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Thursday, March 2, 2017

What would be the implications if the existence of a magnetic monopole was found?

What would be the implications if the existence of a magnetic monopole was found?

What would be the implications if the existence of a magnetic monopole was found?

Posted: 01 Mar 2017 11:27 AM PST

I know from university physics that thus far magnetic poles have only been found to exist in pairs (i.e. North and South poles), yet the search for isolated magnetic pole exists. If this were to be found, how would it change theoretical physics?

submitted by /u/thenumnum1429
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When a star collapses to a neutron star it's said that the electrons crash into the nuclei, specifically into the protons, to form neutrons, so do they combine with an up quark to for a down quark or how do I have to imagine this process?

Posted: 02 Mar 2017 06:53 AM PST

The all-green picture with "red" strawberries picture. Do I see red because I know ripe strawberries are red?

Posted: 02 Mar 2017 07:42 AM PST

This picture seems to be popular this week:

https://i.redditmedia.com/BU23cX5feW7AjHZKnS69Dio9QWDurnRb6A3vx9XZojo.png?w=1024&s=c99d09cef7f72ae2f40c3ae63fd1e53c

If you were to ask someone who has never seen strawberries before, would they still say they look red? (i.e: am I "seeing" red because I know strawberries are red?)

submitted by /u/might_be_a_troll
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Would stars be visible from the daylit side of Ganymede?

Posted: 02 Mar 2017 02:38 AM PST

I just got finished watching the most recent episode of "The Expanse" and part of the action takes place on the surface of Ganymede. As the camera follows the action, in the background you can see the stars above the horizon, but it's pretty clear that the action is taking place during the day.

My question is, is daylight dim enough on Ganymede so that the stars would still be naked-eye visible? or is it still bright enough like our own moon where adjusting cameras to image the surface (and presumably our own eyes) renders the stars invisible?

submitted by /u/millijuna
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How can the electromagnetic and weak interactions be unified, if they have different gauge bosons?

Posted: 02 Mar 2017 12:01 AM PST

The electromagnetic interaction is carried by photons, while the weak interaction is carried by W and Z bosons. How can it then be that these two forces are in fact the same force, the electroweak interaction?

submitted by /u/marcelgs
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How can photons not have mass?

Posted: 01 Mar 2017 11:02 PM PST

I thought that everything in the universe had mass in some form or another. So why is it that photons don't have mass?

submitted by /u/Baxtrus
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Why did it take so much longer to discover the Higgs boson compared to other fundamental particles in the Standard Model?

Posted: 01 Mar 2017 09:18 PM PST

I have high-school level knowledge of basic particle physics, and I think I know that the Higgs boson's interactions with particles more or less "give them mass," but I know that's an overly simplified explanation and that the exact interaction is probably way more complicated.

submitted by /u/whitenedblink
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Why can carbon form four covalent bonds when the 2s orbital is paired up leaving only 2 solo electrons in the 2p Orbital?

Posted: 01 Mar 2017 09:14 PM PST

What are some practical applications of pulsars?

Posted: 02 Mar 2017 12:16 AM PST

Why doesn't FTL quantum tunneling violate causality?

Posted: 01 Mar 2017 08:39 AM PST

It seems that a bunch of experiments confirmed that particles tunnel through barriers faster than what would be expected if they were traveling normally at the speed of light. I'm referring to a study specifically by the Keller group in 2008 but this seems to be the consensus today (according to Wikipedia at least).

I'm not ready to believe that relativity would fail so quickly and I'm inclined to think that even if FTL tunneling is possible, it wouldn't allow FTL communication. But I fail to see how that's the case.

edit: corrected group name to 'Keller group'

submitted by /u/zeitouni
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Are some people more psychologically prone to developing a phobia or PTSD?

Posted: 02 Mar 2017 02:02 AM PST

I'm wondering if any environmental or genetic factors are known to influence the likelihood that someone will develop a phobia or PTSD?

There have been instances in my life that where others may have developed a phobia or anxiety, I developed none.

Examples:

  • Attacked by a violent dog. Required stitches, left a scar where hair won't grow. Yet I have no fear of dogs in fact I love them.

  • Nearly drowned in the ocean and only survived because somebody noticed me struggling and pulled me out. Left me with a respect for the ocean but no phobia.

