Wilson Loops, Winding modes, and Domain Walls in Finite Temperature QCD

We discuss the effective action for Polyakov-Wilson loops winding around compact Euclidean time, which serve as order parameters for the finite temperature deconfinement transition in $SU(N)$ Yang-Mills gauge theory. We then apply our results to the study of the high temperature continuation of the confining phase, and to the analysis of certain $Z_N$ domain walls that have been argued to play a role in cosmology. We argue that the free energy of these walls is much larger than previously thought.