46 research outputs found
Dual Abrikosov Vortices in Confining Theories
The spacial distribution of fields and currents in confining theories can
give direct evidence of dual superconductivity. We would like to discuss the
techniques for finding these properties and calculating the superconductivity
parameters in lattice simulations. We have seen dual Abrikosov vortices
directly in pure U(1) and SU(2) and others have also seen them in SU(3). In the
non-Abelian cases the system appears to be near the borderline between type I
and II. We also discuss the response of the supercurrents to external fields.Comment: 8 pages, Latex , 5 ps figure files attached (figs. 1,3,4,5,6) Talk,
Proceedings at CONFINEMENT95, Osaka, March 199
Confinement studies in lattice QCD
We describe the current search for confinement mechanisms in lattice QCD. We
report on a recent derivation of a lattice Ehrenfest-Maxwell relation for the
Abelian projection of SU(2) lattice gauge theory. This gives a precise lattice
definition of field strength and electric current due to static sources,
charged dynamical fields, gauge fixing and ghosts. In the maximal Abelian gauge
the electric charge is anti-screened analogously to the non-Abelian charge.Comment: Talk given at the Symposium in Honor of Dick Slansky, Los Alamos, May
20-21 1998, to be published in Phys. Rep., Latex 2e uses class file
elsart.cl
Consistent Definitions of Flux and Electric and Magnetic Current in Abelian Projected SU(2) Lattice Gauge Theory
Through the use of a lattice U(1) Ward-Takahashi identity, one can find a
precise definition of flux and electric four-current that does not rely on the
continuum limit. The magnetic four-current defined for example by the
DeGrand-Toussaint construction introduces order a^2 errors in the field
distributions. We advocate using a single definition of flux in order to be
consistent with both the electric and magnetic Maxwell's equations at any
lattice spacing. In a U(1) theory the monopoles are slightly smeared by this
choice, i.e. are no longer associated with a single lattice cube. In Abelian
projected SU(2) the consistent definition suggests further modifications. For
simulations in the scaling window, we do not foresee large changes in the
standard analysis of the dual Abrikosov vortex in the maximal Abelian gauge
because the order a^2 corrections have small fluctuations and tend to cancel
out. However in other gauges, the consequences of our definitions could lead to
large effects which may help in understanding the choice of gauge. We also
examine the effect of truncating all monopoles except for the dominant cluster
on the profile of the dual Abrikosov vortex.Comment: 12 pages, 4 eps figures, Confinement 2003 contributed tal
Vacuum structure of pure gauge theories on the lattice
We present results from simulations on two aspects of quark confinement in
the pure gauge sector. First is the calculation of the profile of the flux tube
connecting a static pair in . By using the Michael sum rules
as a constraint we give evidence that the energy density at the center of the
flux tube goes to a constant as a function of quark separation. Slow variation
of the width and energy density is not ruled out. Secondly in the confined
phase of lattice we calculate the curl of the magnetic monopole current
and show that the dual London equation is satisfied and that the electric
fluxoid is quantized.Comment: 14 pages (no figures, please request preprint), LSU HE NO. 130-199
Model independent approach to studies of the confining dual Abrikosov vortex in SU(2) lattice gauge theory
We address the problem of determining the type I, type II or borderline dual
superconductor behavior in maximal Abelian gauge SU(2) through the study of the
dual Abrikosov vortex. We find that significant electric currents in the
simulation data call into question the use of the dual Ginzburg Landau Higgs
model in interpreting the data. Further, two definitions of the penetration
depth parameter take two different values. The splitting of this parameter into
two is intricately connected to the existence of electric currents. It is
important in our approach that we employ definitions of flux and electric and
magnetic currents that respect Maxwell equations exactly for lattice averages
independent of lattice spacings. Applied to specific Wilson loop sizes, our
conclusions differ from those that use the dual GLH model.Comment: 18 pages, 14 figures, change title, new anaylysis with more figure
Consistency of lattice definitions of U(1) flux in Abelian projected SU(2) gauge theory
We reexamine the dual Abrikosov vortex under the requirement that the lattice
averages of the fields satisfy exact Maxwell equations [ME]. The electric ME
accounts for the total flux and the magnetic ME determines the shape of the
confining string. This leads to unique and consistent definitions of flux and
electric and magnetic currents at finite lattice spacing. The resulting
modification of the standard DeGrand-Toussaint construction gives a magnetic
current comprised of smeared monopoles.Comment: 2 pages, 2 eps figures, Lattice 2003 contributed tal