to out compete the other viruses and bacteria. For instance, say your bacteria A, and you grow slowly but your host will live for a long time. You're happy, your host is happy and its called a symbiotic relationship. A good example is al... | [
"It's also a matter of the foreign antigens (genetic ID markers on the foreign invader) going at war with your antibodies. Basically your immune system and whatever infected you are constantly trying to kill one another. Some antigens go unnoticed and replicate as \"self-cells\" and don't get destroyed by your imm... |
[
"Why is the Chernobyl New Safe Confinement dome only good for 100 years?"
] | [
false
] | Is it only needed for 100 years, or will something occur to it to make it inoperable? And what is it actually made out of? | [
"100 years is the reference lifespan for the structure. I.e. engineering decisions and safety margins were developed around the expectation that the probability of failure before 100 years should be below some determined amount. In all likelihood, it could exceed 100 years of useful life."
] | [
"Aside from what others have said:",
"We don’t necessarily know how to build a 1,000-year or 10,000-year structure. Some of our modern building materials and techniques simply haven’t been tested that long.",
"Such a structure would be eye-poppingly expensive. In fact, it may even be both more expensive and wor... | [
"The pyramids are ~5000 years old and should stay around for at least tens of thousands of years more.",
"The Pyramids exist in a dry weather climate without much rain or freezing. The long term weather erosion in a Central European climate is much, much worse.",
"Also, the pyramids didn't have to be moved aft... |
[
"Why does smaller diameter of capillary increase rise of water?"
] | [
false
] | null | [
"This is a process called ",
"capillary action",
" - to quote the article: ",
"If the diameter of the tube is sufficiently small, then the combination of surface tension (which is caused by cohesion within the liquid) and adhesive forces between the liquid and container wall act to propel the liquid.",
"The... | [
"A smaller capillary diameter means that more of the water (on a per-volume basis) gets to be next to the glass. This arrangement is energetically favorable because water and hydrophilic glass tend to form bonds that would otherwise be unsatisfied if the water and glass were each next to air. The energy benefit pay... | [
"I wouldn’t find this analogy useful, but everyone relies on different mental models."
] |
[
"Is ketosis the reason bears can hibernate all winter and arise from slumber still buff as fuck?"
] | [
false
] | (x-post from ) | [
"Beta oxidation",
" [break down of stored fat] is probably more the reason the bears become \"buff\" during hibernation. FA catabolism yields a net production water, which is necessary for life and provides the water for the bears to survive the long winters. Same idea for camel humps and how they can also surviv... | [
"If you put humans on a keto diet, and keep them in hospital bed for four months, smart money says that they'll have lost a lot of fat, but they will also have lost a load of muscle. But those bears are fit enough to chase your ass if you wake them up. ",
"There are a number of scientific papers on the subject if... | [
"There was a post in this subreddit recently regarding bears and bee sting resistance where somebody pointed out that bears have more than 20% body fat (if I remember the numbers right) ",
" a winter hibernating. So I wouldn't say that \"buff as fuck\" is an appropriate description.",
"Edit: ",
"here",
" i... |
[
"Is there a neurological/psychological reason explaining why rape often causes more significant and longer lasting emotional harm than other forms of physical violence?"
] | [
false
] | How does adding sex to physical abuse change the effect so drastically? For the purposes of this question, lets assume the rape is an isolated incident. My guess would be that it has to do with our cultural attitudes regarding sex, but are there any more scientific answers to this question? | [
"This is ",
"an interesting recent discussion",
" from ",
"/r/asksocialscience"
] | [
"Thanks for this!"
] | [
"penguineofevil has the best responses that are backed up by science. Mine are pretty decent, too."
] |
[
"Why most people seemingly have such a low tolerance for repetition?"
] | [
false
] | [deleted] | [
"I have no idea, but try to answer ",
"this"
] | [
"I don't find this statement to be true for all activities. Could you be more specific and point to an example?"
] | [
"I have no idea, but try to answer",
" this."
] |
[
"If a Tunguska-like meteoroid impact event happens every few hundred years, then what are some others from our recent recorded history?"
] | [
false
] | Everywhere I look up the Tunguska event of 1908, it seems to suggest that a meteoroid of this size impacts Earth every few hundred years. Some go so far as to put it at around every three hundred years. But I couldn't find references to any other impact event of this scale from the last two millennia. What am I missin... | [
"Let's first examine the expected frequency of such an object entering Earth's atmosphere. The first thing to consider is that the details of the object are not known precisely and there is a range of object details (e.g., diameter, density, impact velocity, angle, etc) that can realistically produce what was obser... | [
"suggested an air burst may have caused the Younger Dryas (e.g., Firestone et al., 2007, Wittke et al., 2013),",
"All I can add is that someone called \"Firestone\" working on meteorite research is some of the best nominative determinism I've ever seen."
] | [
"Thanks. I really appreciate this detailed, informative reply."
] |
[
"Is carbon monoxide toxic to plants like it is to humans?"
] | [
false
] | null | [
"It contributes in its redox (reduction-oxidation) balance if oxygen is not available. It is not toxic, but it can influence photosynthesis. ",
"Sources:\nCarbon monoxide fixation by plants\nR. G. S. Bidwell and Gail P. Bebee\nCanadian Journal of Botany\nVol. 52: Issue. 8: Pages. 1841-1847 (1974)",
"Carbon Mono... | [
"I seriously doubt it. They just want the carbon. If you look at marine plants they take in hco3 co2 and one other molecule I forget off the top of my head- which one of those three is based on pH and availability. You can track it with stable isotopes but it's also why marine plants can have stable isotope sign... | [
"I don't know what it does to plants. In humans, CO binds hemoglobin at a much faster rate than oxygen. It kills humans because it keeps oxygen from getting to the body's cells. Plants don't breathe the same way we do. I imagine that it isn't great for them, but probably isn't quite as immediately toxic. "
] |
[
"How much does pressure expedite melting of snow?"
] | [
false
] | I just parked a car on compacted snow. Will the weight of the car significantly expedite the melting of snow under the tires? The car weighs roughly 4000 pounds, so there will be about 1000 pounds on each tire (P185/65SR15.0BSW AS tires). | [
"Nah, mostly because the snow can squish out to the sides of the tire, so the volume isn't really constant and the temp is probably going to drop at night to help keep things frozen. It may melt ever so slightly then refreeze very quickly into more of an ice form than powderey snow though. However, if you were comp... | [
"That's consistent with past experience, the tires sink a little into the snow but not enough to worry about immobilizing the vehicle. Thanks."
] | [
"If anything, compacting snow will slow its melting. ",
"Like so",
"."
] |
[
"Trying to find books on pre-religion history?"
] | [
false
] | Can anyone recommend anything? I'm particularly interested in history available on times prior to the wide spreading of religion. If any such texts exist. I haven't managed to find any suitable looking books so far. | [
"It would seem religion pre-dates recorded history. ",
"This",
" is pretting interesting, although kind of the opposite of what you're looking for. It's an attempt to recreate the prehistoric religion of the first major civilization by tracing similarities in different cultures mythologies backwards."
] | [
"That's a tall order. Even early modern humans (our earliest homo sapien ancestors who lived alongside Neanderthals) are theorized to have had some animistic beliefs, though there's a lot of debate around that. If you could find a book on prehistoric human social structures, that's probably about as close as you'd ... | [
"There may very well have been one point in human history where religion suddenly caught on wholesale. The problem is that any work you could find on that front would be highly speculative, just because of how far back you'd have to go to find humans who had no concept of religion. ",
"There's also some anthropol... |
[
"If I were to fall into a black hole, from my point of view, would all matter that the black hole had consumed over its lifetime fall in simultaneously?"
] | [
false
] | So, from an outsider's (outside the event horizon) point of view, matter falling into a black hole never crosses the horizon - or, it does, but the timeline of it doing so is infinite, so I'll just say "never" even if that's not technically accurate. I was thinking about where, from the perspective of an insider, cons... | [
"Let's say you and a buddy fall into a black hole. He jumps in first. You wait a minute and then jump in after him.",
"From your point of view, he accelerates away from you and redshifts into blackness. I recommend this site for more details,",
"\n",
"http://casa.colorado.edu/~ajsh/schw.shtml"
] | [
"I'm talking more what happens after this point. I eventually cross the event horizon, and it seems like he will eventually be inside it as well. I'm just not sure when. "
] | [
"You may still see your buddy even if you are both inside the horizon already. It's just ",
" he'll be too hard to see anymore."
] |
[
"Is there a need for a larger particle accelerator?"
