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arXiv · 2107.00039

Modular operator for null plane algebras in free fields

Vincenzo Morinelli·Yoh Tanimoto·Benedikt Wegener
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Abstract

We consider the algebras generated by observables in quantum field theory localized in regions in the null plane. For a scalar free field theory, we show that the one-particle structure can be decomposed into a continuous direct integral of lightlike fibres, and the modular operator decomposes accordingly. This implies that a certain form of QNEC is valid in free fields involving the causal completions of half-spaces on the null plane (null cuts). We also compute the relative entropy of null cut algebras with respect to the vacuum and some coherent states.

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Vincenzo Morinelli, Yoh Tanimoto, Benedikt Wegener. 2021-06-30. Modular operator for null plane algebras in free fields. https://doi.org/10.1007/s00220-022-04432-8

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