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arXiv · 1606.09241

Quantum superpositions of "common-cause" and "direct-cause" causal structures

Adrien Feix·Časlav Brukner
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Abstract

The constraints arising for a general set of causal relations, both classically and quantumly, are still poorly understood. As a step in exploring this question, we consider a coherently controlled superposition of "direct-cause" and "common-cause" relationships between two events. We propose an implementation involving the spatial superposition of a mass and general relativistic time dilation. Finally, we develop a computationally efficient method to distinguish such genuinely quantum causal structures from classical (incoherent) mixtures of causal structures and show how to design experimental verifications of the nonclassicality of a causal structure.

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Adrien Feix, Časlav Brukner. 2016-06-29. Quantum superpositions of "common-cause" and "direct-cause" causal structures. https://doi.org/10.1088/1367-2630/aa9b1a

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