  • Was attacked by an intruder in the middle of the night, leaving me black and blue, but I have no trauma/anxiety from this.

Others I have spoken to who experienced the same things have told me they developed a phobia or PTSD for which they sought therapy.

submitted by /u/MyRandomQuestions
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Although past menopause women no longer release eggs, are their wombs still capable of rearing babies?

Posted: 01 Mar 2017 01:34 PM PST

I mean, if you give them the right hormones to create the endometrium and other things, then deposit the baby in, couldn't they technically still carry the baby full term?

submitted by /u/TheCaptainCog
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If the ozone layer was obliterated by a gamma radiation burst, how long would it take to return to normal levels?

Posted: 01 Mar 2017 04:22 PM PST

Would any plant or animal species be capable of adapting to something like that?

submitted by /u/sericatus
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How does the adaptive immune system fight off new variants of pathogens, if there're no existing B or T cells with antigen receptors that can detect them?

Posted: 01 Mar 2017 12:42 PM PST

How does an internet server know at what speed to transmit you data?

Posted: 01 Mar 2017 10:40 AM PST

Chances are your internet connection is much slower than any server's where you're downloading stuff from. So what happens if the server "floods" you by trying to send data at a faster speed than you can download? Is that extra data lost and resent? Is it stored somewhere? Or does the server 'test' your internet connection and then sends data at a slower rate?

submitted by /u/giu989
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If we forget everything, what do we remember?

Posted: 01 Mar 2017 03:49 PM PST

This might not be accurate, but in movies and TV shows, you sometimes see a character forgetting "everything," yet saying they "don't know who [they] are." If we purportedly forget everything, then how can we still recall the idea of identity?

submitted by /u/krismjenner
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Could you electrically charge mercury and place it in a insulated water gun then shoot someone and electrocute them?

Posted: 01 Mar 2017 03:22 PM PST

I asked my high school teacher and looked this up as it popped into my mind during class but was left empty handed. Thanks for any insight you can share on this!

submitted by /u/ImBetterAFK
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Can erbium be used to stop a nuclear reaction?

Posted: 01 Mar 2017 07:23 AM PST

I saw on periodicvideos that erbium is a nuclear poison. It was described as killing any nuclear fission dead. If that is true, at what scale can it do this. Is it possible to produce a sort of safety kill switch for nuclear reactors? Or is the amount of erbium required just too massive? Or is there a reaction that makes this unfeasible? I had never heard of a nuclear poison before.

submitted by /u/MrZerbit
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Why isn't there a ciritical point on the solid-liquid phase boundary?

Posted: 01 Mar 2017 07:11 AM PST

On the liquid-gas phase boundary of pure substance there is a critical point above which the liquid phase and the gas phase become indistinguishable. Why doesn't the same happen on the solid-liquid or solid-supercritical fluid phase boundary?

I remember this being a possible question in the oral exam for one of my practical courses in physical chemistry. In preparation for the exam my lab partner and I asked dozens of other students and phd students. No one was able to give a satisfying answer.

Luckily we weren't asked in the exam, but afterwards we went on and aksed the prof on that subject. His answer was that the phase change solid-liquid is mainly determined by a change of order in the substance. In contrast to that the liquid-gas phase change is determined by the change in interaction of the particles and overcoming of the attracting forces. I found that to be a pretty disappointing, undetailed answer.

submitted by /u/N3uroi
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How does a GPS calculate the shortest distance between destinations so fast?

Posted: 01 Mar 2017 02:36 PM PST

Maps have a subtle depth to them where each intersection has its own rules like no right turns, and certain roads only go in one direction. How did they go about writing an algorithm that takes all of this into account?

submitted by /u/joev714
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Is it possible to see a Mars Exploration Rover moving around on Mars from Earth? Is there any footage of this?

Posted: 01 Mar 2017 12:50 PM PST

Can I take a protein sample (for DNA Extraction/ PCR) without killing the fish?

Posted: 01 Mar 2017 10:50 AM PST

Using this kit to catalog the genetic barcodes of trout from various lakes and I wanted to avoid having to kill a bunch of fish.

