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arXiv · 2212.07434

Rigorous bounds on transport from causality

Michal P. Heller·Alexandre Serantes·Michał Spaliński·Benjamin Withers
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Abstract

We use causality to derive a number of simple and universal constraints on dispersion relations, which describe the location of singularities of retarded two-point functions in relativistic quantum field theories. We prove that all causal dissipative dispersion relations have a finite radius of convergence. We then give two-sided bounds on all transport coefficients in units of this radius, including an upper bound on diffusivity.

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Michal P. Heller, Alexandre Serantes, Michał Spaliński, Benjamin Withers. 2022-12-14. Rigorous bounds on transport from causality. https://doi.org/10.1103/physrevlett.130.261601

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