Critical slowing-down in SU(2) Landau-gauge-fixing algorithms at β=∞ Original Research Article

We evaluate numerically and analytically the dynamic critical exponent z for five gauge-fixing algorithms in SU(2) lattice Landau-gauge theory by considering the case β=∞. Numerical data are obtained in two, three and four dimensions. Results are in agreement with those obtained previously at finite β in two dimensions. The theoretical analysis, valid for any dimension d, helps us clarify the tuning of these algorithms. We also study generalizations of the overrelaxation algorithm and of the stochastic overrelaxation algorithm and verify that we cannot have a dynamic critical exponent z smaller than 1 with these local algorithms. Finally, the analytic approach is applied to the so-called λ-gauges, again at β=∞, and verified numerically for the two-dimensional case.