What’s the Use: How Mathematics Shapes Everyday Life

“It would be easy to conclude that mathematics has become outdated,” but modern life would “fall apart” without it, argues mathematician Stewart (Does God Play Dice) in this straightforward survey. With 13 examples that cover movie animation, internet traffic, medicine, photography, and navigation apps, Stewart explains the ways math makes modern life possible. He ties the math of airline routing to the classic “traveling salesman problem” (a way to make a route the most efficient), and explains that GPS users employ Einstein’s theory of relativity each time they plan a trip. Graph theory, meanwhile, is used to match organ donors with recipients, and computer-generated imagery is built on 175-year-old math. He also describes how various mathematical concepts were developed, which, taken together, provide a thumbnail history of mathematics. Stewart goes incredibly deep into the difficult math that informs his examples, a choice that will undoubtedly stretch even the most mathematically inclined readers (pseudorandom number generators, he writes, are “generally based on abstract algebra, such as polynomials over finite fields, or number theory, such as integers to some modulus”). But those who stay the course will find that Stewart succeeds in conveying his wonder at the power math has to shape the world. (Aug.)