Plasmon properties in classical lattice gauge theory

In order to investigate the features of the classical approximation at high temperatures for real time correlation functions, the plasmon frequencies and damping rates were recently computed numerically in the SU(2) + Higgs model and in the pure SU(2) theory. We compare the lattice results with leading order hard thermal loop resummed perturbation theory. In the broken phase of the SU(2) + Higgs model, we show that the lattice results can be reproduced and that the lattices used are too coarse to observe some important plasmon effects. In the symmetric phase, the main qualitative features of the lattice results can also be understood. In the pure SU(2) theory, on the other hand, there are discrepancies which might point to larger Landau and plasmon damping effects than indicated by perturbation theory. (C) 1998 Elsevier Science B.V.