Speaker
Description
We demonstrate the chaoticity inherent in SU(2) gauge theory consisting of soft momentum modes both in and out-of-thermal equilibrium conditions using lattice techniques. The non-equilibrium state has been realized starting from an over-occupied initial condition for low momentum soft gluons whereas the thermal state comprises of strongly interacting soft gluons at temperatures where these are well separated from the hard momentum modes. Spectra of positive Lyapunov exponents is observed in both these states, similar to a chaotic dynamical system. From the Kolmogorov-Sinai entropy rate measured in terms of this spectrum, we estimate a typical time-scale of $\sim 0.50(3)$ fm/c to achieve thermalization at $T\sim 600$ MeV starting from the non-thermal state. Next, we have also studied the sphaleron rate in non-Abelian gauge theories both in and out-of-thermal equilibrium conditions. From the time dependent scaling of the sphaleron rate in non-thermal case within self-similar regime, we have estimated the typical thermalization time for the magnetic gluons relevant for e.g. in the context of early universe.
| Parallel Session (for talks only) | QCD at nonzero temperature and density |
|---|
