title stringlengths 4 300 | selftext stringlengths 0 9.63k | answers.text stringlengths 55 11.4k | answers.score int64 2 32.7k | title_urls.url list | selftext_urls.url list | answers_urls.url list | sent_vec list |
|---|---|---|---|---|---|---|---|
what do trig functions with h mean? i.e sinh(x) | i looked it up and it had something to do with being hyperbolic. but i honestly don't understand what that means. also how do they relate to regular trig functions? can they be interchanged? lastly how do integrals have to do with them and why haven't i learned about this earlier in calc 1? | cartesian plane, circle with radius, circle ====== [if you have a a circle with radius 1 centered on a cartesian plane, you can describe it by x^2 +y^2 =1. if you pick a point on the circle with some angle t separating it from the horizontal, the horizontal distance to that point is cos(t) and the vertical distance is ... | 36 | [] | [] | [
"http://www.sosmath.com/trig/hyper/hyper01/etc/hyper012.gif",
"https://upload.wikimedia.org/wikipedia/commons/b/bd/Sine_and_cosine_animation.gif"
] | [
-1.4001703262329102,
0.31995347142219543,
-0.8909344673156738,
-1.7694406509399414,
-2.754711151123047,
-0.15849673748016357,
2.019704818725586,
0.20795166492462158,
2.0262880325317383,
-0.3665081262588501,
1.7524281740188599,
-0.8334238529205322,
1.6781197786331177,
-1.0705225467681885,
... |
can someone explain rubies with a cubic crystal pattern? | recently i bought some rough rubies from a source i trust and have bought from several times in the past. most of them were normal and i also got a few nice sapphires along with them. however, when i was going through the stones i noticed something weird. many of the rubies seemed to have a cubic crystal pattern. neat ... | feed the discussion, cleavage faces, give a definitive ====== of course, one cannot give a definitive answer without acces to the material, but there are a few bits of info which might help to feed the discussion: * are these 90° surfaces crystal faces or are they cleavage faces? * might they perhaps be a parting surfa... | 3 | [] | [] | [] | [
-3.756074905395508,
1.070400357246399,
0.2995520830154419,
0.17872634530067444,
-3.1012537479400635,
-2.3622243404388428,
1.5740165710449219,
0.6026602983474731,
0.2803378701210022,
-1.1727412939071655,
0.08925386518239975,
-1.0158107280731201,
0.1213940978050232,
-0.6704423427581787,
2.... |
how do timers and cron work in computers? | i've always wondered how timers are actually implemented in computers. e.g. say i put a thread to sleep for 1000ms. my thread blocks but what in the kernel is monitoring the time and waking the thread. my other question is how is cron implemented without chewing up cpu? it seems like it would have to check the time and... | timer hardware, timer, hardware ====== it's all dependent on interrupts from timer hardware. the kernel configures the timer hardware and knows to go look and see what events (such as waking your sleeping process) it may need to do when the timer interrupt handler runs. and there are a couple of different ways timer ha... | 3 | [] | [] | [] | [
-1.567614197731018,
-0.7133410573005676,
-0.38582825660705566,
-1.406114935874939,
0.5932010412216187,
-0.8178048729896545,
-1.436467170715332,
0.3636234402656555,
1.1738024950027466,
0.5885589122772217,
-0.8441755771636963,
0.9232652187347412,
-1.4202584028244019,
0.14699117839336395,
-... |
how does the iodine clock reaction work? | how does it work? | iodine formed back, iodide ion, quickly changed back ====== first the iodate ions and iodide ions present in the solution are reduced to molecular iodine (to be soluble in aqueous solution, the molecular iodine is actually complexed with an iodide ion to make the i3- triiodide ion--but i show it here as i2 for clarity)... | 4 | [] | [] | [] | [
-1.9565082788467407,
0.7911726832389832,
1.1356613636016846,
0.8208104372024536,
-0.20747525990009308,
-2.8197202682495117,
2.6520352363586426,
0.5751294493675232,
0.3716784417629242,
1.2587890625,
2.0821728706359863,
-2.4920849800109863,
1.4667259454727173,
-1.0998221635818481,
0.204789... |
i just learnt that somalians traditionally consider colustrum to be very unhealthy and avoid it - in what conditions could this be considered to be safest practice? | i'm researching somalian culture before i start language teaching next week and found a document that claims somalis avoid colostrum. (_url_0_) i was under the impression that it was really, really good for babies so i'd love to know where this idea may have stemmed from. are there any environmental issues that could a... | mothers nipple entering, mom has hiv, cultural phenomenon ====== its a cultural phenomenon as the only risk comes from external bacteria on the mothers nipple entering the baby[or if the mom has hiv, for example]. its a naturally produce substance from the mother so it will not harm the child, but in fact act to improv... | 2 | [] | [
"http://ethnomed.org/culture/somali/somali-cultural-profile"
] | [] | [
-1.4018006324768066,
-0.6082262396812439,
-1.0049927234649658,
1.2850435972213745,
-0.6774275302886963,
0.10100293159484863,
-1.3040142059326172,
0.5432673692703247,
0.6142091155052185,
1.0263866186141968,
1.3264127969741821,
-1.9402458667755127,
-1.1733911037445068,
2.1577110290527344,
... |
how and where is the cmbr measured? | i understand that the cmbr comes from everywhere, but for a survey such as cobe or wmap are they using magnification? are they trying to look for the cmbr at 13.3 light years away? | direction, universe, microwave ====== the universe doesn't really need magnifying. it's quite big already. to detect the cmbr, you need an instrument that detects microwave radiation - essentially a microwave camera. you point it at the sky in one direction, record how much microwave energy is coming from space in that... | 4 | [] | [] | [] | [
-0.05861742049455643,
1.1715518236160278,
0.13955223560333252,
0.5243875980377197,
0.6440575122833252,
-0.9112637639045715,
-1.3217031955718994,
-0.8001285195350647,
0.947733461856842,
-0.7283046841621399,
0.13017907738685608,
-0.23215380311012268,
-0.158257395029068,
-0.7565358281135559,
... |
can someone explain the reaction that makes retrobrite work? | retrobrite is fixing the color on old plastic by soaking it in hydrogen peroxide while it's out in the sun. _url_0_ i'm just curious how this works? | hydrogen peroxide, thing that bleach, tend to rip ====== the thing that bleach, hydrogen peroxide, and sunlight have in common is that they tend to rip apart long, interesting molecules. long, interesting molecules such as lycopene, which gives tomatoes and other plants their red color, stop being red if they are chopp... | 8 | [] | [
"https://www.youtube.com/watch?v=qZYbchvSUDY"
] | [] | [
-2.0837302207946777,
0.24162055552005768,
-0.23323389887809753,
2.0177078247070312,
2.366905450820923,
0.6903537511825562,
1.4548015594482422,
0.97812420129776,
1.281417965888977,
0.1493435800075531,
-0.009232133626937866,
0.7044505476951599,
-1.0056853294372559,
-0.4056853652000427,
0.4... |
just how sensitive are the curiosity's organic-compound-detectors? | this question stems from a [discussion](_url_0_) on /r/mars about the possibility of curiosity finding viruses as evidence of past life. is curiosity sensitive enough to find viruses on mars? | finding dead bacteria, answering the question, past than finding ====== msl is more about answering the question how habitable some areas on mars might have been for life in the past than finding dead bacteria or viruses. it is currently investigating areas that look like dry riverbeeds. once we found the most habitabl... | 4 | [] | [
"http://www.reddit.com/r/Mars/comments/16hh1b/has_any_onboard_labs_looked_for_viruses_on_mars/c7w80uj"
] | [
"http://msl-scicorner.jpl.nasa.gov/Instruments/MAHLI/",
"http://en.wikipedia.org/wiki/Laser-induced_breakdown_spectroscopy"
] | [
0.1078321784734726,
-0.13505184650421143,
1.268599033355713,
0.5280590653419495,
1.3859531879425049,
-2.026082992553711,
1.3852858543395996,
-0.5679811239242554,
0.5099999308586121,
0.4117550551891327,
0.7649914622306824,
-1.3292865753173828,
0.02953585982322693,
0.26083001494407654,
0.5... |
what would happen if a person could bend light in a perfect circle? | my dad told me a few times that if a person could bend light in a perfect circle, he would be very rich indeed. i didn't understand then, and i don't understand now. he may have mentioned perpetual energy. | url, light to travel, circular path ====== getting light to travel in a circular path isn't anything super exciting and is done routinely. these structures are called [optical ring resonators](_url_2_). no perpetual energy here, but it does have widespread applications in fiber optics. [here's what they look like](_url... | 20 | [] | [] | [
"http://www.nature.com/nature/journal/v435/n7040/images/nature03569-f2.2.jpg",
"https://www.youtube.com/watch?v=KR8u3uu7RpI",
"http://en.wikipedia.org/wiki/Optical_ring_resonators",
"https://www.youtube.com/watch?v=luPLiOSnyHU",
"https://www.youtube.com/watch?v=m4j2y53f1sQ"
] | [
-0.30356234312057495,
-0.3090895414352417,
0.4094141125679016,
0.21784959733486176,
-0.08694329857826233,
-0.9249868392944336,
0.7659358978271484,
-0.35472506284713745,
0.11292198300361633,
-0.09369951486587524,
0.8745381236076355,
0.7208554744720459,
-0.026934877038002014,
0.5578342676162... |
a question about the conductivity of water vs people. | this may sound like a dumb question, but i have to ask. if a person is in a body of water without being able to touch or make a direct connection to ground and electricity is introduced ( lightening, toaster oven, whatever) will that person be electrocuted? would salt or fresh water make a difference? my thought proces... | depends, electricity, current ====== it depends. if they are in the path(s) that the electricity is taking to get to ground, and there is enough electric current flowing, it will shock or kill them. people are more conductive than fresh water, and similarly conductive to salt water, so they don't get any significant be... | 5 | [] | [] | [] | [
-0.4674746096134186,
0.30813896656036377,
0.5834205150604248,
0.9399406313896179,
0.8231106400489807,
-1.20589017868042,
0.9952036142349243,
0.7975066304206848,
-0.5723550319671631,
0.0820913165807724,
0.7535344362258911,
0.18920812010765076,
0.32516178488731384,
0.5833269357681274,
0.66... |
what is the significance of the derivative of the circumference? | the derivative of the area of a circle is the circumference. when you take the derivative of the circumference with respect to the radius, you get 2pi. does this have to do with how many radians are in a circle or does it have other significance? also we can say the same about the derivative of volume being surface are... | radius, infinitesimal change, change ====== so a derivative is a rate of change, right? so we take the derivative of circumference with respect to radius, and like you say, we get a constant; 2pi. so we asked, "what is the ratio of an infinitesimal change in circumference to an infinitesimal change in radius?" and our ... | 94 | [] | [] | [
"http://www.reddit.com/r/askscience/comments/28d19y/why_is_the_derivative_of_the_volume_of_a_sphere/"
] | [
-0.8882584571838379,
-1.0788836479187012,
-0.31906241178512573,
-0.3478303551673889,
-2.5853378772735596,
-0.8690489530563354,
-0.08651760965585709,
1.2688300609588623,
2.821160078048706,
-0.7661232948303223,
2.053344964981079,
0.08309352397918701,
1.3222262859344482,
-0.5000061392784119,
... |
how much heat is given off by wires and powerlines? | one side effect of electrical resistance is heat, known as joule heating or resistance heating. this is pretty obvious on an electric stove top, where the heating element is actually an electrical conductor with enough current and resistance to create a lot of heat. but every conductor has at least some resistance (exc... | feet of wire, wire, feet ====== if you assume all the wiring in your house is 12-2, and that your house has 4,000 feet of wire, then you have 8,000 total feet of wire (4,000 to outlets and 4,000 back to the main). for this length of wire, you'd see something like 6 ohms resistance. now, we need an estimate of the curre... | 2 | [] | [] | [] | [
-2.132108688354492,
1.7548233270645142,
1.6753575801849365,
1.9791101217269897,
-2.2937917709350586,
-1.8724260330200195,
0.3010432720184326,
3.1440253257751465,
0.8189485669136047,
-1.5482118129730225,
-0.3624219298362732,
1.950764536857605,
-0.8077843189239502,
-1.6496264934539795,
-4.... |
