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Ehrenfest theorem and Heisenberg quantum mechanics

  1. Feb 4, 2009 #1
    Wich are the differences between the theorem of ehrenfest and the heisenberg's rappresentation of quantum mechanics?
    Last edited: Feb 4, 2009
  2. jcsd
  3. Feb 4, 2009 #2
    The Ehrenfest theorem states what are the equation of motion for the mean value of observables like Position and Momentum

    The Heisenberg picture moves the time dependence of the system to operators instead of state vector. So it provides the equation of motions for the operators not for their mean value over a state. In Heisenberg picture there is no more need of a Schroedinger equations (for the state vector) because it is now substituted by the Heisenberg equation of motions (for the operators).
  4. Feb 4, 2009 #3
    yes i know, but my question is to be intended in differrent manner. is the theorem of ehrenfest a consequence of the equation of motion of heisenberg or they can be differents?
  5. Feb 4, 2009 #4


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    Ehrenfest theorem can be derived even without using the Heisenberg picture, but if that picture is used then the derivation is trivial. Is it an answer to your question?
  6. Feb 6, 2009 #5
    yes it is
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