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Deciding whether a quantum state has secret correlations is an NP-complete problem

Jae-Weon Lee·DoYong Kwon·Jaewan Kim
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Abstract

From the NP-hardness of the quantum separability problem and the relation between bipartite entanglement and the secret key correlations, it is shown that the problem deciding whether a given quantum state has secret correlations in it or not is in NP-complete.

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Jae-Weon Lee, DoYong Kwon, Jaewan Kim. 2006-12-07. Deciding whether a quantum state has secret correlations is an NP-complete problem. https://arxiv.org/abs/quant-ph/0612052

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