MenuEvents for 09/17/2021 from all calendars
Mathematical Physics and Harmonic Analysis Seminar
Time: 1:50PM - 2:50PM
Location: Zoom
Speaker: Daniele Mortari, TAMU
Title: The Theory of Functional Connections
Abstract: This lecture summarizes what the Theory of Functional Connections (TFC) is and presents the most important applications to date. The TFC performs linear functional interpolation. This allows to derive analytical expressions with embedded constraints, expressions describing all possible functions satisfying a set of constraints. These expressions are derived for a wide class of constraints, including points and derivatives constraints, relative constraints, linear combination of constraints, component constraints, and integral constraints. An immediate impact of TFC is on constrained optimization problems as the whole search space is reduced to just the space of solutions fully satisfying the constraints. This way a large set of constrained optimization problems can be transformed in unconstrained problems, allowing more simple, fast, reliable, and accurate methods to solve them. For instance, TFC allows to obtain fast and machine-error accurate solutions of linear and nonlinear ordinary differential equations. TFC has been extended to n-dimensions (Multivariate TFC). This allows to derive numerical methods to solve partial and stochastic differential equations. This lecture also provides some other TFC applications as, for instance, to homotopy continuation, calculus of variation, nonlinear programming, and optimal control (energy-efficient optimal landing on large bodies). Location: Meeting id: 980 8118 3032 Passcode: mpf21 Join Zoom Meeting https://tamu.zoom.us/j/98081183032?pwd=WitENWJqWjRyWVQvU3RQZDd4Mm9sUT09
URL: Event link
Noncommutative Geometry Seminar
Time: 2:00PM - 3:00PM
Location: ZOOM
Speaker: Giles Gardam , Muenster
Title: Kaplansky’s conjectures
Abstract: The Kadison–Kaplansky conjecture states that the reduced C*-algebra of a torsion-free discrete group has no idempotents other than 0 and 1. It holds for groups satisfying the Baum–Connes conjecture. If we restrict focus to group algebras, there are stronger conjectures attributed to Kaplansky on zero divisors and units. I will discuss these conjectures and my counterexample to the unit conjecture.
URL: Event link
Algebra and Combinatorics Seminar
Time: 3:00PM - 4:00PM
Location: BLOC 302
Speaker: Chun-Hung Liu, TAMU
Title: Homomorphism counts in robustly sparse graphs
Abstract: For a fixed graph H and for arbitrarily large host graphs G, the number of homomorphisms from H to G and the number of subgraphs isomorphic to H contained in G have been extensively studied in extremal graph theory and graph limits theory when the host graphs are allowed to be dense. This talk addresses the case when the host graphs are robustly sparse and proves a general theorem that solves a number of open questions proposed since 1990s and strengthens a number of results in the literature. In particular, our result determines, up to a constant multiplicative error, the maximum number of subgraphs isomorphic to H of an n-vertex graph in any fixed class of graphs with bounded expansion, which applies to any (topological) minor-closed family and many graph classes with certain geometric properties.
Committee P & T Meeting
Time: 4:00PM - 5:00PM
Location: ZOOM
, Texas A&M University