] | [
false
] | Do bigger accelerators mean better results? Is there even a plateau for how large one can be and still be an improvement? Is there anything we could even discover with them after the Higgs Boson particle? | [
"wakefield accelerators are an interesting new(ish) direction. The charged particle's acceleration is due to the electric field of a plasma that has been 'structured' using for instance a laser beam, or another particle beam. ",
"The accelerators are considerably smaller than you can achieve with traditional tech... | [
"Do bigger accelerators mean better results?",
"In general, \"bigger accelerators\" means higher intensities and higher energies. These are the two basic things we need to push the limits of our understanding.",
"On the frontier of particle physics, you need higher and higher energies to look for new particles ... | [
"Yes I was being semi-literal with the word \"big\". To reach higher intensities and energies, you typically need a machine which is physically larger."
] |
[
"When drugs are invented by accident (penicillin, sildenafi, benzodiazepines) how are they tested for their effects?"
] | [
false
] | [deleted] | [
"The same way any other drugs are tested for their effects - you isolate the compound, administer some fixed dose, and observe the physiological changes. Like any other novel compound, this starts ",
", then continues on the normal drug development phases.",
"For something like Viagra, where a side-effect disco... | [
"If a molecule exhibits some unique, desired effect and this is discovered completely by accident, there are many examples of researchers testing these on themselves, purposefully or inadvertently. This ranges from simple compounds such as diethyl ether (for use as an anesthetic) to LSD.",
"LSD is a notorious exa... | [
"Is it accurate to say any of these are invented, or are they just discovered?"
] |
[
"Is there any detectable amount of salt (Sodium Chloride) in foggy sea air?"
] | [
false
] | [deleted] | [
"Yes, sea salt aerosols are a common and effective condensation nuclei. Normal wave action produces very small droplets of sea water which evaporate leaving behind salt particles which may be suspended in the air. The salt particles allow water vapor to condense on their surfaces, eventually forming the water dropl... | [
"I think you vastly underestimate the transport distances of tiny particles/drops. For example, ",
"dust from the Sahara makes it to South America",
". Check out the ",
"Wiki fog article",
" also, it notes that salt crystals can provide the nuclei on which fog water droplets form."
] | [
"There is no salt content in early morning fog.",
"I live close to the ocean, and I gotta say that the characteristic tang of salt in the air is one of the simple joys of living on the coast. Have you never been near the ocean?"
] |
[
"Yeah, yeah, yeah, humans received AIDs from monkeys. Do species other than humans have sexually transmitted diseases?"
] | [
false
] | [deleted] | [
"Yes, ",
"koalas for example have a terrible problem with chlamydia",
" which is having severe negative effects on the population in the wild. The disease is transmitted not just in male-to-female sexual activity but indirectly as well (such as from nursing mothers to their children), and some koalas engage in ... | [
"Yes, sexually transmitted diseases affect other species as well e.g. vibriosis in cattle."
] | [
"An example: I originally heard about this in a pet shelter,",
"http://www.veterinarypartner.com/Content.plx?P=A&A=1313"
] |
[
"Is using directions for light polarization just a model?"
] | [
false
] | [deleted] | [
"I think that it is actually parallel to the axis. I think this as polarised sun glasses have a lot of vertical strips therefore are physically blocking all light that it not oscillating vertically. Analogue TV antennae are also physically pointing vertically and horizontally. "
] | [
"Well, that's why polarization filters work. What do you mean by \"just a model?\""
] | [
"Perhaps I worded that too strongly. It's still not spinning in the classical sense."
] |
[
"How will people be able to identify when any of the coronavirus vaccines begin to work?"
] | [
false
] | null | [
"Depends what you mean. \nIf you wanna know if it's worked on:",
"Yourself, you won't know without an antibody test,",
"When the vaccines actually begin to work, that depends on each one, but it's normally between a week and 3 weeks",
"The general public, you'd have to check the data for infections, hospitali... | [
"\"When\" in terms of time after receiving the vaccine?",
"Pfizer/BioNTech have a nice plot showing how people get sick over time. Directly after the first dose both the placebo group and the vaccinated group have cases at the same rate. After around 10 days there is a sharp kink in the vaccinated group, from the... | [
"When you get the second dose, there are “side effects” like low fever, tiredness, etc. Those are NOT you getting sick, but are actually your body’s reaction to fighting the crown proteins of the COVID-19. I’ve heard doctors describe getting the side effects as evidence of the vaccine “taking”, as in having an effe... |
[
"When SETI detects a radio signal and states that it came from the region of a certain star many light-years away, how do they determine that considering that the signal has taken so long to reach Earth?"
] | [
false
] | null | [
"The thing you have to take into consideration is that visible light and radio waves both travel at the speed of light, due to them both being light. When you point a radio telescope at a star, you're receiving signals sent at exactly the same time as the visible image of the star when you point an optical telescop... | [
"It didn't even occur to me that the light and radio waves would reach Earth at the same time. It makes sense now, thank you."
] | [
"Even if there would be a few years of delay: Stars don't move that much within a few years. Our constellations are largely still the same as 2000 years ago, with only small differences. And we know the motion of all these stars."
] |
[
"Why don’t freight container ships and other large ocean vessels use nuclear reactor engines like aircraft carriers?"
] | [
false
] | null | [
"Such questions are better suited for our sister-sub ",
"/r/asksciencediscussion",
". Please post there instead."
] | [
"Why?"
] | [
"Why something is or isn't done or whether something should or should not be done is not a direct science question."
] |
[
"Which material has the highest power to weight ratio when used as a spring?"
] | [
false
] | In the construction of quite large springs (a clockspring) in the order of several KG of weight, what is the most efficient material interms of power stored in the spring to weight of the spring? Is there a list of materials somewhere that has the apprx. amount of Joules one can store in the material when used as a spr... | [
"Making a few assumptions, the maximum energy stored per unit mass is 0.5 * σ",
" / ρE",
"So you want a material which is extremely strong (yield stress σ), but not too dense (ρ) and not too stiff (Young's modulus E). By this metric, fibers such as Kevlar come out way ahead of metals and ceramics."
] | [
"Doesn't a stiffer material just mean you can store more energy in the same volume? Intuitively, a spring that's twice as stiff could store the same amount of energy in half the space (as long as the pressure doesn't exceed the yield strength)."
] | [
"I look forward to the day Nike markets runners with ",
" on the sole..."
] |
[
"Why is our throat dry when we feel thirsty? What is happening biologically?"
] | [
false
] | null | [
"Fuck. My math was way off. ",
"Runners generally take about 180 steps per minute. For some reason I thought that breathing 2:2 would be 90 breaths a minute, whereas it would only be 45. 3:3 would be 30. ",
"Tl;dr: I'm an idiot."
] | [
"Well, a dry throat doesn't necessarily mean you're dehydrated. A dry throat ",
" a symptom of dehydration, but a lot of times dry throats are caused by literally a lack of moisture in your throat and not your body.",
"The best example I can come up with is if you're running. The longer you run, the more you're... | [
"This isn't super relevant, but I think it's a cool statistic that, on average, you actually breath in and 60-90 times every minute."
] |
[
"What sample problems would be near instantaneous to solve in Quantum Computers that a regular computer might need a potentially encumbering amount of time to equally process an answer?"
] | [
false
] | null | [
"You are a bit too confident in our ability to categorize problems. There is no problem known to be in BQP - P. There are just problems that are known to be in BQP and not known to be in P. Whether BQP is a true superset of P is a topic of hot debate.",
"It is also not enough for a problem to just be outside of P... | [
"There is a special class of problems called ",
"bounded-error quantum polynomial time (BQP)",
" problems. These are defined as problems which can be solved in polynomial time by quantum computers with high probability.",
"BQP problems are a ",
" superset of P problems, problems which can be solved in polyn... | [
"That's fair, I adjusted the response."
] |
[
"What are some practical applications for prime numbers (especially the large ones)?"
] | [
false
] | Inspired by the end of this rather awkward and funny interview: | [
"Prime numbers are the basis for RSA code, which is used to encrypt information like credit cards online. I'm not very proficient on the subject though. If we have two huge primes and multiply those numbers, we get a huge number that is not prime. The fact that it factors into two primes is essential to encrypting ... | [
"1.\nStart with two very large random prime numbers, p and q. Typically, a fast probabalistic test like Miller-Rabin is used to find random primes.",
"2.\nLet n = p*q. Multiplying p and q is trivially easy, but the reverse operation (factoring n into p and q) is incredibly difficult. So difficult, in fact, tha... | [
"A lot of people are making this comment, but it's not true at all. The security comes from the fact that it's very hard to factor a product of two large primes, but if I know your key uses a prime that's over 17 million digits long, I'll be able to factor it right away because I'll know that one of the factors is... |
[
"The other day, my math professor was discussing something. I'm wondering if anyone knows the name of what he was discussing."
