To solve one of the great mathematical problems of his day, Alan Turing proposed an imaginary computer. Then, attempting to break a Nazi code during World War II, he successfully designed and built one, thus ensuring the Allied victory. Turing...
Why do compass needles point north―but not quite north? What guides the migration of birds, whales, and fish across the world’s oceans? How is Earth able to sustain life under an onslaught of solar wind and cosmic radiation? For centuries, the...