Thermal corrections to Rényi entropies for free fermions

  • Christopher P. Herzog
  • Michael Spillane
Open Access
Regular Article - Theoretical Physics


We calculate thermal corrections to Rényi entropies for free massless fermions on a sphere. More specifically, we take a free fermion on \( \mathbb{R}\times {\mathbb{S}}^{{{}^d}^{-1}} \) and calculate the leading thermal correction to the Rényi entropies for a cap like region with opening angle 2θ. By expanding the density matrix in a Boltzmann sum, the problem of finding the Rényi entropies can be mapped to the problem of calculating a two point function on an n sheeted cover of the sphere. We follow previous work for conformal field theories to map the problem on the sphere to a conical region in Euclidean space. By using the method of images, we calculate the two point function and recover the Rényi entropies.


Conformal and W Symmetry Field Theories in Higher Dimensions Thermal Field Theory 


Open Access

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Copyright information

© The Author(s) 2016

Authors and Affiliations

  1. 1.C.N. Yang Institute for Theoretical Physics, Department of Physics and AstronomyStony Brook UniversityStony BrookU.S.A.

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