can someone explain how causality could be 'broken' by something like 'effective' ftl? | can someone explain how causality could be 'broken' by something like effective ftl (effective here meaning you reach your location faster than light would, but don't necessarily travel faster than light at any point)? suppose you had a warp drive, and you watched a star explode from close by, then jumped 10 light minu... | reference frame, faster than light, original reference frame ====== if you travel faster than light, there is some reference frame in which you arrive *before* you leave on your journey. someone in that reference frame could then send a ftl message to your starting point, which could go backwards through time in the or... | 3 | [] | [] | [
"http://books.google.com/books/about/Geometry_Relativity_and_the_Fourth_Dimen.html?id=IsiUudN5pD0C"
] | [
-1.3040540218353271,
-0.8316113948822021,
-0.7326204776763916,
-0.41525202989578247,
0.17900577187538147,
-0.9056075811386108,
-1.3668396472930908,
-0.9213917255401611,
1.567615270614624,
-1.316074013710022,
0.8448434472084045,
0.15261846780776978,
-0.31516680121421814,
0.29736462235450745... |
has there even been a paper with a p-value < 10^-4 or less that was later contradicted by a different study with a larger sample size? | i've seen papers with p < 0.05 and p < 0.01 that were demonstrated as false positives when studies with sample sizes ~100 times larger were conducted. however, i don't remember seeing this happen with papers proclaiming p < 10^-4 findings. | wrong things happening, reasons, experimental design ====== i can't think of a specific example, but it's pretty likely, for two reasons. first, experimental design can be flawed, leading to people being really certain of wrong things happening. second, there are a _lot_ of papers out there. enough that even 10^-4 is l... | 3 | [] | [] | [] | [
-0.514029860496521,
-0.3196200728416443,
0.4685465395450592,
-0.6015864610671997,
0.11354102194309235,
-0.6078300476074219,
-0.3603203296661377,
-0.255578875541687,
0.5993025898933411,
-0.2165418267250061,
-0.11035852134227753,
1.0197129249572754,
0.28619861602783203,
-0.3247998058795929,
... |
does headbanging, dancing, and rapid velocity shifting movements (sports and such), aerobic neck workouts, etc cause brain damage? | i'm wondering if doing neck rotations, head turns, headbanging to music, running in different directions rapidly when playing basketball/soccer/football, and such cause brain damage. any studies on this? | brain, activities you listed, concussion ====== you're basically asking two different questions (even though you didn't necessarily know you were... how exciting). 1.)the first is, "can [the activities you listed] cause a concussion/brain injury?" a concussion occurs when there is a sufficient level of force applied to... | 33 | [] | [] | [
"http://www.abc.net.au/science/articles/2008/12/18/2449866.htm",
"http://scholar.google.com/scholar?q=soccer+heading+mri&btnG=&hl=en&as_sdt=0%2C11"
] | [
-1.5386959314346313,
-2.6946847438812256,
1.7254657745361328,
-1.9356003999710083,
-0.13790258765220642,
0.9138445258140564,
-0.03623113036155701,
2.350184202194214,
1.704788088798523,
0.12879543006420135,
3.537672758102417,
1.9666414260864258,
0.9760276675224304,
0.20781809091567993,
-0... |
is there something like an "immediate concentration overflow"? | i'm a math undergraduate, and when i learn mathematics, there are times where i try to "switch a button" inside my head in order to gather and connect much more information at a time. now, this might seem kind of weird, but it actually works. do you remember the first time ever you drank a big cup of coffee or somethin... | inducing your adrenaline, adrenaline in order, metres versus jog ====== you may be inducing your adrenaline in order to think as best as you can. doing so burns calories fast and if you're not prepared, you can easily burn out much the same as if you were to sprint for 20 metres versus jog for 100 metres. you are able ... | 2 | [] | [] | [] | [
0.6106441020965576,
0.36643683910369873,
-0.7248908281326294,
0.09203830361366272,
0.546139121055603,
-0.5518985986709595,
0.0473601371049881,
1.057900309562683,
0.39787203073501587,
-0.052236199378967285,
0.1788165271282196,
-0.4580744504928589,
-0.6809191107749939,
-0.3078407347202301,
... |
what happens when teleported particles/states collide? | **first a disclaimer:** my understanding for this particular topic in qm is a bit shaky, so there may be a chance that this question comes from my misinterpretation of quantum teleporting. if this is the case i apologize! **my question:** would it be possible to "collide" particles together by teleporting two different... | remote place, taking a bit, bit of matter ====== no, because quantum teleportation is not taking a bit of matter and somehow getting it to a remote place. in quantum teleportation, the process is that bob manages to turn a particle in his possession into the state that one of alice's particles previously was in. bob ca... | 7 | [] | [] | [] | [
-0.4797062277793884,
-0.12184429168701172,
-0.10008838772773743,
0.5960128307342529,
-0.6831408739089966,
-0.8041107654571533,
1.2158169746398926,
-0.2760951519012451,
0.26177942752838135,
0.07338033616542816,
0.25371795892715454,
-0.343271940946579,
0.4610227346420288,
0.395671546459198,
... |
what limits us technologically from being able to shunt blood to/from our circulatory system and effectively perform all necessary functions artificially? such as maintaining o2, co2, glucose, etc concentrations... | obviously completely replacing all organ functions would be extremely complicated, but it seems like some minimal functions could be accomplished in the near future that could keep your brain and spinal column healthy enough to survive indefinitely barring other complications. maintaining the good stuff in necessary co... | big issue, blood is sticky, goops up machines ====== a big issue is that blood is sticky and it goops up machines and forms clots that can kill you. this is why bypass has to be done in a finite amount of time. | 2 | [] | [] | [] | [
-0.07165512442588806,
0.31482675671577454,
0.009948700666427612,
-0.3000246584415436,
-0.32344403862953186,
-0.5016351938247681,
0.6460101008415222,
0.24729356169700623,
0.793446958065033,
0.09185107797384262,
0.137582927942276,
0.006263953633606434,
-0.08293406665325165,
-0.03218648582696... |
what is surface plasmon resonance? how can it be exploited? | just an explanation of the phenomenon, starting with what a surface plasmon is. my understanding is that it has to do with the "ocean of electrons" that results from metal atoms bonding to each other. because the electrons are in this sort of soup, but repel one another, they tend to aggregate into waves or clusters (t... | free electron gas, electron model, basically ====== basically, yes. in metallic solids, the valence electrons can be very simply viewed as a gas of sorts (aka the free electron model). this "free electron gas" can experience collective oscillations (at the surface or in the buik), and can be excited by the appropriate ... | 2 | [] | [] | [
"http://en.wikipedia.org/wiki/Surface_enhanced_Raman_spectroscopy"
] | [
-2.0669796466827393,
0.4530036151409149,
-0.1645614355802536,
0.04893690347671509,
-0.4707561135292053,
-1.3371002674102783,
0.030954182147979736,
-0.0315835177898407,
0.006344974040985107,
-0.44662582874298096,
0.5067770481109619,
-0.6915804743766785,
0.48614490032196045,
-0.2740977704524... |
how does surface plasmon resonance (spr) work? | i was reading [this _url_1_ article](_url_0_) and it sent me on a long wikipedia walk reading about surface plasmons and related materials. then, after some googling, i found [this video](_url_2_). in the video, it is mentioned that reactions that take place on the ligands result in a shift in the dark spot on the dete... | reflected back, hitting the underside, thin piece ====== in spr you're hitting the underside of a thin piece of metal with light and measuring the light that is reflected back. do this at a bunch of different angles and you get an spr curve. when you modify the other side of the sensor, through say, binding an enzyme t... | 3 | [] | [
"http://phys.org/news/2014-04-ersb-nanostructures-applications-infrared-terahertz.html",
"phys.org",
"https://www.youtube.com/watch?v=sM-VI3alvAI"
] | [] | [
-0.8992496728897095,
-0.29466211795806885,
0.5656719207763672,
1.0011358261108398,
0.4107707440853119,
-1.0598539113998413,
0.46140220761299133,
0.5746970772743225,
0.7612387537956238,
-0.059228330850601196,
0.6770578622817993,
-0.00914602167904377,
-0.4861065447330475,
-0.5650878548622131... |
what's the obstacle preventing us from making artificial synapses? | a synapse is where one neuron ends, and one or more cells, neurons or not, receive the signal. so far, active prosthetics have been using leftover muscle groups or eeg - i'm not aware of any artificial synapses that connect to a neuron directly. is it a foreign body rejection problem? are the structures just too small ... | lost an arm, send the output, neurons ====== firstly, where are these presynaptic terminals your thinking of? that is, if you are imagining someone has lost an arm, and you're going to send the output of the cns, you must be imagining that there are some presynaptic terminals just kinda... lying around, waiting for you... | 8 | [] | [] | [] | [
-0.48626503348350525,
-1.837471842765808,
-1.0879065990447998,
-1.0431286096572876,
-4.029300689697266,
-1.3675168752670288,
2.114750862121582,
-0.3894938826560974,
3.4302144050598145,
1.2949461936950684,
1.9889549016952515,
1.5775761604309082,
-0.04865926504135132,
0.8365351557731628,
-... |
so what's the deal with the climatologist james hansen? he seems to be a controversial character, with many people calling him a "hack," and a "bad scientist." | hansen turns up a lot in climate-change studies and whatnot. he seems to have a lot of research on the subject and is very apocalyptic about it all. a lot of people also dismiss him, saying that he is not a good scientist and exaggerates too much and whatnot. if he's a hack, what exactly has he done that warrants such ... | url, climate, claims ====== he's not a hack. he's one of the most respected climate scientists in the field. he's well published, and has [contributed tremendously to the field](_url_3_). the "hack" claims come from many sides. he's become very outspoken, so much so that his public persona has taken off his research sc... | 12 | [] | [] | [
"http://www.bloomberg.com/news/2011-08-29/nasa-s-hansen-arrested-outside-white-house-at-pipeline-protest.html",
"350.org",
"http://www.amazon.com/Storms-My-Grandchildren-Catastrophe-Humanity/dp/1608192008",
"http://en.wikipedia.org/wiki/James_Hansen#Research_and_publications",
"www.350.org"
] | [
-1.6460411548614502,
2.5077896118164062,
-1.8542227745056152,
1.3575032949447632,
1.5271233320236206,
-0.7084415555000305,
0.03215716779232025,
-0.605831503868103,
-1.2352495193481445,
-0.8889476656913757,
-0.5665251612663269,
-1.8123385906219482,
0.31626254320144653,
2.8390955924987793,
... |
concerning the neutrino experiment: how exactly does this relate back to the idea of time travel? | i've seen/heard people talk about the possibility of time travel in such a context, but only in layman's terms... "it breaks einstein's laws, which means time travel is possible" sort of statements. does anyone here have the qualification to actually explain the reason in an articulate and reasonably understandable man... | make any sense, revisit this question, light ====== none of these comments/answers (whatever you may call them) make any sense, and i would hope someone would revisit this question. the two answers below are based on the idea that faster than light travel equals negative time, when in fact time is still constant. the s... | 2 | [] | [] | [] | [
-1.1856513023376465,
-1.511905312538147,
0.09470448642969131,
1.4260504245758057,
-1.210039496421814,
-2.1263813972473145,
-1.9763996601104736,
-0.28040647506713867,
1.5669894218444824,
-1.506441354751587,
0.4231775104999542,
0.03081279993057251,
-0.6747556924819946,
0.06903098523616791,
... |
how rare is it for a death to occur from picking at pimples on the death pyramid? | exactly what the title says. i'm talking about [this](_url_0_). | url, pretty rare, infection ====== pretty rare. the "danger" in this area is usually due to the possibility of intense oral infections (periradicular from tooth decay - an abscess), to travel up the veins (since veins can have 2 way transport), into the [cavernous sinus](_url_2_), and cause an infection in your brain. ... | 10 | [] | [
"http://en.wikipedia.org/wiki/Danger_triangle_of_the_face"
] | [
"http://history.amedd.army.mil/booksdocs/wwii/thoracicsurgeryvolii/chapter1figure7.jpg",
"http://en.wikipedia.org/wiki/Ludwig's_angina",
"http://en.wikipedia.org/wiki/Cavernous_sinus",
"http://www.doctorspiller.com/cavernoussinus.htm",
"http://en.wikipedia.org/wiki/Pterygoid_venous_plexus"
] | [
