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arXiv · hep-th/9904143

Vacuum States for AdS_2 Black Holes

Marcus Spradlin·Andrew Strominger
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Abstract

An AdS_2 black hole spacetime is an AdS_2 spacetime together with a preferred choice of time. The Boulware, Hartle-Hawking and SL(2,R) invariant vacua are constructed, together with their Green functions and stress tensors, for both massive and massless scalars in an AdS_2 black hole. The classical Bekenstein-Hawking entropy is found to be independent of the temperature, but at one loop a non-zero entanglement entropy arises. This represents a logarithmic violation of finite-temperature decoupling for AdS_2 black holes which arise in the near-horizon limit of an asymptotically flat black hole. Correlation functions of the SL(2,R) invariant boundary quantum mechanics are computed as functions of the choice of AdS_2 vacuum.

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Marcus Spradlin, Andrew Strominger. 1999-10-26. Vacuum States for AdS_2 Black Holes. https://doi.org/10.1088/1126-6708%2F1999%2F11%2F021

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