Skip navigation

Division of Natural Sciences & MathematicsDepartment of Mathematics



Graduate Colloquium

List of previous talks at the Graduate Colloquium:

Talks presented by students are marked by *.


May 26 Wesley Fussner
Dualized constructions in ordered algebras
May 19 Nitu Kitchloo (Johns Hopkins University)
The Stable Symplectic Category and a Conjecture of Kontsevich
May 12 Natasha Dobrinen
The big Ramsey degrees for the universal triangle-free graph
May 5 Stan Gudder
A beautiful proof
Apr 21 Miklós Rácz (Microsoft Research)
Statistical inference in networks
Apr 14 Nathan McNew (Towson University)
Two problems in number theory and probability
Feb 17 Robert Dukes
Topological Dynamics of Piecewise Lambda-Affine Maps
Nov 11 Paul Horn
The Capset Bound
Nov 4 Connor Mattes and Zachary Chaney (Colorado School of Mines
Triangular Ramsey Numbers
Oct 21 Kelley Tatangelo (Colorado School of Mines)
Multiplicativity of the Euler Characteristic
Oct 7 Michael Schraudner (Universidad de Chile)
Automorphism groups of Z-subshifts
Sep 30 Paul Horn
Analysis on Graphs


May 27 Natasha Dobrinen
An almost topological Ramsey space of strong triangle-free trees and applications to the universal triangle-free graph
May 20 Mathai Varghese (University of Adelaide)
Atiyah-Singer index theory, fractional variant and applications
May 13 Drew Ash*
My 7-Year Journey to Temporary Employment
May 6 Drew Ash*
Topological speedups (PhD defense)
Apr 29 Stan Gudder
Discrete Scalar Quantum Field Theory
Apr 22 Kirk Boyer*
Combinatorics and Geometry in Ray Sensor Networks
Apr 15 Wesley Fussner* and Allegra Reiber
Adventures in Inquiry and Self-Regulated Learning
Apr 1 Nishant Chandgotia (Brown University)
Distance between walks on graphs
Feb 18 Thomas French*
Follower, Predecessor, and Extender Set Sequences of One-Dimensional Shifts
Jan 22 Geraldo de Souza (Auburn University)
Lipschitz Spaces, Generalized Lipschitz Spaces, and their importance in analysis
Jan 15 Paul Horn
Designing designs: Keevash's proof of the Existence Conjecture
Nov 13 Aysel Erey
Counting restrained colorings of graphs
Nov 6 Dan Hathaway
Introduction to cardinal characteristics
Oct 30 Sergio Lopez-Permouth (Ohio University)
Algebras having bases that consist solely of units
Oct 23 Stephen Hartke (CU Denver)
Computational Combinatorics: Uniquely K_r-saturated Graphs
Oct 9 Ana Mamatelashvili (Auburn University)
Tukey ordering and subsets of ω1
Oct 2 Diane Ojeda (University of Toronto)
Structural Ramsey Theory
Sep 25 Math faculty
Advice to grad students: Building your portfolio and finding a job


