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Friday, May 19, 2017

If each day is only 23h56m4s, over the course of 4 years, we accumulate 95.7 hours of unaccounted time when approximating each day to 24 hours. We give ourselves one extra day in February, which accounts for only 24 hours of that extra time, but where does that extra 71.7 hours go?

If each day is only 23h56m4s, over the course of 4 years, we accumulate 95.7 hours of unaccounted time when approximating each day to 24 hours. We give ourselves one extra day in February, which accounts for only 24 hours of that extra time, but where does that extra 71.7 hours go?


If each day is only 23h56m4s, over the course of 4 years, we accumulate 95.7 hours of unaccounted time when approximating each day to 24 hours. We give ourselves one extra day in February, which accounts for only 24 hours of that extra time, but where does that extra 71.7 hours go?

Posted: 19 May 2017 07:01 AM PDT

This also means that our calendar should shift over 3 days every 4 years, changing the "location" of the seasons in our man made calendar

submitted by /u/fornoggg
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Why are the physical electromagnetic fields only the real part of E and B?

Posted: 19 May 2017 02:16 AM PDT

This says that the physical fields are only the real part of E and B, but this is not obvious to me.

Since

eix = cos(x) + i sin(x)

We get an imaginary part of the fields in the picture, but somehow these aren't actually a part of the fields, or how should i interpret i?

submitted by /u/Physix_R_Cool
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Is the earth still cooling from its formation? If so, does that mean eventually all tectonic activity will cease and our liquid mantle will solidify?

Posted: 18 May 2017 08:01 AM PDT

What's the max signal frequency on a DSL wire?

Posted: 19 May 2017 03:44 AM PDT

Edit: OK, I'll try to rephrase, because the DSL apparently has complex techniques for multiplexing & reducing echo & transmission errors..

Let's assume the simplest case, an analogue signal carrying a digital signal in a wire. What's the minimum frequency of the analogue signal that can carry a bandwidth of x Kbps?


Original question: So the telco is saying that my copper wire can provide up to about 35Mbps of DSL connection speed. Does this mean that the carrier signal in the wire is at 35MHz, a little higher, or double of that? Why?

submitted by /u/KRBT
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What is the cause of diffusion and osmosis? How does it work?

Posted: 19 May 2017 05:13 AM PDT

I know the general gist of how diffusion/osmosis works, I just don't know why it works like it works.

submitted by /u/PersonalComputerG
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How do dogs make ATP?

Posted: 19 May 2017 07:10 AM PDT

Every being needs energy. Animals cells make ATP from sugar and oxygen. So where do dogs (and other meat eaters) get sugar from if they eat exceedingly meat.

submitted by /u/LeonardoM011
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Why is silver chloride so insoluble?

Posted: 19 May 2017 04:02 AM PDT

My guess is that the sizes of the silver and chloride ions are just right so the crystal is very stable and thermodynamically favoured over free ions?

submitted by /u/nicktohzyu
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What causes you to remember dreams?

Posted: 18 May 2017 07:20 PM PDT

Having a conversation with the boyfriend just before, we both dont remember alot of our dreams, However almost every night this week both of us have have had weird dreams that we remember the next day, Very unusual for us. Is it something we have eaten? Lack of sleep? Too much sleep? Chemicals in the body that are being produced? Please shed some light on this, this is weird and unusual, im spending half of my day trying to wrap my head around weird ass dreams!

submitted by /u/zoeysheree1993
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Since everything with mass has a gravitational pull, does this mean that Pluto has a pull on me currently?

Posted: 18 May 2017 07:12 PM PDT

To be more specific, I know everything that has mass has a gravitational pull, even atoms. I wanted to know, regardless of how small, if extremely far away planets/stars have an effect on us? It got me thinking that if time is infinite, will everything with mass, every atom, and every quark eventually come together as one big mass in space?

submitted by /u/smallwhales
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How much man-made space debris is there?

