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Energy equation

  1. Oct 11, 2003 #1
    Hi guys,

    Just a provocative thought.

    It i said that a good theory for everything must be true in all circumstances.

    So, Why does e=mc^2 fail in this regard?
  2. jcsd
  3. Oct 11, 2003 #2


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    1+1=2 is also true in all circumstances, but it is not a theory of everything. E=mc2 was derived from Einstein using the Theory of Special Relativity. It is simply a result, it is not a theory.
  4. Oct 11, 2003 #3
    When is e=mc^2 not true?
    Last edited: Oct 12, 2003
  5. Oct 12, 2003 #4
    As Intergral said, e=mc^2 is a result of a theory and not a theory itself. Other results of General Relativity predicted its own downfall, particularly the Bing Bang, blackholes and singularities. The rules of General and Special Relativity break down in those areas and other tools are needed to understand them. Quantum Mechanics was developed to help understand these things that General Relativity could not.

    I believe the equation does implicitly say that energy and mass are different ways of looking at the same thing.

    Remember those toys called “Transformers” we all knew it was a truck, and also a robot in disguise.

  6. Oct 12, 2003 #5
    Oh yeah, black holes, always forget about those...
    On the second point you made, I apparently made an edit while you where typing your reply, because I realized your point myself, but of course it was only after I hit 'Submit'. Good example though, gotta remember that one.
  7. Oct 12, 2003 #6
    E=mc2 is violated within virtual interactions according to Heisenberg's uncertainty principle, where [del]E[del]t<h/(4[pi]).
  8. Oct 12, 2003 #7
    Loren, isn't that just a violation of energy conservation? I mean, on a short timescale there is energy that "appears" for virtual interactions as you say, but that is a violation of energy conservation. E=mc^2 more appropriately is interpreted as energy and mass have the same effect on space-time and I don't think anyone says that the temporary energy on the uncertainty time-scale "does not" have the same effect on space-time as mass would...therefore E=mc^2 would not be broken.
  9. Oct 12, 2003 #8
    another test of energy equation

    Excuse my ignorance as I am no mathamaticion in fact I didn't even pass Highschool.

    But I am under the impression that for a formula to be true it has to be able to be inverted.

    So, if e=mc^2 what does anti- energy/matter equal. How would you write an inversion of this equation? Me thinks we can't. Therefore another equation is needed to describe energy and anti-energy. And then that equation would hold true regardless of black holes or other.

    Please tell me if my approach is wrong.
  10. Oct 12, 2003 #9
    I think so, it's more of a rule of thumb and applies in mechanics, etc..
  11. Oct 12, 2003 #10

    You may be right, that E=mc2 is a physical principle unaffected by (but often appearing in) the HUP, if [del]E=[del]mc2 for all [del]E and [del]m. Regrets.


    Photons (energy) are their own antiparticle, thus the conversion of matter or antimatter to energy is indistinguishable.
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