May 29 Ghodratollah Aalipour (Kharazmi University, Iran)
Laplacian eigenvalues of graphs and simplicial complexes
May 22 Riquelmi Cardona*
The Finite Embeddability Property for some Noncommutative knotted varieties of RL and DRL
May 15 Ed Bueler (University of Alaska, Fairbanks)
Mathematical tools and obstacles in models of ice sheets
May 8 Mark Greer (University of North Alabama)
Moufang semidirect products of loops with groups and inverse property extensions
May 1 Phil DeOrsey* (CU Denver)
A Classification of Hyperfocused 12-arcs
Apr 24 Lauren Irby*
A Quick Look at Women in Mathematics
Apr 17 Jeff Boersema (Seattle University)
Real C*-algebras and real structures in graph C*-algebras
Apr 3 Michael Kinyon
Automated Deduction and Algebra
Mar 27 Allegra Reiber
Metacognition, Collaboration, and Inquiry to support self-enabled learning in mathematics
Mar 6 Nate Eldredge (University of Northern Colorado)
Geometry and probability on sub-Riemannian manifolds: taking the scenic route
Feb 27 Ronnie Pavlov
An introduction to the theory of percolation
Feb 13 Paul Horn
One day in May
Feb 6 Stan Gudder
The Universe According to Gudder
Jan 30 Konrad Aguilar*
Twisted SU(2) and Noncommutative Metric Geometry
Jan 23 Lori Alvin
Low Dimensional Dynamics: Unimodal Maps and the Quest for Homeomorphisms
Nov 14 Mei Yin
A gentle introduction to exponential random graphs
Nov 7 Adam Purcilly*
Disjunctive Rado Numbers for Two Equations of Different Forms
Oct 31 Natasha Dobrinen
Rainbow Ramsey theorems for bounded colorings of finite subgraphs of the Rado graph
Oct 24 Florian Pfender (CU Denver)
Semidefinite programming in extremal graph theory
Oct 17 Drew Ash*
Topological Speedups
Oct 10 Kate Pearce*
Where Are All the Women in Mathematics?: A Survey of History's Most Influential Women Mathematicians
Sep 26 Stan Gudder
Simple Problems, Surprising Solutions


May 30 Gabor Lippner (Harvard University)
Measurable graph theory
May 23 Sheila Miller (New York City College of Technology)
Critical sequences of rank-to-rank embeddings and a tower of finite left distributive algebras
May 16 Gavin St. John
*Goedel's theorems
May 9 Timothy Trujillo
*Thesis Defense: Topological Ramsey spaces, associated ultrafilters, and their applications to the Tukey theory of ultrafilters and Dedekind cuts of nonstandard arithmetic
May 2 Stan Gudder
The Universe According to Gudder
Apr 25 Andy Linshaw
The chiral de Rham complex
Apr 18 Gabriel Giron
*Tsirelson Type Spaces
Apr 11 Lauren Morey
*Integral enumeration formulas
Apr 4 Natasha Dobrinen
Introductory overview of the Tukey theory of ultrafilters
Feb 28 Drew Ash
*D-Simplices of Minimal Cantor Systems
Feb 21 Nathan McNew
*Things you can prove with a degree from DU, two results in number theory
Feb 14 Tim Trujillo
*Ramsey for R1 Ultrafilters and Their Dedekind Cuts: II
Feb 7 Florian Sobieczky
The Newsboy Problem
Jan 31 Riqulemi Cardona
*The Finite Embeddability Property for Noncommutative Knotted Extensions of RL
Jan 24 George Herrmann
*Lipschitz Seminorms toward Quantum Metric Spaces
Nov 8 Alvaro Arias
The Ramsey Theorem in Banach Spaces
Oct 18 Paul Horn
Probabilistic combinatorics and spectral graph theory: (not so) strange bedfellows
Oct 11 Thomas French
*Sequences of Minimal Complexity
Oct 4 Adriana Suarez
Provable Security for Key Establishment Protocols
Sep 27 Lori Alvin
Adding machines and Low Dimensional Dynamics
Sep 20 Jose Mijares
On topological Ramsey spaces


May 17 Timothy Trujillo
* Diamonds as initial structures in the Tukey hierarchy of p-points
May 10 Mark Greer
* PhD Defense, Loops and their permutation groups
Apr 26 Rick Kitchen
Interactive assessment of teaching and learning
Apr 12 Andreas Blass (Michigan)
Abelian groups that want to be free
Mar 29 Jonathan D. H. Smith (Iowa State)
Beyond groups
Mar 8 Frank Schroeck
The axioms of quantum mechanics
Nov 9 Stan Gudder
Probability problems
Nov 2 Tim Trujillo
* Higher Dimensional Ramsey Theory
Oct 26 Florian Sobieczky
The blind ant and the myopic ant in the labyrinth
Oct 19 Alvaro Arias
Operator algebras
Oct 12 Ronnie Pavlov
Undecidability and computability in symbolic dynamics
Oct 5 Zhe Liu
An introduction to operator algebras, unbounded operators, and their relations to physics
Sep 21 Dennis Pace
* Axiom of Choice: Equivalences and Applications


