2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/56027We look at and compare two different methods developed earlier for inducing gauge invariances in systems with second class constraints. These two methods, the Batalin-Fradkin method and the Gauge Unfixing method, are applied to a number of systems. We find that the extra field introduced in the Batalin-Fradkin method can actually be found in the original phase space itself.Latex file, 12 pages, Contribution to ``Photon and Poincare Group'', edited by Valeri Dvoeglazov for Nova Science Publishers, New YorkHigh Energy Physics - Theorytext