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Computational Complexity Measures of Multipartite Quantum Entanglement

Tomoyuki Yamakami
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Abstract

We shed new light on entanglement measures in multipartite quantum systems by taking a computational-complexity approach toward quantifying quantum entanglement with two familiar notions--approximability and distinguishability. Built upon the formal treatment of partial separability, we measure the complexity of an entangled quantum state by determining (i) how hard to approximate it from a fixed classical state and (ii) how hard to distinguish it from all partially separable states. We further consider the Kolmogorovian-style descriptive complexity of approximation and distinction of partial entanglement.

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Tomoyuki Yamakami. 2003-08-13. Computational Complexity Measures of Multipartite Quantum Entanglement. https://arxiv.org/abs/quant-ph/0308072

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