In 1966 V. Arnold showed how solutions of the Euler equations of
hydrodynamics can be viewed as geodesics in the group of
volume-preserving diffeomorphisms. This provided a motivation to
study the geometry of this group equipped with the $L^2$...
This talk will discuss joint work with Michael Handel concerning
the dynamic structure of symplectic diffeomorphisms of the
two-sphere. The intended application is the study of groups of
"fully supported" diffeomorphisms (e.g. analytic) and the...
