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arXiv · 2412.03840

Bell-CHSH inequality and unitary transformations in Quantum Field Theory

D. O. R. Azevedo·F. M. Guedes·M. S. Guimaraes·I. Roditi·S. P. Sorella·A. F. Vieira
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Abstract

Unitary transformations are employed to enhance the violations of the Bell-CHSH inequality in relativistic Quantum Field Theory. The case of the scalar field in $1+1$ Minkowski space-time is scrutinized by relying on the Tomita-Takesaki modular theory. The example of the bounded Hermitian operator $sign(\varphi(f))$, where $\varphi(f)$ stands for the smeared scalar field, is worked out. It is shown that unitary deformations enable for violations of the Bell-CHSH inequality. The setup is generalized to the Proca vector field by means of its equivalence with the scalar theory.

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D. O. R. Azevedo, F. M. Guedes, M. S. Guimaraes, I. Roditi, S. P. Sorella, A. F. Vieira. 2024-12-05. Bell-CHSH inequality and unitary transformations in Quantum Field Theory. https://doi.org/10.1140/epjc%2Fs10052-026-15445-1

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