-----------------------------------------------------------------------------
Problem 11
Solve problems 4.5 and 4.6 in Harrison
Problem 12
Consider Cooper pairs with non-zero total momentum. Show that their binding energy is smaller than that of pairs with zero total momentum if the interaction is attractive in a shell around the Fermi surface.
Problem 13
Calculate the fluctuations in particle number in the BCS wave function
Problem 14
Show that the BCS equations follow from applying the variational principle to the BCS wave function
-----------------------------------------------------------------------------