Around a big mapping class group
Duration: 45 mins 9 secs
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About this item
| Description: |
Bavard, J
Monday 19th June 2017 - 14:30 to 15:30 |
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| Created: | 2017-07-17 16:41 |
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| Collection: | Non-Positive Curvature Group Actions and Cohomology |
| Publisher: | Isaac Newton Institute |
| Copyright: | Bavard, J |
| Language: | eng (English) |
| Distribution: |
World
(downloadable)
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| Explicit content: | No |
| Aspect Ratio: | 16:9 |
| Screencast: | No |
| Bumper: | UCS Default |
| Trailer: | UCS Default |
| Abstract: | Co-author: Alden Walker (Center for Communications Research, La Jolla)
The mapping class group of the plane minus a Cantor set naturally appears in many dynamical contexts, including group actions on surfaces, the study of groups of homeomorphisms on a Cantor set, and complex dynamics. In this talk, I will present the 'ray graph', which is a Gromov-hyperbolic graph on which this big mapping class group acts by isometries (it is an equivalent of the curve graph for this surface of infinite topological type). If time allows, I will explain how we can use this action to construct non trivial quasimorphisms on this group, although it is not acylindrically hyperbolic. This might involve joint work with Alden Walker. |
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