Vanishing geodesic distance on spaces of submanifolds and diffeomorphisms

Peter Michor
(University of Vienna)

Abstract: The L2-metric or Fubini-Study metric on the non-linear Grassmannian of all submanifolds of type M in a Riemannian manifold (N,g) 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 L2-metric. A special case is Burgers' equation.