Dynamical quarks effects on the gluon propagation and chiral symmetry restoration

We exploit the recent lattice results for the infrared gluon propagator with light dynamical quarks and solve the gap equation for the quark propagator. Chiral symmetry breaking and confinement (intimately tied with the analytic properties of QCD Schwinger functions) order parameters are then studied.Comment: Contribution to QCD-TNT-III: "From quarks and gluons to hadronic matter: A bridge too far?

Pion's valence-quark GPD and its extension beyond DGLAP region

We briefly report on a recent computation, with the help of a fruitful algebraic model, sketching the pion valence dressed-quark generalized parton distribution and, very preliminary, discuss on a possible avenue to get reliable results in both Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) and Efremov-Radyushkin-Brodsky-Lepage (ERBL) kinematial regions.Comment: 6 pages, 4 figures, contribution to 21st International conference on Few-Body Problem

A brief comment on the similarities of the IR solutions for the ghost propagator DSE in Landau and Coulomb gauges

This brief note is devoted to reconcile the conclusions from a recent analysis of the IR solutions for the ghost propagator Dyson-Schwinger equations in Coulomb gauge with previous studies in Landau gauge.Comment: 4 pages, 1 figur

The scaling infrared DSE solution as a critical end-point for the family of decoupling ones

Both regular (the zero-momentum ghost dressing function not diverging), also named decoupling, and critical (diverging), also named scaling, Yang-Mills propagators solutions can be obtained by analyzing the low-momentum behaviour of the ghost propagator Dyson-Schwinger equation (DSE) in Landau gauge. The asymptotic expression obtained for the regular or decoupling ghost dressing function up to the order ${\cal O}(q^2)$ fits pretty well the low-momentum ghost propagator obtained through the numerical integration of the coupled gluon and ghost DSE in the PT-BFM scheme. Furthermore, when the size of the coupling renormalized at some scale approaches some critical value, the PT-BFM results seems to tend to the the scaling solution as a limiting case.Comment: Presented in QCSHS09; Madrid (Spain), 30 Aug. 201

Comment on "Lattice Gluon and Ghost Propagators, and the Strong Coupling in Pure SU(3)SU(3) Yang-Mills Theory: Finite Lattice Spacing and Volume Effects"

The authors of ref. Phys.Rev. D94 (2016) no.1, 014502 reported about a careful analysis of the impact of lattice artifacts on the $SU(3)$ gauge-field propagators. In particular, they found that the low-momentum behavior of the renormalized propagators depends on the lattice bare coupling and interpreted this fact as the result of it being affected by finite lattice spacing artifacts. We do not share this interpretation and present here a different and more suitable explanation for these results

Are the low-momentum gluon correlations semiclassically determined?

We argue that low-energy gluodynamics can be explained in terms of semi-classical Yang-Mills solutions by demonstrating that lattice gluon correlation functions fit to instanton liquid predictions for low energies and, after cooling, in the whole range.Comment: 4 pages, revtex