Colloquia and Seminars

We host several regular research seminars throughout the academic year. On this page, you will find announcement for the seminars, as well as a list of past seminars. Please email the organizer of any seminar with any questions or talk requests.

Graduate Colloquium

The Graduate Colloquium is organized by Dr. Sujoy Mukherjee and Dr. Rodrigo Ribeiro.

 

11/17/2023, 2pm, CMK 309
Darren Creutz (US Naval Academy)
Actions of lattices in higher-rank semisimple Lie groups

 

Abstract: Lie groups, such as $\mathrm{SL}_{3}(\mathbb{R}$, arise in areas ranging from number theory to quantum mechanics and their discrete subgroups, lattices such as $\mathrm{SL}_{3}(\mathbb{Z})$, have long been a focus of study. Margulis, as part of what earned him a Fields Medal, proved his celebrated Normal Subgroup Theorem: all lattices in higher-rank Lie groups are almost simple in the sense that every normal subgroup is either finite or has finite index.

A natural generalization of this, conjectured by Zimmer, is that every continuous action of such a lattice on a compact metric space should be free. In a series of papers, some coauthored with J. Peterson (Vanderbilt), we established that this is indeed the case.

I will present these results and their context assuming very little background beyond standard group theory and measure theory.

  • Past Colloquia

    11/03/2023
    Dylene Agda Souza de Barros (Federal University of Uberlandia)
    Half-automorpshism of Bol loops

    10/13/2023
    Rodrigo Ribeiro (University of Denver)
    Interdisciplinary Perspectives on Network Analysis: A Confluence of Computer Science, Mathematics, and Statistics

    03/20/2022
    Nick Galatos (University of Denver)
    Dropping inverses in lattice-ordered groups

    03/11/2022
    Vidit Nanda (University of Oxford)
    Path signatures in topology, dynamics and data

    02/18/2022
    Joshua Loftus (London School of Economics)
    Fair algorithms and causal models

    02/04/2022
    John Baez (University of California, Riverside)
    Schur Functors

    01/28/2022
    David Bressoud (Macalester College)
    Calculus Reordered: A History of the Big Ideas

    11/12/2021
    Antun Milas (SUNY Albany)
    Introduction to vertex algebras from a number theoretic viewpoint

    10/28/2021
    Ronnie Pavlov (University of Denver)
    How I learned to stop worrying and love the group: some unexpected connections between symbolic dynamics and geometric group theory

    04/23/2021
    Robert Osburn (University College Dublin)
    From knots to modularity

    03/05/2021
    Victor Gurarie (University of Boulder)
    Logarithms in conformal field theories and indecomposable representations of superalgebras

    02/26/2021
    Ed Chien (Boston University)
    Applications of vector field topology in surface and volume meshing

    02/05/2021
    Ken Alexander (University of Southern California)
    Geodesics, bigeodesics, and coalescence in first passage percolation

    01/22/2021
    Zahra Aminzare (University of Iowa)
    Synchronization properties in complex networks

    11/06/2020
    Julia Plavnik (Indiana University)
    On the classification of modular categories

    10/30/2020
    Thomas French (University of Denver)
    Arrow's Theorem and Voting

    10/09/2020
    Abhijit Champanerkar (College of Staten Island and The Graduate Center at The City University of New York)
    Graphs, growth and geometry

    09/25/2020
    Farai Nyabadza (University of Johannesburg)
    Mathematical models versus reality! The case of COVID-19 modelling in South Africa

    01/24/2020
    Alejandro Ginory (Rutgers University)
    Double Affine Weyl Groups and Fusion Algebras for Affine Lie Algebras

    11/15/2019
    Yiqing Geng (University of Denver)
    Introduction to rotation theory

    11/08/2019
    Patricia Hickman (University of Denver)
    Resumes + CV’s That Get Results!

