Differential Geometry Working Seminar

Spiro Karigiannis, Department of Pure Mathematics, University of Waterloo

“The linear algebra of 2-forms in 4-dimensions”

I will present some important facts about the linear algebra of 2-forms in 4 dimensions, which everyone should know. We start with classical results about self-dual and anti-self dual 2-forms, and then proceed to discuss "hypersymplectic" structures in 4d à la Donaldson. Then we put all this on an oriented Riemannian 4-manifold.