Embedded Spheres and 4–manifolds with Spin Coverings

  title={Embedded Spheres and 4–manifolds with Spin Coverings},
  author={C. Bohr},
A strategy for constructing an embedded sphere in a 4–manifold realizing a given homology class which has been successfully applied in the past is to represent the class as a first step stably by an embedded sphere, i.e. after adding products of 2–spheres, and to move that sphere back into the original manifold. In this paper, we study under what conditions the first step of this approach can be carried out if the 4–manifold at hand is not simply connected. One of our main results is that there… CONTINUE READING