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Quantum State Disturbance vs. Information Gain: Uncertainty Relations for Quantum Information

Christopher A. Fuchs·Asher Peres
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Abstract

When an observer wants to identify a quantum state, which is known to be one of a given set of non-orthogonal states, the act of observation causes a disturbance to that state. We investigate the tradeoff between the information gain and that disturbance. This issue has important applications in quantum cryptography. The optimal detection method, for a given tolerated disturbance, is explicitly found in the case of two equiprobable non-orthogonal pure states.

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Christopher A. Fuchs, Asher Peres. 1995-12-22. Quantum State Disturbance vs. Information Gain: Uncertainty Relations for Quantum Information. https://doi.org/10.1103/physreva.53.2038

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