Previous Conferences & Workshops

The minimal log discrepancy is a measure of singularities of pairs. While akin to the log canonical threshold, it turns out to be much more difficult to study, with many questions still open. I will discuss a question about the boundedness of...

We discuss developments in motivic homotopy theory over the last ten years, including structural aspects, the role of Postnikov towers, oriented theories and quadratic forms.

We provide a simple proof of the Rota--Heron--Welsh conjecture for matroids realizable as c-arrangements in the sense of Goresky--MacPherson: we prove that the coefficients of the characteristic polynomial of the associated matroids form log-concave...

Given a Legendrian knot, I will construct a category of constructible sheaves, invariant under Legendrian isotopy up to equivalence. The constructble sheaves live on the front plane and are stratified by the front diagram of the Legendrian knot. I...

An important theme in homogenous dynamics is that two parameter diagonalizable actions have much more rigidity than one parameter actions. One manifestation of this rigidity is rigidity of joinings of such actions. Joinings are an important concept...

Given a $k$-edge-connected graph $G = (V,E)$, a spanning tree $T$ is $\alpha$-thin w.r.t. $G$, if for any $S \subset V$, $|T(S,V - S)| \leq \alpha.|E(S,V - S)|$. The thin tree conjecture asserts that for a sufficiently large $k$ (independent of size...

This will be an elementary/intuitive introduction to the $\pi_1$ of smooth algebraic varieties in $\mathbf A^1$-homotopy theory (over algebraically closed fields of char 0). We will give some flavor on the $\pi_0$ and $\pi_1$. Most of the...

In my talk I will report on recent work with Hansjörg Geiges about a strong connection between the topology of a contact manifold and the existence of contractible periodic Reeb orbits. Namely, if the contact manifold appears as non-trivial contact...

The Moebius function plays a central role in number theory; both the prime number theorem and the Riemann Hypothesis are naturally formulated in terms of the amount of cancellations one gets when summing the Moebius function. In recent joint work...