Posted: 18 May 2017 03:44 PM PDT

Pictures I see on the internet show space debris covering most of the surface. Obviously, the actual debris isn't that large or we'd be seeing it in the sky everyday. So, how much is actually there? What happens to it? How do we avoid the debris hitting spacecraft?

submitted by /u/Impatient_Nerd
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If electrons are so much smaller than than protons and neutrons, why can't we easily see atom nuclei with an electron microscope?

Posted: 19 May 2017 04:48 AM PDT

What happens with perspective in relation to a reflection in a mirror?

Posted: 19 May 2017 04:29 AM PDT

What I mean by this is the vantage point at the mirror or where you are standing? For example, when you are standing in front of a large hill and there are mountains in the background you can still see the mountains if you are far enough away from the hill, but if you get too close to the hill the mountain will disappear. If you stand just outside range of seeing the mountain and put a mirror (hypothetically tall enough) where you should be able to see the mountain if you were standing, would you see the mountain top or not? [http://imgur.com/a/sqFeR](Pictures of the scenarios I am trying to explain)

submitted by /u/Ilovechinesefood69
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At what point are planets considered to have "cleared the neighbourhood"?

Posted: 19 May 2017 03:22 AM PDT

The Jupiter is a planet, but it still gets hit by comets, which have regular orbits of their own. Saturn's ring is unstable enough that there may even be a new satellite forming out of the mass. Very slowly, but the Moon's orbit is slowly changing and away from the Earth. And then there are the occasional asteroid impacts. So what makes the term "clearing the neighbourhood" important in deciding if a body is a planet?

submitted by /u/seasaltandpepper
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If black dwarfs did exist, wouldn't they blend in with the cosmic background radiation, cooling off to this temperature?

Posted: 18 May 2017 09:16 PM PDT

Is there interpretation of quantum mechanics that violates principle of realism?

Posted: 18 May 2017 02:58 PM PDT

Quantum mechanics violates principle of local realism[1]. So far, we cannot really say whether QM violates only locality or realism or both. My understanding is, that it depends on interpretation of QM - e.g. Bohmian mechanics is nonlocal but doesn't violate principle of realism (if I am mistaken here, please correct me). My question therefore is whether there exists any specific interpretation of QM where we can say that it violates principle of realism (not necessarily only principle of realism)?

Also, it seems to me that various authors treat principle of locality and principle of realism differently, meaning that they are using different definitions of these two concepts. I believe that Bell defined what he meant by principle of locality in [2] - I believe he meant principle of locality in the sense of local causality (though I am not absolutely certain by it, so if anybody can correct me in this I would appreciate it). I also believe that principle of realism are basically hidden variables, am I correct?

[1] - pdf link to Bell's paper: "On the Einstein-Podolsky-Rosen Paradox"

[2] - pdf link to Bell's paper: "The Theory of Local Beables"

submitted by /u/Enfili
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Is the photon really massless?

Posted: 18 May 2017 02:35 PM PDT

When photons enter a medium they couple to phonons and acquire an effective mass. In vaccum however they move at c and are massless. But according to QFT the vacuum is also somewhat like a medium, so can photons in a vacuum really be considered massless or should we think of them having an effective mass as well? I know that there are fundamental principles behind the concept of a maximum speed of information exchange and that electromagnetic waves in a vacuum travel at that speed, but is that actually the end of the story?

submitted by /u/reedmore
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If the only thing keeping an electron in the lowest orbital from crashing into the nucleus is the quantization of energy, how can electron capture occur? Does the electron just go through a series of quantum jumps to the nucleus?

Posted: 18 May 2017 11:21 AM PDT

Is it possible for an element with zero protons and zero electrons to exist/have existed?

Posted: 19 May 2017 12:44 AM PDT

Similar to the element zero on the Mass Effect games. Is it possible for an element like that to exist and if so, how would it interact with other atoms and molecules?

submitted by /u/Davideroni
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Can an isotope have a negative number of neutrons?

