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arXiv · 1510.00021

Universal Entanglement and Boundary Geometry in Conformal Field Theory

Christopher P. Herzog·Kuo-Wei Huang·Kristan Jensen
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Abstract

Employing a conformal map to hyperbolic space cross a circle, we compute the universal contribution to the vacuum entanglement entropy (EE) across a sphere in even-dimensional conformal field theory. Previous attempts to derive the EE in this way were hindered by a lack of knowledge of the appropriate boundary terms in the trace anomaly. In this paper we show that the universal part of the EE can be treated as a purely boundary effect. As a byproduct of our computation, we derive an explicit form for the A-type anomaly contribution to the Wess-Zumino term for the trace anomaly, now including boundary terms. In d=4 and 6, these boundary terms generalize earlier bulk actions derived in the literature.

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Christopher P. Herzog, Kuo-Wei Huang, Kristan Jensen. 2015-10-16. Universal Entanglement and Boundary Geometry in Conformal Field Theory. https://doi.org/10.1007/jhep01(2016)162

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