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Quantum mechanics and expectation values.

  1. Sep 17, 2011 #1
    I have a question about expectation values in quantum mechanics.

    When calculating <x>=[itex]\int\Psi*x\Psi[/itex] does x always make this functions odd? If [itex]\Psi[/itex] is odd then [itex]\Psi*[/itex] I would assume is odd as well and then <x> would be odd*odd*odd, if [itex]\Psi[/itex] is even then I again assume it would be even*odd*even. Does an odd function make the whole function odd regardless?
  2. jcsd
  3. Sep 18, 2011 #2


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    In the two cases you mentioned, Ψ odd or Ψ even, like you say Ψ*Ψ will be even and you'll get <x>=0. However what if Ψ is neither odd nor even? If, for example, Ψ is a Gaussian centered at x = x0 then you'll get <x> = x0 ≠ 0.
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