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Critical Slowing-Down in SU(2) Landau-Gauge-Fixing Algorithms at beta = infinity

Attilio Cucchieri·Tereza Mendes
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Abstract

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 $β= \infty$. 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 $β= \infty$, and verified numerically for the two-dimensional case.

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Attilio Cucchieri, Tereza Mendes. 2003-05-15. Critical Slowing-Down in SU(2) Landau-Gauge-Fixing Algorithms at beta = infinity. https://doi.org/10.1016/s0010-4655(03)00279-0

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