56 research outputs found

### BPS and non-BPS Domain Walls in Supersymmetric QCD with SU(3) Gauge Group

We study the spectrum of the domain walls interpolating between different
chirally asymmetric vacua in supersymmetric QCD with the SU(3) gauge group and
including 2 pairs of chiral matter multiplets in fundamental and
anti-fundamental representations. For small enough masses m < m* = .286... (in
the units of \Lambda), there are two different domain wall solutions which are
BPS-saturated and two types of ``wallsome sphalerons''. At m = m*, two BPS
branches join together and, in the interval m* < m < m** = 3.704..., BPS
equations have no solutions but there are solutions to the equations of motion
describing a non-BPS domain wall and a sphaleron. For m > m**, there are no
solutions whatsoever.Comment: 10 pages LaTeX, 5 postscript figure

### Upper bound on the cutoff in lattice Electroweak theory

We investigate numerically lattice Weinberg - Salam model without fermions
for realistic values of the fine structure constant and the Weinberg angle. We
also analyze the data of the previous numerical investigations of lattice
Electroweak theory. We have found that moving along the line of constant
physics when the lattice spacing $a$ is decreased, one should leave the
physical Higgs phase of the theory at a certain value of $a$. Our estimate of
the minimal value of the lattice spacing is $a_c = [430\pm 40 {\rm Gev}]^{-1}$.Comment: Latex, 21 pages, 3 figures, to appear in JHE

### Central Dominance and the Confinement Mechanism in Gluodynamics

New topological objects, which we call center monopoles, naturally arise in
the Maximal Center Projection of SU(3) gluodynamics. The condensate of the
center monopoles is the order parameter of the theory.Comment: 4 pages revtex, 3 figure

### Strings and Aharonov-Bohm Effect in Abelian Higgs Model

We investigate numerically the properties of the Abrikosov-Nielsen-Olesen
strings in 4D abelian Higgs model. The fractal dimension D_f of the vortex
strings was found to be large in the Coulomb phase and it is close to 2 in the
Higgs phase. We also show that the Wilson loop for non-integer charges is
correlated with the linking number of the vortex string world sheets and the
test particle world trajectory. We find that this topological (Aharonov-Bohm)
interaction gives the main contribution to the Wilson loop quantum average for
non-integer test charges in the vicinity of the Coulomb-Higgs phase transition.Comment: 8 pages, LaTeX, 5 EPS-figures, uses epsf.st

### Abelian Monopoles and Action Density in SU(2) Gluodynamics on the Lattice

We show that the extended Abelian magnetic monopoles in the Maximal Abelian
projection of lattice SU(2) gluodynamics are locally correlated with the
magnetic and the electric parts of the SU(2) action density. These correlations
are observed in the confined and in the deconfined phases.Comment: 11 pages, LaTeX2e, 5 figures, uses epsf.sty; revision: Introduction
is extended and a few references are adde

### A hidden symmetry in the Standard Model

We found an additional symmetry hidden in the fermion and Higgs sectors of
the Standard Model. It is connected to the centers of the SU(3) and SU(2)
subgroups of the gauge group. A lattice regularization of the whole Standard
Model is constructed that possesses this symmetry.Comment: 6 pages, no figures. Shortened versio

### Aharonov-Bohm effect, Center Monopoles and Center Vortices in SU(2) Lattice Gluodynamics

SU(2) gluodynamics is investigated numerically and analytically in the
(Indirect) Maximal Center gauge at finite temperature. The center vortices are
shown to be condensed in the confinement phase and dilute in the deconfinement
phase. A new physical object, center monopole, is constructed. We show that the
center monopole condensate is the order parameter of deconfinement phase
transition. The linking of the vortex worldsheets and quark trajectories is
identified with the Aharonov-Bohm interaction in an effective Abelian Higgs
theory. We conclude that the confinement in the Maximal Center gauge can be
explained by a new mechanism called "the real superconductor mechanism".Comment: LATTICE98(confine), 3 pages, LaTeX, 2 eps figures, uses espcrc2.st

### Evidence for the reality of singular configurations in SU(2) gauge theory

We consider the SU(2) lattice gauge model and investigate numerically the
continuum limit of the simple center vortices which are singular configurations
of the gauge fields. We found that the vortices remain alive in the continuum
theory. Also we investigate the Creutz ratio and found that for all $\beta$ it
vanishes for those field configurations which do not contain the simple center
vortices inside the considered Wilson loop. It leads us to the conclusion that
these singular field configurations play a real role in the continuum theory.Comment: 10 pages LaTeX, 2 .eps figure

### SU(2) lattice gauge theory at non-zero temperature with fixed holonomy boundary condition

We study SU(2) lattice gauge theory at $T>0$ in a finite box with fixed
holonomy value at the spatial boundary. We search for (approximate) classical
solutions of the lattice field equations and find in particular the dissociated
calorons recently discussed by van Baal and collaborators.Comment: Talk at Lattice 2000, Bangalore; 4 pages, 4 figures, LaTe

### Calorons and BPS monopoles with non-trivial holonomy in the confinement phase of SU(2) gluodynamics

With the help of the cooling method applied to SU(2) lattice gauge theory at
non-zero $T \le T_c$ we present numerical evidence for the existence of
superpositions of Kraan-van Baal caloron (or BPS monopole pair) solutions with
non-trivial holonomy, which might constitute an important contribution to the
semi-classical approximation of the partition function.Comment: 3 pages, 6 figures, contribution to Lattice2002(topology

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