2025/04/26 by Jürgen Berges, Berges, Jürgen, Gabriel S. Denicol +5
Mathematics · Physics and Astronomy · #Dust and Plasma Wave Phenomena #FOS: Physical sciences #Gas Dynamics and Kinetic Theory #High Energy Physics - Theory (hep-th) #High-Energy Particle Collisions Research #Quantum Gases (cond-mat.quant-gas)
paper · pdf · doi:10.48550/arxiv.2504.18754
openalex publication_date 2025/04/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Nonthermal fixed points are paradigmatic far-from-equilibrium phenomena of relevance to high-energy physics, cosmology, and cold atomic gases. We propose that, despite their intrinsically nonequilibrium nature, nonthermal fixed points give rise to hydrodynamic excitations otherwise known in the vicinity of thermal equilibrium. As a result, nonthermal fixed points can also be characterized by transport coefficients, such as a far-from-equilibrium, and therefore manifestly time-dependent, incarnation of shear viscosity. We corroborate our proposal with explicit studies using relativistic kinetic theory with binary collisions of massless particles in the 14-moment approximation and comparisons to QCD kinetic theory simulations.