] | [
false
] | He was talking about some theorem that involves two points on opposite sides of a sphere, such as the earth. It was something along the lines of this: If you have two quantities that can be related as a continuous function on one side of the earth, then there is a spot directly on the opposite side of the earth that ha... | [
"He was talking about (and I'm being completely serious) ",
"the hairy ball theorem",
", or one of the ",
"corrolaries",
" that follows from it."
] | [
"I think the corrolary theorem is the one about which he was talking. Thank you very much for finding it!"
] | [
"Theorem: If f is a continuous function from a circle to the reals, then there are antipodal points where f takes on the same value.",
"Proof: We parametrize f so that f(0) = f(2pi), and in between corresponds to the value of f at that angle.",
"Consider g(t) = f(t) - f(t + pi). This is the difference of the an... |
[
"Why is nitrous oxide so dangerous as a supercritical fluid?"
] | [
false
] | I recently read about an explosion of an hybrid rocket using nitrous oxide [0]. I've been reading about the supercritical state of fluids and it's quite interesting. As you can see in this graph [1], at 310K and from 70 to 90 bar, a small change in pressure means a big change in density. It looks like that kind of thin... | [
"NO2 is always a powerful oxidizer. As a supercritical fluid it just happens to have a large contact area (gasses only randomly interact, a supercritical fluid would almost be a liquid and so in constant contact). The main specific reason NO2 is an oxidizing agent is - well - just do the bloody lewis dot diagram.... | [
"That's... very interesting and informative. Thank you, really, I was starting to think no one would answer :)",
"BTW, if the answer is that NO2 is worse as a supercritical fluid because is like a liquid, does that mean that NO2 as a liquid is equally dangerous (in terms of probability to create an explosion)? Ca... | [
"Thanks for the answers people! I have another question, how are pressure waves related to explosions? it's just because they are the ones that propagate high pressure through a fluid (for example, helping the fluid reach a dangerous point of pressure)?"
] |
[
"Is it possible to magnetize a hollow sphere such that one pole is the surface and the other pole is the interior?"
] | [
false
] | null | [
"Nope, or at least not without the existence of magnetic monopoles. The divergence of the magnetic field must be zero, and the setup you've described is not divergenceless."
] | [
"It's a strict theoretical impossibility, but the question of \"how\" it would go wrong if you attempted to do this is an interesting one, and one I don't know the answer to. It would be fun to try!",
"My guess would be that you'd get very strange behaviors at the boundary where you try to join your sheet into a ... | [
"There are a lot of things I could get away with if I had an infinitely large hollow sphere ;)"
] |
[
"Since the universe is expanding, why doesn't the space in between the atoms and molecules of my body expand as well?"
] | [
false
] | [deleted] | [
"Take all of the mass of the Earth and concentrate it in a symmetric shell. From outside the shell, the gravity you'd feel is the same as you would around the Earth. Inside the shell, however, you feel nothing; the gravity from the shell balances out perfectly. If you put some other object in the center, the only g... | [
"Not true at all. We are completely decoupled from the cosmic expansion. I'll make a top-level post about this."
] | [
"So the big rip scenario is completely debunked now?"
] |
[
"What does it mean for two orbiting bodies to have resonant orbits?"
] | [
false
] | For Example Neptune and Pluto have a 2:3 resonant orbit. | [
"It just means that their orbital periods have a whole-number ratio. 1:2 and 2:3 are common resonances. Resonances occur because they are more stable configurations than non-resonant orbits. 3 of Jupiter's major moons, Io, Europa, and Ganymede, have a 1:2:4 resonance."
] | [
"So for the Pluto Neptune example does that mean for every 3 orbits of Neptune Pluto does two? And if so how does that happen?"
] | [
"So for the Pluto Neptune example does that mean for every 3 orbits of Neptune Pluto does two?",
"That is correct.",
"And if so how does that happen?",
"I'm not sure what you mean. Neptune is closer to the Sun than Pluto is on average, so it travels faster and has less distance to cover in order to complete a... |
[
"Is there a way to slow down the speed of light?"
] | [
false
] | null | [
"We can make it longer for light to go a certain distance, but the light is still actually traveling the same speed between atoms. ",
"See here"
] | [
"While everything is true in what you said, often hypothetical situations are there because the questioner is trying to understand the relationship between things in the real world. Here, they're trying to understand how the speed of light and energy of a photon respond to a gravitational source. You can most defin... | [
"Nothing would happen to the photon. Even if the black hole appeared instantaneously after the photon passed, the propagation of the gravital wave it produces will be moving at the ",
"same speed as the photon itself",
" and can never \"catch up\" to the photon to effect it in any way."
] |
[
"How do we know that Pi goes on forever?"
] | [
false
] | I was wondering about Pi. How do we know that there is no final end to its decimal places? | [
"Well, 1/3=0.3333.... has no end to it's decimal place, so it's not really that special of a property. In fact, almost every single number has a decimal expansion that doesn't terminate, so it's extremely not special!",
"A decimal expansion of a number eventually starts repeating itself after some point exactly w... | [
"Assume that pi=A/B, is rational. For any positive integer N we can then make the polynomial",
"So if N=2, this would be x",
"(A-Bx)",
"/2 = (B",
"x",
"-2ABx",
"+A",
"x",
")/2, but we can do this for any N, it'd just be bigger. We're going to try to integrate the function f(x)sin(x) from x=0 to pi. ... | [
"Assume that pi=A/B, is rational. For any positive integer N we can then make the polynomial",
"So if N=2, this would be x",
"(A-Bx)",
"/2 = (B",
"x",
"-2ABx",
"+A",
"x",
")/2, but we can do this for any N, it'd just be bigger. We're going to try to integrate the function f(x)sin(x) from x=0 to pi. ... |
[
"If caterpillars turn to \"soup\" during metamorphosis, how can butterflies possibly remember what they learned as caterpillars?"
] | [
false
] | I stumbled upon this claiming that some butterflies can remember things they have learned as caterpillars. At the same time it states that the caterpillar turns into "soup" and that the whole nervous system is rearranged during metamorphosis. How is this possible? Where are those memories physically stored without corr... | [
"From this article:",
"Basically, the caterpillar doesn't completely dissolve away. Instead, the caterpillar breaks down certain tissues and reconstitutes the localized pools of proteins that result into the adult form.",
"The above article links to this ",
"video",
" with 3D scans of within the chrysalis, ... | [
"We can't possibly know what insects \"feel\", but there are some very good indications that they do not feel pain--certainly not in the same manner that we humans do. Consider that an insect that loses a limb or receives bodily damage does not \"limp\" or double over in pain. They typically continue to eat and mat... | [
"I think you may have misread the article. It claims that the idea of retained memory actually refutes the idea that caterpillars are turned to \"soup\". Says right here, \"it challenges a broadly-held view of metamorphosis -- that the larva essentially turns to soup and its components are entirely rebuilt as a but... |
[
"Do blind people see visuals on psychedelics?"
] | [
false
] | [deleted] | [
"Apparently blind people see geometric patterns and other light effects regularly as their brain appears to compensate for lack of sight.",
"http://www.bbc.co.uk/news/blogs-ouch-31667121",
"So they already have visuals without psychedelics, this doesn't answer your question of course, but it's interesting all t... | [
"I feel like they would. I remember a thread on the topic you could probably find it by googling, or I will and link it. It was a story about the OP giving his blind from birth brother DMT because they were both interested in what would happen. Then apparently he was all crying hysterically talking about how beauti... | [
"It probably also depends on why the person is blind. Blind from birth, blind from retina or optic nerve damage after sight, or blind from brain damage. Blind from birth, the person would have no previous knowledge of sight. So maybe, maybe not. Blind from retina or optic nerve damage would leave the person with fu... |
[
"Is the oil on the moon Titan made in a different way to the oil on Earth?"
] | [
false
] | Can it be used the same way as oil from earth? | [
"Titan is mostly covered with methane and ethane. On Earth, when discussing energy applications, that comes closest to natural gas, which is mostly methane with a bit of larger molecules. Petroleum, the black thick liquid, is comprised of larger hydrocarbon chains."
] | [
"Here's a thought. The real trick though is burning all those hydrocarbons.",
"You need free oxygen for that. "
] | [
"Why would you go all the way to Titan to use 19th century technology?"
] |
[
"Is there a mechanism for alcoholic blackouts?"
] | [
false
] | [deleted] | [
"\"Memory disruptions by alcohol leading to blackout have been linked to inhibition of long-term potentiation, particularly in the hippocampus, by affecting gamma-Aminobutyric acid (GABA) and N-methyl-D-aspartate neurotransmission\" from: ",
"http://en.wikipedia.org/wiki/Blackout_(alcohol-related_amnesia)"
] | [
"Basically the hippocampus which is responsible for storing new memories stops working. Also the frontal lobe stops sending out inhibitions. Other parts seem less affected so you still \"seem yourself\" albeit your 'drunk self'."
