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arXiv · 1004.0951

All maps equivalent to a given map, completely positive or not

Yong-Cheng Ou·Mark S. Byrd
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Abstract

A dynamical map is a map which takes one density operator to another. Such a map can be written in an operator-sum representation (OSR) using a spectral decomposition. The method of the construction applies to more general maps which need not be completely positive. The OSR not unique; there is a freedom to choose the set of operators in the OSR differently, yet still obtain the same map. Here we identify all maps which are equivalent to a given map. Whereas the freedom for completely positive maps is unitary, the freedom for maps which are not necessarily completely positive is pseudo-unitary.

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Yong-Cheng Ou, Mark S. Byrd. 2010-04-29. All maps equivalent to a given map, completely positive or not. https://doi.org/10.1103/physreva.82.022325

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