Past talks
Spring 2021
Jan 12. Alex Furman: Besson-Courtois-Gallot [ETDS 1996]
Jan 19. Alex Furman: Besson-Courtois-Gallot, cont.
Jan 26. Wouter Van Limbeek: Degree theorem in higher rank, after Connell-Farb
Feb 2. Mikolaj Fraczyk: Vanishing of homology, after Connell-Farb-McReynolds
Feb 9. Sebastian Hurtado: Rigidity of amalgamated products, after Besson-Courtois-Gallot
Feb 16. Ethan Fricker: Marked length rigidity for surfaces, after Otal
Feb 23. Alex Furman: Simplicial volume and Gromov-Thurston proof of Mostow rigidity for SO(n,1) n>2
Mar 2. Sam Dodds: Positivity of simplicial volume for locally symmetric manifolds, after Lafont-Schmidt
Mar 9. Wouter Van Limbeek: Introduction to bounded cohomology
Mar 16. Wouter Van Limbeek: Introduction to bounded cohomology (continued)
Mar 25: No seminar (Spring break)
Mar 30: Yanlong Hao: Bounded Euler class and actions on the circle after Ghys
April 6: Alex Furman: Volume rigidity of representations of hyperbolic lattices
April 13: Alex Furman: Measure Equivalence Rigidity vs. Mostow rigidity
April 20: Yanlong Hao: Some examples of surface group actions on the circle
April 27: Steve Cantrell: The Manhattan curve and rigidity
Fall 2020
Sept 8. Alex Furman: Some Intro, Planning, and Discussions.
Sept 15. Alex Furman: Proximal elements in Zariski dense semi-groups
Sept 22. Alex Furman/ Homin Lee: Loxodromic elements and Jordan projection
Sept 29. Homin Lee: Benoist's theorem on Cartan projections
Oct 6. Homin Lee / Wouter van Limbeek: Benoist's theorem on Cartan projections
Oct 13. Wouter van Limbeek: Quotients of homogeneous spaces 2
Oct 20. Wouter van Limbeek: Quotients of homogeneous spaces 3
Oct 27. Mikolaj Fraczyk: Compact forms and decay of matrix coefficients (after Margulis)
Nov 10. Sam Dodds: Joint spectrum (after Breuillard and Sert)
Nov 17. Sam Dodds: Joint spectrum II (after Breuillard and Sert)
Dec 1. Alex Furman: Uniform independence in linear groups (after Breuillard-Gelander)
Spring 2020
Jan 21. Alex Furman: Arithmeticity of hyperbolic manifolds with many totally geodesic submanifolds (after Bader, Fisher, Miller, Stover)
Jan 28. Alex Furman: Arithmeticity of hyperbolic manifolds with many totally geodesic submanifolds II (after Bader, Fisher, Miller, Stover)
Feb 4. Yanlong Hao: Hyperbolic groups admit proper isometric actions on L^p-spaces with large p (after Nica).
Feb 11. Alex Furman: Kazhdan groups have finite image in Diff^2(S^1).
Feb 18. Ethan Fricker: Locally symmetric metrics minimize entropy under curvature bound (after Hamenstadt).
Feb 25. Alex Furman: Holder's theorem and other Simultaneous Conjugation Problems.
Fall 2019 (Negatively curvature and growth)
Aug 27, Alex Furman: Organizational and Introductory talk
Sept 3, Sam Dodds: Patterson-Sullivan Theory I
Sept 10, Sam Dodds: Patterson-Sullivan Theory II
Sept 17, Sam Dodds: Patterson-Sullivan Theory III
Sept 24, Alex Furman: Patterson-Sullivan Theory IV
Oct 1, Yanlong Hao: Boundary representations for hyperbolic groups
Oct 9, Yanlong Hao: Boundary representations for hyperbolic groups II
Oct 15, Alex Furman: Burger's Manhattan curve, and Patterson-Sullivan measures in products of hyperbolic spaces
Oct 22, Wouter Van Limbeek: Quasicircle boundaries and exotic almost-isometries
Oct 29, Subhadip Dey, Orbits of Anosov subgroups from a Finsler point of view
Nov 5, Sebastian Hurtado: Growth gap for groups acting on quaternionic hyperbolic space (after Corlette)
Nov 19, Wouter van Limbeek: Maximal critical exponents via twisted Patterson-Sullivan measures (after Coulon-Dougall-Schapira-Tapie)
Spring 2019 (L^2-Betti numbers, B-S convergence, IRS, 7 Samurai paper/s):
Jan 23. Alex Furman: Introduction to the 7s paper
Feb 6. Wouter Van Limbeek: L^2-Betti numbers and Luck's Approximation Theorem
Feb 13. Wouter Van Limbeek: L^2-Betti numbers and Luck's Approximation Theorem (cont.)
Feb 20. Sam Dodds: Introduction to IRS (Invariant Random Subgroups)
Feb 27. Sarnak's Lecture SeriesMar 6. Yanglong Hao: IRS and Benjamini-Schramm convergence of locally symmetric spaces
Mar 13. Mikolaj Fraczyk: Benjamini-Schramm convergence for congruence arithmetic lattices
Mar 20. Alex Furman: On some theorems of Margulis, Stuck-Zimmer, Peterson and IRS
Apr 3. Alex Furman: Margulis' Normal Subgroup Theorem
Apr 17. Sebastian Hurtado: Heat flow and asymptotic of Betti numbers.
Apr 24. Wouter Van Limbeek: Constructions of exotic IRS in rank one groups.
Fall 2018 Talks
September 11. Samuel Dodds: Hausdorff-Banach-Tarski "paradox"
September 18. Samuel Dodds: Banach-Ruziewicz problem on S^n with n>3 using property (T) (see [L] Section 3.4)
September 25. Wouter van Limbeek: Benoist-de Saxce paper, I.
October 2. Robert Kozma: Tarski's theorem - non-amenable groups are paradoxical.
October 16. Alex Furman: Sharp ergodic theorems along random walks for actions with spectral gap.
October 23. Alex Furman: Introduction to Bourgain-Gamburd machine.
October 30. Alex Furman: Bourgain-Gamburd machine, II.
November 6. Wouter van Limbeek: Weak version of Selberg's Theorem.
November 13. Sebastian Hurtado: Balog-Szemeredi-Gowers Lemma.
November 20. Wouter Van Limbeek: Benoist-de Saxce paper, II.
Spring 2018 Talks:
February 7. Organizational meeting and/or a short talk about "Aut(F_5) has property (T)"
February 28. Alex Furman: Properties of harmonic measure for a random walk on SL(d,R)
March 7. Alex Furman: On continuity of Lyapunov exponents
March 14. Alex Furman: On Gromov-Thurston's proof of Mostow rigidity
April 11, 25. Alex Furman: A theorem of Besson-Courtois-Gallot.
Fall 2017 talks:
September 7. Alex Furman: Intro to Ozawa's paper - affine isometric actions on Hilbert spaces
September 14. Olga Lukina: Selberg's lemma
September 21. Alex Furman: Reduced cohomology and harmonic cocycles
September 28. Sam Dodds: Polynomial growth and vanishing of reduced cohomology under weak mixing
October 5. Alex Furman: Groups without (T) have non-trivial reduced cohomology
October 19. Yanlong Hao: Congruence Subgroup Property
Oct 26, Nov 2. Jake Herndon: Boundedness of the homeomorphism group of a sphere
November 9, 16. Alex Furman: Oseledets Theorem
November 30. Alex Furman: Intro to random walks on semi-simple Lie groups
December 7. Alex Furman: Intro to harmonic functions and Furstenberg-Poisson boundary