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arXiv · 0907.1559

Holographic entanglement entropy of the BTZ black hole

M. Cadoni·M. Melis
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Abstract

We investigate quantum entanglement of gravitational configurations in 3D AdS gravity using the AdS/CFT correspondence. We derive explicit formulas for the holographic entanglement entropy (EE) of the BTZ black hole, conical singularities and regularized AdS$_{3}$. The leading term in the large temperature expansion of the holographic EE of the BTZ black hole reproduces exactly its Bekenstein-Hawking entropy S_BH, whereas the subleading term behaves as ln S_BH. We also show that the leading term of the holographic EE for the BTZ black hole can be obtained from the large temperature expansion of the partition function of a broad class of 2D CFTs on the torus. This result indicates that black hole EE is not a fundamental feature of the underlying theory of quantum gravity but emerges when the semiclassical notion of spacetime geometry is used to describe the black hole.

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M. Cadoni, M. Melis. 2009-07-09. Holographic entanglement entropy of the BTZ black hole. https://doi.org/10.1007/s10701-010-9430-6

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