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Tuesday, March 3, 2020

Algebra and Number Theory Seminar  Questions or comments?

Posted February 6, 2020
Last modified February 27, 2020

3:10 pm - 12:00 am 232 Lockett

John Doyle, Louisiana Tech University
Dynamical modular curves and uniform boundedness of preperiodic points

In the mid-1990's, Merel proved the strong uniform boundedness conjecture for torsion points on elliptic curves over number fields. Around the same time, work of Nguyen-Saito and Abramovich established the function field analogue by showing that the gonalities of the modular curves X_1(n) tend to infinity. By studying the geometry of dynamical modular curves, one can prove uniform boundedness for preperiodic points for certain interesting families of polynomial maps over function fields. I will discuss this result as well as a consequence for the dynamical uniform boundedness conjecture over number fields, originally posed by Morton and Silverman. This is joint work with Bjorn Poonen.


Computational Mathematics Seminar  

Posted February 15, 2020

3:30 pm - 4:30 pm Digital Media Center 1034

Li Wang, University of Texas at Arlington
Probabilistic Semi-supervised Learning via Sparse Graph Structure Learning

Abstract: We present a probabilistic semi-supervised learning (SSL) framework based on sparse graph structure learning. Different from existing SSL methods with either a predefined weighted graph heuristically constructed from the input data or a learned graph based on the locally linear embedding assumption, the proposed SSL model is capable of learning a sparse weighted graph from the unlabeled high-dimensional data and a small amount of labeled data, as well as dealing with the noise of the input data. Our representation of the weighted graph is indirectly derived from a unified model of density estimation and pairwise distance preservation in terms of various distance measurements, where latent embeddings are assumed to be random variables following an unknown density function to be learned and pairwise distances are then calculated as the expectations over the density for the model robustness to the data noise. Moreover, the labeled data based on the same distance representations is leveraged to guide the estimated density for better class separation and sparse graph structure learning. A simple inference approach for the embeddings of unlabeled data based on point estimation and kernel representation is presented. Extensive experiments on various data sets show the promising results in the setting of SSL compared with many existing methods, and significant improvements on small amounts of labeled data. div

Wednesday, March 4, 2020

Geometry and Topology Seminar  Seminar website

Posted January 30, 2020

3:30 pm - 4:30 pm Lockett 233

Eva Elduque, University of Michigan
TBA


Harmonic Analysis Seminar  Abstract and additional information

Posted February 7, 2020
Last modified February 16, 2020

3:30 pm - 4:30 pm Lockett 235

Gestur Olafsson, Mathematics Department, LSU
Toeplitz operators and representation theory II

We will discuss the basic ideas how representation theory can be used in the Theory of Toeplitz operators. We start with a general set up of a group acting on a complex manifold with a quasi-invariant measure such that there are non-trivial holomorphic L^2-functions and discuss how that leads to Toeplitz operators. We then introduce several examples. We then connect this to representation theory and explain how representation theory can be used to obtain commutative C^*-algebras of Toeplitz operators. Finally we describe how those ideas can be used to determine the spectrum of the so obtained C^*-algebra by constructing an isomorphism into a L^2-space which is easier to understand. The talks should be accessible to graduate students. We will at least use two seminar talks for the material.

Most of this material is a joint work with M. Dawson and R. Quiroga.

Thursday, March 5, 2020

Colloquium  Questions or comments?

Posted February 9, 2020

3:30 pm - 4:20 pm Lockett 232

Thang Le, Georgia Tech
TBD

Monday, March 9, 2020

Applied Analysis Seminar  Questions or comments?

Posted December 2, 2019

3:30 pm Lockett 233

Rudi Weikard, University of Alabama at Birmingham
Title pending

Wednesday, March 11, 2020

Geometry and Topology Seminar  Seminar website

Posted November 11, 2019

3:30 pm - 4:30 pm Lockett 233

Zhenkun Li, MIT
TBA

Wednesday, March 18, 2020

Geometry and Topology Seminar  Seminar website

Posted February 7, 2020

3:30 pm - 4:30 pm Lockett 233

Mitul Islam, University of Michigan
TBA

Thursday, March 19, 2020

Colloquium  Questions or comments?

Posted January 29, 2020

3:30 pm - 4:20 pm Lockett 232

Phillip Isett, UT Austin
TBD

Tuesday, March 24, 2020

Algebra and Number Theory Seminar  Questions or comments?

Posted January 14, 2020

Spring Break

Tuesday, March 31, 2020

Algebra and Number Theory Seminar  Questions or comments?

Posted January 14, 2020

3:10 pm - 4:00 pm 232 Lockett

Walter Bridges, Louisiana State University
TBA

Wednesday, April 1, 2020

Geometry and Topology Seminar  Seminar website

Posted January 21, 2020

3:30 pm - 4:30 pm Lockett 233

Kyle Hayden, Columbia University
TBA

Tuesday, April 7, 2020

Algebra and Number Theory Seminar  Questions or comments?

Posted January 14, 2020

3:10 pm - 4:00 pm 232 Lockett

Shashika Mestrige, Louisiana State University
TBA

Wednesday, April 8, 2020

Undergraduate Student Colloquium  

Posted February 14, 2020

Steve Butler, Iowa State University
Undergraduate Student Colloquium Talk


Harmonic Analysis Seminar  Abstract and additional information

Posted February 7, 2020
Last modified February 16, 2020

3:30 pm - 4:30 pm Lockett 235

Raul Quiroga, Centro de Investigacion en Matematicas (cimat)
To be Announced

Thursday, April 9, 2020

Graduate Student Colloquium  

Posted February 14, 2020

Steve Butler, Iowa State University
Graduate Student Colloquium

Tuesday, April 21, 2020

Algebra and Number Theory Seminar  Questions or comments?

Posted January 14, 2020
Last modified January 15, 2020

3:10 pm - 4:00 pm 232 Lockett

Alyson Deines, Center for Communications Research La Jolla (CCR-L)
TBA

Thursday, April 23, 2020

Colloquium  Questions or comments?

Posted January 15, 2020

3:30 pm - 4:20 pm Lockett 232

Lenhard Ng, Duke University
TBD

Tuesday, April 28, 2020

Undergraduate Student Colloquium  

Posted January 13, 2020
Last modified February 8, 2020

3:30 pm - 4:30 pm Lockett Hall 243

Shelly Harvey, Rice University
Undergraduate Talk

Wednesday, April 29, 2020

Graduate Student Colloquium  

Posted January 13, 2020
Last modified February 8, 2020

3:30 pm - 4:30 pm Lockett Hall 243

Shelly Harvey, Rice University
Graduate talk