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arXiv · 1008.3439

Measuring Black Hole Formations by Entanglement Entropy via Coarse-Graining

Tadashi Takayanagi·Tomonori Ugajin
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Abstract

We argue that the entanglement entropy offers us a useful coarse-grained entropy in time-dependent AdS/CFT. We show that the total von-Neumann entropy remains vanishing even when a black hole is created in a gravity dual, being consistent with the fact that its corresponding CFT is described by a time-dependent pure state. We analytically calculate the time evolution of entanglement entropy for a free Dirac fermion on a circle following a quantum quench. This is interpreted as a toy holographic dual of black hole creations and annihilations. It is manifestly free from the black hole information problem.

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BibTeXRIS

Tadashi Takayanagi, Tomonori Ugajin. 2010-08-20. Measuring Black Hole Formations by Entanglement Entropy via Coarse-Graining. https://doi.org/10.1007/jhep11(2010)054

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