Vanishing geodesic distance on spaces of submanifolds and diffeomorphisms
arXiv:math/0409303
Abstract
The -metric or Fubini-Study metric on the non-linear Grassmannian of all submanifolds of type in a Riemannian manifold induces geodesic distance 0. We discuss another metric which involves the mean curvature and shows that its geodesic distance is a good topological metric. The vanishing phenomenon for the geodesic distance holds also for all diffeomorphism groups for the -metric.
26 pages, LATEX, final version