Real loci

Duistermaat first introduced and studied real loci.  A real locus is the fixed point set of an anti-symplectic involution on a symplectic manifold.  The most familiar examples are the real points of a complex projective variety.  Many results of symplectic geometry apply to these Lagrangian submanifolds.  I worked on several projects confirming this idea.

I am currently working on two projects in this area.  With Reyer Sjamaar, I am working to understand the real loci of symplectic reductions by non-abelian groups.  With Jean-Claude Hausmann, I am trying to make a more systematic study of real loci in a context somewhere between the very algebraic approach in our paper with Volker Puppe and the very symplectic approach in other works on real loci.