Spherically symmetric monopole solutions
Classical gauge theories are studied for spherically symmetric monopole solutions. The Higgs field is taken in the adjoint representation and in the limit of vanishing self-interaction. The equations of motion can be represented by a Lax pair. Using techniques from group representation theory, explicit solutions are obtained in the case of the principal embedding of the symmetry group SU(2) in the bigger gauge group. The parameters of the solutions can be chosen to give finite fields everywhere, and the large r behaviour of the Higgs field, which determines the symmetry breaking, is discussed. Some low rank groups are studied as examples. Next, some properties of the non-principal SU(2) embeddings and their classification are discussed. These are then used to obtain more solutions, but the problem has not been solved for the most general case.