Expectation values for a harmonic oscillator

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SUMMARY

The discussion focuses on calculating expectation values for a particle in the first state of a harmonic oscillator, specifically , ,

, and . The wave function is given as \(\psi(x) = A\alpha^{1/2} x e^{-\alpha x^2/2}\). The expectation values are computed using the integral formula = \(\int \psi^* Q \psi \, dx\), where Q represents the relevant operator. The operators for and are confirmed as multiplication by \(x^2\) and \(-\hbar^2 \frac{\partial^2}{\partial x^2}\), respectively.

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KaiserBrandon
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Homework Statement


I need to find <x>, <x2>, <p>, and <p2> for a particle in the first state of a harmonic oscillator.


Homework Equations


The harmonic oscillator in the first state is described by \psi(x)=A\alpha1/2*x*e-\alpha*x2/2. I'm using the definition <Q>=(\int\psi1*Q*\psi)dx where \psi1 is the complex conjugate of \psi, and Q is the specific operator.


The Attempt at a Solution


I solved for <x>, and found it was zero. <p> I'll solve for in a similar fashion. However, for <x2> and <p2>, I am unsure of what operators I use. For the <x> operator, it is simply x, so for <x2>, would I use x2 as an operator?
(note that I the only superscripts here are the ones above e, I don't know why latex is putting all of my symbols so high
 
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KaiserBrandon said:
For the <x> operator, it is simply x, so for <x2>, would I use x2 as an operator?

Yes, that's what you should use.
 
(Put the whole equation in the tex barackets instead of individual symbols)

The operator for <x²> is simply multiplication by x², so <x²> = ∫ψ*(x)x²ψ(x)dx, and <p²> is

-\int \psi^{*}(x) \hbar^2\frac{\partial^2}{\partial x^2}\psi(x) dx
 
ok, thank you so much guys. It's a good thing I have physics forum to at least make my new ventures into the realm of quantum mechanics a bit easier :)
 

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