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[
"Ask Anything Wednesday - Physics, Astronomy, Earth and Planetary Science"
] | [
false
] | Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Do you have a question within these topics you weren't sure was worth submitting? Is something a bit too speculative for a typical post? No question is too big or small for AAW. In this thread you can ask any science-related question! Things like: "What would happen if...", "How will the future...", "If all the rules for 'X' were different...", "Why does my...". Please post your question as a top-level response to this, and our team of panellists will be here to answer and discuss your questions. The other topic areas will appear in future Ask Anything Wednesdays, so if you have other questions not covered by this weeks theme please either hold on to it until those topics come around, or go and post over in our sister subreddit , where every day is Ask Anything Wednesday! Off-theme questions in this post will be removed to try and keep the thread a manageable size for both our readers and panellists. Please only answer a posted question if you are an expert in the field. . In short, this is a moderated subreddit, and responses which do not meet our quality guidelines will be removed. Remember, peer reviewed sources are always appreciated, and anecdotes are absolutely not appropriate. In general if your answer begins with 'I think', or 'I've heard', then it's not suitable for . If you would like to become a member of the AskScience panel, . Past AskAnythingWednesday posts . Ask away! | [
"In Larry Niven's book ",
" a hypothetical planetary system is explicated: a gas giant orbiting inside the Roche limit of a neutron star, such that it is unable to retain its atmosphere, which has subsequently gone into orbit around the neutron star as a torus of gas. The core of the giant planet is still there, ... | [
"We know Mars is mostly dead with a weak magnetic field. We also know it has about 1/3 the gravity of Earth.",
"Would it be possible using the asteroid belt and the Oort Cloud objects to not only increase the mass of the planet to match Earth's gravity but to also ensure that the right kind of metals were deliver... | [
"Besides the obvious point that the Moon would look a lot bigger in the sky, the ",
"tides",
" would have increased amplitude - at low tide the water level would decrease more than it already does and at high tide the water level would increase to a higher level compared to now.",
"In order for the Moon to ha... |
[
"What exactly is a flavor made up of?"
] | [
false
] | What is making something taste like it does? solved! Thanks so much for your answers guys! | [
"A large variety of chemical compounds. ",
"Esters are commonly used as flavoring.",
" Aldehydes and phenols are also important flavorants."
] | [
"It's a combination of taste receptors and olfactory receptors interacting with molecules in your food. As langfan mentioned, esters are especially aromatic and tasteful."
] | [
"Though a large number of ",
"functional groups",
" in molecules can change the way something tastes, our tongues have evolved to be particularly good at detecting chemicals that are important to our survival. These chemicals are detected by receptors on our tongues that bind with the appropriate chemical and s... |
[
"How does an ovary decide which egg to drop?"
] | [
false
] | When the body drops an egg from the ovary in anticipation of being fertilized, how is the specific egg chosen? Is there a queue of eggs waiting in a funnel-like system that switches every other month? Is it completely random? | [
"Humans aren’t meant to have litters- we are meant to have a single one to maximize our success with available resources. Whereas animals with large groups of offspring go for a “make a lot and hope some live” type strategy, the larger animals have just one or two to devote all the resources to that.",
"Evolution... | [
"They don't necessary drop in order, as if they were on a production line. Multiple eggs begin to start towards the path of \"dropping\" at a time. The egg that gets to drop is the first one to grow large enough to rupture (corpus hemorrhagicum). That rupture release hormones that revert the other candidates. "
] | [
"The number of mammary glands a species has is related to litter size. The relationship generally follows the \"one-half rule,\" which states that the average litter size is equal to half the number of mammaries. The number of mammaries also tends to put an upper limit on litter size. It's not necessarily a hard li... |
[
"Someone else asked about what would happen to Earth's orbit if the sun were to all of a sudden disappear. I have a related question?"
] | [
false
] | My intuition tells me it would take 8 minutes for the Earth's path through space to change, and someone in that thread said the same thing. This would seem to me that gravity behaves like information, i.e. like moving a long stick, and the other end doesn't feel the force until enough time has passed for that information to arrive at that point. Like the idea that information doesn't travel faster than light. Where this confuses me, is in general relativity. How does relativity explain this? Is it simply in that spacetime can't "deform" faster than light can travel? I have a basic working knowledge of general and special relativity, so feel free to dive into the physics of it, if that's what it takes to answer my question :) | [
"\"Where this confuses me, is in general relativity. How does relativity explain this? Is it simply in that spacetime can't \"deform\" faster than light can travel? \"",
"This is correct. Gravity propagates at the speed of light. (Brian Greene's The Elegant Universe)"
] | [
"The answer is actually a little more complicated as ",
"AaronHolland44",
" makes it to be.",
"It turns out that ",
". That is, the vector that tells you the gravitational force on an object always points to the ",
". That is, Earth orbits ",
", not where it was eight minutes ago.",
"But that's agains... | [
"In your magnetic example you have to think of individual particles and not whole objects.",
"A light year long stick, when pushed the other end will not react instantly, but why? Well simply when you push one end, you are really pushing atoms, the first layer of atoms move forward, which then tells the second la... |
[
"I have a heavy cold right now. How come, I can't last 5 minutes through the day without a heavy coughing attack, but sleep perfectly peaceful at night without ever getting the urge to cough or blow my nose?"
] | [
false
] | null | [
"I believe the urge to cough us actually a mental thought process, the same process as pain sensing. When you sleep as you progress through your cycles, specifically your REM cycles, you probably are just in such a deep sleep your mind doesn't receive the signal to cause the sensation of a need to cough. I could be... | [
"Usually coughing gets worse during night (not sleep). So you can feel lucky, I guess. While coughing is a ",
"reflex",
" it can be influenced by psychological factors as well. ",
"So Sweet_seduction69 is right basically. You probably think too much about your illness and don't get enough distraction."
] | [
"Maybe it's allergies. "
] |
[
"Where in Natural Selection did the Photic Sneeze Reflex come from?"
] | [
false
] | How would sneezing from looking at a bright light help a human in its survival? | [
"Just because it exists doesn't mean it was necessarily beneficial. I can't really speak to this so I'll let experts answer your question for sure. I would just like to bring up that point since it seems to be a common misconception."
] | [
"This is just a story though. It's very unlikely that we can actually know what the selective pressure was that drove the evolution of [insert random human trait here]."
] | [
"This is just a story though. It's very unlikely that we can actually know what the selective pressure was that drove the evolution of [insert random human trait here]."
] |
[
"Since a singularity is infinitely small, can 2 singularities be in the same place?"
] | [
false
] | null | [
"Singularities in general aren't infinitely small points, it's more common for them to have the structure of instants in time - this is the case for the Big Bang singularity or that beyond a black hole. In those two cases respectively the singularity is in the past of any observer and in the future of any observer ... | [
"You're too young to worry about spacetime."
] | [
"in the real world, singularities can't \"be in some place\". They are an instant in the future of some unlucky people."
] |
[
"Why is only half of my pine tree wet?"
] | [
false
] | Three different trees, and only half of the tree is wet after a couple days of rain. | [
"Obvious follow-up questions for clarification:",
"Was there a prevailing wind in the direction of the wet side?",
"Is there a heat or significant source of radiation on the dry side?",
"I don't know much about trees, but these details seem relevant if the answer isn't biological."
] | [
"Is there a correlation to the amount of direct sunlight each side of the tree gets? Also, have we ruled out sap, or some form of secretion from the tree itself?"
] | [
"No significant wind, but the dry side seems to mostly the west and south side of the trees. There are probably a dozen or so with this going on."
] |
[
"Why do atomic explosions require such specialized circumstances/equipment?"
] | [
false
] | The best example I can think of is rather mundane, so bear with me. In laymans' terms, the atomic bomb causes an explosion by "splitting the atom," right? Why doesn't something like cutting a loaf of bread, shooting a target, or swinging a wrecking ball cause the atom to release its energy? All of these things can cause divisions in materials which are made up of molecules and atoms. Is their resistance to force really that high? Is it just an inexpliccable fact of life? Again, sorry for the wording. It's late, I'm tired, and I'm also not the most intelligent individual when it comes to nuclear physics. Any and all answers are greatly appreciated! | [
"The nucleus of an atom is held together by the strong force. If you split the atom, you'll need to tinker with it.",
"If you cut bread, shoot a target, or swing a wrecking ball, you only encounter electrostatic forces. Much, much weaker than the strong force."
] | [
"As others said, you're separating atoms in those cases as opposed to actually splitting them. The atomic bomb actually causes an explosion by splitting a whole bunch of atoms though. It creates a chain reaction in which one atom is a split by a neutron, which then splits to release more neutrons which in turn caus... | [
"The way this works is with a certain isotope of Uranium. When you shoot neutrons that aren't too fast on that Uranium, it can capture a neutron, which makes the nucleus highly unstable such that it splits. The result is two lighter nuclei (like Caesium) and two or three more fast neutrons. If you manage to slow th... |
[
"On a molecular level why is inhaling Cyanide (HCN), even in small amounts, so dangerous to humans?"
] | [
false
] | At least with Carbon Monoxide it takes a lot to really do damage but Cyanide seems like one whiff is enough. | [
"Cyanide poisons by stopping cellular respiration - specifically, by inhibiting ",
"cytochrome c oxidase",
" in the electron transport chain. It stops the cellular machinery that's responsible for generating energy with oxygen.",
"Carbon monoxide, on the other hand, binds to hemoglobin much more strongly than... | [
"This is it exactly. Cyanide is basically poison for all carbon-based life. Which is why a lot of plants have a defense where biting or crushing the plant mixes specific chemicals that generate cyanide, in order to deter feeders.",
"There are literally a handful of species of mammals capable of eating cyanide ric... | [
"It is more complicated than the story told so far. This is a super old source, but it covers this exact topic. ",
" ",
"http://mmbr.asm.org/content/40/3/652.full.pdf",
"I'm not sure if that is behind a paywall, but it is ",
" from Microbiology and Molecular Biology Reviews 1976. ",
" ",
"Here's the rel... |
[
"I'm flying from Seattle to Australia tomorrow, are there any cool experiments I can do to show that I'll be rotating roughly 90 degrees due to the latitude difference?"
] | [
false
] | I was just thinking how I'll be rotating nearly 90 degrees. If I had a gyroscope or something, would I be able to see it slowly rotate as I fly south? Any cool experiments that could be done to show this difference in latitude? | [
"Get a protractor, tape or glue a straw to the straight edge, and tie a weighed down string to the middle. When you get on the plane, look down the straw at a star that you can easily pick out from the night sky (hope you're travelling at night!) and is viewable from both hemispheres, and mark where the string han... | [
"Theoretically it's possible: but you don't have a casing that's friction-free enough to hold the gyro in, and you don't have a good enough power source to spin it. \nIf I were you, I'd get a star chart and see which constellations are only visible on either side of the planet. (assuming the cloud cover clears up e... | [
"Foucault's pendulum",
" behaves differently at different latitudes and in an opposing manner in north vs south latitudes. ",
"The underlying principle is the same as that that causes ",
" bodies of water (and air) to drain / swirl in differing directions when isolated from other larger outside sources. "
... |
[
"Spin in particle physics?"
