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arXiv · 1611.07595

A note on entanglement entropy and regularization in holographic interface theories

Michael Gutperle·Andrea Trivella
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Abstract

We discuss the computation of holographic entanglement entropy for interface conformal field theories. The fact that globally well defined Fefferman-Graham coordinates are difficult to construct makes the regularization of the holographic theory challenging. We introduce a simple new cut-off procedure, which we call "double cut-off" regularization. We test the new cut-off procedure by comparing the results for holographic entanglement entropies using other cut-off procedures and find agreement. We also study three dimensional conformal field theories with a two dimensional interface. In that case the dual bulk geometry is constructed using warped geometry with an $AdS_3$ factor. We define an effective central charge to the interface through the Brown-Henneaux formula for the $AdS_3$ factor. We investigate two concrete examples, showing that the same effective central charge appears in the computation of entanglement entropy and governs the conformal anomaly.

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Michael Gutperle, Andrea Trivella. 2016-11-23. A note on entanglement entropy and regularization in holographic interface theories. https://doi.org/10.1103/physrevd.95.066009

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