Top-level heading

Hermitian-Yang-Mills approach to the conjecture of Griffiths on the positivity of ample vector bundles

Given a vector bundle of arbitrary rank with ample determinant line bundle on a projective manifold, we propose a new elliptic system of differential equations of Hermitian-Yang-Mills type for the cur...

A Bonnet-Myers Theorem from a spectral assumption

We obtain a finiteness result for the fundamental group of a closed Riemannian manifold $(M^n,g)$ under the assumption that the Schrödinger operator $\Delta_g+(n-2)/\rho$ is positive (where at $x\in M...

On a relative version of Serre's notion of G-complete reducibility

We first review some basic results related to Serre's notion of G-complete reducibility for a reductive algebraic group G. We then discuss a relative variant of this concept where we let K be a reduct...

Projective flatness over klt spaces and uniformisation of varieties with nef anti-canonical divisor

I will discuss a criterion for the projectivisation of a reflexive sheaf on a klt space to be induced by a projective representation of the fundamental group of the smooth locus. This criterion is the...

Rigid compact complex manifolds: recent results, questions and conjectures

The aim of this talk is to give an update on recent achievements and developments on rigid compact complex manifolds. I will start introducing different notions of rigidity and explaining the relation...

Scalar positive immersions

As shown by Gromov-Lawson and Stolz the only obstruction to the existence of positive scalar curvature metrics on closed simply connected manifolds in dimensions at least five appears on spin manifold...

Embeddings of smooth affine varieties into algebraic groups

This is joint work with Peter Feller. In any category there are the following fundamental problems concerning embeddings from an object Z into another object X: 1. (Existence) Does there exist an embe...

The geometry of polynomial functors

A polynomial functor P is a functor from the category of finite-dimensional vector spaces to itself such that for every U,V the map Hom(U,V) -> Hom(P(U),P(V)) is polynomial. In characteristic zero,...

Birational geometry of Calabi-Yau pairs and 3-dimensional Cremona transformations

ecently, Oguiso addressed the following question, attributed to Gizatullin: “Which automorphisms of a smooth quartic K3 surface $D\subset\mathbb{P}^3$ are induced by Cremona transformations of the amb...