31 research outputs found
Some properties of renormalons in gauge theories
We find the explicit operatorial form of renormalon-type singularities in
abelian gauge theory. Local operators of dimension six take care of the first
U.V. renormalon, non local operators are needed for I.R. singularities. In the
effective lagrangian constructed with these operators non local imaginary parts
appearing in the usual perturbative expansion at large orders are cancelled.Comment: 17 pages + uuencoded file with 7 figures, REVTeX, IFUP-TH-31-9
Condensation of vortices and disorder parameter in 3d Heisenberg model
The 3d Heisenberg model is studied from a dual point of view. It is shown
that the disordered phase corresponds to condensation of vortices in the
vacuum, and the critical indices are computed from the corresponding disorder
parameter.Comment: LATTICE98(spin
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
Condensation of vortices in the X-Y model in 3d: a disorder parameter
A disorder parameter is constructed which signals the condensation of
vortices. The construction is tested by numerical simulations.Comment: 9 pages, 5 postscript figures, typset using REVTE
A disorder parameter for dual superconductivity in gauge theories
Dual superconductivity in the confining phase of gauge theories is discussed
in terms of a disorder parameter which vanishes in normal phase and is
different from zero in the superconducting phase.Comment: 3 pages, 4 postscript figures, espcrc2, epsfig latex styles,
Contribution to Lat 97 Conference, Edinburg
An Order Parameter Reconciling Abelian and Center Dominance in SU(2) Yang-Mills Theory
We analyze previously proposed order parameters for the confinement -
deconfinement transition in lattice SU(2) Yang-Mills theory, defined as vacuum
expectation value (v.e.v.) of monopole fields in abelian projection gauges. We
show that they exhibit some inconsistency in the treatment of small scales, due
to a violation of Dirac quantization condition for fluxes. We propose a new
order parameter avoiding this inconsistency. It can be interpreted as v.e.v. of
the field of a regular monopole in any abelian projection gauge, but it is
independent of the choice of the abelian projection. Furthermore, being
constructed in terms of surfaces of center vortices, it has also a natural
interpretation in the approach of center dominance.Comment: TeX file, 31 page