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Thread: E=mc2 Question from a novice...:0)

  1. #1 E=mc2 Question from a novice...:0) 
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    Hi, I am new here, and love physics. I would like to know...if light is the fastest speed in our universe (670 Million miles per hour), in Einstein's formula...how can E=mc2 square the speed of light? Is that what it means, that light would have to travel 1340 Million miles per hour to change matter into energy, or vice versa? Is it saying that matter AND the speed of light together need to be squared, or just the speed of light squared? That can't be right if the fastest speed is 670Mil MPH. Can it? Is there a short answer I can comprehend? Thank you, Michel Michel


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    Moderator Moderator Markus Hanke's Avatar
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    The formula you quote has nothing to do with speeds - what it does is give a relationship between the mass of an object at rest and its energy, with the c^2 simply being a proportionality factor between the two. You can think of c^2 as merely a number. What this formula tells us is that rest mass and energy are equivalent, i.e. that mass is merely a form of energy.


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    Mass and Energy are interchangeable, the underlying abstract from which Einstein's genius pours forth. jocular
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    I never used to understand how all the units of measurement related to each other, either.

    I was like, "Calories? Density multiplied by volume? Miles per second?"

    It was all Greek to me.
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    The way Einstein found E=mc^2 was by looking at symmetry between equations. This is a very old technique for finding new theories. You take a well known theory from one area of physics and you try to match it to another area looking for gaps or symmetry. In any event if you can convert matter to energy in a number of ways. On way is through chemistry. If you burn chemicals together then tiny bits of matter are turned into energy. This is because the covalent bonds that hold the atoms together are matter. When you destroy those bonds they turn into energy. You can also destroy matter by splitting the atom. Splitting the atom is more efficient with slightly more matter converted to energy. The last way of converting matter to energy is by introducing it to antimatter. That is 100% efficient conversion. So the reason the formula is E=mc^2 has the power term ^2 relates to the shape of the atom. The energy is trapped in the area of the atom. The maths is rather pretty in that regard. You will find that the speed of light is a constant in the universe that is why it is the letter c. This means that the faster you travel the heavier you will become, the more energy you will use and the slower your time will appear relative to an outside observer. Those variables will increase so that you cant go faster that the speed of light. You cannot travel faster than the speed of light. No one really knows how to convert energy into matter. There is a famous experiment called the double slit experiment that tries to figure out when an electron is a wave (energy) and when it is a particle (mass). However the electron seems phase between wave and particle based on the observer.
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    Quote Originally Posted by uptonryan View Post
    So the reason the formula is E=mc^2 has the power term ^2 relates to the shape of the atom. The energy is trapped in the area of the atom.
    You were doing fine up until then.

    There is a famous experiment called the double slit experiment ...
    I'm not sure how that is relevant to either e=mc2 or the speed of light ...
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    You were doing fine up until then.
    yeah words fail me a bit. I guess what I am trying to say is explained very well in this document. http://www.nscl.msu.edu/files/Benenson.pdf The double slit experiment is relevant because the OP wanted to know how to convert mass into energy and energy into mass. That is also known as wave particle duality which is the double slit experiment. Sorry if I did not make that clear.
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    Quote Originally Posted by uptonryan View Post
    You were doing fine up until then.
    yeah words fail me a bit. I guess what I am trying to say is explained very well in this document. http://www.nscl.msu.edu/files/Benenson.pdf
    Despite the fact that that document is appallingly badly written and uses MS Comic Sans it seems reasonably accurate. But it doesn't say anywhere that "the power term ^2 relates to the shape of the atom. The energy is trapped in the area of the atom." So I wonder where you got that from.

    The double slit experiment is relevant because the OP wanted to know how to convert mass into energy and energy into mass. That is also known as wave particle duality
    How do you relate the wave-particle nature of quantum scale objects to mass-energy equivalence?
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    So I wonder where you got that from
    It is a very complex notion. It falls out the maths. If you have an electron travelling at speed c trapped by an atom then that electron will fill an orbit of that atom. Lets say it is hydrogen to be easy. The key is to assume that the electron does not slow down. The electron stays at speed c. If you do the mathematics it turns out you have the volume of the atom divided by the area of the orbit of the election. The c^2 term drops out and this relates to the area that the electron occupies in orbit.
    How do you relate the wave-particle nature of quantum scale objects to mass-energy equivalence
    A wave is energy. Energy is a wave. Particles are mass.
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    Utter rubbish! It falls out of no maths I've ever seen, it appears to have fallen out of your backside.
    Surely you are not asking me to replicate the maths here? Atomic orbital - Wikipedia, the free encyclopedia Neil Bohr developed a very simple model of a hydrogen atom early on. However that model has been shown to be coincidental. The reality has incredibly complex integrals and probabilities. Still the fact remains that the c^2 term drops out of the area orbital of the electron around the atom. Prove me wrong. Are you saying the orbit of the electron is not proportionate to the energy ?
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    Quote Originally Posted by uptonryan View Post
    It is a very complex notion. It falls out the maths. If you have an electron travelling at speed c trapped by an atom then that electron will fill an orbit of that atom. Lets say it is hydrogen to be easy. The key is to assume that the electron does not slow down. The electron stays at speed c. If you do the mathematics it turns out you have the volume of the atom divided by the area of the orbit of the election. The c^2 term drops out and this relates to the area that the electron occupies in orbit.
    I will be politer than PhDemon and just say: citation needed.