] | [
false
] | I know that Fermions have half-integer spin and Bosons have integer spin. I can visualize a spin of 1/2, 1, etc. but what would a spin of 0 or 2 look like? I know that 1 means it looks the same after 360° of rotation, would 2 be after 720°? | [
"As you said, one way to look at spin is in terms of rotational symmetry. If you can rotate something 360 degrees and have it look the same, that is equivalent to spin-1. Something that is spin-2 has 180 degree symmetry, and something that is spin-0 is invariant under any rotation.",
"How do you visualize spin-1/... | [
"In a certain basis (which can always be chosen), the state of a spin-S particle picks up a phase factor e",
" as you rotate it through a constant axis by an angle θ radians. So if you rotate a particle by an angle 2pi, the state picks up a factor (-1)",
". So as you can see, half-integer spins pick up a minus ... | [
"Complex numbers are numbers of the form z=x+iy, where x is a real part and y is the imaginary part. We can imagine that z is a vector on an abstract plane called the ",
"Argand plane",
", where its real part is the x component and the imaginary part is y.",
"Just like you can rotate a vector in the Cartesian... |
[
"How do Scientists derive formulas and constants?"
] | [
false
] | null | [
"It depends on the equation. Some, like F=ma are basically just mathematical expressions of an experimentally observed fact. Others, like say your kinematic equations, like, v_final = v_initial + at, are just derived from the definitions of velocity and acceleration and using Calculus.",
"As for experimental co... | [
"From experiments.",
"F=ma is a definition of force, but you can observe that forces always come in pairs: If body A exerts a force X on B, then B also exerts a force X on A in the opposite direction. You can test this with thousands of different objects and mechanisms for transmitting the force until you are rea... | [
"I teach physics and the way we do it in class is collect a bunch of data from an experiment. Then we graph the variables we are interested in. Then we compare graphs from our slightly different experiments and try to figure out the meaning of the slope and y-intercept. The slope often has a physical meaning, like ... |
[
"Is brushing your teeth with toothpaste truly the only way to maintain them ?"
] | [
false
] | null | [
"Related: I've heard recently (pretty sure it was on reddit, maybe askscience even) that there was a study that actually suggested brushing your teeth ",
" tooth paste was more effective and got them cleaner.",
"Any truth in that?"
] | [
"I also heard this on ",
"/r/askscience",
" by a dentist. I believe the reasoning he gave was that toothpaste vastly improves the experience of brushing your teeth so it increases occurrence in the population."
] | [
"Weird thing, but I actually hate toothpaste. I'd much prefer to brush without it. So is this really true? "
] |
[
"Ask Science: How do we know that the gravitational constant in our galaxy, is the same in other galaxies?"
] | [
false
] | I am very new to studying the sciences so this may be a dumb question. But if galaxies are all spinning at different speeds and expanding away from us could the gravity be different in other parts of the universe. If they were different what does this actually mean? How could we even measure it? Is there any point to measuring it? Could this explain why galaxies that collide seem to interact in ways we wouldnt expect them to? | [
"Layman here.",
"Stars life cycle is dependent on their mass. Astronomers know enough about the lifecycle of stars to be confident that the stars in other galaxies are behaving the same as the ones in ours.",
"Also the evolution of the universe is shaped by gravity. You wouldn't expect the universe to be homog... | [
"WMAP is very close to isotropic. Also, we've observed galaxies on large enough scales to see that on scales greater than about 100,000 megaparsecs, the Universe is essentially smooth and uniform."
] | [
"\"Modified Newtonian Dynamics,\"",
" or \"MOND\" is the theory that attempts to explain observed discrepancies in galactic motion with the idea that we have the gravitational equations wrong. ",
"As I understand it, two major problems with MOND are:",
"In other words, it's a formula derived out of observatio... |
[
"Some plants are known for absorbing toxic chemicals from contaminated soil, and are said to be good at soil remediation. But where do those chemicals go after they're absorbed by the plant?"
] | [
false
] | For example I've seen articles that say that cattails absorb a lot of toxins from wetlands, so they have a positive impact. But when the plant dies, doesn't it just fall down in the same environment and release everything back into the soil? What is the benefit of things like this? | [
"They’re sequestered in the plants material. The stem, the leaves, whatever.",
"Unless the pollution is some kind of organic molecule that is actually used and transformed by the plant, then the pollution just sits in the plant.",
"Those plants can then be chopped down/harvested and then properly disposed of.",... | [
"I knew of a company called Phytoteck. They planted mustard plants on contaminated soil (heavy metals), harvested them when fully grown, and then trucked them away for burial/ The EPA shut them down saying they were afraid of wind blown distribution of contaminants if the plants dried out before being buried."
] | [
"Thank you, that's really interesting!"
] |
[
"What happens when your body encounters a pathogen that it has no antibody for?"
] | [
false
] | null | [
"This happens routinely and is part of the normal immune defence to a pathogen you've never seen before.",
"1) Pathogen enters the body by whichever route you prefer - let's say you stand on a thorn or something.",
"2) The pathogen triggers the innate immune system which detects highly invariant molecules which... | [
"That doesn't really happen. That said viruses and bacteria put a lot of effort into evading the immune system, both innate and adaptive but by methods other than no corresponding T cell. ",
"Have a look at viral escape (there's a review ",
"here",
") in addition to specific bacteria like TB which hide within... | [
"So interesting! Thanks"
] |
[
"A planet orbiting two suns"
] | [
false
] | is it possible for a planet to orbit 2 suns (like in star wars) and if so what would its orbit look like | [
"It's perfectly possible to have a binary star system - either with the planet orbiting one star and the other star significantly more distant, or with the two stars relatively close together and the planet orbiting the centre of mass of the system.",
"Systems like that have now ",
"been observed",
", so yes,... | [
"This",
" applet can show you what an orbit like that could look like, select the 'binary star, planet' preset."
] | [
"When two stars are part of the same solar system it is called a binary star. The center of these type of solar systems (where our sun is in ours) is actually the center of mass between the two stars which both the stars orbit around. So if there were any planets also included in the system, they would either als... |
[
"Would a dead body get sunburnt?"
] | [
false
] | I'm asking if there would be any differences between an exposed corpse and live individual. Does the body react differently to solar radiation during decomposition? Would the length of exposure produce differing results between a corpse and a living body. I know it sounds like a silly question, but while watching Psych I noticed one of the investigations found a nude dead body out in the sunlight, and it was pale despite several supposed hours of exposure. | [
"Skin turns red due to increased blood-flow as your body tries to fix the damage caused by the UV radiation. A dead body doesn't try to fix anything."
] | [
"Adding to this; there'd still be UV damage, but in the time it would take, the heat from the sun would be helping along the bacteria eating the body, and you'd probably see decomposition before anything else."
] | [
"Not only is the redness from increased blood flow to the region, but the burn itself is actually due to UV damage to non-coding RNA, which then triggers an immune response from surrounding cells.",
"So if the biochemical reactions within the cell have come to a stop, no sunburn will be present.",
"http://www.b... |
[
"Anyone Help maths-algebra? Thanks"
] | [
false
] | null | [
"Not the right sub."
] | [
"Where should I post it?"
] | [
"/r/homeworkhelp"
] |
[
"Why are there little holes in the metal prongs of power adapters?"
] | [
false
] | null | [
"The holes are to fit little bumps on the inside of the socket to prevent the prongs from slipping out. Type A & B plug types are detailed ",
"here",
". See also the description for plug type A ",
"here",
"."
] | [
"You can purchase extension cords that slide pins into those holes. They mechanically latch and you cannot remove the plug. ",
"I have a \"Husky\" brand cord with a little switch on the outlet. That engages the pin to mechanically lock the plug. They work really well, particularly when you're pulling multiple... | [
"Dude, uk have the greatest and safest plugs in the world. Until you stand on one of course. "
] |
[
"Were there feathered 4-legged dinosaurs?"
] | [
false
] | I've done some searching but I'm not sure on the terminology to search effectively. | [
"Here's a sort of family tree of dinosaurs",
"http://biology.unm.edu/ccouncil/Biology_203/Images/Phylogeny/cladogramDino.gif",
"It's not known exactly when feathers show up, but to the best of my knowledge the group including everything to the right of T. rex (and including T. rex) probably had feathers or prot... | [
"Well, it's a matter of semantics what's a \"leg\" and what's a \"feather\". ",
"A lot of dinosaurs had shaggy fur-like feathers like a modern ",
"emu",
" or ",
"cassowary",
" or ",
"kiwi",
" bird. ",
"e.g. ",
"- the therizinosaurs",
"https://upload.wikimedia.org/wikipedia/commons/7/71/No... | [
"Thanks, this actually probably best answers my question (which I asked poorly I think :P) The diagram was helpful. "
] |
[
"Can you freeze water while it is conducting electricity?"
] | [
false
] | As the title asks. If water is currently conducting electricity, can it be frozen? | [
"Water is not actually a conductor ",
" which makes the premise problematic.",
"Ions dissolved in the water can conduct electricity though and it is basically impossible to keep ions out of water so even highly distilled water still conducts (if only a little).",
"To answer your question, the freezing water w... | [
"The current would being to heat the water (due to the natural effects of nonzero resistance), and could potentially out-do your proposed freezing method."
] | [
"What if we increased the strength of the current?"
] |
[
"I'm a EE student but I just realized my love of physics, what should I do?"
] | [
false
] | [deleted] | [
"Yes it is possible. I know a few engineers who have pursued physics at the graduate level. With an electrical engineering degree you should have the mathematical background for it (PDEs and linear algebra mostly), which is the most important thing for theory. My advice would be to take a quantum mechanics class if... | [
"I went the opposite, physics undergrad into engineering grad school. both tracks are very doable because they build off similar concepts.",
"Good luck and have fun."
] | [
"I struggled with something similar while in college. Here's what I came up with, though your mileage may vary. I was studying computer science, but had a real passion for cosmology and theoretical physics, still do actually. There were two big revelations that helped me decide on sticking with CS.",
"1) I knew l... |
[
"Putting space garbage on the moon?"
] | [
false
] | null | [
"Thank you for your submission! Unfortunately, your submission has been removed for the following reason(s):",
"/r/AskScience",
"guidelines",
"If you disagree with this decision, please send a ",
"message to the moderators."
] | [
"Can you give an actual reason why? I don't see how it's a theory to be vetted or debunked. And I'm not asking for peer review. I'm asking if space junk can be sent to the moon and why or why jot? "
] | [
"Hi, feel free to send a message to modmail to have another mod review the removal:",
"https://www.reddit.com/message/compose?to=%2Fr%2Faskscience"
] |
[
"What research is being done on animals and their inbred \"instincts\"?"
] | [
false
] | null | [
"This is too broad of a question. There is tons of research done on a variety of animals and behaviors. The keyword you are looking for is \"innate\". You can do an advanced Google scholar search for whatever animal you are interested in + innate and exclude things like \"immune\" \"immunity\" and \"resistance\" si... | [
"Right, but I'm asking people to share some things that maybe people don't know about. Or maybe they do. There's no wrong answer or specific question that needs answered, I'm asking what's out there."
] | [
"In that case, I would recommend posting to our sister-sub ",
"/r/asksciencediscussion",
". We don't really do \"what are some cool facts/examples\" posts on this sub."
] |
[
"Why does Covid-19 affect your taste and smell?"
] | [
false
] | null | [
"The olfactory support cells, which surround the neurons and help them function, are susceptible to the coronavirus. It is believed that the virus causes the olfactory epithelium to lose the cilia that detect smells."
] | [
"Short answer yes. However the stratified squamous epithelium (the lining of veins) does not typically come into contact with the virus. Currently it is thought to be impossible to spread through blood. A considerable amount of cases have had cardiovascular issues, such as strokes, bruising, encephalitis (brain swe... | [
"Doesn't the virus affect the epithelium of veins all over the body too?"
