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arXiv · 1510.08872

Supersymmetric Renyi Entropy in $CFT_2$ and $AdS_3$

Amit Giveon·David Kutasov
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Abstract

We show that in any two dimensional conformal field theory with (2, 2) supersymmetry one can define a supersymmetric analog of the usual Renyi entropy of a spatial region A. It differs from the Renyi entropy by a universal function (which we compute) of the central charge, Renyi parameter n and the geometric parameters of A. In the limit $n \to1$ it coincides with the entanglement entropy. Thus, it contains the same information as the Renyi entropy but its computation only involves correlation functions of chiral and anti-chiral operators. We also show that this quantity appears naturally in string theory on $AdS_3$.

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Amit Giveon, David Kutasov. 2015-11-23. Supersymmetric Renyi Entropy in $CFT_2$ and $AdS_3$. https://doi.org/10.1007/jhep01(2016)042

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