2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/56249The local action of an SU(2) gauge theory in general covariant Abelian gauges and the associated equivariant BRST symmetry that guarantees the perturbative renormalizability of the model are given. I show that a global SL(2,R) symmetry of the model is spontaneously broken by ghost-antighost condensation at arbitrarily small coupling and leads to propagators that are finite at Euclidean momenta for all elementary fields except the Abelian ``photon''. The Goldstone states form a BRST-quartet. The mechanism eliminates the non-abelian infrared divergences in the perturbative high-temperature expansion of the free energy.4 pages. Much improved argumentation based on a certain (spontaneously broken) SL(2,R) symmetryHigh Energy Physics - TheoryHigh Energy Physics - LatticeHigh Energy Physics - Phenomenologytext