] |
[
"Why do some animals have slit pupils and some round pupils (e.g. cats v. dogs)?"
] | [
false
] | Why do some animals have pupils that form slits when closed (like cats, for example, or some snakes) while other animals have pupils that stay round (like us, or dogs)? Is there a functional difference? Does it relate to the animals' origins as a primarily nocturnal or daytime species? I am working on a boring project this morning and, looking at my cat's eyes as he sat in the sun, I just started to wonder. | [
"Imaging scientist here. The answer has to do with the resolution that can be achieved through different apertures (i.e. pupils).",
"The narrower your aperture is, the higher the frequency response is in that direction. To first order, resolution is the Fourier transform of the aperture. However, it is a tradeo... | [
"Slit pupils are an adaption to multifocal lenses.",
"Because light is dispersive, a monofocal lens cannot focus all wavelengths equally. This is a problem called chromatic aberration. For many animals, it isn't much of an issue. For small animals with large eyes, and a very low f-number, it's a big problem that ... | [
"And the craziest eyes of the animal kingdom belong to the ",
"mantis shrimp",
"."
] |
[
"Is there an explanation or at least widely accepted theory behind gluten intolerance?"
] | [
false
] | I recently met a girl who up until she left for college was able to eat all the bread she wanted. However, during her first semester she became gluten intolerant. Is it genetic? or something more? I have found lots of material on it and even explanation on why the body can't process gluten in intolerant individuals. Though, I have found nothing explaining how the body gets like that or what causes it to emerge late in life. Thanks for reading! | [
"Mm no, there is a pretty well established etiology for gluten intolerance. Now whether everyone who SAYS they have it actually has it, that is another question. ",
"I would urge you to keep an open mind and not fall into the trap of assuming something is made-up simply because it has increased in prevalence. ... | [
"Hi I'm an immunology grad student and I may be able to help you with your question",
"I guess the first thing to say is that gluten intolerance still hasn't been completely figured out. Gluten intolerance is a strange occurrence because our immune system is usually pretty good at not reacting to food proteins b... | [
"What's interesting is that most individuals who express HLA-DQ2 do not develop celiac disease even though in the western diet gluten is everywhere. So there must be other factors, genetic or environmental. It's probably both. As of now it's not completely known why this \"oral tolerance\" breaks down. Some studies... |
[
"Does the Quantum Uncertainty Principle and the CPT symmetry mean that the past is also uncertain?"
] | [
false
] | Since in theory there is a CPT symmetry, would Quantum Uncertainty also hold if we reverse the arrow of time? Does the Quantum Uncertainty Principle hold for the past, or only for the future? | [
"CPT symmetry says that the laws of physics are ",
" symmetric in time. For everyday events you might as well call it symmetric. Our direction of time is given by the fact that the past had very low entropy. Some interpretations of quantum mechanics give an additional direction of time by the measurement postula... | [
"|The name \"uncertainty\" is somewhat misleading with our modern understanding of QM. ",
"To be fair it's catchier then Heisenberg's Necessary Relation Between Position Distribution And Position Evolution Which Prevents The Position Distribution And The Momentum Viewpoint From Both Being Sharply Concentrated At ... | [
"Yes-and-no. Ultimately this is a very very philosophical question regarding how you interpret the ",
" of the physics we use to describe the world. ",
"I would roughly argue, in the vaguest terms (to somewhat avoid my own sympathies on the matter), that the past is ",
" as the future is. Ie, in the several w... |
[
"What are ways to back up computers in a manual way which would be unaffected by EMP and would still allow for data recovery to a computer?"
] | [
false
] | null | [
"You could put your storage device in a Faraday cage and it would be protected from the EMP, although that's probably not the answer you wanted.",
"Optical media would be unaffected, however they do degrade over time.",
"Paper or punch cards could be used, but the amount of data would be fairly small, and they ... | [
"It depends on how long you want to keep the data. CDs and DVDs are not affected by EMPs because the bits are actually burned into a polymer substrate. And I read about some archival DVD technology a while back that would work. The only issue with CDs and DVDs is that the data will degrade after 5 to 10 years."
] | [
"Do \"pressed\" optical discs last longer than ones that are burned? "
] |
[
"Do you happen to know any good math theory books?"
] | [
false
] | I am looking for advice on good math theory books, a similar one i've read was Zero: The Biography of a Dangerous Idea by Charles Seife. I'm also interested in physics books, but any will do. Thank you reddit | [
"Do you mean \"math theory\" in a popular-science kind of way? Or real, serious, balls-to-the-wall academic stuff?",
"Because I have to warn you... Most of it is pretty damn dense.",
"EDIT: To assist us, can you give us an idea of your level of formal mathematical education? In particular, have you done any rig... | [
"i'm currently reading this: ",
"http://en.wikipedia.org/wiki/G%C3%B6del,_Escher,_Bach",
"if you like math, physics, logic, music, and anything with patterns that might have something interesting to say about the nature of the universe, give it a shot."
] | [
"There's no such thing as math theory, there is just math. If it's not math, it's nonsense."
] |
[
"Why do allergies occur only in certain parts of the body?"
] | [
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."
] | [
"Hi there, ",
"Thanks for letting me know what was causing it to not be submitted. I have resubmitted but it still doesn't seem to have been approved?"
] | [
"I think in that case, it was just missed by us. If you resubmit it again (sorry!) and let me know here, I'll try to take care of it ASAP."
] |
[
"Calcium Channels... What does \"Q\" stand for in Q-type? L=Long Lasting, R=Resistant, N=neurotranmitter, and P=Purkinje...but I can't find the meaning of Q!"
] | [
false
] | null | [
"I will attempt to answer this as I think the original nomenclature was designated \"Q\" because it fell just after \"P\" in the alphabet. As you mention, the P Type CA2+ channel was discovered because it was in high concentrations in Purkinje neurons and thusly labeled in 1989. As scientists continued to discove... | [
"I just had a chat with Andy Randall, and he confirms, it was just the next letter after P...",
"I can also say that R was chosen the same way, and has nothing to do with \"Resistant\""
] | [
"I'm pretty sure he's getting confused with the iQ cardiac current, what is now called iH."
] |
[
"If water is hardly compressible, how do sound waves propagate through it? Do they propagate faster in water?"
] | [
false
] | null | [
"They propagate much faster. The speed of sound in water is about 1500m/s, compared to 342 m/s in air."
] | [
"So since the water is hardly compressible, the movement is faster? Does this also mean they are dampened? (edit: compared to air)"
] | [
"Sound speed is given by c=sqrt(B/ρ), where B is the Bulk Modulus (inverse of compressibility ß) and ρ is density. Water is 1000x denser than air, but it's also 15000x ",
", so the overall effect is that the speed of sound in water is considerably higher than in air.",
"An easy way to think about this is that t... |
[
"Is there any way to test products meant for humans that could potentially be harmful on non-living substances?"
] | [
false
] | After reading about rats showing empathy I wondered what it meant for ethical testing. Is there anyway to test products meant for humans on non living or "unconscious" organisms? | [
"There are in-vitro tests, that test substances on tissue samples from humans that are still 'alive', in that the cells are still doing their basic functions and are dividing. You can get detailed information about the effect the substance tested has on the cells, but as you are not actually testing in a real human... | [
"For studies that look at animal behavior, like the rat empathy study, there isn't really a good way to get around using live animals. But even still there are guiding principles that scientists follow (especially if they receive federal funding), and virtually every research institution has an Animal Care and Use... | [
"Johns Hopkins School of Public Health has a Center for Alternatives to Animal Testing; ",
"CAAT's Publications Page",
" has a lot of reading material on the subject, and it looks like your best bet is ",
"this overview brief",
". The topic of the paper is the state of alternatives as of the beginning of 20... |
[
"Why is it currently less common for the earth to encounter a large comet or asteroid than it was millions of years ago?"
] | [
false
] | I was reading Astrophysics for People in a Hurry and one of the lines gave me pause "earth's occasional encounters with large comets and asteroids, a formerly common event" NDT doesn't explain why this is, simply that it was formerly a common event. I assumed that it was either the universe was expanding and now there is more room and less collisions. Or perhaps that there are now less comets and asteroids since over time they have collided and been destroyed? Or something else I didn't think of at all? Thanks! | [
"Asteroids and comets are predominantly remnants leftover from formation of the solar system. Over the billions of years that our solar system has been around, these leftover bits have mostly had an unsteady orbit which caused them to collide with the sun, or have already collided with another object in the solar s... | [
"these leftover bits have mostly had an unsteady orbit which caused them to collide with the sun, or have already collided with another object in the solar system. ",
"The most common result is getting ejected out of the solar system.",
"Anyway, most things with unstable orbits are gone now, and everything that... | [
"Objects in orbit tend to stay in the same orbit until they either collide with another object, or pass closely enough that gravity between them alters their trajectory.",
"So most of the stuff in an orbit that could collide with earth has either collided already, or been pulled into an orbit that either can't or... |
[
"How are animal toxicity studies related back to humans when different species find different things toxic?"
] | [
false
] | Let’s take raisins for example. If you were testing raisins in dogs, the LD50 would be really low compared to the LD50 in humans. How do we account for these differences? Are there animals that have consistently had similar toxicities as humans that are used (mice? pigs?)? Are compounds tested in many different species? I know they can be tested on human cell lines, but that doesn’t necessarily equate to the whole system. | [
"Even though it's true that different species may have different response to a certain toxic substance, it's something that we are aware of and can adjust for in toxicology studies. It's also a matter of which model is more suitable for each case. As a rule of thumb, the closest the animal is to us, the more reliab... | [
"This occasionally happens. It's one of the major arguments against animal testing."
] | [
"Thanks for your response. That all makes sense, I just wonder about the hypothetical situation in which both animal models are fine and humans are not, or vice versa."
] |
[
"Do \"photonic booms\" happen?"
] | [
false
] | I suppose there's no way to know for sure, but if something moves faster than the speed of light, would it create a "boom" of light like a plane does when it moves faster than sound? | [
"It is no different from light in the way that a sonic boom is just a pressure wave. "
] | [
"Hmm interesting. Is there any real difference between Cherenkov Radiation and regular Electromagnetic Radiation?"
] | [
"Hmm interesting. Is there any real difference between Cherenkov Radiation and regular Electromagnetic Radiation?"
] |
[
"How do we find the distance between the Earth and stars?"
] | [
false
] | We know Proxima Centauri is 4.2 light years away. We know Sirius is 8.6 light years away. How do we find and calculate these distances? | [
"There are several ways to calculate the distance of stars:\nParallax: for stars relatively close by we can look at their position relative to “fixed” background stars (not truly fixed but so very far away they may as well be) and wait 6 months until the earth has completed half an orbit round the sun. When that i... | [
"I saw a YouTube video the other day where they talked about another method as well. I think it had something to do with a binary system where one star ate the other and turned into a black hole. And since we knew the exact mass the star would turn into a black hole, we could determine the distance to it by analysi... | [
"You're talking about ",
"type Ia supernovae",
", I think. As you describe, they occur when one star (a white dwarf) accretes matter off a binary companion, gaining mass until it reaches a critical threshold of 1.44 solar masses. At this point the white dwarf becomes unable to support its own weight, and it sta... |
[
"Why do radio signals of the same frequency not mix, but rather, one overpowers the other?"
