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arXiv · 1905.05210

Modular Hamiltonian of a chiral fermion on the torus

David Blanco·Guillem Pérez-Nadal
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Abstract

We consider a chiral fermion at non-zero temperature on a circle (i.e., on a torus in the Euclidean formalism) and compute the modular Hamiltonian corresponding to a subregion of the circle. We do this by a very simple procedure based on the method of images, which is presumably generalizable to other situations. Our result is non-local even for a single interval, and even for Neveu-Schwarz boundary conditions. To the best of our knowledge, there are no previous examples of a modular Hamiltonian with this behavior.

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David Blanco, Guillem Pérez-Nadal. 2019-05-13. Modular Hamiltonian of a chiral fermion on the torus. https://doi.org/10.1103/physrevd.100.025003

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