![Poisson-Voronoi tessellations and fixed price in higher rank](/media/cache/video_light/uploads/video/Capture%20d%E2%80%99%C3%A9cran%202024-06-13%20%C3%A0%2010.13.20.png)
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Poisson-Voronoi tessellations and fixed price in higher rank
By Amanda Wilkens
![Constructing super-expanders from actions of higher rank lattices](/media/cache/video_light/uploads/video/Capture%20d%E2%80%99%C3%A9cran%202024-06-11%20%C3%A0%2010.04.07.png)
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Constructing super-expanders from actions of higher rank lattices
By Tim de Laat
![Noncommutative rigidity of higher rank lattices - Part 4](/media/cache/video_light/uploads/video/Capture%20d%E2%80%99%C3%A9cran%202024-06-07%20%C3%A0%2011.37.10.png)
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Noncommutative rigidity of higher rank lattices - Part 4
By Cyril Houdayer
Appears in collection : Research School in Discrete Mathematics and Computer Science / École de recherche en mathématiques discrètes et informatique - WEEK 1
In these talks, we will discuss a family of groups called diagram groups, studied extensively by Guba and Sapir and others. These depend on semigroup presentations and turn out to have many good algorithmic properties. The first lecture will be a survey of diagram groups, including several examples and gen-eralizations. The second lecture will take a geometric approach, understanding these groups through median-like geometry.