1. Quantum II (PHYS 4410) Lecture 17 Dipole-dipole hyperfine structure HWK 6 is due Wednesday at 6PM.

3. 150 A) Non-degenerate perturbation theory because the ground state is non-degen. B) Degenerate perturbation theory because the ground state is degenerate. To do perturbation theory for the hydrogen ground state, we use Hint: How many quantum numbers do we have and how many combinations?

4. 150 A) 2-fold degenerate B) 3-fold degenerate C) 4-fold degenerate D) Something larger. Including the proton and the electron spins, the hydrogen ground state is:

5. 150 A) |n=1, l =0,m zP, m ze > are ‘good’ states B) |n=1, l =0,m zP, m ze > are not ‘good’ states C) It does not matter as the δ -function makes things zero anyway. When we calculate the first-order energy shift of the ground state due to the term:

7. 150 A) TRUE B) FALSE C) 42 D) Something larger. TRUE or FALSE: I have seen a system of two spin-1/2 particles that has a four-dimensional Hilbert Space