How two mathematicians solved a cryptography mystery

On October 30, 1942, a group of destroyer warships from the British Royal Navy hunted down a Nazi submarine near the Nile Delta. The warships pounded the submarine with underwater explosions until it floated to the surface, where it started filling with water and sinking. As its German crew scrambled to escape, three British heroes—Lieutenant Anthony Fasson, sailor Colin Grazier and 16-year-old canteen assistant Tommy Brown—did something that defied all instinct. They jumped from their ship onto the sinking vessel and climbed inside.They were after the sub’s most valuable cargo: not weapons, not prisoners, but books. The pages contained codes for tuning the Nazi “Enigma machine” that allowed the German forces to communicate in secret. Deep inside the flooding commanding officers’ quarters, the men seized the volumes before the water-soluble ink dissolved into the sea. Only the teenager made it out alive. Less than two months later English mathematician Alan Turing’s team of code breakers used the codes to decipher Nazi messages, an effort estimated to have shortened the war by two years, saving millions of lives.Cryptography is the math of communicating in secret, and it’s as high stakes as math gets. The submarine story and dozens more like it