30 research outputs found
Dual vortices in Abelian projected SU(2) in the Polyakov gauge
We study dual Abrikosov vortices in Abelian projected SU(2) gauge theory in
the Polyakov gauge. We show that vortices are present in this gauge but they
are suppressed with respect to the maximal Abelian gauge. We interpret this
difference in terms of the shielding of the electric charge by the charged
coset fields.Comment: Talk presented at LATTICE96(topology), 3 pages, latex, 4 eps figures,
uses epsfig and espcrc2.sty (included
SU(2) Flux Distributions on Finite Lattices
We studied SU(2) flux distributions on four dimensional euclidean lattices
with one dimension very large. By choosing the time direction appropriately we
can study physics in two cases: one is finite volume in the zero temperature
limit, another is finite temperature in the the intermediate to large volume
limit. We found that for cases of beta > beta crit there is no intrinsic string
formation. Our lattices with beta > beta crit belong to intermediate volume
region, and the string tension in this region is due to finite volume effects.
In large volumes we found evidence for intrinsic string formation.Comment: 21 pages text, 12 pages of postscript figure
Structure of Abrikosov Vortices in SU(2) Lattice Gauge Theory
We calculate the electric flux and magnetic monopole current distribution in
the presence of a static quark-antiquark pair for SU(2) lattice gauge theory in
the maximal Abelian gauge. The current distribution confines the flux in a dual
Abrikosov vortex whose core size is comparable to the flux penetration depth.
The observed structure is described by a dual Ginzburg-Landau model.Comment: 15 pages, latex file, three figure postscript files appended, Report
No. LSUHEP No. 138-199
SU(3) Flux Tubes in a Model of the stochastic Vacuum
We calculate the squared gluon field strengths of a heavy q--pair in the model of the stochastic vacuum. We observe that with
increasing separation a chromoelectric flux tube is built. The properties of
the emerging flux tube are investigated.Comment: 14, epsf, HD-THEP-94-3
Vortex waistlines and long range fluctuations
We examine the manner in which a linear potential results from fluctuations
due to vortices linked with the Wilson loop. Our discussion is based on exact
relations and inequalities between the Wilson loop and the vortex and electric
flux order parameters. We show that, contrary to the customary naive picture,
only vortex fluctuations of thickness of the order of the spatial linear size
of the loop are capable of producing a strictly linear potential. An effective
theory of these long range fluctuations emerges naturally in the form of a
strongly coupled Z(N) lattice gauge theory. We also point out that dynamical
fermions introduced in this medium undergo chiral symmetry breaking.Comment: 17 pages, LaTex file with 7 eps figures, revised references, minor
comments adde
Path Integral Variational Methods for Strongly Correlated Systems
We introduce a new approach to highly correlated systems which generalizes
the Fermi Hypernetted Chain and Correlated Basis Function techniques. While the
latter approaches can only be applied to systems for which a nonrelativistic
wave function can be defined, the new approach is based on the variation of a
trial hamiltonian within a path integral framework and thus can also be applied
to relativistic and field theoretical problems. We derive a diagrammatic scheme
for the new approach and show how a particular choice of the trial hamiltonian
corresponds exactly to the use of a Jastrow correlated ansatz for the wave
function in the Fermi Hypernetted Chain approach. We show how our new approach
can be used to find upper bounds to ground state energies in systems which the
FHNC cannot handle, including those described by an energy-dependent effective
hamiltonian. We demonstrate our approach by applying it to a quantum field
theoretical system of interacting pions and nucleons.Comment: 35 RevTeX pages, 7 separated ps figures available on reques
Quantum Extremism: Effective Potential and Extremal Paths
The reality and convexity of the effective potential in quantum field
theories has been studied extensively in the context of Euclidean space-time.
It has been shown that canonical and path-integral approaches may yield
different results, thus resolving the `convexity problem'. We discuss the
transferral of these treatments to Minkowskian space-time, which also
necessitates a careful discussion of precisely which field configurations give
the dominant contributions to the path integral. In particular, we study the
effective potential for the N=1 linear sigma model.Comment: 11 pages, 4 figure
A model for string-breaking in QCD
We present a model for string breaking based on the existence of
chromoelectric flux tubes. We predict the form of the long-range potential, and
obtain an estimate of the string breaking length. A prediction is also obtained
for the behaviour with temperature of the string breaking length near the
deconfinement phase transition. We plan to use this model as a guide for a
program of study of string breaking on the lattice.Comment: 7 pages, minor improvements of the text and of the reference lis
Diquarks: condensation without bound states
We employ a bispinor gap equation to study superfluidity at nonzero chemical
potential: mu .neq. 0, in two- and three-colour QCD. The two-colour theory,
QC2D, is an excellent exemplar: the order of truncation of the quark-quark
scattering kernel: K, has no qualitative impact, which allows a straightforward
elucidation of the effects of mu when the coupling is strong. In rainbow-ladder
truncation, diquark bound states appear in the spectrum of the three-colour
theory, a defect that is eliminated by an improvement of K. The corrected gap
equation describes a superfluid phase that is semi-quantitatively similar to
that obtained using the rainbow truncation. A model study suggests that the
width of the superfluid gap and the transition point in QC2D provide reliable
quantitative estimates of those quantities in QCD.Comment: 7 pages, 3 figures, REVTEX, epsfi
Blocking of lattice monopoles from the continuum in hot lattice gluodynamics
The Abelian monopoles in lattice gluodynamics are associated with continuum
monopoles blocked to the lattice. This association allows to predict the
lattice monopole action and density of the (squared) monopole charges from a
continuum monopole model. The method is applied to the static monopoles in high
temperature gluodynamics. We show that the numerical data both for the density
and the action of the lattice monopoles can be described in terms of a Coulomb
gas of Abelian monopoles in the continuum.Comment: 23 pages, 9 EPS figures, LaTeX2e uses JHEP3 class file; replaced to
match published versio