] | [
"Thank you."
] |
[
"Which organisms have a high ratio of mature mass to sperm+egg/seed/starting mass? Does this tell us anything useful?"
] | [
false
] | [deleted] | [
"Comparing across very different taxonomic groups is not very helpful. The 70kg of an adult human and 100,000kg of a mature giant sequoia do not represent the same thing at all. The majority of the sequoia's mass is non-living material in the trunk while both the human and the sequoia also have shed large amounts o... | [
"For one interesting case I would look up ants and in particular leafcutter queens of genus Atta. ",
"An Atta queen stores all the sperm she will need for her entire life in just one mating flight at the beginning of her life. She stores enough to make 300,000,000 offspring over many years. ",
"Kiwis are speci... | [
"Ants don't seek genetic variation, inbreeding isn't an issue and conformity drives the colony."
] |
[
"How far does Earth's gravitational field extend?"
] | [
false
] | I'm just curious as to how far out Earth's gravitational field extends. I realize that it probably goes out really far but I'm more concerned with the distance at which is pretty much becomes negligible. The planet has some sort of minute effect on the vast reaches of our solar system (and I'm sure when you really get ... | [
"In theory, it extends infinitely in all directions. At a distance 10 times Earth's radius (from the center of Earth) it drops to about 1% of its surface strength."
] | [
"Okay, thank you very much. "
] | [
"When it becomes negligible really depends on the surroundings and on the objects.",
"For a small object on the moon, earths gravitational field is mostly negligible."
] |
[
"Is there any research backed evidence to the claim that unused muscle turns to fat? If so, how exactly do muscle fibers turn into fat tissues?"
] | [
false
] | null | [
"Muscle cells do not turn into fat cells. Large amount of muscles cells require extra resources to maintain. If unused the body will break down the proteins into amino acids for other uses. The idea where this came from was usually someone who stopped working out continues to eat the same diet. This results in exce... | [
"No, muscle fibers do not turn into fat tissue."
] | [
"Actually, I believe I've seen some studies showing that the number of fat cells actually increases if you're growing very fat. I don't have a link, sorry, so take it for what it's worth."
] |
[
"Is the phenonemon of \"childhood imaginary friends\" present in all human cultures?"
] | [
false
] | null | [
"whereas with a country like Japan, where a greater amount of the population tends to live close together, finding real social companions is a lot easier.",
"You haven't been to Japan have you? Nobody does forever alone like the Japanese."
] | [
"Here are a few reports on location-specific prevalence:",
"65% in the United States, 46% in United Kingdom",
"10% in Japan"
] | [
"Is there any correlation in that the percentages increase in countries where the population is more spread out? Something like, the more spread out the population in the more likely you are to fill in the social void with imaginary friends, whereas with a country like Japan, where a greater amount of the populatio... |
[
"Is there a limit to how many atoms there can be in a molecule?"
] | [
false
] | null | [
"Depending on your definition of molecule, it's pretty clear there's no limit in a practical sense. Crystals are essentially giant molecules, if by that we mean continuous blocks of atoms connected by sharing electrons. (Blocks of metal could also count.)",
"There's no fundamental difference between that and what... | [
"The Schwarzschild radius scales linearly with mass, for a long chain of molecules the mass scales linearly with length, so we never get a black hole. It would be unstable against perturbations, however, and might lead to individual clumps with broken chains in between."
] | [
"Most polymers are considered to have a molecular weight of “infinite” because they are so crosslinked. Basically any piece of cast plastic that doesn’t stretch can be considered one molecule. ",
"In technical terms, I don’t think it’s possible to follow the chemical bonds like a maze from one end to the other. ... |
[
"AskScience AMA Series: We're Competing to Make the Mars Habitat Food Production System! AUA!"
] | [
false
] | We're the Auto Terra Project, one of the top 25 teams in the US competing in the NASA Deep Space Food Challenge, a competition to create the Mars habitat food production system. This system will be used to feed the astronauts at every step of the mission. You'll see us listed on their website as the Arrakis Terrarium... | [
"Zero maintenance sounds like an over sell, is it truly zero?",
"Isn't this concept basically the same idea as those ridiculously over-priced aerogardens?"
] | [
"Can confirm that it’s 0 daily maintenance. Time sinks after assembly would be resetting the system and harvest. A system reset takes ~40 minutes with makeshift tools, and a full harvest takes 2.5 hours with me documenting, weighing, photographing, and beginning to prepare samples for testing as I harvest. Cooking ... | [
"To clarify, system reset refers to planting the system again. The trigger is that the user wants more food!",
"It's not easy to say how often this would need to be done, as it depends on the program being run, though the absolute shortest program that it can run is 35 days. Right now, we're running 35 day cycles... |
[
"Why is there a shingles vaccine but not a herpes vaccine?"
] | [
false
] | And if a herpes vaccine came out, could it help people already infected? | [
"Herpesviruses in general are large, extremely complex viruses that are ancient (the family is hundreds of millions of years old) and that have evolved with their host species for tens or hundreds of millions of years. Their life cycle means that they are naturally adapted to evading and overcoming immunity, since ... | [
"There is some promise with a new vaccine that is headed towards human trials.",
"I worked on herpes simplex in the early 1990s, and came back to it briefly about 15 years later. The conferences I went to in the 2010s could have been lifted from the 1990s - same topics, same level of understanding, same number of... | [
"herpes and shingles are actually pretty similar viruses, that's why the comparison"
] |
[
"Can I/should I use the work \"hack\" in the \"lifehack\" sense in a chemistry/biology journal?"
] | [
false
] | null | [
"Not the right sub"
] | [
"Thought it would be the most published audience. Any recommendations?"
] | [
"Maybe try ",
"/r/askacademia"
] |
[
"How do we know the required Delta V to get to distant planets or the moon?"
] | [
false
] | My question comes from my teacher asking if any students don't believe in the moon landing. I as a believer in such events took place, am still curious on how we knew how much delta v it took to land on the moon in the first place, and later on to Mars and Jupiter? | [
"Distances can be calculated in a number of ways. Aristarchus calculated the distance to the moon in the 3rd century BCE by observing the moon during solar eclipses (the size of the Earth was already known by then, and so he was able to determine the distance and size of the moon by observing the earth's shadow on ... | [
"Math, and the laws of Gravitation. We know that a certain amount of Mass will exert a certain amount of gravitational effect. From there we can extrapolate the Delta V for just about any target. As long as all the designers are using the same units, that is. "
] | [
"Speed of light. It's a universal constant. So we can use it to measure distance by how long it takes for light to reach a certain body in our universe. And because the amount of light from our sun isn't constant, we can measure differences in time between it's effects on other objects in our solar system. Which gi... |
[
"When does it make sense to turn off a computer instead of putting it in sleep mode?"
] | [
false
] | I was raised by penny-pinchers who'd have a conniption if I left a light on when I wasn't in the room, so by habit I always turn off my computer when I leave for the day or go to sleep. However, I've been told by tech-savvy people that the process of booting up a computer is considerably more intense and stressful to t... | [
"The most likely component to fail from power cycles would be the hard drive. However, the most definitive work I know of has this to say:",
"Power Cycles. The power cycles indicator counts the number of times a drive is powered up and down. In a server-class deployment, in which drives are powered continuously, ... | [
"People used to say that because solder points can potentially crack from repeated temperature changes. I haven't heard anyone give that advice since the 90's though. Computer components generally have a lot of redundancy built in. It's doubtful you'll keep anything long enough for this to be a problem. If somethin... | [
"The wear on startup really isn't significant. Most people get rid of their PCs long before that becomes a consideration. Consider that a standard power saving setting for years has been to turn off the hard drives after a period of idle. That wouldn't be as likely if it killed your drive.",
"This link",
" shou... |
[
"Is there a way to ensure a gun in storage can never be pulled out and used?"
] | [
false
] | null | [
"Thanks!"
] | [
"Remove the trigger?"
] | [
"This isn't the right place for this; ask in ",
"/r/guns",
". They are very nice.",
"And yes, you can disable a gun discretely such that it will not fire. The gun people will help ya.",
"Best of luck from all of us. :("
] |
[
"Why do muscle cramps hurt?"
