Yves Stalder – Research Yves Stalder Yves

My main research interests are combinatorial (and geometric) group theory and large-scale geometry. I am also interested in connections with operator algebras.

I am more specifically working on Baumslag-Solitar groups, the space of finitely generated groups, coarse embeddings in Hilbert and Banach spaces, Haagerup property, Kazdan's property (T), highly transitive actions, and and dense subgroups of some Polish groups.

I am currently a member of the ANR project GAMME, led by Damien Gaboriau and Romain Tessera.

Formerly, I have been a member of two other ANR projects:

  • the project QuantiT, with Indira Chatterji (project leader), Yves de Cornulier and Vincent Lafforgue;
  • the project AGORA, led by Damien Gaboriau.

    My Ph.D. Thesis is entitled "Espace des groupes marqués et groupes de Baumslag-Solitar" and was awarded by Université de Neuchâtel (Switzerland). My advisor was Alain Valette. The dissertation is available on the digital library RERO DOC.


  • Y. Stalder and A. Valette, Le lemme de Schur pour les représentations orthogonales, Expo. math. 20 (2002), no.3, 279–285.
  • N. Louvet, Y. Stalder, and A. Valette, Fonctions conditionnellement de type négatif, représentations irréductibles et propriété (T), L'Enseign. math. 50 (2004), no.3–4, 239–266.
  • Y. Stalder, Convergence of Baumslag-Solitar groups, Bull. Belg. Math. Soc. Simon Stevin 13 (2006), no. 2, 221–233. ArXiv version
  • Y. Stalder, Moyennabilité intérieure et extensions HNN, Ann. Inst. Fourier (Grenoble) 56 (2006), no. 2, 309–323. ArXiv version
  • Y. Stalder and A. Valette, Wreath products with the integers, proper actions and Hilbert space compression, Geom. Dedicata, 124 (2007), 199–211. (Special issue "Geometric and Probabilistic Methods in Group Theory and Dynamical Systems"). ArXiv version
  • Y. de Cornulier, Y. Stalder, and A. Valette, Proper actions of lamplighter groups associated with free groups, C. R. Acad. Sci. Paris, Ser. I, 346 (2008), 173–176. ArXiv version
  • L. Guyot and Y. Stalder, Limits of Baumslag-Solitar groups, Groups Geom. Dyn. 2 (2008), 353–381. ArXiv version
  • P. Jolissaint and Y. Stalder, Strongly singular MASA's and mixing actions in finite von Neumann algebras, Ergod. Th. & Dynam. Sys. 28 (2008), 1861–1878. ArXiv version
  • Y. Stalder, Fixed point properties in the space of marked groups, in "Limits of graphs in group theory and computer science", Proc. Special semester at Centre Bernoulli (Lausanne), Jan-June 2007, G. Arzhantseva and A. Valette editors, Presses Polytechniques et Universitaires Romandes. ArXiv version
  • Y. de Cornulier, Y. Stalder, and A. Valette, Proper actions of wreath products and generalizations, Trans. Amer. Math. Soc. 364 (2012), 3159-3184 . ArXiv version
  • L. Guyot, and Y. Stalder Limits of Baumslag-Solitar groups and dimension estimates in the space of marked groups, Groups, Geometry, and Dynamics 6 (2012), 533–577. ArXiv version
  • S. Moon, and Y. Stalder, Highly transitive actions of free products, Algebraic & Geometric Topology 13 (2013), 589–607. ArXiv version
  • P. Fima, S. Moon, and Y. Stalder, Highly transitive actions of groups acting on trees, Proc. Amer. Math. Soc. 143 (2015), no. 12, 5083–5095. ArXiv version


  • P. Fima, S. Moon, and Y. Stalder, Homogeneous Actions on the Random Graph. ArXiv version

    If you cannot get a paper which is not on the arXiv, feel free to ask for a copy by e-mail (yves dot stalder at math dot univ-bpclermont dot fr).

    Beamer slides related to some of my talks

  • Plongements bruts dans des espaces de Hilbert, Université d'Orléans, March 2009
  • Ultralimits and fixed-point properties, after Gromov, Conference "Analytic properties of infinite groups", Geneva, August 2008
  • Actions propres de produits en couronne , Université de Bretagne-Sud, Vannes, April 2008

    Accueil | Enseignement