Oliver Lindblad Petersen (Hamburg)
I will present a new existence and uniqueness result for wave equations with initial data on compact Cauchy horizons. As an application, we prove that any vacuum spacetime containing a compact Cauchy horizon with constant non-zero surface gravity admits a Killing vector field. This generalizes classical results proven under the assumption of either analyticity of the metric or closedness of the generators. I will also explain the connection to the strong cosmic censorship conjecture in general relativity.