] | [
false
] | I understand that muscle cramps are involuntary contractions of the muscle, but when our muscles contract voluntarily, it doesn't hurt. What about an involuntary contraction causes pain? | [
"There are a few things going on, but the most prominent when it comes to pain are lactic acid buildup from anaerobic processes causing localized irritation, and pressure sensors in the muscles going a bit mad and sending frantic overload signals. Beyond that, you have the normal complement of sensory nerves being ... | [
"Make a fist, and squeeze as hard as you can. Now hold it for as long as you can. You'll find that your hand quickly gets tired, and then soon starts to hurt. The pain stops almost immediately after relaxing your hand.",
"Muscle cramps are exactly the same. Your muscle contracts uncontrollably, and doesn't relax ... | [
"Can it be damaging if a muscle is cramped for an extended period of time?"
] |
[
"Is there a biological or evolutionary reason why sex is associated with the night or is it more societal?"
] | [
false
] | null | [
"This is a friendly reminder from your moderator team not to speculate and to only answer if you can back up your answer with scientific evidence that you fully comprehend."
] | [
"A study published in the Journal of Circadian Rhythms concluded that",
"although the presence of an endogenous component responsible for this temporal pattern cannot be excluded, the evidence indicates strong environmental forcing, particularly from the work/family schedule of the individuals and from partner av... | [
"why don't you just post normal comments"
] |
[
"Is air brought in through the nose cleaner than air brought in through the mouth?"
] | [
false
] | null | [
"It could be that breathing in through the nose warms the air before it reaches your throat, but mouth breathing lets the very cold air directly hit the throat?"
] | [
"Short answer: yeah, probably.",
"Long answer: it probably doesn't make much of a difference. The upper airways are basically lined with a mucous filter. The vast majority of particles are going to be trapped by that filter before it goes away in the lower airways. Breathing through your nose effectively exten... | [
"This may be a result of dry air, rather than contaminated air. Your nose not only warms the air, it also makes sure that it is not too dry. When you breath in cold air it will get warmed inside your body and its humidity will drop (and humidity is probably low to being with). So when breathing through the mouth yo... |
[
"I just finished Stephen Hawkings newest book “Brief Answers to the Big Questions” and I’d like to get an opinion on it and Stephen Hawking in general. I’ve heard a lot of praise for him but I’ve also heard criticism. What is the consensus on him as a scientist?"
] | [
false
] | null | [
"What criticism have you heard of his scientific work? "
] | [
"If this is an accurate account of your exchanges, then your friend is clearly not an expert in the subject and does not have the proper background to offer any sort of scientific critique. For instance, scientific theories are not \"upgraded\" to laws, as your friend's comments suggest. Your friend also clearly do... | [
"I'd ask their permission before doing so.",
"I should mention: Hawking has little-nothing to do with string theory and only his most recent works on black holes are remotely controversial. "
] |
[
"What would happen if a temperatures like the Sun's Were found here on earth?"
] | [
false
] | null | [
"If you are just looking for something that is high temperature, you need look no further than a lightning bolt. They are much hotter than the surface of the sun."
] | [
"We can artificially produce temperatures that high. Usually, it is done with much smaller objects, but there's no reason it couldn't be done with one the size of a basketball (there just isn't a real reason to do it, as that's larger than any sample you'd need, so it'd be a waste).",
"It wouldn't cause fusion, ... | [
"What if it was a ball of plasma at that temperature? Wouldn't the electrons be removed so the repulsive force between two nuclei wouldn't be there?"
] |
[
"How do you figure out the magnitude of a length contraction?"
] | [
false
] | null | [
"The formula is very simple, and given in the first paragraph on wikipedia: ",
"https://en.wikipedia.org/wiki/Length_contraction"
] | [
"Figured it out, cheers. Just a question, would the driver be able to measure the length contraction using on board equipment only? "
] | [
"The driver can ",
" the contraction given their velocity, which you certainly could get from on-board equipment. But the driver will not ",
" the length contraction -- at no point will he notice \"oh, my ship is shorter\". This effect is from the observer's perspective only."
] |
[
"What is the psycological process that happens to recruits in boot camp called?"
] | [
false
] | [deleted] | [
"Indoctrination.",
"Which is, incidentally, even the term that the military uses itself."
] | [
"so you're absolutely not a U.S. Marine."
] | [
"This is a misconception; being \"broken down and built up again\" is an oversimplification of the process that happens at BCT. It isn't brainwashing or programming. It's being taught how to conform to a military lifestyle. However, several psychological learning techniques are used:",
"Calling it \"classical con... |
[
"What does it mean for a black hole to be rotating?"
] | [
false
] | It seems unintuitive to me to describe a single point as rotating. In what direction does a singularity rotate? | [
"Rotating black holes are believed to have a ring-shaped singularity, or Kerr singularity, because as you suspected a point cannot have angular momentum in classical physics.",
"However, quantum mechanics does allow for point particles to have angular momentum. This angular momentum called spin is an intrinsic pr... | [
"The particle doesn't literally spin, even in quantum mechanics a point particle can't rotate, but it still has angular momentum. This is one of those cases where intuition based on the macroscopic world doesn't really apply."
] | [
"I've always been bothered by the fact that we don't talk about Kerr black holes by default, since there should be literally zero non-rotating (i.e. Schwarzschild) black holes in the universe/reality. For instance, the black hole we imaged recently, M87, would be a Kerr black hole, correct? So wouldn't it also have... |
[
"Why does a motor draw more amps when it has a higher load?"
] | [
false
] | null | [
"the higher the load, the greater the torque required to turn it at the same rpm.",
"all other things considered equal, higher torque means higher force. to produce higher force at the rotor, you need higher magnetic field flux density. and for greater magnetic flux density, you need more current."
] | [
"Think of an electric motor as a power converter. If you want more mechanical power output, then it needs more electrical power to the input. You can't get something for nothing. It's sort of like how you have to push down more on the gas pedal in your car when you're going up a hill compared to going on level g... | [
"Just to add on, usually synchronous motors are the ones that will draw more current under more load. An induction motor will draw close to the same all the time but will slow down. You will probably see more induction motors in plants due to that fact because they don't want to pay for the increase. "
] |
[
"How far would one of my atoms likely have travelled, on average, before it became me?"
] | [
false
] | I am not sure that it is even possible to calculate a ball park figure, but owing to the fact that my atoms were forged in stars, sometimes through multiple generations, before being exploded into space and eventually ending up as a part of me there must actually be an answer. How many light years away were these explo... | [
"How far has an atom traveled relative to ",
"? I'm assuming that we only care about the distance traveled in the galaxy, which comprises mostly revolution around the galactic center.",
"Because the milky way is estimated to be nearly as old as the universe, it's very likely that the atoms came from supernovae ... | [
"the sun has most certainly not 'gone supernova before'"
] | [
"And exactly where is the center of the universe? Due to the metric expansion of spacetime, there ",
".",
"That's the meat of my \"relative to ",
"\" clause. "
] |
[
"We all know that humans share 98% of our DNA with chimpanzees. But what do we share 75%, 50%, and even only 10% of our DNA with?"
] | [
false
] | [deleted] | [
"Here are some examples:",
"Mice 75% ",
"http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1000112",
"Fruit fly 60% ",
"http://www.genome.gov/10005835",
"Bacteria 35% ",
"http://www.theforbiddenknowledge.com/hardtruth/genetic_accounting.htm",
"Lettuce 16% ",
"http://ask.metafilter.com... | [
"Furthermore, what does \"Share 98% of our DNA with\" mean?",
"For instance, if I have a gene with DNA for Cyteine \"UGU\" in a specific spot, and you have Arginine \"CGU\" do we share 2/3 of our DNA in that particular spot (because 2/3 of the base pairs are equivalent) or 0% (because we code for something comple... | [
"To the extent that we can meaningfully and reliably answer this question (this is not my area of expertise!), check out ",
"this",
" at nature.ca and ",
"this",
" from 23andme.com. The two sources give similar, though not identical, results.",
"Quick summary (2 numbers if both sites give a value, one nu... |
[
"Would it be possible to use an old transistor radio to detect passive RFID tags?"
] | [
false
] | I know passive RFID tags dont use their own power to emit a radio signal since they have no external battery. Would it be possible to detect any type of signal with an transistor radio if I got close enough to the tag? Would there be static or anything? Thanks | [
"They don't output anything unless they have power. If you could build a device that simply sends out the EM waves that power the tag, then you could probably pick up the response with your radio, but without powering the tag, you will get nothing."
] | [
"Both actually. Neither your radio nor the passive RFID tag will output anything without power. You need a power cable/battery for your radio and the correct EM waves for the tag in order to power them and make them work.",
"Outputting any signal, be it radio signal or sound signal, takes energy."
] | [
"You are mistaken about one thing. You are right that the RFID tag gets its power from waves, but it is not sound waves. It is radio waves.",
"Radio waves are waves of Electromagnetic radiation (they are really a form of light) while sound waves a physical waves of air pressure. The radio you have receives (you c... |
[
"What are the biggest misconceptions about scientific inquiry?"
