Calendar

Time interval: Events:

Tomorrow, Monday, November 2, 2026

Posted October 31, 2026

2:30 pm – 3:30 pm Lockett 233

Joy Harris, Louisiana State University
Equitable Graph Colorings

Say that we are running a factory and we need to assign workers to tasks within that factory. In order to avoid cross contamination, we specify that certain pairs of tasks should not be completed by the same worker. We can think of the tasks as the vertices of a graph, and pairs of tasks that are incompatible will have an edge between them. Now color each vertex based on which worker we have assigned to the task. Ideally, we want that none of the tasks assigned to the same worker are incompatible, i.e. none of the vertices of the same color have an edge between them. This is exactly the idea behind a proper vertex coloring of a graph. Let's add an extra condition. It's not fair to one worker if they must work twice as many tasks as their peers. We specify that each worker must be assigned to the same amount of tasks, give or take one. In the graph, this means that each vertex color class must be the same size, give or take one vertex. We have now entered the world of equitable vertex graph colorings. We will see how equitable graph vertex colorings differ from vertex colorings, discuss the Chen-Lih-Wu conjecture and what's known, and then prove some basic results that give the flavor of the methods used in the proof of the conjecture.

Event contact: jgarc86@lsu.edu

Wednesday, November 4, 2026

Posted August 26, 2026

Informal Analysis Seminar Questions or comments?

12:30 pm – 1:20 pm Lockett 233

Jackson Knox, Louisiana State University
TBD (Dynamical Systems)

Event contact: Laura Kurtz

Posted September 25, 2026
Last modified October 17, 2026

Geometry and Topology Seminar Seminar website

1:30 pm – 2:30 pm Lockett 233

Steven Clontz, University of South Alabama
Database-Driven Mathematical Inquiry in Topology

Recent advances in computing have changed not only the nature of mathematical computation, but mathematical proof and inquiry itself. While artificial intelligence and formalized mathematics have been the major topics of this conversation, this talk will explore another class of tools for advancing mathematics research: databases of mathematical objects that enable semantic search, particularly the π-Base community database of topological counterexamples

Posted August 27, 2026

Informal Geometry and Topology Seminar Questions or comments?

3:30 pm Lockett Hall 233

Michael Young, Louisiana State University
TBD

TBD

Thursday, November 5, 2026

Posted October 16, 2026

Student Colloquium

10:30 pm TBD

Steven Clontz, University of South Alabama
Accessible and Interactive Mathematical Documents for Instruction

Beginning April 26, 2027, all public universities will be required to ensure digital documents posted online must be accessible to screenreader users. Compliance with the Americans with Disabilities Act can be quite tricky in mathematics, given our reliance on intricate formulas and graphics, and even interactive elements such as code or three-dimensional renders, for research and education. In this talk we will explore three particular tools for meeting this upcoming accessibility requirement: PreTeXt, Prefigure, and Doenet.

Friday, November 6, 2026

Posted September 30, 2026

Control and Optimization Seminar Questions or comments?

10:30 am – 11:20 am Zoom: https://lsu.zoom.us/j/98176468969

Daniel Wachsmuth, University of Wuerzburg, Germany
Solution Algorithms for Nonsmooth Optimal Control Problems Based on the Pontryagin Maximum Principle

The talk is motivated by optimal control problems for partial differential equations. The main interest is in problems that involve integral functions of the type \[\int_\Omega g(u(x)) \ dx,\] where $g : \mathbb R \to \mathbb R$ is nonsmooth and nonconvex, and $u$ is the control variable. Examples involve $L^{\scriptscriptstyle r}$-pseudonorms with $r\in [0,1)$ or problems with the constraint $u(x) \in \mathbb Z$ for $x\in \Omega$. Due to the nonconvexity of $g$, the existence of solutions in $L^{\scriptscriptstyle p}$-spaces cannot be proven. Local solutions (if they exist) can be proven to satisfy the Pontryagin maximum principle. A distinctive feature of this result is that no differentiability with respect to the control variable $u$ is required. The maximum principle serves as a starting point to develop an implementable solution algorithm. We prove that the residual in the maximum principle vanishes along the iterates produced by the algorithm. Under additional assumptions, the iterates are a minimizing sequence.

Tuesday, November 10, 2026

Posted August 22, 2026

Algebra and Number Theory Seminar Questions or comments?

3:00 pm – 4:00 pm Lockett 233 or click here to attend on Zoom

Isabella Negrini, University of Toronto
TBA

Event contact: Gene Kopp

Wednesday, November 11, 2026

Posted August 26, 2026

Informal Analysis Seminar Questions or comments?

