Quantum mechanics and expectation values.

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SUMMARY

The discussion focuses on the calculation of expectation values in quantum mechanics, specifically the expression =∫Ψ*xΨ. It establishes that if the wave function Ψ is odd, then the product Ψ*Ψ results in an even function, leading to an expectation value of =0. Conversely, if Ψ is neither odd nor even, such as a Gaussian centered at x = x0, the expectation value can yield a non-zero result, specifically =x0.

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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?
 
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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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