Séminare Bourbaki: Convex-cocompactness in higher rank

Today, there was the Séminaire Bourbaki, which takes place every four months in Paris. The list of the talks can be found here. Interesting from the point of view „Geometry at Infinity“ was especially the talk of Olivier Guichard regarding work of Kapovich-Leeb-Porti and Labourie on convex-cocompact groups in higher rank symmetric spaces: Another talk … Continue reading "Séminare Bourbaki: Convex-cocompactness in higher rank"

What’s new on the ArXiv: Zimmer’s conjecture for actions of SL(m,Z)

Zimmer’s conjecture aims to extend Margulis’ superrigidity theorem to a nonlinear setting. Except for actions on the circle there has not been much progress in the last 35 years. A new preprint of Brown-Fisher-Hurtado and its predecessor are now settling the conjecture for finite index subgroups of \(SL(n,{\mathbb Z})\) and cocompact lattices in \(SL(n,{\mathbb R})\). … Continue reading "What’s new on the ArXiv: Zimmer’s conjecture for actions of SL(m,Z)"

What’s new on the ArXiv: Quasiconvexity and Dehn filling

One of the most important theorems in 3-manifolds topology is Agol’s Theorem asserting that every closed 3-manifold is virtually fibered and in particular virtually Haken. Agol proved this theorem in early 2012 for closed hyperbolic manifolds. The general (closed) case reduces to hyperbolic manifolds via geometrization. The case of cusped hyperbolic manifolds was left open … Continue reading "What’s new on the ArXiv: Quasiconvexity and Dehn filling"