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arXiv · 1804.04654

A panoply of Schwinger-Keldysh transport

Kristan Jensen·Raja Marjieh·Natalia Pinzani-Fokeeva·Amos Yarom
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Abstract

We classify all possible allowed constitutive relations of relativistic fluids in a statistical mechanical limit using the Schwinger-Keldysh effective action for hydrodynamics. We find that microscopic unitarity enforces genuinely new constraints on the allowed transport coefficients that are invisible in the classical hydrodynamic description; they are not implied by the second law or the Onsager relations. We term these conditions Schwinger-Keldysh positivity and provide explicit examples of the various allowed terms.

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Kristan Jensen, Raja Marjieh, Natalia Pinzani-Fokeeva, Amos Yarom. 2018-04-12. A panoply of Schwinger-Keldysh transport. https://doi.org/10.21468/scipostphys.5.5.053

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