I just finished preparing my undergraduate lecture on ideal Fermi gases at zero temperature. Here are my slides.
(Note. The derivations are not included, as I sketch them by hand on a document viewer.) (Aside. Personally, I would prefer to do derivations on the whiteboard, but this is viewed unfavourably as the video recording of the lecture will not capture that.)
A few things I find amazing about the lecture content.
Degeneracy pressure is a macroscopic quantum effect, since it vanishes in the limit Planck's constant goes to zero.
Degeneracy pressure is relevant to astrophysics. I enjoyed learning more about how it prevents the collapse of white dwarfs and neutron stars. For the first time (to my memory) I derived the Chandrasekhar limit for white dwarfs. I also enjoyed seeing how this limit is essentially the same physics as the Tolman-Oppenheimer-Volkoff limit for neutron stars.
An earlier post discussed some things I find amazing about Chandrasekhar's expression for the upper.
A few historical notes I found interesting.
It is the 100th anniversary of Fermi-Dirac statistics and the distribution function. It is impressive how Ralph Fowler immediately saw how the degeneracy pressure could explain the stability of white dwarfs. He was the PhD supervisor of Dirac, Chandrasekhar, and Mott. He was also the first to define the zeroth law of thermodynamics.
Chandrasekhar's limit was not accepted for a long time because of the opposition of Arthur Eddington. In hindsight, some consider this was a setback for astrophysics, particularly interest in the possibility of black holes, for decades. This opposition to the profound new ideas of a young PhD student by a legendary senior figure reminded me of Bardeen's opposition to Josephson. However, in that case, within a few years, experiments showed that the establishment figure was wrong.
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