## Welcome to SPP 2026

This is the platform of a coordinated research programme in mathematics, funded by the German Research Foundation (DFG). It comprises 80 research projects in the fields of differential geometry, geometric topology, and global analysis. More than 80 researchers from doctoral to professorial level and based at more than 20 German and Swiss universities are represented in this programme.

### Appeal from Ukrainian mathematicians

The whole world witnessed how on February 24, the President of Russia Putin started a military invasion of Ukraine, which is a blatant act of…

## Next Activities

## Latest publications

#### Quasi-morphisms on surface diffeomorphism groups

Jonathan Bowden, Sebastian Hensel and Richard Webb

We show that the identity component of the group of diffeomorphisms of a closed oriented surface of positive genus admits many unbounded…

#### Local Flexibility for Open Partial Differential Relations

Christian Bär, Bernhard Hanke

We show that local deformations, near closed subsets, of solutions to open partial differential relations can be extended to global deformations,…

#### Bounded subgroups of relatively finitely presented groups

Eduard Schesler

Given a finitely generated group $G$ that is relatively finitely presented with respect to a collection of peripheral subgroups, we prove that every…

#### Stability of the Non-Symmetric Space E7/PSO(8)

Paul Schwahn, Uwe Semmelmann, Gregor Weingart

We prove that the normal metric on the homogeneous space E7/PSO(8) is stable

with respect to the Einstein-Hilbert action, thereby exhibiting the…

## Latest Blog posts

**Finite subgroups of homeomorphism groups**If \(M\) is a compact topological manifold, can one say something about its group of homeomorphisms \(\mathrm{Homeo}(M)\)? Of course one can, there is quite a lot to say about it, and there is also quite a lot which we still don’t know. Today I want to mention the following recent result by Csikós-Pyber-Szabó (arXiv:2204.13375): Let … Continue reading "Finite subgroups of homeomorphism groups"

**A quantitative coarse obstruction to psc-metrics**Recently, Guo and Yu pushed the following result to the arXiv (math.KT/2203.15003): For any \(R > 0\) and positive integer \(m\), there exists a constant \(k(R,m)\) such that the following holds. If \((M,g)\) is a Riemannian spin manifold that admits a uniformly bounded, good open cover with Lebesgue number \(R\) and \(R\)-multiplicity \(m\), then \[\inf_{x \in M} \kappa_g(x) \le … Continue reading "A quantitative coarse obstruction to psc-metrics"