Related papers: Running Coupling and the Lambda-Parameter from SU(…
We study dynamical symmetry breaking in the Standard Model including the next-to-leading order terms. We introduce at a high, but finite, energy scale Lambda a top quark condensate H={t {bar t}} and derive, using path integral methods, the…
New lattice data for the Pi_u and Sigma_u^- potentials at short distances are presented. We compare perturbation theory to the lower static hybrid potentials and find good agreement at short distances, once the renormalon ambiguities are…
We test a method for computing the static quark-antiquark potential in lattice QCD, which is not based on Wilson loops, but where the trial states are formed by eigenvector components of the covariant lattice Laplace operator. The runtime…
We calculate the third coefficient of the lattice beta function in QCD with Wilson fermions, extending the pure gauge results of Luescher and Weisz; we show how this coefficient modifies the scaling function on the lattice. We also…
We present results for the static inter-quark potential, lightest glueballs, light hadron spectrum and topological susceptibility using a non-perturbatively improved action on a $16^3\times 32$ lattice at a set of values of the bare gauge…
Recently the Yang-Mills gradient flow of pure SU(3) lattice gauge theory has been calculated in the range from $\beta=6/g_0^2=6.3$ to~7.5 (Asakawa et al.), where $g_0^2$ is the bare coupling constant of the SU(3) Wilson action. Estimates of…
We present our latest results for the the complex valued static heavy-quark potential at finite temperature from lattice QCD. The real and imaginary part of the potential are obtained from the position and width of the lowest lying peak in…
We study the running of the L\"uscher-Weisz-Wolff (LWW) coupling constant in the two dimensional O(3) nonlinear $\sigma$ model. To investigate the continuum limit we refine the lattice spacing from the $1\over 16$ value used by LWW up to…
We have applied a new gauge-invariant, noncompact, Monte Carlo method to simulate $U(1)$, $SU(2)$, and $SU(3)$ gauge theories on $8^4$ and $12^4$ lattices. The Creutz ratios of the Wilson loops agree with the exact results for $U(1)$ for…
We give an update on our ongoing investigations of potentials between pairs of static-light mesons in Nf=2 Lattice QCD, in different spin and isospin channels. The question of attraction and repulsion is particularly interesting with…
Using generalized Landau gauge, we study the continuous change of gluon properties from the Landau gauge toward the Coulomb gauge in SU(3) lattice QCD. We investigate "instantaneous interquark potential", which is defined by the spatial…
We consider running coupling constant in holographic model with external magnetic field supported by Einstein-dilaton-three-Maxwell action. We obtain a significant dependence of the running coupling constant $\alpha$ on chemical potential,…
We suggest that Hamiltonian matrix elements between physical states in QCD might be approximated, in Coulomb gauge, by "lattice-improved" tree diagrams; i.e. tree diagram contributions with dressed ghost, transverse gluon, and Coulomb…
Starting from the Schr\"odinger functional, we give a non-perturbative definition of the running coupling constant in QCD. The spatial boundary conditions for the quark fields are chosen such that the massless Dirac operator in the…
We study finite (physical) volume and scaling violation effects of the Landau gauge ghost propagator as well as of the running coupling $\alpha_s(p)$ in the $SU(2)$ lattice gauge theory. We consider lattices with physical linear sizes…
We investigate -- as an alternative to usual Monte Carlo Renormalization Group methods -- the feasibility of extracting QCD beta-functions directly from a lattice analysis of correlations between the action and Wilson loops. We test this…
We compute, via numerical simulations, the non-perturbative Coulomb potential of pure SU(3) gauge theory in Coulomb gauge. We find that that the Coulomb potential scales nicely in accordance with asymptotic freedom, that the Coulomb…
For lattice QCD with two sea quark flavours we compute the static quark antiquark potential V(R) in the regime where string breaking is expected. In order to increase statistics, we make full use of the lattice information by including all…
We compute the $\Pi_u$ and $\Sigma_u^-$ hybrid static potentials in SU(3) lattice gauge theory using four different lattice spacings ranging from $a = 0.040\,\text{fm}$ to $a = 0.093\,\text{fm}$. We provide lattice data points for…
We revisit the static potential for the $Q Q \bar Q \bar Q$ system using SU(3) lattice simulations, studying both the colour singlets groundstate and first excited state. We consider geometries where the two static quarks and the two…