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arXiv · 2610.20398

Relative entropy in quantum field theory: the case of squeezed fermions

Markus B. Fröb
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Abstract

We review the role of relative entropy in quantum field theories, where the local von Neumann algebras are generically of type III. Consequently, only few exact results are known, and even bounds are difficult to obtain. As a new result, we prove that the relative entropy between a locally squeezed state and the Minkowski vacuum is finite for free fermions.

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Markus B. Fröb. 2026-10-14. Relative entropy in quantum field theory: the case of squeezed fermions. https://arxiv.org/abs/2610.20398

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