title list | over_18 list | post_content stringlengths 0 9.37k ⌀ | C1 list | C2 list | C3 list |
|---|---|---|---|---|---|
[
"Do any non-human animals use other animals to do their work?"
] | [
false
] | Are there examples of animals domesticating other animals or at least using the work of another animal to their advantage? | [
"there are ",
"ants that enslave other ants",
"there are also ",
"baboons that have pet dogs"
] | [
"Some types of ants are known for farming ",
"aphids",
" for their honeydew."
] | [
"Helminths",
" and other parasites might qualify."
] |
[
"What is the relation between becquerels and Sieverts?"
] | [
false
] | With the Fukushima incident, we hear of becquerels and sieverts as ways to measure, I guess, radioactivity and dosage, respectively. How should I think about the relationship between these quantities? If there are readings of 100 bq (?) in a room, and I am there for 5 minutes, is there a way to compute how many millisi... | [
"There is no direct relationship.",
"1 becquerels is 1 decay per second, irrespective of the decay type.",
"A sievert, on the other hand, is an empirical measure with a number of weighting factors, based on the type of radiation, energy level, and what tissue was exposed.",
"For example, alpha radiation is we... | [
"Very helpful."
] | [
"http://www.johndcook.com/blog/2011/03/18/understanding-radiation-units/"
] |
[
"How strong would a magnet have to be in order to repel another magnet on which a person is sat on?"
] | [
false
] | I have a pretty basic knowledge of magnets but as a designer i'm curious to their application in seating, so say if a person sat on top of a seat that had a magnet underneath, then beneath the seat was a magnet that was repelling it, could you create the illusion that the seat was hovering? and how could you achieve it... | [
"There's a lot of variables here. In short, the magnet would have to be strong enough to produce a force that is greater than the force of gravity*the mass to be moved. The force produced by a magnet depends on several factors and is not always easy to calculate. I did find an online calculator that can give you... | [
"Your best bet will be to buy/build an electromagnet"
] | [
"thanks for the reply, im off to look into that calculator. buts it's good to know that it is achievable."
] |
[
"Why does converting from one video format to another so often cause the sound to go out of sync?"
] | [
false
] | I presume this has something to do with the fact that sound is more a continuous stream and video is made of frames, but why is this problem so notoriously difficult to solve? I would think that the streams have to have a time index of some sort, so why isn't the conversion just a straight algorithmic operation? Why sh... | [
"There is nothing fundamentally difficult about getting it right, just a lot of details for the programmer to keep track of. On top of that many audio/video codecs and file formats are proprietary, vaguely defined, and/or poorly documented. And to add even more confusion the program that originally created the fi... | [
"Modern media is stored in what's called a digital container. Common containers you may have seen are .mkv, .avi, .ogg or .mp4. A container is usually a flexible file format that allows all sorts of media streams to be stored within it. A container might have 1 video stream and 2 audio streams, or 2 video streams a... | [
"I was going to comment on this but that pretty much covers that I was going to say. ",
"However the hardware is also responsible. A lot of slower machines like netbooks will get out of sync when playing high resolution video because of the processing power required.",
"edit: You know ",
"r/programming",
" ... |
[
"How is entropy quantified?"
] | [
false
] | What makes something classified as more orderly than something else, and is there a way to quantify the entropy of a system? | [
"Entropy is difficult to explain because it is a fundamentally useful mathematical number that corresponds only loosely to what people intuitively think of as entropy.",
"When I think entropy, what immediately springs to mind is the density of states. Basically entropy is a measure of how many possible configurat... | [
"It's actually quite beautiful. It's the number of possible states a system of a fixed energy can have (actually, the logarithm of that number).",
"The more states that a system can be in, but still be indistinguishable as far as energy goes, the higher the entropy."
] | [
"If we take the macroscopic state as the number of heads and tails, then a 2-2 H-T distribution could be the result of:",
"While a 4-0 H-T distribution would be the result of ",
"So a 2-2 H-T distribution can be the result of any one of 6 microstates, while a 4-0 H-T distribution can only be the result of 1 mic... |
[
"Are there any examples of natural hybridization, or any possibilities of this occurring in nature?"
] | [
false
] | Have there ever been any naturally found examples of hybridization in wild animals? I know hybrid animals cannot breed and so would be rare one offs effectively but have we ever found an example of hybrid animals existing naturally rather than being the result of captive breeding? | [
"Yes, it's actually a pretty standard avenue toward speciation, aka the recognition of a new species ",
"https://en.wikipedia.org/wiki/Hybrid_speciation",
"It's more common in plants but it happens in animals as well. Hybrid animals actually can sometimes reproduce (that's how they can become a new species, aft... | [
"Completely normal. Even hybrid bears have been known (polar bear x grizzly). The Dingo population in Australia is suffering because they mix with feral dogs. It made the news when a 100% pure Dingo puppy (of a certain sub species) was found, he is now fathering little Dingos to help the species. Other animals also... | [
"Only female ligers are fertile, males are sterile. This is part of why we still consider lions and tigers to be different species not subspecies"
] |
[
"Plastic in the microwave, is there really any danger to it?"
] | [
false
] | null | [
"The majority of plastics can withstand microwave radiation and won't break down nor melt. If you are buying commercial products, you might be able to find \"microwave safe\" symbols on them, which I think look like three squigly lines. Essentially, if you're buying plastics that look like they were designed for st... | [
"Thanks a lot, that was quite interesting."
] | [
"I can't add anything to Sad_Scientists excellent comment but I have, out of concern for BPA, started using all glass storage ware (got a stack of nested bowls at Walmart that are thick and microwave safe). and have been quite happy with them. I eat a lot of leftovers so I use these bowls almost everyday and I at l... |
[
"How does star size affect planetary characteristics?"
] | [
false
] | I'm most interested whether the current model(s) of star/planet formation show any trends between star size and the characteristics of planets in orbit. For example, are larger stars expected to have more or fewer planets? Is there a negative or positive correlation between star and planet size? Are "Hot Jupiters" more... | [
"Hi,",
"This is an interesting question, before I get started have a look at [exoplanet.eu](",
"www.exoplanet.eu",
") which has a list of planets in a nice table format, with web plotting tools :-).",
"Also it should be noted that (almost) all of the data we have on planets is biased towards massive planets... | [
"Its a constant. In reality it probably does vary with stellar mass but we cant tell with our data"
] | [
"Thanks very much for the answer and the data link.",
"I understand the problem with the bias in observable data towards planets that are easy to detect from earth. That's why I was interested in what the current guesstimate models would indicate too. Thanks for the handy rule of thumb equation. Just for clarific... |
[
"Could desiccant packets (from food boxes etc) control humidity in a larger space, and how long would they be effective?"
] | [
false
] | So a desiccant packet can apparently keep my shoes dry in a shoebox. If I gather 100 of them and put them in a can or something, would that keep a filing cabinet full of pictures and papers dry (assuming the filing cabinet is in a residential place, not a jungle) and act as a 'humidity safeguard'? How long would it wor... | [
"It depends on the ambient conditions, the size of the desiccant particles (and therefore surface area), and any other number of conditions. Desiccants can be reused, simply by placing them in an oven until the moisture is driven off."
] | [
"We have a (no longer used) desiccant cabinet in the lab. It has roughly the interior volume of a dorm fridge and it has a lower shelf for desiccant that sits in a tray. It used to be used to keep really hygroscopic stuff moisture free, and we just had to bake the desiccant every few weeks.",
"I also use the same... | [
"So, we do have desiccant wheels in some ventilation systems. These are energy recovery ventilators designed to take moisture out, or put moisture into a space. There is an outbound and inbound air stream and the wheel rotates to adsorb then evaporate the moisture, taking it in our out of the space, depending on w... |
[
"Does There Exist A Series Smaller than the Harmonic Series that STILL Diverges?"
] | [
false
] | Is there such a thing, or is the Harmonic series the smallest series we know of that still diverges? I'm not exactly sure if I'm phrasing the question properly, in the sense that it may not be exactly clear what "a series smaller than the harmonic series" even , right? I mean, there's an argument to be made that the h... | [
"Yes, there is a way to talk about how fast a series converges or how slowly a series diverges. Let's consider only series with positive terms. So a",
", a",
", ..., a",
", ... is a positive sequence and the partial sums",
"s",
" = a",
" + ... + a",
"are positive and increasing.",
"We can compare th... | [
"The Nth term in the Harmonic Series is approximately equal to log(N) (where this is the natural log). In fact, the difference between 1+1/2+1/3+...+1/N and log(N) is pretty small and measured by the ",
"Euler-Mascheroni Constant",
".",
"But there are definitely series that diverge slower than the Harmonic Se... | [
"Yes."
] |
[
"Why does recently gained muscle mass deteriorate when there's a lack of physical activity?"
] | [
false
] | null | [
"Muscles consume large amounts of energy. Your body attempts to be as energy efficient as possible to survive for long periods without food. Therefore it rids you of unused muscle mass, which is just wasting energy."
] | [
"Your body knows, that keeping around enough ",
" is copasetic.\n",
" getting rid of \"unused\" muscles and converting the daily intake of excess energy into fat is the better long term plan for survival.",
"In return the muscles which you really ",
" will get used to carrying around more mass and adapt."
] | [
"If you have muscle already and consume tons of energy but are not really using your muscles, it is ",
" more efficient to reduce muscle mass and store excess food energy in fat."
] |
[
"Do houseplants \"die from old age\"?"
] | [
false
] | [deleted] | [
"Have you repoted your yellowing plants into fresh high quality soil at least once every year or two for the duration of you owning it?",
"I got a plant from my sister once that had been good for a long time but had been slowly becoming less and less healthy. (yellowing and thinning leaves)",
"First thing I did... | [
"This is all great advice but does not answer the scientific question at all. :("
] | [
"From what I remember, its life cycle has two stages, polyp (immobile on the seafloor) and medusa (jellyfish form), and it is able to indefinitely switch between the two, renewing its own life in the process."
] |
[
"How do we know the rate at which atomic clocks lose time?"
] | [
false
] | If they are the most accurate means of measuring time, what are they being compared to when we say they drift x seconds in y million years etc. | [
"It's very simple, you compare them to each other. Because the error is random, calibrating a group of atomic clocks to the same time and seeing them drift apart gives you an indication of the individual error rate.",
"Of course, you don't know which one of them is right, most likely all of them will have lost ti... | [
"It's not a drift, it's an uncertainty. If it was a definite and constant change in one direction it would be correctable while a random error isn't. So if they say it's x seconds in y million years that's just a more relatable way of stating the estimated uncertainty in the measurement than saying that one tick va... | [
"More specifically, if you have many atomic clocks you can use the average to get an estimate of the true time, and then from that calculate the average drift by estimating the standard deviation."