-2.1622724533081055,
-0.5105369091033936,
-0.3254026174545288,
-0.48012101650238037,
-1.834054946899414,
-1.5432016849517822,
1.0912775993347168,
1.0462747812271118,
1.5319682359695435,
-0.09384003281593323,
1.5145686864852905,
-0.9614508748054504,
0.24134907126426697,
0.9346417784690857,
... |
how do flood and storm measurements (eg. 25-year flood, 100-year storm, etc) relate to the gambler's fallacy? | fallacy simply describes, year, year flood ====== the gamblers fallacy simply describes the belief that if, let's say, a 100 year flood happens one year, it is less likely to happen again the next year. flood measurements are based on historic data, and simply estimate the average recurrance time of events on that part... | 6 | [] | [] | [] | [
-0.4218609035015106,
0.03150642663240433,
1.593597173690796,
0.6225776672363281,
2.192077875137329,
-0.02041575312614441,
-0.9854183793067932,
-0.2555598318576813,
1.3585458993911743,
-1.0609405040740967,
-0.7427825927734375,
-0.42789313197135925,
0.05268418788909912,
0.22545307874679565,
... | |
what is this mystery "mold" that has appeared in my yard? | this mold (or whatever) is growing on a small (2 foot) japanese maple we have on our back deck. [close-up pic.](_url_2_) [bit zoomed out.](_url_1_) [further out.](_url_0_) i haven't seen it prior to this year. i've actually seen it elsewhere around the yard as well, and again, don't think i've seen it before this year,... | ochrolechia, wrong, url ====== this appears to be one of the *ochrolechia* lichens, although i could be wrong. check out the photos at [e-flora bc](_url_0_), though, and see what you think. in any case, it's definitely a lichen, and harmless to your tree. you must have had just the right weather conditions for it to gr... | 5 | [] | [
"http://i.imgur.com/5cURG.jpg",
"http://i.imgur.com/9x7Gk.jpg",
"http://i.imgur.com/BvMtC.jpg"
] | [
"http://linnet.geog.ubc.ca/DB_Query/QueryForm.aspx?__VIEWSTATE=%2FwEPDwUJNDMxMjI1OTg5ZBgBBR5fX0NvbnRyb2xzUmVxdWlyZVBvc3RCYWNrS2V5X18WAwUIY2hrRXhhY3QFCGNoa1RodW1iBQhjaGtBdGxhc4Yxo9PWBfrzxL%2Fstl1UphBzyo2o&__EVENTVALIDATION=%2FwEWIgK8nOiyBQLNsNusBAKh4d%2F2BAKVidf0BQLp%2BML9CwK8t5zWAQKgrLiVDgKptpXRDQLU6PSQDAKJgc%2... | [
-0.6903141736984253,
1.0721379518508911,
-0.12243787944316864,
1.2738127708435059,
1.2154628038406372,
-0.2920994162559509,
-0.07681755721569061,
-0.021416902542114258,
-0.37384384870529175,
-0.1740313470363617,
-0.4273785352706909,
-0.10833689570426941,
0.1860436648130417,
0.3859974145889... |
what is the chemistry behind "snapz?" | as a child, i was able to purchase the "snapz" which, for those who are unaware, seemingly resemble gravel wrapped in tissue paper that produces an audible "pop" and smoke upon impact with a hard surface. i would like to know the chemistry behind this marvel i enjoyed as a child. thanks for the help redditors. | wrapped in tissue, tissue paper, compound called silver ====== these look like gravel (or sand) wrapped in tissue paper, because that's what they mostly are. but theres a small amount of a compound called silver fulminate dried in with it. the fulminate salts are invariably shock-sensitive. there's a lot of energy stac... | 9 | [] | [] | [
"http://en.wikipedia.org/wiki/Bang_snaps",
"http://en.wikipedia.org/wiki/Silver_fulminate"
] | [
-1.8247871398925781,
0.40644320845603943,
0.8397562503814697,
-0.07443387061357498,
0.9003456234931946,
-1.2377007007598877,
2.166916608810425,
0.9791263937950134,
1.4350981712341309,
-0.13345664739608765,
-0.49746066331863403,
0.4479171931743622,
0.509750247001648,
-0.7009567618370056,
... |
is there such a thing as a perfect hermetic seal and/or a material which is completely impermeable? if not, is such a thing even theoretically possible? | basically, what i am asking is if there is anything which can perfectly contain fluids, in particular hydrogen and helium, without any leakage. as i understand it, even metal flasks have trouble with this, due to the hydrogen seaping through. moreover, this seems to especially be a problem with helium since it is monoa... | tricky word, perfect, word ====== "perfect" is a tricky word. no container is going to give you zero losses over an indefinite period of time (if nothing else your container will eventually evaporate). as a practical matter, you have to define acceptable losses per unit time. | 2 | [] | [] | [] | [
-0.2342781126499176,
0.2890089154243469,
0.0969153344631195,
-0.2754523754119873,
-0.07576917111873627,
0.17633511126041412,
0.107631616294384,
0.4465267062187195,
0.2896626591682434,
0.29806455969810486,
0.08323969691991806,
0.47127020359039307,
0.3603140711784363,
-0.0692458227276802,
... |
how the hell do cicada nymphs count to 17? | there's a large brood of 17-year cicadas emerging in my hometown right now (i know that 13-year periodical cicadas exist too). i have a reasonable understanding of the life cycle, but have never read anything about what on earth the mechanism is by which the cicada "counts" (as count it must) the passing of years. my u... | time richard karban, weinbaum ecology letters, evolutionary strategy paulo ====== read: how 17 year cicadas keep track of time richard karban, carrie a. black and steven a. weinbaum ecology letters, (2000) q : 253±256 _url_0_ and emergence of prime numbers as the result of evolutionary strategy paulo r. a. campos, vivi... | 7 | [] | [] | [
"http://onlinelibrary.wiley.com/doi/10.1046/j.1461-0248.2000.00164.x/abstract",
"http://www.cicadamania.com/downloads/prime-PRL.pdf"
] | [
-0.12158671021461487,
0.12494505941867828,
-0.09505530446767807,
-0.23401662707328796,
-0.48839154839515686,
0.6217379570007324,
0.22352802753448486,
0.5816332697868347,
0.6902923583984375,
0.21833257377147675,
1.024990439414978,
-1.314004898071289,
-0.4052511155605316,
0.33421218395233154... |
psychology question | (i'd put the actual question in the title if i it'd actually fit) i heard somewhere that it makes it easy to focus on work if you do working/studying stuff in one spot, and leisure activities in a separate spot. it's one of those things that "everyone knows", but correct me if i'm wrong on that. would the above apply i... | natively makes connections, mind natively makes, mind natively ====== your mind natively makes connections between things. it's part of what let's us learn and adapt and be successful as a species. if you do the same things in the same places, over and over, then your mind begins to "jump" to those modes that you do in... | 3 | [] | [] | [] | [
2.369187831878662,
-0.6081839203834534,
0.9219127893447876,
-0.9655922651290894,
0.12273219227790833,
-0.09292544424533844,
-0.45822399854660034,
-1.252648949623108,
1.2577879428863525,
0.6796882152557373,
1.1474887132644653,
2.756101608276367,
-0.6329516768455505,
0.13217078149318695,
1... |
can some one explain synaptic pruning to me? | i've gone to other places to look for answers but none of it is making much sense. | neurons at birth, arise through neurogenesis, connection ====== not sure how much detail you want, but briefly, we start out with tons of connections in between neurons at birth, which arise through neurogenesis. then what happens is the connections start "dying off." if connection a, for example, is used a ton, but co... | 9 | [] | [] | [] | [
0.1091926097869873,
-0.13756781816482544,
0.5622329711914062,
-0.2735982835292816,
-1.0655745267868042,
0.0049762725830078125,
0.6176137924194336,
0.8709430694580078,
1.1453030109405518,
-0.12129268050193787,
0.3922531008720398,
0.7703402638435364,
-0.4015428423881531,
-0.2341982126235962,... |
what do the presenters of this video mean when they talk about the suspended silicon ball acting like a quantum object? | _url_0_ i don't quite understand how what they showed is a representation of the double slit experiment, i just see the particles behaving as particles while the waves being made by the bouncing drops behave like waves. | video is pure, pure, entertaining ====== this video is pure (though entertaining) fluff until the last 15 seconds or so, let's quote: and that's all you need to know. the *reason* they were saying that some of the properties were similar is because you have localized waves which can interfere or diffract like a quantum... | 6 | [] | [
"https://www.youtube.com/watch?v=sGCtMKthRh4"
] | [
"https://www.youtube.com/watch?v=TSeLufEdng4"
] | [
-0.8194739818572998,
-0.6535556316375732,
0.15580976009368896,
-0.3442270755767822,
0.23631754517555237,
-0.5325618982315063,
0.674111008644104,
-0.04427144676446915,
0.27649974822998047,
-0.27652931213378906,
0.5199306607246399,
-0.21741053462028503,
-0.09990492463111877,
0.62774509191513... |
what is the hard evidence for the economic benefits of science? (more detail in comments) | i am aware of the example of the space race, and that every dollar spent on it gave 7 dollars in return (paraphrasing). but have there been any articles or research papers quantifying that science = economic prosperity. i can find plenty of editorials and opinions but no facts. anything would be great as it is an area ... | direction and funding, cost benefit analysis, cost benefit ====== sometimes companies do a cost benefit analysis for the direction and funding of their r & d department. for instance natural products chemistry was a a division of every major pharmaceutical company until the 90s. at that point they realized that they co... | 3 | [] | [] | [] | [
-1.4323517084121704,
-1.1476393938064575,
-0.59978187084198,
-0.6572833061218262,
0.15359899401664734,
0.031649112701416016,
0.04595625400543213,
1.2971423864364624,
0.281070739030838,
-0.2153201848268509,
0.4549576938152313,
1.1896580457687378,
0.37064045667648315,
1.5019131898880005,
0... |
how could i "timestamp" a physical letter such that later on i can prove it was created at a certain date? | i've heard of carbon dating, but that's for longer periods of time. is there a way to create something physical that can later be tested to give an exact date? example: i write a letter that outlines my method of extracting an amazing source of power. however, i don't want it to be used as a bomb. i write down my notes... | regular post, send, post ====== send it to yourself via regular post. the postmark will indicate the date. note that this will not protect your idea though. patents rights are granted on a first to file basis, rather than first to invent. the only way to invalidate a competitor's patent is to prove that the information... | 5 | [] | [] | [
"https://proofofexistence.com/"
] | [
-1.4799736738204956,
-0.13574987649917603,
-0.7730038166046143,
-0.7035468816757202,
0.28707388043403625,
0.3894909620285034,
-0.9198095798492432,
-0.051271580159664154,
-0.2320268750190735,
-0.3278202712535858,
0.47539663314819336,
0.9560391306877136,
0.002222508192062378,
-0.345654278993... |
why don't we know everything, just by looking at the fundamental laws? | thanks for reading my question :) i've always wondered why we can't just make a computer simulation which strictly follows the most basic laws of physics and from there tell everything. why is it necessary to derive special-case laws? take electromagnetism for example: as far as i've been told at my uni-course, the fou... | extremely costly computer, extremely costly, algorithms that work ====== because it would be extremely costly computer simulations, and we might not even have algorithms that work well enough to do all we want to do. for example, going from atoms to macroscopic systems is incredibly hard. even with an approximate descr... | 20 | [] | [] | [
"https://en.wikipedia.org/wiki/Orders_of_magnitude_(data)"
] | [
-6.5358195304870605,
0.43717360496520996,
-0.32293954491615295,
-1.7607336044311523,
0.17985910177230835,
-2.3962337970733643,
-3.3622870445251465,
2.29190993309021,
3.7250242233276367,
-1.459989309310913,
4.444794654846191,
1.9711992740631104,
-0.37513267993927,
0.6596933007240295,
2.00... |
help me solve the mystery of the melting mason? | [removed] | jar, style jar, attract unlike-jars ====== i don't think it is possible. as anyone who has had more than one "mason" style jar in the kitchen, they seem to attract unlike-jars. so even if you think that you got all your jars at the same time, you indeed have three or four different sizes, two different brands, and one ... | 4 | [] | [] | [] | [
-0.15766143798828125,
-0.3867100477218628,
-1.0506279468536377,
-0.22982564568519592,
-0.7090492248535156,
-2.6022937297821045,
1.4440581798553467,
-0.7932632565498352,
0.35856205224990845,
-1.6221123933792114,
0.48357462882995605,
0.3318500816822052,
-1.189922571182251,
-0.040162838995456... |
