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Australian Journal of Physics

Variational Wavefunctions for Non-compact U(1) Lattice Gauge Theory: Comparison with Exact Result

D O'Shaughnessy, Conrad J. Burden

Published Apr 1, 1993• 0 citations
Publisher

Abstract

Estimates of the ground state wavefunction of (2+ 1 )-dimensional non-compact U (1) Hamiltonian lattice gauge theory are found in terms of variational wavefunctions with up to four parameters. These wavefunctions are compared with the exact ground state as a test of the accuracy of the method.
DOI
10.1071/ph930231

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The SU(2) Hamiltonian lattice gauge theory is shown explicitly to be equivalent to a nonrelativistic quantum many-body problem in S3{S}^{3}S3. By exploiting this equivalence, a many-body Monte Carlo algorithm is devised to solve for its ground-state properties. To the extent that a trial wave function consisting of a product of single-plaquette functions is a good approximation to the exact ground state, the present Monte Carlo method is shown to be an efficient means of calculating the ground-state energy with high precision.