] |
[
"How is all the antimatter in the universe not destroyed by the matter?"
] | [
false
] | [deleted] | [
"There really isn't much antimatter in the known universe. Why, is a mystery. Positrons are created fairly frequently and they often annihilate with electrons. If you look for positron-electron annihilation in the sky you see it ",
"coming from the galactic center",
"."
] | [
"This has more or less been ruled out for two reasons:",
"If there were galaxies and other bodies made from antimatter, then there should be annihilation zones between these regions and matter-dominated regions. These would emit huge bursts of gamma radiation which we would be able to see from Earth. No such radi... | [
"Nothing much different from an electron scattering off something."
] |
[
"Do Superpositions in QM solve the respective Schrödinger equation?"
] | [
false
] | Can someone explain for an engineer the mathematics behind superposition I get it that <psi|psi> = 1 and that you can get the superposition with the coefficients Infront of the Eigenstates but those work because they solve the SE. How does that work with superpositions? Thanks in advance :) | [
"The Schrodinger equation is a linear differential equation, so a superposition of solutions to the Schrodinger equation is still a solution to the Schrodinger equation."
] | [
"Even when the SE is time dependent?"
] | [
"Yes, it’s still linear."
] |
[
"What is the earliest song in human history that we are not only aware of, but have some idea of how it sounded?"
] | [
false
] | I don't mean the earliest that modern society is simply aware of once existing through references or mentioning in early history, but the earliest song that we could at-least make an honest educated attempt of recreating the sound of. This could mean ancient sheet music of some form, or other means of accurately guessi... | [
"Not the earliest song, exactly, but the oldest musical piece we have a complete \"score\" for is the Seikilos Epitaph from Ancient Greece, from around the first century AD: ",
"https://en.m.wikipedia.org/wiki/Seikilos_epitaph",
"It's very short, but is actually a beautiful piece. "
] | [
"Hurrian Hymn, about 3400 years ago.\n",
"http://www.greenwych.ca/evidence.htm",
"\n",
"https://www.youtube.com/watch?v=gKN7Em9Q6qY",
"I would disagree with other theories here by saying that music existed... before homo sapiens existed. There is evidence that animals make music too, from birds to whales."
... | [
"While you live, shine",
"have no grief at all",
"life exists only for a short while",
"and time demands an end.",
"Wow. Two thousands years later, their little love song is still played and still remembered. ",
"Time, perhaps, is not the end that the lovers thought it would be."
] |
[
"Does every substance have a melting point, even crystals?"
] | [
false
] | null | [
"Crystals (at least what I imagine you mean by crystals) do eventually melt if you get them hot enough. For example, quartz melts at 1610 ",
"C and table salt (NaCl) melts at 800 ",
"C.",
"However, a lot of things will decompose before they melt, like big, bio-organic polymers. For example, paper will autoign... | [
"A simple example you can try at home is simple white sugar. Put some into a dry frying pan and put the heat on medium. It will eventually look \"wet\". This won't be water, it will be the sugar itself that is melting. Be careful though, since it will eventually burn."
] | [
"Sugar is kind of a vague term in chemistry, but assuming you mean ",
"sucrose",
", that's actually a good example of the latter category.",
"Sucrose is a disaccharide (if you look at the chemical structure, there are two distinct rings connected by an oxygen atom), and it will dissociate into its constituent... |
[
"Botanics : How many leaves does a regular tree have on average? [e.g : oak tree]."
] | [
false
] | null | [
"This would be based on age of the tree, species, health of the tree, and the season."
] | [
"But surely theres an optimum age when the tree stops growing? If so then at this age, approximately how many leaves would be on a healthy oak tree in the summer?"
] | [
"Healthy trees are not like healthy people. They rarely \"stop growing\" just because they reach a certain stature or age. A tree's whole life is a process of systemically beating out competing plants for essential nutrients, like water and sunlight. Therefore, it is in a tree's best interest to continue expanding ... |
[
"why isn't *all* of our vision as sharp as the center of our field of vision. wouldn't universal sharpness be a great adaptation?"
] | [
false
] | you could just cluster more nerves around the outside of the center point. | [
"But then you'd need a much bigger hole for all of the extra nerves to exit the eye and a lot more brain to process all of that information. Most importantly, however, there is a great advantage to pooling signals from many receptors - yes it does result in lower resolution, but it's also more sensitive to low leve... | [
"Great adaptations are only adopted if ",
" having them is a hindrance. If people without that sharp vision died, then yes, we would evolve to have it. As long as people without sharp vision everywhere stay alive and reproduce, we'll stay with that for most of the population."
] | [
"In our eyes we have two types of sensors. We have cones which are for color detection and in bright light we see better with cones. Rods, which are just light detectors, are more sensitive to detecting light. The fovea, which is in the centre of the retina, has a lot more cones than it does rods compared to the su... |
[
"Does prolonged 'slight dehydration' have any long term affects on the body?"
] | [
false
] | I know all the symptoms of dehydration, but it seems to be an acute condition easily fixed by hydration. If one we do be dehydrated for years, what would be the long term consequences? (Let's assume the person has dark yellow pee and slight dry mouth for years, maybe an occasional headache, but otherwise leads a normal... | [
"Specifics please? You have no evidence, no specific examples, no sources, and no explanations. "
] | [
"One specific consequence that comes to mind is kidney stones. Chronic dehydration increases the risk that dietary minerals will concentrate into stones."
] | [
"Yes, Chronic dehydration is actually a risk factor for a whole bunch of illnesses!",
"Water is used in the body in LOADS of different ways and in tons of biochemical pathways.",
"Just think about all the different uses in the human body there are for water: Cell life, metabolic reactions, excretion, temperatur... |
[
"I hope this isn't a dumb question. I am taking ekg classes to further my education, and one lead on the machine I am using is the \"ground\". My question is this: what is the natural \"ground\" for the electrical activity in the heart?"
] | [
false
] | Everything I have learned about closed electrical systems has come from working in an automotive shop for 15 years, and replacing or installing electrical outlets in my home. I do understand how the heart works, chemically and anatomically. I just can't seem to understand the grounding part. I have a BSN, but this was ... | [
"One thing I'd like to add is that voltage is used to measure a ",
" in potential. When you have circuits measuring change in potential caused by something like the heart, they need to compare this change to a baseline value. This value is often called ground, allowing different parts of the circuit to know how t... | [
"Thank you for your sincere answer. You did a great job explaining electricity, and putting it in terms that are easy to understand. Thank you very much for your effort. I value it."
] | [
"The ground in an EKG is used as a baseline. It is derived from a location on the body far from the heart so that it does not pick up the signals that are generated there. The EKG can then \"subtract\" the ground measurement which removes any noise in the environment giving a much cleaner reading of the hearts el... |
[
"How would Quantum Mechanics apply in complex situations?"
] | [
false
] | null | [
"Physics"
] | [
"Physics"
] | [
"Thank you for your submission! Unfortunately, your submission has been removed for the following reason(s):"
] |
[
"If dark matter is found and proven, how much would that change physics and math?"
] | [
false
] | I don't have a math background so the in depth answers will be above me, but I just wonder if a discovery like proving dark matter will have a fundamental shift in math and physics theories? | [
"Most people already work under the assumption that dark matter exists. All of cosmology just assumes it is there. The real question comes down to what is it made of, what sort of things make up dark matter. We believe it is there but currently only have guesses as to what it might be, what other properties it has ... | [
"Definitely possible. But the simplest alternative is that it's basically one thing. The properties that we can observe or deduce about it seem to be pretty uniform. Now obviously, simplest doesn't always mean much, but it's the best place to start. ",
"For instance, let's say a book falls off of your desk for no... | [
"Am I wrong, or is it possible that dark matter isn't just one thing, but actually a collection of various different things that we can't currently see or measure?"
] |
[
"Since retroviruses inject their DNA into the host's DNA, if the host's genome is sequenced, will the retrovirus DNA show up in the results?"
] | [
false
] | null | [
"Yes, in fact the human genome consists of a ",
" of retroviral related DNA sequences, as in, almost half of the genome. Since ",
"this paper is behind a paywall",
" I've put the relevant figure on ",
"imgur",
", you can see that transposable elements (which come from retroviruses either directly or are ... | [
"If the virus infects a germ cell & that germ cell leads to progeny then yes. It is one of the most convincing pieces of evidence in favor of evolution because we share the viral fingerprints of many such events with our closest relatives: ",
"https://en.wikipedia.org/wiki/Endogenous_retrovirus",
" also... i... | [
"In the case of most genome sequencing, you provide a saliva sample. Many believe it is the epithelial cells in the saliva that is used, but most companies use the white blood cells commonly found in saliva. If infected with HIV, it seems it would show up in the sequencing. Hmm. Interesting. Thanks for the reply!"
... |
[
"What are ants doing when they run into each other?"
] | [
false
] | I was just looking out my back window onto the porch and saw a line of ants running across the concrete. Every time an ant runs into another ant while traveling opposite directions they stop very briefly and then continue on. I understand the line they are following is made through pheromones and it's probably going to... | [
"I have always wondered this too; I think it has to do with a chemical exchange between them that lets the other one know that they are a part of the others colony. If I'm on the right track, Reddit, let me know."
] | [
"That's kinda what I was thinking as well. "
] | [
"\"Excuse me\"",
"\"Pardon me\""
] |
[
"What if everyone in the world got in the ocean at the same time? Is there enough coastline?"
] | [
false
] | If you could have everyone in the world hold hands, and enter the ocean, how much would the water level raise? Also us there enough coastline to pull this off? | [
"The world has a total of about 300,000 km of coastline",
"Are you ",
"sure",
"?"
] | [
"The world has a total of about 300,000 km of coastline, which is not nearly enough space for 7000,000,000 people. ",
"However, all the people of the world have a total volume of about 700 million cubic meters, which is nearly insignificant considering the 1.3 billion cubic kilometers. With a total area of 360 ... | [
"Good point."
] |
[
"If muscles can only contract, how do we expand our ribcages when taking a deep breath?"
