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arXiv · 2006.05537

Bell Non-Locality in Many Body Quantum Systems with Exponential Decay of Correlations

Carlos H. S. Vieira·Cristhiano Duarte·Raphael C. Drumond·Marcelo Terra Cunha
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Abstract

Using Bell-inequalities as a tool to explore non-classical physical behaviours, in this paper we analyze what one can expect to find in many-body quantum physics. Concretely, framing the usual correlation scenarios as a concrete spin-lattice, we want to know whether or not it is possible to violate a Bell-inequality restricted to this scenario. Using clustering theorems, we are able to show that a large family of quantum many-body systems behave almost locally, violating Bell-inequalities (if so) only by a non-significant amount. We also provide examples, explain some of our assumptions via counter-examples and present all the proofs for our theorems. We hope the paper is self-contained.

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Carlos H. S. Vieira, Cristhiano Duarte, Raphael C. Drumond, Marcelo Terra Cunha. 2020-06-09. Bell Non-Locality in Many Body Quantum Systems with Exponential Decay of Correlations. https://doi.org/10.1007/s13538-021-00998-1

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