Some 40 years ago Bekenstein argued that black holes should have an enormous entropy. Shortly thereafter, Hawking showed that black holes evaporate in a way that violates quantum mechanics. The latter result has been a long standing problem, known as the black hole information paradox. Recent results in string theory has shown that the microstates corresponding to Bekenstein's entropy are 'fuzzballs' that do not have a regular horizon; the horizon of the hole arises as an emergent statistical concept. Further, the large entropy of these states leads to a violation of the semiclassical approximation at the horizon of a black hole; this alters Hawking's computation and provides a resolution of the information paradox.
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