Finding Moonshine

After the fantastic The Music of the Primes, I started reading this book about groups and symmetry. Who knows.

Well, it is really very, very technical. I had a taste of group theory and the “Monster” thanks to 3Blue1Brown, but the book does a great job of explaining an extremely complicated concept in a relatively simple way. It is not for everyone.

I liked the first chapters, where he introduces the symmetry of simple bodies like the tetrahedron, cube, and hexagon, and how they are used in nature. Then it moves to the 17 symmetries in the Alhambra, and from there the path becomes complicated, tracing the history of mathematicians who spent decades and thousands of pages counting the different ways certain figures can be rotated and flipped while preserving their symmetry.

I have doubts about the practical aspects (aside from some developments in mathematics and symmetry). It really seems like a way to make things incredibly complicated, but anyway. Thanks to Marcus for making a subject that would otherwise be completely obscure interesting, and I appreciated both the anecdotes about many of these mathematicians (from Galois to Conway) and how the author added pieces of his own story and how he is working on his theory that blends group theory with other areas.

I understood maybe 30% of this book, I might reread.