what would geomagnetic reversal mean for modern society as we know it? | if geomagnetic reversal were to occur what would happen? what would it affect and what would the effects be? if damage were to occur what would it take to fix it? | slow event, typically taking, millennium to occur ====== a geomagnetic reversal is a very slow event, typically taking over a millennium to occur. there would be some required sorting out of things related to compasses and direction-finding, but we would have hundreds, thousands, or even tens of thousands of years to f... | 3 | [] | [] | [
"http://www.reddit.com/r/askscience/comments/vwgwe/how_much_damage_would_a_sudden_reversal_of_the/",
"http://www.reddit.com/r/askscience/comments/on96z/consequences_of_geomagnetic_reversal/"
] | [
-0.3212790787220001,
-0.13982407748699188,
0.6149652600288391,
-0.5028200149536133,
-0.1492350548505783,
-0.5385857224464417,
0.05513733625411987,
-0.6458273530006409,
0.7491536140441895,
0.17646783590316772,
0.3077220618724823,
1.3741923570632935,
0.9909581542015076,
0.38569390773773193,
... |
if you die while intoxicated, does your bal stay the same (since it's not being metabolized anymore)? | just watched a video of a guy live streaming while driving extremely drunk. wondered if he died, would you want to get a blood sample immediately, or could it wait until he gets to the morgue. | complicated thing, url, death ====== death while intoxicated is a complicated thing. according to [this](_url_0_), blood alcohol concentration (bac) after death may increase due to fermentation processes from microorganisms or from the continued diffusion of residual alcohol in the stomach. [this](_url_1_) is a powerpo... | 5 | [] | [] | [
"https://www.ncbi.nlm.nih.gov/pubmed/16782292",
"http://www.cal-tox.org/Downloads/proceedings/0503/catsatmay2003_fri_jones.pdf"
] | [
-0.6197494864463806,
0.4914478361606598,
-0.6886661052703857,
0.39154279232025146,
0.8472733497619629,
0.7279302477836609,
1.1033859252929688,
1.0491746664047241,
-0.262461394071579,
-0.6264610886573792,
0.04723595082759857,
-1.3442203998565674,
-0.29325538873672485,
0.06716254353523254,
... |
following from the 700tb stored in a gram discovery, how long would it take to actually sequence that out. | didn't say in the [article](_url_0_), but what would the theoretical read-speed be on that (to sequence it all out) i'm no scientist but if i remember freshmen bio, sequencing takes a very long time, and i thought a gram of dna is a lot. | days, sequence, dna ====== yes a gram of dna is a lot. when you sequence dna you're usually starting with less than 1 ug (microgram), so less than 1 millionth of a gram. 700 terabytes = 5600 terabits, so that's 5600 terabases of dna. the highest throughput dna sequencing machine is, i'm pretty sure, the [illumina hiseq... | 10 | [] | [
"http://www.extremetech.com/extreme/134672-harvard-cracks-dna-storage-crams-700-terabytes-of-data-into-a-single-gram"
] | [
"http://en.wikipedia.org/wiki/Beijing_Genomics_Institute",
"http://www.illumina.com/systems/hiseq_systems.ilmn",
"http://professional.wsj.com/article/SB10000872396390444233104577593291643488120.html",
"http://www.sciencemag.org/content/suppl/2012/08/15/science.1226355.DC1/Church.SM.pdf"
] | [
-2.638587474822998,
0.27573543787002563,
-1.6046446561813354,
-2.2073404788970947,
-5.1626458168029785,
-2.9277944564819336,
-4.624373912811279,
1.0177817344665527,
0.2046610713005066,
-0.4726506173610687,
0.4043683409690857,
0.22523579001426697,
0.18718895316123962,
0.18806324899196625,
... |
deformation of a copper brick | imagine a brick made out of solid copper. the brick would, really, be made out of copper atoms, with nuclei being repelled from each other and electrons roaming randomly. now, look at the very edge of the brick. the copper nuclei at the very edge are being repelled by nuclei further into the brick, but are not being re... | hmm, surface, idealized brick ====== hmm.... well, if you look at this idealized brick, you will often find that the surface atoms do in fact rearrange themselves so that they are arranged differently than those in the bulk. this is called a surface reconstruction. the atoms near the surface will also slightly deform t... | 4 | [] | [] | [] | [
-0.9227497577667236,
0.36770930886268616,
0.6851754188537598,
0.2330203503370285,
0.25483882427215576,
-1.0521667003631592,
0.09303554892539978,
-0.3177475929260254,
0.1645786464214325,
-0.5044317841529846,
0.28230613470077515,
0.7575383186340332,
-0.2727319598197937,
-0.02339840680360794,... |
does delaying gratification on purpose have any measurable effects on a person? | i'm curious if there has been any research related to the effects of purposely delaying gratification for an extended period of time. all of my searching has found plenty of research on the correlations between the ability to delay gratification and other factors such as self control, academic success, likelihood to us... | delay gratification, vast majority, generally assessing ====== you are right, the vast majority of studies look at the differences/long term effects of people who can delay gratification vs. those who can't, and generally assessing a person's self-control. studies which show what effect, if any, training a person to de... | 2 | [] | [] | [] | [
-0.39417198300361633,
-0.23801827430725098,
0.7621015906333923,
-1.5510472059249878,
-1.4100145101547241,
0.7429162263870239,
0.5023434162139893,
-0.051729269325733185,
-0.8684711456298828,
0.5044538378715515,
2.613544464111328,
2.680293560028076,
0.6898713111877441,
0.8377443552017212,
... |
concerning the "first world problem" meme, how can it be -173c at night on mercury and only 0c where i live at night? | as the title suggests, i was curious how it can be so cold on a planet so close to the sun. is it the lack of atmosphere? anyways, any explanation would be greatly appreciated! | earth days long, mercury night, earth days ====== it's a combination of the lack of atmosphere and the fact that [mercury's night is almost 30 earth days long](_url_0_); that gives it a lot of time to cool off after the hot day. | 10 | [] | [] | [
"https://www.google.com/search?q=length+of+day+mercury"
] | [
0.31878402829170227,
0.5124232769012451,
0.7521750330924988,
0.9938415288925171,
0.4297904670238495,
-0.649645984172821,
0.20014896988868713,
-0.6279793977737427,
0.01375243067741394,
-0.4144679307937622,
-0.2399064302444458,
-0.34864819049835205,
-0.12552571296691895,
0.1195564866065979,
... |
why is the uniformity of the cmb seen as an anomaly? | i've read that one of the reasons we think inflation happened is because of the uniformity of the cosmic microwave backround. the idea (i think) is that unless everything had time to 'mix' and become the same temperature we would see larger fluctuations in the cmb. an example of this is here, _url_0_ , where they use a... | fine tuning, main rationales, url ====== i will say that there's other support for inflation but one of the main rationales is that inflation solves many [problems](_url_2_) of ["fine tuning"](_url_1_) of the initial conditions of the universe. the [flatness problem](_url_0_) is an even better example of fine tuning so... | 6 | [] | [
"http://cosmictimes.gsfc.nasa.gov/online_edition/1993Cosmic/inflation.html"
] | [
"https://en.wikipedia.org/wiki/Flatness_problem#Current_value_of_.CE.A9",
"https://en.wikipedia.org/wiki/Fine-tuning",
"https://en.wikipedia.org/wiki/Inflation_(cosmology\\)#Motivations"
] | [
-2.0812649726867676,
0.7389639019966125,
2.199460506439209,
2.285750150680542,
2.6881773471832275,
-1.747452974319458,
-2.237562417984009,
0.12098096311092377,
1.6330004930496216,
-2.4269323348999023,
-0.8284147381782532,
0.618018627166748,
0.5773372054100037,
0.20351286232471466,
3.5603... |
how does something like this form naturally? | _url_0_ it just seems like such a major coincidence. how does such a huge boulder come to rest on a spot like that and stay balanced? | side boulders, fell off making, possibly settled ====== in addition to what esbenab said, think about this: there are many *many* more boulders that did not manage to come to rest like this one (and just fell off making two side by side boulders), but we don't really take that into consideration when we think about how... | 16 | [] | [
"http://imgur.com/8N7vk"
] | [
"http://en.wikipedia.org/wiki/Confirmation_bias"
] | [
0.5620182752609253,
-0.04016387090086937,
0.3885212242603302,
0.6265654563903809,
1.1179124116897583,
-1.4363681077957153,
-0.0565367266535759,
-0.3651233911514282,
0.9425039291381836,
-1.0278147459030151,
1.0148870944976807,
0.8092183470726013,
0.7460309267044067,
-0.2624284327030182,
1... |
a physics puzzle | on the floor of an elevator/lift are a blob of mercury and a lit candle in a holder. the cable snaps. what happens? (assuming the the lift shaft to be very long or infinite.) | minimize surface energy, blob of mercury, surface energy ====== blob of mercury: the blob of mercury will, to minimize surface energy, become a sphere. the motion from changing shape will impart momentum to the sphere, and it will drift upwards from the floor. candle: the flame will die. since the air is accelerating w... | 12 | [] | [] | [] | [
-0.7912719249725342,
1.9229230880737305,
0.7616555094718933,
0.8497744798660278,
-0.29258620738983154,
0.08497923612594604,
1.073319673538208,
-0.006231561303138733,
0.8469969630241394,
0.03117884323000908,
0.2787005305290222,
0.04060259461402893,
-0.7133148908615112,
-0.38786110281944275,... |
what stopped the black plaque? (x-post from /r/askhistorians) | we've all learned about the black plague in high school, but no one ever taught us what stopped it or why it stopped, just that it happened. anyone know this? -- /u/mrsocialclub i found this an interesting question; i would love to know more too :p | pandemics typically evolve, hosts too quickly, typically evolve ====== pandemics typically evolve to be less virulent because they kill their hosts too quickly. this article tells it for the layman and contains links to the original research. _url_0_ | 8 | [] | [] | [
"http://www.forbes.com/sites/stevensalzberg/2011/09/02/the-black-death-is-dead-thanks-to-evolution/"
] | [
-0.9690672755241394,
-0.319877028465271,
0.09315323829650879,
0.23853978514671326,
0.30887818336486816,
-0.15446346998214722,
-0.35843977332115173,
0.16357162594795227,
0.41034841537475586,
-0.10239381343126297,
-0.1595025658607483,
0.3790452480316162,
0.11553728580474854,
0.05688454210758... |
would a d.c supply and an a.c supply of the same quoted value supply the same power to a given resistor? | [deleted] | long-term average, depends, quoted ====== depends on how the value is quoted. if the value is rms voltage, then yes (long-term average), since the power dissipated in the resistor is proportional to v^2 . if it's peak voltage, then no. | 14 | [] | [] | [] | [
-0.5685454607009888,
0.6516027450561523,
-0.19210243225097656,
0.032106272876262665,
-0.44618403911590576,
0.20986655354499817,
-0.4568370282649994,
1.170122504234314,
0.4456835985183716,
0.24823349714279175,
0.6529492139816284,
-0.4295298755168915,
0.27133262157440186,
0.01533589884638786... |
from an evolutionary standpoint, what's in store for humans in the distant future? | future generations, prevalent in future, traits that lead ====== if you think about the mechanism behind evolution, traits that lead to more offspring will be more prevalent in future generations. while these traits used to be survival focused, in modern time it has been largely social, and dependent on a huge variety ... | 3 | [] | [] | [] | [
0.046136945486068726,
0.09456038475036621,
0.1639561802148819,
-0.22191500663757324,
0.2450789213180542,
0.1467013955116272,
-1.5113413333892822,
0.1778339445590973,
1.0670949220657349,
-0.004049837589263916,
1.6838712692260742,
0.39206984639167786,
-0.5999830961227417,
0.661194920539856,
... | |
which nerve supplies the diaphragm with autonomic innervation ? | phrenic nerve (c3-c5) supplies the diphragm with somatic innervation, where does autonomic innervation come from? and where does the preganglionic nerve and the postganglionic synapse ? | skeletal muscle, autonomic innervation, supplied with autonomic ====== diaphragm is a skeletal muscle, so it is not supplied with autonomic innervation. breathing is an antonomous process that can be hijacked by higher nervous centers, but all signals come only via phrenic nerve. in the brainstem there is a respiratory... | 2 | [] | [] | [] | [
-0.5697596073150635,
0.14157065749168396,
0.818972110748291,
1.3872480392456055,
-0.45312801003456116,
-0.4358922243118286,
2.7961597442626953,
0.6697152256965637,
2.076082706451416,
0.7983337640762329,
1.4764714241027832,
0.12635020911693573,
-0.7302150726318359,
0.07093057036399841,
0.... |
