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DOE OSTI · 21407923

Unitary-process discrimination with error margin

Hashimoto, T·Hayashi, A·Horibe, M·Hayashi, M
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Abstract

We investigate a discrimination scheme between unitary processes. By introducing a margin for the probability of an erroneous guess, this scheme interpolates the two standard discrimination schemes: minimum-error and unambiguous discrimination. We present solutions for two cases. One is the case of two unitary processes with general prior probabilities. The other is the case with a group symmetry: The processes comprise a projective representation of a finite group. In the latter case, we found that unambiguous discrimination is a kind of 'all or nothing': The maximum success probability is either 0 or 1. We also thoroughly analyze how entanglement with an auxiliary system improves discrimination performance.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSERRORSMATHEMATICAL SOLUTIONSPROBABILITYQUANTUM ENTANGLEMENTSYMMETRY

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Hashimoto, T, Hayashi, A, Horibe, M, Hayashi, M. 2010-06-15. Unitary-process discrimination with error margin. https://doi.org/10.1103/physreva.81.062327

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