Non-Markovian and Thermodynamic Signatures in the Classicality Assessment via Kolmogorov Consistency

TL;DR

This paper links the violation of Kolmogorov consistency to non-Markovianity and quantum non-classicality in open quantum systems, providing a unified framework connecting information, thermodynamics, and temporal quantum correlations.

Contribution

It establishes a direct analytical connection between KCC violation and non-Markovianity, and relates these to thermodynamic and information-theoretic quantities in quantum dynamics.

Findings

KCC violation correlates with non-Markovianity and quantum non-classicality.

Quantitative links between KCC violation and thermodynamic measures like entropy production.

Formal correspondences between KCC violation, Leggett-Garg inequality, and Kirkwood-Dirac negativity.

Abstract

The Kolmogorov consistency condition (KCC) defines the statistical boundary between classical and quantum dynamics. Its violation signifies the breakdown of a classical Markov description of temporal correlations. In this work, we establish a direct analytical connection between KCC violation and non-Markovianity in open quantum dynamics, revealing how memory effects manifest as departures from classical probabilistic consistency. Within a generic two-level open quantum system framework, we establish quantitative connections between the magnitude of KCC violation and key information-theoretic and thermodynamic quantities, such as mutual information, the Fano factor, heat exchange, and entropy production rate, thereby enabling a thermodynamic interpretation of temporal quantum correlations. Furthermore, we uncover formal correspondences between KCC violation, the Leggett-Garg inequality, and the negativity of the Kirkwood-Dirac quasi-distribution, identifying them as complementary witnesses of temporal quantum non-classicality. Our results thus provide a unified framework linking information-theoretic, thermodynamic, and temporal indicators of quantumness in open quantum systems.