相关论文: Topological structure in the SU(2) vacuum
We study topological properties of SU(3) gauge theory using improved cooling. In the absence of fermions, we measure a topological susceptibility of $(182(8) MeV)^4$ and an instanton size $\sim 0.6$ fm. In the presence of light staggered…
In this article we analyze the vacuum structure of pure SU(2) Yang-Mills using non-perturbative techniques. Monte Carlo simulations are performed for the lattice gauge theory with external sources to obtain the effective potential. Evidence…
We investigate SU(2) gauge fields topology using new approach, which exploits the well known connection between SU(2) gauge theory and quaternionic projective sigma-models and allows to formulate the topological charge density entirely in…
While sign-coherent 4-dimensional structures cannot dominate topological charge fluctuations in the QCD vacuum at all scales due to reflection positivity, it is possible that enhanced coherence exists over extended space-time regions of…
By looking at cooled configurations on the lattice, we study the presence of peaks in the action density, or its electric and magnetic components, in the SU(2) gauge vacuum. The peaks are seen to be of instanton-like nature and their number…
SU(2) lattice gauge theory is investigated where the traces of the Wilson lines at any lattice point and along each direction is constrained to zero. Hence, each of the lattice configurations possesses a vanishing density of heavy (anti-)…
We study the spatial correlator of the topological charge density operator in pure SU(3) gauge theory and in two flavor QCD. We show that the data for distances up to about 1 fm is consistent with a vacuum consisting of individual…
By superposition of regular gauge instantons or merons, ensembles of gauge fields are constructed which describe the confining phase of SU(2) Yang-Mills theory. Various properties of the Wilson loops, the gluon condensate and the…
We calculate the string tension, K, and some of the lightest glueball masses, M, in 3+1 dimensional SU(N) lattice gauge theories for N=2,3,4,5 . From the continuum extrapolation of the lattice values, we find that the mass ratios,…
Using an under-relaxed cooling algorithm we investigated the vacuum in the $2d\ O(3)$ model and $4d$ pure gauge $SU(2)$. We calibrated the amount of cooling performed to have similar physical effect at different lattice spacings.
We study the topological charge fluctuations of an SU(2) lattice gauge theory containing both N_f=2 and 4 flavors of Wilson fermion, at low temperature with non-zero chemical potential $\mu$. The topological susceptibility, chi_T, is used…
We present an update on the study of topological structure of QCD. Issues addressed include a comparison between the plaquette and the geometric methods of calculating the topological density. We show that the improved gauge action based on…
In an attempt to describe the change of topological structure of pure SU(2) gauge theory near deconfinement a renormalization group inspired method is tested. Instead of cooling, blocking and subsequent inverse blocking is applied to Monte…
We exhibit the appropriate variables allowing the plus-minus (Z(2)) `reduction' of the Wilson loop operator which provides a direct measure of the thin, thick and `mixed' Z(2) topological, gauge-invariant vortices in SU(2) LGT. Simulations…
We discuss the physical picture of thick vortices as the mechanism responsible for confinement at arbitrarily weak coupling in SU(2) gauge theory. By introducing appropriate variables on the lattice we distinguish between thin, thick and…
Wilson loops have been measured at strong coupling, $\beta=0.5$, on a $12^4$ lattice in a noncompact simulation of pure SU(2) in which random compact gauge transformations impose a kind of lattice gauge invariance. The Wilson loops suggest…
I show how one can use lattice methods to calculate various continuum properties of SU(N) gauge theories; in part to explore old ideas that N=3 might be close to N=infinity. I describe calculations of the low-lying `glueball' mass spectrum,…
A standard approach to investigate the non-perturbative QCD dynamics is through vacuum models which emphasize the role played by specific gauge field fluctuations, such as instantons, monopoles or vortexes. The effective Hamiltonian…
We study nonequilibrium dynamics of SU(2) lattice gauge theory in Minkowski space-time in a classical-statistical regime, where characteristic gluon occupancies are much larger than unity. In this strongly correlated system far from…
Action and topological charge densities of the Euclidean-space QCD vacuum are visualized in three-dimensional slices of a 24^3 x 36 space-time lattice and an order-a^2 improved 16^3 x 32 lattice. Features include instanton anti-instanton…