Vortices in SO(3)xZ(2) simulations
  We study the configuration space of the Tomboulis $SO(3) \times Z(2)$ formulation with periodic boundary conditions. The dynamical variables are constrained by the required coincidence of Z(2) and SO(3) monopoles. We propose an update algorithm that satisfies the constraints and is straightforward to implement. We further prove that this it reaches all configurations. We show how the boundary conditions put constraints on the configuration space.   We measure gauge invariant vortex counters for "thin",   "thick" and "hybrid" vortex sheets. For comparison we also measure projection vortex counters defined in the maximal center gauge. 
A. Alexandru and Richard W. Haymaker (Louisiana State University)