Better late than never: Information retrieval from black holes

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We show that, in order to preserve the equivalence principle until late times in unitarily evaporating black holes, the thermodynamic entropy of a black hole must be primarily entropy of entanglement across the event horizon. For such black holes, we show that the information entering a black hole becomes encoded in correlations within a tripartite quantum state, the quantum analogue of a one-time pad, and is only decoded into the outgoing radiation very late in the evaporation. This behavior generically describes the unitary evaporation of highly entangled black holes and requires no specially designed evolution. Our work suggests the existence of a matter-field sum rule for any fundamental theory.
Original languageEnglish
Article number101301
Number of pages5
JournalPhysical Review Letters
Issue number10
Early online date5 Mar 2013
Publication statusPublished - 8 Mar 2013

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© 2013 the authors. Published by the American Physical Society as Open Access under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

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