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DOE OSTI · 2326352

N-particle irreducible actions for stochastic fluids

Chao, Jingyi·Schäfer, Thomas
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Abstract

We construct one- and two-particle irreducible (1PI and 2PI) effective actions for the stochastic fluid dynamics of a conserved density undergoing diffusive motion. We compute the 1PI action in one-loop order and the 2PI action in two-loop approximation. We derive a set of Schwinger-Dyson equations and regularize the resulting equations using Pauli-Villars fields. We numerically solve the Schwinger-Dyson equations for a non-critical fluid. We find that higher-loop effects summed by the Schwinger-Dyson renormalize the non-linear coupling. We also find indications of a diffuson-cascade, the appearance of n-loop correction with smaller and smaller exponential suppression.

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BibTeXRIS

Chao, Jingyi, Schäfer, Thomas. 2023-06-12. N-particle irreducible actions for stochastic fluids. https://doi.org/10.1007/jhep06(2023)057

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