## PIMS Marsden Memorial Lecture: Richard Schoen

- Date: 07/19/2016

Banff International Research Station (BIRS), Banff

The global study of the space of solutions of the Einstein constraint equations goes back to work of Jerry Marsden and co-workers in the early 1970s. Since that time the subject has evolved in interesting ways. First it has been possible to localize the deformation theory in certain cases to deform solutions inside a chosen region without changing them outside. A second issue which arises in the deformation theory is a derivative loss problem which occurs when one attempts to place a manifold structure on the constraint space of solutions with a finite degree of differentiability. In this general lecture we will give an overview of these issues and developments.

A video of this event is available on the BIRS event webpage

The Marsden Memorial Lecture Series is dedicated to the memory of Jerrold E Marsden (1942-2010), a world-renowned Canadian applied mathematician. Marsden was the Carl F Braun Professor of Control and Dynamical Systems at Caltech, and prior to that he was at the University of California (Berkeley) for many years. He did extensive research in the areas of geometric mechanics, dynamical systems and control theory. He was one of the original founders in the early 1970’s of reduction theory for mechanical systems with symmetry, which remains an active and much studied area of research today.