Boundaries, stability, and singularities in general relativity
– A meeting celebrating Helmut Friedrich’s 80th birthday

Several important developments have taken place in mathematical general relativity in recent years, and the goal of the workshop is to gather leading researchers in these and related fields to provide an opportunity for discussions, exchange of ideas, and new collaborations.

One development concerns the fundamental problem of proving stability of the Kerr and Kerr de Sitter spacetimes. In the last twenty years, several groups have worked intensively on the resolution of this problem, and in the last years, they have finally succeeded. In addition, several results concerning stable big bang formation have been obtained.  In particular, a result providing a general condition (without reference to a background solution) guaranteeing big bang formation with curvature blow up appeared last year. Further, there have been dramatic new developments on initial boundary value problems, including   our understanding of the dynamics of anti-de Sitter spacetime. Last but not least, gluing techniques of initial data sets have been developed, which have proved to be  very useful in constructing spacetimes with interesting global properties.

Helmut Friedrich has made several seminal contributions to the field and we take this opportunity to honor his work on the occasion on his 80th birthday. Indeed, Friedrich proved the first global non-linear stability result (de Sitter space), he has made fundamental contributions to our understanding of the asymptotic structure of solutions and he is one of the pioneers when it comes to studying the very subtle initial-boundary value problem for Einstein’s equations, including well-posedness in the anti-de Sitter setting.