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Continuous optimal ensembles II. Reducing the separability condition to numerical equations

Roman R. Zapatrin
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Abstract

A density operator of a bipartite quantum system is called robustly separable if it has a neighborhood of separable operators. Given a bipartite density matrix, its property to be robustly separable is reduced, using the continuous ensemble method, to a finite number of numerical equations. The solution of this system exists for any robustly separable density operator and provides its representation by a continuous mixture of pure product states.

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Roman R. Zapatrin. 2005-04-06. Continuous optimal ensembles II. Reducing the separability condition to numerical equations. https://arxiv.org/abs/quant-ph/0504034

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