] | [
false
] | null | [
"Hi cldavies 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 follow... | [
"Thank you for your submission! Unfortunately, your submission has been removed for the following reason(s):",
"/r/AskScienceDiscussion",
"Please see our ",
"guidelines.",
"If you disagree with this decision, please send a message to the moderators."
] | [
"Thank you kindly for the help. I will post the question there."
] |
[
"Wouldn't the machine in the Schrödinger's Cat thought experiment be \"observing\" the state of particles, therby collapsing their superposition before doing anything to the cat?"
] | [
false
] | I don't know a whole lot about quantum physics, so sorry if this question just reveals a fundamental lack of understanding :D But it always seemed to me like the obvious answer to why the cat is not simultaniously dead and alive. Observation in the Copenhagen interpretation doesn't require a human being to read the dat... | [
"Yes, and that gets at how the thought experiment would actually work in real life. The box does not completely isolate the cat from the rest of the universe. There are still irreversible interactions going on constantly, where the “environment” (the rest of the universe besides the cat) is essentially measuring th... | [
"Yeah, in AMO experiments. These are often things like clouds of a few atoms in a trap, in ultrahigh vacuum.",
"Every experiment is different in terms of its limitations, but if it were easy to do with larger systems, people would be doing that."
] | [
"My understanding is we've isolated small systems from the rest of the universe for QM experiments, is that correct? If so, why can't those scale up well? ",
"It seems like once you learn how to isolate a small volume of space, it shouldn't be fundamentally more difficult to isolate a larger volume. But I'm super... |
[
"Why arent helicopters streamlined top to bottom, instead of forward to back?"
] | [
false
] | it just seems more fuel efficent if the streamline goes that way, then the rotors arent pushing against the body of the helicopter so much | [
"There are practical considerations, such as passenger space, stability (when landing/landed), structural rigidity, etc. that all need to be considered. A sleek top-to-bottom cabin would not satisfy any of these requirements.",
"\nAlso, the velocity close to the hub is much lower than at the tips. Since helicop... | [
"1) To a certain extent, they are.",
"2) The downward-moving air from the rotors is pretty turbulent, there wouldn't be as much advantage to streamlining."
] | [
"Because of two reasons:",
"\n1. Streamlining it would mean the Helicopter would be taller which would result in its center of gravity be lower. That would make it a lot more unstable for landing.",
"\n2. And this probably the MAJOR reason: It simply would not gain you much efficiency. Don't think that the circ... |
[
"What is the science behind the introvert-extrovert model of social interaction?"
] | [
false
] | I have been seeing the terms "introvert" and "extrovert" used with increasing frequency as a physical diagnosis of one's capacity to interact with other people. Terms that evoke batteries--like "energy" and "recharge"--are used and there seems to an emphasis on this idea that people can be physically drained or energiz... | [
"Personality types are not a good predictor of individual behavior. It is found that people act differently from their personalities when faced with strong situations. It is possible that personality traits like introversion and extroverted are just learned behaviors influenced by the situation that the individual ... | [
"Carl Jung used the term in his theory of archetypes, which were later used to develop the Myers-Briggs personality profile.",
"A more recent personality theory, called the \"Big Five\", is proposed to be a better alternative, and it asserts that the Jung and the Myers-Briggs models are not accurate."
] | [
"This argument arose during the situationist debate. Today it's generally agreed that situations do indeed exert pressure on our behaviours, but our personalities determine in what manner we respond to such pressure. That is, given equal ",
", people will respond differently. However, in intensely stressful situa... |
[
"Will the Earth eventually become tidally locked to the moon as the moon is to Earth?"
] | [
false
] | null | [
"I believe that the Wikipedia article linked implies that the answer is yes, provided that there is no other body exerting sufficient influence to disrupt the process, and that the system lasts long enough. The article notes that the Earths rate of rotation is known to have slowed due to the tidal locking effect, a... | [
"I am amazed at how bad that website is. That is a genuine US government site? I presume you linked it for its comedy value?"
] | [
"Awesome, thanks for the clarification "
] |
[
"Does heat, humidity, and other atmospheric variables affect wi-fi and other signals?"
] | [
false
] | null | [
"Water vapor does, but only slightly so to be unnoticeable. Water vapor (i.e., humidity) absorbs microwaves in the 3-5 GHz range only on the order of 0.001 dB per km. For a typical cell tower with 100 km range, this means humidity is only changing this range on the order of 1 to 10 meters or so. ",
"Rain or ha... | [
"If you're interested in other variables like light or sound, you might be surprised at how much the signal are affected. Stars can twinkle at night due turbulence, or random winds. Wind will also \"push\" sound. The temperature and humidity will also change the speed of sound. Based on these principles, there ... | [
"To further expand, the stars twinkle due to shifts in the refractive index of the atmosphere as air of different temperatures and humidities moves between you and the star."
] |
[
"How did they find the exact boundaries of tectonic plates?"
] | [
false
] | null | [
"Earthquake distributions get you most of the way there, e.g., compare ",
"the locations of earthquake",
" with that of ",
"plate boundaries",
". More recently, definition and identification of individual plates (along with understanding directions of motion) have been aided by a variety of geodetic data, c... | [
"Seismic tomography",
", which exploits changes in seismic wave speed as a function of temperature and other properties to \"image\" the interior structure of the lithosphere and mantle, can help fill in some details of the geometry of plate boundaries with depth, but I'm not aware of an application where it's be... | [
"CrustalTrudger comes through, as usual.",
"I would add only that I had the opportunity to participate in several seafloor mapping projects using side-scan sonar, and we mapped out some of these plate boundaries on the East Pacific Rise, Gorda Ridge, and Juan da Fuca Ridge. Actually \"flying\" the instrument thro... |
[
"If carbon dioxide was once 20 times as prevalent in the atmosphere as it is now, why should we be concerned."
] | [
false
] | I was just doing some reading on wikipedia and at in the article on carbon dioxide I learned that 500 million years ago it was at 20 times its current level and during the Jurassic era it was 4 to 5 times its current level. The same brief three paragraph section also says that there are about 3,160 billion tonnes of ca... | [
"well, it's not that increasing carbon dioxide levels will destroy all life. If it spikes too quickly, it may cause a mass extinction of sorts. But life will still persist, and evolve into something different. ",
"The threat is that we will turn the earth into an environment where we can't survive. It's a threat ... | [
"We're probably not even talking about an existential threat to the human race itself, but there's definitely some potential dangers to our modern civilization. Significant climate change could make life difficult and even unlivable in many crowded places, and would probably cause refugee migrations way beyond anyt... | [
"A couple of things:",
"500 million years ago, the sun was dimmer than it is today. Raising CO2 to the same level would make Earth hotter than it was then.",
"500 million years ago, we didn't have billions of people living within a few meters of sea level, and billions more depending on an already strained food... |
[
"Is the strong force stronger between proton and proton than proton and neutron? If not, is it easier to eject a proton from the nucleus than a neutron?"
] | [
false
] | null | [
"Great question, and the answer is that it depends.",
"If you look at the properties of the proton and neutron, they are ",
" identical (in terms of mass, quark content, spin, etc.), except for the glaring difference that the proton has electric charge and the neutron doesn't.",
"However the nuclear force bet... | [
"I just want to clarify that even though the math of spin and isospin is more or less identical, isospin has nothing to do with angular momentum.",
"I keep seeing this (or variants of this) used to explain that the quantum notion of 'spin' is different from the classical notion of spin. I've said similar things. ... | [
"I keep seeing this (or variants of this) used to explain that the quantum notion of 'spin' is different from the classical notion of spin.",
"Well that's a different concept. Spin in QM doesn't mean that something is literally \"spinning\", however it is a totally legitimate angular momentum in any sense.",
"I... |
[
"Why are high performance computers considered more powerful than the next gen consoles, but are unable to run even previous generation emulators (PS3, Xbox 360) at appropriate efficiency?"
] | [
false
] | null | [
"Architectural differences. The emulator tries to translate the instructions from the console architecture to the PC architecture. This takes a lot of overhead as potentially millions of instructions have to be translated per second. ",
"I'll try to explain it as simply as possible.",
"Say you understand both S... | [
"Yeah. \"older\" consoles have a Powerpc architecture and desktop cpu's usually use the x86 architecture. It's a bitch to convert one to the other. The only recent console that can be properly emulated at the moment is the Wii. Not only is it not very powerfull, it is verry similar to the gamecube so there already ... | [
"Architecture for a start. And I know that the PS3 uses a 7 \"core\" processor which cannot be emulated at the moment. Its not a GPU issue for sure, but a CPU compatibility issue.",
"I believe the same is also true of the 360, but the 360 CPU has less \"cores\". I'm not 100% on that though.",
"We can get there ... |
[
"Why does my ipod's battery gauge fluctuate so unpredictably?"
