Appendix E: Non-abelian Higgs Mechanism
261
Theorem E.1 improves the perturbative analysis since it does not rely on a semiclassical mean field ansatz nor on the summability of the perturbative series; moreover, the order parameter is not restricted to be a point-like field. Furthermore, the
exclusion of physical Goldstone bosons associated with the breaking of the global
gauge group G provides a sharper argument with respect to the mere non-applicability
of the Goldstone theorem in physical gauge by lack of local order parameters, which
may invalidate the local generation of the symmetry.
261
Theorem E.1 improves the perturbative analysis since it does not rely on a semiclassical mean field ansatz nor on the summability of the perturbative series; moreover, the order parameter is not restricted to be a point-like field. Furthermore, the
exclusion of physical Goldstone bosons associated with the breaking of the global
gauge group G provides a sharper argument with respect to the mere non-applicability
of the Goldstone theorem in physical gauge by lack of local order parameters, which
may invalidate the local generation of the symmetry.