Solitons of the Einstein-Yang-Mills Theory

Abstract

Subject of this talk is an overview of results on self-gravitating solitons of the classical Yang-Mills-Higgs theory. One finds essentially two classes of solitons, one of them corresponding to the magnetic monopoles the other one to the sphalerons of flat space. The coupling to the gravitational field leads to new features absent in flat space. These are the gravitational instability of these solitons at the Planck scale and the existence of black holes with `non-abelian hair'' in addition to the regular solutions.