conference title: Arithmetic groups and 3-manifolds

Arithmetic groups and 3-manifolds

A conference at University of Hagen, Germany

March 23rd-27th, 2020

Arithmetic groups provide a fruitful link between various areas, such as geometry, topology, representation theory and number theory. Methods from geometry and topology hinge on the fact that arithmetic groups are lattices in Lie groups, whereas the theory of automorphic forms establishes a connection to representation theory and number theory. This interplay is especially intriguing in the setting of hyperbolic 3-manifolds. Indeed many conjectures in 3-manifold theory tend to be much more accessible for hyperbolic 3-manifolds whose fundamental groups are arithmetic, and conversely such manifolds provide the simplest set-up in which some of the most exciting new phenomena in the Langlands program can be studied. This conference will bring together researchers with various backgrounds around links between number theory and 3-manifolds. Central topics of the conference are the cohomology of arithmetic groups, the relation between torsion and L²-torsion, profinite invariants of 3-manifolds, and number theoretic ramifications.
Date and place


  • Mikhail Belolipetsky (Rio de Janeiro)
  • Martin Bridson (Oxford)
  • Nathan Dunfield (Urbana-Champaign)
  • Stefan Friedl (Regensburg)
  • Andrei Jaikin (Madrid)
  • Aditi Kar (London)
  • Dawid Kielak (Bielefeld)
  • Jasmin Matz (Essen)
  • Anke Pohl (Bremen)
  • Jean Raimbault (Toulouse)
  • Lola Thompson (Oberlin)
  • Tyakal Venkataramana (Mumbai)
  • Gareth Wilkes (Cambridge)

Scientific advisory board

  • Alan Reid (Houston)
  • Thomas Schick (Göttingen)
  • Joachim Schwermer (Bonn)


  • Holger Kammeyer (Karlsruhe)
  • Steffen Kionke (Hagen)
  • Haluk Şengün (Sheffield)


The conference will take place from March 23rd at 11:00 am to March 27th at 13:00 pm. A detailed schedule will follow soon.


To sign up as a participant of the conference, please visit the registration form available from the DFG priority program "Geometry at Infinity". We have limited funding available to support early career scientists. Please indicate on the registration form whether you would like to apply for financial support and use the message field to briefly describe your career status and your motivation to take part in the event.


For any inquiry, please contact one of the organizers:
Holger Kammeyer
Steffen Kionke
Haluk Şengün