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Conceptual Inadequacy of the Shannon Information in Quantum Measurements

Caslav Brukner·Anton Zeilinger
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Abstract

In a classical measurement the Shannon information is a natural measure of our ignorance about properties of a system. There, observation removes that ignorance in revealing properties of the system which can be considered to preexist prior to and independent of observation. Because of the completely different root of a quantum measurement as compared to a classical measurement conceptual difficulties arise when we try to define the information gain in a quantum measurement using the notion of Shannon information. The reason is that, in contrast to classical measurement, quantum measurement, with very few exceptions, cannot be claimed to reveal a property of the individual quantum system existing before the measurement is performed.

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Caslav Brukner, Anton Zeilinger. 2002-04-05. Conceptual Inadequacy of the Shannon Information in Quantum Measurements. https://doi.org/10.1103/physreva.63.022113

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