] | [
false
] | For clarity: I live in between the ranges of two radio broadcasts of the same frequency, often when I am listening to one, the other takes over; why wouldn't the signals always combine to form an amalgamation of both broadcasts? | [
"This is called the capture effect, and only works with FM radios. An AM radio would actually work as you imagine. ",
"The FM capture effect isn't really a natural physical phenomenon, it's an engineered design feature. It can vary depending on how the signal chain is made. When a lower level signal and a higher ... | [
"Do the FM signals interfere naturally? If they do, will the receiver chose the signal formed by constructive interference over the individual signals? "
] | [
"Interfere could mean physical E-M wave interference, audio signal interference or frequency mixing in the radio.",
"Two radio signals will superimpose in space or air, like light from two flashlights. A spatial interference pattern can exist, like light diffraction. Two radio signals can mix in a non-linear de... |
[
"How much of fire's kinetic energy is released via photons vs. thermal conduction?"
] | [
false
] | I'm trying to build a tabletop RPG in the likes of D&D and I'm making a spell, "Darkness." I'm trying to go about it a little scientifically (as scientifically as you can get with magic) and I want to state that the spell simply "deletes" photons entering a certain area, therefore making it dark. I figured that the area would be much cooler than the surrounding area since solar radiation is mostly gone, like being in the shade of a tree vs. directly under the sun, but what about fire? If I brought a torch into this area how much cooler would it get? Is the electromagnetic radiation an insignificantly small part of the heat energy that it would feel pretty much the same, or would it feel noticably cooler? | [
"Kind of a tricky question, depends on the circumstances. Conduction is practically none in this case, it's more radiation vs convection.",
"Radiation accounts for most, if not nearly all, of the heat transfer from e.g. torches and bonfires in an open environment, e.g. outdoors, because the hot flue gas escapes t... | [
"Thanks for the answer. So the heat that you feel from a campfire is nearly all radiation? Thinking about it that makes sense. Since hot air rises, all of the air heated by convection is going up into the atmosphere. So if there was a torch in this spell you wouldn't know it was there until you placed your hand di... | [
"Yes. In our normal environment, huge numbers of photons are being emitted by everything. You don't notice because just as many are generally being absorbed. If you \"delete\" those photons, everything would freeze very very quickly.",
"I read a story once where one wizard made a spell that acted like a one-way f... |
[
"How do we know what the earth's mantle and core are composed of if we haven't directly observed them?"
] | [
false
] | When I was a kid I would often page through encyclopedia books, and one of the images that really made me stop and wonder was the picture of a cross section of the earth, with core and mantle in labeled circles. Today I realized that I've never learned the answer to how we know these things, so I'm asking you guys: How are we so confident about what's underneath the earth's crust if we haven't seen it? | [
"A few ways, but most importantly - seismic waves.",
"Every time there's an earthquake those seismic waves travel through the earth and are detected by seismometers around the globe. As well as letting us work out where exactly that earthquake happened, and what kind of fault movement it was, the arrival time of... | [
"It comes up every now and then.",
"But you're right. It could be this giant piece of alien technology in the center of earth that replicates the gravitational and magnetic forces of a solid core of molten iron. "
] | [
"In that case, what kinds of data or evidence have we gathered to determine that it's whatever amount of spinning molten iron? How do we know about the composition and volume of things inside the earth?"
] |
[
"Why does outer space look black?"
] | [
false
] | null | [
"This is called ",
"Olbers' paradox",
". More or less, the universe is quite bright. But at frequencies our eyes can't see. Everything's red-shifted too much.",
"The cosmic microwave background exists in every direction we look, a remnant of the big bang."
] | [
"It appears black because except for stars there isn't enough visible light coming from space to be detected by our eyes.",
"There isn't enough visible light because only the nearest stars are close enough to be distinctly visible. You can see the plane of the milky way where the stars are dense enough to be seen... | [
"You've have to go back quite far to see an appreciable difference. Some galaxies might be brighter than others than they are now, when things were much closer together.",
"Starting around 7 billion years ago, expansion started speeding up.",
"However, we've undergone a lot of galactic mergers over time. We're ... |
[
"What were the theories about the nature of stars before we began to understand nuclear reactions?"
] | [
false
] | null | [
"Prior to understanding nuclear reactions, identifying the energy source of the sun was an issue. Probably the best attempt (late 1800s) was the ",
"Kelvin-Helmholtz mechanism",
", which proposed the energy source of the sun came from gravitational collapse. This would require that the sun be slowly shrinking i... | [
"It is worth adding that nuclear fusion was proposed as a possible thing in the world ",
". That is, it was proposed by theorists as something that might exist, and might power stars, as early as 1920. People are sometimes surprised by this, because they expect that nuclear fusion is a younger than that, in parti... | [
"Arthur Eddington was the first to theorize it I believe, at least on paper. Einstein had already proposed the connection between mass and energy in his famous equation e=mc2 back in 1905, so the fact that a small amount of mass could create a large amount of energy was already known. Eddington took another recent ... |
[
"How close could two stars be to each other?"
] | [
false
] | null | [
"If he's looking for how close stars can be ",
" colliding, then that depends strongly on the mass and radius of the stars.",
"The mass and distance between stars defines what's called the \"Roche Lobe\". If any material of a star gets beyond the Roche Lobe (say if the star expands), then it is no longer bound ... | [
"I think you may need to clarify your question perhaps? There is no limit to how close two stars can be to each other, as ",
"stellar collisions",
" do occur. So close enough to collide and merge."
] | [
"The system PSR J0737-3039A/B has two stars that orbit each other every 2.4 hours and are a bit farther from each other than the Earth is from the moon."
] |
[
"What happens to a person's system if they are given the wrong blood type?"
] | [
false
] | null | [
"Their immune system recognises it as foreign, and the blood agglutinates (clots)."
] | [
"Then the person has a lot of infarction, because the blood clots clog the arteries and veins of the body. ",
"Strokes are infarctions of the brain, heart attack of the heart, etc. you can get them in any part of your body and they're never good. ",
"Edit:",
"I should rephrase. All of those things CAUSE infa... | [
"The type of blood is named so after the markers present on the red blood cells (ie. type A blood as A markers, type B has B markers, type O has no markers and type AB has A and B markers). Each person has the antibodies to recognise the markers they ",
" present. So a type A person will have A markers and anti-B... |
[
"Why do our bodies seem to be so inefficient at absorbing water?"
] | [
false
] | When we urinate, a huge percentage of what makes up the urine is just water. Why is so much of the water we take in completely wasted? | [
"You're not just urinating your water away for no reason. Water in urine is a ",
" that carries all your water-soluble waste. Your kidney basically partitions out a portion of your blood as a dilute solution, then meticulously release and reabsorb constituents to control the level of ions, salts, other organic co... | [
"It's not wasted, actually. The water is there as a solvent for waste products. Urine production in animals is a tradeoff between using up water and dealing with very concentrated waste. Some animals excrete much more concentrated urine, especially if they're in ecological niches where water is more precious, but t... | [
"When we urinate, a huge percentage of what makes up the urine is just water. Why is so much of the water we take in completely wasted?",
"Sorry if this sounds dickish, but I laughed a little. First, your intestines are really good at absorbing water, unless you constantly have diarrhea (in which case I am sorry,... |
[
"With a tree pollen allergy, is it better to open my windows and air out my bedroom or keep them shut up for a few more weeks?"
] | [
false
] | In the Northeast, apparantly we are in for a record pollen year. My wife is allergic to tree pollen up here and is absolutely miserable. I think it would be better to air out the bedroom, open windows and let whats in here out. She thinks letting any more pollen in would kill her. Further evidence, she seems to get worse at home than outside. We took a walk in the ark yesterday and she didn't seem that bad until we came home and the nose kicked it up a notch. | [
"As a fellow allergy sufferer, keep the windows closed. \"Airing out\" will expose more pollen into the room. Instead, try vaccuming well and cleaning surfaces that come into contact with clothes that have been outside. I always take a shower when coming home to wash off the pollen that might be on my hair and skin... | [
"Everything I've read says to keep windows closed, and if you want to air out do it quickly and open all windows so the air rushes through.",
"Pollen count lessens in damp weather. So air out on days when it is raining. I believe cold temperature also makes a difference, but I can't remember right now. Hot sunny ... | [
"I have heard there are many natural remedies for spring allergies as well. The ones that I have tried and seen work best are local and totally natural honey (can be used in tea, sandwiches, etc.), and mint. I grow mint in my garden and if you eat about one or two stalks a day, the allergies almost completely disap... |
[
"How does a black hole exhibit electric charge?"
] | [
false
] | null | [
"Electric fields don't \"move\" and don't need to escape. ",
"A charge has electric field lines extending all the way to infinity. Think of them as threads connecting the charge with a point at infinity. When the charge falls into the black hole, the field lines still have one extremity \"tied\" at infinity, whil... | [
"Let's try this way: the charge is not really associated with the volume occupied by the field, so that you could cut out a chunk of it or smth.",
"The charge in a region is actually related to the surface bounding the region, in fact it is equal to the flux of the electric field through that boundary surface. Th... | [
"Thanks! That explains some things. The second part is quite illuminating (and unexpected) actually. But there are more questions as well...",
"If an electron finds itself inside of the event horizon, wouldn't the interior \"trap\" some volume of the electric field? Would that prevent it from interacting with... |
[
"How difficult is it to damage or kill microorganisms mechanically? If I strike an anvil with a hammer, do I leave a briefly sterile surface behind?"
] | [
false
] | null | [
"Simply put, no. Basically surfaces are not smooth enough to physically crush bacteria. In fact, bacteria can actually squeeze themselves into spaces that are only a fraction of their normal width. ",
"Here",
" is a video taken at a Harvard lab that was growing ",
" under the microscope in time lapse. The bac... | [
"You can kill some cells with mechanical forces, but you won't create a sterile field by doing it. ",
"In tissue culture, you'll lose thousands (##,000) of cells every time you harvest a flask, just from the mechanical stresses of pouring or pipetting the culture media containing the cells. For reference, a 175... | [
"According to the ICAL team at Montana State University you can literally stab bacteria multiple times with an Atomic Force Microscope (AFM) tip and they remain viable. (skip to pg12 \"3.3 Investigation of mechanical properties of living Salmonella\" for the stabby bit)\n",
"http://cdn.intechopen.com/pdfs/26471/I... |
[
"Is there a substance that you can taste(with your tongue) while it is in contact with your skin?"
] | [
false
] | I think I read somewhere about this substance (can't remember if it was a liquid or solid) that you can taste while touching it with your fingers. I don't know if the information is accurate as I remember it. My reason is that if it exists and is non-toxic I would have its use be part of a hypothetical new dog training method. So if you know of any such chemical/substance, just give me the name(and/or any other info) so I can research. tx | [
"Sorta. Things mixed in DMSO (dimethylsulfoxide) cross into the body very easily. The thing I've seen mixed with DMSO most often to show the taste effect is peppermint essence.",
"This effect is also useful practically. Drugs mixed with DMSO are painted onto the skin of horses as a painless way of dosing very hig... | [
"This! I read this question and nothing came to mind, but after reading your comment it reminded me that I had a stem cell treatment with an IV fluid that was preserved with DMSO.",
"It's hard to say if I 'tasted' it, but the sense of taste and smell are so closely related it might be incorrect to separate the t... | [
"DMSO has a slight as well. Get it on the skin, and you will taste it in your mouth."
] |
[
"How (un)healthy is it for one to work nightshift?"
