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Tag Archives: hyperbolic groups
Random groups contain surface subgroups
A few weeks ago, Ian Agol, Vlad Markovic, Ursula Hamenstadt and I organized a “hot topics” workshop at MSRI with the title Surface subgroups and cube complexes. The conference was pretty well attended, and (I believe) was a big success; … Continue reading
Agol’s Virtual Haken Theorem (part 2): AgolGrovesManning strike back
Today Jason Manning gave a talk on a vital ingredient in the proof of Agol’s theorem, which is a result in geometric group theory. The theorem is a joint project of AgolGrovesManning, and generalizes some earlier work they did a … Continue reading
Polygonal words
Last Friday, Henry Wilton gave a talk at Caltech about his recent joint work with Sanghyun Kim on polygonal words in free groups. Their work is motivated by the following wellknown question of Gromov: Question(Gromov): Let be a oneended wordhyperbolic group. … Continue reading
Posted in Groups, Surfaces
Tagged double of free group, ends, Henry Wilton, hyperbolic groups, roundoff trick, Sanghyun Kim, scl, Stallings theorem on ends, surface subgroup
6 Comments
Combable functions
The purpose of this post is to discuss my recent paper with Koji Fujiwara, which will shortly appear in Ergodic Theory and Dynamical Systems, both for its own sake, and in order to motivate some open questions that I find … Continue reading
Groups with free subgroups
More ambitious than simply showing that a group is infinite is to show that it contains an infinite subgroup of a certain kind. One of the most important kinds of subgroup to study are free groups. Hence, one is interested … Continue reading
Posted in Groups
Tagged amenable groups, free groups, hyperbolic groups, laws, pingpong, Thompson's group, Tits alternative, von Neumann conjecture
3 Comments
five week plan
As an experiment, I plan to spend the next five weeks documenting my current research on this blog. This research comprises several related projects, but most are concerned in one way or another with the general program of studying the … Continue reading
Posted in Overview
Tagged Gromov's question, hyperbolic groups, scl, stable commutator length, surface groups
4 Comments