Related papers: Instantons and $<A^2>$ Condensate
A Langevin equation for the complex amplitude of a single-mode Bose-Einstein condensate is derived. The equation is first formulated phenomenologically, defining three transport parameters. It is then also derived microscopically.…
The gluon propagator in Landau gauge is calculated in quenched QCD on a large (32^3X64) lattice at beta=6.0. In order to assess finite volume and finite lattice spacing artefacts, we also calculate the propagator on a smaller volume for two…
In dimension $D\leq 2$ the low temperature behavior of systems enjoying a continuous symmetry is dominated by super-instantons: classical configurations of arbitrarily low energy. Perturbation theory in the background of a super-instanton…
Canonical instanton theory is a widespread approach to describe the dynamics of chemical reactions in low temperature environments when tunneling effects become dominant. It is a semiclassical theory which requires locating classical…
We reinvestigate the problem of Gribov ambiguities within the Landau (or Lorentz) gauge for the ghost and gluon propagators in pure SU(2) lattice gauge theory. We make use of the full symmetry group of the action taking into account {\it…
The mode structure of a Bose-Einstein condensate non-adiabatically loaded into a one-dimensional optical lattice is studied by analyzing the visibility of the interference pattern as well as the radial profile of the condensate after a…
In a recent work we described the form taken by the Minkowski-space gluon propagator in the presence of an A^2 condensate. This condensate has been seen to play an important role in calculations which make use of the operator product…
The interplay between the finite volume and finite lattice spacing is investigated using lattice QCD simulations to compute the Landau gauge gluon propagator at zero temperature. Comparing several ensembles with different lattice spacings…
In SU(2) lattice gauge theory, a new self-restricted cooling procedure is developed to uncover the gauge invariant vortex vacuum texture. The emerging vortex vacuum structure amounts to the full string tension and gives rise to a mass…
We discuss instanton operators in five-dimensional gauge theories. These are defined as disorder operators which create a non-vanishing second Chern class on a four-sphere surrounding their insertion point. As such they may be thought of as…
It is shown that gauge invariance of the operator \int dx tr(A_{\mu}^{2}-\frac{2}{g \xi} x^{\nu} \theta_{\mu\nu} A^{\mu}) in noncommutative gauge theory does not lead to gauge independence of its vacuum condensate. Generalized Ward…
In recent years, the Gribov-Zwanziger action was refined by taking into account certain dimension 2 condensates. In this fashion, one succeeded in bringing the gluon and the ghost propagator obtained from the GZ model in qualitative and…
A number of observables are constructed which can give useful information on instanton ensembles.The basic properties used are : (1) Instantons are SU(2) configurations ,(2)They are self-dual or antiself-dual.
We study bubbling phenomena of anti-self-dual instantons on $\H^2\times\S$, where $\S$ is a closed Riemann surface. The restriction of the instanton to each boundary slice $\{z\}\times\S$, $z\in\pd\H^2$ is required to lie in a Lagrangian…
Lattice measurements of the Pisa group (A.Di Giacomo et al., hep-lat/9603018) are analyzed numerically and parameters of correlation functions are extracted from the data - both below and above deconfinement temperature Tc. Gluon condensate…
We address the problem of calculating the correlation functions in a system of one-dimensional hard-core anyons that can be experimentally realized in optical lattices. Using the summation of form factors we have obtained Fredholm…
We investigate a phenomenon of creation of excitations in the homogenous Bose-Einstein condensate due to an impurity moving with a constant velocity. A simple model is considered to take into account dynamical effects due to motions of the…
We study damping of a dipole oscillation in a Bose-Condensed gas in a combined cigar-shaped harmonic trap and one-dimensional (1D) optical lattice potential at finite temperatures. In order to include the effect of thermal excitations in…
An analysis of the temperature dependence of the leading contributions to the gluon condensate for SU(N) lattice gauge theory is presented using the data from recent Monte Carlo simulations. The gluon condensate is calculated directly from…
Motivated by axion-like inflation and its warm embedding within the Standard Model, we study the early stages of the energy transfer between an axion condensate and an SU(2) gauge ensemble, by employing non-linear classical real-time…