Modification to the simple harmonic oscillator

jamesonWHIS
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Homework Statement
The simple harmonic oscillator Hamiltonian is altered such that the p' = p + 2mcx. How does this affect the condition necessary for the matrix elements <m|x|n> and <m, x^2| n> to be nonzero, given |n> is an eigenstate of the original harmonic oscillator.
Relevant Equations
x = Sqrt(h/2mw)(a + adagger)
I was assuming there could be something via perturbation theory? I am unsure.
 
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At first glance, I don't think that perturbation theory is necessary. The ##\ket{n}## form a complete basis, even for the modified Hamiltonian.

However, I do not understand the question. "Given ##\ket{n}## is an eigenstate of the original harmonic oscillator," then ##\braket{m|\hat{x}|n}## and ##\braket{m|\hat{x}^2|n}## are unchanged, whatever the Hamiltonian is.
 
DrClaude said:
At first glance, I don't think that perturbation theory is necessary. The ##\ket{n}## form a complete basis, even for the modified Hamiltonian.
I would like to question this statement. How do you know such modification doesn't change the size of the Hilbert's space?
 
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