# Mathematical Sciences Research Institute

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1. # Postdoc Seminar I: The action dimension and the obstructor dimension of a discrete group

Location: MSRI: Simons Auditorium
Speakers: Giang Le (MSRI - Mathematical Sciences Research Institute)
Updated on Oct 13, 2016 03:45 PM PDT
2. # Postdoc Seminar II: Small cancellation monsters - a crash course

Location: MSRI: Simons Auditorium
Speakers: Dominik Gruber (ETH Zürich)

Small cancellation theory is a tool for constructing and studying infinite monster groups: finitely generated groups with extreme algebraic, geometric, and analytic properties. I will explain the fundamental idea that the Euler characteristic formula for planar graphs enables constructions of such groups. I will discuss how the recent geometric notion of acylindrical hyperbolicity has led us to the first strong structural results about large classes of monster groups (joint work with A. Sisto). Moreover, I will explain how this geometric viewpoint has enabled us to develop an easy-to-apply tool for constructing new examples of infinite bounded torsion groups (joint work with R. Coulon).

Updated on Oct 13, 2016 03:45 PM PDT

1. # Working Seminar: Formal Languages and Geometry

Location: MSRI: Baker Board Room
Speakers: Robert Gilman (Stevens Institute of Technology)

We will investigate new developments concerning connections between the logical complexity of formal languages attached to groups and geometric properties of the groups.

Updated on Oct 20, 2016 12:58 PM PDT
2. # Working Seminar: Projection complexes, rotating families, and beyond

Location: MSRI: Baker Board Room
Created on Sep 13, 2016 10:11 AM PDT
3. # Working Seminar: Formal Languages and Geometry

Location: MSRI: Baker Board Room
Updated on Oct 20, 2016 01:03 PM PDT
4. # Working Seminar: Projection complexes, rotating families, and beyond

Location: MSRI: Baker Board Room
Created on Sep 13, 2016 10:11 AM PDT
5. # Member Seminar: Equidistribution and counting for group actions on trees

Location: MSRI: Simons Auditorium
Speakers: Frédéric Paulin (Université Paris-Saclay)

Given a discrete group $\Gamma$ of automorphisms of a uniform tree $T$, we will give counting and equidistribution results of common perpendiculars between two locally finite orbits of subtrees of $T$ when their lengths tend to $\infty$. Applications will be given to equidistribution results of rational and quadratic irrational elements in local fields of positive characteristic. This is joint work with A.~Broise and J.~Parkkonen.

Updated on Oct 18, 2016 08:57 AM PDT
6. # Working Seminar: Counting problems in groups and spaces, and random walks

Location: MSRI: Simons Auditorium
Updated on Sep 13, 2016 09:41 AM PDT
7. # Common Lunch

Location: MSRI: Commons Room
Created on Aug 25, 2016 01:49 PM PDT

Location: MSRI: Commons Room
Created on Sep 13, 2016 09:50 AM PDT

Location: MSRI: Baker Board Room
Updated on Oct 07, 2016 10:37 AM PDT
10. # Working Seminar: Out(Fn) - complexes

Location: MSRI: Baker Board Room
Created on Oct 11, 2016 01:30 PM PDT
11. # Postdoc Seminar I

Location: MSRI: Simons Auditorium
Updated on Aug 26, 2016 09:25 AM PDT
12. # Postdoc Seminar II

Location: MSRI: Simons Auditorium
Created on Aug 26, 2016 09:32 AM PDT
13. # Working Seminar: Formal Languages and Geometry

Location: MSRI: Baker Board Room
Updated on Oct 20, 2016 01:03 PM PDT
14. # Working Seminar: Projection complexes, rotating families, and beyond

Location: MSRI: Baker Board Room
Created on Sep 13, 2016 10:12 AM PDT
15. # Member Seminar: Actions of Cremona groups on CAT(0) cube complexes and applications

Location: MSRI: Simons Auditorium
Speakers: Yves Cornulier (Centre National de la Recherche Scientifique (CNRS))

The group of birational transformation of an irreducible variety has a partially defined action on the set of hypersurfaces: for a given transformation, this action is defined on all hypersurfaces but finitely many. This can be extended to an action by a canonical procedure; the resulting action can also be made explicit using basic algebraic geometry: it acts on the set of all hypersurfaces of all birational models of X, suitably defined.  This action "commensurates" the subset of those hypersurfaces that are in the original variety. This is known to induce an action on a CAT(0) cube complex. This construction allows, when a group is known to have restrictions on its actions on CAT(0) cube complex (such as Property FW: every action on any CAT(0) cube complex has a fixed point), to provide restrictions on its birational actions on varieties. The most optimistic conclusion is to prove that the action is by variety automorphisms on some model; we can reach this conclusion for birational actions on surfaces of groups with Proprety FW.

