Fabien Morel (München)
Cohomological invariants and H_0 of classifying spaces
Abstract: Given a smooth affine algebraic k-group G we define the universal cohomological invariant for G-torsors. For G connected semi-simple, we explain how the conjectural injectivity of this universal invariant is related to the conjectures of Serre on H^1(k;G). We give examples.