] | [
false
] | [deleted] | [
"For all requiring citations.",
"A Directly related article: ",
"James FO, Cermakian N, Boivin DB. Circadian rhythms of melatonin, cortisol, and clock gene expression during simulated night shift work.\nSleep. 2007 Nov;30(11):1427-36.",
"Evidence of variation in blood pressure, heart rate and onset of cardiov... | [
"For all requiring citations.",
"A Directly related article: ",
"James FO, Cermakian N, Boivin DB. Circadian rhythms of melatonin, cortisol, and clock gene expression during simulated night shift work.\nSleep. 2007 Nov;30(11):1427-36.",
"Evidence of variation in blood pressure, heart rate and onset of cardiov... | [
"Working night shifts has the many negative affects on the body. It changes gene expression, protein levels including hormone levels in many organs, including the heart. The processes that happen in your body at night and during the daytime are very different. During the day you are more active, need to eat, etc, t... |
[
"How did the first polar explorers know they had reached the pole and they weren't actually off by kilometers?"
] | [
false
] | [deleted] | [
"Astronomy. They used sextants to measure the positions of the sun (expeditions were made during the summer, so stars couldn't be used). In theory, if you are standing at the exact pole, the sun should stay at the (almost) exactly the same angle with respect to the horizon (it technically moves a tiny bit up/down t... | [
"Or in the case of Robert Peary, you just claim you got there (because he had no way of really knowing) and then proceed to bully everyone into accepting your claim. ",
"http://tierneylab.blogs.nytimes.com/2009/09/07/who-was-first-at-the-north-pole/"
] | [
"Magnetic north and the north pole are not in the same spot. In fact the magnetic north pole moves around over time (it looks like it can wander around 25 miles/year). At magnetic north I ",
" the compass would try to point down."
] |
[
"Why doesn't New Year's Day coincide with the Winter Solstice?"
] | [
false
] | null | [
"This isn't a science question; more of a history of calendar question. According to ",
"wikipedia",
", it used to be March 1st (which sort of makes sense--celebrate the new year in the spring and start of a new harvest), but in 46BC a Roman emperor moved it to January to honor the two-faced roman god Janus.",... | [
"We need an ",
"/r/AskHistory",
" subreddit."
] | [
"It is the start of new year in Iran and most of central Asia at exact moment of Spring Equinox, i.e. start of spring.",
"http://en.wikipedia.org/wiki/Norouz"
] |
[
"Why is Fahrenheit used in America, even though Celsius seems to be the generally accepted measure of heat in international science? Are there certain pros/cons to each measure?"
] | [
false
] | [deleted] | [
"Anyone who goes to high school will learn Celsius. Anyone who decides to enter science will use Kelvin."
] | [
"Celsius and Fahrenheit have no real benefits or downsides in comparison, except for ease of memorization. It tends to be easier to remember that boiling is 100C rather than 212F, and that freezing is 0C rather than 32F. ",
"The Kelvin scale, however, has real mathematical advantages in terms of simplifying for... | [
"Celsius is still commonly used in the biological sciences."
] |
[
"Does Liquid Nitrogen behave as a Bactericide?"
] | [
false
] | Let's say I have a pair of jeans covered with bacteria from daily usage. If I pour Liquid Nitrogen and flash freeze them in this manner, will it kill practically all of the bacteria? Will it preserve them? Also, will the jeans be okay if I don't touch them while they're frozen and let them thaw out on its own? | [
"Freezing bacteria is mostly bacteriostatic, and as others have mentioned, is frequently the preferred method of long-term cell storage. You do typically store them in a cryo-protectant, like glycerol, as ",
" freeze-thaw cycles will start to lyse cells. This causes enough cycles of ice crystal formation to dis... | [
"Bacteria are small. The speed at which liquid nitrogen freezes things would not allow large ice crystals to form."
] | [
"According to ",
"this",
" and other guidelines I found, Storing in liquid nitrogen is a recommended method for bacteria preservation for several species."
] |
[
"Do humans host viruses that used to be deadly to us but no longer are? How do we know they used to kill us?"
] | [
false
] | Building on the notion that HIV is becoming less deadly to us over time - how do we know what used to kill us? | [
"The remains of ancient retroviruses litter our genomes, accounting for about 8% of our total genetic material, if not more. If you count other ",
"transposable elements",
", that percentage increases dramatically. Human endogenous retroviruses (ERVs) are the remains of viruses that managed to integrate into th... | [
"Human DNA certainly contains DNA from viruses that has incorporated itself into our genome, and is now perfectly harmless. These are called Endogenous retrovirus (ERV), and could account for as much as 5% of the human genome. I suppose it's highly possible that current ERV could have descended from more dangerous ... | [
"Thanks! I am not in the field and had no idea about this."
] |
[
"How do ELISA assays work?"
] | [
false
] | [deleted] | [
"E.nzyme L.inked I.mmunoS.orbent A.ssay... ELI5 version:",
"Antibodies are small molecules that can recognize and stick to different substances, very specifically.",
"In ELISA, you stick these antibodies to a plastic plate. Then you put the tested sample on the plate. If the searched substance is present, it wi... | [
"ELISA, or Enzyme-linked immunosorbent assays, work by taking advantage of the ability of antibodies to bind an antigen with both high specificity and high affinity. For this reason it is necessary to know what Antigen you are testing before ahead of time, so that monoclonal antibodies against this antigen can be ... | [
"Minor point, this is capture ELISA, or sandwich ELISA, which is a modification of traditional ELISA that is probably the most commonly used form of ELISA in biological research nowadays. "
] |
[
"Which has more gravitational pull on me... girl sitting across from me on a bus, or the nearest star?"
] | [
false
] | NINJA EDIT: I wasn't thinking of the sun... but that comparison would be interesting as well! | [
"Gravitational force is given by f = G m1 m2 / r",
" . I'll assume a mass of 90kg for you (although it is irrelevant to the answer).",
":",
"F = 6.67x10",
" x 50 x 90 / 2",
"F = 7.5x10",
" N",
":",
"F = 6.67x10",
" x 90 x 2.4x10",
" / ( 4.0x10",
" )",
"F = 9.1x10",
" N",
":",
"F = 6.67... | [
"We don't have any sense for being pulled by a force. ",
"The feeling of being pulled down by gravity is actually the feeling of compression from being pushed up by the ground while being pulled down by gravity. It goes away in free fall or orbit."
] | [
"An interesting point is that the sun's attraction being this big is counter-intuitive (to me at least); we don't feel it as we are effectively in orbit around it. "
] |
[
"Architects or engineers of reddit, mathematically, how can you tell if a structure will be stable?"
] | [
false
] | Are there a set of equations that are used to determine how much force is applied an how much force certain parts of the structure can take? | [
"Yes, there are equations used to figure out how strong a structure is. At a fundamental level, the discipline of determining how materials respond to applied force is called ",
". Continuum mechanics is a very broad discipline that takes the fundamental laws that govern the motion of bodies (e.g. Newton's Laws ... | [
"Generally every material has ratings for how much force it can take in different ways. For example, let's say you have a steel beam. You could balance the beam on a fulcrum and apply force onto both ends (trying to bend it). You could also put the beam vertically and put a weight on top of it (trying to compress i... | [
"Generally it heavily depends on who is selling it. Different manufacturing processes and material compositions can lead to huge tolerance differences. Usually when buying things like steel beams you would be provided a data sheet that an engineer could look at and determine the tolerances because you're probably o... |
[
"At what concentrations can hydrogen sulfide gas affect chrome?"
] | [
false
] | In my city, hydrogen sulfide gas has been pervasive in the air for the last month or two due to anaerobic digestion/decay of vegetation in a stagnant water channel. The smell the gas of the gas is like rotten eggs, which is a nuisance and has made a lot of people feel sick. The city released measurements, and the concentration of the gas is about 0.375 ppm on the low end and about 2.125 ppm on the high end. However, city residents have also been complaining about finding red/rust-like stuff staining their baths/showers even if they clean daily (so it's not mold or bacteria) and the chrome trim on their cars becoming oxidized or corroded. They said the timing of it coincided with the gas problem and think there's some huge public health crisis being covered up by the city. Our city's tap water system is not connected to the channel, so I thought it was just a ridiculous conspiracy theory based on confirmation bias. However, after Googling, it turns out hydrogen sulfide gas/liquid is actually corrosive to metals, though I couldn't find at what concentration. Now I'm curious: is it possible for hydrogen sulfide gas to affect chrome trim at the concentrations I mentioned above? Is it even remotely possible for it to affect pipes from the outside? | [
"Theoretically, corrosion of metal by hydrogen sulfide will occur at any concentration and the reaction will continue until equilibrium has been reached. Increasing the concentration will only increase the rate of the reaction depending on the rate law. Normally, in a closed system, the concentration of hydrogen su... | [
"Uhh, wow, okay, that's a way more concerning answer than I was expecting. Thank you. Could you further explain what you mean by \"until equilibrium has been reached?\" ",
"Is the reaction that hydrogen sulfide gas has to metals similar to how salty sea air reacts to metals? Can the two effects be combined? My ci... | [
"Well the study of equilibrium is a pretty heavy topic in chemistry, and I don't really want to get into it, so I invite you to read up on it here:",
"https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Book%3A_Chemistry_for_Allied_Health_(Soult)/08%3A_Properties_of_Solutions/8.02%3A_Chemical_Equilibri... |
[
"Instead of other animals transmitting diseases to humans.. what diseases can humans transmit to other types of animals?"
] | [
false
] | null | [
"The rôle of humans in introducing chytrid fungus through several of their activities, including direct contact, into amphibian populations is quite well documented. ",
"see, for instance: ",
"Mendez ",
", 2008, \"Survival of the amphibian chytrid fungus Batrachochytrium dendrobatidis on bare hands and gloves... | [
"The rôle",
"Got a little French there for a second. I suspect you knew this because chytrid fungus jeopardized the frog leg industry. "
] | [
"i work at a state health department and we recently had a case of person transmitting TB to his dog. Since there is no treatment for TB in dogs the animal had to be put down. :("
] |
[
"Do amputations improve the life of the body by having less material to care for?"
] | [
false
] | If you had a non functioning leg would amputation increase body health? You have full capacity of your organs but no longer have to pump as much blood and and other health maintenance. | [
"IANAD, but I have family members involved in medicine...",
"The problem with your assumption is that limbs require maintenance, so their absence would be a net gain. But limbs do provide some benefits with regards to regulating body temperature, blood pressure, etc.",
"But one thing you're missing is that men... | [
"I was curious if there was risk of clotting in a non-functional limb, and to my surprise I found ",
"many",
" ",
"references",
" showing 10% risk of DVT ",
" lower extremity amputations. DVT can lead to ",
"pulmonary embolism",
".",
"So the risks associated with the procedure may outweigh any benef... | [
"IIRC, you can have trouble regulating temperature, blood pressure, etc., if you don't have enough periphery."
] |
[
"Is there a common structure or pattern in all things?"
] | [
false
] | [deleted] | [
"No. Certain arrangements are found in multiple domains because they're energetically favorable — spheres, tetrahedra and such like. But there's no significance to that beyond the fact that the same basic principles of dynamics apply at different scales."
] | [
"I think these things all boil down to interactions with matter (i.e. each other). The spirals you described have similar forces that induce the particle in question into spiral and orbit-like patterns, because it is an energy-efficient pattern.",
"In mathematics, fractals are related to what you're looking at, a... | [
"Why is that not significant?",
"Because it doesn't ",
" anything. For example, if I dropped a bunch of satsumas on the floor and saw that they bounced a bit, then dropped a bunch of kittens on the floor and saw that they didn't, I might be tempted to imagine some relationship between satsuma-bounciness and kit... |
[
"What is the neurochemical system involved with awareness or presence of mind?"