i think there may be an endangered crayfish species living in my neighborhood creek - what should i do? how do i get my son involved? | my son has spent a lot of time at our neighborhood creek over the last 5 years, and knows it like the back of his hand. the hubby was poking around on the internet and found out that there is an [endangered crayfish](_url_0_) that lives in the general area of our house. from the best we can tell (without removing the c... | graduate students, find an endangered, endangered specie ====== your university probably has graduate students who would love to find an endangered specie in the backyard. biology and environmental science departments would be the right place to start. your state or province environmental agency may be able to help. as... | 7 | [] | [
"http://en.wikipedia.org/wiki/Orconectes_shoupi"
] | [] | [
-0.02035420760512352,
-0.1287127286195755,
1.1698980331420898,
0.12075361609458923,
0.5792160034179688,
-0.97761470079422,
-0.8251688480377197,
-0.010241318494081497,
-1.587032675743103,
0.5115088820457458,
0.15563179552555084,
-1.4314391613006592,
-0.7137637734413147,
1.2685648202896118,
... |
is it possible to "overstretch" before exercising? | sometimes i feel less strong when i do a thorough, deep 10 minute stretch before lifting weights. i feel more strong when i warm up and get my blood flowing with some cardio then do a quick 30 second stretch before using a muscle group. should you be as limber as possible before lifting weights or can this cause injury... | reduce strains, lots of safety, safety meetings ====== we've had lots of safety meetings about stretching before work to reduce strains/sprains. we've had guys actually come in and teach us how to do it properly because for every injury the comp rate increases thus making it harder for the company to get jobs they bid.... | 2 | [] | [] | [] | [
-0.546640157699585,
0.06469026207923889,
0.24821901321411133,
-1.4798345565795898,
-1.3969858884811401,
0.017431646585464478,
-0.5948277711868286,
1.0508363246917725,
-0.12557518482208252,
0.031352587044239044,
0.7523725032806396,
1.1891047954559326,
0.06671646237373352,
0.7215943932533264... |
the stanford cooling glove: so what's the rub? | i've seen articles about [this apparatus](_url_0_) that helps you exercise by cooling your core much quicker. it sounds to good to be true, but i haven't heard the rub. do people over do it? is it too expensive? why the heck isn't this thing in every gym in america by now? | scientifically rigorous, naturally less scientifically, time ago ====== well, this was discussed in /r/skeptic some time ago but the conversation there is naturally less scientifically rigorous. sadly i did not save the thread. regardless, the issues tend to clump around two essential questions. for one we have: does r... | 2 | [] | [
"http://news.stanford.edu/news/2012/august/cooling-glove-research-082912.html"
] | [] | [
-2.698026657104492,
1.4857913255691528,
1.5399221181869507,
2.22139048576355,
0.025178804993629456,
-1.6010324954986572,
-1.7935172319412231,
0.687271773815155,
-1.4176095724105835,
0.1127949133515358,
0.5221244096755981,
1.7199393510818481,
-0.7134844064712524,
1.0171186923980713,
1.075... |
what is air resistance and why does it affect materials like it does? | so i was thinking about water and the strength of its polar bond like any normal person would on a relaxing evening... ...when i considered that water, when dropped from a height, more or less turns into a mist. that is, the air resistance is overcoming the strength of water's strong attraction to itself and breaking i... | surface tension, surface area, surface ====== the specific phenomenon you are referring to - water breaking up into droplets - is due to the surface tension of the water and in fluid mechanics is called the [plateau-rayleigh instability](_url_0_) (youtube video [here](_url_1_) as well). basically what happens is that d... | 3 | [] | [] | [
"http://en.wikipedia.org/wiki/Plateau%E2%80%93Rayleigh_instability",
"http://youtu.be/ml4KEy4N0gc"
] | [
-2.9947266578674316,
-2.2730748653411865,
3.129866123199463,
-0.10703498125076294,
0.2574551999568939,
-4.753915309906006,
3.8567166328430176,
2.2990520000457764,
-0.508230447769165,
0.43671566247940063,
0.5808871984481812,
0.6909896731376648,
0.6853316426277161,
4.409188270568848,
1.318... |
few questions about this space walk photograph. | _url_0_ this was on the front page earlier and i have a few questions about it. is it possible to calculate how fast the astronaut would be orbiting the earth? also how does he stay close to the shuttle so that he can return safely, i.e is he orbiting at the same speed and can therefore stay next to it? and finally if ... | newton constant times, earth divided, velocity needed ====== the velocity needed to remain in orbit is equal to the square root of newton's constant times the mass of earth divided by the distance from the center of the earth. i don't know the altitude of that specific mission, but they're usually around 300 km. that m... | 6 | [] | [
"http://apod.nasa.gov/apod/image/1201/freeflyer_nasa_3000.jpg"
] | [] | [
1.358088493347168,
0.7021467685699463,
0.6112713813781738,
0.35564544796943665,
-0.2842552661895752,
-0.5253794193267822,
0.2470584660768509,
0.7323986291885376,
0.6366191506385803,
-0.6645205020904541,
0.9964243173599243,
-0.2884058356285095,
0.37287652492523193,
0.14373497664928436,
0.... |
captain planet question here: earth vs water vs wind vs fire -- which wins? | i hope i ask this question as sensibly as possible, but it was the old cartoon that spawned my curiosity. in a battle of the most solid matter, vs a massive amount of water, vs the hottest flames (or gases?), vs the strongest wind, which is the most powerful? additionally, please give the most upvotes to the person who... | wind, water, earth ====== fire can't exist without wind. water is ice in space without earth. wind, overtime, erodes earth. fire turns water into vapor. wind can cause waves with water, but you need earth with sufficient gravitational pull to have water that can be affected by wind. basically, they all need each other ... | 2 | [] | [] | [] | [
-0.0013005733489990234,
0.5675122737884521,
0.6085677146911621,
0.5815924406051636,
1.2623257637023926,
-0.46189242601394653,
0.2388906329870224,
-0.24799351394176483,
-0.1527256965637207,
-0.5133452415466309,
-0.05814807116985321,
-0.3554152846336365,
-0.4182877540588379,
0.21622411906719... |
video lectures/books/tutorials for learning basic physics | at last thought of learning physics again after i left school 5 years. the urge is due to the fact that i still couldn't get the science behind the stuff like pressure, light... though i know the theory, but couldn't relate to it in practical aspects. as a compsci grad, i badly need greater understanding of physics. so... | url, khan academy, physics ====== the [khan academy](_url_5_) is an excellent resource for introductory material. if you've got a fairly solid understanding of basic calculus, you might also like leonard susskind's modern physics series, which is a six-quarter survey sequence: 1. [classical mechanics](_url_7_) 2. [quan... | 2 | [] | [] | [
"http://www.cosmolearning.com/courses/modern-physics-general-relativity/",
"http://www.theassayer.org/cgi-bin/asbrowsesubject.cgi?class=Q#freeclassQC",
"http://ocw.mit.edu/courses/physics/",
"http://www.cosmolearning.com/courses/modern-physics-cosmology/",
"http://www.cosmolearning.com/courses/particle-phys... | [
-2.991818904876709,
0.5859220623970032,
-0.12939009070396423,
0.44061729311943054,
-0.9173471927642822,
1.0791279077529907,
-0.6621345281600952,
0.6205455660820007,
0.46048152446746826,
-1.5669031143188477,
0.29888981580734253,
0.2714318037033081,
0.343485951423645,
1.5763444900512695,
-... |
high school level physics experiments | i love doing physics experiments at home, but there aren't many good ones on the internet. so, what are some high school level physics experiments you can do at home? | home experiments, crawford book, berkeley series ====== crawford's book *waves* (volume 3 of the berkeley series), while a college text, has a whole collection of "home experiments" throughout it. i can't recall how much they depend on your having gone through the material in his book, and how much they'd just be inter... | 3 | [] | [] | [
"http://van.physics.illinois.edu/qa/listing.php?id=819",
"http://van.physics.illinois.edu/qa/listing.php?id=818"
] | [
-0.25767117738723755,
-0.4212796688079834,
-0.37756770849227905,
-0.35320478677749634,
-0.5541621446609497,
0.21271547675132751,
0.07494238764047623,
0.35504525899887085,
0.27605360746383667,
-0.616254985332489,
-0.6374075412750244,
0.10465867817401886,
0.1793057769536972,
-0.0103298565372... |
which came first, the receptor or the ligand? | from what i understand, ligands exert their physiological effects typically through receptors, proteins made up of hundreds of amino acids. how could, say, serotonin, act on tissues if the tissue has no receptors for serotonin? what would be the selective pressure to keep serotonin around even though it has no receptor... | egg riddle, fun twist, correct answer ====== ooh, a fun twist on the chicken/egg riddle (to which there is a correct answer, btw)! short answer: no one knows for sure, but probably the receptor. longer answer: multi-part molecular machines are a defining feature of metazoan biology. it has always been hard, however, to... | 3 | [] | [] | [] | [
-5.111843585968018,
-1.3154879808425903,
-2.0921497344970703,
-1.2273118495941162,
-1.1465734243392944,
-1.1711238622665405,
1.972447156906128,
0.27038252353668213,
2.632887601852417,
-1.4178143739700317,
3.283921718597412,
1.0920237302780151,
-0.5919395685195923,
0.16051426529884338,
0.... |
quality of journal physics letters | to physicists on reddit, or anybody who has critically read or submitted articles published in the series of journals physic letters x. what is your experience and how would you describe the quality and rigor of the published work? thanks for your input! | journal, strong opinion, top journals ====== i've only read it. no strong opinion really. afaik, it's just another second or third-tier journal. which isn't really a judgment on the quality or reliability of the results published as much as it's about their overall significance. i think most scientists would agree that... | 3 | [] | [] | [
"http://www.elsevier.com/wps/find/journaldescription.cws_home/505706/description",
"http://en.wikipedia.org/wiki/Impact_factor",
"http://www.elsevier.com/wps/find/journaldescription.cws_home/505705/description"
] | [
-5.343389987945557,
-2.875535011291504,
-3.301398515701294,
-0.7792004942893982,
0.9933950304985046,
-1.1088402271270752,
-3.221283435821533,
2.393427848815918,
3.675614356994629,
-0.06513538211584091,
2.6000869274139404,
2.1694576740264893,
0.8689233064651489,
0.3834879994392395,
-0.837... |
askscience: i am not conversant enough in physics to understand the recent abstracts from atlas and cms. can you help translate these into non-technical terms? | i have a chemistry background, so i have taken physics for scientists and engineers, thermodynamics, and quantum mechanics. however, none of this covered standard model or any particle physics, or any of the notations used by these guys. from my gcms experience, i am guessing that "integrated luminosities" refers to th... | part is clear, april to june, decay ====== here's a sentence-by-sentence explanation of the atlas abstract: hopefully that part is clear ;-) this is saying that they are using both the 2011 run of the lhc and the 2012 run which lasted from this past april to june. for the 2011 run, the protons were collided at a speed ... | 4 | [] | [
"http://arxiv.org/abs/1207.7235",
"http://arxiv.org/abs/1207.7214"
] | [
"http://physics.stackexchange.com/questions/12059/what-is-an-inverse-femto-barn"
] | [
-7.9699482917785645,
-0.47835642099380493,
1.1585056781768799,
2.6263768672943115,
-3.5117409229278564,
-3.6175713539123535,
-1.0330168008804321,
2.561143398284912,
4.417665958404541,
-1.9000388383865356,
2.5897841453552246,
-0.6031646728515625,
1.4321045875549316,
-4.666889190673828,
-1... |
what is the energy cost of thought? | answered with google, david a. levitsky, cornell university ====== this question is easily answered with google: _url_0_ this article is from the new york times, and contains a quote from david a. levitsky, a professor of nutrition and psychology at cornell university. he is paraphrased as saying that were a person to ... | 3 | [] | [] | [
"http://www.nytimes.com/2008/09/02/science/02qna.html"
] | [
-0.650031566619873,
-0.43212759494781494,
0.04490207880735397,
1.0671653747558594,
-1.11341392993927,
-0.41701117157936096,
1.4429410696029663,
-0.0692063495516777,
0.7704790830612183,
-0.3188532590866089,
0.3850972056388855,
0.2854282855987549,
-0.5792303085327148,
0.8098104000091553,
-... | |
