Aspects of the GribovZwanziger framework
Abstract
The existence of gauge (Gribov) copies disturbs the usual FaddeevPopov quantization procedure in the Landau gauge. It is a very hard job to treat these in the continuum, even in a partial manner. A decent way to do so was worked out by Gribov, and later on by Zwanziger. The final point was a renormalizable action (the GribovZwanziger action), implementing the restriction of the path integration to the socalled Gribov region, which is free of a subset of gauge copies, but not of all copies. Till recently, everybody agreed upon the fact that the restriction to the Gribov region implied a infrared enhanced ghost, and vanishing zero momentum gluon propagator. We discuss how the GribovZwanziger action naturally leads to the existence of vacuum condensates of dimension two. As it is very common, such condensates can seriously alter the dynamics. In particular, the GribovZwanziger condensates give rise to a gluon propagator with a finite but nonvanishing zero momentum limit, and reconstitute a nonenhanced ghost. We call this the refined GribovZwanziger framework. The predictions are in qualitative agreement with most recent lattice simulations, and certain solutions of the SchwingerDyson equations. A crucial feature of the GribovZwanziger framework is the soft (controllable) breaking of the BRST symmetry. We also point out that imposing the KugoOjima confinement criterion on the FaddeevPopov theory as a boundary condition from the beginning leads to the same partition function as of GribovZwanziger, with associated BRST symmetry breaking. This clouds the interpretation of the KugoOjima criterion in se.
 Publication:

International Workshop on QCD Green's Functions, Confinement and Phenomenology
 Pub Date:
 2009
 DOI:
 10.22323/1.087.0012
 arXiv:
 arXiv:0911.0082
 Bibcode:
 2009iwqg.confE..12D
 Keywords:

 High Energy Physics  Theory
 EPrint:
 12 pages, proceeding for the International Workshop on QCD Green's Functions, Confinement, and Phenomenology (QCDTNT09)