Volumes of balls in large Riemannian manifolds


Larry Guth

Stanford

May 8, 2007


Abstract:  In the 80's, Gromov made several conjectures about the volumes of balls in Riemannian manifolds.  The spirit of these conjectures is that if a Riemannian manifold is "large", then it should contain a unit ball whose volume is not too small.  For example, if you take the standard metric on the n-sphere and increase it pointwise to form a new metric, then Gromov's conjecture implies that the new metric should contain a unit ball whose volume is bounded below by a constant c(n).  I proved some of the conjectures, including this one.  I will explain the conjectures and give some context, and then I will try to say something about the proof.