Infrared finite effective charge of QCD

dc.creatorAguilar, A. C.
dc.creatorBinosi, D.
dc.creatorPapavassiliou, J.
dc.date2008-10-14
dc.date.accessioned2026-07-07T13:03:05Z
dc.date.available2026-07-07T13:03:05Z
dc.descriptionWe show that the gauge invariant treatment of the Schwinger-Dyson equations of QCD leads to an infrared finite gluon propagator, signaling the dynamical generation of an effective gluon mass, and a non-enhanced ghost propagator, in qualitative agreement with recent lattice data. The truncation scheme employed is based on the synergy between the pinch technique and the background field method. One of its most powerful features is that the transversality of the gluon self-energy is manifestly preserved, exactly as dictated by the BRST symmetry of the theory. We then explain, for the first time in the literature, how to construct non-perturbatively a renormalization group invariant quantity out of the conventional gluon propagator. This newly constructed quantity serves as the natural starting point for defining a non-perturbative effective charge for QCD, which constitutes, in all respects, the generalization in a non-Abelian context of the universal QED effective charge. This strong effective charge displays asymptotic freedom in the ultraviolet, while in the low-energy regime it freezes at a finite value, giving rise to an infrared fixed point for QCD. Some possible pitfalls related to the extraction of such an effective charge from infrared finite gluon propagators, such as those found on the lattice, are briefly discussed.
dc.descriptionInvited talk given at LIGHT CONE 2008 Relativistic Nuclear and Particle Physics, July 7-11 2008 Mulhouse, France
dc.identifierhttps://arxiv.org/abs/0810.2333
dc.identifierhttp://arxiv.org/abs/0810.2333
dc.identifierPoS LC2008:050,2008
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/226675
dc.subjectHigh Energy Physics - Phenomenology
dc.titleInfrared finite effective charge of QCD
dc.typetext

Files

Collections