why do human beings like to collect things for the sake of collecting, and do any other species do it? | collecting, collect, evolutionary underpinning ====== i'm going to go out on a limb here, since most everyone has taken this to be about the evolutionary underpinning of collecting. i work in an art museum, and study the psychology of teaching/learning within them. the act of collecting is really loaded with social and... | 4 | [] | [] | [] | [
-0.09636527299880981,
1.2037817239761353,
-1.5264534950256348,
-1.8227967023849487,
-0.4604448676109314,
-1.7664591073989868,
4.394259929656982,
-3.552913188934326,
1.4140934944152832,
1.510571002960205,
0.3919854164123535,
-3.6884896755218506,
0.21282905340194702,
1.1594822406768799,
1.... | |
earth day and power system load | hi everyone, i'm starting to see earth day 2012 promo online and i'm wondering, when a whole lot of load is suddenly removed from the electrical system all at the same time, does it cause any significant damage to the electric generators? do power plants have to prepare for this event in advance? | loss of load, typically a loss, overspeed trips set ====== typically a loss of load does not cause damage to generators. generators specifically will have overspeed trips set related to a certain frequency (i.e. 66 hz in a 60 hz system) and various regions (at least in the us) have ways to deal with a sudden loss of lo... | 2 | [] | [] | [] | [
-0.8726782202720642,
-0.39288070797920227,
0.8531813621520996,
0.7142162322998047,
0.06082610785961151,
-0.19178566336631775,
-0.7864282131195068,
1.1662226915359497,
-0.32030805945396423,
-0.5782447457313538,
-0.5331811904907227,
1.705395221710205,
-0.5091513991355896,
-0.8585357666015625... |
the sambuca "gas chamber" shot, what is going on here? | _url_0_ you light a shot of sambuca in a snifter, you pour the flaming shot into another waiting glass while keeping the snifter held upside down above the flames (this catches the "alcohol fumes"). after the shot had extinguished, set the still upside down snifter on the bar or table, take the shot and then, by tippin... | combustion route products, sambuca it flavour, route products ====== not including the chemicals that give sambuca it's flavour, i'd imagine they're just inhaling co2 and h2o among other combustion route products. there's probably some unreacted ethanol in there as well but you're better off drinking the stuff. as a mu... | 2 | [] | [
"http://youtu.be/se42dyN2C8Q"
] | [
"http://www.ncbi.nlm.nih.gov/pubmed/2961648"
] | [
0.05902606248855591,
-0.09691187739372253,
0.16859400272369385,
0.5298459529876709,
0.23632195591926575,
-0.6664673089981079,
0.5940368175506592,
0.8353244066238403,
-0.3349010646343231,
-0.35276105999946594,
-0.3377118706703186,
0.26708701252937317,
-0.8080623745918274,
0.8827800750732422... |
how can the "runner's knee" be so poorly understood? | so, i was informing myself about patellofemoral syndrome and i was shocked when i learnt how little is known about it. i read from wikipedia that: > the causes of pfps are unclear, but there are several theories. which issues give rise to the pain is debated. similarly, there is no consensus as to what is the best way ... | research society conference, orthopedic research society, las vegas ====== greetings from the orthopedic research society conference in las vegas! there are thousands of orthopedic researchers and clinicians here for 5 full days of talks, posters, and presentations on current orthopedic research. there are about 60 or ... | 5 | [] | [] | [] | [
-0.13868474960327148,
-0.20410853624343872,
0.5454214811325073,
-0.17533910274505615,
-0.8698071837425232,
-1.4441832304000854,
-1.3721890449523926,
0.36764290928840637,
1.551639199256897,
-0.7769691944122314,
-0.2351686805486679,
1.9198497533798218,
-0.20261281728744507,
0.443392783403396... |
what causes the body's rejection response? | specifically in an organ transplant (kindey, liver, heart, etc). what are some of the factors decide if the body accepts or rejects the new addition? | protein complex called, complex called mhc, tour immune cells ====== immunology was a few months ago but from what i recall, the overall idea is that almost all of your cells express a protein complex called mhc, there are two types of mhc and they just have a space where they present little pieces of your proteins to ... | 2 | [] | [] | [] | [
-1.921708345413208,
0.30940547585487366,
-0.10942411422729492,
-1.5145634412765503,
-1.6214828491210938,
-1.1896167993545532,
1.0387492179870605,
1.166123390197754,
2.7458503246307373,
0.32093217968940735,
-0.2401617467403412,
-0.9085633754730225,
0.30871808528900146,
-0.010629002004861832... |
the more i read about hep c the more scared i get | i have been reading a lot about it since 2 people i know have now tested positive even though there is no way they have engaged in any obvious risk activities. now i am reading that 10-20% of people have no idea where they contracted it, it can be spread in microscopic drops of blood, through chapped skin. it can also ... | study you cited, virus, rna ====== as you mentioned, hepatitis c can survive for a while outside of the body, but one problem with the study you cited was that it did not look at active virus. what they did there was use rt-pcr to detect rna from the virus, and while rna is necessary for the virus to cause infection, r... | 12 | [] | [
"http://www.hepcprimer.com/xmit/haircut.html"
] | [
"http://www.epa.gov/oppad001/list_f_hepatitisC.pdf",
"http://www.cdc.gov/hepatitis/HCV/"
] | [
-1.773263692855835,
0.1951974332332611,
-1.8797972202301025,
-0.5583497881889343,
0.6105291843414307,
-0.02039983868598938,
0.21575838327407837,
1.3981906175613403,
-0.3971549868583679,
-1.2740581035614014,
1.0727342367172241,
0.7105341553688049,
-1.442294955253601,
0.8593361377716064,
-... |
is exercising regularly a "free pass" to eating unhealthy foods? | if i exercise regularly, am i lessening the amount of 'damage' or adverse effects of unhealthy foods that i eat? is it still unhealthy, but just not as unhealthy? perhaps an explanation of what is at work when i am exercising/eating is in order here. this question has been on my mind for sometime and i finally have a g... | eating only twinkies, prove a point, nutrition professor ====== relevant is the story of a nutrition professor who lost 27lbs in 10weeks eating only twinkies, chips, and cookies by reducing his overall caloric intake and exercising to prove a point. despite the poor nutritional value the lost weight increased his overa... | 13 | [] | [] | [
"http://www.cnn.com/2010/HEALTH/11/08/twinkie.diet.professor/index.html"
] | [
-0.6254899501800537,
1.1679556369781494,
0.1323925405740738,
0.09896516799926758,
0.00734846293926239,
-0.11295340210199356,
0.6121412515640259,
0.7596902847290039,
-0.24555081129074097,
-0.12019574642181396,
0.4817836284637451,
-0.25645187497138977,
-0.3831358253955841,
0.5984434485435486... |
i have a couple questions about obsidian. | 1) as far as i know, which granted, isn't very far, obsidian is formed when lava cools more quickly. if this is the case, why does it not form when lava hit water? 2) a lot of ancient peoples made tools out of obsidian, but they were all made by chipping. with our modem technology, can we carve obsidian? specifically i... | abrasive processes, formed using abrasive, obsidian ====== obsidian can be formed using abrasive processes (e.g. sanding). i don't know about going after it with a hammer and chisel, but i doubt it could be carved in that fashion due to its fracture behavior. i've seen plates and bowls, and some really lovely jewelry c... | 3 | [] | [] | [] | [
0.434019535779953,
1.3659273386001587,
0.8265771269798279,
-0.7795438766479492,
-2.0165088176727295,
-1.7977349758148193,
-0.9610979557037354,
-0.8775306940078735,
-0.15085123479366302,
0.13139212131500244,
-1.1168593168258667,
0.5271617770195007,
-0.16955147683620453,
-1.065786361694336,
... |
are there any turtle experts here? i often stop and move turtles out of the road. is it better to just move them to the side of the road or to take them someplace away from roads? | i usually just place them in the grass on the side they were moving toward, but occasionally i have taken them to a completely different location, such as a park with a pond or lake. which is better for the turtle? i was wondering if it makes any difference to the turtle to be taken miles away from where i found it. i ... | turtles, nesting movement, turtle expert ====== turtle expert here. turtles on the road are either trying to nest on the shoulder or are crossing the road. if it is a very aquatic species (alligator snapper, any of the softshells, musk turtles (*sternotherus*), map turtles (*graptemys*), it is almost certainly a nestin... | 3 | [] | [] | [] | [
1.5298025608062744,
-1.2250056266784668,
2.7133727073669434,
0.6147465705871582,
0.11414451152086258,
-3.098271369934082,
2.9389290809631348,
-3.2488763332366943,
0.5195497274398804,
0.3399108648300171,
2.127413272857666,
0.285078227519989,
0.7503156661987305,
0.2032703310251236,
1.11405... |
how bad is teflon really? | a friend of mine came over to visit for the holidays. he saw my pans and almost refused to eat out of them because they were a bit worn and had a teflon surface. they were expensive high-quality items a long time ago. he said "the grease has gotten into the pan ..." now i have heard that teflon is not that good for you... | absorbed grease, inert substance, grease ====== under most circumstances, teflon is an inert substance which therefore cannot harm you, and even if it is porous and has absorbed grease, that grease is also not harmful, it just adds to the lubrication of the pan. it is also true that if teflon is exposed to very high te... | 25 | [] | [] | [] | [
-3.2249295711517334,
-0.3449866473674774,
0.5033788681030273,
0.3836432099342346,
0.521767795085907,
-2.11083984375,
1.1431803703308105,
2.780529737472534,
-1.0755873918533325,
-0.04829607903957367,
-1.0386158227920532,
0.22153301537036896,
-0.5381044745445251,
0.8887309432029724,
-0.294... |
does a low plasma osmolality imply that we have a low blood volume, and vice versa? | and does that mean a high plasma osmolality implies high blood volume? | volume, high, blood ====== the short answer is no. the most commonly seen situation where a person has a high blood volume is heart failure. the simplified mechanism is that the heart is having trouble pumping and the body sees it as not having enough blood so it retains sodium. as water follows solutes, water is retai... | 4 | [] | [] | [] | [
-1.3534440994262695,
0.5621561408042908,
2.639688014984131,
2.8692855834960938,
-1.7634925842285156,
-2.823906660079956,
0.9048628211021423,
2.8418591022491455,
0.6115344762802124,
-0.8751261234283447,
1.5485612154006958,
-1.6358312368392944,
-1.5423005819320679,
0.765723466873169,
-0.95... |
pollutants from china in grand canyon? | in summer of 2008 my wife and myself were visiting the grand canyon. being from hawaii, and other than volcano haze, we are used to quite clear skies. we were astonished at how much haze was in, and around the grand canyon seriously cutting the view. we inquired a park ranger who told us most was from north america, bu... | regional haze, regional, particles ====== regional haze (which is the regulatory term for what you're describing) is obviously generated by pollutants, and specifically nitrates, sulfates, and particles. the epa even has a regulatory program designed to deal with regional haze and improve visibility, with specific visi... | 5 | [] | [] | [] | [
1.6986262798309326,
0.14221861958503723,
2.3595988750457764,
2.4455184936523438,
5.992011070251465,
-1.0556045770645142,
1.4863746166229248,
0.021396934986114502,
0.012743696570396423,
0.16086505353450775,
-0.2382841557264328,
-2.4919896125793457,
0.21446943283081055,
-0.39265239238739014,... |
do we need to do relativistic adjustments because of galactic motion? | during a recent conversation we found that the earth is moving at around 10% lightspeed towards the leo constellation due mostly due to the motion of the milky way. does this mean that we need to take this into account due to relativity when doing any kind of precise measurements? it's my understanding that because lig... | lights speed, speed, lights ====== 10% of lights speed? i'm pretty sure it's only a few hundred kilometers per second. anyway, the answer is that things in their own rest frame always feel at rest. time passes at one second per second. | 2 | [] | [] | [] | [
0.4770572781562805,
-0.36724668741226196,
0.25804415345191956,
0.630139172077179,
-0.2693048417568207,
-0.013714253902435303,
0.35630640387535095,
0.43919557332992554,
0.8412527441978455,
-0.6224392652511597,
-0.23535935580730438,
0.4940912127494812,
0.04942089691758156,
-0.228239268064498... |