May 17 Christian Westhof
* The Arrival of the Truth Table
May 4 David Ellerman (University of California at Riverside)
Interpreting Quantum Mechanics: The Objective Indistinctness Vision of Quantum Reality Based on the Logic of Partitions
Apr 27 Mark Greer
* Sylow Theory for Commutative Automorphic Loops
Apr 20 Drew Ash
* Ergodic and Weak-Mixing Transformations
Apr 13 Jimmy Thorne
* A better integral
Apr 6 Rick Ball
Truncated vector lattices
Mar 9 Timothy Trujillo
* The Topological Ramsey Space H^2
Mar 2 George Herrmann
* Sequence, Nets and Moore-Smith Convergence
Feb 10 Thomas French
* Spatial Voting Theory as a Predictive Model for Elections
Jan 20 Natasha Dobrinen
The Ellentuck space and Ramsey ultrafilters
Nov 11 Drew Ash
* A word on Sarkovskii's Theorem
Nov 4 Timothy Trujillo
* Ultraproducts and Nonstandard Models of Arithmetic
Oct 28 Stan Gudder
Quantum probability theory
Oct 21 Alvaro Arias
Continuous and non-continuous linear maps in norm spaces and Banach spaces
Sep 30 Jerry Lodder (New Mexico State)
Teaching Mathematics from Historical Sources
Sep 23 Sean Cox (Muenster, Germany)
The Tree Property and elementary embeddings
Sep 16 Natasha Dobrinen
Some notions in set theory


May 20 Yaodong Xiang
* An introduction to Black-Scholes equation
May 6 Jeff Farmer
Why math is real: Three short stories
Apr 29 Kyle Pula
* Approximate transversals of latin squares (PhD defense)
Apr 22 Mark Greer
* Some varities of dissociative loops - structures and constructions
Apr 15 Nawal Alznad
* T-uniformly continuous functions on a flow
Apr 1 Frederic Latremoliere
Irreducible covariant representations of automorphic actions of finite groups on C *-algebras
Mar 25 Gabriel Giron-Garnica
* Dynkin pi-lambda theorem
Mar 11 Andrew Linshaw (Darmstadt Technical University, Germany)
Introduction to vertex algebras and some connections with classical invariant theory
Feb 11 Jan Mycielski (CU Boulder)
Set theory and Learning theory
Feb 4 Natasha Dobrinen
An overview of set theory
Jan 28 Nic Ormes
Self-inducing minimal Cantor systems
Jan 21 Petr Vojtechovsky
A mathematical result is born!
Nov 14 Timothy Trujillo
* Ultrafilter mappings and their Dedekind cuts
Nov 5 Nichole Carlson (University of Colorado Denver)
Opportunities in biostatistics
Oct 29 Jeff Farmer
Where counting comes from: Developments in research on early mathematics learning
Oct 22 Michael Kinyon
A gentle introduction to nonassociativity
Oct 15 Bart Kastermans (University of Colorado Boulder)
(Maximal) Cofinitary Groups
Oct 8 Ronnie Pavlov
Shifts of finite type and entropy in one and two dimensions
Oct 1 Kyle Pula
* Large partial transversals of small latin squares
Sep 24 Daniel Van Der Vieren
The Rubik's cube as a Vigenere-transposition cryptosystem
Sep 17 Natasha Dobrinen
Introduction to Ramsey theory


