Nontopological magnetic monopoles and new magnetically charged black holes.

The existence of nonsingular classical magnetic monopole solutions is usually understood in terms of topologically nontrivial Higgs field configurations. We show that finite energy magnetic monopole solutions also exist within a class of purely Abelian gauge theories containing charged vector mesons, even though the possibility of nontrivial topology does not even arise. provided that certain relationships among the parameters of the theory are satisfied. These solutions are singular if these relationships do not hold, but even then become meaningful once the theory is coupled to gravity, for they then give rise to an interesting new class of magnetically charged black holes with hair. It was shown by ’t Hooft and Polyakov [1] that classical finite energy magnetic monopole solutions occur in certain spontaneously broken non-Abelian gauge theories. The existence of these solutions is often understood in terms of topologically nontrivial Higgs field configurations. In this letter we show that finite energy magnetic monopoles can also be obtained in a class of purely Abelian theories in which such topological consideratations do not even arise, provided that certain relationships among the parameters of the theory are satisfied. These solutions are singular if these relationships do not hold, but even then become meaningful This work was supported in part by the National Science Foundation Presidential Young Investigator Program, the Alfred P. Sloan Foundation, and the US Department of Energy