] | [
false
] | There's a neurochemical pathway involved with dopamine for the reward system, etc. But I haven't found any research involving physical manifestation of the pathway for mindfulness, etc. Which might provide information about how to exercise that pathway. | [
"You cannot think of the brain as a sack of neurochemicals and cells. It’s an extremely complex interconnected system that happens to have specific chemicals that affects some circuits more than others and can thus be used therapeutically. ",
"The default mode network, which is the one most clearly affected by mi... | [
"I see. That makes sense. So would there be some electrical patterns or something that would give a clue as to how you can alter the state of mind to promote self awareness, apart from maybe just practice or repetition? I write it down on my to do list with everything else, but I don't check that often enough"
] | [
"AFAIK this has only been observed recently with FMRI studies. But I understand that some attention patterns can be deduced from EEG measurements and the suppression if alpha waves. But ",
"the jury is still out on that one."
] |
[
"Why are some materials more hydrophobic than others?"
] | [
false
] | null | [
"Hydrophobicity depends on a variety of factors but the most often cited one is polarity. The basic principle is \"like dissolves like\" - polar solvents dissolve polar solutes and vice versa. To focus on the reason why, it's instructive to use water as the solvent and think about the solvations in thermodynamic te... | [
"Do the energy exercise and you will see. To help you, you should note that van der Waals interactions are inherently less stabilizing than dipole-dipole interactions, which are slightly less stabilizing than hydrogen bonds. To understand why, you must ask yourself how van der Waals interactions arise. They arise b... | [
"Why do non polar substances dissolve with each other? ",
"Why do polar substances dissolve with each other? I gather that polar substances roughly align their dipoles with each other, but what makes the interaction between, say, for H2O and NaCl, the hydrogen bonds between oxygen and hydrogen of different molecu... |
[
"Is there a term that describes the psychological phenomenon of one person in a group of friends being established as the constant butt end of jokes?"
] | [
false
] | [deleted] | [
"\"The Omega Wolf is the male or female at the bottom of the hierarchy. The omega Wolf is usually the last to feed at the site of a pack kill. The omega seems to be the scapegoat for the other Wolves and generally slinks and submits at the least act of aggression by others. When the alpha is in a particularly grouc... | [
"That would be a sociological phenomenon, not a psychological one."
] | [
"Social stratification",
" The animal equalivent is ",
"Dominance hierarchy",
".",
"I know there had been a lot of study in dominance in primates, they make some very interesting reading.",
"example"
] |
[
"How possible is it for a company with minimal polymer experience to start making useful polyurethanes?"
] | [
false
] | I work for a small ink company, and my boss has decided that we should start making our own resins (mostly the polyurethanes) since we can't find one with the correct properties. We have no polymer chemists on staff (or any PhDs, for that matter), but a few formulators. Is there any likelihood of success, and if people have any experience, how expensive would this likely be? We have very minimal equipment (although we do have a fumehood). | [
"This does not sound like a good idea, especially considering the lack of experienced personnel and equipment. First, you would need to determine the desired chemical structure of the polyurethane that you're interested in (or more probably, a variety of similar structures). Once you successfully devise a series ... | [
"I am a Polymer Chemist and I can tell you that your company will without doubt stumble badly. You cannot just willy nilly these reactions. Even if you succeed in making something useful or your desired PU you would still have to figure out how to sustain it and reproduce it. None of this can be possible without un... | [
"At first, let my clarify a few things. As far as I understand, your company is specializing in making some kind of items which have PU elements. You are purchasing these 2-pack compounds, mix them and then pour into molds for curing.",
"My next assumption is that your local PU supplier is unable to deliver produ... |
[
"What element do we consume the most?"
] | [
false
] | I was thinking maybe Na because we eat a lot of salty foods, or maybe H because water, but I'm not sure what element meats are mostly made of. | [
" Hydrogen, by number. Oxygen, by mass.",
" The stuff we eat is primary made up of three classes of molecules, and water. Those three molecules are fats, carbohydrates, and proteins and are made primarily of carbon, hydrogen, and oxygen, with a handful of other things sprinkled in. Water, on the other hand, makes... | [
"Your answer is correct on a basis of quantity of atoms, but not on a basis of quantity of mass."
] | [
"Good call. I've added some stuff. Thanks. "
] |
[
"False discovery rates and critical values for micro array data"
] | [
false
] | Hi Ask Science, So I realize this is a more specific question than is usual queried. I am looking at a micro array data set (as a noob), and I calculated a rough estimate of the FDR. But now I don't know what to do with it. How do I use these values (unique for each gene, based on the p-value*comparisons/rank) to determine a new critical value to account for false positives? For instance, Gene 1: p = 0.028203, FDR = 1.107459 Another: P-value = 5.61424E-06, FDR = 0.252641 Also, if I am only looking (a-priori) at a subset of genes, can I calculate the FDR based on (p-value*comparisons/rank)? Do I have to recalculate the rank? THANK YOU SO MUCH. | [
"My advice would be to to walk around your building until you find a lab that deals with microarrays a lot and then make a new friend. Or if your university has a genomics core they would probably be able to help you. ",
"I know i have received plenty of help from labs that have no stake in my work but were kin... | [
"Thanks!",
"We just found something pretty neat using the advice here. We have a micro array set from a selected lines (naiive to a treatment), then a separate one with saline vs treatment. ",
"We found something pretttttttty interesting just now and are scrambling to find a lab that deals with the candidate ge... | [
"You can read the original paper ",
"here",
". I think you will get it in a few hours based on the stuff you are describing. ",
"The gist of FDR is this: for one comparison, we use a p-value. For microarray data comprised of thousands of experiments, we know some of the data will be false positives, so we set... |
[
"At what \"level\" of development do creatures become conscious and is there anything other than humans that are conscious of their existence similar to us?"
] | [
false
] | null | [
"The developent of a neocortex similar to ours. I'm not an expert on the mental possibilities of other species, but I would assume that the next in line, so to speak, would probably be a dolphin, if we count primates out. ",
"I hate to say this, and I've never thought about it until now, but there probably wont e... | [
"I never thought about that but seeing how we have done with the gift maybe its best that no one else knows. It's a little embarrassing. "
] | [
"Yeah,it is. I think about it a lot and it's probably in my best interest to stop, how I am ashamed to call myself human. To an alien audience, we probably seem horrific. "
] |
[
"Why do so many people dislike foods such as fish that have been eaten all throughout human evolution?"
] | [
false
] | Wouldn't we all have it hardwired into our DNA to like fish since it is one of the most eaten foods all throughout human history and needed for survival? | [
"In relation to fish and fish only:",
"As a pretty experienced cook I can tell you that in the case of the most fussy eaters - if you lie about what's in it, they will happily eat it. I don't recommend that, but it is proof that it's just some personal bullcrap in their heads.",
"There are some folk who genuine... | [
"I would say there's definitely a difference bw rotten fish smell and the smell/taste I would define as 'fishy'. Not all, or even most, fish smell fishy to me, but some definitely do no matter how fresh. ",
"Edit: Ok I just researched it, and apparently the traditional smell ",
" from the breakdown of trimethy... | [
"No, I mean they wont eat it if you tell them what's in it, and if you don't (or you lie) they eat it and like it.",
"You're the second type I mentioned, the people that actually dislike some ingredient because of its taste, not the people with imaginary food problems (the first type)."
] |
[
"How exactly do we perceive the color of a pixel?"
] | [
false
] | Since a pixel only emits red, green and blue: how do photons of these basic colors intermingle on the retina, making the eye perceiving wavelengths which differ from these basic colors? | [
"There are ",
"three types of cones",
", each of which has a slightly different ",
"frequency response curve",
". It's slightly more complicated because that graph is normalized, but the process works the same either way.",
"Look at that graph and pick a point in between the peaks - say, 500nm (aqua). Not... | [
"The colors we see are not a single wavelength, but a composition of different wavelengths. By changing the power level of three primary colors (because we have 3 types of color receptors in our eyes) we can reproduce different colors for out brain."
] | [
"It is worth noting that this effect is known as Metamerism."
] |
[
"Are human bodies efficient compared to man-made machines like cars?"
] | [
false
] | [deleted] | [
"It depends on your definition of efficient. From an energy-in, energy-out perspective, not at all in any way. We eat a ton of energy, and what do we do with that energy? We turn almost all of it straight into heat. Some of it can go into altitude or speed, but that energy will very quickly be dispersed into heat a... | [
"Arguably. Some of our tissues like muscles, are pretty inefficient in terms of the mechanical work they do per unit of energy(as I recall, muscles are only 20-40% efficient). However, this underestimates the efficiency of the body in several ways(for example, in most machines any energy that is dissipated as heat ... | [
"Well we do need all that heat so I wouldn't considered it wasted or inefficient. If you consider the heat we make that we are extremely efficient compared to other stuff. If we look at how much energy a computer uses to do one simple math problem (say 3x4) and how much energy we use, the computer is more efficien... |
[
"Is it possible for some people to have a more/less saturated vision than other people?"
] | [
false
] | For example, can some people see more saturated colors than other people can? | [
"We can never be sure what the subjective nature of other people's experiences are. These experiences are termed ",
"qualia",
" and they play a big role in the philosophy of the mind. However, we can use self reported information when an individual experiences a change in the quality of their vision. People wit... | [
"With the level of genetic diversity amount humans, I would say it's extremely likely, but I have not heard about any particular studies being done.",
"The difficulty is that it's hard to compare the perception of two separate individuals without being able to see what they see. Even then, the observer would con... | [
"Thanks, that was a good explanation :)"
] |
[
"Are there \"solar systems\" with planets at their center instead of suns?"
] | [
false
] | null | [
"You are right they are called rogue planets, not solar systems. ",
"http://en.wikipedia.org/wiki/Rogue_planet",
" ",
"Yes to having moons (example: ",
"http://en.wikipedia.org/wiki/Cha_110913-773444",
" ), not sure of any with moons that have moons. "
] | [
"Thanks for steering me towards Cha 110913. It's been very interesting reading. Can you correct or confirm some new assumptions?",
"Apparently it was either ejected from a system or was formed in the same way that stars are formed. If similar to stars, a cloud of interstellar gas and dust collected and, throug... | [
"First, I'm an amateur not a pro, so you might want to ask these questions again in brand new posts to attract the real experts that askscience has to offer in this domain. But, I'll try my best: ",
"And the orbiting masses around it are therefore moons. Does that make it a planet at the center of its own system?... |
[
"Is 7 equal to 7.0 and 7.00?"
] | [
false
] | null | [
"Yes, they’re equal."
] | [
"Mathematically, it’s true no matter what the precision is."
] | [
"Thanks. Its true even when when we take precision into consideration right? Thats what the major opposing argument is. That they're not equal because the precision is different."
] |
[
"Is there such a thing as endangered plants???"
] | [
false
] | Do we have plants that are endangered, or records of plants that have gone extinct?? I am not knowledgeable on this subject. I know we find plants preserved in amber and stone, but the ones I recall seeing are things like wheat and ergot and flowers that we still have around today. I would also like to know if humans have ever purposefully eradicated a plant, or of that's possible. | [
"Endangered and extinct plants exist, just like animals. An example: the Arizona Agave with less than 100 plants alive in 1984. There are also plenty of extinct plants. The reason you never hear about them is probably because people care less about plants. They are also often closely related to other species which ... | [
"Yes! Most carnivorous plants, like the North American pitcher plants (genus Sarracenia), are endangered, mostly because of poaching. Basically, pitcher plants were so cool that people would pick entire fields clean. Nowadays, most botanists actually refuse to share the locations of new sites.",
"Additionally, a ... | [
"There is no reason why there would be endangered animals and not plants, but I feel that most of the general public finds animals more interesting, so you hear about endangered animals more.\nPlants are usually easier to grow healthily 'in captivity' than animals, and can be cloned (cuttings, tissue culture) meani... |
[
"Can a radio antenna be used to detect visible light?"
