Modified Quantum Harmonic Oscillator

Gabriel Maia
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This is more of a conceptual question and I have not had the knowledge to solve it.

We're given a modified quantum harmonic oscillator. Its hamiltonian is

H=\frac{P^{2}}{2m}+V(x)

where V(x)=\frac{1}{2}m\omega^{2}x^{2} for x\geq0 and V(x)=\infty otherwise.

I'm asked to justify in terms of the parity of the quantum problem eigenfunctions why only odd integers n are allowed for the eigenenergies of the problem E=(n+1/2)\hbar\omega

I have not a clue... well... actually my best guess was that the given potential impose the condition that the wavefunction is zero at x=0 and this is only the case for the odd ones. I'm confident about it but I could not find a problem like this anywhere to check my answer.


Thank you.
 
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That is exactly it well done.

attachment.php?attachmentid=62931&stc=1&d=1381812730.png
 

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Thank you for the validation :)
 
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