Events

A conference on Algebraic Topology, in memory of Hans-Joachim Baues

This conference is intended to provide an overview of current research in homotopy theory, which has vastly expanded since its roots in the 19th century from the study of topological spaces by algebraic and combinatorial means to other fields of mathematics, including algebraic geometry, differential topology, and mathematical physics.

Please note the VENUE of this talk:
Math Center, Endenicher Allee 60, Room 0.011, Bonn University.
Contact: Stephan Stadler (stadler@mpim-bonn.mpg.de).

The Yamabe invariant is a real-valued diffeomorphism invariant coming from Riemannian geometry. Using Seiberg-Witten theory, LeBrun showed that the sign of the Yamabe invariant of a Kähler surface is determined by its Kodaira dimension. We consider the extent to which this remains true when the Kähler hypothesis is removed. This is joint work with Claude LeBrun.

I will give a brief overview of the development of motivic cohomology, its parallels with singular cohomology and its place in motivic stable homotopy theory. I will then describe some of the recent off-shoots of motivic cohomology: cycles with modulus, Chow-Witt theory, and motivic filtrations on p-adic K-theory, and conclude with some speculations on future developments.

https://icm2022.abstractserver.com/program/#/details/sessions/211

Please note the VENUE of this talk:
Lipschitz-Saal, Endenicher Allee 60, Math. Center, Bonn University.
Contact: Stephan Stadler (stadler@mpim-bonn.mpg.de).

We show that if a 3-manifold admits a metric of finite volume
that is almost hyperbolic in a suitable, then there exists a hyperbolic
metric that is close to the given metric in the $C^{2,\alpha}$-topology.
We then discuss an application of this result to the drilling and filling of
hyperbolic 3-manifolds. The talk is based on joint work with Ursula
Hamenstädt.