ABSTRACT
As happens with the fermions, there is also no theoretical constraint on the number of Higgs elds. So, why should there be only one Higgs particle? is is clearly the simplest solution, and thus it has been built into the standard model. But it is certainly not compulsory. Indeed, many believe that having only one Higgs would be highly unnatural. As a result, theories with several Higgs elds have been studied almost since the beginning of the standard model.
