Following on the success of his books Math Hysteria and How to Cut a Cake, Ian Stewart is back with more stories and puzzles that are as quirky as they are fascinating, and each from the cutting edge of the world of mathematics. From the math of mazes, to cones with a twist, and the amazing sphericon—and how to make one—Cows in the Maze takes readers on an exhilarating tour of the world of mathematics. We find out about the mathematics of time travel, explore the shape of teardrops (which are not tear-drop shaped, but something much, much more strange), dance with dodecahedra, and play the game of Hex, among many more strange and delightful mathematical diversions. In the title essay, Stewart introduces readers to Robert Abbott's mind-bending "Where Are the Cows?" maze, which changes every time you pass through it, and is said to be the most difficult maze ever invented. In addition, he shows how a 90-year old woman and a computer scientist cracked a long-standing question about counting magic squares, describes the mathematical patterns in animal movement (walk, trot, gallop), looks at a fusion of art, mathematics, and the physics of sand piles, and reveals how mathematicians can—and do—prove a negative. Populated by amazing creatures, strange characters, and astonishing mathematics explained in an accessible and fun way, and illustrated with quirky cartoons by artist Spike Gerrell, Cows in the Maze will delight everyone who loves mathematics, puzzles and mathematical conundrums.