] | [
false
] | I understand how the diaphragm can move to pull in air, but from a mechanical point of view this suction should pull one's chest in, not balloon it? I know I'm missing something... | [
"You are right, muscles only contract, and muscles do expand our ribcages with deep inspiration.",
"It's called 'bucket handle movement'. By contracting the intercostals, the ribs are pulled together and up. Due to their curvature, that means the chest gets wider laterally, increasing the overall intrathoracic ... | [
"To add to this: when the diaphragm is relaxed, it gets pulled upward into the rib cage toward the lungs. ",
"When it contracts, it pulls tight and flattens. The muscle is pulling away from the rib cage cavity, which creates negative pressure and allows air to flow in."
] | [
"Inspiration means breathing in, expiration is breathing out, and respiration is the whole process."
] |
[
"Which is the appropriate statistical test?"
] | [
false
] | null | [
"Use the chi square goodness of fit test. You'll perform it multiple times for the different potential genotypes. To look extra classy when you're done perform a Bonferroni correction to adjust for the fact that you have done multiple tests. ",
"For example you could try flipping a coin and getting 8/10 heads. If... | [
"Why is your data in ratios? If it is weight or something you can just use a t-test. ",
"If you want to compare expected vs observed results use a chi-squared goodness of fit test.",
"Is this just the weight of black sees compared to the weight of yellow? If so perform two tailed t-test. "
] | [
"It's the number of mature seeds. I think it's called kernels.\nMy aim is to find the possible genotypes of the parents, so I am comparing the ratio observed (black to yellow) with the theoretical ratio of possible genotypes of parents.\nI hope I clarified any misunderstandings, if the information I'm giving is sti... |
[
"Why do some people handle spicy foods better than others?"
] | [
false
] | null | [
"I'm a scientist that studies the proteins that your taste buds and nerves use to detect various substances that give most spices their distinctive taste. Most of these proteins are TRP-channels, and are activated by many diverse substances (",
"chili",
" for TRPV1, ",
"cloves",
", ",
"thyme",
" and ",
... | [
"I have been told (I cannot cite sources) that eating spicy food will lead to endorphins being released as the body attempts to counter the 'pain'. Over time, people who enjoy spicy food have learned to associate their favourite food with the rather pleasant feelings associated with endorphin release.",
"See also... | [
"There are proteins expressed in certain tissues that are taste receptors. These receptors, like any other protein in your body, may be slightly different than other peoples' receptors. This, because of Genetics. An example of a \"spicy\" tasting molecule would be capsaicin:",
"http://en.wikipedia.org/wiki/Capsai... |
[
"Do I have more fat cells in my abdomen, or do the ones there just get bigger faster?"
] | [
false
] | I was also wondering if the body can make more fat cells. I heard somewhere that we always have the same amount, they just get bigger and smaller depending on how much you're storing. However, if someone has liposuction and then gains weight again would theyexpand in different areas of their body, or create new fat cel... | [
"In short, both size and number.\nUsually the size of your body is not given by the size of the cells, it is given by their number. So a 100kg guy will have his cells almost the same size as a 50kg guy but in a larger number.\nWhite adipocytes (the ones that make you fat) can vary in size. The cell has a lipidic dr... | [
"So if someone weighs 300 lbs and then loses 150, the number of fat cells will stay the same but their size will get smaller?",
"Also, does this mean if someone were to weigh 150 consistently they would have less fat cells and therefore look \"leaner\" than a similarly weighed/muscled person?",
"If yes, will li... | [
"any sources for this?"
] |
[
"If you expose a baby to stressful experiences (eg music), would the child develop better coping skills, or be more prone to stress later in life?"
] | [
false
] | [deleted] | [
"Attachment theory suggests that it would make the person worse at dealing with stress. The idea is that children who feel that the world is safe, learn to deal with distress is functional/productive ways - fixing the underlying issue and seeking emotional support. However, kids who receive inconsistent or insuffic... | [
"cool question though"
] | [
"I have got exposed to heavy music.According my mother, my father used to turn the volume up of our home radio, whenever I started to cry.Then there I am stopping the crying part and within few minutes I'm dreaming according to them :) Now I am 27 and I am the most calm and collected person in such situations, amo... |
[
"What is the economic theory behind \"one price for all sizes\" regarding coffee sales."
] | [
false
] | Do customers trend towards larger sizes? Is the one price for a predicted average volume sale? It's an interesting sales tactic and I was wondering if any sales or economic research existed on the topic. | [
"When I worked in a small cafe, I asked my boss why it was worth it to brew an entire cup of coffee for only one cup. ",
"The amount of coffee grinds used for a pot of coffee, including water and energy, is significantly less than the cost that single cup is being sold for ($1.35 for a small). In fact, the cup an... | [
"To the business selling the cup of coffee, the cost of the actual cup (paper or styrofoam) is normally much higher than the contents of the cup themselves. The additional cost of brewing a pot of coffee or drawing a cup of soda is nominal.",
"Cup: $0.15\nLid: $0.03\nSoda: $0.12 \n --------------\nTota... | [
"How can it be the \"price of the smallest size for any size\"? They're all one price, so you could just as well say it's the price of the largest size for any size.",
"Edit: changed size to price."
] |
[
"If mass alters the curvature of spacetime, does charge distort spacetime or some electromagnetic analogue?"
] | [
false
] | null | [
"The source of gravity is the stress-energy tensor, which includes things like mass, momentum, pressure, etc. Charge itself does not contribute to the stress-energy per se, but the electromagnetic field does.",
"Roughly, a gravitational monopole (a point mass) has a corresponding Newtonian gravitational potential... | [
"Charge affects the curvature of the fibre bundle associated with the electromagnetic field, which is, roughly speaking, a point on a circle for every point in spacetime (the circle is called U(1) and is the gauge group of electromagnetism). This is very similar to the case of mass producing curvature in spacetime,... | [
"thanks for that. but to be more specific. I was curious about the following. gravity distorts spacetime, this is how it is able to act over large distances. while EM acts over scales much smaller, it still acts over distances.",
"Both the gravitational and the electromagnetic forces have infinite range. Even tho... |
[
"Do groups of galaxies orbit some larger attractor?"
] | [
false
] | We can tell there are billions of galaxies. From planets to dwarf galaxies, there is always the gravitational nature of things to always want to orbit something more massive. Do large clusters of galaxies also rotate forming the classic accretion disk or at least about an axis? | [
"No. ",
"Galaxy clusters",
" form the largest gravitationally bound objects. Superclusters are not gravitationally bound any more - their individual galaxy clusters fly away from each other over time."
] | [
"By the same logic a planet is just a system of atoms, which are themselves systems of smaller particles."
] | [
"Galaxy clusters form the largest gravitationally bound objects",
"Semantics maybe, but why do we call galaxies \"objects\"? Wouldnt it be more correct to call them \"systems\"?"
] |
[
"Is the universe finite or infinite."
] | [
false
] | I know the whole deal about the "observable universe" and all, but is there any evidence that beyond the observable limits there is an actual "hard" limit where nothing exists. And if not why doesn't the universe has a center, anything that is finite must have a geometrically calculable center unless it wraps around i... | [
"First, we observe that as far as we can tell, physics is the same everywhere. The universe is homogeneous and isotropic, meaning roughly \"the same everywhere you look.\" Sure there are pockets of galaxies and pockets without, but on the large scale, it's pretty uniform. But this also gives us a second concept. Be... | [
"Ths short answer is we don't know, but infinite is the baseline assumption, because if we assume it is flat (which is supported by observations to high accuracy) then (almost) all calculations work ",
" it was infinite euclidean space. Long answer as follows:",
"Eiichiro Komatsu",
" is the lead co-author of ... | [
"The links I provide are from leading cosmologists (e.g. at NASA), not \"navelgazing topologists\".",
"All that RRc provides to prove me wrong (he would thereby also prove the WMAP team at NASA and the head of Astrophysics at Oxford wrong, btw) is condescension, hubris and insults. I have never seen RRc provide a... |
[
"What would happen if one human body appeared inside another human body?"
] | [
false
] | null | [
"Thank you for your submission! Unfortunately, your submission has been removed for the following reason(s):",
"guidelines.",
"If you disagree with this decision, please send a ",
"message to the moderators."
] | [
"/r/AskScience",
" is a heavily moderated subreddit. All submissions are initially placed into a moderation queue where they are let out individually, provided they follow the submission guidelines. This process can take several hours, depending on the influx of submissions, time of day, and which mods are availa... | [
"Well it certainly took you long enough"
] |
[
"Sociology/Psychology: Motivational effects of shame?"
] | [
false
] | In arguments like the recent Dan Savage / fat people shitshow people often say "Shame isn't motivational." This is presented as dogma, but I haven't seen any of these arguments supported with more than ideology and the debater's personal experience. I feel like shame is a very powerful motivational force, albeit with s... | [
"Shame is a function of society..."
] | [
"I'm a Psychology Ph.D. student and my research focuses on the self-concept and personality. From reading William James awhile back (arguably considered the father of modern psychology), he argued that shame/guilt is a emotion brought about when one behaves in antisocial ways. Basically, James said that it is the "... | [
"In response to your conclusion, I would clarify this by saying that shame is motivational in that one does not want to feel shame (we want to avoid experiencing a negative emotional state), so we engage in behavior that minimizes the likelihood of shame occurring (i.e. we behave in socially desirable ways). ",
"... |
[
"Could I escape Earth's gravity by constantly traveling upwards at 1 m/s?"
] | [
false
] | Okay, this is a question that has been bothering me for a very long time. It doesn't seem to make intuitive sense or to fit in with what I know about physical law so I was hoping someone much smarter than myself could help me understand it. Here's the scenario: Let's say you're sitting in your own personal magic rocket... | [
"Escape speed is the speed required for a particle to escape a gravitating mass (like a planet or star) under the following assumptions:",
"The last point is most relevant to your question. When we say the escape speed of Earth is ~11 km/s, we mean that for a particle to escape Earth without any additional thrust... | [
"The concept of escape speed does not apply at all to the interior of the black hole; that is the point that I was making. If a particle is beyond the horizon, it cannot come back out, regardless of anything else. Period."
] | [
"I don't really know what you're asking. \"Minimum gravitational influence is ",
"\" doesn't make any sense. So I will just summarize what I've already explained.",
"The statement \"the escape speed of this object at its surface is ",
"\" means that a particle in free-fall can escape from this object only if ... |
[
"Is it true that day care kids are healthier later on in life because they are exposed to more illness ?"
