Towards Skyrmion Stars: Large Baryon Number Configurations in the Einstein-Skyrme Model

Abstract

The large baryon number sector of the Einstein-Skyrme model has been investigated, as a possible model for baryon stars. Self-gravitating hedgehog skyrmions have been studied previously and the existence of stable sol і tonic stars excluded due to energy considerations. However, in this thesis it is demonstrated that by generating self gravitating skyrnions using harmonic maps, one can achieve multi-baryon bound states. The question of the spatial symmetry of such configurations is discussed and it is argued that, although low baryon number solutions have various symmetries, approximate spherical symmetry is recoverered in the case of very large baryon numbers. Plausible structures are obtained, that possess baryon numbers typical to neutron stars and one concludes that indeed, the Einstein-Skyrme system can be used a toy model for baryon stars.