Non-abelian symmetric critical gravitating vortices on a sphere

Abstract: We produce examples of solutions to the non-abelian gravitating vortex equations, which are a dimensional reduction of the K\"aher-Yang-Mills- Higgs equations. These are equations for a K\"ahler metric and a metric on a vector bundle. We consider a symmetric situation on a sphere with a relationship between the parameters involved (criticality), and perform a non-trivial reduction of the problem to a system of ordinary differential equations on the real line with complicated boundary conditions at infinity. This system involves a parameter whose dependence on the volume of the K\"ahler metric is non-explicit. We prove existence to this system using the method of continuity. We then prove that the parameter can be varied to make sure that all possible admissible volumes are attained.