What If the Universe Had No Beginning? Part 2: No Boundary, No Problem

Stephen Hawking, whose no-boundary proposal argued that asking what came before the big bang is like asking what is south of the south pole. (Public domain, NASA StarChild)

Hawking faced a question with no answer hiding behind it. The best boundary condition for the universe, he decided, was that there was no boundary at all. To make that statement into physics, he had to do something deeply strange to time.

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