Shear viscosity of a relativistic scalar field from functional renormalization

2025/12/21 by Tim Stoetzel, Stefan Floerchinger, Stoetzel, Tim +1
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #FOS: Physical sciences #High Energy Physics - Theory (hep-th) #High-Energy Particle Collisions Research

paper · doi:10.48550/arxiv.2512.18740

openalex publication_date 2025/12/21 · openalex created_date 2025/12/24 · openalex updated_date 2026/07/28

Abstract

Renormalization group flow equations of the fluid dynamical shear viscosity transport coefficient of a relativistic real scalar field are derived. The flowing effective action contains branch cut contributions to the self energy and interaction vertex in the symmetric phase. We demonstrate how the flow equation method can systematically extend the perturbative resummation schemes. We show that our truncation is in that sense a minimal scheme in which a reliable viscosity coefficient is obtained.

Citations

• Energy-momentum response to metric perturbations in the fluid dynamic regime
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• Relativistic Fluid Dynamics In and Out of Equilibrium -- Ten Years of\n Progress in Theory and Numerical Simulations of Nuclear Collisions
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