Wilson loop distributions, higher representations and centre dominance in SU(2)

Abstract

To help understand the centre dominance picture of confinement, we look at Wilson loop distributions in pure SU(2) lattice gauge theory. A strong coupling approximation for the distribution is developed to use for comparisons. We perform a Fourier expansion of the distribution: centre dominance here corresponds to suppression of odd terms beyond the first. The Fourier terms correspond to SU(2) representations; hence Casimir scaling behaviour leads to centre dominance. We examine the positive plaquette model, where only thick vortices are present. We show that a simple picture of random, non-interacting centre vortices gives a string tension about 3/4 of the measured value. Finally, we attempt to limit confusion about the adjoint representation.