Thanks!

submitted by /u/Intimatepandas
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Wednesday, March 1, 2017

Is there any culture (current or past) that doesn't honor their dead?

Is there any culture (current or past) that doesn't honor their dead?

Is there any culture (current or past) that doesn't honor their dead?

Posted: 28 Feb 2017 09:18 PM PST

How does our bodies deal with pollutants in air? And how does micro dust particles effect our bodies?

Posted: 28 Feb 2017 09:50 PM PST

Why aren't solar panels mounted on wind turbine towers?

Posted: 28 Feb 2017 09:14 PM PST

My thoughts so far:

A 3 MW wind turbine tower (ca. 5.000 kWh / year) is 100 m tall and about 5 m wide. It should be possible to mount about 500 m2 facing east to west with a 45° mounting angle to produce roughly 50 kWh / year in northern Germany (where I am) up to 100 kWh / year in Texas (I used an online calculator and tried to maximize output by changing locations). So only 1% - 2% solar in comparison to wind.

Pros

  • no extra land needed

  • very little shadows on the panels

  • electrical installations are mostly (?) already in place

  • low installation cost, as the towers are produced en masse and in factorys

  • slightly higher grid stability (when the wind blows and it's overcast / when the sky is clear and it's calm) (also solar should be able to produce at least more than the 1 - 2% of wind stated above, since thats per annum and in reality solar produces power only half of the day -> 2 - 4% ?)

cons

  • vertically mounting solar panels reduces efficancy by roughly 35% (but panels could be mounted at an angle)

  • maintenance difficulty due to hight

  • wind puts high stresses on panels

submitted by /u/ryebow
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How does the Doppler shift of light waves affect the photoelectric effect in metals?

Posted: 01 Mar 2017 06:11 AM PST

I had this thought today: suppose we positioned a light source and metal surface in space facing each other - the light has a frequency below that of the threshold frequency of the metal. If we were to cause relative motion between the two (for e.g. Moving the source towards the metal at a high speed) so that the light was blue shifted such that its frequency exceeded the threshold frequency, would the photoelectric effect now be observed?

submitted by /u/axxenmardok
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Why does gallium make aluminum brittle and does this phenomenon occur in other materials?

Posted: 28 Feb 2017 08:07 PM PST

When the liquid metal, gallium is poured on aluminum, it somehow binds with the aluminum and makes it incredibly brittle. I'm talking like saltine crackers brittle. Why does this happen and is aluminum vs gallium the only instance of this phenomenon?

submitted by /u/Fireheart318s_Reddit
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Ask Anything Wednesday - Economics, Political Science, Linguistics, Anthropology

Posted: 01 Mar 2017 07:05 AM PST

Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Economics, Political Science, Linguistics, Anthropology

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!

submitted by /u/AutoModerator
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Is there a theoretical maximum for how fast a propeller can turn in water, yet still be effective?

Posted: 28 Feb 2017 06:33 PM PST

If a propeller were rotating under water, at some point would the RPM be so great that it moves more quickly than the water can fill the "gap" behind it?

Or perhaps, is there some kind of theoretical upper limit as to how much force can be generated from the RPM of the propeller?

Or, is there some speed at which the kinetic energy produced by the propeller boils the water, possibly causing any loss of effectiveness? (if that's even possible).

I would be really interested in learning about the fluid dynamics that are going on here.

submitted by /u/Kenny_log_n_s
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Does the photon sphere around a black hole actually contain a significant number of photons? Or do they all decay into unstable orbits?

Posted: 28 Feb 2017 06:23 PM PST

I'm not sure if I'm misunderstanding the concept here but photons can exist in a 'straight' spacetime path at 1.5 times the Schwarzschild radius? But if on one side of the black hole there is slightly more particles than on the other then wouldn't they warp the Schwarzschild radius at that specific point enough so that the photons in the photon sphere would require a slightly different energy to stay in orbit?

Does the photon sphere actually exist? Maybe I'm misunderstanding the math but wouldn't it be extremely easy to disrupt the orbit?

submitted by /u/Lost4468
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Why does Pythagorean's theorem work?

Posted: 28 Feb 2017 03:37 PM PST

Is there a way to intuitively understand why a2 + b2 = c2? I've known this formula most of my life and never understood how it works out.

submitted by /u/SoulOfAMachine
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How deep could a human go under water and still use a snorkle?