] | [
false
] | Could I place a normal radio or TV antenna in sunlight, have a tuner that I could set to 'red' (400THz) and measure how much red light is present? (in watts I guess) | [
"Theoretically, yes. However, the antenna would have to be so small as to be realistically impossible.",
"At 400 THz, a half-wave dipole antenna would have to be 325 nm long, and thin enough to make that look like a wire (approx two-to-three orders of magnitude, or about 500 pm wide). Also the energy collected by... | [
"Is this a description of the sensors in a digital camera or are those completely different? "
] | [
"Sorry, misread the question.",
"No, a \"normal\" radio or TV antenna is designed for wavelengths orders of magnitude larger than a 400 THz signal. A tuner can compensate somewhat for a mis-matched antenna, but at these extremes, the tuner and antenna deficiencies would overpower the signal itself."
] |
[
"Does a spectrogram from a planet/non-light source get affected by the source of light which we obtain it from? For e.g., if we take a spectrogram of Jupiter, do we have to \"subtract\" the known spectrum of the Sun before we can determine the elements in Jupiter?"
] | [
false
] | To extend the example, since hydrogen from the sun produces a gap in the source spectrum, will it give us a "false positive" reading from the spectrum of the other planets? | [
"I believe I found the answer to my question. Please correct me if I'm wrong.",
"Analysis of the solar spectrum involves ",
"absorption spectroscopy",
". The hot sun acts as a ",
"black body radiator",
" which initially gives us a complete spectrum. As the light passes through the cooler gases nearer to t... | [
"This is the correct answer."
] | [
"It doesn't completely discount them, it discounts some relative amount of them. "
] |
[
"Why doesn't my body get better at fighting off infections with repeated exposures?"
] | [
false
] | null | [
"Hello,",
"We can't advise you about your personal medical situation."
] | [
"Understandable; would my submission be accepted if I phrased it more generally?"
] | [
"I think it would be very difficult to frame this question in a way that we can accept it. If you go into the specifics of your experiences, it's anecdotal. But if you leave that out and make the question general, it's a little open-ended."
] |
[
"How would you describe specific colors to someone who is blind?"
] | [
false
] | How can you accurately convey the image of the color red, for example, to someone who has never seen red? Let's say that this person was born blind, and therefore has never been able to see any colors (eliminating the possibility of using comparisons to things of that color/other colors). | [
"Best answer, synesthesia. "
] | [
"Best answer, synesthesia. "
] | [
"You can't. You can't even accurately describe the color red to someone who is sighted - that is, you can't be sure that what I call 'red' doesn't appear like a different color in your brain. All we can do is say that we both agree that a certain object looks red to ourselves. "
] |
[
"How does Europa still have water available to eject in Saturn's ring system?"
] | [
false
] | Firstly, am I correct in saying that part of Saturn's ring system is made by a sort of 'cryo-volcanism' of Europa ejecting water into space? If so: A) How long can this be maintained? I.e. it is spewing water at a rate of 'x' and we believe this can be maintained for 'y' years? B) What will happen to Europa in the future? Will it just be a waterless, earthy/rocky husk after all of it's water is ejected into Saturn's orbit? C) How long has this been going on for? D) How much water does it have to have been doing it for this long? E) What are the implications for the chances of life if its water is constantly being ejected? Sorry for so many questions, I'm really curious. I've sort of self-resolved in my own mind that maybe some of the water it ejects falls back onto the planet surface in a self-recycling fashion, extending the supply of water from the planet. But equally, I know the solar system has been in existence for billions of years, so I can't see how Europa hasn't already ran out of water! Thanks in advance! | [
"Europa is a moon of Jupiter, not Saturn.",
"Saturn's rings are most likely the result of a large moon which was torn apart by tidal forces millions of years ago.",
"cryo-volcanism wouldn't create a significant ring system there just isn't enough matter being ejected."
] | [
"I think OP might be talking about Enceladus. ",
"cryo-volcanism wouldn't create a significant ring system there just isn't enough matter being ejected.",
"Actually, Enceladus' plumes cause Saturn's ",
"E ring",
". It is definitely diffuse, but it's a ring nonetheless."
] | [
"Yes, you are correct, I meant Enceladus. \nWhen do you think it'll run out of water to keep topping up the E Ring? :)"
] |
[
"My dad asked me to look over the \"Blacklight Power\" site. It's got too much technobabble for me to understand completely (Related: What's a hydrino?), but I pretty much know it's bullshit. However, I need to need to explain it to him, so askscience, can you break it down for me?"
] | [
false
] | <- this is the main summary I tried to read. Couldn't make head or tail of it. Here's the text from the page for people who might not want to give them hits. BlackLight Power, Inc. - Executive Summary Business Presentation An overview of BlackLight's business, technology and market potential. This is a large file which may take a while to load. • BlackLight Power, Inc. is the inventor of a commercially competitive, nonpolluting new primary source of energy that forms a prior undiscovered form of hydrogen called “hydrino” which is very likely the identity of the dark matter of the universe. • Proprietary electrochemical reactants or solid fuels undergo reaction to cause hydrogen to form hydrino with energy released as electricity or heat, respectively. The net energy released from this "BlackLight Process" may be two hundred times that of combustion of the hydrogen fuel with power densities and performance comparable to those of batteries and conventional central power plants, respectively. • Water can be used as the stored hydrogen, generated on demand by electrolysis using less than 1% of the electrical output. With the elimination of fuel and fuel infrastructure costs, the operational cost of BlackLightPower generators is likely to be very inexpensive. Moreover, the process does not give rise to pollution, green-house gases, or radiation as conventional systems do. • The Company has developed three systems for producing electricity powered by forming hydrinos: one electrochemical and two thermal systems. A CIHT (Catalyst Induced Hydrino Transition) cell generates electricity directly from hydrogen. But, unlike a conventional hydrogen fuel cell, the cost is forecast at $25 per kW compared to thousands per kW for a fuel cell. This is in part due to the CIHT cell’s electrical energy released per hydrogen being over 200 times greater, and the CIHT materials being inexpensive. Moreover, fuel cells can’t use water as the source of hydrogen, since their product is water. For CIHT, no fuel infrastructure is required to provide on-site power allowing the CIHT cell to be autonomous. • BlackLight Power is focused on advancing CIHT technology to produce power to ultimately sell directly to consumers under power purchase agreements. Rapid dissemination at nominal historic cost is expected by deploying many autonomous distributed units that circumvent the huge barriers of entry into the power markets such as developing and building massive billion-dollar power plants requiring enormous thermally-driven mechanical generators with their associated power distribution infrastructure. This is especially advantageous in emerging markets. • Essentially all power sources of all sizes: thermal, electrical, marine, rail, aviation, aerospace, as well as, automotive sources become untethered from an electrical distribution or fuel infrastructure and are also independent of the sun, wind, or other external variable power sources. • A CIHT electric car is expected to have a range of 1500 miles on a liter of water. This direct application of the BlackLight Process to motive power has the potential of unsurpassed capability in terms of range, capital cost, power, logistics, and pollution abatement to zero, including zero carbon dioxide emission. Moreover, the compact automotive unit could be plugged into the electrical panel to power the owner’s home with enough power to spare to also power the neighborhood. BlackLight plans to pursue licensing, strategic partnerships, and leasing in motive power markets. • In addition, the Company has developed thermal producing solid fuel chemistries that in turn can be thermally regenerated. Thus, the Company believes that continuous generation of power liberated by forming hydrinos is commercially feasible using simplistic and efficient systems that concurrently maintain regeneration as part of the thermal energy balance. The system is closed except that only hydrogen consumed in forming hydrinos needs to be replaced. • Chemistries and engineering designs have been developed using the corresponding experimental parameters for power and regeneration for two thermal-Rankine systems. One comprises a multi-tube thermally interacting bundle of cells wherein cells producing power provide heat to those undergoing regeneration. As a system, the power output is constant. The capital costs are projected to be about $1400 per kW electric. The other comprises an array of reactor cells wherein power and regeneration chemistries occur synchronously, and each cell outputs constant power. The capital costs are projected to be about $1050 per kW electric. • BlackLight is non-exclusively licensing its thermal process to make power for a fixed royalty payment per kilowatt-hour of thermal or electric. To date, the Company has licensed the rights to produce approximately 8,250 MW of new electrical power to seven companies, including five electrical utilities and two independent power producers. Collectively, these utility companies own, purchase, or manage electric power production of approximately 7,600 MW and service nearly one million customers. The avoided fuel costs from these agreements could be in excess of $2 billion per year. • Electrical power from the CIHT cells, thermal power from the solid fuels and their thermal regeneration, hydrinos from both synthesis reactions and as a product of the CIHT cells and the solid fuels, as well as the light signature of the formation of hydrinos, and other signatures of the BlackLight Process have been independently validated and published in scientific journals and reports. • The theory upon which BlackLight's technology has been developed is based on the classical laws of physics. The Company recently released the finalized Grand-Unified Theory of Classical Physics that comprehensively addresses many of the basic problems in chemistry and physics using these physical laws without using approximations or pure mathematics, devoid of physics, as is the case for the incumbent atomic theory of quantum mechanics. BlackLight's wholly owned subsidiary, Millsian, Inc., is dedicated to developing computational, chemical-design software tools based on solving molecular structures using these laws. The essentially real-time, analytical solutions of the precise physical structure of molecules of boundless extent and complexity, not possible using quantum mechanics, further validates the classical theory relied on by the Company. TL;DR | [
"…new primary source of energy that forms a prior undiscovered form of hydrogen called “hydrino” which is very likely the identity of the dark matter of the universe.",
"At this point I stopped reading and skipped to the end, where I found:",
"The theory upon which BlackLight's technology has been developed is ... | [
"A hydrino is almost certainly a completely fictitious particle this company made up. We don't yet know (for sure) what dark matter is. No one does, much less some \"power generation\" company. The rest of the nonsense seems to fall into place after this.",
"And the last point. Particularly \"...without using app... | [
"Why don't you just read the Wikipedia article on the \"company\". ",
"http://en.wikipedia.org/wiki/Blacklight_Power",
"I especially like the following quote \"By 2009 BLP had raised about $60 million in venture capital, and claims to have seven commercial agreements to license BLP energy technology for the pr... |
[
"How are memories stored? Could specific parts of the brain be targeted to erase specific memories?"
] | [
false
] | Are memories stored like files on a hard-drive where you can target the information directly, or are memories stored across the brain in a "holographic" type way where destroying parts of the brain would merely weaken memories but not destroy specific ones? | [
"See ",
"this thread",
" for some relevant information. There is no evidence to suggest that memories are stored in particular places in the brain. It is true that particular parts of the brain are involved in different types of memories, but there is no evidence to suggest that those are the places where they ... | [
"Different ",
" of memory are indeed stored in different parts of the brain, somewhat. For example, the hippocampus ( a part of your brain) is shown to store spatial memory (e.g. your knowledge of the roads in your neighbourhood). It has been observed that taxi drivers have on average larger hippocampi than the g... | [
"Here are some links you may find relevant to your question. The short answers to your two questions are yes and perhaps, though it would be very difficult to parse the different aspects of single memories from other memories. \n",
"http://www.quora.com/Are-memories-stored-physically",
"\n",
"http://www.quora... |
[
"Is it easy to create a strong solenoid?"
