Why I love Ashcroft and Mermin

It is amazing but I never took an introductory Solid State Physics course, either as an undergraduate or as a graduate student! As an undergraduate at ANU, the course was an elective and so I avoided the course because my previous experience with the lecturer was he was incompetent. At Princeton I had to pass a "General exam" which covered solid state, nuclear, particle physics, and general relativity. I taught myself solid state physics by reading a library copy of Ziman's Principles of the Theory of Solids. I don't remember why I made this choice but I suspect it was partly that Solid State Physics by Ashcroft and Mermin seemed too big.

I bought a second hand copy of Ashcroft and Mermin when I was a postdoc, but only started to really read it later. I think the way it progresses is brilliant. It works from the Drude model for metals to the Sommerfeld model, highlighting their successes and failures. Only then does it introduce crystal structures, motivated by the goal of understanding the Bloch model. In contrast, Kittel and Marder begin with crystal structures.
I think the approach of Ashcroft and Mermin has incredible value because it shows how good science is done: looking at experimental data and then developing the simplest possible model to explain the data, and using data to eliminate competing models. This is a great example of the method of multiple alternative hypotheses.

I also think reading the first few chapters helped me to do some of my best research. It helped me appreciate the different signatures of a Fermi liquid with coherent quasi-particles compared to a "bad metal" with incoherent excitations. These ideas were key in writing a paper Transport properties of strongly correlated metals: a dynamical mean-field approach with Jaime Merino.