Former projects:

• Master's thesis: Homomorphisms of generalized hexagons
   Universität Würzburg, 1998
  advisors: Theo Grundhöfer, Linus Kramer
• PhD thesis: On graphs, geometries, and groups of Lie type
  TU Eindhoven, 2002
  advisors: Arjeh Cohen, Sergey Shpectorov, Hans Cuypers
• Habilitation thesis: Phan Theory
  TU Darmstadt, 2004
  referees: Karl-Hermann Neeb, Linus Kramer, Arjeh Cohen, Richard Lyons
• Finite Phan theory: Survey
  Classical groups: A_n, B_n: Part 1, Part 2, C_n, D_n
  joint with Curt Bennett, Corneliu Hoffman, Sergey Shpectorov assisted by Max Horn, Werner Nickel
  Exceptional groups: E_6, E_7, E_8, F_4 joint with Alice Devillers, Bernhard Mühlherr, Stefan Witzel
• Covering theory of intransitive geometries: without fusion, with fusion
   joint with Max Horn, Antonio Pasini, Hendrik Van Maldeghem
• DFG project GR 2077/4: Centralizers of fundamental subgroups of Chevalley groups

Former PhD students:

• Kristina Altmann: Centralisers of fundamental subgroups
  Defense on 6 February 2007
• Max Horn: Involutions of Kac-Moody groups
  Defense on 17 April 2009
• Stefan Witzel: Finiteness properties of Chevalley groups over the ring of (Laurent) polynomials over a finite field
  Defense on 2 February 2011 
• Andreas Mars: The geometry and topology of Kac-Moody groups
  Defense on 3 February 2011

Former undergraduate students:

Diplom

• Kristina Altmann (2003): The geometry of non degenerate subspaces of complex orthogonal space
  published as On the geometry on the nondegenerate subspaces of orthogonal space
  
• Max Horn (2005): Amalgams of unitary groups in Sp(2n,q)
  published as The complete Phan-type theorem for Sp(2n,q)
  
• Frauke Harrach (2006): Linearity of braid groups
• Sascha Sieverding (2006): Historische und mathematische Aspekte zur Lokalisation von Nullstellen
  (Historical and mathematical aspects of the location of zeros of complex polynomials)
• Karsten Hayn (2007): Properties of K-Theory related functors over skew fields
• Andreas Mars (2007): Unitary forms of locally finite Kac-Moody groups
  published as Isomorphisms of unitary forms of Kac-Moody groups over finite fields
  
• Katja Möser (2007): Endomorphismen von verallgemeinerten Vielecken
  (Endomorphisms of generalized polygons)
• Stefan Witzel (2008): The affine structure of cubical complexes
• Armin Straub (2008): Local recognition of reflection graphs on Coxeter groups
  published as The local recognition of reflection graphs of spherical Coxeter groups
  
• Jens Fischer (2009): Zentrale Erweiterungen von Kac-Moody-Gruppen
  (Central extensions of Kac-Moody groups)
• Oliver Schmitt (2010): Der Satz von Nagao
  (Nagao's theorem)
• Dennis Völker (2010): Erzeuger und Relation von Quantentori
  (Generators and relations of quantum tori)

Bachelor

• Susanne Schimpf (2008): Homology of the complex of non-degenerate subspaces of unitary space
• Hugo Fernandez (2010): Classification of finite Coxeter groups
• Tobias Hufler (2010): Rationale Adèle
  (Rational adèles)
• Claudia Sowadzki (2011): Die Modulgruppe
  (The modular group)
• Sven Schäfer (2011): Der Minkowskische Gitterpunktsatz
  (Minkowski's convex body theorem)
• Julius Grüning (2012): Riemannflächen (Riemann surfaces)
• Anne Hukelmann (2012): Präsentierung der ganzzahligen speziellen linearen Gruppe (Presentation of the special linear group over the integers)
  

MSci

• David Hume (2009): Extensions of Borovoi's theorem