May 27 Sheila Miller (US Military Academy, West Point)
Free left distributive algebras
May 14 Nathan McNew
* Efficient realization of nonzero spectra by polynomial matrices
May 7 Brett Werner
* Strong orbit equivalence and residuality
Apr 30 Riquelmi Cardona Fuentes
* On widest empty
Apr 23 Stan Gudder
Quantum probability theory
Apr 16 Rick Ball
Reflections on reflections
Apr 9 Jim Hagler
Bases in Banach spaces
Apr 2 Nic Ormes
The conjugacy problem for shifts of finite type
Mar 5 Petr Vojtechovsky
Graphs with large girth and chromatic number
Feb 19 Man-Duen Choi (University of Toronto)
Non-commutative magic everywhere
Feb 15 Andrzej Dudek (Carnegie Mellon University)
On generalized Ramsey numbers of Erdos-Rogers and Folkman
Feb 12 Marius Ionescu (University of Connecticut)
Entropy calculations in fractal dynamical systems
Feb 8 Ronnie Pavlov (University of British Columbia)
Shifts of finite type and entropy in one and two dimensions
Feb 5 Greg Oman (Ohio University)
Jonsson modules
Jan 29 Alvaro Arias
Commutant lifting theorem
Jan 22 Ales Drapal (Charles University in Prague, Czech Republic)
Quadratic sieve
Nov 13 Frederic Latremoliere
Compact quantum metric spaces
Nov 6 Timothy Trujillo
* Ultrafilters on $\omega$
Oct 30 Michael Kinyon
Loops and 3-nets
Oct 23 Annette Locke
* Thesis defense
Oct 16 Alexander Kechris (California Institute of Technology)
The complexity of classification problems in ergodic theory
Oct 9 Clifton E. Ealy, Jr. (Western Michigan University)
On profinite loops
Oct 2 Ales Drapal (Charles University in Prague, Czech Republic)
Cryptography: The mathematics and the curriculum
Sep 25 Natasha Dobrinen
Boolean algebras
Sep 18 Katherine Thompson (University of Vienna, Austria)
Simple axioms, a labyrinth of universes


Oct 24-31 Paul Truman
Hopf Algebras In Galois Module Theory
Oct 17 Tim Trujillo
* Attractors for Nonlinear Reaction-Diffusion Equations in Unbounded Domains
Oct 9 Allegra Reiber
K-theory of categories and Bivariant theories II
Oct 2 Allegra Reiber
K-theory of categories and Bivariant theories I
Sep 26 Kyle Pula
* Transversals and their generalizations in Latin squares
Sep 19 Dan Daly
* Reduced decompositions, repetitions, and permutation patterns


May 30 Nic Ormes
Continued fractions
May 23 Annette Locke
* The Banach space HT and its characteristics
May 16 Jonathan Von Stroh
* Dilations, compressions, and the von Neumann inequality
May 9 Dan Daly
* Reduced decompositions with few repetitions and permutation patterns
May 2 Yan Mayster
* Minimax approximation of 2D points using step functions
Apr 25 Sarah Bailey Frick (Ohio State)
Ergodic invariant measures and Limited Scope adic transformations
Apr 18 Kyle Pula
* Generalizing the Hall-Paige conjecture
Apr 11 Rick Ball
Introduction to pointfree topology
Apr 4 Watching the movie "Hakase No Aishita Suushiki"
("The Professor and His Beloved Equation")
Mar 7 Mark Greer
* Turbo codes
Feb 29 Dan Daly
* Connections between reduced decompositions and permutation patterns
Feb 22 Brett Werner
* Kakutani equivalence in minimal Cantor systems
Feb 8 Aditya Nagrath
* Properties of scattered lattices and the introduction of a meet semilattice duality (thesis defense)
Feb 1 Andrew Dykstra (Colorado State)
The weak equivalence relation in symbolic dynamics
Jan 25 Astrid an Heuf (New South Wales)
C-algebras associated to transformation groups
Jan 18 Alvaro Arias
Introduction to mathematical finance
Jan 11 Deb Carney
Flatland the movie
Nov 9 Jenya Kirshtein
* On the uniqueness of the weight enumerator of a perfect code
Nov 2 Nic Ormes
Tillings: Symmetric and Asymmetric
Oct 26 Michael Kinyon
Applications of automated reasoning to problems in quasigroup theory and loop theory
Oct 19 Brett Werner
* Entropy of Shifts of Finite Type (SFT)
Oct 12 Poonam Singh
* Fixed point theorems in uniform spaces II
Oct 5 Poonam Singh
* Fixed point theorems in uniform spaces I
Sep 28 Nathan McNew
* Inductive limits of ordered groups and continued fractions
Sep 21 Sarah Campbell
Inductive limits of groups


