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arXiv · 1204.1982

Time evolution of entanglement entropy from a pulse

Matthew M. Roberts
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Abstract

We calculate the time evolution of the entanglement entropy in a 1+1 CFT with a holographic dual when there is a localized left-moving packet of energy density. We find the gravity result agrees with a field theory result derived from the transformation properties of Rényi entropy. We are able to reproduce behavior which qualitatively agrees with CFT results of entanglement entropy of a system subjected to a local quench. In doing so we construct a finite diffeomorphism which tales three-dimensional anti-de Sitter space in the Poincaré patch to a general solution, generalizing the diffeomorphism that takes the Poincaré patch a BTZ black hole. We briefly discuss the calculation of correlation functions in these backgrounds and give results at large operator dimension.

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Matthew M. Roberts. 2012-04-09. Time evolution of entanglement entropy from a pulse. https://doi.org/10.1007/jhep12(2012)027

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