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Ehrenfest's Theorem

  1. May 30, 2010 #1
    If I had a hamiltonian of the form iA(p + c), where A is a constant matrix, p the momentum operator and c an ordinary constant how do I find the time rate of change of the expectation momentum value?
    I've tried using Ehrenfest's theorem but I don't understand whether in [p,H], I should treat p as an operator or as an ordinary number? Could someone please make this clearer to me? Thanks.
  2. jcsd
  3. May 31, 2010 #2


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    P is an operator in the commutator. Its commutator with itself is the zero operator.
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