This is a great book, with many strengths and a few weaknesses. As the author readily admits on p. 15: "This is not a comprehensive or scholarly dissertation, but rather it is intended as recreational reading for students of science and mathematics and interested laypeople." The "recreational-reading" objective explains the blending of some lightweight material with deep results. The book consists of self-contained articles, presented in chronological order, each consisting of one page of text and one page of graphics. In a majority of instances, however, the graphics are decorative, providing little in way of illustrating the concepts or making them easier to understand.
Having discussed the weaknesses, let me shift my focus to the book's strengths. Pickover, the prolific author of 40+ books, has a gift for describing mathematical concepts in accessible form. On p. 14, the author whets the reader's appetite by promising answers to a number of intriguing questions:
- Why was the first female mathematician murdered?
- Who was the "Number Pope"?
- Who was the earliest named individual in the history of mathematics?
The very first idea ("Ant Odometer," p. 15), dating back 150 million years, concerns the way ants have evolved to be able to return home along a straight line, after traveling along a winding path in search of food. They accomplish this feat using their sense of direction and their ability to count steps. If an ant's legs are artificially shortened or lengthened before its return trip, it either does not reach its nest or overshoots it.
The final entry in the book, "Mathematical Universe Hypothesis" (p. 516), describes the work of MIT Physics Professor Max Tegmark, who hypothesized in 2007 that our universe isn't just described by mathematics—it is mathematics! "[W]e don't invent mathematical structures—we discover them, and invent only the notation for describing them."
From among the other 248 entries, let me describe just one: "Andrica's Conjecture" (p. 482). If p(n) is the nth prime number and g(n) = p(n+1) – p(n) is the gap between p(n) and the next prime p(n+1), then g(n) < 2 sqrt(p(n)) + 1. Put another way, sqrt(p(n+1)) – sqrt(p(n)) < 1. This relationship remains an unproven conjecture, but it is believed to be true based on empirical evidence.
I was particularly intrigued by three entries describing ideas from Persian mathematicians/philosophers. On p. 84, we read about "Al-Khwarizmi's Algebra" (830 CE), the first book on the systematic solution of linear and quadratic equations. Then, on p. 94, "Omar Khayyam's Treatise" (1070 CE), having to do with solving third-degree and some higher-order equations, is discussed, as well as his writings on properties of non-Euclidean geometries, an area that did not flourish until the 1800s. Ghiyath al-Din Jamshid al-Kashi's "Law of Cosine" (ca. 1427 CE), which relates the side lengths of a triangle and the cosine of the angle opposite to the side of length c by the identity c^2 = a^2 + b^2 – 2ab cos(C). The latter identity includes the Pythagorean theorem c^2 = a^2 + b^2 as a special case corresponding to C = 90 degrees.
Pickover's fascinating book ends with 8 pages of notes, providing details and references for the entries, a 2-page index, and one page of photo credits.