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arXiv · 2007.00417

Uniform continuity bounds for characteristics of multipartite quantum systems

M. E. Shirokov
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Abstract

We consider universal methods for obtaining (uniform) continuity bounds for characteristics of multipartite quantum systems. We pay a special attention to infinite-dimensional multipartite quantum systems under the energy constraints. By these methods we obtain continuity bounds for several important characteristics of a multipartite quantum state: the quantum (conditional) mutual information, the squashed entanglement, the c-squashed entanglement and the conditional entanglement of mutual information. The continuity bounds for the multipartite quantum mutual information are asymptotically tight for large dimension/energy. The obtained results are used to prove the asymptotic continuity of the $n$-partite squashed entanglement, c-squashed entanglement and the conditional entanglement of mutual information under the energy constraints.

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M. E. Shirokov. 2020-07-01. Uniform continuity bounds for characteristics of multipartite quantum systems. https://doi.org/10.1063/5.0055155

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