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arXiv · 1210.3424

A sufficient condition of violating the SPA conjecture

Bang-Hai Wang·Dong-Yang Long
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Abstract

Based on the general form of entanglement witnesses constructed from separable states, we first show a sufficient condition of violating the structural physical approximation (SPA) conjecture [Phys. Rev. A 78, 062105 (2008)]. Then we discuss the SPA conjecture for decomposable entanglement witnesses. Moreover, we make geometric illustrations of the connection between entanglement witnesses and the sets of quantum states, separable states, and entangled states comparing with planes and vectors in Euclidean space.

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Bang-Hai Wang, Dong-Yang Long. 2012-10-12. A sufficient condition of violating the SPA conjecture. https://arxiv.org/abs/1210.3424

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