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Compatibility of quantum states

David Poulin·Robin Blume-Kohout
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Abstract

We introduce a measure of the compatibility between quantum states--the likelihood that two density matrices describe the same object. Our measure is motivated by two elementary requirements, which lead to a natural definition. We list some properties of this measure, and discuss its relation to the problem of combining two observers' states of knowledge.

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David Poulin, Robin Blume-Kohout. 2002-05-07. Compatibility of quantum states. https://doi.org/10.1103/physreva.67.010101

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