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arXiv · quant-ph/0512199

Multiparticle entanglement and ranks of density matrices

Bo Chong·Hellmut Keiter·Joachim Stolze
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Abstract

Based on the ranks of reduced density matrices, we derive necessary conditions for the separability of multiparticle arbitrary-dimensional mixed states, which are equivalent to sufficient conditions for entanglement. In a similar way we obtain necessary conditions for the separability of a given mixed state with respect to partitions of all particles of the system into subsets. The special case of pure states is discussed separately.

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Bo Chong, Hellmut Keiter, Joachim Stolze. 2005-12-22. Multiparticle entanglement and ranks of density matrices. https://arxiv.org/abs/quant-ph/0512199

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