Non-Abelian monopole and dyon solutions in a modified Einstein-Yang-Mills-Higgs system

We study a modified Yang-Mills-Higgs system coupled to Einstein gravity. The modification of the Einstein-Hilbert action involves the direct coupling of the Higgs field to the scalar curvature. In this modified system we are able to write a Bogomol’nyi type condition in curved space and demonstrate that the positive static energy functional is bounded from below. We then investigate non-Abelian spherically symmetric static solutions in a similar fashion to the ’t Hooft–Polyakov monopole. After reviewing previously studied monopole solutions of this type, we extend the formalism to include electric charge and we present dyon solutions.