    A wave is energy. Energy is a wave. Particles are mass.
    Er. No. Photons are particles (and waves, as much as electrons or anything else) and have no mass.
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    Quote Originally Posted by uptonryan View Post
    Still the fact remains that the c^2 term drops out of the area orbital of the electron around the atom.
    The derivation of the mass-energy equivalence formula has nothing to do with electron orbitals. The formula e=mc2 is incomplete by the way, how does your math account for the full form of the equation?

    Prove me wrong.
    Oh dear. The rallying cry of the crackpot. Don't be that guy.

    How can you be proved wrong when you have not presented any math. You appear to have made up an idea which is not based on any known science and is not supported by any evidence or theory.

    Please feel free to "prove yourself right" by providing some references to support this.
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  14. #13  
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    Quote Originally Posted by uptonryan View Post
    Surely you are not asking me to replicate the maths here? Atomic orbital - Wikipedia, the free encyclopedia
    Please show where that page says that e=mcs is due to the "area of the orbital". Or even that all electrons are travelling at c. Or any of the stuff you have made up.
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    Please show where that page says that e=mcs is due to the "area of the orbital". Or even that all electrons are travelling at c. Or any of the stuff you have made up.
    Ok speed of electron is c as per Speed of electricity - Wikipedia, the free encyclopedia the speed of an electromagnetic wave in a vacuum is c. An electron travelling around an atom is travelling in a vacuum. The relationship between e = mc ^2 and the area of the orbital is described Neils Bohr model of the hydrogen atom and in the link I posted. I think this link shows some math Bohr model - Wikipedia, the free encyclopedia lastly photon is a special particle without rest mass.
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    Judging by the shocking ignorance on display so far I'm guessing no
    If you cant win the argument attack the person right? I have honour in Electrical Engineering a Masters in Business and a law degree. I will accepted they are not peer reviewed articles and that this is a rather controversial area of physics. However that fact remains that there is a relationship between orbitals of the atom and E=mc^2. How can there not be? I don't understand why you disagree so violently?
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    Quote Originally Posted by uptonryan View Post
    Please show where that page says that e=mcs is due to the "area of the orbital". Or even that all electrons are travelling at c. Or any of the stuff you have made up.
    Ok speed of electron is c as per Speed of electricity - Wikipedia, the free encyclopedia the speed of an electromagnetic wave in a vacuum is c.
    Which has nothing to do with your claims.

    An electron travelling around an atom is travelling in a vacuum.
    But is an electron, not an electromagnetic wave. (That would be a photon.)

    The relationship between e = mc ^2 and the area of the orbital is described Neils Bohr model of the hydrogen atom and in the link I posted.
    No it isn't. If you think it is, why not copy the appropriate text.

    I think this link shows some math Bohr model - Wikipedia, the free encyclopedia
    It does show "some math". But nothing that agrees with what you said. In fact, it says, "The Bohr model gives almost exact results only for a system where two charged points orbit each other at speeds much less than that of light." Which directly contradicts what you said.

    Oh, and the Bohr model is wrong.

    You seem to be just picking random links to support what you said. Why not just tell us where you got the "c^2 relates to the area of the atom" stuff from?

    lastly photon is a special particle without rest mass.
    Which directly contradicts what you said earlier.
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  18. #17  
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    Quote Originally Posted by uptonryan View Post
    this is a rather controversial area of physics.
    Except that it isn't.

    However that fact remains that there is a relationship between orbitals of the atom and E=mc^2. How can there not be? I don't understand why you disagree so violently?
    Because you are wrong. You are unable to provide a reference that supports what you say. And you may confuse other readers of the forum.
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  19. #18  
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    For anyone interested in learning more (which appears to exclude ryan) the derivation of the mass-energy equivalence can be found here: Mass–energy equivalence
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    But is an electron, not an electromagnetic wave
    An electron can be both a wave and a particle. This was discovered by Einstein in a famous experiment called the Photoelectric effect Photoelectric effect - Wikipedia, the free encyclopedia
    Oh, and the Bohr model is wrong.
    Do you know who Bohr is?
    Because you are wrong. You are unable to provide a reference that supports what you say. And you may confuse other readers of the forum.
    I'm referencing Wikipedia? where are your references?
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    Quote Originally Posted by uptonryan View Post
    But is an electron, not an electromagnetic wave
    An electron can be both a wave and a particle. This was discovered by Einstein in a famous experiment called the Photoelectric effect Photoelectric effect - Wikipedia, the free encyclopedia
    No, that was about showing that photons are particles.

