Abstract:Many moduli spaces can be described as ball quotients. Examples include the Deligne-Mostow varieties, moduli of cubic surfaces and certain moduli spaces of lattice-polarized $K3$ surfaces. Here I will discuss the geometry of some of these examples, including their topology and different (partial) resolutions. I will also comment on the relationship with the Minimal Model Program. This...
Abstract:The Hitchin morphism is a map from the moduli space of Higgs bundles to the Hitchin base, which is generally not surjective when the dimension of the variety is greater than one. Chen-Ngo introduced the concept of the spectral base, which is a closed subscheme of the Hitchin base. They conjectured that the Hitchin morphism is surjective to the spectral base and also proved that the su...