April 15, 2024 to July 5, 2024
Europe/Paris timezone

Thematic trimester programme with short courses, seminars and workshops

April 15 to July 5, 2024 at the Institut Henri Poincaré, Paris


Financial support request is complete

Presentation of the trimester

This term focuses on rigidity of group actions with some focus on issues that arise out of Zimmer's groundbreaking work in the 1980's. Areas of interest range from local and global rigidity of group actions to special rigidity phenomena in small dimensions to symmetry groups of geometric structures to measure rigidity results for quite general group actions with hyperbolicity.
This broad area has seen a very large number of dramatic breakthroughs in recent years. The goal of the term is to bring together experts and people in adjacent areas to share ideas and techniques and to foster additional breakthroughs. There will also be a significant component of the term dedicated to introducing younger participants to the broad area.

Introductory School:

April 15 to 19, 2024: Rigidity, Dynamics and Geometric Structures, held at CIRM, Marseille


April 29 to Saturday, May 4, 2024: Low Dimensional Actions (IHP, Paris)

May 27 to 31, 2024: Group Actions with Hyperbolicity and Measure Rigidity (IHP, Paris)

June 10 to 14, 2024: Actions of Large Groups, Geometric Structures, and the Zimmer Program (IHP, Paris)


Mini-courses will be held in amphitheater Darboux in IHP. The standard format will be three 2h long lectures during one week for each mini-course. More details will be updated soon.

  • Bertrand Deroin (Université de Cergy & CNRS): Week of May 6
  • Thang Nguyen (Florida State University): Week of May 13
  • Romain Dujardin (Sorbonne Université): Week of May 20
  • Cyril Houdayer (ENS Paris): Week of June 3
  • Karin Melnick (University of Luxembourg): Week of June 3
  • Kurt Vinhage (University of Utah): Week of June 17

Preliminary list of participants

  • Yves Benoist (Université Paris-Saclay & CNRS) 
  • Aaron Brown (Northwestern University)
  • Serge Cantat (Université de Rennes I & CNRS)
  • Sylvain Crovisier (Université Paris-Saclay & CNRS)
  • Danijela Damjanovic (KTH Royal Institute of Technology)
  • Bertrand Deroin (Université de Cergy & CNRS)
  • Romain Dujardin (Sorbonne Université)
  • Simion Filip (University of Chicago)
  • David Fisher (Rice University)
  • * Alex Furman (University of Illinois at Chicago)
  • * Étienne Ghys (ENS Lyon & CNRS & Académie des Sciences)
  • Cyril Houdayer (Université Paris-Saclay)
  • Homin Lee (Northwestern University)
  • Sebastian Hurtado (Yale University)
  • Kathryn Mann (Cornell University)
  • Karin Melnick (University of Maryland)
  • Dave Morris (University of Lethbridge)
  • * Amos Nevo (Technion - Israel Institute of Technology)
  • Thang Nguyen (Florida State University)
  • Vincent Pecastaing (Université Côte d'Azur)
  • Beatrice Pozzetti (Heidelberg University)
  • * Jean-François Quint (Université Bordeaux I & CNRS)
  • Federico Rodriguez-Hertz (Penn State University)
  • Ralf Spatzier (University of Michigan)
  • Michele Triestino (Université de Bourgogne)
  • Kurt Vinhage (University of Utah)
  • Zhenqi Wang (Michigan State University)
  • Zhiren Wang (Penn State University)
  • Disheng Xu (Great Bay University)
  • Abdelghani Zeghib (ENS Lyon & CNRS)
  • Zhiyuan Zhang (Université Sorbonne Paris-Nord & CNRS)

* = awaiting confirmation.

Organising committe:

  • Aaron Brown (Northwestern University)
  • David Fisher (Rice University)
  • Kathryn Mann (Cornell University)
  • Vincent Pecastaing (Université Côte d’Azur)
  • Ralf Spatzier (University of Michigan)

Scientific committe:

  • Serge Cantat (Université de Rennes I)
  • Alex Eskin (University of Chicago)
  • Étienne Ghys (ENS Lyon)
  • Federico Rodriguez Hertz (Pennsylvania State University)
  • Amie Wilkinson (University of Chicago)


Back to the thematic trimester main page 


Programme coordinated by the Centre Emile Borel at IHP


Sorbonne Université, CNRS

Amphitheater Hermite / Darboux
11, Rue Pierre et Marie Curie 75005 Paris


Sofiia Minasian: CEB organisational assistant
Sylvie Lhermitte: CEB Manager

Application for this event is currently open.