Related papers: A variational approach to the QCD wave functional:…
Perturbation theory is shown to be working in the IR limit of pure SU(3) Yang-Mills theory in Landau gauge by an unconventional setting of the perturbative expansion. A dynamical mass is predicted for the gluon and the lattice data are…
A perturbative regime based on contorsion as a dynamical variable and metric as a (classical) fixed background, is performed in the context of a pure Yang-Mills formulation based on $GL(3,R)$ gauge group. In the massless case we show that…
The low lying spectrum of QCD in the delta-regime is calculated here in chiral perturbation theory up to NNL order. The spectrum has a simple form in terms of the pion decay constant F and a combination of the low energy constants Lambda1…
The Yang-Mills theory with noncommutative fields is constructed following Hamiltonian and lagrangean methods. This modification of the standard Yang-Mills theory shed light on the confinement mechanism viewed as a Lorentz invariance…
Using superfield Dyson-Schwinger equations, we compute the infrared dynamics of the semi-amputated full vertex, corresponding to the effective running gauge coupling, in N-flavour {\mathcal N}=1 supersymmetric QED(3). It is shown that the…
Using the effective potential approach for composite operators, we have formulated a general method of calculation of the truly nonperturbative Yang-Mills vacuum energy density in the covariant gauge QCD ground state quantum models. It is…
An intrinsic measure of the quality of a variational wave function is given by its overlap with the ground state of the system. We derive a general formula to compute this overlap when quantum dynamics in imaginary time is accessible. The…
The response of the QCD vacuum to quark chemical potentials on the order of the pion mass is studied within the context of chiral perturbation theory. For two colour QCD diquark condensation sets in when the baryon chemical potential…
Strongly coupled quantum field theories in $(1+1)$ dimensions are notoriously hard to solve non-perturbatively. Variational methods, despite their success for quantum many-body physics on the lattice, have long lacked a natural ansatz…
Granular systems confined in vertically vibrated shallow horizontal boxes (quasi two-dimensional geometry) present a liquid to solid phase transition when the frequency of the periodic forcing is increased. An effective model, where grains…
In the present work, the Yang-Mills (YM) quantum-wave excitations of the classical homogeneous YM condensate have been studied in quasi-classical approximation. The formalism is initially formulated in the Hamilton gauge and is based upon…
The analysis of (2+1)-dimensional Yang-Mills ($YM_{2+1})$ theory via the use of gauge-invariant matrix variables is reviewed. The vacuum wavefunction, string tension, the propagator mass for gluons, its relation to the magnetic mass for…
We consider here the vacuum structure in QCD with both quark and gluon condensates and a variational ansatz for the ground state. The method is nonperturbative using only equal time algebra for the field operators. We then find that a…
Under assumption of singular behavior of invariant charge alpha_s(q^2) at q^2 sim 0 and of large q^2 behavior, corresponding to the perturbation theory up to four loops, a procedure is considered of smooth matching the beta-function at a…
The nonperturbative vacuum structure which emerges from the zero modes enhancement (ZME) model of the true QCD vacuum, appears to be well suited to describe quark confinement, dynamical chiral symmetry breaking (DCSB), current-effective…
The Debye mass m_D is computed nonperturbatively in the deconfined phase of QCD, where chromomagnetic confinement is known to be present. The latter defines m_D to be m_D=c_D\sqrt{\sigma_s}, where c_D \cong 2.06 and \sigma_s=\sigma_s(T) is…
A general method for treating non-Gaussian wave functionals in quantum field theory is presented and applied to the Hamiltonian approach to Yang-Mills theory in Coulomb gauge in order to include a three-gluon kernel in the exponential of…
We investigate dynamical mass generation in pseudo-Proca quantum electrodynamics (PPQED) using Schwinger--Dyson equations in rainbow-quenched and unquenched approximations. The (3+1)D gauge-field mass $m$, fine-structure constant $\alpha$,…
We investigate the dependence of the QCD vacuum structure on the $\theta$-angle and quark mass, using the Di-Vecchia--Veneziano model. Although the Di-Vecchia--Veneziano model is a chiral effective model, it contains the topological…
A local and renormalizable version of a modified PQCD introduced in previous works is presented. The construction indicates that it could be equivalent to massless QCD. The case in which only quark condensate effects are retained is…