In 1949 Austrian-American logician Kurt Gödel gave a friend a strange birthday present: a rotating universe. Gödel is widely regarded as the world’s greatest logician. Albert Einstein, the greatest physicist, was his best friend. For years they walked home from the Princeton Institute for Advanced Study almost every day. The present—for Einstein’s 70th birthday—dealt with […]
An amazing birthday present: a universe that allows time travel and helps us understand our existence
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