] | [
false
] | [deleted] | [
"This is somewhat of an outdated point of view. Recent research has shown that you actually need immune stimulation at an early age in order to get your immune system going. In other words, it isn't about developing specific immunity against an individual antigen, but rather about activating the whole immune system... | [
"Actually, kids who crawl around in the dirt and get exposed to multiple pathogens have fewer allergies. Allergies and asthma are almost exclusively a first world problem. ",
"I'm on my phone so I don't have a citation, but google \"allergies third world\" and decide for yourself. "
] | [
"I encouraged Redditors to google and decide for themselves, therefore indicating that the jury is still out."
] |
[
"Do psychopaths know that they're psychopaths?"
] | [
false
] | null | [
"Some do, some don't. It depends on whether they notice how differently they react to emotional situations than others, and how they interpret it. Many atribute their behaviour to supernatural causes and think that their lack of instinctive emotional reaction is because they are the descendants of the devil, or the... | [
"There is apparently a case of a neurologist, who studied the brains of psychopaths and then found out he has the same \"brain structure\" as a psychopath, ",
"as described in this article.",
" "
] | [
"Didn't realise someone answered to this, but thanks a lot! This is some awesome insight"
] |
[
"HAARP gets a lot of attention by conspiracy theorists, who I don't believe whatsoever, but I still don't know what HAARP is. Can a qualified person explain what's actually going on?"
] | [
false
] | HAARP gets a lot of attention by conspiracy theorists, who I don't believe, because these people seem like idiots most of the time. I don't believe for one second that most of them have ANY understanding of the technology behind . It is often the blame for some ridiculous claims such as earthquakes and what not, which... | [
"Very briefly, it sends a very high-power radio signal to the ionosphere (an upper layer of the atmosphere which reflects radio waves) and then measures the reflected signal in order to study the ionosphere. You can think of it kind of like a powerful radar station. Understanding how the ionosphere varies over time... | [
"That's interesting, because public universities are invited to do research using HAARP's facilities all the time, and you can actually schedule a tour of the facility as a member of the public by contacting their office. They only tour at certain times during the year as I understand it, but they always seem to b... | [
"I think the fact that it can actually modify the ionosphere is a lot of what feeds the conspiracy theories.",
"That, and the fact that they can modulate the auroral electrojet to generate powerful VLF/ELF signals. Lots of folks with an idea that very low frequency EM radiation can be used for mind control.",
... |
[
"Why don't we launch for space from a high flying aircraft?"
] | [
false
] | [deleted] | [
"That's how SpaceShipTwo is launched. It's fine if you don't care about orbiting, just getting high up. But the energy you need to get fast enough to orbit is about 25 times the energy you need just to up and fall back down."
] | [
"Check out the answers to ",
"a very similar question",
". In short, getting into orbit requires going at very, very high speeds. Launching from a jet won't make that part any easier."
] | [
"It would be. However, you also have to account for the amount of energy required to lift the aircraft and spaceship to launch height, so you'd want to make the aircraft as small as possible. And while you're minimizing the size of the aircraft, do you ",
" need it to have independent controls? Why don't you just... |
[
"How accurate is the usual picture of the atomic nucleus of a ball/mass of protons and neutrons? What's really happening in the centre of atoms?"
] | [
false
] | null | [
"Well, a nucleus ",
" just a collection of protons and neutrons.",
"However as is usually the case with quantum systems, cartoonish depictions of them don’t accurately show their structure.",
"A nucleus is a strongly-interacting quantum many-body system, with very rich and interesting structure. But it’s not ... | [
"Nuclear charge densities, at least for spherical nuclei, look ",
"like this",
".",
"So they’re essentially uniform out to some radius, where they quickly drop to zero. This is why nuclei can be approximated in simple models to be like liquid drops.",
"The technical term used for the “fuzziness” of the surf... | [
"Would it be more correct to imagine protons and neutrons as a force distribution that increases the closer you get to the center, like a ”fuzzy ball”? ",
"Or do they have an actual ”surface” as in some point where their effect on other particles goes from 0 to 1 instantly?",
"Or do they have a ”fluffy” surface... |
[
"Ask Anything Wednesday - Biology, Chemistry, Neuroscience, Medicine, Psychology"
] | [
false
] | Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Do you have a question within these topics you weren't sure was worth submitting? Is something a bit too speculative for a typical post? No question is too big or small for AAW. In this thread you can ask any science-related question! ... | [
"I'd say the reason it seems like it might be a good analogy is because it drastically oversimplifies DNA and the other processes going on around it. Using argument by analogy is not very persuasive since the analogy is only meant to explain complex concepts in simple terms.",
"While reducing DNA to its constitue... | [
"If DNA is a code, why isn't that an argument in favor of intelligent design? How could a code have arisen naturally? Why aren't there any other codes in nature?",
"I'm an atheist, but I don't understand why this argument for intelligent design is so easily rejected by other atheists. "
] | [
"Cool: Mind is ",
" it can be easily manipulated.",
"Sad: Mind is so plastic it can be ",
"."
] |
[
"Why do bubbles in a glass or cup tend to move to the edges and stay there?"
] | [
false
] | I don't mean carbonation. When I pour a coffee or something, the bubbles are all spread out and then "migrate" to the sides of the cup, even if you slosh it around a little. | [
"Because of the surface tension of water.",
"The bubbles will tend to have a low surface area because of the surface tension. So if a bubble sticks to the sides of a cup, a part of the bubble doesn't make contact with the liquid. This is also the reason multiple bubbles stick together; to acquire less surface are... | [
"Thank you. What causes the liquid to bulge up in the middle?"
] | [
"This will only happen if the bubbles can form a group, or when your spoon is still in the liquid. For the same reason mentioned above.",
"Another reason for your bubbles to bulge up in the middle is because of stirring or right after stirring. This situation has nothing to do with tension or area. Because of the... |
[
"Is Allicin a possible cure for MRSA? Does anyone know anything about this topic?"
] | [
false
] | I have read about Allicin and it's effects on MRSA here and there but there doesn't seem to be much research out there. I'm a layman when it comes to research papers, so that's why I have come here to check with you guys. Below are some links that apply to Allicin & MRSA. Here's a Here is a . Please note this study ... | [
"Lots of things can get MRSA. I did my master's thesis on Daptomycin, which can knock out most MRSA, as can Vancomycin and some Gentamycin (I think we had a couple of strains that were Gent resistant). CA-MRSA is much easier to knock out than HA-MRSA. I also heard something about a Linezolid which might also work."... | [
"The simplified answer: It's resistant to the most nontoxic antibiotics. We can kill the bug, but we have to use more powerful antibiotics that have more serious side effects. For instance, gentamycin has a chance of causing serious hearing damage. Other drugs are toxic in other ways, and are hard for very sick peo... | [
"I don't know anything about Allicin other than it is obtained from garlic. Garlic is historically known for its antibacterial properties and work is currently going on to use the active agents as novel antimicrobials. As for a cure for MRSA? That is a strong word, is it possible for this to kill MRSA, maybe! Howev... |
[
"Why does Moderna require two 100 microgram doses while Pfizer only requires two 30 microgram dose to produce a slightly better effectiveness?"
] | [
false
] | null | [
"Each company made an educated guess as to what they thought the right size of the dose should be before widespread testing was done for this specific vaccine. They each tried to pick an effective dose size. With more testing, it might turn out the Moderna vaccine would work as well with a smaller dose. ",
"The... | [
"The mRNA is delivered inside a lipid protective package which adds significant \"bulk\" to the actual mRNA deliverable product.",
"The two companies use different proprietary packages and Moderna's package seems to be bulkier (by 70 micrograms).",
"Ref: ",
"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC543922... | [
"Your article is from before the pandemic. Do you have a source that says the vaccine dose sizes include the LNP?",
"The EMA product characteristics say:",
"One dose (0.5 mL) contains 100 micrograms of messenger RNA (mRNA) (embedded in SM-102 lipid \nnanoparticles).",
"Which can be read both ways, but sounds ... |
[
"Is chicken/lamb/beef broth a potential risk for prion disease?"
] | [
false
] | There's no chicken prion disease that I'm aware of, but seeing as we weren't aware of the cow one until 30 years ago, it seems completely plausible. Even discounting the chicken, isn't making broth a risk, since some neural matter is bound to get into the broth? | [
"Supposing some infected brain matter gets into your lamb or beef broth then it is possible that there is a risk of infection as prions are highly resistant to normal sterilization procedures like boiling (such as in your soup pot). (",
"source",
") Prion disease is caused by the induced misfolding of a normal... | [
"it is incredibly unlikely but possible; at least in cows US regulations prevent most of the potential BSE tissues from human food supplies and animal feed. That being said it's not impossible that a cow with BSE could be broken down improperly and cross contaminated. Spinal cord contamination happens from time to ... | [
"US factory butchering techniques have, over the years, adapted to pretty much keep any brain or spinal material out of the process. Even pet food processing is very careful to segregate brain/spinal material.",
"Our local rendering plant (which used to pick up dead farm animals) has closed because it became too ... |
[
"Lead contamination in Uranium dating?"
] | [
false
] | With Uranium-Lead dating zircon crystals to determine age, finding the decay rate from U235 to Pb207. I read that when the zircon crystals form trace amounts of lead can get into the crystal and that chemically the isotopes of lead 204, 206, 207, and 208 are the same so the same proportions are present as when it was f... | [
"1 can trace amounts of Pb207 be absorbed into the forming zircon crystal",
"Yes.",
"2 if it could would it be enough to give an inaccurate dating",
"If you didn't correct for it, yes, in some cases.",
"There are a couple of ways you can correct for initial radioactive lead in a zircon. The first way is sor... | [
"I've had plenty of conversations online with faceless/nameless people who doubt the veracity of geochronologic methods because the results of such invalidate a strong personal viewpoint (e.g. billion year old zircons and young earth creationists don't mix well). Within the community of people who use these methods... | [
"Thank-you. It was a bit of a mind workout reading that, but one day I hope to be more fluent (side note, impressive, list of sources at the end). Random question, have you ever had someone say that they don't trust uranium/carbon dating? Did they have any good reason not to?"
] |
[
"How do they determine the calorie count and nutritional information for foods?"
] | [
false
] | null | [
"Is this a bomb calorimeter? I've only ever worked with a DSC, so I'm just curious which type this is."
] | [
"Is this a bomb calorimeter? I've only ever worked with a DSC, so I'm just curious which type this is."
] | [
"What OP described is a bomb calorimeter. He did leave off the standardization step... we burn a known mass of a reference material (most commonly benzoic acid) to determine the heat capacity of the system."