12:30 pm – 1:20 pm Lockett 233

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

Posted September 15, 2026
Last modified November 1, 2026

Geometry and Topology Seminar Seminar website

1:30 pm – 2:30 pm Lockett 233

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 August 27, 2026
Last modified October 13, 2026

Informal Geometry and Topology Seminar Questions or comments?

3:30 pm Lockett Hall 233

Yongho Lee, Louisiana State University
TBD

TBD

Friday, November 13, 2026

Posted September 21, 2026

Control and Optimization Seminar Questions or comments?

10:30 am – 11:20 am Zoom: https://lsu.zoom.us/j/98176468969

Radu Bot, University of Vienna
TBA

Tuesday, November 17, 2026

Posted September 20, 2026

Algebra and Number Theory Seminar Questions or comments?

3:00 pm – 4:00 pm Lockett 233 or click here to attend on Zoom

Ngoc Trinh Le, Tulane University
TBA

Event contact: Gene Kopp

Posted September 30, 2026
Last modified October 17, 2026

Computational Mathematics Seminar

3:30 pm – 4:20 pm LDMC, Room 1034

Gonzalo Benavides, University of Maryland
A priori error analysis of conforming discretizations of the ferrofluids Shliomis model without magnetic regularization

We develop and analyze a family of conforming, energy-stable spatial semidiscretizations of the Shliomis ferrofluid model without magnetic diffusion in two and three space dimensions. The limited spatial control supplied by the energy law complicates the treatment of magnetic nonlinearities in the error analysis. Our formulation retains the rotational coupling and incorporates the magnetic normal-flux condition naturally, overcoming the dimensional restriction and boundary-enforcement difficulties of the two-potential approach of Benavides, Nochetto and Shakipov (2026). The error analysis combines consistent stabilization of the Maxwell constraint with a cancellation arising from exact incompressibility and the pointwise symmetry of the Hessian of the magnetic potential. We prove global solvability and establish a priori error estimates for sufficiently regular exact solutions under explicit approximation and projection-stability assumptions. These assumptions are verified for concrete finite element spaces in two dimensions, while the three-dimensional error estimates remain conditional on a highly likely, but still unverified, uniform $\mathrm{W}^{1,\infty}$-stability of an appropriate incompressibility-preserving projector. Of independent interest and following Girault and Scott (2002), we construct an averaged $\mathrm{H}^2$-conforming projector that is well-defined on $\mathrm{L}^1(\Omega)$. For the Hsieh--Clough--Tocher and Walkington macroelement families considered, we establish optimal approximation estimates in $\mathrm{W}^{j,p}(\Omega)$, $j=0,1,2$, and stability in $\mathrm{W}^{2,p}(\Omega)$ for every $p \in [1,\infty]$ on general shape-regular triangulations.

Event contact: Shawn Walker

Wednesday, November 18, 2026

Posted August 26, 2026

Informal Analysis Seminar Questions or comments?

12:30 pm – 1:20 pm Lockett 233

Moisés Gómez-Solís, Louisiana State University
TBD (Spectral Theory)

Event contact: Laura Kurtz

Posted September 15, 2026
Last modified October 31, 2026

Geometry and Topology Seminar Seminar website

1:30 pm – 2:30 pm Lockett 233

Kushlam Srivastava, University of Wisconsin-Milwaukee
Parabolic cut pairs in boundaries of relatively hyperbolic groups

Given a relatively hyperbolic group, the topology of its Bowditch boundary is useful in understanding the underlying relatively hyperbolic structure. For example, for a connected boundary, we know from the work of Hruska–Dasgupta that the cut points are parabolic and correspond to a parabolic splitting of the group. We also know from work of Haulmark–Hruska that inseparable loxodromic cut pairs correspond to splittings over 2–ended subgroups. For some time, it was suspected that inseparable cut pairs on the boundary can only be loxodromic. However, examples of parabolic cut pairs were discovered by Hruska–Walsh. In this talk, we will present a combination theorem for relatively hyperbolic groups, which results in such parabolic cut pairs on their boundaries. We will also see that all relatively hyperbolic groups with parabolic cut pairs are characterized via this theorem.

Event contact: Pallavi Dani

Posted August 27, 2026
Last modified September 25, 2026

Informal Geometry and Topology Seminar Questions or comments?

3:30 pm Lockett Hall 233

Peter Ramsey, Louisiana State University
TBD

TBD

Thursday, November 19, 2026

Posted September 10, 2026

Colloquium Questions or comments?

3:30 pm Lockett 232

Maria Chudnovsky, Princeton University MacArthur Foundation Fellowship recipient 2012.
TBA

Friday, November 20, 2026