Bonn 2010 – wissenschaftliches Programm
T 13.8: Vortrag
Donnerstag, 18. März 2010, 18:40–18:55, HG XVI
Stabilizing topologically nontrivial spacetimes with an SO(3)-Skyrme field — •Markus Schwarz — Institut für Theoretische Physik, Universität Karlsruhe, KIT
One possible result of a theory of quantum gravity is that spacetime might have a "foamy" and topologically nontrivial structure on small scales. Since there is no complete theory of quantum gravity yet, we investigate classical models with nontrivial spacetime topology. One of these is an SO(3)-Skyrme model interacting with gravity on spacetimes of topology R× SO(3).
This particular class of spacetimes can be realized by cutting a ball of radius b out of Minkowski spacetime and identifying antipodal points. To prevent a spacetime with such a defect from collapsing, an SO(3)-valued scalar field together with a Skyrme Lagrangian is added.
The resulting Einstein-SO(3)-Skyrme model admits classical solutions where the SO(3)-Skyrme field has integer winding number. For odd winding numbers there exists a nonzero radius b that minimizes the mass of the spacetime. This means that we have found a potentially stable spacetime with nontrivial topology. We briefly discuss similarities to and differences from the Einstein-SU(2)-Skyrme model.