] |
[
"What does a model of the universe with no start and no end mean for the second law of thermodynamics?"
] | [
false
] | [deleted] | [
"This is a legit theory (the \"",
"Big Crunch",
"\"), and a really intuitive idea, but recent observations indicate that it's pretty unlikely to happen. The expansion of the universe is actually accelerating, the opposite of what the Big Crunch would predict (there's a lot more technical information in the Wik... | [
"I think the OP is referring to ",
"this submission to /r/space about a cosmology without the big bang"
] | [
"I did misunderstand the question. Gave the OP a lot less credit than he deserved. It sounded more like \"since our universe has obviously been going on forever\" than \"if this theory without a big bang is correct\" to me. My bad."
] |
[
"Are these white streaks caused by cosmic rays?"
] | [
false
] | I recently launched a weather balloon and I'm looking through the footage. At high altitude I keep seeing white streaks/dots on the screen. The footage was filmed using a Raspberry Pi camera. At 34-36 seconds in on the video below, you can see an example of these flashes if you watch it in high definition. | [
"They certainly look like cosmic rays - however, noting that the balloon burst only a second or two later, I'm wondering if they might have been some very fast bits of debris. The delay between the streaks and the rest of the debris seems a bit too long for that, though."
] | [
"They occurred some considerable time before and after the balloon popped, and only appeared above a certain altitude."
] | [
"I tried finding some away from 34-36 seconds, but got bored of watching it spin rather quickly! It sounds like they're cosmic rays then - congratulations, I guess? :)"
] |
[
"askscience, I need some help"
] | [
false
] | null | [
"A de-ionized water rinse, followed by several days in rice might be able to clean off the stains behind the screen. I would recommend ",
"doing a breakdown of the device",
" rather than just rinsing it off. ",
"Make sure you do deionized water, and not distilled or tap. I've saved an old-school Archos player... | [
"Usually liquid damage to electronic devices comes from conducting electricity and shorting something out (which is why you remove the battery or power source immediately) or from corrosion. Some devices like keyboards are often safe to wash with water when disconnected and thoroughly dried before use.",
"That be... | [
"Thank you, I hadn't heard of de-ionized water. It's gonna take some motivation but I really should take the device apart"
] |
[
"How much did the age of the universe change, if at all, when the expansion of the universe was discovered to be accelerating?"
] | [
false
] | I'm assuming the age of the universe was predicted by estimating when all the matter was at a single point, and I am not exactly sure that is how it is done. But I was thinking that the discovery of an accelerating expansion would cause a huge impact on the estimation of the age of the universe over 14 billion years. | [
"If you look at the original paper from Perlmutter et al, section 6, paragraph 2, they find that the age of the universe (relative to Hubble's constant, which isn't exactly known), was 14.5 (+- 1) billion years, compared to the estimate for a flat universe which was 14.9 (+1.4-1.1) billion years, scaled by .63/H wh... | [
"Your referring to the correction factor F from the equation ",
"age = F * 1/Ho.",
"http://en.wikipedia.org/wiki/Age_of_the_universe#Cosmological_parameters"
] | [
"You can also calculate the estimated age of the Universe (+/- about 360,000 years) by measuring the temperature of the CMB. The temperature of the CMB would already have encoded in it any sort of non-constant expansion, since the temperature is inversely proportional to the scale factor of the Universe."
] |
[
"How could super heavy elements have an \"island of stability\" ?"
] | [
false
] | Wouldn't the sheer size (volume) of the element exceed the range of the strong nuclear force? Isn't this why elements of a higher number than lead decay? Also wouldn't the repelling force of the electrostatic force, according to Coulomb's law, push the protons apart and cause alpha decay? | [
"I think I can clear this up. It could more feasibly be call the island of relative stability, because these theoretical elements will still be radioactive just like every other element heavier than lead. You're right about why atoms decay, but it is theorized that nucleons (protons and neutrons) occupy \"shells\" ... | [
"OK. I get nucleons have different energy states (the cause of gamma radioactivity is the falling from a higher to a lower) but how does this affect the battle between strong nuclear force and the electromagnetic force?"
] | [
"The extent of my knowledge is that the \"magic numbers\" of nucleons constitute a relatively stable configuration that the electrostatic repulsion has to overcome for the atom to start decaying. ",
"From what I've read, it seems pretty analogous to how electrons behave in an atom. When the valence is full, this ... |
[
"What would the Earth look like now if life had never formed here? Would there be any major geological differences?"
] | [
false
] | null | [
"The main thing that comes to mind is that various erosional processes would function quite differently without land plants. Plants have important roles as both weathering and erosional agents. Plant roots are quite efficient at exploiting cracks in rocks and essentially breaking up rocks into smaller bits (i.e. we... | [
"There would also be huge changes in the composition of deep ocean sediments. Calcium carbonate and opal would be largely absent from the geologic record. The White Cliffs of Dover and the Great Bahama Bank wouldn't exist. Sediment accumulation rates in the ocean would be way lower. The sediments might look somethi... | [
"The atmosphere wouldn't be oxygenated, but reducing. Gases like methane and hydrogen sulfide would be in the atmosphere. With carbon more in the atmosphere and less in carbonates, the atmosphere would be denser, with mostly carbon dioxide and nitrogen. Since iron would exist as reduced Fe(II), it would dissolve in... |
[
"How do scientists tell each other that a hypothesis is wrong, if at all?"
] | [
false
] | It's my understanding that articles and papers are typically written and published about findings from experiments that worked. However, sometimes the experiment doesn't work and can potentially be a large waste of resources, and to my knowledge, articles and papers usually don't have these kinds of things as their sub... | [
"They usually publish those results, too.",
"The abstracts tend to look something like:",
"\"We studied an interesting thing to determine if stuff we'd like to be true about it was true....After careful analysis, we're pretty sure that stuff isn't true. You might try looking for this other stuff that could be t... | [
"Instead of publishing negative results it is far more likely that someone will show a hypothesis to be wrong in theory. Science is to a large part done on paper before it ever makes it to a laboratory. "
] | [
"I would expect this to depend heavily on the field of study however. "
] |
[
"Can liquid oxygen (LOX) be used alone as rocket fuel?"
] | [
false
] | null | [
"No, to burn something you need a fuel and an oxydizer. You could also use products that react spontaneously with itself (hydrazine, hydrogen peroxyde, ...). Oxygen alone doesn't release any energy."
] | [
"No, oxygen is not really interesting for nuclear reactions.",
"The general idea for making rocket fuel in the Moon is to mine water in the north or south pole and split it into oxygen and hydrogen."
] | [
"It might be possible in theory but running hot oxygen gas into a rocket engine is incredibly difficult without destroying it. Oxygen will burn the metals."
] |
[
"Is consciousness independent or dependent on sensory input?"
] | [
false
] | Does our sensory input feed into consciousness (independent), or is consciousness a product of sensory input (dependent)? | [
"Consciousness evolved as a way to improve an animals chances of surviving their environment. To have a properly working mind your senses have to be stimulated from birth. We've seen what it looks like when a child has been deprived of sensory imput. locked away unloved, untouched, and unable to interact with the... | [
"Can you link some of those studies on babies who were deprived of stimulation?"
] | [
"This is like a round about way of asking \"does free will exist?\". Personally I would assume that the input is fed into the consciousness, because let's say you see two boxes, the sensory input has been fed to your brain that the boxes are there, but your consciousness must determine whether or not you open one, ... |
[
"Scientific basis for thinking that old stuff was better? Ex: every generation seems to think snl was best when they grew up with it. Is there an \"old stuff was better\" syndrome or something?"
] | [
false
] | I think it has something to do with just remembering the good and not the bad, making music etc. from earlier times seem better than what we have now. Is there a scientific explanation and name for this? | [
"Your brain has all these little rules which enable you to make complex decisions quickly. These produce cognitive distortions, which tend to make people overgeneralize or be dichotomous in their thinking. This means that they tend to take a few instances of an event, and give it more weight than it realistically s... | [
"Hi all,",
"Incidentally I happen to be a researcher who specializes in this exact topic (small world isn't it). I otherwise never post on reddit, especially ask science because I generally find it sort of intimidating, so forgive me if I make some rookie mistake here. ",
"As someone else in the thread helpfu... | [
"It is why I think things like logical fallacies and cognitive biases should be taught in school because it is extremely important that people recognise the negative effects of these \"factory settings\". Reading the wikipedia page on both concepts illuminates you as to how flawed our brains really are. It is scary... |
[
"How do human postures work? Why is it so difficult to consciously correct a bad posture ?"
] | [
false
] | What is the science behind posture correction? Is it possible to successfully correct one's posture? I came across some "exercises" for correcting posture. Do they really help? Is it possible to manipulate muscle strength and flexibility? If so, how does it work? EDIT:Sorry. I meant why is it so difficult to to be cons... | [
"I'm going to chime in although reddit hates chiropractors.\nTL:DR - Yes postural correction is possible but it takes a change in your daily lifestyle to be effective and long term. Don't sit.",
"Posture is something that is created through habit. Good posture is referred to as \"neutral spine\" with a cervical ... | [
"Muscles are weak in a shortened and lengthened position. The greater amount of sacromeres in series allows more contraction, until you venture to a point where neurologically you have limited function. Posture is adaptation, your body gets stronger in positions it spends more time in. This is not bad posture as ... | [
"Muscles are weak in a shortened and lengthened position. The greater amount of sacromeres in series allows more contraction, until you venture to a point where neurologically you have limited function. Posture is adaptation, your body gets stronger in positions it spends more time in. This is not bad posture as ... |
[
"Why can we not always remember everything immediately, or off the top of our head?"
] | [
false
] | What is the reasoning behind some pieces of information taking longer to recall (or needing an associated piece of information to help recall) than others, regardless of whether they are committed to long term memory or short term memory? | [
"Arguments stemming from the information-capacity of the brain have been out of favor for quite a while. The information capacity is so large that it's not really clear that it ",
" be reasonable to expect it to have the capacity to store everything.",
"That said, models of more distributed memory function so u... | [
"Think about how it would work out if your computer saved every file, web page, video, application, and keystroke ever entered, opened, or utilized, ",
" than those that you deem important enough to save.",
"Like that, but with your brain. ",
"The human brain has a finite (though impressive) capacity, so it o... | [
"The process of memory formation, as some have already stated, has to do with the strengthening of connections between neurons, or long-term potentiation (LTP.) Different molecular cascades have to occur to activate genes which create proteins, such as neurotransmitter receptors or cross-synaptic bridges, which ope... |
[
"Why did Chernobyl's control rods have graphite on the tips?"
