THE BIG BOOK OF PI

What is this essential number, and why can we “never know” it?

Pi is everywhere, and an obsession for some. This book is, per the title, “big” (everything we could want to know) but never overwhelmingly so. Lehmann and Aubin explain the math and the name, while engagingly connecting the numbers to the average reader. The book includes pi brain-twisters (including accessible, tricky pizza-cutting techniques), jokes, and an “e-Pi-logue,” along with calculations, a glossary, and a chyron of definitions wherever useful. Puns, eminent mathematicians’ quotations, and geeky fun facts are scattered here and there, one being that the distribution of stars in the sky reflects pi. Along the way, the authors manage to tie in a swath of topics, some seemingly unrelated, among them cognitive bias, irrational numbers, decimals, and Babylonian and Egyptian math; they also profile Chinese, Indian, Persian, and later mathematicians, including Madhava of Kerala, who made calculus a working tool. The style is chatty and hip. Demonstrating the ubiquity of number sequences, for instance, the authors assert that you can find in pi sequences your own birth date, but also “your boring uncle’s, your pet iguana’s, Srinivasa Ramanujan’s, Isaac Newton’s, Beyoncé’s…” Sildre’s teal, red, and blue graphic novel–style illustrations, clever and amusing, are also instructive. Ada Lovelace, Katherine Johnson, Emma Haruka Iwao, and Maryam Mirzakhani appear in cameos. Even math-phobes will find this pi tasty and nourishing.

An astonishing, delightful, and illuminating celebration of mathe-magics.