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arXiv · 1207.2827

Quantum entanglement and approximation by positive matrices

Xiaofen Huang·Naihuan Jing
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Abstract

We give an exact solution to the nonlinear optimization problem of approximating a Hermitian matrix by positive semi-definite matrices. Our algorithm was then used to judge whether a quantum state is entangled or not. We show that the exact approximation of a density matrices by tensor product of positive semi-definite operators is determined by the additivity property of the density matrix.

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Xiaofen Huang, Naihuan Jing. 2012-07-12. Quantum entanglement and approximation by positive matrices. https://arxiv.org/abs/1207.2827

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