] | [
false
] | null | [
"Hello,",
"Some good answers ",
"here",
" and ",
"here",
".",
"Best."
] | [
"The disaster occurred because of a cascade of slightly wrong things which all ended up being wrong in the right way to create a big reactivity excursion.",
"There were design flaws, like the positive void coefficient and the effects of the graphite tips of the control rods. There was also human error, like opera... | [
"The disaster occurred because of a cascade of slightly wrong things which all ended up being wrong in the right way to create a big reactivity excursion.",
"There were design flaws, like the positive void coefficient and the effects of the graphite tips of the control rods. There was also human error, like opera... |
[
"Are dry ice \"snow flakes\" possible and what shapes would they be?"
] | [
false
] | For instance on a planet with a mostly CO2 atmosphere and a mean temperature around the -56.4°C freezing point of CO2. | [
"I can't see any reason why this wouldn't be possible given the right temperatures and pressures. ",
"The shape of snowflakes comes from the ",
"hexagonal structure of ice Ih",
". Hexagonal structures have one unique axis in the unit cell and 2 which are identical. This leads to a snowflake being flat - tw... | [
"Here is a page about ",
"snow on Mars",
" that describes experimental work on CO2 snow. Apparently the experiments produced cuboctahedral grains of frozen CO2."
] | [
"So, it looks like the answer is cuboctahedral miniature sleet rather than 3-D lacey snowflakes. - Cool!"
] |
[
"How do behavioral adaptations get passed on genetically?"
] | [
false
] | I think I understand how physical adaptations can be passed onto offspring through DNA, but how do behavioral adaptations become instinct, (assuming a species does not teach their offspring)? Does this happen and does science understand it? | [
"Many behavioral traits can have a genetic basis, and so are passed on to offspring the same way any other trait is. Any trait without a genetic basis (which means it has no heritability, in geneticist speak) will not be passed on to offspring without teaching. ",
"There's an entire field devoted to studying the ... | [
"So it sounds like I had the cart before the horse, so to speak. I was thinking of an animal that learns a behaviour which is advantageous to its survival, which then somehow becomes encoded in its DNA (which was what I didn't understand). It sounds like its more like a random mutation in its DNA causes a behaviour... | [
"No worries -- it actually seems crazy to me that something as complex as behavior can stem from random genetic mutations. One of the reasons I love my field :)"
] |
[
"Are there instances when an infection with one pathogen 'miraculously' cures another pathology or condition within the same patient?"
] | [
false
] | I feel as though I've heard anecdotal evidence that patient X had, for example, a pathology (acquired or intrinsic) and after becoming infected with another illness found their other malady disappeared. Any validity to this or evidenced-based studies you are aware of? | [
"Yes, malaria was used to treat terminal neurosyphilis before the advent of penicillin ('malariotherapy'). The evidence isn't great due to the time period, but it certainly did benefit many patients.",
"http://jama.jamanetwork.com/article.aspx?articleid=398731",
"It's been proposed for HIV, and Lyme disease mor... | [
"there are case reports of cancer patients who become concurrently sick with some sort of viral or bacterial infection, and if they fight it off, their cancer would go into full remission post-infection. scientists think the infection may have retrained potent components of the immune system to recognize cancer cel... | [
"C. Difficile infection. This is a bacteria with a large toxin that lives in the large intestine. The toxin is related to the tetanus toxin. If the C. Difficile gets too prominent in the gut, you will die. Treatment is with a strong antibiotic (vanco), but it often recurs. If that happens, you take a sample from a ... |
[
"Is it possible to forget?"
] | [
false
] | null | [
"I'm aware of the fact that the brain works very differently; thanks for the clarification though. My answer was meant in reference to OPs question, where they imply that the brain undergoing physical changes (what alternative is there?) makes erasing information impossible.",
"EDIT: I understand now that there m... | [
"I'm aware of the fact that the brain works very differently; thanks for the clarification though. My answer was meant in reference to OPs question, where they imply that the brain undergoing physical changes (what alternative is there?) makes erasing information impossible.",
"EDIT: I understand now that there m... | [
"More or less, yes, that is my question. I was lead to believe that information was all neatly stored within our brains in one place or another. If this was the case, and our brains did not receive any trauma or large shock that would change this information, why ever would we forget it? Do we as humans \"overwrite... |
[
"Why Am I Not Getting Cauliflower or Broccoli Heads?"
] | [
false
] | null | [
"Thank you for your submission! Unfortunately, your submission has been removed for the following reason(s):",
"/r/AskScience",
"For more information regarding this and similar issues, please see our ",
"guidelines.",
"If you disagree with this decision, please send a ",
"message to the moderators."
] | [
"Ok, thank you."
] | [
"You might want to try ",
"/r/gardening",
" or other garden related subreddits. "
] |
[
"When we rip paper, are we breaking covalent bonds or just hydrogen bonding between molecules?"
] | [
false
] | Other examples would be cutting plastic with scissors, snapping a strand of hair, or smashing a rock. A carbon-oxygen bond (C=O) requires 745 kJ/mol to break the bonds. An AK47 bullet can impart 2kJ, and a human punch weighs in at a measly 100 joules. So when you tear, rip, punch, or shoot something, are you actually b... | [
"The forces that hold together the fibers in the paper are van der Waals forces (forces of attraction and repulsion between molecules, AKA friction). So you're rubbing fibers against each other and possibly breaking a few that were held together by van der Waals forces, hence the force you feel when you rip it, bu... | [
"No. ",
"Breaking a bond is a chemical change, but ripping a piece of paper is physical. When you rip paper, you are tearing fibers, that latch onto each other to hold the paper together, apart but no bonds are broken. "
] | [
"Ok thank you, i kinda had that feeling but was not sure."
] |
[
"How different would modern man be if we evolved as herbivores?"
] | [
false
] | null | [
"Of course, the question is speculative, the true answer is \"we don't know.",
"However, in this case, we had a relative which may provide some insight: ",
" aka \"Nutcracker man\"",
". These guys had specialized teeth adapted to eating coarse vegetable matter, tough roots and possibly cracking hard shelled n... | [
"Gorillas are herbivores but aren't what I'd call a prey species; the two don't necessarily go hand-in-hand."
] | [
"Gorillas are herbivores but aren't what I'd call a prey species; the two don't necessarily go hand-in-hand."
] |
[
"Is nipple confusion real?"
] | [
false
] | According to some, if a newborn is given a bottle rather than breastfed, they will often prefer the bottle over the nipple, and thus not latch onto the breast. The top result on Google indicate that this is not the case - that this is only the case if the child already has trouble latching (and thus the problems were a... | [
"Even most hardcore breastfeeding advocates will admit that the idea of \"nipple confusion\" is not real.",
"However, for some infants switching back and forth can change feeding patterns. The reason being the hard false nipple of a bottle (or a pacifier for that matter) engages a feeding reflex when the roof of ... | [
"Because nipple confusion, as the name somewhat implies, is that the infant is confused going back and forth because the mechanism of action - the latch and the suckle - are different. This is juxtaposed instead with newer ideas that it is a different satiation response rather than a mechanical issue."
] | [
"How is what you wrote consistent with saying it is not real?"
] |
[
"Why do nuclear power plants have those distinct concave-shaped smoke stacks?"
] | [
false
] | null | [
"Those are cooling towers (",
"https://en.m.wikipedia.org/wiki/Cooling_tower",
"). That particular design is apparently really good for stability, air flow, and minimal material use. They aren't just for nuclear plants, I know of coal fired plants that have them as well."
] | [
"They are natural draft towers so the long term operating costs are less than a mechanical draft tower ( one that uses fans and motors). However the initial installation cost is higher with a natural draft tower. "
] | [
"The “smokestacks” are ",
"cooling towers",
" – essentially giant radiators that are used to cool clean water. A common design uses a water spray that’s directly exposed to the air, resulting in the cloud of condensation.",
"The distinctive shape is a hyperboloid. It’s stronger than a cylinder, but can still ... |
[
"Why do electric motors have maximum torque at low rpms, while combustion engines have to be at high rpms to get maximum torque?"
] | [
false
] | I know that combustion engines get their torque from piston firings, and at low rpms, there simply isn't enough firings to get any torque. Why are electric motors able to have torque at very low rpms? | [
"Not all electric motors have maximum torque at low RPM's. Some AC induction motors don't, for example. But let's assume we are talking about a permanent magnet DC motor. ",
"In a DC motor, when the armature rotates it causes a back-EMF (coils in the armature rotating in the magnetic field of the field magnets... | [
"The torque that an internal combustion engine produces at a given RPM is the result of many, many variables. First, let us not forget ",
" torque is. Torque is the ",
" force acting to rotate the crankshaft/flywheel (or wheels, when measured on a chassis dyno). So the highest torque is going to be essentially ... | [
"Also, steam engines generate maximum torque at zero RPM. "
] |
[
"Is the super-massive black hole at the center of the Milky Way spinning in the plane of the rest of our galaxy? Would this just be a coincidence, or does one or the other have ability to influence the other into matching it?"
] | [
false
] | In all the animations I've seen of the SMBH at the center of the Milky Way, it's axis of rotation always seems to be the same as that of the surrounding galaxy. Is that just an assumption we've made, or is there some evidence to back that up? And if it does hold true, then how did that happen? Is the SMBH really massiv... | [
"A black hole's spin is determined by the matter which has fallen into it (and by its initial spin, for example when a stellar core collapses to form a BH, it has some spin). Since most of the matter which has fallen in came from the plane of the galaxy, we tend to assume that the SMBH's axis of spin is roughly ali... | [
"Is the SMBH really massive enough to gravitationally pull the rest of the galaxy to rotate around it? Or as it migrated (I'm assuming that's what happened?) to the center, did the galaxy impart the rotational direction?",
"The BH is part of the galaxy, it appeared and grew as a part of normal processes that exis... | [
"It's likely that our black hole spins on the plane of our galaxy disk as most other galaxies do. Evidence is in visible polar jets coming from the center of some galaxies.",
"Read about polar jets here:",
"http://en.wikipedia.org/wiki/Polar_jet"
] |
[
"In a gridded ion engine, what mechanism pulls the positive ions through the plasma sheath at the rear of the engine?"
