Magnetic monopoles in supersymmetric grand unification

It is shown that in supersymmetric grand unified theories, the monopole ground state necessarily carries a nonzero color charge and in general has a fractional electric charge. This is the manifestation of fermion fractionization which occurs because of the coupling of the monopoles with the heavy fermion sector, whose existence is required by supersymmetry. The fate of the monopole ground state is discussed. (orig.)