Search

Algebraic Geometry Algebra/Logic DeLong Diversity Functional Analysis Grad Algebra/Logic Homotopy Init Conditions Kempner Lie Theory Math Club Math Phys Noncomm Geometry Number Theory PDE/Analysis Probability Rep Theory Grad Student Seminar Thesis Defenses Topology Ulam Math Edu

Events for the weeks of March 1st – 14th

Print these events

Tue, Mar. 3 2pm (online)	Algebra/Logic Ana Belen Avilez Garcia (Chapman University) View Online:https://cuboulder.zoom.us/j/96896272260 X Cozero elements of a frame play an important role in point-free topology. The set of cozero elements, Coz L, of a frame L is a sub -frame of L (that is, a sublattice closed under countable suprema and finite infima). Moreover, the lattice Coz L join-generates the frame L if and only if L is completely regular (a result analogous to the classical one for completely regular topological spaces). Within the setting of completely regular frames, we consider the Dedekind–MacNeille completion of the lattice of cozero elements, which in this context coincides with the Bruns–Lakser construction. The frame obtained through this process turns out to be a sublocale of the original frame, specifically, the smallest sublocale containing Coz L. A central aim of the talk is to compare this sublocale with the original frame and to present results and examples showing when the two coincide and when they differ. Viewing Coz L both as a join-generating sublattice and through its completion leads naturally to two related but distinct classes of frames: cozero frames and perfectly regular frames. We will examine the relationship between these notions and provide illustrative examples. This is an ongoing joint work with Guram Bezhanishvili and Joanne Walters-Wayland. Cozero frames and perfectly regular frames
Wed, Mar. 4 2:10pm (Math350)	Math Phys Markus J. Pflaum (CU Boulder) View Online:https://cuboulder.zoom.us/j/97049173677 The theory of Heitler-London
Wed, Mar. 4 3:30pm (MATH 1…	Diversity Siddhant Agrawal, Robin Deeley, Sarah Petersen, Joseph Timmer (CU Boulder) X From adjunct positions to postdocs to faculty, there are a variety of academic jobs, and the application process for those jobs can be daunting. Join our panelists, Professors Siddhant Agrawal and Robin Deeley, Teaching Professor Joseph Timmer, and Postdoctoral Scholar Sarah Petersen, who will share their insights into navigating the academic job market. Designed for those entering the job market in the near future, this session aims to replace uncertainty with strategy and actionable guidance. Pizza will be served! Academic Job Panel
Tue, Mar. 10 1:20pm (MATH 3…	Homotopy Shauly Ragimov (University of Chicago) X I will discuss higher semi-additive character theory, a framework for (n-t)-fold characters that unifies the classical monoidal character and the transchromatic character. Roughly speaking, the goal is to study character maps from R-valued functions on a pi-finite space A to S-valued functions on the (n-t)-fold p-typical free loop space of A, in a way that is functorial not only for restriction maps but also for transfers along pi-finite spaces. A central point is that every infinity-commutative monoid admits a universal character. I will describe key structural properties of this universal character, including chromatic blue shift and higher cyclotomic descent, and I will briefly indicate how it interacts with other higher semi-additive constructions such as the semi-additive Fourier transform. For K(n)-local objects, I will describe an explicit formula for the universal character and explain how it recovers the transchromatic character for Morava E-theory. I will also discuss the natural action of GL_{n-t}(Zp) on the universal character, whose fixed points agree with rationalization when t=0. Higher semi-additive character theory
Tue, Mar. 10 1:25pm (online)	Algebra/Logic Riley Thornton (Carnegie Mellon) View Online:https://cuboulder.zoom.us/j/96896272260 X This talk is a sequel to Zoltan Vidyanszky's talk a couple weeks ago. I will explain some of the questions descriptive set theorists ask about homomorphisms between relational structures, and I will indicate the subtleties involved in adapting the algebraic approach to homomorphism problems in this context. I will also pose some purely algebraic questions that arise from this project. More on CSPs and descriptive set theory
Tue, Mar. 10 2:30pm (MATH 3…	Lie Theory Spencer Daugherty (CU Boulder) X Gessel and Zhuang introduced the concept of shuffle-compatibility of statistics on permutations of subsets of \N to describe statistics whose multiset of values on the shuffles of two disjoint permutations is determined exactly by the size and statistic values of the two permutations being shuffled. Shuffle-compatibility implies the existence of an algebraic structure on the equivalence classes induced by the statistic. For example, the descent set statistic is shuffle-compatible, and the algebra on the equivalence classes it induces is isomorphic to the Hopf algebra of quasisymmetric functions. In this talk, we generalize shuffle-compatibility to objects such as words, parking functions, and set partitions using the Hopf monoids associated with these objects. We cover a variety of well-known statistics on each object. We define various algebraic structures on the equivalence classes formed by these statistics that are, in many cases, quotients of (or isomorphic to) well-known combinatorial Hopf algebras such as FQSym, WQSym, PQSym, and NCSym. Generalizing shuffle-compatibility using Hopf monoids
Tue, Mar. 10 5pm (Math 350)	Math Club Harrison Stalvey (CU Boulder) X Take notes, outline textbooks, work out a lot of problems, visit instructor office hours—These are among answers to the question, "How do we study?" But what about the question, "How do we learn?" Specifically, what happens in our mind developmentally as we study mathematics? In this talk, we will discuss one particular learning theory that describes the learning of advanced mathematical concepts. Then we will apply the learning theory to make a cognitive model of a construction of the integers, which is a topic covered in MATH 2002, Number Systems, at CU Boulder. How Do We Learn Mathematics?
Wed, Mar. 11 4:40pm (MATH 3…	Grad Student Seminar Edouard Heitzmann X The legal standard set in Rucho v Common Cause puts the onus on the plaintiffs in a Voting Rights Act (VRA) case to demonstrate that a map is a racial rather than a partisan gerrymander in order for it to be struck down as unlawful. This means plaintiffs have to 'do the homework' of the defendants for them: they must produce a map that is at least as politically gerrymandered as the defendants drew, while achieving better racial representation outcomes. In this talk I will describe how Markov Chain Monte Carlo (MCMC) methods are typically used to solve these problems, and use this opportunity to describe the underlying mathematics. The Mathematics of Redistricting

Return to the top of the page