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einai
Mar26-04, 09:07 PM
Hi, I came across a problem which seems to be pretty simple, but I'm stuck :confused: .

Given a Hamiltonian:
H=\frac{\vec{p}^2}{2m}+V(\vec{x})

If |E> is a bound state of the Hamiltonian with energy eigenvalue E, show that: <E| \vec{p} |E>=0

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So I've been trying something like this:

\frac{1}{2m}<E|\vec{p} \cdot \vec{p}|E> + <E|V(\vec{x})|E> = E<E|E> = E

but I have no idea how to proceed from here. I don't think I'm on the right track actually.

Thanks in advance!

Doc Al
Mar27-04, 07:46 PM
FYI: This question has been answered in the quantum physics forum.