Events for 04/30/2021 from all calendars

Faculty Meeting

Time: 1:00PM - 2:00PM

Location: Zoom

Noncommutative Geometry Seminar

Time: 1:00PM - 2:00PM

Location: Zoom 951 5490 42

Speaker: Anna Skripka, University of New Mexico

Title: Approximation of functions of unbounded operators

Abstract: We will discuss recent advancements in approximation of functional calculus arising in problems of mathematical physics and noncommutative geometry. Our goal is to establish nice bounds and representations for (semi-)norms of approximation errors. Challenges arise, in particular, from noncommutativity of a perturbation and initial unbounded operator as well as noncompactness of the perturbation. Successful resolution rests on multilinear operator integration, a powerful technical method with a long history in noncommutative analysis.

URL: Event link

Geometry Seminar

Time: 4:00PM - 5:00PM

Location: Zoom

Speaker: Matthew Faust, Texas A&M University

Title: The number of critical points of dIscrete periodic operators

Abstract: The spectral gap conjecture is a well known and widely believed conjecture in mathematical physics concerning the structure of the Bloch variety (dispersion relation) of periodic operators. The Bloch variety of a discrete operator is algebraic, inviting methods from algebraic geometry to their study.

Motivated by this this conjecture, this talk will introduce a bound on the number of critical points of the dispersion relation for discrete periodic operators, and provide a general criterion for when this bound is achieved. We also present classes of periodic graphs for when this criteria is satisfied for Laplace-Beltrami operators. This is joint work with Frank Sottile.