Jun 1 Dan Daly
* Permutation pattern avoidance
May 25 Sarah Law
3Sum Hard Problems
May 11 Brett Werner
Substitution Systems (and their Entropy) to Bratteli Diagrams
May 4 Jeff Farmer (Northern Colorado)
What does a mathematician bring to teacher education?
Apr 13 Jenya Kirshtein
* Finite-difference solutions of the problem of biphase filtration in the porous medium
Apr 6 Aditya Nagrath
* The Jordan-Holder chain condition for semimodular lattices
Mar 9 Shawn O?Donoghue
* The Weierstrass approximation theorem
Mar 2 Brett Werner
* Bratteli diagrams and ordered groups
Feb 23 Sarah Law
* The ellipsoid method
Feb 16 Petr Vojtechovsky
Combinatorial problems as dynamical systems
Jan 19 Kyle Pula
* Gallai multigraphs
Jan 12 Teiko Heinonen (Turku, Finland)
Approximately repeatable measurements
Nov 17 Petr Vojtechovsky
Codes of variable length with a view toward Shannon's Noiseless Theorem
Nov 10 Shlomo Reisner (Haifa)
From regular polygons to algorithms for polytope approximation
Nov 4 Michael Kinyon
How to add vectors
Oct 27 Brett Werner
* Ordered groups of Bratteli diagrams
Oct 20 Nic Ormes
An introduction to chaos theory
Oct 13 Aditya Nagrath
* Scattered lattices II
Oct 6 Aditya Nagrath
* Scattered lattices
Sep 29 Fernando Tohme (Departamento de Economia - Universidad
Nacional del Sur, CONICET, Argentina) Formal limitations in economic theory and the alternative set theory AFA - + AD + AC
Sep 22 Jonathan Poritz (Colorado State, Pueblo)
Pure math in the news: Perelman and Poincare


May 26 Joel Cohen
Prime numbers and powers of 2: A computational perspective
May 19 Aditya Nagrath
* Representation of distributive lattices II
May 12 Kurt Koltko
A gauge theory of CPT transformations
May 5 Cy Holladay
* Queen domination
Apr 28 Oscar Hasbun
* Fast matrix multiplication II
Apr 21 Jim Hagler
Grothendieck inequality
Apr 17 Merab Gogberashvili (Andronikashvili Institute of Physics, Tbilisi, Georgia)
Octonionic geometry
Apr 14 Stan Gudder
Why quantum computers can do things ordinary computers cannot
Mar 31 Alvaro Arias
Stone-Weierstrass theorem
Mar 10 Aditya Nagrath
* Birkhoff's Theorem - Representation of distributive lattices
Mar 3 Oscar Hasbun
Fast matrix multiplication
Feb 24 Rick Ball
D5-T5 theorem
Feb 17 Mark Tomforde (William and Mary)
C*-algebras of directed graphs
Feb 10 Adriana Nenciu (Florida)
Number of character tables of finite groups
Feb 3 Michael Kinyon (Indiana U South Bend)
The Coquecigrue of a Leibniz Algebra: Recent Progress
Jan 27 Rick Ball
A little lattice theory
Jan 20 Petr Vojtechovsky
Sphere packings and lattices
Jan 6 Kyle Pula
* Mutually orthogonal Latin squares
Nov 18 Trent Hampton
On Riemann Hypothesis
Nov 11 Wojciech Kosek (Colorado College)
Dynamical methods in combinatorial number theory: history and some new results about prime numbers
Nov 4 Sarah Law
* An introduction to queuing theory
Oct 28 Tricia Winning
* Euclid's parallel postulate and the discovery of hyperbolic geometry
Oct 14 Alvaro Arias
Marriage theorem and decomposition of measures
Oct 7 Claudio Delrieux (Universidad Nacional del Sur, Argentina)
Fractal objects at the intersection of mathematics and computer science
Sep 30 Nic Ormes
Fractals : In between dimensions
Sep 23 Rick Ball
Selling pizza II
Sep 16 Rick Ball
Selling pizza


