Spontaneous compactification of space in an Einstein-Yang-Mills-Higgs model

It is shown that classical solutions of an Einstein-Yang-Mills-Higgs system exist such that space-time is the direct product of the Minkowski space by a compact internal space of constant curvature. The symmetry group of the internal space determines the masses in such a way that singlets have the lowest energy, non-singlet states having huge masses. (Auth.)