2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/56371A lesson for the new millennium from quantum field theory: Not all field-theoretic infinities are bad. Some give rise to finite, symmetry-breaking effects, whose consequences are observed in Nature.13 pages, 1 figure using BoxedEPSF, amsmath macros; contribution to Mathematical Physics 2000, Imperial College Press, London, UK; email to jackiw@ralph2.mit.eduHigh Energy Physics - TheoryHistory and Philosophy of Physicstext