The Golden Ticket: P, NP and the Search for the Impossible

This awkward but eager work introduces readers to one of the most complicated problems in mathematics. P-type problems have a single solution and can be solved easily by computer, whereas NP, or “nondeterministic polynomial” problems, involve finding the relative “best” of numerous possible answers. NP problems include map-coloring puzzles, traveling-salesman puzzles (which seek to find the best combinations of routes between locations), and clique problems, like finding the largest group of people on Facebook who are all friends of each other. Fortnow’s “Golden Ticket” would be proof that P=NP, the discovery of efficient ways to solve NP-type problems. Whoever solves this decidedly nontrivial problem—one of the Clay Institute for Mathematics’ six unsolved “Millennium Problems”—will receive a $1 million prize. In addition to exploring the actual quandary, Fortnow, chair of the Georgia Institute of Technology’s school of computer science, lays out a quick modern history of mathematical problem solving, and enthuses over the possibilities of a “beautiful world” where P=NP: the ability to quickly sequence DNA, cure cancer and AIDs, and predict the weather. Despite moments of notational confusion—what exactly do “P H NP,” “P W NP,” and “P M NP” mean?—Fortnow effectively initiates readers into the seductive mystery and importance of P and NP problems. 41 halftones, 41 line illus. (Apr.)