Quantum correlations curvature, memory functions, and fundamental bounds

Alexander Kruchkov

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arXiv · 2512.18942

Quantum correlations curvature, memory functions, and fundamental bounds

Alexander Kruchkov

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Abstract

We investigate fundamental bounds on the curvature of quantum correlation functions in imaginary time. Focusing first on topological phases, we show that quantum geometry can qualitatively modify the imaginary-time decay of correlations, leading to nontrivial curvature behavior beyond simple exponential scaling. More generally, we show a universal bound on correlation curvature that holds for interacting systems in thermal equilibrium, and establish connection to leading invariants of the memory-function formalism. Our results identify imaginary-time curvature as a robust probe of intrinsic quantum timescales.

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Alexander Kruchkov. 2025-12-22. Quantum correlations curvature, memory functions, and fundamental bounds. https://arxiv.org/abs/2512.18942

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