May 20 Jonathan Von Stroh
RSA cryptography and theoretical quantum implications
May 13 Giorgio Ottaviani (U Florence, Italy)
What is computational algebraic geometry?
May 6 Cy Holladay
* Knight's tours
Apr 29 Bill Cherowitzo (UC Denver)
On generalizing the concept of a conic
Apr 22 Aditya Nagrath
On downward order continuous and Priestley spaces
Apr 15 Aditya Nagrath
A dreaded counterexample
Apr 8 Alvaro Arias
Matrix inequalities
Apr 1 Stan Payne (UC Denver)
Quadratic equations over finite fields
Feb 25 Sarah Law
* Moebius maps
Feb 18 Jim Hagler
The dollar auction
Feb 11 Frank Schroeck
Feb 4 Kyle Pula
* Polya theory of counting II
Jan 21 Kyle Pula
* Polya theory of counting I
Jan 14 Dan Daly
* Designs and projective planes
Jan 7 Cy Holladay
* Logic and formality
Nov 17 Kyle Pula
* Introduction to combinatorial design theory
Nov 12 Chris Rasmussen (San Diego State University)
A brief introduction to mathematics education research and an illustrative example
Nov 5 Aditya Nagrath
* Priestley spaces II
Oct 29 Aitya Nagrath
* Priestley spaces
Oct 22 Sarah Law
* The art gallery theorem
Oct 15 Nic Ormes
Entropy and symbolic dynamics
Oct 8 Stan Gudder
Oct 1 Petr Vojtìchovský
Matrix games
Sep 24 Alvaro Arias Introduction to cryptography


May 28 Rick Ball
On Stone-Weierstrass theorem
May 21 Petr Vojtìchovský
Projective plane of order 2 and its many disguises
May 14 Aditya Nagrath
* Priestley spaces with a few accumulation points II
May 7 Aditya Nagrath
* Priestley spaces with a few accumulation points I
Apr 30 Alvaro Arias
Antisymmetric tensor products and singular values
Apr 23 Alvaro Arias
Majorization of vectors in R n and eigenvalue estimates
Apr 16 Nic Ormes
Symbolic dynamics and the spectra of nonnegative matrices
Apr 9 Stan Gudder
On Kadison's theorem
Mar 5 Brett Werner
* Introduction to discrete dynamical systems
Feb 27 Jennifer Proal
* Knots
Feb 20 Kimberly Wey
* Banach-Tarski paradox
Feb 13 Charles Holland (Bowling Green)
Divisible ordered groups: A counterexample
Feb 6 Nic Ormes
Continuous fractions
Jan 30 Jim Hagler
Approximating real numbers by rational numbers
Jan 16 Petr Vojtìchovský
Magic squares
Nov 14 Rick Ball
On well-ordered sets II
Nov 7 Mario Lopez
The power of duality
Oct 31 Rick Ball
On well-ordered sets
Oct 24 Nic Ormes
Period 3 implies chaos