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Next: THE GLUON ACTION Up: lattice gauge autocorrelations Previous: NOTATION

MOTIVATION

Recently it has become apparent that coarse anisotropic lattices with can be very useful in performing accurate Monte Carlo simulations of QCD at low computational cost. This is especially true when modeling heavy quantum states of QCD -- like glueballs, for example. Because of the exponential fall off of the signal, small gives better resolution of the correlators at an early time step. On the other hand, should be kept relatively large because of critical slowing down.

Since the anisotropy of the lattice breaks the Euclidean invariance of the continuum theory, it induces temporal and spatial correlation lengths which scale as

so that .

On the other hand, the autocorrelations in Monte Carlo updates are proportional to a power of the correlation length

 

where theoretically n=2 for local stochastic updates and n=0 for cluster/overrelaxation updates.

In practice, different lattice operators will have very different autocorrelation times, and we expect operators that couple strongly to to have larger . Unfortunately ``interesting operators'' in lattice QCD, like those for glueballs, live in the spatial domain and scale with which is large.

This work tries to address the issue of the scaling behavior of different gluon operators on anisotropic lattices, and their relevance to the problem of MC algorithm optimization.



Constantine Nenkov
Fri Aug 23 12:05:10 EDT 1996