Groups and Geometry


Welcome to the common homepage of the research groups of Barbara Baumeister, Kai-Uwe Bux and Christopher Voll. Here you can find information about the members of our group as well as joint activites, conferences and workshops we organise and courses that we offer.

We are supported by and members of:


Name Research interests Homepage
Working group Baumeister
PD Dr. habil. Barbara Baumeister Finite group theory, permutation groups. Reflection groups, Coxeter groups and generalisations. Artin groups. More
Dr. Georges Neaime Coxeter Groups, Artin Groups, Garside structures, Complex Reflection Groups, Complex Braid Groups, Hecke Algebras. More
Working group Bux
Prof. Dr. Kai-Uwe Bux Geometric group theory, finiteness properties of groups, arithmetic groups, Thompson's groups. More
Dr. Xiaolei Wu Geometric group theory, finiteness properties of groups, manifold topology, algebraic K-theory of group rings. More
Jonas Flechsig Geometric group theory, orbifold braid groups, arc matching complexes. More
Working group Voll
Prof. Dr. Christopher Voll Asymptotic group theory, algebraic combinatorics, enumerative problems. More
Dr. Seungjai Lee Zeta functions of groups, rings and other algebraic objects, finite group theory, algebraic combinatorics. More
Dr. Josh Maglione Algebraic combinatorics, asymptotic group theory, computational algebra. More
Dr. Viola Siconolfi Algebraic combinatorics, Coxeter theory, hyperplane arrangements. More
Dr. Mima Stanojkovski $p$-groups, automorphisms, isomorphism problems. More
Elena Tielker Representation theory of finite \( p \)-groups, zeta functions of groups. More
Marlies Vantomme Zeta functions. More

Former members

  • Prof. Dr. Stefan Witzel
  • Dr. Sophiane Yahiatène
  • Prof. Dr. Dawid Kielak
  • Dr. Eduard Schesler
  • Christoph Hilmes
  • Dr. Benjamin Brück
  • Dr. Alastair Litterick
  • Dr. Yuri Santos Rego
  • Dr. Paula Lins



Title Lecturer Link
Winter semester 2021/2022
Masterseminar AlgebraChristopher VollMore
Masterseminar KryptographieBarbara BaumeisterMore
Mathematik für Naturwissenschaften I Christopher VollMore
Operations ResearchBarbara BaumeisterMore
Orientierende PraxisstudienBarbara BaumeisterMore
Proseminar CoxetergruppenJosh MaglioneMore
Proseminar Konvexe GeometrieElena TielkerMore
StochastikKai-Uwe BuxMore

Title Lecturer Link
Summer semester 2021
Asymptotische GruppentheorieChristopher VollMore
Diskrete Mathematik III: Kryptographie mit nicht-abelschen GruppenBarbara BaumeisterMore
Einführung in die LogikKai-Uwe BuxMore
Lie Algebras and Lie GroupsChristopher VollMore
Mathematik für Chemie IIChristopher VollMore
Optimization and DynamicsViola SiconolfiMore
Winter semester 2020/2021
Commutative Algebra and Algebraic GeometryChristopher VollMore
Discrete Mathematics II: CryptographyBarbara BaumeisterMore
Mathematics I for chemistsChristopher VollMore
Optimization for Quatitative EconomicsSeungjai LeeMore
Summer semester 2020
Algebraic Number TheoryChristopher VollMore
Discrete Mathematics I: Coding TheoryBarbara BaumeisterMore
Knot TheoryDawid KielakMore
Mathematics for Natural Science IIChristopher VollMore
Optimization and DynamicsJoshua MaglioneMore
Proseminar: Groups and SymmetriesXiaolei WuMore
Stochastics IIKai-Uwe BuxMore
Winter semester 2019/2020
3-ManifoldsDawid KielakMore
Mathematics for Natural Science IChristopher VollMore
Operations ResearchBarbara BaumeisterMore
Proseminar: Graph TheoryJoshua MaglioneMore
Proseminar: Groups and GraphsChristoph Hilmes, Jonas FlechsigMore
StochasticsKai-Uwe BuxMore
Summer semester 2019
\(L^2 \)-InvariantsDawid KielakMore
Algebra IIMima StanojkovskiMore
Analysis IIKai-Uwe BuxMore
Elementary number theoryBarbara BaumeisterMore
Monster & Co: The finite simple groupsBarbara BaumeisterMore
Winter semester 2018/2019
Algebra IChristopher VollMore
Analysis IKai-Uwe BuxMore
Data and randomnessBarbara BaumeisterMore
Masterseminar on non-crossing partitions, Coxeter- and Artin groupsBarbara Baumeister, Georges NeaimeMore


Seminar Link
Winter semester 2021/2022
Oberseminar Groups and GeometryMore
Reading group on Affine BuildingsMore
Reading group on Sigma invariantsMore

Seminar Link
Summer semester 2021
Oberseminar Groups and GeometryMore
Reading group about big Mapping Class GroupsMore
Reading group on tropical geometryMore
Winter semester 2020/2021
Oberseminar Groups and GeometryMore
Reading group about Thompson's groupsMore
Reading group in asymptotic group theoryMore
Summer semester 2020
Oberseminar Groups and GeometryMore
Reading Group: Asymptotic Group TheoryMore
Winter semester 2019/2020
Oberseminar Groups and GeometryMore
Reading Group: Asymptotic Group TheoryMore
Tuesday GGTMore
Summer semester 2019
Friday GGTMore
Oberseminar Groups and GeometryMore
Reading group Asymptotic Group TheoryMore
The Geometry of Coxeter and Artin GroupsMore
Winter semester 2018/2019
Oberseminar Groups and GeometryMore
Reading group Asymptotic Group TheoryMore


Sep 24th - Sep 26th, 2019
Outer Space in Bielefeld

The Faculty of Mathematics will host this conference about outer space, groups of (outer) automorphisms of free groups and related topics.

Mar 30th - Apr 03rd, 2020
Topological and Homological Methods in Group Theory

The third instalment of the THGT series.

Aug 30th - Sep 04th, 2021
The dual approach to Coxeter and Artin groups; Garside theory and applications

The event is a summer school organised by Barbara Baumeister, Georges Neaime, and Sarah Rees.