] | [
false
] | [deleted] | [
"I think you may have a bad representation on how the electrical potential looks like in an ion thruster. The whole plasma inside the chamber is at high potential with respect to the plasma outside the thruster. The screen grid (the first one) is usually either left floating (and self polarize at the floating poten... | [
"Thanks a lot. This really clears up a lot. So based on the circuit diagram, the screen grid pulls the plasma to a lower potential then once through, the ions then are accelerated by a very low potential on the accelerating grid. Then once through that, the higher potential on the decelerating grid acts upon the io... | [
"The screen grid doesn't really need to be at a lower potential. The ions can just diffuse naturally through it. Its real purpose is to control the sheath at the acceleration grid and help with ion optics. In theory you could make a thruster with only one grid.",
"The deceleration grid is optional. It helps scree... |
[
"If you had to pick the 3 most important vitamins, minerals etc. that one should take on a daily basis, which would they be?"
] | [
true
] | [deleted] | [
"It might be worth pointing out that, ",
", all vitamins are necessary, though as you say present in a balanced diet. So the correct answer might be \"all of them but none at all.\""
] | [
"Not a damn one. Eat how you're supposed to eat, that's the answer. Even if you ",
" eat how you're supposed to eat you ",
" don't need any."
] | [
"Nutrition dilettante here,",
"Three micronutrients that are 1) cheap, 2) lacking in the modern diet/lifestyle, 3) likely to be slightly benificial, 4) have a very low risk of problems/accidental overdose:",
"Magnesium. According to Wikipedia, \"Human magnesium deficiency (including conditions that show few ove... |
[
"How come our Wisdom teeth grow against the other ones?"
] | [
false
] | null | [
"tl;dr Our snouts shortened faster than our teeth were reduced during our evolution, so they ran out of room.",
"If you look at the heads of other great apes in profile, including the oldest ones closer to us than to chimps and bonobos, you'll notice that their mouths stick out much farther than ours and are stil... | [
"That goes back even deeper. ",
"This paper",
" says that a sequence of two sets of teeth erupting from the front of the mouth to the back first shows up in advanced cynodonts, but before crown mammals. They don't make it clear whether the front-to-back thing starts earlier, though...just that earlier species h... | [
"How come wisdom teeth usually start growing much later than normal teeth?"
] |
[
"Archeologist, and those who study Native Americans: Do we know of any large areas of North America that were never explored by native Americans?"
] | [
false
] | null | [
"While there are certainly areas where no archaeological remains have been found, it's nearly impossible to know if no native ever explored an area. If all they left behind is footprints and all they took with them were stories that have been lost in time...",
"One might think the best bet for unexplored terrain... | [
"The basic motivations were probably the same. You go where you can make a living, but curiosity and ambition probably paved the way for more practically motivated folk. ",
"The Thule are descended from northern coastal hunter-gatherers from what is now Siberia, who migrated towards Alaska along the Bering stra... | [
"What was the motivation for people to go so far as to Ellesmere Island?",
"Today people do so for recoverable resources, for pure exploration, etc.",
"But I would assume more ancient people wouldn't have those same motivations, and it would be more of a matter of attempting to settle in a cold wasteland?"
] |
[
"Can I catch a disease from myself?"
] | [
false
] | For example, say I eat my own feces. Will that cause problems? Whatever nasty thing I ate has already been inside me, I'm hardly introducing anything new. What if I got some other body fluid from one part of me and brought it into contact with a different part, is there any way that can cause disease? Basically, I thin... | [
"Oh that's definitely a bad idea!",
"Broadly speaking we can categorise the body into bits that are inside (across a membrane) or outside (like your GI tract which is essentially just a hole which runs through us). What you're asking is can I extract the bacterial/viral content of your feces by some method and in... | [
"Don't forget good old Staphylococcus aureus. Harmless on the skin, folds, orifices etc. But a huge problem if it gets into oxygen poor areas."
] | [
"Everyone's favourite necrotising bacterium. Top marks if you combine it with gangrene."
] |
[
"Is -1 considered a prime number?"
] | [
false
] | Alright so I know the definition of a prime numer is a number only divisible by one and itself, and that 1 isn't considered a prime number. However is -1 a prime number, as it is only divisible by 1 and itsel? | [
"In a general commutative ring (a set with multiplication and addition that are compatible, e.g., distributivity), an element ",
" is said to be prime if all of the following hold:",
"If we take our ring to be the integers (",
"), then the prime elements are the usual prime numbers and their negatives (i.e., ... | [
"-1 is not prime in the traditional sense because the definition of prime numbers is restricted to natural numbers."
] | [
"There are three answers to your question:",
"By the usual definition, primes are defined on the integers greater than 1.",
"We could define primality for negative integers. ",
"-n",
" divides ",
"m",
" whenever ",
"n",
" does, because indeed -1 divides 1 (and is called a ",
"). Two numbers ",
"... |
[
"What stops us from being able to see SUSY particles if we are able to see standard particles just fine?"
] | [
false
] | As far as my understanding goes we are completely able to see standard particles. What is stopping us from seeing SUSY particles (being that they do exist?)? Is it an equation we have yet to discover? Or am I just completely misunderstanding Supersymmetry? | [
"SUSY, if it exists in nature, is what is known as a broken symmetry. Exact SUSY would, as you probably know, give exact copies of all Standard Model (SM) particles but with spin differing by one half. We don't see this though, which means, if it exists at all, SUSY must be broken by some effect. The result is that... | [
"They are (if they exist), apart from maybe one type, unstable so they aren't just there to be found. Therefore you have to produce them and because they are heavy that is hard."
] | [
"As far as my understanding goes we are completely able to see standard particles.",
"It's not as simple as you make it sound, or else it would not have taken about 50 years from when its existence was first posited to discover the Higgs boson. In light of that, what right have we to believe it will be easy to di... |
[
"How come the moons of other planets in our solar system are all named but we just call our moon \"the moon\"?"
] | [
false
] | as the title states. always wondered this. | [
"I believe the moon is also known as \"Luna\"."
] | [
"This is a question suitable for ",
"/r/askhistorians",
" rather than ",
"/r/askscience",
"."
] | [
"so what you're saying is that we shouldn't call anything \"a moon\", we should call them \"natural satellites\" and that the only \"moon\" is \"The Moon\"."
] |
[
"Surface area to speed ratio for O'Neill Cylinder to replicate earth's gravity"
] | [
false
] | null | [
"There is no demonstrable difference between the gravity due to a massive body and the force felt by an accelerating body, this is known as the ",
"equivalence principle",
" and is actually a rather deep point that serves, in a sense, as the starting point to the general theory of relativity. (This is actually ... | [
"Thanks, Antic_hay. That seems pretty fast to me. I believe the guy in the video made the assertion that the speed of the cylinder wouldn't have to be very high. ",
"Is this then inaccurate? Is there evidence there is any nation with a program even a few decades from such a station? What other obstacles are to be... | [
"It seemed pretty fast to me too, and I wrote it at 5 o clock in the morning, so bear with me as I recheck my figures :p"
] |
[
"When will most of the visible universe disappear from our sight?"
] | [
false
] | When will the known universe disappear from our sight due to the expansion it is experiencing due to these dark energy? I know the Milky Way will still be visible | [
"All objects within the Local Supercluster will coalesce on a timescale of about a trillion years, so those will always be visible. According to the timeline ",
"here",
", it will take about 2 trillion years for the last non-Local Supercluster objects to redshift to the point that we can no longer detect them ... | [
"This is actually not true. Anything with a redshift greater than 1.5 or so is receding faster than the speed of light. We have observed objects with a redshift of ~8. Even professionals get this confused (see Appendix of my reference).",
"http://arxiv.org/abs/astro-ph/0310808"
] | [
"Thanks so much to both of you, you each get an upvote "
] |
[
"What is the difference between cosmological inflation and expansion of the universe?"
] | [
false
] | I always thought they were the same thing until I watched a documentary today which seems to suggest they are different, but doesn't give a good definition of either. | [
"There is the standard expansion of the universe from GR, but then there's some \"bonus\" superfast expansion early on in the universe called \"inflation\"."
] | [
"They're the same thing and they're different. Both involve the scale factor of the metric changing over time. But the mechanism of inflation is presumed to be different from the mechanism of expansion, because none of our models for expansion suggest that inflation should occur. Which simply means we need to add m... | [
"The main differences are twofold: first, the causes of these two phenomena are separate, and second, the effects on the universe we observe today are different. ",
"Inflation is hypothesized to have been driven by a so-called primordial inflationary field. In other words, a field that existed in the earliest sta... |
[
"If the spin of a proton is 1/2, why is it said that the combined spins of its three quarks do not add up to the proton's total spin?"
] | [
false
] | I have been trying to teach myself some of the basics of quantum mechanics and am running into the formation of the idea behind spin. I know photons and electrons can have spin, and since quarks are fermions, they carry spin in increments of . Since a proton is made up of three quarks, and the spin of a proton is 1/2, ... | [
"If the spin of a proton is 1/2, why is it said that the combined spins of its three quarks do not add up to the proton's total spin?",
"Because numerous experiments have attempted to measure the spins of individual quarks inside the proton, and all of those experiments have concluded that most of the proton's sp... | [
"We have measured the spin of a proton to be 1/2. We have measured the spins of individual quarks to be 1/2 also. This spin is intrinsic, it can’t be added to or taken away, right?",
"Yes, that's all correct.",
"Are you saying that when a quark is confined within a proton, its spin is significantly less than 1/... | [
"Just a follow up question, when you talk about a proton-bounded quark's orbital angular momentum, is this analogous to the orbital angular momentum of electrons bounded to the nucleus of an atom (and tells you if it's in the s, p, d, or f orbitals)?",
"Yep, you got it. Same basic concept, though I'm sure many o... |
[
"Why do we instinctively clutch a wounded area?"
] | [
false
] | i.e. if we are injured in a specific spot, right after the injury we'll "hold" it. | [
"it's called endogenous analgesia, basically you rub over the spot it hurts and helps to stimulate more 'touch receptors' and decrease the stimulation of the receptors of where the injury occurred. That way you don't feel the pain as much.\n Why your mommy would rub your head after you hurt it and it would feel bet... | [
"Touching our own wounds helps our bodies deal with pain as it allows our brains to better \"map out\" the part of our body the pain is coming from. The more information the brain gets about the actual location, the better it can process and effectively deal with the pain. So actually, grabbing the afflicted area w... | [
"dailymail has time and time again proven to be an extremely unreliable source."
] |
[
"Can someone explain string theory and p branes?"
