New Cluster Expansion Method in Lattice Gauge Theory

Localization in Lattice Gauge Theory and a New Multigrid Method

We show numerically that the lowest eigenmodes of the 2-dimensional Laplace-operator with SU(2) gauge couplings are strongly localized. A connection is drawn to the Anderson-Localization problem. A new Multigrid algorithm, capable to deal with these modes, shows no critical slowing down for this problem.

The t expansion and SU(2) lattice gauge theory.

Lattice Gauge Theory

Supercomputers have recently become a crucial tool for the quantum field the-orist. Applied to the formalism of lattice gauge theory, numerical simulations are providing fundamental quantitative information about the interactions of quarks, the fundamental constituents of those particles which experience nuclear interactions. Perhaps most strikingly, these simulations have provided convincing e...

The Shifted Coupled Cluster Method : a New Approach to Hamiltonian Lattice Gauge Theories

It is shown how to adapt the non-perturbative coupled cluster method of many-body theory so that it may be successfully applied to Hamiltonian lattice SU (N) gauge theories. The procedure involves first writing the wavefunctions for the vacuum and excited states in terms of linked clusters of gauge invariant excitations of the strong coupling vacuum. The fundamental approximation scheme then co...

Coupled cluster method in Hamiltonian lattice field theory

The coupled cluster or exp(S! form of the eigenvalue problem for a lattice Hamiltonian QCD ~without quarks! is investigated. A new construction prescription is given for the calculation of the relevant coupled cluster matrix elements with respect to an orthogonal and independent loop space basis. The method avoids the explicit introduction of gauge group coupling coefficients by mapping the eig...