Recent content by mathingenue

I understand that we can choose any linear combination of these states as our starting point, and that we are trying to diagonalize the perturbation in the degenerate subspace, but why exactly are we trying to diagonalize the perturbation in the degenerate subspace?

I do hope my doubts are clearer now.

I think the part that has been giving me the most trouble is the end of page 259 of the second edition, when Griffiths talks about the "good states". He says that if we could guess the good states then we could go ahead and use nondegenerate perturbation theory, and he introduces a theorem that...

Anyone else would like to help?

Yes A. Neumaier, unfortunately I'm not well versed in representation theory...

Yes, but I can't seem to move forward in understanding his answer.

Hello gentzen, I'm afraid the equations aren't the problem, the text is. I merely pointed to them as a reference of where in vanhees71's text I got lost.

Thanks for taking the time to write a long answer vanhees71, and thank you for the Sakurai reference, but I'm afraid your answer is simply too complicated for me. I did try going through it in detail, but basically you lost me after the equations $$\langle E',\alpha' |E,\alpha...

Hello folks, I am currently studying from Griffiths' Introduction to Quantum Mechanics and I've got a doubt about good quantum numbers that the text has been unable to solve. As I understand it, good quantum numbers are the eigenvalues of the eigenvectors of an operator O that remain...