BTW, there is a book for this class which is Griffiths QM (the same one used in 139a). We will be starting with material similar to Chapter 6 and then Ch 7, i.e., perturbation theory, H-atom fine structure, and variational calculations (that is, calculations of ground states and g.s. energies based on the variational principal). [Ground states are quite important. The idea of a finite kinetic energy ground state (as in the H atom, etc.) is basically a quantum concept with no classical analogue that I am aware of. ]
Regarding perturbation theory, note that there are two very different kinds of perturbation theory, one for non-degenerate states and one for when degenerate states are coupled to each other by a weak interaction term (a perturbation). The lifting of degeneracy and the 0-th order effect on the states is very important and somewhat distinct from the relatively continuous changes that occur in non-degenerate perturbation theory.
Make sure you have a clear idea what degeneracy means in this context.
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So, today in class were we talking about both types of perturbation theory, or just one of the two? I guess i should probably read 6.1 and 6.2, and that might clear things up.
just one type. "regular" (non-deg) perturbation theory. The other type is dramatically different. you'll see a very profound difference. In method, they are to a large degree, unrelated.
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