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arXiv · 2404.09291

Green and Kubo forge the arrow of time

Stefano Baroni
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Abstract

Transport theory describes the response of a macroscopic current to a thermodynamic force, thus producing entropy and apparently violating time-reversal symmetry. In this note I report a pedagogical derivation of the Green-Kubo formula for transport coefficients that highlights the intrinsically dynamical nature of this formula and showcases the relation between the apparent breach of time-reversal symmetry and the non-commutativity of the low-frequency / low-wavevector limits of the conserved-density susceptibilities, from which the formula can be established.

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Stefano Baroni. 2024-04-14. Green and Kubo forge the arrow of time. https://doi.org/10.1080/00268976.2024.2388300

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