A problem on my quantum homework assignment this week has to do with the projection operator P = |a><a|(adsbygoogle = window.adsbygoogle || []).push({});

I've been asked to show that P^2=P, and then give the eigenvalues of P and then to characterize its eigenvectors. The first part is easy enough:

P = |a><a|

so P^2 = |a><a||a><a| = |a><a|a><a| = |a>(1)<a| = |a><a| = P

It's the second part I'm having trouble with:

P|psi> = p|psi> where little p is the eigenvalue.

and coming the eigenvectors. Can anyone offer me a little help?

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# Homework Help: Questions about the projection operator

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