Speaker
Description
Nonthermal fixed points are universal, attractive stages in the far-from-equilibrium dynamics of quantum many-body systems. Static Nonthermal Fixed points are well understood and have been experimentally observed in cold-atom experiments. They have been theoretically predicted in models of early-universe cosmology and ultra-relativistic heavy-ion collisions. In these set-ups, expansion plays an important role. In this talk I will present results that show how Nonthermal Fixed Points in expanding backgrounds can be understood as ideal hydrodynamic manifestations of their non-expanding counterparts. In Bjorken flow, we find that deviations from the ideal behavior can be described by viscous hydrodynamic corrections. This constitutes a clear example of far-from-equilibrium hydrodynamic behavior. A consequence of this finding is that we can study the anisotropic expanding NTFP, relevant for the first stage of BMSS bottom-up thermalization scenario for heavy-ion collisions, by considering an anisotropic non-expanding NTFP. I will discuss how this could be studied in cold-atom experiments.