    10/25/2019
    Nick Galatos (University of Denver)
    Binary relations on partially-ordered sets

    10/18/2019
    Stan Gudder (University of Denver) Quantum Entanglement

    05/24/2019
    Piotr Hajac (CU Boulder / IMPAN)
    Operator Algebras that one can see

    05/24/2019
    George E. Andrews (Pennsylvania State University)
    The Method of 4-Shadows

    05/17/2019
    Gavin St. John (University of Denver)
    PhD Dissertation Defense: Decidability for residuated lattices and substructural logics

    05/10/2019
    Ziqin Feng (Auburn University)
    Tukey Order, Small Cardinals, and Off-diagonal Metrization

    04/26/2019
    Adam Blumenthal (Iowa State University)
    Decomposing Graphs into Edges and Triangles

    04/19/2019
    Mariusz Tobolski​ (IMPAN)
    A locally trivial talk​

    04/05/2019
    Rebecca Coulson (West Point)
    Finite constraint: A combinatorial concept with Ramsey theoretic applications

Algebra and Logic Seminar

The Algebra and Logic Seminar is organized by Dr. Charlotte Aten and Dr. Fei Qi.

11/17/2023, 9am, CMK 201
Dylene Agda Souza de Barros (Universidade Federal de Uberlândia)
Moufang Permutations

Abstract: It was shown in a recent paper by Drapal and Vojtechovsky that all split Moufang loops $Q=CX$ with $X$ an abelian group of order coprime to $3$ and $C$ a cyclic group of order coprime to $3$ are obtained from so-called Moufang permutations on $X$. We present a study of Moufang permutations on small abelian groups.

  • Past Algebra and Logic Seminars

    10/03/2023
    Layla Sorkatti (Southern Illinois University)
    Symplectic Alternating Algebras

    10/20/2023
    Charlotte Aten (University of Denver)
    Monoid representations and partitions

    10/13/2023
    Semin Yoo (Korea Institute for Advanced Study)
    Improved upper bounds for the largest size of Diophantine tuples 

    09/15/2023, 09/22/2023 and 10/06/2023
    Fei Qi (University of Denver)
    Cohomology theory of vertex algebras  (I Overview, II, Formulations, III Extensions)

    06/02/2023
    Gavin St. John (University of Salerno)
    Residuated ortholattices and orthomodular quantum logic 

    05/26/2023
    Sara Ugolini (Artificial Intelligence Research Institute of the Spanish National Research Council)
    Structural and universal completeness in quasivarieties of logic

    05/19/2023
    Shunsuke Tsuchioka (Tokyo Institute of Technology)
    A vertex operator reformulation of the Kanade-Russell conjecture modulo 9

    02/24/2022
    Jósef H. Przytycki (The George Washington University)
    From Fox coloring to Yang-Baxter homology

    02/17/2022
    Valeria de Paiva (Topos Institute)
    Dialectica Comonoids

    01/20/2023
    Uhi Rinn Suh (National Seoul University)
    Structure of classical supersymmetric (SUSY) W-algebras

    10/07/2022
    Fei Qi (University of Denver)
    Integer partitions and characters of Lie algebra representations

    09/23/2022
    Charlotte Aten (University of Denver)
    A conjecture regarding covariant derivatives of eigenfunctions along parallel tensors fields over a space form

    05/20/2022
    Jehanne Dousse (Universite de Lyon)
    Integer partitions and characters of Lie algebra representations

    04/29/2022
    Gaywalee Yamskulna (Illinois State University)
    On $\mathbb{N}$-graded vertex algebras associated with vertex algebroids that are cyclic Leibniz algebras

    02/26/2022
    Ali Uncu (University of Bath)
    Reflecting (on) the modulo 9 Kanade--Russell (conjectural) identities

    11/18/2021
    Matt Szczesny (Boston University)
    Heterotic sigma models via BV quantization and formal geometry

    11/5/2021
    Qing Wang (Xiamen University)
    The structure of parafermion vertex operator algebras

    10/28/2021
    Cuipo Jiang (Shanghai Jia Tong University)
    Varieties associated to affine vertex operator algebras $L_{k}(sl_3)$ at non-admissible levels

    10/21/2021
    Shashank Kanade (University of Denver)
    How I learned to stop being scared and love the Bailey machinery

    10/15/2021
    Jethro van Ekeren (Universidade Federal Fluminense)
    Chiral homology of elliptic curves

    >10/08/2021
    Yuly Billig (Carleton University)
    Representations of the Determinant Lie Algebra

