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arXiv · 2603.14025

Quantum Dynamical Entropy and Dissipative Information Flows

Giovanni Nichele·Fabio Benatti
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Abstract

The Alicki-Lindblad-Fannes dynamical (ALF) entropy measures the rate at which new information is gathered about a quantum system by inspecting its long-time evolution. We propose an extension of the ALF entropy to open quantum dynamics as a measure of back-flow of information from the environment. Such a proposal is stronger than the existing ones based only on the open system reduced dynamics. In the case of a qubit collisionally coupled to a classical spin chain, we obtain an exact expression for the $\textit{open-system ALF entropy}$ explicitly depending on the environment correlations. An extreme case shows how the information flow from environment to system corresponds to vanishing entropy production as for reversible finite quantum systems.

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Giovanni Nichele, Fabio Benatti. 2026-03-14. Quantum Dynamical Entropy and Dissipative Information Flows. https://arxiv.org/abs/2603.14025

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