a few gravity/time related questions. | i had a documentary on tv the other day regarding albert einstein. i wasn't paying too much attention but one thing did catch my attention. albert einstein had a theory that time is affected by gravity and that gravity actually slows time down. (whether this has been proven true or not or whether it is still a theory i... | effects of time, time dilation, question ====== regarding your third question, effects of time dilation are not felt. this is true for gravitational and doppler dilation. your clock ticks at a normal pace. someone on earth would appear to move quickly from your point of view. its all relative, hence the name. | 3 | [] | [] | [
"http://www.dailymail.co.uk/home/moslive/article-1269288/STEPHEN-HAWKING-How-build-time-machine.html**"
] | [
-0.26311373710632324,
-0.24215379357337952,
0.33222225308418274,
0.4770765006542206,
-0.026093095541000366,
-0.26721447706222534,
0.6233735680580139,
0.28393059968948364,
1.781854271888733,
-0.3919280767440796,
0.9897736310958862,
-0.1450117826461792,
-0.18668745458126068,
0.10369742661714... |
can two things truly be said to happen at the same time? | if two things seemed to happen at the same time you could watch it in slow motion and realize one started to happen sooner. could two things actually happen exactly at the same time? | absolute meaning, events happening simultaneously, events happening ====== there is no absolute meaning to events happening simultaneously. one of the lessons of relativity is that the notion of two things happening at the same time is observer-dependent. if some observer measures two events to occur simultaneously, th... | 8 | [] | [] | [] | [
0.4404910206794739,
-0.2828521430492401,
-0.15071061253547668,
1.0616140365600586,
1.3828524351119995,
0.6260864734649658,
0.7080247402191162,
-0.9748338460922241,
2.472811698913574,
-0.38849925994873047,
1.3541384935379028,
0.2754392921924591,
-0.16498132050037384,
-0.35040345788002014,
... |
what major stars can be seen in pennsylvania but not in florida? (and vice versa) | specifically the latitudes of 41°n and 28°n | ignoring the fact, things very close, centaurus alpha centauri ====== ignoring the fact that it's hard to see things very close to the horizon. you'd be looking for stars between [declination](_url_1_) -49 degrees and -62 degrees, which is the strip of sky that you can see in florida but not pennsylvania at the latitud... | 10 | [] | [] | [
"http://www.nexstarsite.com/Downloads.htm",
"http://en.wikipedia.org/wiki/Declination#Stars"
] | [
0.7594606876373291,
0.22797659039497375,
2.487273931503296,
1.023550271987915,
0.1585899293422699,
-1.6851584911346436,
-1.3626128435134888,
-1.2228773832321167,
0.5971381664276123,
-0.8947516083717346,
1.080077886581421,
0.6047588586807251,
-1.7079434394836426,
-1.369309425354004,
0.459... |
mystery liquid in my grandpa's basement | white paint, dense, white ====== could be just white paint? titanium dioxide is 4.3 times as dense as water. a paint with tio2 would be less dense than that, but probably not much less dense. | 3 | [] | [] | [] | [
-0.04265734925866127,
0.4804540276527405,
0.28212690353393555,
0.639015793800354,
0.43348586559295654,
-0.5052570104598999,
-0.2982671558856964,
0.5563008785247803,
-0.42968305945396423,
-0.43537652492523193,
-0.4642212986946106,
0.4091554284095764,
0.1528204083442688,
0.10011227428913116,... | |
what is information in the context of physics? | my question is: is information considered a physical property of the universe or of it's objects in a modern physics setting? if so, what is the definition of information, and how does it relate to other properties? context: i've seen information (measured in bits) come up in some physics discussions and articles in wi... | url, mathematically similar, shannon entropy ====== when "information" is measured in bits, they are using [shannon's entropy](_url_0_), which is mathematically similar to [gibbs entropy](_url_1_) differing by a constant (and the units). regardless when used in such a context information can be interpreted as the minim... | 9 | [] | [] | [
"https://en.wikipedia.org/wiki/Entropy_(information_theory\\)",
"https://en.wikipedia.org/wiki/Entropy_(statistical_thermodynamics\\)#Gibbs_entropy_formula",
"http://forums.xkcd.com/viewtopic.php?t=113079"
] | [
-1.353623390197754,
-0.7518616318702698,
0.21648067235946655,
-1.5274028778076172,
-0.8698040843009949,
-0.5998663902282715,
-0.5530143976211548,
0.7639446258544922,
1.096521258354187,
0.08283675462007523,
-1.01811945438385,
-0.40600574016571045,
1.7139095067977905,
1.3294258117675781,
0... |
a question about electricity | so a tv show got me thinking about resistance and the conversion from electrical energy to thermal energy. the details of the show don't matter but the question i ended up with is, given constant voltage, would more heat be generated in a insulator or in a conductor? would it be the same? in a insulator the current is ... | lower resistance produces, lower resistance, converted using ohm ====== the heat output of a resistor is i^2 \*r, where r is resistance and i is electrical current. that can be converted using ohm's law v=i\*r to v^2 /r. so with the same voltage, lower resistance produces more heat output which is actually because more... | 5 | [] | [] | [] | [
-1.8781145811080933,
1.841806173324585,
0.016050800681114197,
1.112083911895752,
-1.0471482276916504,
-0.22290879487991333,
0.7246093153953552,
0.8523509502410889,
0.3919970393180847,
-0.15721853077411652,
0.2321585714817047,
-0.3618212342262268,
0.035463493317365646,
-0.3327837288379669,
... |
are there any methods of recording uncertainties without observing them? | quantum mechanics has many particles and functions which are in a state of uncertainty until they are observed, where they collapse into a single state. my question is, are there any methods, theoretical or real, to record such things for future observation? for example, is it possible to freeze a quantum state in time... | quantum, superposition, uncertainty ====== there's a lot of questions in this post and some things you seem confused on, so i'll try to address each thing one by one. let's start with the confusion. you're confusing *uncertainty* with *superposition*. an "observable" (a property that you can measure, like position, mom... | 8 | [] | [] | [
"http://www.physicsclassroom.com/Class/waves/swf.gif",
"https://en.wikipedia.org/wiki/Many-worlds_interpretation",
"https://en.wikipedia.org/wiki/Ghirardi%E2%80%93Rimini%E2%80%93Weber_theory",
"https://en.wikipedia.org/wiki/Copenhagen_interpretation"
] | [
-4.232426166534424,
-2.2347335815429688,
-0.6933070421218872,
0.689873456954956,
-1.4818720817565918,
-1.974373459815979,
2.0958683490753174,
-1.2745616436004639,
5.195135116577148,
-0.6538241505622864,
4.228985786437988,
-1.3681530952453613,
0.2743016481399536,
0.07017958164215088,
2.06... |
is there an activity like "herping" but with small mammals? | herp derp, thing on reddit, stupid ====== by the way, please no downvotes because of the stupid "herp derp" thing on reddit. this is a real thing; here's proof: _url_0_ | 5 | [] | [] | [
"http://en.wikipedia.org/wiki/Herping"
] | [
-0.3950079679489136,
-0.22818389534950256,
-0.20690754055976868,
-0.24442841112613678,
-0.18080756068229675,
0.07348433881998062,
0.13491679728031158,
0.13820286095142365,
0.1367109715938568,
-0.18845543265342712,
-0.05220956727862358,
-0.10709690302610397,
0.31425902247428894,
-0.20640505... | |
questions about fluid mechanics in atomic/molecular level. | i'm generally interested on how well we can derive macroscopic behavior of fluids if we know the structure of particles that make up the fluid and how much the shape and structure of particles affects the fluid equations. i'm completely ignorant of the subject (i know about reynolds number but that's it). i can't even ... | water, molecule, water molecules ====== it's a fair question: we can't derive them very well, actually. with fluids, you traditionally model it at the macroscopic end, where it's assumed to be homogeneous if not more (say, incompressible and whatnot). you use parameters describing bulk properties such as density, dynam... | 2 | [] | [] | [
"http://en.wikipedia.org/wiki/Rigid_rotor",
"http://en.wikipedia.org/wiki/File:Proton_Zundel.gif",
"http://en.wikipedia.org/wiki/Intermolecular_force",
"http://en.wikipedia.org/wiki/Navier%E2%80%93Stokes_equations",
"http://en.wikipedia.org/wiki/Fluid_mechanics"
] | [
-9.305604934692383,
1.1266872882843018,
-1.452723503112793,
3.1253278255462646,
1.533134937286377,
-5.178260326385498,
4.1928629875183105,
7.7522993087768555,
5.625021457672119,
-3.1806938648223877,
5.558147430419922,
-3.7070040702819824,
-4.505533695220947,
7.289959907531738,
8.45352458... |
how does qpcr work for quantification? | i understand the idea of pcr is to amplify dna but how does qpcr enable us to quantify dna (through sybr green or taqman)? what exactly does it allow us to quanitfy? and why would we want to quantify what it allows us to quantify? | mouse, dna, sample ====== okay here we go: when you do pcr, you're getting exponential amplification of dna, because you have 1 copy - qpcr works the same way. the dye in the loose nucleotides fluoresces only when incorporated into double-stranded dna, so when you go through a cycle and your dna doubles, it will glow t... | 4 | [] | [] | [] | [
-1.2862986326217651,
-4.329549312591553,
-0.47454825043678284,
-1.3895976543426514,
-2.027148485183716,
-3.9868903160095215,
-4.839638710021973,
4.041093349456787,
4.383854866027832,
-4.0492262840271,
4.337775707244873,
0.12228181958198547,
-4.83938455581665,
1.8373159170150757,
-6.68412... |
what caused the 750 gev diphoton excess at cern? | i'm interested in what specific mechanism would have caused the exact same statistical anomaly to effect both atlas and cms? what exactly causes anomalies like this to appear? | random chance, random, chance ====== statistics. specifically, random chance. the actual measurement in this case was "how many pairs of photons did i find with this particular energy." the physical processes that produce these photons are fundamentally random due to quantum mechanics, so while we can predict how many ... | 9 | [] | [] | [] | [
-1.3680518865585327,
0.028432756662368774,
2.032979965209961,
0.6681675910949707,
1.340240240097046,
-2.772582769393921,
1.675357460975647,
0.9539252519607544,
4.655945301055908,
-2.7266151905059814,
1.1757677793502808,
0.14684945344924927,
2.2049148082733154,
-2.415138006210327,
0.34299... |
i just planted seeds. what are they doing now? | specifically, in the first few hours in a good environment with water? | seeds, great deal, water ====== the answer to this is "not a great deal in the first couple of hours" though it very, very much depends on what seeds they were. the principal triggers for germination are sufficient water availability, oxygen and the correct termparture range. with those 3 things right seeds will germin... | 13 | [] | [] | [] | [
-4.021624565124512,
2.029158353805542,
1.395546793937683,
3.050551414489746,
4.6943559646606445,
-0.7842464447021484,
0.2751017212867737,
0.6040210723876953,
-0.4117080271244049,
1.9584176540374756,
1.3069531917572021,
1.0727474689483643,
-5.077605247497559,
2.0001208782196045,
-0.482495... |
math-metrology-history question. why did industry pick 1/64ths? | i know most of the world uses the metric system. i'm also aware they make 1/100" marked machinist rules and "engineering tape measures" which are marked in tenths of a foot. everybody loves base 10, i get it. if i want extreme accuracy i'll use a micrometer, not a machinist's rule. this is purely a historical interest ... | easier to divide, eyeball measure., sight ====== it's easier to divide by two when it's an eyeball measure. and 1/64" is about as low as you go by sight. | 7 | [] | [] | [] | [
0.4058230221271515,
0.19222788512706757,
-0.23933172225952148,
-0.017247473821043968,
-0.08196563273668289,
0.253436416387558,
0.08552411198616028,
-0.049170754849910736,
-0.014974218793213367,
-0.21428531408309937,
0.10228008031845093,
-0.08467929810285568,
-0.156643807888031,
0.313179522... |
do we live in a cause-and-effect universe? are there things that happen for no apparent reason? | is there a 'root cause' to things? if you look at what causes something, and what causes that cause, and so on, will you eventually get to something that couldn't possibly have a cause (barring metaphysical speculation)? sorry if the questions are vague or if they don't make sense, just point it out if that's the case.... | heard a ping., ping-shaped pressure wave, pressure wave reached ====== you just heard a ping. why? because a ping-shaped pressure wave reached your ear. why? because a bell rang. why? because an electrical circuit closed. why? because your detector detected an electron. why? because a nearby free neutron decayed. why? ... | 62 | [] | [] | [] | [
