arXiv subjects

V. Gogokhia

Publications and source records attributed to V. Gogokhia.

21 records · Page 2Linked to original sources

arXiv2006

Energy from the nonperturbative QCD vacuum

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 (the Bag constant apart from the sign, by definition). It is the main dynamical characteristic of the QCD ground state. We define it as an integration of the truly nonperturbative effective charge over the nonperturbative region (soft momentum region). It is free of all types of the perturbative contributions, by construction. For the considered truly nonperturbative effective charge it is finite, negative and it has no imaginary part (stable vacuum), as well as it is a manifestly gauge-invariant, i.e., not explicitly depending on the gauge-fixing parameter. A nontrivial minimization procedure makes it possible to determine the Bag constant as a function either of the mass gap, which is responsible for the large-scale structure of the true QCD vacuum, or of the effective scale, which separates the nonperturbative region from the perturbative one. We have also argued that the Bag constant is a quant of energy density which can be released from the QCD vacuum, which, in its turn, is considering as an infinite and permanent reservoir of energy.

hep-ph↗

arXiv2006

A temporary violation of color gauge invariance as a source of the Jaffe-Witten mass gap in QCD

We propose to realize a mass gap in QCD by not imposing the transversality condition on the full gluon self-energy, while preserving the color gauge invariance condition for the full gluon propagator. This is justified by the nonlinear and nonperturbative dynamics of QCD. None of physical observables/processes in low-energy QCD will be directly affected by such a temporary violation of color gauge invariance/symmetry. No truncations/approximations and no special gauge choice are made for the regularized skeleton loop integrals, contributing to the full gluon self-energy, which enters the Schwinger-Dyson equation for the full gluon propagator. In order to make the existence of a mass gap perfectly clear the corresponding subtraction procedure is introduced. All this allows one to establish the general structure of the full gluon propagator and the corresponding gluon Schwinger-Dyson equation in the presence of a mass gap. It is mainly generated by the nonlinear interaction of massless gluon modes.The physical meaning of the mass gap is to be responsible for the large-scale (low-energy/momentum), i.e., nonperturbative structure of the true QCD vacuum. In the presence of a mass gap two different types of solutions for the full gluon propagator are possible. The massive solution leads to an effective gluon mass, which explicitly depends on the gauge-fixing parameter. This solution becomes smooth at small gluon momentum in the Landau gauge. The general iteration solution is always severely singular at small gluon momentum, i.e., the gluons remain massless, and this does not depend on the gauge choice. We also formulate a general method how to restore the transversality of the gluon propagator relevant for nonperturbative QCD.

hep-ph↗

arXiv2006

How to demonstrate a possible existence of a mass gap in QCD

We propose to realize a mass gap in QCD by not imposing the transversality condition on the full gluon self-energy, while preserving the color gauge invariance condition for the full gluon propagator. This is justified by the nonlinear and nonperturbative dynamics of QCD. None of physical observables/processes in low-energy QCD will be directly affected by such a temporary violation of color gauge invariance/symmetry. No truncations/approximations and no special gauge are made for the regularized skeleton loop integrals, contributing to the full gluon self-energy, which enters the Schwinger-Dyson equation for the full gluon propagator. In order to make the existence of a mass gap perfectly clear the corresponding subtraction procedure is introduced. All this allows one to establish the general structure of the full gluon propagator and the gluon Schwinger-Dyson equation in the presence of a mass gap. It is mainly generated by the nonlinear interaction of massless gluon modes. The physical meaning of the mass gap is to be responsible for the large-scale (low-energy/momentum), i.e., nonperturbative structure of the true QCD vacuum. In the presence of a mass gap two different types of solutions for the full gluon propagator are possible. The massive solution leads to an affective gluon mass, which depends on the gauge-fixing parameter explicitly. This solution becomes smooth at small gluon momentum in the Landau gauge. The general iteration solution is always severely singular at small gluon momentum, i.e., the gluons remain massless, and this does not depend on the gauge choice.

hep-th↗