Algebra/Topology seminar

Martin Speirs (Copenhagen)

Title: K-theory of coordinate axes in characteristic p

Abstract: I will talk about work in progress on computing the algebraic K-theory of the singular affine curve given by the coordinate axes in affine space over F_p-algebras. In the analogous case over the rational numbers the K-theory groups were computed by Geller, Reid and Weibel. Hesselholt then carried out the computation over F_p-algebras in the 2-dimensional case. I will sketch the computation for arbitrary dimensions, using the cyclotomic trace map from K-theory to topological cyclic homology. The cyclotomic trace amazingly allows one to give completely explicit calculations.