Progress in lattice algorithms

The development of Monte Carlo algorithms for generating gauge field configurations with dynamical fermions and methods for extracting the most information from ensembles are summarised.Comment: Lattice2001(plenary) 9 pages, 4 figures. Uses espcrc2.st

Dynamical fermion simulations using Luescher's local bosonic action algorithm

The two-flavour Schwinger model is used to test the local boson action algorithm of M Luescher. The autocorrelation time is found to rise linearly with the number of auxiliary boson fields. An extension to the algorithm is proposed which exactly reproduces the full dynamical partition function for any number of boson fields.Comment: 3 pages - uuencoded PostScript. Contribution to proceedings of Lattice '9

Analytic Smearing of SU(3) Link Variables in Lattice QCD

An analytic method of smearing link variables in lattice QCD is proposed and tested. The differentiability of the smearing scheme with respect to the link variables permits the use of modern Monte Carlo updating methods based on molecular dynamics evolution for gauge-field actions constructed using such smeared links. In examining the smeared mean plaquette and the static quark-antiquark potential, no degradation in effectiveness is observed as compared to link smearing methods currently in use, although an increased sensitivity to the smearing parameter is found.Comment: 8 pages, 4 figures, uses RevTe

Simulating the scalar glueball on the lattice

Techniques for efficient computation of the scalar glueball mass on the lattice are described. Directions and physics goals of proposed future calculations will be outlined.Comment: 9 pages, 3 figures, submitted to the proceedings of the SUNYIT Scalar Mesons workshop (May 2003

SU(3) lattice gauge autocorrelations with anisotropic action

We report results of autocorrelation measurements in pure $SU(3)$ lattice gauge theory. The computations are performed on the {\sc convex spp1200} parallel platform within the {\sc canopy} programming environment. The focus of our analysis is on typical autocorrelation times and optimization of the mixing ratio between overrelaxation and pseudo-heatbath sweeps for generating gauge field configurations. We study second order tadpole-improved approximations of the Wilson action in the gluon sector, which offers the advantage of working on smaller lattices ($8^3~\times~16$ and $6^3~\times$~12~--~30). We also make use of anisotropic lattices, with temporal lattice spacing smaller than the spatial spacing, which prove useful for calculating noisy correlation functions with large spatial lattice discretization (of the order of 0.4 fm).Comment: 4 pages (LaTeX), 7 figures (PostScript), Talk presented at LATTICE96(improvement

In search of a scaling scalar glueball

Anisotropic lattices are an efficient means of studying the glueballs of QCD, however problems arise with simulations of the lightest, scalar state. The mass is strongly dependent on the lattice spacing, even when a mean-field improved gluon action is used. The nature and cause of these errors are discussed and the scaling properties of the scalar from different lattice actions are presented.Comment: LATTICE98(improvement