This book has nothing to do with physics, but its title will make you look super smart if you’re reading it on a train or plane. String Theory is a collection of five of Wallace’s best essays on tennis, a sport I gave up in my Microsoft days and am once again pursuing with a passion. You don’t have to play or even watch tennis to love this book. The late author wielded a pen as skillfully as Roger Federer wields a tennis racket. Here, as in his other brilliant works, Wallace found mind-blowing ways of bending language like a metal spoon.