] | [
false
] | This happens to both myself and friends and particularly whilst playing applications for more than a minute or two. Soon after stopping playing it, the battery returns from the below 20% area. Why? | [
"Electronic devices generally measure the battery voltage and convert this to some sort of pseudo remaining energy measurement. Under a steady load for the entire run time, this may be accurate, assuming a linear scenario.",
"Due to a battery's internal resistance, however, heavy loads will bring down the measure... | [
"Your battery gauge measures the voltage of your battery, and while it is a fairly good indicator of how much charge is left in your battery in an ideal world, things such as mass transport plays a hand in the real world.",
"Normally, a cell's voltage is determined by the ",
"Nernst equation",
" - it is depen... | [
"This is reasonable, thank you. I'm quite happy I managed to follow most of it. Quite often the jargon in askscience is a repellant. It also explains why the reading fluctuates less when doing less strenuous tasks like just listening to music.",
"Thank you for your comment, I was always curious to this."
] |
[
"Why do estrogen levels drop before ovulation and then rise again after?"
] | [
false
] | What is the purpose of the dip; why doesn't estrogen just stay elevated? | [
"Hopefully an actual scientist will chime in here, but broadly the drop in oestrogen signals to the ovaries that the woman is not pregnant to get them to release a new egg. The combined pill (containing oestrogen) tricks a woman's ovaries into behaving as if she's already pregnant so that no egg is released."
] | [
"Perfect answer! Makes complete sense thank you"
] | [
"Perfect answer! Makes complete sense thank you"
] |
[
"I just shattered a Corelle plate on my granite counter top, why did the plate pieces start jumping around?"
] | [
false
] | It looked almost like popcorn being popped. | [
"That would also be my ",
" as well. Corelle plates have glazes on them so the glazing process alone probably leaves some sort of residual stress. Without more info I can only speculate though. I'd love to see the broken pieces. You can tell a lot from fracture surfaces (macroscopic scale even)."
] | [
"Probably residual stresses being relieved. IIRC, ceramics, especially tempered glass for example, can build up a lot of residual stresses that balance out in the bulk part. When the object is broken, there is suddenly nothing stopping the residual stresses being relieved, and they'll slowly propagate a crack throu... | [
"We have legit ceramic experts on reddit?!"
] |
[
"Since being nervous raises your heart rate, does it have the same benefits as exercise?"
] | [
false
] | null | [
"While the two activities will both raise your heart rates, there are many other physiological differences between the two activities. When you exercise, your heart rate increases rather gradually, at least at a rate in which your body can withstand (most of the time). Nervousness brings about a very sudden increas... | [
"He/she is ask"
] | [
"Another thing is, increase in heart rate is accompanied by increase in breathing rate during exercise. This is because your heart rate increases to deliver more oxygen and immediate sources of sugar, ATP, calcium ions, and numerous other forms of energy the cell uses, to your body. Therefore, working your respirat... |
[
"Can you throw something hard enough to escape the Moon’s gravity with your arm?"
] | [
false
] | This post was inspired by the “space harpoon” that speared some of the debris orbiting Earth. Could someone hurl something like a javelin on the Moon hard enough to escape the Moon’s gravity?, how close could they get? | [
"The Moon's escape velocity is about 2.4 km/s. By comparison, the Earth's escape velocity is about 11 km/s.",
"The fastest baseball pitch on record was less than 50 m/s, or 0.05 km/s. The fastest golf shot on record is less than 60 km/s. So we're not even close - you'd have to go to an asteroid rather than the Mo... | [
"Correction: world record for golf ball speed (Ryan Winther 2012) is 226.7 mph or 0.1 km/s"
] | [
"The fastest baseball pitch on record was less than 50 m/s",
"And if you throw baseball up with that speed it would go nearly 800m up in the vertical direction."
] |
[
"How does \"star tripping\" work? Is it dangerous?"
] | [
false
] | null | [
"If you spin until you feel dizzy, you are upsetting your vestibular system (the fluid-sensing section of the inner ear that helps you detect acceleration and remain balanced).",
"At a guess: shinning a bright light in someone's eyes, after that person has been focused on a faint light in dark surroundings (a sta... | [
"So wait… since the video showed nothing but a long sequence of black on indistinguishably dark shades of gray seasoned with childishness…",
"How do you look at a star ",
" spinning? Or do you look at it, and ",
" spin around?",
"And no… One has to be really retarded to think it can cause seizures or brain ... | [
"So wait… since the video showed nothing but a long sequence of black on indistinguishably dark shades of gray seasoned with childishness…",
"How do you look at a star ",
" spinning? Or do you look at it, and ",
" spin around?",
"And no… One has to be really retarded to think it can cause seizures or brain ... |
[
"How do we calculate numbers to an irrational exponent like x^pi?"
] | [
false
] | null | [
"The way calculators do it is not so straight-forward actually. Although in theory everything that has been put forward in the answers here is equivalent to one another, that works only in arithmetic with infinite precision (which is what all theorists and even most applied mathematicians think in). Once you go to ... | [
"The way calculators do it is not so straight-forward actually. Although in theory everything that has been put forward in the answers here is equivalent to one another, that works only in arithmetic with infinite precision (which is what all theorists and even most applied mathematicians think in). Once you go to ... | [
"If you’re asking how exponentiation is defined on irrational numbers, it’s just what you might expect. For any irrational number, there’s only one value that makes the function continuous, or smooth, and that’s what it’s defined to be.\nTo calculate it, what you said works. However, there isn’t even a very clean a... |
[
"According to latest news, Moderna's vaccine creates more antibodies than Pfizer's, but they show similar efficiency/efficiency. Why?"
] | [
false
] | null | [
"Antibodies are proteins that specifically bind to certain antigens (parts of viruses or bacteria) and help identify those invaders as harmful, signaling the body, through the use of white blood cells, to destroy that invader. Think of them kind of like puzzle pieces looking for the right match. They're just floati... | [
"First: The studies suggest that Moderna gave around twice the antibody level. Some write-ups called that a large difference, but to me that's a barely measurable difference for antibodies. Depending on how you're measuring antibody titers, you'd often be happy to be able to spot a 5-fold difference. So though the ... | [
"Does this affect the length of efficacy though? If your security people die off at a certain rate, you’ll be above that threshold for longer?"
] |
[
"What happens to our body when we train ourselves to hold our breathe for longer periods of time?"
] | [
false
] | null | [
"If you do it repeatedly over a long period of time, you get brain damage. From the New Yorker article ",
"Pushing the Limits of Extreme Breath Holding",
":",
"François Billaut, a French researcher at the Université Laval, in Quebec City, ",
"published a paper",
" examining the effects of apnea on cognit... | [
"Lol \"somebody technically almost drowns and suddenly it's a safety concern.\""
] | [
"We did the same thing on our swim team. One girl passes out on the bottom of the pool and suddenly its a safey concern.."
] |
[
"What would it take to land a telescope on the moon, and how well would it work?"
] | [
false
] | Would it be possible and practical to land a telescope on the moon, and how well would it work? | [
"It's an idea that's been taken seriously. The Moon is tidally locked with Earth, which means its rotation is perfectly in sync with its orbit, and one side of the Moon permanent faces away from the Earth. So the far side of the Moon is permanently free from any interference from light or radio waves from Earth. It... | [
"There are some good comments already on this thread. They are focusing on two main points:",
"Both are right.",
"To expand on #1, usually the \"delta-v budget\" is considered when planning a space mission. First you need to get your payload to Low Earth Orbit (LEO). From some space telescopes this might be eno... | [
"There has been a few of small scale telescopes landed on the moon. But I think an important consideration has to be why you would want to place your telescope on the moon.",
"Remember that it takes an enormous amount of energy (=money) to get a telescope into space. Getting it to the moon, and landing it, makes ... |
[
"I got the Moderna vaccine ~6hr ago. How many spike proteins have my ribosomes produced in this time (order of magnitude)?"
] | [
false
] | null | [
"The Moderna vaccine contains 100 µg of mRNA, with a length of about 4000 bases. This is equivalent to 4.7*10",
" copies (based on ",
"this calculator",
").",
"Let's assume that 1% of that makes it into your cells and starts being translated. (If anyone has better information about this, please let me know.... | [
"This is assuming it all went into cells at time of injection. Instead, they travel by lymphatics (mostly) and eventually wind up mostly in the liver [EDIT - it's actually quite a few places, (here's a good review - ",
"https://blogs.sciencemag.org/pipeline/archives/2021/01/21/mrna-vaccines-what-happens",
") ] ... | [
"Just to add to this, just because a ribosome translates the mRNA into protein doesn't necessarily mean it is properly folded. A unfolded polypeptide often needs a chaperone to help it properly fold, and this process ",
" take some time. Translated but unfolded spike protein is likely biologically inactive - the ... |
[
"What experiments have been performed which lead to the theory that time is affected by gravity?"
