Tom Hartman: The entropy of Hawking radiation

When black holes evaporate, they seem to violate quantum mechanics by creating too much entropy. This leads to the black hole information paradox, discovered by Hawking in 1976. I will describe recent progress on this problem that involves a new understanding of how to calculate the entropy of Hawking radiation. This relies on connections between classical geometry, quantum entanglement, and spacetime topology. The paradox is not yet overcome, however, because the same ingredients used to cure the entropy lead to new puzzles.