Geometry, Topology and Dynamics Seminar
Egor Shelukhin
Institute for Advanced Study, Princeton
The diameter of the $L^1$-metric on the group of area-preserving diffeomorphisms of $S^2$.
Abstract: We use a geometric idea to give an analytic estimate for the word-length in the pure braid group
of $S^2$. This yields that the $L^1$-norm (and hence each $L^p$-norm, including $L^2$)
on the area-preserving diffeomorphism group of $S^2$ is unbounded.
This solves an open question arising from the work of Shnirelman and Eliashberg-Ratiu.
Joint work in progress with Michael Brandenbursky.
Monday November 30, 2015 at 3:00 PM in SEO 636