Posted: 18 May 2017 08:40 PM PDT

proton = upQuark + upQuark + downQuark

neutron = downQuark + downQuark + upQuark

A nucleus can be described by its number of upQuarks and downQuarks, if their positions are a blur. On the other hand, many videos show protons and neutrons as nonoverlapping balls, which I take to mean vibrations that attract and repel at various distances. Can a neutron and proton in the same nucleus swap positions?

submitted by /u/BenRayfield
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Does pilot wave theory work with experimental results of (delayed choice) quantum erasers?

Posted: 18 May 2017 02:17 PM PDT

I've recently stumbled upon the 'dead but not dead' theory of pilot wave theory in QM. Allthough I did hear that apparently relativity doesn't work well with this theory, I wondered if the theory is consistent with measurement results of (delayed choice) quantum erasers. (I put delayed choice between parentheses because that specific experiment might be considered separately). I'm not too deep into QM, I followed courses on nanoelectronics and I have some experience with Schrodinger equations but in general, my math in QM is not up to speed. I'd like to hear the answer with the least amount of concessions as possible. So if complicated math is needed, feel free to. I'll just dive into it and see what I can learn.

submitted by /u/TunnelFET
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How do animals that camouflage really well find mates?

Posted: 18 May 2017 03:10 PM PDT

The same defense mechanisms which hide them from their predator/prey could also work against them and hide them from potential mates. This could also be very bad for the genetic pool if these animals can only breed with the immediate group they hang out with, right?

submitted by /u/_rb
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How does "polishing out" scratches work on a molecular level?

Posted: 18 May 2017 12:33 PM PDT

Hey today I read an article that said that you can try to polish out small scratches in gold. As gold is quite soft that makes at least some sense however I wondered how that works on a molecular level (u can be precise I am a physicist myself). It also stated that it is somewhat even possible with glas, does anyone know if that is true?

Cheers

submitted by /u/lschozar
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Thursday, May 18, 2017

They say that to test String Theory, we need to build a particle accelerator as large as out galaxy. Is it a technical limitation or a fundamental one?

They say that to test String Theory, we need to build a particle accelerator as large as out galaxy. Is it a technical limitation or a fundamental one?


They say that to test String Theory, we need to build a particle accelerator as large as out galaxy. Is it a technical limitation or a fundamental one?

Posted: 17 May 2017 10:09 AM PDT

Why do I feel like I need to cough when I stick a q-tip in my ear?

Posted: 17 May 2017 01:32 PM PDT

I know you're not supposed to do it, but I still do. When I stick a Q-tip in my ear, I get this overwhelming urge to cough. Why is that?

submitted by /u/Rottendog
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Why do we have to kill a horse when it broke its leg? What is the difference in biological processes between man and horse in bone mending?

Posted: 18 May 2017 03:12 AM PDT

How dangerous is uranium/uranium oxide to handle?

Posted: 17 May 2017 08:40 AM PDT

At 38:55 of the below video, it is said that people wear gloves when handling uranium to protect the uranium from being contaminated, rather than wearing gloves to protect themselves from the uranium. It is said that since uranium's half-life is in the billions of years, it isn't that radioactive.

This sounds hard for me to believe, as I thought uranium was very dangerous to handle. Is it true that uranium isn't that radioactive? That gloves are worn to protect the uranium, and not the human?

Also, is uranium oxide - which is what the pellets in the video are - the same as uranium in terms of safety?

https://youtu.be/H6mhw-CNxaE

submitted by /u/Fyreborn
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Light beam propulsion without lasers?

Posted: 18 May 2017 05:57 AM PDT

We now have the capability to do laser launch. The problem is the initial cost outlay for the lasers is still prohibitive to launch a sizable payload.

The estimate of the payload you can launch to Earth orbit dependent on laser power is about 1 kg per megawatt. So to launch thousand kilo payloads would require a gigawatt laser power levels. At current prices this would cost billions of dollars.

But is it possible to do it without using lasers, just using high intensity noncoherent light focused by mirrors or lenses?

