Calendar

Posted August 22, 2026

Algebra and Number Theory Seminar Questions or comments?

Isabella Negrini, University of Toronto
TBA

Event contact: Gene Kopp

Posted November 4, 2026
Last modified November 5, 2026

Colloquium Questions or comments?

Yi Han, Massachusetts Institute of Technology
What Shapes a Random Spectrum?

A large Ginibre matrix fills a disk uniformly with its eigenvalues. A polynomial in several such matrices can produce a very different shape. I will present my work on Brown measure convergence for polynomials in independent complex Ginibre matrices. The proof decomposes a linearization into algebraically irreducible pieces, yielding high-probability lower bounds of the form (N^{-C}) for the least singular value.

I will then present a new approach to inhomogeneous non-Hermitian spectra through direct comparison of logarithmic determinants and transfer-matrix methods, with applications to circular laws at arbitrarily slowly growing bandwidth.

I will also discuss an answer, in unfolded coordinates, to Bourgain’s question about Poisson eigenvalue statistics for one-dimensional Anderson–Bernoulli operators. I will close with uniqueness in law for the scalar stochastic heat equation with uniformly nondegenerate diffusion coefficients of every positive Hölder exponent.

Posted August 26, 2026

Informal Analysis Seminar Questions or comments?

Ruben Acevedo Acevedo, Louisiana State University
TBD (Spectral Theory)

Posted September 15, 2026
Last modified November 1, 2026

Geometry and Topology Seminar Seminar website

Federico Galetto, Cleveland State University
Homology of Vietoris-Rips complexes of hypercube graphs

The Vietoris-Rips complex of a point set in a metric space is the simplicial complex of finite subsets of the point set whose elements have mutual distance less than or equal to a given parameter. Our point set is the set of vertices of a hypercube graph equipped with the Hamming distance, and the resulting simplicial complex is symmetric under the action of the automorphism group of the hypercube graph. I will illustrate how this symmetry can be used to compute the homology of some of these Vietoris-Rips complexes. This is joint work with Jonathan Montaño and Zoe Wellner.

Event contact: Christin Bibby

Posted November 4, 2026
Last modified November 5, 2026

Colloquium Questions or comments?

Joe Jackson, University of Chicago
The Mean-Field Limit of Online Stochastic Vector Balancing

This talk will be about recent joint work with Christian Fiedler, Daniel Lacker, and Jonathan Niles-Weed, in which we derive a mean-field scaling limit for a class of combinatorial optimization problems. In particular, we study a stochastic online version of the vector balancing problem: $n$ independent Gaussian random vectors $\mathbf{\zeta}(1),\dots,\mathbf{\zeta}(n) \sim \mathcal{N}(0,I_n)$, each of dimension $n$, arrive one at a time. The goal is to choose signs $\varepsilon(1),\dots,\varepsilon(n) \in \{-1,1\}$, with $\varepsilon(k)$ depending only on $\mathbf{\zeta}(1),\dots,\mathbf{\zeta}(k)$, so as to minimize the expected $\ell^\infty$ norm of the signed sum $\frac{1}{\sqrt{n}}\sum_{k=1}^n \varepsilon(k)\mathbf{\zeta}(k)$. Prior work showed that the optimal value $V^n$ is $O(1)$, at least for vectors with independent Rademacher entries, by constructing and analyzing specific algorithms. Our main contribution is to prove that $V^n$ converges and to characterize its limit $V^\infty$ as the value of a nonstandard stochastic control problem of mean-field type.

Posted August 27, 2026
Last modified October 13, 2026

Informal Geometry and Topology Seminar Questions or comments?

Yongho Lee, Louisiana State University
TBD

TBD

Posted November 2, 2026
Last modified November 5, 2026

Applied Analysis Seminar Questions or comments?

Zhongkai Tao, IHES
TBA

Posted November 4, 2026
Last modified November 6, 2026

Colloquium Questions or comments?

Erik Bates, North Carolina State University
Longest convex chains...a new universality class?

In the study of random growth processes, a foundational model is the longest-increasing-subsequence problem: from $n$ independent uniform points in the unit square, find the longest chain whose horizontal and vertical coordinates are both increasing. It is known that the maximal length is asymptotically $2n^{1/2}$, and the longest chain concentrates near the diagonal line $y=x$. In this talk, we add a geometric constraint: the chain must be convex. I will discuss the history of this problem, why I care about it, and what we know so far from recent joint work with Arnab Sen.

Posted October 28, 2026

LSU SIAM Student Chapter

Applied Math Social

Do you use math in your research? Whether you're modeling populations, training neural nets, or running statistics on lab data, join LSU's Society for Industrial and Applied Mathematics (SIAM) on November 12th at 4 PM for an evening of games, food, and networking with people across campus who put math to work. It's a chance to meet potential collaborators and trade research ideas. Grad students, postdocs, faculty, and curious undergrads from all fields are welcome.(This is an interdisciplinary event for many departments.)

Posted September 21, 2026
Last modified November 3, 2026

Control and Optimization Seminar Questions or comments?

Radu Bot, University of Vienna
Continuous- and Discrete-Time Methods in Convex Optimization and Monotone Inclusions

In this talk, we explore the interplay between continuous-time and discrete-time models for solving convex optimization problems and monotone inclusions. We discuss strategies for achieving faster convergence rates across the different settings, as well as issues related to the convergence of trajectories and iterates.