University of North Texas 
Millican Colloquium
- Faculty Research Interests
- Millican Colloquium
- Algebra Seminar
- Applied and Computational Mathematics Seminar
- Dynamical Systems Seminar
- Logic Seminar
- STaRS - Students Talk Research Seminar
- Math Conferences at UNT
- Master's and Doctoral Defenses
Millican lectures are made possible through the generosity of Mr. Olin Moore Millican (1904-1999), who established the Roy McLeod Millican Memorial Fund in honor of his brother.
The talks typically take place on Mondays from 4:00 to 5:00 pm in GAB 461. The talks are intended for a general audience, and everyone is encouraged to attend (including undergraduates). Refreshments are served 30 minutes before the talk in the same room as the talk.
For more information, contact Lea Beneish.
Upcoming Events
September 29, 2025: Yingda Cheng (Virginia Tech)Title: Low-Rank Anderson AccelerationAbstract: In this talk, we present the low rank Anderson Acceleration (lrAA), a numerical method that directly computes low rank solutions to nonlinear equations. In many applications (e.g. nonlinear diffusion), the approximate solution, when represented as a matrix, is approximately low rank. It is challenging to design a numerical scheme for nonlinear equations that work directly with low rank. A principal challenge is that if nonlinearities are evaluated element-wise for all matrix elements then the computational savings, from quadratic to linear in the grid points per dimension, is lost. We propose lrAA, which is based on Anderson Acceleration (AA), a well known technique for accelerating Picard iteration for fixed point problems. We couple AA with low rank truncation and cross approximations. We develop a new method for matrix cross approximation, Cross-DEIM, that uses the discrete empirical interpolation method (DEIM) based index selection to achieve effective cross approximations throughout the iterations. We show that lrAA works well for benchmark problems, such as Bratu problem and Allen-Cahn equations. This is joint work with Daniel Appelö (VT). |
October 20, 2025: Joseph Vandehey (University of Texas, Tyler)Title: Creating randomness in an orderly fashionAbstract:Take the positive integers in order and concatenate them after the decimal point. The resulting number $0.1234567891011121314\cdots$ is known as Champernowne's constant. Despite being built in such a simple, mechanical way, this constant satisfies a simple test for randomness: all finite sequences of digits appear as often in Champernowne's constant as they do in the typical randomly chosen real number. One reason for this surprising result is that decimal expansions are quite nice digitally.
Every digit is as likely to occur as any other digit. Do such simple, mechanical constructions
for randomness occur if we alter the expected frequencies of the digits? We will showcase
some results showing that the answer is yes in many cases, as well as a new result
for Bernoulli shifts of finite entropy.
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November 17, 2025: Brendon Rhoades (University of California, San Diego)Title: Increasing Subsequences, Matrix Loci, and Shadow playAbstract: An increasing subsequence in a permutation $w = [w(1), \dots, w(n)]$ is a sequence $1 \leq i_1 < \cdots < i_k \leq n$ such that $w(i_1) < \cdots < w(i_k)$. Increasing subsequences in permutations play important roles in representation theory and probability. We describe a graded ring whose algebraic structure is governed by the combinatorics of increasing subsequences through the shadow line construction of X. Viennot. This ring will come from the set of $n \times n$ permutation matrices, thought of as points in matrix space. |
February 2, 2026: TBDTitle: TBDAbstract: TBD |
March 16, 2026: David Zureick-Brown (Amherst College)Title: Beyond Fermat's Last TheoremAbstract: What do we (number theorists) do with ourselves now that Fermat's last theorem (FLT) has fallen? I’ll discuss numerous generalizations of FLT -- for instance, for fixed integers $a,b,c \geq 2$ satisfying $1/a + 1/b + 1/c < 1$, Darmon and Granville proved the single generalized Fermat equation $x^a + y^b = z^c$ has only finitely many coprime integer solutions. Conjecturally something stronger is true: for $a,b,c \geq 3$ there are no non-trivial solutions. More generally, I'll discuss my subfield ``arithmetic geometry", and in particular the geometric intuitions that underlie the conjectural framework of modern number theory. |
April 6, 2026: Cris Poor (Fordham University)Title: TBDAbstract: TBD |
Recent Events
| Date | Speaker | Title |
| 2025-4-28 | Parimala, Emory University | Quadratic Forms from Arithmetic to Geometry |
| 2025-4-14 | Omer Ben-Neria, Einstein Institute of Mathematics, the Hebrew University | In Search of Stronger Axioms |
| 2025-4-7 | Weihua Geng, Southern Methodist University | Numerical methods and machine learning for the studies of biomolecular electrostatic interactions |
| 2025-3-31 | Yuan Liu, Wichita State University | Sparse grid discontinuous Galerkin methods for time dependent PDEs |
| 2025-3-17 | Sheng Xu, Southern Methodist University | The immersed interface method for flows around moving rigid objects |
| 2025-3-3 | Farbod Shokrieh, University of Washington | Graphs in algebraic and arithmetic geometry |
| 2025-2-17 | Marianna Csörnyei, University of Chicago | Embeddings into Euclidean spaces without shrinking |
| 2025-1-13 | Valentin Ovsienko, University of Champagne-Ardennes | Quantum numbers? Surely you're joking, Mr. Feynman! |
| 2024-11-18 | Martin Raum, Chalmers University of Technology | From Black Hole Mergers to Paramodular Forms |
| 2024-11-11 | Larry Rolen, Vanderbilt University | L-functions for Harmonic Maass Forms |
| 2024-11-4 | Jiahui Chen, University of Arkansas | Integrating differential operators and deep learning in biology application |
| 2024-10-14 | Ken Ribet, University of California Berkeley | Why Fibonacci's Book of squares makes us dream of cubic curves |
| 2024-10-7 | Padi Fuster Aguilera, University of Colorado Boulder | Modelling the world through an analyst lens |
| 2024-9-23 |
Maurice Rojas, Texas A&M University |
Prime Powers and Locating Roots of Equations |
| 2024-9-16 | Henri Darmon, McGill University | Unique factorization domains, elliptic curves, and modular forms |
| 2024-4-22 | Sue Sierra, University of Edinburgh | Enveloping algebras of infinite-dimensional Lie algebras |
| 2024-4-15 | Dinakar Ramakrishnan, Caltech | An invitation to Diophantine equations, congruence numbers and beyond |
| 2024-4-10 | Hannah Larson, UC Berkeley | Moduli spaces of curves |
| 2024-3-18 | Sohail Farhangi, Adam Mickiewicz University | Uniform pointwise ergodic theorems via ultraproducts |
| 2024-3-4 | Xinfeng Liu, University of South Carolina | Data-driven mathematical modeling, computation and experimental investigation of dynamical heterogeneity in breast cancer |
| 2023-11-13 | Shuang Liu, UNT | Computational moving boundary problems |
| 2023-10-23 | Wesley Perkins, Lyon College | Modulational and subharmonic dynamics of periodic waves |
| 2023-10-9 | Natasha Sharma, UT El Paso | Unconditional energy stability and solvability for a co-interior penalty method for a sixth-order Cahn-Hilliard type equation modeling microemulsions |
| 2023-9-18 | Tamara Kucherenko, CUNY | Ergodic theory on coded shifts |
| 2023-9-6 | Paco Villaroya, Santa Clara University | A characterization of compactness for singular integral operators |