Information-theoretic constraints on correlations with indefinite causal order

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.

8 pages

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Cited by in corpus (10)

• Causal and causally separable processes
• The simplest causal inequalities and their violation
• The space of logically consistent classical processes without causal order
• Channel capacity enhancement with indefinite causal order
• How device-independent approaches change the meaning of physical theory
• Classical Communications with Indefinite Causal Order for $N$ completely depolarizing channels
• Device-independent test of causal order and relations to fixed-points
• The entropic approach to causal correlations
• Biased Non-Causal Game
• Remote Creation of Quantum Coherence via Indefinite Causal Order