    10/01/2021
    Xuanzhong Dai (Fudan)
    Chiral De Rham Complex on the Upper Half Plane and Modular Forms

    09/24/2021
    Josh Sussan (CUNY Medgar Evers)
    Quantum topology and categorification

    05/07/2021
    Huafeng Zhang (Université de Lille)
    Shifted Yangians and polynomial R-matrices

    11/20/2020
    Evgeny Mukhin (IUPUI)
    The evasive affine Gaudin model

    10/30/2020
    Flor Orosz Hunziker (University of Colorado, Boulder)
    Tensor Categories arising from the Virasoro algebra

    10/23/2020
    Hao Li (SUNY Albany)
    Vertex Algebras and Infinite Jet Algebras

    10/16/2020
    Kang Lu (University of Denver)
    Gaudin model, Feigin-Frenkel center, and Grassmannian

    10/9/2020
    Eric Bucher (Michigan State University)
    An introduction to cluster algebras and their applications

    01/24/2020
    Rehana Patel (African Institute for Mathematical Sciences-Senegal)
    Stable Hypergraph Regularity

    01/14/2020
    Victoria Gitman (CUNY)
    Ramsey-like cardinals

    11/08/2019
    Kaiyun Wang (Shaanxi Normal University)
    Big Ramsey degrees in universal profinite ordered k-clique free graphs

    11/01/2019
    Nick Galatos (University of Denver)
    Heyting residuated lattices

    10/18/2019 and 10/25/2019
    David Milovich (Welkin Sciences at Colorado Springs)
    Higher amalgation of algebraic structures

    05/17/2019
    David Ridout (University of Melbourne)
    Simple weight modules with finite-dimensional weight spaces

    05/10/2019
    Andrew Owens (Auburn University)
    Rainbow-Cycle-Forbidding Edge Colorings

    04/26/2019
    Kaiyun Wang
    Irreducible convergence and irreducibly order-convergence in T_0 spaces

    04/05/2019
    Tomas Prochazka (University of Munich, Arnold Sommerfeld Center for Theoretical Physics)
    W-algebras and integrability

    02/08/2019 and 02/01/2019
    Michael Kinyon (University of Denver)
    Inner Partial Automorphisms of Inverse Semigroups I, II

    01/25/2019 and 01/18/2019
    Ales Drapal (Charles University)
    Near-fields, double transitivity and quasigroups I, II

    11/16/2018 and 11/09/2018 and 11/02/20187
    Natasha Dobrinen (University of Denver)
    Introduction to infinitary Ramsey theory I, II, III

Analysis and Dynamics Seminar

The Analysis and Dynamics Seminar is organized by Dr. Mei Yin.

11/03/2023 10am, CMK 201
Anh Le (University of Denver)
Interpolation sets for dynamical systems

Abstract: Originating from harmonic analysis, interpolation sets were first studied in dynamics by Glasner and Weiss in the 80s. A set S of natural numbers is an interpolation set for a class of topological dynamical systems C if any bounded sequence on S can be extended to a sequence that arises from a system in C. In this talk, we will provide combinatorial characterizations of interpolation sets for several classes of dynamical systems: minimal systems, weak and strong mixing systems, uniquely ergodic and strictly ergodic systems. This is based on joint work with Andreas Koutsogiannis, Joel Moreira, Ronnie Pavlov and Florian Richter.

  • Past Analysis and Dynamics Seminars

    10/27/2023
    Clément Requilé (Universitat Politecnica de Catalunya)
    Asymptotic study of chordal graphs with bounded tree-width

    10/13/2023
    Clemens Heuberger (University of Klagenfurt)
    The distribution of the maximum protection number in simply generated trees

    02/25/2022
    Sumit Mukherjee (Columbia University)
    Asymptotic distribution of quadratic forms

    02/18/2022
    Zhongyang Li (University of Connecticut)
    Planar site percolation

    02/11/2022
    Amber L. Puha (California State University San Marcos)
    Scaling Limits for Shortest Remaining Processing Time Queues

    11/18/2021
    Hans Koch (University of Texas at Austin)
    Asymptotic scaling and universality for skew products with factors in SL(2,R)

