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Negative entropy and information in quantum mechanics

N. J. Cerf·C. Adami
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Abstract

A framework for a quantum mechanical information theory is introduced that is based entirely on density operators, and gives rise to a unified description of classical correlation and quantum entanglement. Unlike in classical (Shannon) information theory, quantum (von Neumann) conditional entropies can be negative when considering quantum entangled systems, a fact related to quantum non-separability. The possibility that negative (virtual) information can be carried by entangled particles suggests a consistent interpretation of quantum informational processes.

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N. J. Cerf, C. Adami. 1997-10-30. Negative entropy and information in quantum mechanics. https://doi.org/10.1103/physrevlett.79.5194

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