10.04.2018 um 16:15 Uhr in 69/125:
Arun Kumar (Universität Osnabrück)
We will construct the Grassmannian and the Quaternionic Grassmannian Varieties and see how are they are related to Algebraic and Hermitian K-theory respectively.
24.04.2018 um 16:15 Uhr in 69/125:
Holger Brenner (Universität Osnabrück)
Asymptotic properties of differential operators on a singularity
For a local algebra R over a field, we study the decomposition of the module of principal parts. A free summand of the nth module of principal parts is essentially the same as a differential operator E of order ≤ n with the property that the differential equation E(f) =1 has a solution. The asymptotic behavior of the seize of the free part gives a measure for the singularity represented by R. We compute this invariant for invariant rings, monoid rings, determinantal rings and compare it with the F-signature, which is an invariant in positive characteristic defined by looking at the asymptotic decomposition of the Frobenius. This is joint work with Jack Jeffries and Luis Nuñez Betancourt.