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arXiv · 2310.03493

The Fermionic Entanglement Entropy and Area Law for the Relativistic Dirac Vacuum State

Felix Finster·Magdalena Lottner·Alexander V. Sobolev
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Abstract

We consider the fermionic entanglement entropy for the free Dirac field in a bounded spatial region of Minkowski spacetime. In order to make the system ultraviolet finite, a regularization is introduced. An area law is proven in the limiting cases where the volume tends to infinity and/or the regularization length tends to zero. The technical core of the paper is to generalize a theorem of Harold Widom to pseudo-differential operators whose principal symbols develop a specific discontinuity at a single point.

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Felix Finster, Magdalena Lottner, Alexander V. Sobolev. 2023-10-05. The Fermionic Entanglement Entropy and Area Law for the Relativistic Dirac Vacuum State. https://doi.org/10.4310/atmp.241031011130

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