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arXiv · 1804.05498

Violation of a causal inequality in a spacetime with definite causal order

C. T. Marco Ho·Fabio Costa·Christina Giarmatzi·Timothy C. Ralph
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Abstract

Processes with an indefinite causal structure may violate a causal inequality, which quantifies quantum correlations that arise from a lack of causal order. In this paper, we show that when the inequalities are analysed with a Gaussian-localised field theoretic definition of particles and labs, the causal indeterminacy of the fields themselves allows a causal inequality to be violated within the causal structure of Minkowski spacetime. We quantify the violation of the inequality and determine the optimal ordering of observers.

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C. T. Marco Ho, Fabio Costa, Christina Giarmatzi, Timothy C. Ralph. 2018-04-16. Violation of a causal inequality in a spacetime with definite causal order. https://arxiv.org/abs/1804.05498

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