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arXiv · 0710.2956

Near Extremal Black Hole Entropy as Entanglement Entropy via AdS2/CFT1

Tatsuo Azeyanagi·Tatsuma Nishioka·Tadashi Takayanagi
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Abstract

We point out that the entropy of (near) extremal black holes can be interpreted as the entanglement entropy of dual conformal quantum mechanics via AdS2/CFT1. As an explicit example, we study near extremal BTZ black holes and derive this claim from AdS3/CFT2. We also analytically compute the entanglement entropy in the two dimensional CFT of a free Dirac fermion compactified on a circle at finite temperature. From this result, we clarify the relation between the thermal entropy and entanglement entropy, which is essential for the entanglement interpretation of black hole entropy.

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Tatsuo Azeyanagi, Tatsuma Nishioka, Tadashi Takayanagi. 2007-12-30. Near Extremal Black Hole Entropy as Entanglement Entropy via AdS2/CFT1. https://doi.org/10.1103/physrevd.77.064005

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