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arXiv · 2505.00882

The Alicki-Fannes-Winter technique in the quasi-classical settings: advanced version and its applications

M. E. Shirokov
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Abstract

We describe an advanced version of the AFW-technique proposed in [Lett. Math. Phys., 113, 121 (2023)],[Lobachevskii J. Math., 44(6), 2169 (2023)] which allows us to obtain lower semicontinuity bounds, continuity bounds and local lower bounds for characteristics of quantum systems and discrete random variables. We consider applications of the new version of the AFW-technique to several basic characteristics of quantum systems (the von Neumann entropy, the energy-type functionals, the quantum relative entropy, the conditional entropy and the entanglement of formation).

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M. E. Shirokov. 2025-05-01. The Alicki-Fannes-Winter technique in the quasi-classical settings: advanced version and its applications. https://arxiv.org/abs/2505.00882

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