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Quantum properties of classical Fisher information

Michael J. W. Hall
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Abstract

The Fisher information of a quantum observable is shown to be proportional to both (i) the difference of a quantum and a classical variance, thus providing a measure of nonclassicality; and (ii) the rate of entropy increase under Gaussian diffusion, thus providing a measure of robustness. The joint nonclassicality of position and momentum observables is shown to be complementary to their joint robustness in an exact sense.

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Michael J. W. Hall. 1999-12-13. Quantum properties of classical Fisher information. https://doi.org/10.1103/physreva.62.012107

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