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arXiv · 1906.02207

The entanglement and relative entropy of a chiral fermion on the torus

Pascal Fries·Ignacio A. Reyes
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Abstract

We derive the entanglement entropy of chiral fermions on the circle at arbitrary temperature. The spin-sector contribution depends only on the total length of the entangling region, regardless of the configuration of the intervals. Thus three-partite information provides a global indicator for the spin boundary conditions. Together with the modular Hamiltonian, our results provide a systematic way of obtaining relative entropy on the torus.

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Pascal Fries, Ignacio A. Reyes. 2019-06-05. The entanglement and relative entropy of a chiral fermion on the torus. https://doi.org/10.1103/physrevd.100.105015

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