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Quantum mechanics and the speed of light

  1. Nov 9, 2008 #1
    in hydrogen atom we write:
    then for r < (ke^2)/mc^2
    the speed of electron must be fast than light to be in this area.
    but in quantum mechanics we have some probbility to be there.

    thus in quantum mechanics we have some probbility to have speeds big than light.

    is this true?
  2. jcsd
  3. Nov 9, 2008 #2


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    Because electrons are not small balls "orbiting" the nucleus, your first equation is simply not applicable.
    You can't use classical physics to describe quantum mechanical phenomena.
  4. Nov 9, 2008 #3
    The equation you are using is from nonrelativistic classical physics, and so has nothing relevant to say about speeds being less or greater than c, nor does your conclusion have anything to do with QM.
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