Algebra/Topology seminar

Daniel Kasprowski (Universität Bonn)

Title: CP^2 stable diffeomorphism of 4-manifolds

Abstract: Two 4-manifolds are said to be CP^2 stably diffeomorphic if after connected sum with arbitrarily many copies of the complex projective plane, they become diffeomorphic. 

For many fundamental groups the classification of 4-manifolds up to CP^2 stable diffeomorphism is determined by the homotopy 2-type. This is joint work with Mark Powell and Peter Teichner.