    10/01/2021
    William G. Faris (University of Arizona)
    Two Theories of Integration

    09/24/2021
    Peter Hislop (University of Kentucky)
    An overview of eigenvalue statistics for random Schrödinger operators and random band matrices

    05/28/2021
    Robert Sims (University of Arizona)
    Stability of the Bulk Gap

    04/30/2021
    Hanbaek Lyu (University of California, Los Angeles)
    Scaling limit of soliton statistics of a multicolor box-ball system

    04/02/2021
    Roland Roeder (Indiana University–Purdue University Indianapolis)
    The 3 Gaps Theorem, the Boshernitzan-Dyson Theorem, frequencies, and applications

    03/19/2021
    Sabine Jansen (Ludwig-Maximilians-Universität München)
    Trees, functional inversion and the virial expansion

    02/26/2021
    Yizao Wang (University of Cincinnati)
    Limit fluctuations for density of asymmetric simple exclusion processes with open boundaries

    02/05/2021
    Christian Sadel (Pontificia Universidad Católica de Chile)
    Radial Transfer matrices for higher dimensional graphs and absolutely continuous spectrum

    01/22/2021
    AWM 50th Aniversary Lecture
    Margaret Beck (Boston University)
    Stability and counting unstable eigenvalues

    10/30/2020
    Chris Marx (Oberlin College)
    Parameter dependence of the density of states for Schrödinger operators

    10/16/2020
    Aernout van Enter (University of Groningen)
    One-sided versus two-sided stochastic processes

    09/25/2020
    Richard Kenyon (Yale University)
    Gradient variational problems

    02/07/2020
    Scott Schmieding (University of Denver)
    Automorphisms of symbolic systems

    11/08/2019 and 11/15/2019
    Stan Gudder (University of Denver)
    Naimark Dialation Theorem

    11/01/2019 and 10/25/2019
    Sara Andrade (University of Denver)
    Beyond Orthonormal bases: an introduction to finite frames I, II

    10/18/2019
    Geraldo de Souza (Auburn University)
    The special atom space, Haar System and Wavelet in higher dimensions

    09/20/2019
    Robert Niemeyer (Metro State, Denver)
    Fractal Billiard

    05/31/2019
    Javier Alejandro Chavez Dominguez (University of Oklahoma)
    Isoperimetric and Sobolev inequalities for magnetic graphs

    05/24/2019
    Piotr M. Hajac (CU Boulder / IMPAN)
    Pullbacks of graph C*-algebras from admissible intersections of graphs

    05/17/2019
    Paul Horn (University of Denver)
    Solutions to Variational Inequalities on Graphs

    05/03/2019 and 05/10/2019
    Ronnie Pavlov (University of Denver)
    Subshifts of linear complexity I, II

    04/19/2019 and 04/26/2019
    Natasha Dobrinen (University of Denver)
    Ramsey Theory on trees and applications to infinite graphs I, II

    04/12/2019
    Marco Nathan (University of Denver, Department of Philosophy)
    Mathematics, science, and philosophy

    03/01/2019
    Patrick Shipman (Colorado State)
    Counterdiffusion in Biological and Atmospheric Systems

    01/18/2019, 01/25/2019 and 02/01/2019
    Jim Hagler (University of Denver)
    An Application of Descriptive Set Theory to Banach Space Theory I, II, III

    10/26/2018
    Andrew Schnackenberg (University of Denver, Department of Management)
    Making qualitative data quantitative: An overview of content analysis

    10/19/2018
    Wen Zhou (Colorado State)
    Estimation and Inference of Heteroskedasticity Models with Latent Semiparametric Factors for Multivariate Time Series

    10/12/2018
    Valentin Deaconu (University of Nevada)
    Symmetries of Cuntz-Pimsner algebras

    09/21/2018 and 10/05/2018
    Ryan DeMuse (University of Denver)
    Exponential Random Graph Models

Inclusive Teaching Seminar

The Inclusive Teaching Seminar is organized by Dr. Sara Botelho-Andrade and Dr. Sabine Lang.

Other Seminars

The department holds various additional seminars which may not be offered regularly. Please contact the organizer(s) or follow the provided link of any seminar you wish to attend for further information.