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arXiv · 0801.1811

Information is Not Lost in the Evaporation of 2-dimensional Black Holes

Abhay Ashtekar·Victor Taveras·Madhavan Varadarajan
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Abstract

We analyze Hawking evaporation of the Callen-Giddings-Harvey-Strominger (CGHS) black holes from a quantum geometry perspective and show that information is not lost, primarily because the quantum space-time is sufficiently larger than the classical. Using suitable approximations to extract physics from quantum space-times we establish that: i)future null infinity of the quantum space-time is sufficiently long for the the past vacuum to evolve to a pure state in the future; ii) this state has a finite norm in the future Fock space; and iii) all the information comes out at future infinity; there are no remnants.

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Abhay Ashtekar, Victor Taveras, Madhavan Varadarajan. 2008-05-22. Information is Not Lost in the Evaporation of 2-dimensional Black Holes. https://doi.org/10.1103/physrevlett.100.211302

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