arXiv:1309.2189 · Journal of Statistical Mechanics Theory and Experiment

On Rényi entropies of disjoint intervals in conformal field theory

Andrea Coser, Luca Tagliacozzo, Erik Tonni C

Published Jan 20, 2014• 96 citations

Abstract

We study the Rényi entropies of N disjoint intervals in the conformal field theories given by the free compactified boson and the Ising model. They are computed as the 2N point function of twist fields, by employing the partition function of the model on a particular class of Riemann surfaces. The results are written in terms of Riemann theta functions. The prediction for the free boson in the decompactification regime is checked against exact results for the harmonic chain. For the Ising model, matrix product states computations agree with the conformal field theory result once the finite size corrections have been taken into account.

DOI: 10.1088/1742-5468/2014/01/p01008

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