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arXiv · 2609.23946

A constructive violation of additivity of minimum output von Neumann entropy

Laura Shou·Alexey V. Gorshkov
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Abstract

We give an explicit non-random example of nonadditivity of minimum output von Neumann entropy. The proof uses a finite-dimensional construction which imitates free Haar unitary behavior. The same channel also gives a violation of additivity for the minimum output Rényi-$p$ entropy for any $1\le p\le\infty$.

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Laura Shou, Alexey V. Gorshkov. 2026-09-20. A constructive violation of additivity of minimum output von Neumann entropy. https://arxiv.org/abs/2609.23946

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