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Optimal distinction between non-orthogonal quantum states

Asher Peres·Daniel Terno
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Abstract

Given a finite set of linearly independent quantum states, an observer who examines a single quantum system may sometimes identify its state with certainty. However, unless these quantum states are orthogonal, there is a finite probability of failure. A complete solution is given to the problem of optimal distinction of three states, having arbitrary prior probabilities and arbitrary detection values. A generalization to more than three states is outlined.

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Asher Peres, Daniel Terno. 1998-04-12. Optimal distinction between non-orthogonal quantum states. https://doi.org/10.1088/0305-4470/31/34/013

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