I wanted to share my thoughts on this my favorite text on classical physics. It's become my favorite because it covers topics that many other books don't. At the beginning, the authors emphasized that they would be taking a geometric approach to understanding mathematical concepts, which really resonated with me. There are many topics I could discuss, but I've chosen my 2 favorites.
The first topic I enjoyed learning about was elasticity theory. I found the discussion on elastodynamics waves and their relation to earthquakes particularly fascinating. I was surprised to learn that earthquakes could be modeled using biharmonic waves. Additionally I really enjoyed the discussion on nonlinearities and Love numbers, as this had some connection to my research in years to come.
Here's a fun fact: My graduate program supervisor was a student of Roger D. Blandford, one of the co-authors of this book, so technically I am Roger's "Academic Grand-Disciple." After asking Roger to sign my book, we had a discussion about this particular chapter. The motivation for writing it was that K. S. Thorne was based at Caltech and Roger at Stanford, and they experienced a lot of earthquakes.
The other topic I thoroughly enjoyed was the chapter on nonlinear optics. I especially liked the discussion on the modes of the Fabry-Perot interferometer used in the LIGO detectors. The figures depicting the angular patterns of the modes were truly beautiful. Moreover, I liked the fact that they were hinting that we needed quantum optics to understand the noise generated in gravitational-wave interferometers.
Another fun fact: When I was a visiting student at Caltech, I had the pleasure of meeting Kip Thorne for the first time, and it was truly a pleasure to chat with him, especially about gravitational-wave physics, for which he is a master.
Overall, I highly recommend this book for any graduate student, or perhaps an advanced undergraduate who has had previous exposure to classical mechanics.