Saint Louis University Menu Search

(See past events)

Geometry-Topology Seminar

TIME+DATE : 4:10pm--5:00pm Tue 16 Oct 2018
ROOM : 216 Ritter Hall

TITLE: A Proof of Gilman's Conjecture

SPEAKER: Andrew Eisenberg, SLU

ABSTRACT: This talk will cover new research but should still be accessible to graduate students. I will discuss joint work with Adam Piggott proving Gilman's conjecture: any group presented by a finite, monadic, confluent rewriting system must be a free product of finite groups and free groups.

Colloquium

Kenneth Jacobs, Northwestern

Friday, October 19 at 4:00pm in Ritter 231 with refreshments beforehand in the Ritter Hall Lobby.

Reduction Modulo Infinity

Abstract: Reduction modulo a prime number p is a very useful tool in arithmetic geometry, and recently it has been applied to study the dynamics of rational maps with algebraic coefficients. Several authors have presented methods for determining when a given rational map has potential good reduction and / or semistable reduction, both of which describe degeneracy that arises when reducing modulo p. By adapting the method of R. Rumely (UGA), we are able to give new, parallel notions of good reduction / semi-stable reduction for rational maps having arbitrary complex coefficients.

Geometry-Topology Seminar

TIME+DATE : 4:10pm--5:00pm Tue 30 Oct 2018
ROOM : 216 Ritter Hall

TITLE: TBA

SPEAKER: Seth Arnold, SLU

ABSTRACT: TBA

Colloquium

Christopher Connell, Indiana University

Friday, November 2 at 4:00pm in Ritter 231 with refreshments beforehand in the Ritter Hall Lobby.

Homological Norms on Nonpositively Curved Manifolds

Abstract: The Gromov-Thurston norm on the singular homology of a closed manifold provides a topological notion of “volume” for a homology class. On the other hand, every such homology class has a dual cohomology class that can be represented by a unique harmonic differential form (with respect to a Riemannian metric) representing that class via the de Rham isomorphism. Forms come equipped with a natural L2 norm, and the harmonic norm is the L2 norm of this harmonic form. In joint work with Shi Wang, we relate the Gromov-Thurston norm on homology to the harmonic norm on cohomology with upper and lower bounds that depend (necessarily) on the volume and injectivity radius for nonpositively curved manifolds. This extends work of Brock and Dunfield as well as work of Bergeron, Sengun and Venkatesh. We also will discuss some consequences of this relationship between the norms.

Geometry-Topology Seminar

TIME+DATE : 4:10pm--5:00pm Tue 06 Nov 2018
ROOM : 216 Ritter Hall

TITLE: Fibrations with Aspherical Fiber, II: Invariants

SPEAKER: Seth Arnold, SLU

ABSTRACT: TBA 

Geometry-Topology Seminar

TIME+DATE : 4:10pm--5:00pm Tue 27 Nov 2018
ROOM : 216 Ritter Hall

TITLE: Lie Representation Theory, Frames, and Wavelets, I: Introduction

SPEAKER: Brent Wessel, SLU

ABSTRACT: TBA

Geometry-Topology Seminar

TIME+DATE : 4:10pm--5:00pm Tue 04 Dec 2018
ROOM : 216 Ritter Hall

TITLE: Lie Representation Theory, Frames, and Wavelets, II: Oscillator Groups

SPEAKER: Brent Wessel, SLU

ABSTRACT: TBA

Colloquium Schedule

The Math/Stat Colloquium this semester will meet at 4:00pm in RH 231 with refreshments beforehand at 3:30 in the Ritter Lobby.
Our current schedule:

  • Friday, September 7, Haiyan Cai, UMSL (Analysis)
  • Friday, September 21, Keri Kornelson, Oklahoma Univ. (Analysis)
  • Friday, October 5, Elodie Pozzi, Saint Louis University (Analysis)
  • Friday, October 19, Ken Jacobs, Northeastern Univ. (Algebra)
  • Friday, November 2, Chris Connell, Indiana Univ. (Topology)
  • Wednesday, November 14, Shmuel Wienberger, Univ. of Chicago (Topology)