Borel combinatorics and ergodic theory conference  05 - 09 February 2018

Room : BI A0 448

Organisers

Clinton Conley, Carnegie Mellon University

Damien Gaboriau, Ecole Normale Supérieure de Lyon

The study of measurable group actions on standard Borel spaces is of central importance both in descriptive set theory and ergodic theory.

In recent years, the study of (definable) combinatorial structures (such as graphs, simplicial complexes, geometric objects...) has shown itself to be a powerful tool for understanding group actions and also to see what aspects of finite combinatorics generalize into the descriptive milieu. Typical problems to consider are how many colors it takes to color a graph, whether a graph admits a matching or a spanning subtree, what is the smallest dimension of a contractible structure on the orbits, which kinds of geometric group theoretic notions are invariant under orbit equivalence, classification of groups up to orbit equivalence, analysis of full groups of equivalence relations, etc.

In this conference we intend to bring together researchers investigating the abstract combinatorial structures with researchers investigating their incarnations in ergodic theory.
Name University Dates of visit
Miklos Abert MTA Alfréd Rényi Institute of Mathematics 04/02/2018 - 09/02/2018
Gianluca Basso Université de Lausanne, Università di Torino 05/02/2018 - 09/02/2018
Alessandro Carderi Technische Universität Dresden 04/02/2018 - 10/02/2018
Tomasz Cieśla University of Warsaw 05/02/2018 - 09/02/2018
Clinton Conley Carnegie Mellon University 04/02/2018 - 10/02/2018
Endre Csóka Rényi Institute of Mathematics 05/02/2018 - 09/02/2018
Pierre De La Harpe Université de Genève 05/02/2018 - 09/02/2018
Damien Gaboriau Ecole Normale Supérieure de Lyon 04/02/2018 - 09/02/2018
Maxime Gheysens Technische Universität Dresden 04/02/2018 - 10/02/2018
Lukasz Grabowski Lancaster University 04/02/2018 - 10/02/2018
Steve Jackson University of North Texas 04/02/2018 - 10/02/2018
Colin Jahel Paris VII 04/02/2018 - 09/02/2018
Tom Kaiser Unine 05/02/2018 - 09/02/2018
Gabor Kun Eötvös Loránd University 03/02/2018 - 09/02/2018
Corentin Le Coz Université Paris-Sud 03/02/2018 - 09/02/2018
François Le Maître Université Paris Diderot 04/02/2018 - 10/02/2018
Jhih-Huang Li Université de Genève 05/02/2018 - 09/02/2018
Michael Lin Ben Gurion University 05/02/2018 - 09/02/2018
Julien Melleray Institut Camille Jordan, Université Claude Bernard - Lyon 1 04/02/2018 - 10/02/2018
Sam Mellick Central European University 04/02/2018 - 09/02/2018
Valentin Mercier UNINE 05/02/2018 - 09/02/2018
Masato Mimura EPFL 05/02/2018 - 09/02/2018
Mehrzad Monzavi Texas A&M University 03/02/2018 - 09/02/2018
Mikael Pichot McGill University 04/02/2018 - 11/02/2018
Felix Pogorzelski Universität Leipzig 04/02/2018 - 09/02/2018
Sven Raum EPFL 05/02/2018 - 09/02/2018
Roman Sauer Karlsruhe Institute of Technology 04/02/2018 - 10/02/2018
Vasco Schiavo Epfl 05/02/2018 - 09/02/2018
Brandon Seward Courant Institute of Mathematical Sciences, New York 04/02/2018 - 10/02/2018
Nora Gabriella Szoke EPFL 05/02/2018 - 09/02/2018
Anush Tserunyan University of Illinois 04/02/2018 - 10/02/2018
Robin Tucker-Drob Texas A & M University 04/02/2018 - 10/02/2018
László Márton Tóth Central European University, Budapest 04/02/2018 - 09/02/2018
Asger Törnquist University of Copenhagen 04/02/2018 - 07/02/2018
Alain Valette Université de Neuchâtel 05/02/2018 - 09/02/2018
Zoltan Vidnyánszky Universität Wien 05/02/2018 - 09/02/2018
Rafael Zamora Universidad de Costa Rica 04/02/2018 - 11/02/2018
Total Guests : 37
Name University Dates of visit
Miklos Abert MTA Alfréd Rényi Institute of Mathematics 04/02/2018 - 09/02/2018
Alessandro Carderi Technische Universität Dresden 04/02/2018 - 10/02/2018
Lukasz Grabowski Lancaster University 04/02/2018 - 10/02/2018
Gabor Kun Eötvös Loránd University 03/02/2018 - 09/02/2018
François Le Maître Université Paris Diderot 04/02/2018 - 10/02/2018
Julien Melleray Institut Camille Jordan, Université Claude Bernard - Lyon 1 04/02/2018 - 10/02/2018
Mikael Pichot McGill University 04/02/2018 - 11/02/2018
Felix Pogorzelski Universität Leipzig 04/02/2018 - 09/02/2018
Roman Sauer Karlsruhe Institute of Technology 04/02/2018 - 10/02/2018
Brandon Seward Courant Institute of Mathematical Sciences, New York 04/02/2018 - 10/02/2018
Anush Tserunyan University of Illinois 04/02/2018 - 10/02/2018
Robin Tucker-Drob Texas A & M University 04/02/2018 - 10/02/2018
László Márton Tóth Central European University, Budapest 04/02/2018 - 09/02/2018
Asger Törnquist University of Copenhagen 04/02/2018 - 07/02/2018
Rafael Zamora Universidad de Costa Rica 04/02/2018 - 11/02/2018
Total Guests : 15
Monday 5 February
10:00-11:00 CIB front desk registration
11:00-12:00 Roman Sauer Riemannian volume and ergodic group actions
12:00-14:00 Lunch break
14:00-15:00 Gabor Kun Almost automorphisms of sofic approximations
15:00-15:30 Coffee break
15:30-16:30 Julien Melleray Invariant measures of minimal homeomorphisms of a Cantor space

Tuesday 6 February
09:30-10:30 François Le Maître Highly faithful actions and dense free groups in full groups
10:30-11:00 Coffee break
11:00-12:00 Felix Pogorzelski The Ihara zeta function for measured graphs
12:00-14:00 Lunch break
14:00-15:00 Miklos Abert Point processes, cost and weak containment of locally compact groups
15:00-15:30 Coffee break
15:30-16:30 Asger Törnquist The τ-invariant and classification of factors of type III

Wednesday 7 February
09:30-10:30 Anush Tserunyan A pointwise ergodic theorem for quasi-pmp graphs
10:30-11:00 Coffee break
11:00-12:00 Lukasz Grabowski Borel and measurable versions of the Lovasz Local Lemma
Social outing

Thursday 8 February
09:30-10:30 Brandon Seward Bernoullicity and treeability
10:30-11:00 Coffee break
11:00-12:00 Rafael Zamora Finding basis for quasi-orders related to graphs
12:00-14:00 Lunch break
14:00-15:00 László Márton Tóth Invariant random subgroups of groups acting on rooted trees
15:00-15:30 Coffee break
15:30-16:30 Alessandro Carderi Asymptotic invariants of lattices in locally compact groups
17:15-18:15 Steve Jackson's        Bernoulli Lecture Undecidability in the Theory of Abelian Group Actions

Friday 9 February
09:30-10:30 Mikael Pichot Discrete groups of rank 7/4
10:30-11:00 Coffee break
11:00-12:00 Robin Tucker-Drob Superrigidity and measure equivalence