A Zee's books are fantastic

Prof. J. Pochinski wrote in the preface of his famous string theory textbook that "one of the greatest pleasures was finding a text that made a difficult subject accessible". To me, Prof. A. Zee's new textbook "Group Theory in a Nutshell for Physicists" is such a great text that explains a lot of concepts in group theory clearly and patiently.

On one night in the last week, I opened this book for some random reading to save myself temporarily out of the recent boring daily work. It turns out I sit there for one hour and read 70 pages (page 185-255) in one go, with no awareness of the elapsed time. I took a undergraduate course of group theory before, and thus are familiar with the technical parts like $J_{\pm}, J_{z}$ or $|j, m\rangle$. But still, this is the first book I've read that explains the concepts of (irreducible) tensor representations of SO(N) and SU(N) clearly. For example, the author devoted a lot of space to convince his readers that why symmetric patterns on the tensor indices matter, or why both upper and lower indexes are needed in SU(N) but not in SO(N). Such explanations in plain language besides the mathematical formula are extremely valuable for self study. I wish I had this book when I was in graduate school so that I won't suffer a lot in the self study. BTW, Prof. J. Polchinski also provided a great text on SO(N) spinors in Appendix B. 1 of his string theory textbook.

Note that most of the one-semester group theory courses only covers the topics up to SO(3) that are closely related to ordinary quantum mechanics. There is usually no coverage on topics on the representations of high-dimensional SO(N) or SU(N), which happens to be one of the prerequisites in modern high energy physics. When I was a graduate student, I could not find a friendly textbook on such topics. At that time, the only available textbook in Chinese is very very terrible. There are tons of complicated notations such that one can not pick up some chapter in between without reading the book from the beginning. Life became much easier when I read Prof. H. Georgi's book "Lie Algebra in Particle Physics" instead. This book is great but is still a bit unfriendly for self study, since it is more like a collection of lecture notes and lacks enough explanations on concepts in plain language as Prof. A. Zee did. For example, I could easily understand the Wigner-Eckwart theorem from a two-page description (page 224-225) in Prof. A. Zee's book, but spent much more time on the same topic when reading Prof. H. Georgi's book.

It's worth to mention that Prof. A. Zee is a great writer on both textbooks and popular science books on modern physics. For example, he wrote another textbook "Quantum Field Theory in a Nutshell". My Ph.D. thesis advisor read this book and even did the exercises to refresh QFT after I joined his group. To me, I believe Prof. A. Zee's book "Fearful Symmetry" is the top one  popular science book on modern theoretical physics. I read an unauthorized Chinese version of this book in the summer before entering the high school, and even today I still remembered the satisfaction when understanding the message in the book that special relativity is nothing but on invariants between different frames. Given the big impact of this popular science book on my life along with others in 第一推动丛书 (My interest changed from history to physics afterwards and I majored in physics in the university), I bought the English version of this book as a gift to one of my best friends, Joking. Hope he can enjoy the beauty of modern theoretical physics as well.

BTW, one commonly unknown fact on 第一推动丛书 is that this series of popular science books is initialized by the Prof. Lizhi Fang, as mentioned in his wife's memorial article.

  

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