] | [
false
] | I remember this being in 'A Briefer History of the Universe' by Hawking, but can't remember the exact experiments. | [
"Numerous ones. The first one you could name, I suppose, ws Pound-Rebka, which was actually quite clever, but indirect. It measured gravitational energy shift in photons, not gravitational time dilation directly.",
"But the most famous is Hafele-Keating. Very precise clocks were installed on planes and flown arou... | [
"Oh, it's completely arbitrary. Seconds aren't ",
" They're just units. We take a certain duration — from now to ",
" — and declare that it's equal to \"one second.\"",
"You can read up on the history of timekeeping if you like. It all goes back to the duration between one sunrise and the next, of course, and... | [
"With a clock.",
"Seriously. I'm not being facetious. Distance is the thing you measure with a ruler. Duration is the thing you measure with a clock. It's really no more complicated than that … though of course because you can't ",
" a duration the way you can touch a distance, there's an I-suppose-understandab... |
[
"If a person gets two different types of COVID vaccines, does their immune system know that they are for the same virus?"
] | [
false
] | null | [
"If this has been answered before can you please link that post?"
] | [
"If this has been answered before can you please link that post?"
] | [
"https://www.reddit.com/r/askscience/comments/husgwe/does_getting_several_different_vaccines_for_the/",
"But that is old and though there are other versions of the question asked like ",
"https://www.reddit.com/r/askscience/comments/iskqt2/with_so_many_covid19_vaccines_using_different/",
" they didn’t get any... |
[
"Why do we have an optic chiasm? Wouldn't it be simpler if the right eye supplied the right cortex and the same for the left?"
] | [
false
] | [deleted] | [
"The left brain processes the right side of the visual field in both eyes, the right brain processes the left side of the visual field in both eyes. The crossing over of incoming visual stimuli and the location that this splitting/mixing occurs is the optic chiasm.",
"It's difficult to ask why sometimes in medici... | [
"There are ",
"good mathematical reasons",
" for why you would want the nerves to cross over. It is, somewhat non-intuitively, a lot more robust against certain types of connection errors."
] | [
"Your left eye doesn't just see left and your right eye doesn't just see right. Instead, they both see ",
"approximately 155 degrees",
". Your occipital lobes are configured to interpret a composite image from both eyes rather than taking an image from your left and an image from your right and pasting them sid... |
[
"How does DNA actually work?"
] | [
false
] | I'm pretty knowledgeable (ish) on biology/evolution, but this is something that has really eluded me. I don't have any sort of grasp on it. I know that DNA essentially acts as a "software" or a "code" for the cell "hardware" to run on... but how does this process actually take place? How does the presence of DNA strand... | [
"There are lots of molecules floating around the cell (proteins) that are like miniature robots and they are in charge of interpreting the DNA code.",
"The first such molecule is RNA polymerase. It (along with TONS of other regulatory or assistant molecules) is in charge of turning DNA into an RNA transcript.",
... | [
"Good. If your mind isn't blown, it's a good sign that you don't really understand the complexity involved. :)"
] | [
"It's all about free energy. An ATP-powered enzyme that cuts up starches into sugars might be a useful example:",
"In this simple model, a protein has two major binding sites: One is for it's ligand (the starch), the other for ATP (the power). After bouncing around for a while, a starch molecule will eventually ... |
[
"Does using stainless steel as an anode in electrolysis really create toxic byproducts as a result of the process?"
] | [
false
] | I have a lot of cast iron cookware that I've collected from places that don't matter in a valiant and foolish quest to use pans that aren't coated with Teflon and other nonsense. Most of them are rusty and encrusted with well, crud. There are a few different ways to remove it, but the easiest and least environmentally ... | [
"If you are using a piece of stainless as a sacrificial anode to remove corrosion from a piece of rusted iron, then the possibility exists that you could make ",
" hexavalent chromium. However, the chances of that happening are pretty small, especially if you make sure to control the voltage. At the anode, you ... | [
"Keep in mind that above 1.23 V, water will dissociate so you might have that reaction occurring instead, or at least one of the half reactions taking place at an anode or cathode. If it is acidic, you might get hydrogen evolution so be very careful if you try to push it above 1.2 V."
] | [
"This is only likely to happen in extremely corrosive solutions that can dissolve the layer of chromium (iii) oxide that forms on the surface. For example, some molten salts, or concentrated hydrofluoric acid.",
"Using bare stainless as an anode often doesn't work well because of the "
] |
[
"Logarithms of complex numbers? Logarithms with complex bases?"
] | [
false
] | I was recently thinking about math, and I realized that I could use Euler's Identity [e = cos(x) + i*sin(x)] to define logarithms of complex numbers. Here's how: those of you answering this question should know that any complex number a+bi can be transformed through Euler's identity into the form re , where r is the ra... | [
"Yes, all of this works, except there's one thing you haven't taken into account:",
"when you write z = re",
", that representation isn't unique, you could take x' = x + 2pi, and z = re",
" as well. Thus, when defining the logarithm",
", you have to be careful and take this into account. You can address thi... | [
"Yes ",
"it has been discovered",
", and yes it is mathematically valid to the extent that you are careful with how you use it.",
"There is an inherent problem with complex logarithm that comes from the fact that exp{x+iy}=exp{x+iy+i2pi}. If you were to naively assume that the complex exponential is invertibl... | [
"\"x is the angle between 0 and 2pi such that z = e",
" \"",
"Of course, this comes with a sacrifice: you no longer have the nice property that log(ab) = log(a) + log(b) (as a counterexample, take a = b = e",
" or something). This is probably the answer to the question \"why do my teachers tell me I can't do ... |
[
"If all vegetation is dead, how long would it take till mankind suffers from a lack of oxygen?"
] | [
false
] | Assume that there are no other problems like food production, just focus on the problem of suffocation. | [
"Ok let me do some math.\nA breath is about 6 L/m. 1/5th oxygen on the way in, 15% oxygen on the way out. That's 0.3 L of oxygen per minute exchanged. Multiply that by 7 billion and you get 2.1 million metres cubed per minute, at STP.",
"The atmosphere is 5E18 kg, which at STP is about 4E18 m",
" total, or abou... | [
"Except it's not just people, but the entire biosphere, plus dead biomass oxidized. Just assume what whatever carbon plants fixate ",
"http://en.wikipedia.org/wiki/Primary_production",
" annualy they no longer do. Subtract that from the 20% or so. I suspect there will be enough organics to make atmosphere anoxi... | [
"I wonder at what point the oxygen content in the air is at a level that we pass out though. Let's say we \"use up\" half of the gross oxygen content in the atmosphere. The remaining oxygen would diffuse throughout the volume evenly, making the oxygen content half by percentage. ",
"At some point we wouldn't stay... |
[
"Speed of light and special relativity hypothetical situation i don't quite understand"
] | [
false
] | null | [
"From O's perspective, yes, A and B are moving towards each other at 1.5",
". However, from the perspective of A, the speed at which B is approaching is somewhat slower than ",
" (although larger than .75",
"), and likewise from B's perspective.",
"This is addressed in more detail over in an ",
"FAQ",
"... | [
"Check out the answer in the ",
"sciencefaqs",
"."
] | [
"That's because you are adding relativistic velocities using a Newtonian formula (aka v1+v2=v3).",
"To add relativistic speeds you need to use: v3 = (v1+v2)/(1+(v1×v2)/c",
" )",
"There is no ether"
] |
[
"The Banach-Tarski paradox explanation?"
] | [
false
] | Is there such an intuitive explanation for this theorem? More importantly, as a college-less adult that has little math expertise beyond Calc I, what do you recommend reading to get a better understanding of this topic? | [
"It's difficult to explain the proof of the theorem itself without getting into free groups and paradoxical decompositions and such. These things require some knowledge of university-level mathematics, even beyond calculus and linear algebra. The proof isn't that difficult at all once you know about those things, s... | [
"This doesn't go into the full details, but it's the only attempt at a somewhat simple explanation that I'm aware of:",
"http://www.irregularwebcomic.net/2339.html",
"Read the text below the comic."
] | [
"Other answers have already covered the basic idea and seemingly paradoxical nature of this theorem. ",
"I'd like to emphasise what ",
"/u/cromonolith",
" said: The Banach-Tarski theorem shows that there are pretty general classes of sets which behave unintuitively.",
"On the other hand, if you'd restrict y... |
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