Speaker
Description
Correlation functions are the building blocks in quantum field theory, from which any physical observable can be (in principle) calculated. In a theory with gauge symmetry, however, correlation functions are not physical objects, being dependent on the particular gauge fixing prescription. In this work a novel approach is presented, which allows to separately calculate, within the class of linear covariant gauges, the gauge dependent part of an arbitrary correlation function. This framework, which consists in introducing a Stueckelberg field and other auxiliary fields in the theory, allows to generalize the Landau-Khalatnikov-Fradkin transformations, known in quantum electrodynamics, to the case of non abelian gauge symmetry. Consistency checks have been carried out by calculating the gauge dependent parts of the gluon propagator at the one loop level and of the quark propagator at the two loops level.
