Date(s) : 19/01/2015 iCal
14 h 00 min - 15 h 00 min
In this talk I will discuss a coupled system of partial differential equations for a pair of functions on the 2-dimensional sphere. I will comment on the physical interpretation of the solutions, as cosmic strings in the Abelian Higgs model coupled with gravity (a hypothetical structure predicted by many models in cosmology). By dimensional reduction of a system of equations in four dimensions (the Coupled Kahler-Yang-Mills equations), we will see that the original system fits into a symplectic reduction framework. This will be applied to recover a qualitative version of an existence result by Yisong Yang for the « cosmic string equations ». Based on joint work with Luis Alvarez-Consul and Oscar Garcia-Prada.