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arXiv · 0711.0664

Optimality of minimum-error discrimination by the no-signalling condition

Joonwoo Bae·Jae-Weon Lee·Jaewan Kim·Won-Young Hwang
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Abstract

In this work we relate the well-known no-go theorem that two non-orthogonal (mixed) quantum states cannot be perfectly discriminated, to the general principle in physics, the no-signalling condition. In fact, we derive the minimum error in discrimination between two quantum states, using the no-signalling condition.

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Joonwoo Bae, Jae-Weon Lee, Jaewan Kim, Won-Young Hwang. 2007-11-05. Optimality of minimum-error discrimination by the no-signalling condition. https://doi.org/10.1103/physreva.78.022335

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