Centre vortices and their friends

We report two probes of centre vortices in pure SU(2). First, we attempt to generate plaquette-size Z(2) vortices in a quasi-random way to compare the structure with those of projected centre vortices from the full theory; our prescription is, however, not completely random. Second, we test the effect of centre vortices on Wilson loops as a function of position. This shows clearly that the major effect is the piercing of the Wilson loop regardless of the position of the vortex inside.