] | [
false
] | null | [
"You think a power source that can supply 5 Amps is easy to find?"
] | [
"Not sure. I was thinking just using the wall outlet and finding a low value resistor. Haven't actually tried to find it, though. That aside, is the calculation a good estimate given the conditions? There's probably overheating issues but I'll figure that out later."
] | [
"Your wall outlet is not going to allow you to draw 5 Amps. 5 Amps is an enormous current, ",
" more than enough to kill you.",
"Creating a low-resistance path between the holes in your outlet will just trip the fuse."
] |
[
"Does exercise have any effect on height growth?"
] | [
false
] | I understand that height growth is basically genetics/environmental factors but what effect exercice like basketball or any sports can do to potentialize our height growth during puberty when you already have good nutrition? | [
"One study, it states that human growth hormone secretion can be stimulated by vigorous exercise and the conclusion is - \"We conclude that the GH response to acute aerobic exercise is augmented with repeated bouts of exercise\". The study can be seen here - ",
"http://jap.physiology.org/content/83/5/1756.full",
... | [
"Height can be affected by factors such as diet ",
", that point being genetics. Someone with poor nutrition will be shorter than someone who is well fed, all else being equal.",
"Basketball players are not tall because they play basketball. They play basketball because they are tall.",
"Therefore to answer y... | [
"Workouts are mostly to increase your physical capabilities. Workouts will allow them to jump higher but not grow more. ",
"Increasing muscle mass is natural, increasing bone structure isnt."
] |
[
"Assuming we could live on the surface of the moon or Mars, how much radiation would we be exposed to?"
] | [
false
] | I've been reading some sci-fi books about colonizing the moon and Mars and was curious about the radiation load a human would experience over the course of a year in either of those locations. Also, what kind of radiation load would a human experience living a year in the International Space Station? | [
"The ",
"ISS Wiki article",
" states that astronauts in the ISS get the same radiation dosage in one day as someone on Earth gets in one year. So roughly 365 times more. ",
"The ",
"Colonization of Mars Wiki article",
" states that the dosage on Mars would be 2.5 times higher than on the ISS."
] | [
"The colonies will probably have to be underground."
] | [
"Why would it be higher on the surface of a planet? Is it the radiation shielding on the station, or the fact that the station is close enough to the earth's magnetosphere to shield the station?"
] |
[
"How can a supermassive black hole explode?"
] | [
false
] | I read an article that talks about the supermassive black hole at the center of our galaxy exploding relatively recently . How does a black hole explode? I don't pretend to know much in this area but I would think the energy needed for anything to escape a black hole would be impossible to reach, thus negating any "explosion" anything from escaping the event horizon. The article says it was "like a lighthouse for 200k light-years into deep space." How? | [
"It's a poorly written headline that's leading to a misconception. The black hole did not explode. You are correct, nothing can escape the event horizon. The ",
"original release",
" has the phrasing that the \"centre of the Milky Way exploded\" which is subtly but crucially different from the \"black hole at t... | [
"Yes, Hawking radiation does not originate from inside the event horizon, but just on its edge."
] | [
"Classic newspaper article confuses more than helps people.",
"Black holes don't explode.\nSome can be active however. A galaxy with an active super massive BH at its core is called an AGN. \nSometimes these can produce flares.\nThat's what they were referring to.\nThe flare event."
] |
[
"Is it safe to fix my french press with super glue?"
] | [
false
] | null | [
"The polymer formed by the superglue curing process does not readily degrade when exposed to water, and it is low in extractables, you should be fine from a chemical exposure stand point. ",
"The bigger question is whether or not the glue will be sufficient to fix what you are attempting to fix, and that I can n... | [
"Source? ",
"Cyanoacrylate polymerizes in the presence of and is insoluble in water.",
" How will using it have anything to do with burning yourself?"
] | [
"I realise this is a fixit forum but after much personal experience, getting a quality replacement 'beaker' via ebay has stood up as the longest solution. Another common source previously used has been thrift stores."
] |
[
"Can cancer get cancer? E.g. can a cancerous tumor grow on another cancerous tumor?"
] | [
false
] | null | [
"Cancer usually refers to the uncontrolled and harmful growth of cells. Parts of a tumor can become malignant, metastasize, or become histologically distinct (and thus be different from the original tumor's pathological progression), but your assertion that cancer can \"grow on\" other cancer tumors doesn't make se... | [
"A tumor is a heterogeneous group of cells undergoing mutation and selective pressure from their microenvironment. In fact, within the same tumor, there will be subpopulations of cells with different mutations that are competing for the same resources. My point here is that a tumor can't really be thought of as a s... | [
"I'd like to know if that second growth would be deleterious to the prior growth's health. "
] |
[
"Why are sinkholes almost always circular in shape?"
] | [
false
] | null | [
"Sinkholes occur when erosion has been going on below them; that much seems obvious. However, it's worth condiering that type of erosion.",
"The most common form is chemical weathering of limestone, caused by movement of groundwater, which in general tends to concentrate along particular weak joints or fractures ... | [
"Thanks for the reply.. I do get all of that, but why is it almost always a perfect circle? Why not just some weird misshapen hole, instead?"
] | [
"Because what you have is a weak ",
". The failure is at a point location, and then a failure cone grows up from it."
] |
[
"Is it possible, once close enough to earth, to send a satellite into orbit around a comet? or to at least put a fixed beacon onto it?"
] | [
false
] | I say this because apparently we will be having a "once in a civilization" comet cruising around earth. | [
"There have been a number of ",
"comet rendezvous missions",
". Comets come fairly close to the Earth often, but that doesn't necessarily make them easier to rendezvous with. The big deal about this upcoming one will be its size and visibility."
] | [
"This comet seems to have a velocity of around 50 km/s relative to Earth when its close to us. That's way too fast for us to catch it. And besides that, it doesn't even come all that near us. We could probably collide something with it or fly something through its tail if we wanted to but for a smooth landing you n... | [
"seems like it gets VERY close to mars. thanks for the link!"
] |
[
"Do you burn more calories when you're sick?"
] | [
false
] | When you're sick you can experience symptoms like increased mucous production and fever. I imagine that since the body has to deal with these problems it would have to spend more energy. Anybody able to expand on this idea? Side question: when you have a cold, where the hell does all of that mucous come from? It's non-stop! Thanks for all the info guys. This subreddit is awesome! | [
"Yes, baseline energy usage increases ~15% with each degree increase in temperature.",
"Inflammation dumps a lot of chemicals into your blood that fire up the breakdown of fat and glycogen stores. Basically you mobilize your body's stored energy so that it can be used to fight infection.",
"Side question: Your ... | [
"Celsius."
] | [
"baseline energy usage increases ~15% with each degree increase in temperature.",
"Fahrenheit or Celsius?"
] |
[
"why do our bodies need to maintain ~98-99 degrees?"
] | [
false
] | is there a scientific reason why our bodies need to be at around this range? why wouldn't we work as well at .. say 92 degrees, or 105? (if this has been asked before, I'll apologize in advance :) ) | [
"You have proteins in your body that fold at certain temperatures and pHs. These proteins repair and replicate DNA, catalyze reactions, and run your metabolic systems. Any higher/lower, and the proteins would become unstable and denature, and you would die."
] | [
"From what I remember of Biology:",
"This is due to Homeostasis.(Also known as maintaining a stable internal environment.) We are the heat we are because we're at the most optimal condition inside at this heat.(This applies to energy usage, protein conditions, et cetera.)",
"Only other reason I could find is th... | [
"The body can be thought of as one giant test tube. At any given time, there are thousands upon thousands of reactions going on. Chemical reactions are very dependent on temperature. In addition to that, the body uses enzymes, which are proteins, in order to carry out the reactions efficiently. Protein structur... |
[
"If you were in outside of the solar system with an apple. Would you have enough mass to have it revolve around you?"
] | [
false
] | null | [
"If you were a point mass of say 80 kg, an apple could orbit you at a distance of 1 m in approximately 24 hours. Orbital velocity would be about 27 cm/hour. There are terrestrial slugs faster than this by orders of magnitude. ",
"It would be impractical for two reasons: \nThe orbit would not be very stable becaus... | [
"In astrophysics terms, while there is no distant horizon where the apple will never return, there IS a set of speeds where you will not be seeing the apple again. There are three velocity regimes the apple can be in. In the slowest, the apple is not moving fast enough to escape (it is moving slower than 'escape ve... | [
"If we had a large and roughly spherical spaceship do you think it would be feasible to have a few small cameras/probes orbiting it to monitor for surface impacts?"
] |
[
"How does cheatengine work? isn't it the job of the OS (ie, windows) to prevent programs from modifying the data of other programs?"
] | [
false
] | null | [
"Usually they use ",
"DLL Hooking",
". Basically, they trick the process into loading the exploit into its own memory space. Thus, they're not trying to modify another process's memory space which the OS does shut down. "
] | [
"The point of the OS is to prevent programs from ",
" modifying the data of other programs. If a program needs to, there are APIs like ",
"ReadProcessMemory",
" that can be used to read & write the memory of other processes. ",
"These APIs also obey security restrictions, so for example, you can't modify th... | [
"What about statically linked binaries?"
] |
[
"Noether's theorem: Are there any simple physics problems that can solved by making a symmetry argument directly rather than by applying the corresponding conservation law?"
] | [
false
] | I'm not entirely sure this question makes sense. What I'm asking for is a simple textbook-type physics problem that would normally be solved by applying conservation of energy, momentum, or angular momentum that can also be solve by making an argument directly from the corresponding symmetry principle. Take, for example, the frictionless roller coaster problem where you can easily calculate its speed at any point by conserving energy. Is there a corresponding way to solve the problem directly from the principle of time symmetry without going through a fully general derivation of energy conservation via Noether's theorem? If this question doesn't make sense, or is not possible, could someone explain why at a level understandable by an engineer with a decent grasp of undergraduate physics? | [
"I think what you are imagining isn't really feasible. Here's why.",
"In Noether's Theorem, we are identifying a symmetry of the Lagrangian or, more properly, of the action. This does not lead to a conservation law until you invoke the equations of motion (the Euler-Lagrange equations).",
"While we can use sy... | [
"The symmetries you refer to here are not the kinds of symmetries involved in Noether's Theorem. Noether's Theorem refers to symmetries of the action, not symmetries of some particular physical system."
] | [
"Very interesting, thanks, I will have to ponder this a bit but I think I see where you're going."
] |
[
"From a chemical and biological perspective, why and how does semen decompose from a gelatinous form to a viscous liquid after sitting for about 5 minutes?"
] | [
false
] | [deleted] | [
"It's because it's protein based, and high temperatures make protein structures go weird and congeal. (Similar to when you boil an egg.) This might be an evolutionary response that causes it to be harder to 'wash out' from inside the female, as it congeals after ejaculation into the vagina. ",
"It washes off perf... | [
"Also, why does it congeal when exposed to hot water in a shower?"
] | [
"Semen and ejaculate are composed of a very high concentration of proteins. Upon temperature change and pH change these proteins and cells will degrade and die. Denatured proteins and DNA turn into a gelatin like consistency (DNA turns into clear snot). It is exactly like egg whites. "
] |
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