Thursday, March 27, at 3:30 pm in HH312.

Abstract: It is an ongoing search for exotic manifolds which are homeomorphic to a sum of complex projective planes (or the sum with only oppositely oriented projective planes). Relaxing this condition, a definite manifold is one with an intersection form at least isomorphic to that of such a space. The door into the study of definite exotica was first opened thanks to the discovery of exotic definite 4-manifolds with non-trivial fundamental group by Levine, Lidman and Piccirillo. We will discuss one of the more recent recipes, as well as the ingredients that can be used for building such exotica. This is based on joint work with Patrick Naylor and B. Doug Park.