In fairness, I think there is a way that quantised charge could, in an implausible theory, arise directly from topological concerns. [sketch of crank theory] You'd start with a Yang-Mills gauge theory set up so that after symmetry breaking you have a U(1) with a large coupling constant g >> 1, but in which there were no particles which actually coupled to the U(1) gauge field. The theory has 't Hooft-Polyakov monopoles, and you find that their magnetic charges are determined by the winding number of maps from the sphere at infinity to U(1). You now have single type of source of electromagnetic fields (namely, magnetic monopoles) with a small coupling constant ~1/g << 1. Switch your "magnetic" and "electric" terminology, and you're done. [/sketch of crank theory] It is somewhat pointless, probably, as the theory we started with could (as you mentioned) give you charge quantisation anyway, in a more direct fashion. Please Register or Log in to view the hidden image!