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arXiv · 1408.6172

Information-theoretic constraints on correlations with indefinite causal order

Issam Ibnouhsein·Alexei Grinbaum
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Abstract

Reconstructions of quantum theory usually implicitly assume that experimental events are ordered within a global causal structure. The process matrix framework accommodates quantum correlations that violate an inequality verified by all causally ordered correlations. Using a generalized probabilistic framework, we propose three principles constraining bipartite correlations to the quantum bound. Our approach highlights the role of a measure of dependence other than mutual information for an information-theoretic reconstruction of causal structures in quantum theory.

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Issam Ibnouhsein, Alexei Grinbaum. 2015-11-23. Information-theoretic constraints on correlations with indefinite causal order. https://doi.org/10.1103/physreva.92.042124

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