Purification of impure density operators and the recovery of entanglements

V. I. Man'ko; G. Marmo; E. C. G. Sudarshan; F. Zaccaria

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Purification of impure density operators and the recovery of entanglements

V. I. Man'ko·G. Marmo·E. C. G. Sudarshan·F. Zaccaria

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Abstract

The need to retain the relative phases in quantum mechanics implies an addition law parametrized by a phase of two density operators required for the purification of a density matrix. This is shown with quantum tomography and the Wigner function. Entanglement is determined in terms of phase dependent multiplication.

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V. I. Man'ko, G. Marmo, E. C. G. Sudarshan, F. Zaccaria. 1999-10-18. Purification of impure density operators and the recovery of entanglements. https://arxiv.org/abs/quant-ph/9910080

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