    But yes, of course electrons are waves and particles. Everything is. But electrons are not electromagnetic waves.

    Do you know who Bohr is?
    Of course. The Bohr model is still wrong.

    I'm referencing Wikipedia? where are your references?
    Nothing you have referenced supports what you say. Much of it contradicts you (because you are just making stuff up). I have provided references where you can find more accurate information. Or you can look in any standard textbook. You can also choose to ignore it and remain ignorant. I don't really care.
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    Quote Originally Posted by PhDemon View Post
    [
    You have no argument, just ignorance (as your later posts which Strange has responded to make abundantly clear). Engineering (and some other irrelevant nonsense) eh? You obviously know no chemistry or physics which is part of the problem. Your alledged competence in one sphere doesn't mean you know what you are talking about here which you evidently don't. Even a first year undergrad in chemistry or physics would spot your bollocks for what it is. There is NO relation at all between E=mc2 and energy levels in atoms, none at all. This is why I disagree, utter stupidity tends to make me more vocal about disagreements.
    From outside of the confines of this conversation, it looks to me as though you are addressing an inability to understand as "stupidity". Is that the case? joc
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    This is probably a silly question, but if we were in a Universe with 4 spacial dimensions, would the equation be "E=mc3"?
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    This article explains electrons and electromagnetic waves fairly well X-ray (radiation beam) -- Encyclopedia Britannica
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    I am shocked that a teacher would be so abusive. Any teacher calling students stupid should be fired immediately. Kinda makes me feel you are not really genuine. Your argument is with Niels Bohr and Einstein not with me. I will leave you to it.
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  26. #25  
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    The relation in question is a special case of a somewhat more general result, being the norm of the energy-momentum 4-vector in Minkowski space-time. That vector norm turns out to be



    If the system in question is at rest in the observer's frame, this reduces to the simple E=mc^2; for massless particles such as the photon it reduces to E=pc. In either case, the relation is actually a result of geometric considerations coupled with the basic fact that 4-velocity and 4-momentum must be related via P=mU.

    The relation can be derived using other arguments, and I don't doubt that quantum mechanics might yield it as well, but it doesn't rely on that fact to be true.
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  27. #26  
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    Quote Originally Posted by Daecon View Post
    This is probably a silly question, but if we were in a Universe with 4 spacial dimensions, would the equation be "E=mc3"?
    No. In a universe with 4 spatial dimensions only, this relation between energy and rest mass would not exist at all. One can still form the norm of the momentum 4-vector, but its P(0) component would not contain any reference to energy, only to spatial momentum. So E=mc... wouldn't be valid in such a universe.

    P.S. It is not a silly question at all, in fact it is quite non-trivial.
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    I'd rather you just stopped posting bollocks
    Well show me your mathematical proof for the shape of the electron cloud? Can you do that or do you just hurl abuse. If you know what you are talking about then you should be able to derive the shapes of the electron clouds in atoms from first principles. If you cant do that then you obviously have no credibility whatsoever.
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    Your opinion of my crdibility means less than a fart in a hurricaine as it is obviously uninformed.
    Hey man hate the game not the player. If you cant do it, then you cant do it. The fact you think its a waste of time makes me wonder about you interest in science.
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    So you calling me
    another ignorant internet nutjob
    was said with love? Its actually fun to get into the maths. You are missing out by not doing it. However I understand your lack of interest.
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    MODERATOR INTERVENTION : This thread is starting to go into the wrong direction; I need everyone to take a deep breather and calm down a little, please. In particular, the name calling stops here and now, or else I will have no choice but to start imposing sanctions.
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    I think he is talking about you Markus
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  33. #32  
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    Quote Originally Posted by PhDemon View Post
    Sorry Markus, but the intellectual laziness of people who think making stuff up is a substitute for education really annoys me.
    I understand where you are coming from, but as a moderator I need to intervene once things become too heated. No harm done, so long as the discussion proceeds in a civil manner.
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  34. #33  
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    Quote Originally Posted by Markus Hanke View Post
    Quote Originally Posted by Daecon View Post
    This is probably a silly question, but if we were in a Universe with 4 spacial dimensions, would the equation be "E=mc3"?
    No. In a universe with 4 spatial dimensions only, this relation between energy and rest mass would not exist at all. One can still form the norm of the momentum 4-vector, but its P(0) component would not contain any reference to energy, only to spatial momentum. So E=mc... wouldn't be valid in such a universe.

    P.S. It is not a silly question at all, in fact it is quite non-trivial.
    Ah, I see. Well, I don't quite understand some of the terminology, but I get the jist of it.

    The reason I asked was because I thought I'd heard that gravity follows an inverse-square law with 3 spacial dimensions, and an inverse-cube law with 4 spacial dimensions (unless I'm mis-remembering) and was curious if it was a similar pattern.
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