Hilbert spaces can affinely spot amenability
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Event details
Date | 21.05.2015 |
Hour | 13:00 › 14:00 |
Speaker | Maxime Gheysens (École polytechnique fédérale de Lausanne) |
Location | |
Category | Conferences - Seminars |
Ergodic and Geometric Group Theory seminar
Day proved in the early sixties a nice geometric fixed-point property characterising amenability. We show that such a characterisation already holds in the Hilbert world --- hence in particular Hilbert spaces are not better-behaved than a general locally convex space from this viewpoint. Along the way, we introduce a variant of the classical induction for non-isometric representations and investigate techniques allowing to transfer results about free groups to general non-amenable groups. Joint work with Nicolas Monod.
Day proved in the early sixties a nice geometric fixed-point property characterising amenability. We show that such a characterisation already holds in the Hilbert world --- hence in particular Hilbert spaces are not better-behaved than a general locally convex space from this viewpoint. Along the way, we introduce a variant of the classical induction for non-isometric representations and investigate techniques allowing to transfer results about free groups to general non-amenable groups. Joint work with Nicolas Monod.
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Practical information
- Informed public
- Free
Organizer
- Nicolas Monod
Contact
- Maxime Gheysens