Events
Theresa Anderson, Purdue University, Dyadic analysis (virtually) meets number theory
ZoomIn this talk we discuss two ways in which dyadic analysis and number theory share a rich interaction. The first involves a complete classification of "distinct dyadic systems". These are sets of grids which allow one to compare any Euclidean ball nicely with any dyadic cube, and allow for showing that a large number of…
Jane Coons, NC State, Applications of toric geometry in algebraic statistics
ZoomChair: Seth Sullivant (smsulli2@ncsu.edu, contact for Zoom access)
Silvia Gazzola, University of Bath, Iterative regularization methods for large-scale linear inverse problems
ZoomInverse problems are ubiquitous in many areas of Science and Engineering and, once discretized, they lead to ill-conditioned linear systems, often of huge dimensions: regularization consists in replacing the original system by a nearby problem with better numerical properties, in order to find a meaningful approximation of its solution. After briefly surveying some standard regularization…
Joonas Ilmavirta, Tampere University, Finland, The light ray transform
ZoomWhen is a function in the spacetime uniquely determined by its integrals over all light rays? I will introduce the problem, discuss why we might care about it, and how one might go about proving such uniqueness results. Depending on time and audience interest, I can also discuss proofs and tensor tomography. Organizer: T.…
Rachel Minster, NC State, Randomized algorithms for tensors and matrices with applications
ZoomChair: Arvind Saibaba (asaibab@ncsu.edu, contact for Zoom access)
Jun Yan, NC State, Well-balanced numerical method for atmospheric flow equations with gravity
ZoomChair: Alina Chertock (chertock@math.ncsu.edu, contact for Zoom access)
Helen Cleaves, NC State, Global sensitivity analysis and reducing order modeling for high-dimensional systems
ZoomChair: Alen Alexanderian (alexanderian@ncsu.edu, contact for Zoom access)
Victor Magron, LAAS-CNRS, France, The quest of efficiency and certification in polynomial optimization
ZoomIn 2001, Lasserre introduced a nowadays famous hierarchy of relaxations, called the moment-sums of squares hierarchy, allowing one to obtain a converging sequence of lower bounds for the minimum of a polynomial over a compact semialgebraic set. Each lower bound is computed by solving a semidefinite program (SDP). There are two common drawbacks related to…
Samantha Kirk, NC State, How to Construct Representations of Twisted Toroidal Lie Algebras via Lattice Vertex Algebras
ZoomIf you take a simple finite-dimensional Lie algebra g and tensor it with the Laurent polynomials in one variable, then you will get an infinite-dimensional Lie algebra known as a loop algebra. Affine Lie algebras are the central extensions of such loop algebras and their representations have been of interest to several mathematicians. What happens if we tensor g with…
Mitchel Colebank, NC State, Computational modeling of patient specific pulmonary hemodynamics
ZoomChair: Mette Olufsen (msolufse@ncsu.edu, contact for Zoom access)
Carter Jameson, NC State, Data science and mathematical modeling approaches to studying collective motion
ZoomChair: Kevin Flores (kbflores@ncsu.edu, contact for Zoom access)
Lars Ruthotto, Emory University, Numerical Analysis Perspectives on Deep Neural Networks
ZoomThe resurging interest in deep learning is commonly attributed to advances in hardware and growing data sizes and less so to new algorithmic improvements. However, cutting-edge numerical methods are needed to tackle ever larger and more complex learning problems. In this talk, I will illustrate numerical analysis tools for improving the effectiveness of deep learning…
Differential Equations and Nonlinear Analysis Seminar: Roberto Cominetti, Universidad Adolfo Ibáñez, Chile, Convergence rates for Krasnoselskii-Mann fixed-point iterations
ZoomA popular method to approximate a fixed point of a non-expansive map is C is the Krasnoselskii-Mann iteration. This covers a wide range of iterative methods in convex minimization, equilibria, and beyond. In the Euclidean setting, a flexible method to obtain convergence rates for this iteration is the PEP methodology introduced by Drori and Teboulle…
Prerona Dutta, NC State, Metric entropy and nonlinear partial differential equations
ZoomChair: Tien Khai Nguyen, contact for Zoom access.
Vakhtang Putkaradze, Variational Methods for Active Porous Media
ZoomMany biological organisms are comprised of deformable porous media, with additional complexity of an embedded muscle. Using geometric variational methods, we derive the equations of motion for the dynamics of such active porous media. The use of variational methods allows to incorporate both the muscle action and incompressibility of the fluid and the elastic matrix…
Dylan Bates, NC State, Virtual reinforcement learning for balancing an inverted pendulum in real time
ZoomChair: Hien Tran (tran@ncsu.edu, contact for Zoom access)
Peter Pivovarov, University of Missouri, Stochastic functional inequalities and shadow systems
ZoomI will discuss stochastic geometry of random concave functions. In particular, I will explain how a "local" stochastic dominance underlies several functional inequalities. Emphasis will be on a notion of shadow systems for s-concave functions and their interplay with functional inequalities. Based on joint works with J. Rebollo Bueno.