I wondered about this because of two reports I saw doing a web search actually on optical communication:

InfiniLED MicroLEDs achieve 300 W/cm2 output density from tiny source. The MicroLEDs semiconductor manufacturing process includes construction of a parabolic reflector to enable optimal light control and high efficiency from micro-meter-sized LEDs. Published on:Jan 29, 2013 By Maury Wright

http://www.ledsmagazine.com/articles/2013/01/infiniled-microleds-achieve-300-w-cm-sup-2-sup-output-density-from-tiny-source.html

and:

Optical communications using coherent and non-coherent light.

http://modulatedlight.org/optical_comms/optical_about.html

The first report discusses micro-scale LED's whose light output scales up to 300 W per square centimeter, 3 megawatts per meter. From the appearance of these micro-scale LED's, they should permit simple automated production to produce many copies to cover a macro-scale area to generate light even at gigawatt power levels.

The second report discusses experimentation that suggests atmospheric dispersion is actually worse for lasers than for noncoherent light generated by LED's. See for instance the video in Fig. 2 on this page.

The advantage of the lasers however is that generating a parallel beam, you can use a parabolic mirror to focus the light at the focal point (more precisely at the Airy disk). Still, nevertheless a parabolic mirror will still focus a large portion of the light at the focal point even for noncoherent light.

So the question is if the beam is noncoherent, how much of the light can still be focused at the focal point (Airy disk)?

submitted by /u/RGregoryClark
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Why does boiling water make so much sound?

Posted: 18 May 2017 03:52 AM PDT

Ask Anything Wednesday - Biology, Chemistry, Neuroscience, Medicine, Psychology

Posted: 17 May 2017 08:04 AM PDT

Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Biology, Chemistry, Neuroscience, Medicine, Psychology

Do you have a question within these topics you weren't sure was worth submitting? Is something a bit too speculative for a typical /r/AskScience post? No question is too big or small for AAW. In this thread you can ask any science-related question! Things like: "What would happen if...", "How will the future...", "If all the rules for 'X' were different...", "Why does my...".

Asking Questions:

Please post your question as a top-level response to this, and our team of panellists will be here to answer and discuss your questions.

The other topic areas will appear in future Ask Anything Wednesdays, so if you have other questions not covered by this weeks theme please either hold on to it until those topics come around, or go and post over in our sister subreddit /r/AskScienceDiscussion , where every day is Ask Anything Wednesday! Off-theme questions in this post will be removed to try and keep the thread a manageable size for both our readers and panellists.

Answering Questions:

Please only answer a posted question if you are an expert in the field. The full guidelines for posting responses in AskScience can be found here. In short, this is a moderated subreddit, and responses which do not meet our quality guidelines will be removed. Remember, peer reviewed sources are always appreciated, and anecdotes are absolutely not appropriate. In general if your answer begins with 'I think', or 'I've heard', then it's not suitable for /r/AskScience.

If you would like to become a member of the AskScience panel, please refer to the information provided here.

Past AskAnythingWednesday posts can be found here.

Ask away!

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Where do prions originate from?

Posted: 17 May 2017 08:53 PM PDT

Can air "hold" alcohol (ethanol) like it can water at room temperature?

Posted: 17 May 2017 08:30 PM PDT

Hey guys. I know this question highly depends on the temperate and probably air pressure or something, so lets say typical summer day, 25°C (=77°F or 298,15°K), normal pressure. I place a bowl of pure alcohol in a room. Will alcohol "go" into the air like water would?

(Sorry for the words in "", I'm from germany and english isn't my native language so i was missing a few vocabularies :> )

submitted by /u/Truckermouse
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Can we only detect planets in systems that we see edge on?

Posted: 17 May 2017 05:13 PM PDT

I've heard that we use the transit method for identifying planets passing in front of stars. Does this mean that we can only detect planets if their orbital plane is along our line of sight?

submitted by /u/nyxo1
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If you stacked a lot of microscopic organisms, would you eventually be able to see them? What would they look like?

