Prof. Dr. Ruth Charney (Brandeis University, USA)Colloquium: Exploring the Mysteries of Artin groups
Wednesday, 25.09.2024 14:30 im Raum M3
Coxeter groups arise in many areas of mathematics including topology, algebraic geometry, representation theory, and combinatorics. They are much studied and generally well-understood. Closely related to Coxeter groups are a class of groups known as Artin groups. The best known examples of these groups are the braid groups. While easy to define, Artin groups are much more mysterious than Coxeter groups with many key properties unknown and basic questions unanswered. In this talk, I will introduce Artin groups, discuss some of the open problems, and survey some recent work, using both combinatorial and geometric methods, to approach these problems.
Angelegt am 17.09.2024 von Anke Pietsch
Geändert am 18.09.2024 von Anke Pietsch
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17. John von Neumann Lecture: Prof. Dr. Lisa Sauermann (Universität Bonn): On three-term progression-free sets and related questions in additive combinatorics
Thursday, 17.10.2024 16:15 im Raum M4
Given some large positive integer N, what is the largest possible size of a subset of {1,...,N} which does not contain a three-term arithmetic progression (i.e. without three distinct elements x,y,z satisfying x+z=2y)? Similarly, given a prime p and a large positive integer n, what is the largest possible size of a subset of the vector space F_p^n which does not contain a three-term arithmetic progression (i..e without three distinct vectors x,y,z satisfying x+z=2y)? These are long-standing problems in additive combinatorics. This talk will explain the known bounds for these problems, give an overview of some of the proof techniques, and discuss additional applications of these techniques to other additive combinatorics problems.
Angelegt am 21.08.2024 von Claudia Lückert
Geändert am 04.09.2024 von Carolin Gietz
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