A comparison of updating algorithms for large N reduced models

Abstract

We investigate Monte Carlo updating algorithms for simulating SU(N ) YangMills fields on a single-site lattice, such as for the Twisted Eguchi-Kawai model (TEK). We show that performing only over-relaxation (OR) updates of the gauge links is a valid simulation algorithm for the Fabricius and Haan formulation of this model, and that this decorrelates observables faster than using heat-bath updates. We consider two different methods of implementing the OR update: either updating the whole SU(N ) matrix at once, or iterating through SU(2) subgroups of the SU(N ) matrix, we find the same critical exponent in both cases, and only a slight difference between the two.

Background field method in the gradient flow

“…(3.3). In terms of the renormalized gauge coupling g in the MS scheme, 24) where b 0 is the one-loop coefficient in the beta function,…”

The meson spectrum of large N gauge theories

“…The gauge field is generated with the TEK probability distribution using the overrelaxation technique explained in Ref. [13]. The results presented here were obtained with N = 289, implyingL = 17.…”

Meson masses and decay constants at large N

“…To test our method, we have simulated the TEK model for N=289, with ℓ 0 = 2. We took two values of inverse For each parameter set, we have calculated meson propagators with 800 configurations, each configuration being separated by 1000 MC sweeps [13]. In the following, all meson masses are obtained from a single hyperbolic cosine fit to the SS correlator in each channel, with the fitting range 6 ≤ n 0 ≤ 12.…”