Spinodal decomposition in high temperature gauge theories

After a rapid increase in temperature across the deconfinement temperature Td, pure gauge theories exhibit unstable long wavelength fluctuations in the approach to equilibrium. This phenomenon is analogous to spinodal decomposition observed in condensed matter physics, and also seen in models of disordered chiral condensate formation. At high temperature, the unstable modes occur only in the range 0≤k ≤kc, where kc is on the order of the Debye screening mass mD. Equilibration always occurs via spinodal decomposition for SU(2) at temperatures T>Td and for SU(3) for T≫Td. For SU(3) at temperatures T≳Td, nucleation may replace spinodal decomposition as the dominant equilibration mechanism. Monte Carlo simulations of SU(2) lattice gauge theory exhibit the predicted phenomena. The observed value of kc is in reasonable agreement with a value predicted from previous lattice measurements of mD.