Posted: 17 May 2017 07:28 PM PDT

Assuming they don't move or run away, what would happen if you stacked (or piled up) a lot of microscopic organismic or just microscopic "things" in general. Disregarding the improbability/impossibility of finding that many of the organism, would you eventually pile up enough to be able to see them? Would it look like a solid mass?

Bonus: what would it feel like?

submitted by /u/DasBeasto
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Why should death from dehydration have to be so suffering?

Posted: 17 May 2017 07:12 PM PDT

I have heard that dying from dehydration is one of the most uncomfortable and gruesome death possible. I understand some aspects on why a person would show symptoms because it is the body's way of warning the user. However, if a person is severely dehydrated then the body should just accept that the person is probably stuck somewhere that has no water. The body should release large amount of endorphin and make the death as serene and comfortable as possible instead of having the person suffer through death.

I do not understand this from a biological standpoint since starvation has the body release endorphins after a while since it recognizes that death is inevitable.

submitted by /u/Grandtier
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What happens on an atomic scale when water is boiled?

Posted: 17 May 2017 11:55 AM PDT

So my college entry biology professor (with a doctorate) just told my summer school class that when water boils, the hydrogen and oxygen atoms split and bind to each other, forming H2 and O2. I have always been taught that water vapor is just water molecules that are heated to a gaseous form.

Also, if what he said is true (which at this point, I have trouble believing) than why does the ensuing H2 gas and O2 gas not react with my kitchen stove and blow my house apart when I do something like cook pasta?

submitted by /u/scarredFalconer
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Use of the delta function in QM?

Posted: 18 May 2017 04:44 AM PDT

I've only ever come across this function in Control Engineering for system response, however I think I remember someone in another thread mentioning its use in quantum mechanics, can anyone tell me how it is used in that field?

Thanks

submitted by /u/spk96
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[Physics] How do whispering gallery mode resonators in lasers work?

Posted: 18 May 2017 04:31 AM PDT

How do they work and how are they able to get ultra narrow linewidth, high Q factor? Links to articles, journals or books are highly appreciated. Thanks in advance.

submitted by /u/Quanta314
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how does chirality come into play when manufacturing pharmaceuticals?

Posted: 17 May 2017 10:10 PM PDT

I understand what it is I just dont get how a mirror of a molecule would come into play. are they connected? do they come in pairs and the other molecule has to be flushed out? does it just happen by accident that a molecule chiral partner slips into the mix and isnt easily spotted because of its likeness? please explain.

submitted by /u/endlessunshine833
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How does the weak force works ?

Posted: 17 May 2017 11:53 PM PDT

I manage to understand the other 3 interaction but the weak force still remains a mystery, i was wondering if you van answers these following questions: 1. What are the mechanism of the weak force ? 2. What field of boson transmit it ? 3. How does the weak force affect our lives ? 4. Can or Have we harnessed the weak force in any way ?

submitted by /u/Mikhail_Mifzal
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What makes some adhesives reusable and some useless unless reapplied?

Posted: 17 May 2017 06:53 PM PDT

In the case of sticky notes, they can be stuck several times before losing their "stick", while things like super glue stick once and never again.

submitted by /u/Unfortunate_taco
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If I aim a 'typical' laser-pointer into the night sky, assuming no clouds, how far will it travel/be detectable into space?

Posted: 17 May 2017 06:40 PM PDT

Obviously I know this depends on the sensitivity of the object "detecting it" but in general how far would a laser-pointer pointed into the sky get before it could no longer be detectable.

If it's necessary to put a metric on it "how far until the human eye would no longer notice its presence?"

submitted by /u/gett-itt
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Can swordfish see their own bill?

Posted: 17 May 2017 03:32 PM PDT

What in the human anatomy of fingers makes it easier to get a ring on than off?

Posted: 17 May 2017 11:17 AM PDT

Wednesday, May 17, 2017

Why do so many medicines require you to stop eating grapefruit?

Why do so many medicines require you to stop eating grapefruit?


Why do so many medicines require you to stop eating grapefruit?

