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arXiv · 1710.11387

Hierarchy in temporal quantum correlations

Huan-Yu Ku·Shin-Liang Chen·Neill Lambert·Yueh-Nan Chen·Franco Nori
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Abstract

Einstein-Podolsky-Rosen (EPR) steering is an intermediate quantum correlation that lies in between entanglement and Bell non-locality. Its temporal analogue, temporal steering, has recently been shown to have applications in quantum information and open quantum systems. Here, we show that there exists a hierarchy among the three temporal quantum correlations: temporal inseparability, temporal steering, and macrorealism. Given that the temporal inseparability can be used to define a measure of quantum causality, similarly the quantification of temporal steering can be viewed as a weaker measure of direct cause and can be used to distinguish between direct cause and common cause in a quantum network.

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Huan-Yu Ku, Shin-Liang Chen, Neill Lambert, Yueh-Nan Chen, Franco Nori. 2017-10-31. Hierarchy in temporal quantum correlations. https://doi.org/10.1103/physreva.98.022104

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