Fourth lecture advanced quantum mechanics
was difficult and somewhat technical. Hopefully, it was not boring since I’ve been trying all side stories to keep the audience attending. Besides the material, the microscopic theory of superconductivity being the main topic of it, traditionally interests students.
There are still many students, more than in years past. They also react differently than in the past. For instance, I used to encounter resistance when coming to work whithin a single Nambu cell, I was requested and had to write the wavefunction as a 2-vector and act with 2×2 matrix thereupon. Today I did not get such request, the students seem to follow. However, just by inertia, I wrote 2-vectors and 2×2 matrix at the blackboard… I’ve thrown a question about contact interaction in completely polarized electron gas where it cancels because electrons cannot come close to each other. Actually, in the past the answer to this question used to come quickly, immediately after the hint that they do not come close to each other. Today there was a significant delay… Why? Luckily, the answer has emerged after a while. A similar question — where did the factor 2 go? — has been answered a way too quickly. So I suspect telepatic abilities in a part of the audience.
As to my telepatic skills, I have to brush them. Close to the end of the lecture, I began to hear very distracting noises from the adjacent room. Bet most students did not hear that and wondered about the reason of my distraction. I tried to send a telepatic message to the noise source. No avail, I had to break the lecture and appear in person. There were four young gentlemen enjoying table soccer match. While apparently surprised by my request to do it queiter, they were kind enough to accomodate it.
I still have to decide what to do with superfluidity. It looks like I will have to combine with classical description of electromagnetic field. In this case, that’s going to be a mjour pedagogical innovation: do not miss it!
