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arXiv · 2312.06918

Using Weyl operators to study Mermin's inequalities in Quantum Field Theory

Philipe De Fabritiis·Fillipe M. Guedes·Marcelo S. Guimaraes·Itzhak Roditi·Silvio P. Sorella
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Abstract

Mermin's inequalities are investigated in a Quantum Field Theory framework by using von Neumann algebras built with Weyl operators. We devise a general construction based on the Tomita-Takesaki modular theory and use it to compute the vacuum expectation value of the Mermin operator, analyzing the parameter space and explicitly exhibiting a violation of Mermin's inequalities. Therefore, relying on the power of modular operators, we are able to demonstrate that Mermin's inequalities are violated when examined within the vacuum state of a scalar field theory.

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Philipe De Fabritiis, Fillipe M. Guedes, Marcelo S. Guimaraes, Itzhak Roditi, Silvio P. Sorella. 2023-12-12. Using Weyl operators to study Mermin's inequalities in Quantum Field Theory. https://doi.org/10.1103/physrevd.109.045020

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