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arXiv · 2211.12522

Smooth Metric Adjusted Skew Information Rates

Koji Yamaguchi·Hiroyasu Tajima
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Abstract

Metric adjusted skew information, induced from quantum Fisher information, is a well-known family of resource measures in the resource theory of asymmetry. However, its asymptotic rates are not valid asymmetry monotone since it has an asymptotic discontinuity. We here introduce a new class of asymmetry measures with the smoothing technique, which we term smooth metric adjusted skew information. We prove that its asymptotic sup- and inf-rates are valid asymptotic measures in the resource theory of asymmetry. Furthermore, it is proven that the smooth metric adjusted skew information rates provide a lower bound for the coherence cost and an upper bound for the distillable coherence.

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Koji Yamaguchi, Hiroyasu Tajima. 2022-11-22. Smooth Metric Adjusted Skew Information Rates. https://doi.org/10.22331/q-2023-05-22-1012

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