I will carefully define the basic definitions, both on the side of CAT(0) cube complexes, and especially on the algebraic geometry side (where I will essentially only consider the projective plane), so that the talk requires no prerequisite in algebraic geometry.

Updated on Oct 19, 2016 08:42 AM PDT
16. # Working Seminar: Counting problems in groups and spaces, and random walks

Location: MSRI: Simons Auditorium
Created on Sep 13, 2016 09:42 AM PDT
17. # Common Lunch

Location: MSRI: Commons Room
Created on Aug 25, 2016 01:50 PM PDT

Location: MSRI: Baker Board Room
Updated on Oct 07, 2016 10:38 AM PDT
19. # Working Seminar: Out(Fn) - complexes

Location: MSRI: Baker Board Room
Created on Oct 11, 2016 01:31 PM PDT
20. # Postdoc Seminar I

Location: MSRI: Simons Auditorium
Created on Aug 26, 2016 09:26 AM PDT
21. # Postdoc Seminar II

Location: MSRI: Simons Auditorium
Created on Aug 26, 2016 09:32 AM PDT
22. # Working Seminar: Formal Languages and Geometry

Location: MSRI: Baker Board Room
Updated on Oct 20, 2016 01:04 PM PDT
23. # Working Seminar: Projection complexes, rotating families, and beyond

Location: MSRI: Baker Board Room
Created on Sep 13, 2016 10:13 AM PDT
24. # Member Seminar

Location: MSRI: Simons Auditorium
Created on Aug 25, 2016 02:00 PM PDT
25. # Working Seminar: Counting problems in groups and spaces, and random walks

Location: MSRI: Simons Auditorium
Created on Sep 13, 2016 09:43 AM PDT
26. # Common Lunch

Location: MSRI: Commons Room
Created on Aug 25, 2016 01:50 PM PDT

Location: MSRI: Baker Board Room
Updated on Oct 07, 2016 10:38 AM PDT
28. # Working Seminar: Out(Fn) - complexes

Location: MSRI: Baker Board Room
Created on Oct 11, 2016 01:31 PM PDT
29. # Postdoc Seminar I

Location: MSRI: Simons Auditorium
Created on Aug 26, 2016 09:34 AM PDT
30. # Postdoc Seminar II

Location: MSRI: Simons Auditorium
Created on Aug 26, 2016 09:33 AM PDT
31. # Working Seminar: Formal Languages and Geometry

Location: MSRI: Baker Board Room
Updated on Oct 20, 2016 01:04 PM PDT
32. # Working Seminar: Projection complexes, rotating families, and beyond

Location: MSRI: Baker Board Room
Created on Sep 13, 2016 10:14 AM PDT
33. # Member Seminar

Location: MSRI: Simons Auditorium
Created on Aug 25, 2016 02:01 PM PDT
34. # Working Seminar: Counting problems in groups and spaces, and random walks

Location: MSRI: Simons Auditorium
Created on Sep 13, 2016 09:43 AM PDT
35. # Common Lunch

Location: MSRI: Commons Room
Created on Aug 25, 2016 01:52 PM PDT
36. # Working Seminar: Formal Languages and Geometry

Location: MSRI: Baker Board Room
Updated on Oct 20, 2016 01:04 PM PDT
37. # Working Seminar: Projection complexes, rotating families, and beyond

Location: MSRI: Baker Board Room
Created on Sep 13, 2016 10:15 AM PDT
38. # Member Seminar

Location: MSRI: Simons Auditorium
Created on Aug 25, 2016 02:01 PM PDT
39. # Working Seminar: Counting problems in groups and spaces, and random walks

Location: MSRI: Simons Auditorium
Created on Sep 13, 2016 09:44 AM PDT
40. # Common Lunch

Location: MSRI: Commons Room
Created on Aug 25, 2016 01:53 PM PDT

Location: MSRI: Baker Board Room
Updated on Oct 07, 2016 10:38 AM PDT
42. # Working Seminar: Out(Fn) - complexes

