Multigrid Monte Carlo with higher cycles in the Sine Gordon model

We study the dynamical critical behavior of multigrid Monte Carlo for the two-dimensional Sine Gordon model on lattices up to 128x128. Using piecewise constant interpolation, we perform a W-cycle (Y=2). We examine whether one can reduce critical slowing down caused by decreasing acceptance rates on large blocks by doing more work on coarser lattices. To this end, we choose a higher cycle with Y=4. The results clearly demonstrate that critical slowing down is not reduced in either case. (orig.)