Posted: 16 May 2017 02:03 PM PDT

Is a single atom able to cast a shadow?

Posted: 17 May 2017 03:24 AM PDT

[neuroscience]Is there any limit as to how much information that the human brain can hold?

Posted: 16 May 2017 06:58 PM PDT

Is there any theoretical limit as to how much information that the human brain can hold?

What would happen if someone reached that limit?

submitted by /u/Der_Ist
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Why is NASA's James Webb telescope built out of hexagonal panels for its mirror? Why is the mirror not a curved surface, and why were hexagons chosen over triangles or octagons etc.? Why does the Hubble telescope (seem to) not require this geometry?

Posted: 16 May 2017 10:02 PM PDT

Why is there a blip in lift at the stall angle in this CFD calculation?

Posted: 17 May 2017 03:55 AM PDT

As you can see from this image, there is a blip in lift around the stall angle for the wing we ran through a CFD program. We tested around 17-20 degrees multiple times and still saw that the lift went down, then up, then dropped off again as it stalled.

Is there a reason for the lift dropping off, then spiking again? Is it because of something to do with the flow detaching at a certain angle, then managing to reattach before detaching again? Is it just an expected error when running this sort of simulation through a computer program, or did we simply not test a wide enough range around the stall angle to get enough data to show a relatively steady drop off?

Lots of questions, I'm just puzzled as to why this happened. Any help would be greatly appreciated!

EDIT: My comment on a x-post:

Yeah, vortices being generated on the leading edge would be my guess as it's the only seemingly possible way for the flow to reattach after detaching at a slightly lower AoA, which would explain the lift spike.

The only comparable example I can come up with is the Vortex Lift effect on delta wings, which causes an increase in lift at high AoA due to vortices forming on the leading edge. However, this happens because the leading edge is sharp, so I didn't think this was possible for a ~NACA 0021 profile.

For delta wings: "In general, this vortex flow results in an increase in lift associated with the upper-surface pressures induced by the vortex and an increase in drag resulting from the loss of leading-edge suction." The effect is how delta wings maintain low speeds / high AoA as the vortices increase the stall angle.

No way of testing it, but it's a NACA 0021 profile so I thought that this effect would be well documented if it existed on the profile. The only reason I can think it might not be documented is if this effect only happens at certain airspeeds and I happened to pick one that it does happen at.

It may just be an error with the CFD calculations, or it's just such a small effect that it's not credited elsewhere.

submitted by /u/Geotherm_alt
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How do virtual photons have a real influence?

Posted: 17 May 2017 06:00 AM PDT

My question is, if virtual photons are a mathematical book keeping tool, how do they play a real role in terms of Hawking radiation and vacuum energy?

Thanks!

submitted by /u/spk96
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Has an underground nuclear power plant ever been attempted, and would having a nuclear plant under ground mitigate the problems from a meltdown?

Posted: 16 May 2017 02:36 PM PDT

Can a linear accelerator be re-configured and used as a 'decelerator'?

Posted: 16 May 2017 06:23 PM PDT

Let's say one had a beam of charged particles moving at some speed, could they be slowed using a linear accelerator that is reconfigured to decelerate the particles? If it's simpler to think about this with defined 'packets' of charged particles, or particles that penetrate the 'decelerator' one at a time, then so be it.

submitted by /u/dbcollins
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Can neutrons be created by bombarding protons with electrons of high enough energy?

Posted: 16 May 2017 10:19 PM PDT

I'm aware that electron capture is this process, but it only occurs in nuclei where there is a lower energy decay state. What I haven't been able to find information on is if it's possible to fire an electron at a proton and convert the pair into an electron neutrino and neutron via the weak interaction, provided that the electron comes in with enough kinetic energy to account for the extra neutron mass. Since a similar process can take place with neutrinos transforming protons in nuclei via inverse beta decay, can electrons do something similar to bare protons (Hydrogen)?

submitted by /u/USI-9080
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Do different types of radiation have different effects?

