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Creation and annihilation operator in quantum mechanics?

  1. Oct 24, 2009 #1
    What is exactly the creation and annihilation operator in quantum mechanics?
    What its physical significance?
  2. jcsd
  3. Oct 24, 2009 #2
    Re: operator

    Take a harmonic oscillator Hamiltonian like H(p,x) = p2 + x2. Then make the variable changes: a = p + ix and a+ = p - ix. Now your Hamiltonian becomes H(a,a+) = a+a or so. So a and a+ are just some other variables.
  4. Oct 24, 2009 #3


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    Re: operator

    In QM this can be used, for instance for the QM harmonic oscillator, to construct eigenfunctions of the Hamiltonian by acting with these creation operators on the vacuum |0>.

    In quantum field theory you normally promote the field itself to be an operator in order to treat space and time as labels of these fields; after all, in special relativity they are on equal foot so you shouldn't treat one as an operator (x) and the other as a label (t) parametrizing motion.
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