Posted: 28 Feb 2017 07:45 PM PST

At what point does the air pressure exceed the exhale pressure of a typical human? Meaning spent air could not be expelled to make room for fresh air.

Would the pressure keep you from inflating you lungs before you reach this depth? Or would your body be crushed?

Assume the snorkle doesn't buckle or crumple under pressure.

submitted by /u/mogulman31
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Does the higgsfield interfere with the conservation of momentum on massive objects?

Posted: 01 Mar 2017 05:59 AM PST

Wouldnt the higgsfield slow down fast moving objects like the "Starshot" spacecraft if it moves at 0.2c? As the higgs interaction gets stronger the more i boost particles?

submitted by /u/Trollimperator
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Is there a mechanism for gross movement of electrons or atoms to raise the energy levels of bound electrons?

Posted: 01 Mar 2017 01:40 AM PST

I understand that through the photoelectric effect an photon with a higher than ionization energy can be converted into a freed electron with the amount of higher than ionization energy showing up as electron velocity, but does that work the other way?

If 2 atoms, both with electrons in their ground states "bump" into each other, can some of that kinetic energy be converted into the either atom's electrons being in a higher energy state?

submitted by /u/UncleDan2017
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Why were there no alternative interpretations of Rutherford Gold Foil Experiment?

Posted: 28 Feb 2017 09:50 PM PST

While Rutherford's interpretation is intuitive, other interpretations could have been possible. Were there other interpretations, and if so, how were they disqualified in favor of Rutherford Atomic Model?

submitted by /u/sudhu28
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If fusion requires energy and releases even more energy, would the fusion products require energy to separate or would they naturally decay? [physics]

Posted: 28 Feb 2017 02:08 PM PST

Electron is accelerated in electric field: How are excess energy and momentum accounted for?

Posted: 28 Feb 2017 02:53 PM PST

Hi,

say an electron is passing through a capacitor with an applied dc voltage in a cathode ray tube. The electron is accelerated onto one of the capacitor plates and hence gaining energy and momentum. How is this accounted for in the electric field? Does the electric field get weaker? If so, why and how?

I am also asking related to nonlinear optics. Here, one often speaks of the electric field of a laser pulse which is accelerating electrons (and then issuing second harmonic generation and all that). Does the electric field of the laser pulse then gets weakened? I find that hard to imagine, although the excess energy and momentum of the electron have to come from somewhere.

Thanks!

submitted by /u/nonicknamefornic
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An object falling at terminal velocity is accelerated. The force stops. Does the object slow and return to its terminal velocity and of so, what force is causing this deceleration?

Posted: 28 Feb 2017 08:33 PM PST

Why is alcohol so associated with male violence when it is supposed to lower testosterone?

Posted: 28 Feb 2017 08:17 PM PST

I've stated the relationship crudely here and am probably missing nuances.

Alcohol is associated with all kinds of forms of violence, especially with young men- bar fights, rape, murder, not to mention reckless "testosterone driven" acts like drag racing. But it is supposed to put a damper on testosterone as well. Why doesn't alcohol inhibit testosterone enough to prevent people, especially young men, from doing these things?

submitted by /u/Name2522
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If a free proton and electron combined to produce a Hydrogen atom, is it formed in its excited state?

Posted: 28 Feb 2017 07:35 PM PST

What would a collision between a star and a planet look like?

Posted: 28 Feb 2017 08:55 AM PST

In the event that an Sol-sized star and an Earth-sized planet crashed directly into each other, what would the resulting impact look like?

  • Would it appear that the star simply absorbed the planet?
  • Would the impact cause a visible (from 1 au) explosion?
  • Would there be any long-lasting change to the star?

I assume a head-on collision to avoid complications of the planet breaking up due to tidal forces in orbit, turning into a ring, etc - This planet is simply plowing into the star.

submitted by /u/elongata
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What would be the "reaction" to gravity's "action"?

