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arXiv · 1509.06591

Detecting Consistency of Overlapping Quantum Marginals by Separability

Jianxin Chen·Zhengfeng Ji·Nengkun Yu·Bei Zeng
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Abstract

The quantum marginal problem asks whether a set of given density matrices are consistent, i.e., whether they can be the reduced density matrices of a global quantum state. Not many non-trivial analytic necessary (or sufficient) conditions are known for the problem in general. We propose a method to detect consistency of overlapping quantum marginals by considering the separability of some derived states. Our method works well for the $k$-symmetric extension problem in general, and for the general overlapping marginal problems in some cases. Our work is, in some sense, the converse to the well-known $k$-symmetric extension criterion for separability.

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Jianxin Chen, Zhengfeng Ji, Nengkun Yu, Bei Zeng. 2015-09-23. Detecting Consistency of Overlapping Quantum Marginals by Separability. https://doi.org/10.1103/physreva.93.032105

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