Posted: 16 May 2017 04:56 PM PDT

I work in a nuclear power plant and we hear a lot about radiation doses and everything we do to keep it as low as reasonably achievable (ALARA).

During our training that everyone goes through we learn about different types of radiation: alpha, beta, gamma, and neutron. The focus is primarily on their penetrating power. Alpha is stopped by paper or skin, beta is blocked by plastic or aluminum, gamma is blocked by lead, and neutron radiation is blocked by concrete.

My question is do these different types of radiation have different effects on the body or are they just classified that way according to their shielding requirements?

submitted by /u/firedragonsrule
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Do astronauts in space have to push harder, in order to have a bowel movement?

Posted: 16 May 2017 06:30 PM PDT

If someone is walking down the road, is the air around them moving to avoid the person, or are they more like a knife cutting through the air?

Posted: 16 May 2017 12:28 PM PDT

Could a binary star system have a planet tidally locked to the baricenter?

Posted: 16 May 2017 02:48 PM PDT

What kills you when you burn to death?

Posted: 16 May 2017 12:46 PM PDT

Ok so the title sounds a bit silly but my question is,

What exactly is shutting down or ceasing to function when one burns to death? Obviously burning skin probably wouldn't kill you (not quickly anyway) and pain cant kill people AFAIK

So what is the fire doing to your body that causes you to die? is it heatstroke? does the fire burn through your skin and begin directly damaging organs? i was of the understanding fire killed you long before it was able to do this.

submitted by /u/ronduun
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If humans have only been around for about 100,000 years, then why did it take 95,000 years for us to do anything rememberable? Did our brains become more evolved in the last few thousand years?

Posted: 16 May 2017 07:49 PM PDT

The first major civilizations emerged around 5,000 years ago in places like the Middle East. All of recorded history fits approximately within the last 5,000-years. That leaves 95,000 of human history with nothing happening besides changes in the types of spears we used. Where are the wars of conquests and battles between the great empires from 50,000 years ago? Things like this didn't happen because it took 95,000 years to invent agriculture? Are humans from 50,000 years ago just the same as me? It seems amazing that for 95,000 years we did nothing, and just within the last 5,000 years we have gone from cave men to developing the technology to colonize other planets.

submitted by /u/some_dude_0123
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Why does being electrocuted (high voltage) cause a person to die?

Posted: 16 May 2017 08:58 PM PDT

In conversation with friends, we decided to look this up but after numerous pages on google, the most we got was that it stops your heart.

Why does it stop your heart? What prevents a human from being able to withstand higher voltage without dying?

Edit: grammar

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Can anyone give an intuitive explanation of gauge theory?

Posted: 16 May 2017 04:25 PM PDT

Is it possible to explain it in a way which is intuitive? I'm thinking something along the lines of how gravity is "an elastic sheet", but better than that, because that's a terrible analogy...

Thanks

submitted by /u/toolemeister
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[Physics] Can you fuse elementary particles and their antiparticles together, and what happens if you do?

Posted: 17 May 2017 04:51 AM PDT

I was wondering if you can fuse the following pairs: -Quarks/Antiquarks -Gluons/Antigluons -Electrons/Positrons

Do you still get a Photon for all of them or do you get a new particle. If you get a Photon, how could you create a new particle instead of a Photon?

I'm guessing that they have to collide to release their energy as Photons.

submitted by /u/Fleeingfromhumanity
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Is there an intuitive way of understanding the contraction mapping theorem?

Posted: 16 May 2017 05:59 PM PDT

How stable would elements in the island of stability be?

Posted: 16 May 2017 03:46 PM PDT

I'm asking because its my understanding that most superheavy elements last for inconceivably short amounts of time. Is it plausible that elements in the island can exist for thousands of years, or may it only be for a few seconds at best?

Following on, is there a possibility elements in the island could occur naturally somewhere in the universe?

submitted by /u/Khwarezm
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Could someone explain these equations?

Posted: 17 May 2017 02:41 AM PDT