2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/44886It is possible to find different sets of local coordinates in the field space of Yang-Mills theories which implement Gauss' law manifestly for physical states. The singular points of the transformations to these gauge-invariant coordinates induce energy barriers in the Hamiltonian much like angular momentum in quantum mechanics, and these formulations suggest a vacuum state functional qualitatively different from the perturbative one. Lecture given at the XIII Particles and Nuclei International Conference, Perugia, Italy, June 28 - July 2, 1993.4 pages, TeX, UB-ECM-PF 93/16High Energy Physics - Phenomenologytext