-0.4694886803627014,
0.41589224338531494,
0.6048750281333923,
-0.2735084295272827,
-0.30423957109451294,
-1.4068217277526855,
0.09164780378341675,
0.770418107509613,
0.04185664653778076,
-0.8863750696182251,
0.5596193671226501,
-0.1330762505531311,
-0.1301598697900772,
-0.21670761704444885... |
what applications does very high current (1ka+) have? | i noticed a terminal box (or whatever those cabinets full of electricity are called) with a warning label stating a current of about 1.3ka and haven't been able to work out what it would be for. cheers! | devices drawing current, multiple devices drawing, devices drawing ====== if you have multiple devices drawing current at the same time, you have to be able to deliver the sum total of all their currents. if you have a single window air conditioner in your apartment, that's ~5a of current. if you have an apartment buil... | 7 | [] | [] | [
"https://en.wikipedia.org/wiki/Z_Pulsed_Power_Facility"
] | [
-0.17937147617340088,
0.22676251828670502,
0.47122472524642944,
0.3074376583099365,
-0.8103104829788208,
-0.6478601098060608,
-0.5175453424453735,
-0.6768930554389954,
0.27490413188934326,
-0.0001685693860054016,
-0.2409621626138687,
0.792388379573822,
0.22290220856666565,
-0.0353298261761... |
comment algorithms (xpost askcomputersci) | i have been reading about reddit's 'best' comment sorting algorithm here (_url_0_) and got to thinking; how do sites that don't have a downvote sort comments? or rather, how should they? are there any well-known scoring algorithms that work only using the up-vote? to take the lower-bound of the wilson score interval (_... | crosspost my response, interesting topic, sentiment analysis includes ====== i'll crosspost my response here, as i think it's an interesting topic that people from beyond cs could weigh in on. --- opinion mining and sentiment analysis includes research into ways to assess the information content, interestingness or rel... | 2 | [] | [
"http://blog.reddit.com/2009/10/reddits-new-comment-sorting-system.html",
"http://en.wikipedia.org/wiki/Binomial_proportion_confidence_interval#Wilson_score_interval"
] | [] | [
-2.2582952976226807,
0.32796338200569153,
-0.569034218788147,
-1.2356990575790405,
0.8036035299301147,
0.022158734500408173,
-0.3517518639564514,
-0.3928447663784027,
-0.429962694644928,
-0.17871886491775513,
0.21339017152786255,
0.19776910543441772,
0.1506328582763672,
-0.416975200176239,... |
i was reading about gout in a textbook, and i learned that it is prevalent in humans and larger primates because of an evolutionary loss of the enzyme uricase, which would break down excess uric acid. how exactly is something like this lost by evolution? | title pretty much sums it up. i'm not interested in uricase specifically, more about how a gene would be inactivated/modified/removed because the organism may be better without it i normally consider myself pretty good with genetics and evolution, but i've never really learned this side of it. | gene, uricase gene, time by evolution ====== it's quite easy for a gene to be lost over time by evolution. mutations that knock out a gene function or expression will persist in a population if those mutants can thrive and compete. i imagine that one of the common ancestors of both humans and apes lost its uricase gene... | 2 | [] | [] | [
"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC349151/"
] | [
-1.547556757926941,
-1.0195717811584473,
-0.7541003227233887,
-0.4064258933067322,
-1.0404112339019775,
0.010139942169189453,
-0.855610728263855,
0.6076451539993286,
1.3495169878005981,
-0.27961286902427673,
2.105224609375,
-0.2594003677368164,
-0.8194219470024109,
0.38810884952545166,
0... |
how are hazard ratios interpreted? | i am curious about the interpretation of hazard ratios, particularly from this study: _url_0_. i thought it used to be open access, but if it was, it isn't now. their conclusion was that a high intensity of exposure to formaldehyde leads to a much higher risk of als death. it's somewhat confusing because they never add... | nice explanation, level of formaldehyde, confidence interval ====== i don't know too much about this, but this seems like a nice explanation: _url_0_ essentially, a hazard ratio is the probability of an event (in this example, als mortality) in some experimental group (respondents exposed to some level of formaldehyde)... | 3 | [] | [
"http://jnnp.bmj.com/content/early/2015/06/24/jnnp-2015-310750"
] | [
"www.medicine.ox.ac.uk/.../what_are_haz_ratios.pdf",
"http://www.students4bestevidence.net/a-beginners-guide-to-interpreting-odds-ratios-confidence-intervals-and-p-values-the-nuts-and-bolts-20-minute-tutorial/"
] | [
0.7117786407470703,
0.14934271574020386,
0.011080145835876465,
0.9484866261482239,
1.4476220607757568,
1.5023773908615112,
0.05769139528274536,
0.6360660195350647,
2.4822099208831787,
-0.8826179504394531,
3.21728515625,
0.4339827001094818,
1.6644498109817505,
-1.077932357788086,
0.061004... |
crumple zones | can someone explain the physics behind crumple zones in cars using formulas backing them up? | crumple zones spread, zones spread, time ====== crumple zones spread out momentum transfer over a longer time. the change in momentum imparted on an object during a collision is usually referred to as impulse. in simple terms, impulse is the force applied times the time period in which a force acts. deltap = i = f x de... | 3 | [] | [] | [] | [
-2.086604595184326,
-0.3586311936378479,
-1.1069308519363403,
-0.8511812090873718,
-0.5695849657058716,
-0.999740481376648,
1.288507342338562,
1.2435598373413086,
2.8908286094665527,
-0.24457275867462158,
1.4988975524902344,
1.5010648965835571,
0.6719568967819214,
-0.747776985168457,
0.9... |
i recently read about a lamp that uses salt water and magnesium & carbon rods to create electricity for its power source. what exactly is going on here? | here is an excerpt from the [press release](_url_0_): > **led lantern powered only by water, salt** > the lantern, "gh-led10wbw," does not require a dry cell or rechargeable battery and emits light when water and salt are put in the lantern. it can continuously generate electricity for eight hours per charge of water. ... | wet cell, called a wet, add an electrolyte ====== this thing **is** a battery (this type of battery is called a wet cell), the only difference is that you add an electrolyte instead of having it come in the battery. this particular type of battery wouldn't be very good for high power applications (lithium batteries wou... | 5 | [] | [
"http://techon.nikkeibp.co.jp/english/NEWS_EN/20120904/237751/"
] | [] | [
-1.4579126834869385,
0.4744623899459839,
0.18208524584770203,
0.45634692907333374,
0.3357951045036316,
-0.8330163955688477,
1.2042889595031738,
1.1943551301956177,
-0.6221592426300049,
-0.06835269182920456,
0.3686818480491638,
0.09625428169965744,
0.44013047218322754,
0.8652656078338623,
... |
could someone explain to me the meaning of this physics equation? including its variables? | here is a picture of the [equation] (_url_0_). and [here](_url_1_) is the link to to the blog where i found this equation. | integral, bit snarky, meant ====== the blog is being a bit snarky, but it is a condensation of all known physics theory into one equation. the point is that physics is pretty simple. there are "only" ~~four~~three forces to deal with: gravity, electromagnetoweak forces, and strong forces, and it's possible with our pow... | 8 | [] | [
"http://www.preposterousuniverse.com/blog/wp-content/uploads/2013/01/Everyday-Equation-1024x353.jpg",
"http://www.preposterousuniverse.com/blog/2013/01/04/the-world-of-everyday-experience-in-one-equation/"
] | [] | [
-4.210134983062744,
-0.0715072974562645,
-0.4898488223552704,
-1.5611823797225952,
-2.526325225830078,
-1.9055825471878052,
5.138750076293945,
-0.4227488040924072,
5.905053615570068,
-1.5592710971832275,
2.6939892768859863,
-0.4716087877750397,
0.9268267750740051,
2.0979862213134766,
1.6... |
what human beings have traveled the farthest? | cumulatively in their lifetime relative to the earth. i suspect it is either astronauts who have spent time on the iss, or airline pilots. | average, average speed, total distance traveled ====== average speed during that time ~28,000 km/h. total distance traveled ~540,000,000 km. ----- average speed of commercial jet ~800km/h. to match distance of 540million km ~675,000h=75 years. ----- so it would be the orbit guy. unless there has been a person who has b... | 11 | [] | [] | [] | [
2.0999677181243896,
1.1676563024520874,
-0.1242334246635437,
-0.8316161632537842,
-1.2730268239974976,
-1.5726873874664307,
0.8757936358451843,
1.6087919473648071,
-0.003052651882171631,
-0.7814948558807373,
1.5120810270309448,
0.654751181602478,
-0.5231785774230957,
-0.029247954487800598,... |
how did the oxygen evolving complex of psii come to be in its present form? | i am referring specifically to [this](_url_0_) ligand as described in the pdb. were there stages in the structure that we know of before this, admittedly, complex structure as we know today became what it is? | uniform electron density, electron density caused, x-ray crystallography ====== we don't fully know what the structure is _right now_, x-ray crystallography has bad resolution of the site because of the high and relatively uniform electron density caused by having so many metal atoms in close proximity. (note for insta... | 19 | [] | [
"http://www.rcsb.org/pdb/ligand/ligandsummary.do?hetId=OEX&sid=3ARC"
] | [
"http://en.wikipedia.org/wiki/File:Manganese_cluster.svg",
"http://en.wikipedia.org/wiki/Iron-sulfur_protein",
"http://i.imgur.com/Xcc27bu.png"
] | [
-1.821341872215271,
0.7003462314605713,
-0.253245085477829,
1.1255170106887817,
-0.17432966828346252,
-1.4831082820892334,
-2.175506591796875,
0.4465033710002899,
0.946474015712738,
-0.8304197788238525,
1.1683884859085083,
0.11108899116516113,
-0.4919531047344208,
-0.01228553056716919,
0... |
whats the most efficient way to use two different insulation materials with different r-values. should the material with the higher r-value be used closer to the heat source? | when winter camping many people like to stack two sleeping pads on top of each other. normally, these pads have different r-values, one is usually inflatable with a high r-value, the other is made from closed cell foam and has a lower r-value. almost everyone agrees, the ccf sleeping pad should go below the inflatable.... | ordering of pure, dew point, vapor ====== technically, there is no difference in the ordering of pure r materials. the r's add up. the air mattress will support internal convection which changes its behavior over temperature, but i'm pretty sure you can just dial that in to the effective r factor for camping purposes. ... | 44 | [] | [] | [] | [
-1.3287614583969116,
0.603036642074585,
1.2898073196411133,
1.1797189712524414,
2.5099663734436035,
-0.28030693531036377,
2.8704307079315186,
0.47465813159942627,
-0.09855203330516815,
0.4295724034309387,
1.2732471227645874,
-1.8725215196609497,
-0.38463789224624634,
0.6592135429382324,
... |
is it just an amazing coincidence that there are exactly two equinoxes per year? | or is there some rotational/tidal resonances occurring? | fact that earth, earth axis, axis of rotation ====== no, it's due to the fact that earth's axis of rotation is at an angle with respect to its angle of orbit. | 3 | [] | [] | [] | [
-0.04948841780424118,
-0.17221419513225555,
-0.38426393270492554,
-0.35734954476356506,
-0.03246283903717995,
-0.19781140983104706,
0.016261210665106773,
-0.060961440205574036,
0.7948612570762634,
-0.05531296879053116,
0.33885785937309265,
0.1268487572669983,
0.046751055866479874,
-0.04034... |
what is real world example of a fourth order control system? | in my mechatronics class, we're going over some basic control systems and we were given examples of first, second, and third order control systems. we were told that a cruise control is a good first order example, a spring-mass damper is a good second, and a pid controller is an example of a third order control system.... | quick google search, google search found, vibration control ====== i didn't know off-hand of any applications but a quick google search found that it is frequently of concern in robotics and mechatronics with respect to motion and vibration control. conceptually, if you have mass-spring-damper (or even just mass-spring... | 2 | [] | [] | [] | [
-1.4898909330368042,
-0.5767112970352173,
0.24238575994968414,
0.47887468338012695,
-0.03911755979061127,
-0.9146654009819031,
-0.1214287281036377,
-0.22482971847057343,
0.6437734365463257,
-0.34362179040908813,
0.15172381699085236,
1.2820433378219604,
-0.09751467406749725,
0.0368870645761... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.