] | [
false
] | The subject came up earlier, and I know nothing about either, although I know a little bit about quantum physics, and I'm curious. | [
"Disclaimer: I cannot give a super-detailed explanation. My understanding probably falls above \"read a Brian Greene book\" but below \"string theory PhD student\" and well below \"Ed Witten.\"",
"String theory, as you may or may not know, is an attempt to both create a theory of quantum gravity and to unite all ... | [
"Yes.. anything you can add would be great. I love your high-level overview/description of string theory. If you can discuss why we need extra dimensions and also how forces like gravity work in string theory, for example, that would be great."
] | [
"I added an extra paragraph on extra dimensions. That's all I have time for for now!"
] |
[
"Why are most animals organ systems so similar?"
] | [
false
] | Why are there not dozens or hundreds of completely different types of organ systems? Thanks | [
"Because we arose from common ancestors."
] | [
"Descent from common ancestors is the most straightforward explanation. ",
"However, some organ systems seen in various types of animals (such as eyes in vertebrates, insects and molluscs) do not share common descent (i.e., the common ancestor of those three groups did not possess eyes) but the advantages of ligh... | [
"For the same reason you look like your biological parents."
] |
[
"Is it possible for Jupiter to get enough mass through asteroid impacts to ignite fusion? How much more mass would it need? Is there any evidence of binary systems forming this way?"
] | [
false
] | [deleted] | [
"Jupiter has a mass of ~ 1.9 x 10",
" kg, while the total asteroid belt's mass has an upper bound of 3.2 x 10",
" kg. Jupiter is literally around one or two million times heavier and wouldn't care a bit if the whole asteroid belt fell into it.",
"Jupiter is not even close to having the necessary mass to start... | [
"It's a common false claim based on imperfect nuclear physics in the 80s. The modern calculation predicts ~80 Jupiter masses to start fusing."
] | [
"The modern calculation predicts ~80 Jupiter masses to start fusing.",
"Well, to be clear, at 80 Jupiter-masses is where starts fusing regular old hydrogen. ",
"At just 13 Jupiter-masses, though, it can start fusing deuterium (heavy hydrogen), which is what defines the boundary between giant planets and brown d... |
[
"How do we know velociraptors hunted in packs and killed large prey?"
] | [
false
] | In response to this comment: they had 5 inch claws on their hind legs with which to tear you apart. Emphasis is mine. In that thread, some suggested that teeth/claw marks could indicate that; however, couldn't this also be due to velociraptors acting as scavengers like hyenas or vultures? Please include sources if poss... | [
"It's all just hypothesis and conjecture. We only have limited evidence to the behaviors of dinosaurs, for instance certain dinosaurs may have been protective mothers as fossils have been found of both the parent and nest in close proximity.",
"We use modern day animals and compare them to these prehistoric ones.... | [
"Yeah, I'm not a paleontologist. Years of feeding the 5 year old inside me with dinosaur books, have led to this. :P",
"The wiki provides all the information I know about it. It's inconclusive. Probably the only thing you could get people to agree on is that the raptor was buried almost instantly. The missing lim... | [
"Ah, thanks for the response. By your last statement alone, it seems you have some previous knowledge. You wouldn't happen to be a paleontologist, would you?",
"Also, if you could I would appreciate any further explanation about the fighting dinosaur fossils I would appreciate it.",
"Edit: Ah, I suppose you ar... |
[
"How do you date rocks? Shouldn't every rock on Earth be 4.6 billion years old?"
] | [
false
] | null | [
"When we date a rock, we are typically actually dating a particular mineral in that rock. What the age of that mineral means depends on the mineral, the rock that hosts that mineral, and the way we are dating that mineral. ",
"Let's consider some examples. One of the most common minerals we use to date rocks are ... | [
"So the age of rock is simply when it solidifies into a rock, from magma, on the Earth's surface?",
"What about rock left behind from asteroids? Can it be differentiated from normal 'crust' (is that a term?) rock?"
] | [
"For igneous rocks, yes. ",
"For your question on asteroids, you'll have to be more specific. If you're talking about a literal piece of stone from space, then yes we can differentiate those. Most of the time they're hard to tell from just looking at them. Some of them will be magnetic (",
"iron meteorites",
... |
[
"Theoretically, if I were to cut, say, two of my fingers and position the wounds the right way, would they be able to heal and get stuck together?"
] | [
false
] | null | [
"short answer: yes",
"longer answer ",
"here"
] | [
"My father shot his middle finger off with a .45 (no, I don't know how) and since it was completely unsalvageable considering parts of it were embedded in the walls and ceiling, they ended up cutting his hand open, cutting the carpals of his index and middle finger, and tranplanting the index finger onto the middle... | [
"Yes, in fact, this is how most, if not all major surgery wounds are healed. This technique of bringing the two exposed surfaces of tissues together so that they heal naturally is called ",
". I think you might be interested also in ",
"wound healing",
".",
"What happens is that collagen, a long, fibrous pr... |
[
"What makes the best drain cleaner? Acid or Base?"
] | [
false
] | So I have a nasty clogged drain which I think warrants the big gun drain cleaner. Which one is the best a typical standard pipe? I know most commercial cleaners contain NaOH and aluminum, but I have heard low pH cleaners might be better. Is there any scientific basis to as which may be better? | [
"If you've tried some drain cleaner with little to no result your best bet is probably a snake (drain augur). ",
"Any acid-based drain cleaner you can get your hands on at the local home improvement store is likely to be dilute garbage due to the inherent safety issue of concentrated acids."
] | [
"Maybe some of the scientist type will comment on this concoction. I made a drain cleaner by pouring OxiClean (sodium percarbonate) (Na2CO3•H2O2) down a drain. The particles are heavier than water and I gave them time to settle to the bottom. I then poured Muratic acid(Hydrochloric acid)(HCL) in a container of h... | [
"It would depend on what they're trying to clean, really."
] |
[
"Does the human body spend more energy to keep itself warm in the winter (thermogenesis), or by trying to cool itself in the summer (perspiration)?"
] | [
false
] | Provided the human wears adequate clothing for both the hot and cold day, and does the same level of activity | [
"This argument was a friendly debate ",
"One shared an article which stated that they made tests on cyclists to exhaustion (on different temperatures), and the fastest ones to exhaustion were those cycling in 30°C",
"The others shot this argument down by saying \"putting activity in the argument complicates it,... | [
"This argument was a friendly debate ",
"One shared an article which stated that they made tests on cyclists to exhaustion (on different temperatures), and the fastest ones to exhaustion were those cycling in 30°C",
"The others shot this argument down by saying \"putting activity in the argument complicates it,... | [
"Perspiration is the main way in which we cool our bodies. The evaporation of sweat is a passive process that does not require energy.",
"Warming our bodies, on the other hand, involves burning stored fat and shivering.",
"Therefore the human body spends more energy to keep itself warm in the winter, rather tha... |
[
"Do two objects ever actually touch on a molecular level?"
] | [
false
] | This is kind of long, and only know enough to recognize I don't understand it at all. Can two objects actually ever 'touch' each other? When you place your hand on a table? From my basic understanding, no atom actually ever touches another atom, therefor the atoms that create [the molecular chemical compound of] the s... | [
"Everything we experience as \"touch\" is a result of the electromagnetic forces. This force shows itself in several ways: magnets, static electricity... but also less obvious phenomenon like molecular bonding. Every atom is made of a nucleus of protons and neutrons and a large, spherical area of electrons. The ele... | [
"I think this is more of a physics question than a biology question. ",
"Basically the overly simplified version I recall is imagine pushing together two like poles of a magnet, it requires a fair amount of force. Electrons are going to repel each other the closer they are together so 'touching' doesn't necessari... | [
"This might be the answer you 're looking for: ",
"Veritasium: Can we actually touch anything?",
"\nActually, this one might be better: ",
"Minutephysics: Touch"
] |
[
"why is it that accidental cheek bites and other misc damage done inside the mouth do not get infected from the massive amounts of bacteria?"
] | [
false
] | null | [
"Some of these bacteria are a part of our normal flora when in the mouth but when they get aspirated or enter your lungs can and do cause issues like pneumonia and abscesses. Also, our saliva has natural anti-microbial properties as well. "
] | [
"Some of these bacteria are a part of our normal flora when in the mouth but when they get aspirated or enter your lungs can and do cause issues like pneumonia and abscesses. Also, our saliva has natural anti-microbial properties as well. "
] | [
"Saliva and tears contain the enzyme ",
"lysozyme",
", which break the bonds between the N-acetylmuramic acid and N-acetylglucosamine (NAM and NAG) which make up the cell wall structure of many bacteria. ",
"This video",
" has a good demonstration for the overall \"pacman\" like activity of lysozyme as wel... |
[
"Suspending a balloon in thin air?"
] | [
false
] | [deleted] | [
"Sure, it's very easy - deflating helium balloons do it by themselves all the time. All you have to do is attach a weight to the balloon such that the density of the balloon and weight together equals the density of the surrounding air. At sea level, that density is about ",
"1.225 kg/m",
"."
] | [
"I do this all the time with mylar balloons. I usually use a few pennies then bits of duct tape until I've found neutral buoyancy.",
"If you try this you'll find that it sinks and rises and may even move from room to room as there temperature differentials in most houses."
] | [
"Yeah, but each time you wan't to fly it, you need to spend an hour dropping pennies into the front and rear compartments, making tiny adjustments, sliding them around, it is a huge pain."
] |
[
"Why doesn't the universe have a 1:1 matter to antimatter ratio?"
] | [
false
] | null | [
"This is one of the major open questions in fundamental physics. You might be interested to learn more at the ",
"wikipedia article",
" on this subject."
] | [
"We don't know."
] | [
"This is a great question and touches on some of the unsolved problems in today's physics. Many people think: if the big bang was truly an expansion from the universe that observed pair production, then equal amounts of antimatter and matter should have formed; further, these equal amounts should have annhilated to... |
[
"What does true reality look like?"
] | [
false
] | null | [
"What does it mean to expand your perception?"
] | [
"Well..humans are only experiencing a slither of what's out there as we are constrained by our built in sensory receptors and our brains make sense of the results in a language we can understand...but what we are perceiving is a subjective reality...by hypothetically expanding our perception I entertain the questio... | [
"Ok so this should really be posted to a philosophy sub, but here are my quick comments: on the one hand, maybe Kant was right and we cannot help but experience the world through our sensory systems and minds so we can never gain true access to the \"thing-in-itself\". This is a common view in perception / psycholo... |
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