Welcome to SPP 2026
This is the platform of a coordinated research programme in mathematics, funded by the German Research Foundation (DFG). It comprises 33 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.
Next Activities
Latest publications
S-arithmetic spinor groups with the same finite quotients and distinct ℓ²-cohomology
Holger Kammeyer, Roman Sauer
In this note we refine examples by Aka from arithmetic to S-arithmetic groups to show that the vanishing of the i-th ℓ²-Betti number is not a...
Profinite commensurability of S-arithmetic groups
Holger Kammeyer
Given an S-arithmetic group, we ask how much information on the ambient algebraic group, number field of definition, and set of places S is encoded in...
Wave and Dirac equations on manifolds
Lars Andersson, Christian Bär
We review some recent results on geometric equations on Lorentzian manifolds such as the wave and Dirac equations. This includes well-posedness and...
Convex projective surfaces with compatible Weyl connection are hyperbolic
Thomas Mettler, Gabriel P. Paternain
We show that a properly convex projective structure p on a closed oriented surface of negative Euler characteristic arises from a Weyl connection if...