Posted: 28 Feb 2017 06:09 PM PST

So I just wanna start by saying I'm in no way a science-y person. I've always beeen a very curious person and I'm really fond of knowledge and constantly trying to learn new things, and I thought for a long time that I loved science, until I took high school chemistry and found out that I don't really care much for the scientific method. So my science knowledge doesn't go much farther than a high school level, but my curiosity is still high, and thus I was wondering:

Newton states in his third law of motion that "every action has an equal reaction" (obviously paraphrased but you get the idea). So if in this case, gravity is our "action", what would be the "reaction"? What acts in the other direction (up?) andmaintains us in balance enough to not be crushed by the force of gravity

submitted by /u/GuitarHeroJohn
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Are there infinetly many prime numbers?

Posted: 28 Feb 2017 02:46 PM PST

Are the prime numbers infinite or is there a point on which the numbers get so big it that the propability of them being prime is as good as zero? Because when the numbers get bigger the prime-frequenty gets lower so is there a point where this reaches zero?

submitted by /u/BlazingMetal
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[Mathematics] Does any succesive application of roots have a limit?

Posted: 28 Feb 2017 02:23 PM PST

As in, if you get the square root of the square root of the square root of the square root... of a number. Does it ever approach anything or does it get arbitrarily close to zero? Also, if you get the nth root of a number, and then take the n+1th root and then the n+2th, and so on. Do these operations ever converge to some value? I'm a fan of math but don't really know much about calculus and such, so if the answer is complicated, I'd appreciate the usage of layman terms.

submitted by /u/PM_ME_YOUR_DICK_____
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Are there any fluids that can exist in a vacuum?

Posted: 28 Feb 2017 07:04 AM PST

A gas would immediately dissipate, and a liquid would boil and dissipate. Even mercury at the top of a manometer is under it's own vapor pressure. Are there any fluids that hold together?

submitted by /u/AtHomeToday
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Tuesday, February 28, 2017

Quantum Mechanics and Classical Physics: What lies in the middle?

Quantum Mechanics and Classical Physics: What lies in the middle?

Quantum Mechanics and Classical Physics: What lies in the middle?

Posted: 27 Feb 2017 06:34 PM PST

If quantum mechanics helps physicist to describe nature at the atomic level (eg. subatomic particles) and classical physics helps physicist describe nature at a macro level (eg. celestial bodies) is there a point at which one can use both to describe or calculate for something? What is the smallest thing we can describe using classical physics and what is the largest thing we can describe using quantum mechanics? Does something like that even exist? Or does the opposite exist, where one can't describe something using quantum mechanics or classical physics?

submitted by /u/cunalatamarco
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Why can our eyes precisely lock onto objects, but can't smoothly scroll across a landscape?

Posted: 28 Feb 2017 04:54 AM PST

Is the sun perfectly round?

Posted: 28 Feb 2017 04:13 AM PST

I was watching sunrise this morning through very dense fog, and the sun appeared as a perfectly round circle. Is the sun actually a perfect sphere or is it somewhat oval, etc

submitted by /u/RainbowSixSWAT
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[Astronomy] Excluding polar regions, can planet have a night and day that are not equal in length?

Posted: 28 Feb 2017 06:43 AM PST

Nighttime and daytime are not exactly equal but it's very close at the equator. Is it possible for the planet to slow down somewhat while rotating to give each cycle significant differences.

submitted by /u/CarmakazieCthulhu
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Do people bleed slower in space?

Posted: 27 Feb 2017 11:08 PM PST

My limited understanding would lead me to guess that the blood vessels are still applying pressure that would force the blood out, even in a zero gravity environment. But does the lack of pressure from gravity cause the pressure to be substantially less? I remember reading that blood pressure in general is lower in space.

submitted by /u/PopoSama
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In the post red giant stage of a star, why do the outer layers drift into space and not collapse onto the white dwarf?

Posted: 27 Feb 2017 03:37 PM PST

How do centipedes sense moisture?

Posted: 28 Feb 2017 06:18 AM PST

I assume they do because I've found them in crazy places they would never otherwise be - I never saw any in my house until I ran a humidifier in my daughter's room for a day or two, then we found two in her room. Once I had a cup of water next to my bed and the next morning there was a centipede in it (different house). And of course I think it's well known that they lurk in showers and damp basements and garages. I'm terrified of those guys and if there's a way to keep them away from me without bug-bombing my living space I'd love to hear it.

submitted by /u/mandyvigilante
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How do spacecraft get rid of excess heat?

