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arXiv · 2609.23399

Spin density from second order transport in fluids

Domingo Gallegos·Roi Klein·Amos Yarom
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Abstract

We study the hydrodynamics of a charged fluid with spin degrees of freedom. We argue that, in a conformal field theory in 3+1 dimensions, the spin density is related to a linear combination of standard second-order transport coefficients, and an additional term quadratic in the gauge- and mixed gauge-gravitational anomaly coefficients. We compute the spin density in several free and holographic theories and compare the results.

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Domingo Gallegos, Roi Klein, Amos Yarom. 2026-09-20. Spin density from second order transport in fluids. https://arxiv.org/abs/2609.23399

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