2,272 research outputs found
Some comments on Laplacian gauge fixing
Laplacian gauge fixing was introduced to find a unique representative of the
gauge orbit, which on the lattice could be implemented by a ``finite''
algorithm. What was still lacking was a perturbative formulation of this gauge,
which will be presented here. However, renormalizability is still to be
demonstrated. For torodial and spherical geometries a detailed comparison with
the Landau (or Coulomb) gauge will be made.Comment: Contribution to Lattice '94, 3 pages PostScrip
Monte Carlo calculation for systems consisting of several coordinate patches
I investigate the time step dependence of Monte Carlo simulations for
coordinate-spaces consisting of several patches. It is shown that a naive
kinetic term does not necessarily converge to the same spectrum as a
Hamiltonian calculation. Then an improved kinetic term is presented which
allows one to connect the Monte Carlo and Rayleigh-Ritz results of intermediate
volume SU(2) gauge theory.Comment: 18 page
Instanton Moduli for T**3xR
We review the specific problems that arise when studying instantons on a
torus. We discuss how the Nahm transformation shows that no exact charge one
instanton on T**4 can exist. However, taking one of the directions (the time)
to infinity, it can be shown that vacuum to vacuum tunnelling solutions exist.
A precise description of the moduli space for T**3xR, studied numerically using
lattice techniques, remains an interesting open problem. New is an explicit
application of the Nahm transformation to (anti-)selfdual constant curvature
solutions on T**4 and a discussion of its properties relevant to instantons on
T**3xR.Comment: 12p with 3 figs, uufiles -gz format. Talk at the 29th Int. Symp. on
the Theory of Elem. Part., Buckow, 29 Aug.-2 Sept., 1995
One-loop effective action for SU(2) gauge theory on S^3
We consider the effective theory for the low-energy modes of SU(2) gauge
theory on the three-sphere. By explicitely integrating out the high-energy
modes, the one-loop correction to the hamiltonian for this problem is obtained.
We calculate the influence of this correction on the glueball spectrum.Comment: 12p. latex, 3 PostScript figures included (epsf
Zooming-in on the SU(2) fundamental domain
For SU(2) gauge theories on the three-sphere we analyse the Gribov horizon
and the boundary of the fundamental domain in the 18 dimensional subspace that
contains the tunnelling path and the sphaleron and on which the energy
functional is degenerate to second order in the fields. We prove that parts of
this boundary coincide with the Gribov horizon with the help of bounds on the
fundamental modular domain.Comment: 19p., 6 figs. appended in PostScript (uuencoded), preprint
INLO-PUB-12/93. Revision: ONLY change is a much more economic PostScript code
for figures 1-4 (with apologies
The Witten Index Beyond the Adiabatic Approximation
We attempt to deal with the orbifold singularities in the moduli space of
flat connections for supersymmetric gauge theories on the torus. At these
singularities the energy gap in the transverse fluctuations vanishes and the
resulting breakdown of the adiabatic approximation is resolved by considering
the full set of zero-momentum fields. These can not be defined globally, due to
the problem of Gribov copies. For this reason we restrict the fields to the
fundamental domain, containing no gauge copies, but requiring a boundary
condition in field space.Comment: 29 pages, latex, 6 figures (in 9 parts); now including numerical
results for the wave function, version as it will appear in the Michael
Marinov Memorial Volume, "Multiple facets of quantization and supersymmetry",
edited by M. Olshanetsky and A. Vainshtein (World Scientific
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