Posted: 28 Feb 2017 12:13 AM PST

I've read the wiki article as a start but finding visuals would also be nice.

Are there also hypothetical methods of venting heat in space that we currently don't have the technology for?

submitted by /u/AndyLC
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Is there a sonic boom equivalent in water?

Posted: 27 Feb 2017 02:21 PM PST

Why is vision grainy at night or in dark areas?

Posted: 27 Feb 2017 03:12 PM PST

At night time why does human vision appear grainy?

submitted by /u/polonium2000
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Why is Jupiter too small to become a star but Trappist-1 is a star despite being the same size?

Posted: 27 Feb 2017 03:28 PM PST

Over the years I've read about how Jupiter is like a mini star that never grew large enough to form and make our system a binary. However, my understanding is that Trappist-1 is a brown dwarf that's the same size as Jupiter so how did it form?

If it was originally a larger star that shrunk then why didn't it swallow the other planets near it when it was bigger?

submitted by /u/Ellers12
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Do GPS Satellite s need to know their exact distance from the surface of the earth?

Posted: 28 Feb 2017 05:14 AM PST

How is the speed of a space probe measured?

Posted: 27 Feb 2017 01:01 PM PST

We often hear that "probe A" is leaving the solar system at a speed of XXX km/h with a very specific speed. But if I remember my science courses correctly speed is always relative to something. And that something moves in space (e.g. the Earth moves around the Sun, the Sun moves in the Galaxy etc.). Shouldn't this influence the speed given for a probe (or even a space rocket)?

Thank you for your answers !

submitted by /u/ModoZ
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How is it possible that the behavior of light can be explain by both waves and particles?

Posted: 27 Feb 2017 05:58 PM PST

Since waves and particles have different properties, how is it that light can be identified as both?

submitted by /u/JustKeepDoing
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What would happen to a flame if the ambient temperature was the same as the flame?

Posted: 27 Feb 2017 02:27 PM PST

So in a normal combustion the flame points upward because hot air rises, what would happen if the ambient temperature was the same as the flame with no external factors. What would the flame do?

submitted by /u/Matrixhammer
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Is there a limit to possible telescope resolutions?

Posted: 27 Feb 2017 01:31 PM PST

Telescopes in space are becoming better and better. I wonder if there is any limit to the detail an image of a distant object can have? Leaving problems caused by an exoplanet's atmosphere and too much light from a nearby star beside - would it theoretically be possible to get a detailed image from an object (like an exoplanet) lightyears away? Or does anything about light limit the available detail on a far distance?

submitted by /u/SmireGA
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Did cosmic background radiation light up the whole universe?

Posted: 28 Feb 2017 03:13 AM PST

If cosmic background radiation started off as short wavelength radiation, and is now radio/microwave radiation, was there a time when it was visible light and the whole universe had a background glow?

submitted by /u/patch47000
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How to derive the Relativistic Doppler shift in Energy?

Posted: 27 Feb 2017 02:21 PM PST

In his paper "On the Electrodynamics of Moving Bodies" Einstein presents a derivation of the doppler effect on light energy by first deriving the change in amplitude. After that imagines a plane wave of light, moving in the universe at an angle from the x-axis. He then imagines an imaginary sphere moving with the light in one frame of reference, such that the sphere always encloses the same 'bit' of light. He applies the Lorentz Transformation to the sphere, obtaining an equation for an ellipsoid in the other frame of reference. By multiplying the ratio between volumes by the ratio between amplitudes he gets the ratio between the energy of the light in both frames of reference. The problem is I have no idea how to take the volume of the ellipsoid. Anyone know how to do it or another easier way of finding the energy ratio (without Planck's constant)?

submitted by /u/isnar000
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Do electrons move at Absolute zero?

Posted: 28 Feb 2017 02:28 AM PST

Is there a top speed to the expansion of the Universe?

Posted: 27 Feb 2017 01:31 PM PST

It is evident that the universe is expanding and this process is accelerating. My questions are thus; 1) What is causing the acceleration of the expansion of space-time, and 2) Is there a point when the expansion speed will exceed the speed of light, perhaps causing stars and other sources of light to vanish from the sky?

submitted by /u/Obversus
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