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Tuesday, January 21, 2020

**Abstract:** Artin groups emerged from the study of braid groups and complex hyperplane arrangements, and they are connected to Coxeter groups, 3-manifold groups, buildings and many others. Artin groups have very simple presentation, yet rather mysterious geometry with many basic questions widely open. I will present a way of understanding certain Artin groups and Garside groups by building geometric models on which they act. These geometric models are non-positively curved in an appropriate sense, and such curvature structure yields several new results on the algorithmic, topological and geometric aspects of these groups. No previous knowledge on Artin groups or Garside groups is required. This is joint work with D. Osajda.

Wednesday, January 22, 2020

Thursday, January 23, 2020

Friday, January 24, 2020

Monday, January 27, 2020

Tuesday, March 24, 2020

Tuesday, March 31, 2020

Thursday, April 16, 2020

Thursday, April 30, 2020