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arXiv · 1210.3749

Quantum local asymptotic normality based on a new quantum likelihood ratio

Koichi Yamagata·Akio Fujiwara·Richard D. Gill
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Abstract

We develop a theory of local asymptotic normality in the quantum domain based on a novel quantum analogue of the log-likelihood ratio. This formulation is applicable to any quantum statistical model satisfying a mild smoothness condition. As an application, we prove the asymptotic achievability of the Holevo bound for the local shift parameter.

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Koichi Yamagata, Akio Fujiwara, Richard D. Gill. 2013-11-08. Quantum local asymptotic normality based on a new quantum likelihood ratio. https://doi.org/10.1214/13-aos1147

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