Location: MSRI: Baker Board Room
Created on Oct 11, 2016 01:32 PM PDT
43. # Postdoc Seminar I

Location: MSRI: Simons Auditorium
Created on Aug 26, 2016 09:26 AM PDT
44. # Postdoc Seminar II

Location: MSRI: Simons Auditorium
Created on Aug 26, 2016 09:34 AM PDT

seminar
1. # SeminarWorking Seminar: Out(Fn) - complexes

Created on Sep 13, 2016 09:54 AM PDT

Updated on Oct 07, 2016 10:37 AM PDT
3. # SeminarTopology Seminar (Main Talk): Cohomology of the mapping class group via cup products in surface bundles

Created on Oct 13, 2016 10:31 AM PDT
4. # SeminarTopology Seminar (Introductory Talk): Surface bundles and the mapping class group

Created on Oct 13, 2016 10:30 AM PDT
5. # SeminarCommon Lunch

Created on Aug 25, 2016 01:48 PM PDT
6. # SeminarWorking Seminar: Counting problems in groups and spaces, and random walks

Created on Sep 13, 2016 09:40 AM PDT
7. # Seminar3-Manifold Seminar: Property R

Created on Oct 13, 2016 11:53 AM PDT
8. # SeminarWorking Seminar: Median Spaces

Created on Sep 13, 2016 09:57 AM PDT
9. # SeminarMember Seminar: Cannon-Thurston maps for hyperbolic free group extensions

Updated on Sep 20, 2016 03:53 PM PDT
10. # SeminarWorking Seminar: Projection complexes, rotating families, and beyond

Created on Sep 13, 2016 10:10 AM PDT
11. # SeminarPostdoc Seminar II: On the geometry of the flip graph

Updated on Oct 07, 2016 08:53 AM PDT
12. # SeminarPostdoc Seminar I: Job Talk: Constructing generic elements in Out(F_n) and mapping class group

Updated on Oct 12, 2016 12:26 PM PDT
13. # SeminarWorking Seminar: Out(Fn) - complexes

Created on Sep 13, 2016 09:48 AM PDT

Updated on Oct 07, 2016 09:18 AM PDT
15. # SeminarTopology Seminar: The stratum of a random mapping class

Created on Oct 06, 2016 02:29 PM PDT
16. # SeminarTopology Seminar: An introductory survey of random walks on the mapping class group

Created on Oct 06, 2016 02:27 PM PDT
17. # SeminarCommon Lunch

Created on Aug 25, 2016 01:47 PM PDT
18. # Seminar3-Manifold Seminar: Thin position for knots and Property R

Created on Oct 06, 2016 09:42 AM PDT
19. # SeminarMember Seminar: Discontinuous Motions of limit sets

Updated on Sep 20, 2016 03:59 PM PDT
20. # SeminarWorking Seminar: Projection complexes, rotating families, and beyond

Created on Sep 13, 2016 10:09 AM PDT
21. # SeminarProbabilistic Operator Algebra Seminar: The C*-algebra of lamplighter groups over finite groups

Updated on Oct 06, 2016 09:20 AM PDT
22. # SeminarWorking Seminar: Ozawa's proof of Gromov's polynomial growth theorem: Ozawa's functional-analytic proof

Created on Sep 29, 2016 04:26 PM PDT
23. # SeminarPostdoc Seminar II: Introduction to Elementary Theory of Free groups

Updated on Sep 30, 2016 08:42 AM PDT
24. # SeminarPostdoc Seminar I: Relatively Hyperbolic Surface Amalgams

Updated on Sep 30, 2016 08:41 AM PDT
25. # SeminarBerkeley Math Dept. Colloquiua: Dynamics and polynomial invariants of free-by-cyclic groups

Created on Oct 03, 2016 03:17 PM PDT
26. # SeminarWorking Seminar: Out(Fn) - complexes

Created on Sep 13, 2016 09:48 AM PDT
27. # SeminarGraduate Student Seminar: Bounded Cohomology

Updated on Oct 06, 2016 08:40 AM PDT
28. # SeminarCommon Lunch

Created on Aug 25, 2016 01:46 PM PDT
29. # SeminarWorking Seminar: Counting problems in groups and spaces, and random walks

Created on Sep 13, 2016 09:39 AM PDT
30. # SeminarUC Berkeley 3-Manifold Seminar: Sutured manifolds

Created on Oct 03, 2016 04:39 PM PDT
There are more then 30 past seminars. Please go to Past seminars to see all past seminars.