Speaker
Description
We study universal aspects of critical dynamics in QCD matter within our real-time formulation of the functional renormalization group (FRG) for dynamical systems with reversible mode couplings. The two most relevant ones for QCD describe the dynamics across the chiral transition and that near the QCD critical point, in the dynamical universality classes of Models G and H, respectively. We use non-perturbative FRG flow equations to compute the dynamic critical exponents of the corresponding kinetic coefficients and their universal dynamic scaling functions with special emphasis on commonalities and differences between the two dynamic models such as strong versus weak dynamic scaling relations. The real-time FRG for critical dynamics is shown to describe the universal behavior of pion damping and iso-(axial-)vector charge diffusion in the chiral transition, and that of thermal diffusivity and shear viscosity in the vicinity of the QCD critical point.