Aspects of the Gribov-Zwanziger framework

Understand

The existence of gauge (Gribov) copies disturbs the usual Faddeev-Popov 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 Gribov-Zwanziger action), implementing the restriction of the path integration to the so-called Gribov region, which is free of a subset of gauge copies, but not of all copies.