Andrea Puhm (Gif-sur-Yvette):

Unitarity, information, black holes and fuzzballs

Abstract:

The information paradox has been a long-standing puzzle in the understanding of black holes. Recently it has been shown that small corrections to the leading-order Hawking process do not invalidate Hawkings conclusion, instead unless there is a large departure from the traditional black hole horizon information will be lost. The recent firewall proposal further supports this result. In a more thorough analysis of unitary evaporation using qubit models we argue that the notion of the traditional black hole horizon has to be given up completely in order to save unitarity. This supports the fuzzball conjecture according to which the true microstates of quantum gravity are singularity-free and horizonless solutions which have non-trivial structure at the location where the horizon of the black hole would be and thus evaporate unitarily: there is no information paradox and the black hole is a coarse-grained description of fuzzballs. We elaborate on the importance of energy scale separation regarding the information and the infall question.

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