Events
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Carlos M. Ortiz Marrer, Pacific Northwest National Laboratory/ NCSU, Non-Local Games on Graphs
ZoomIn a non-local game, two non-communicating players cooperate to convince a referee about a strategy that does not violate the rules of the game. A quantum strategy for such a game enable players to determine their answers by performing joint measurements on a shared entangled state. In this talk we will concentrate on non-local games…
Michael Merritt, NC State, Efficient Global Sensitivity Analysis for Rare Event Simulation
ZoomBy their very nature, rare event probabilities are expensive to compute; they are also delicate to estimate as their value strongly depends on distributional assumptions on the model parameters. Hence, understanding the sensitivity of the computed rare event probabilities to the hyperparameters that define the distribution law of the model parameters is crucial. We show…
Dan Lucas, Keele University, Stabilisation of exact coherent structures by time-delay feedback
ZoomTime-delayed feedback control, attributed to Pyragas (1992 Phys. Lett. 170), is a method known to stabilise periodic orbits in low dimensional chaotic dynamical systems. A system of the form dx/dt=f(x) has an additional term G(x(t)-x(t-T)) introduced where G is some 'gain matrix' and T a time delay. This form of the delay term is such…
Christian Seis, University of Münster, German, Leading order asymptotics for fast diffusion on bounded domains
ZoomOn a smooth bounded Euclidean domain, Sobolev-subcritical fast diffusion with vanishing boundary trace leads to finite-time extinction, with a vanishing profile selected by the initial datum. In rescaled variables, we quantify the rate of convergence to this profile uniformly in relative error, showing the rate is either exponentially fast (with a rate constant predicted by…
Mental Health and Neurodivergence
ZoomAMS is hosting a workshop on Mental Health and Neurodivergence next Friday, October 22, 1:55-2:45pm. During the workshop, someone from the Counseling Center will give a presentation on diagnoses and disorders that are common among graduate students. They'll cover common symptoms, treatments, as well as if/how students with the diagnoses can be supported by the university, both within…
Peter McGrath, NC State, Calculus of Variations and the Bending Energy of Surfaces
SAS 1102Beginning with the solution of the classical Plateau problem—the problem of finding an area-minimizing disk whose boundary is a prescribed simple closed curve in Euclidean 3-space—we will survey some applications of Calculus of Variations to solve geometric extremal problems. Particular emphasis will be placed on the problem of finding a smooth surface in 3-space with…
Steven Karp, Université du Québec à Montréal, Wronskians, total positivity, and real Schubert calculus
SAS 4201The totally positive flag variety is the subset of the complete flag variety Fl(n) where all Plücker coordinates are positive. By viewing a complete flag as a sequence of subspaces of polynomials of degree at most n-1, we can associate a sequence of Wronskian polynomials to it. I will present a new characterization of the…
Tim Reid, Prior Distributions for the Bayesian Conjugate Gradient Method
SAS 1108Many computational problems depend on solving systems of linear equations. The Conjugate Gradient method (CG) is a widely used iterative method that solves systems of linear equations. Early termination of CG sacrifices accuracy to save computational resources. The Bayesian Conjugate Gradient method (BayesCG) is a probabilistic generalization of CG that solves systems of linear equations…
Daniel Massatt, University of Chicago, Electronics of Relaxed Bilayer 2D Heterostructures in Momentum Space
ZoomIncommensurate stacked 2D materials have gained significant attention after the recent discovery of a new mechanism of superconductivity in systems with small twist angles. Theoretically, the electronics of such systems are studied through tight-binding models. These models can be studied in several different spaces, though momentum space is often the leading favorite for physicists because…
First Year Research Seminar by Andy Sageman-Furnas and Fatma Terzioglu
Poe Hall 320Presentations by: Andy Sageman-Furnas and Fatma Terzioglu During each 50-minute First Year Research Seminar, two faculty give our new graduate students a short (~20-25 minute), accessible talk about their research or research area
David Wiygul, ETH Zurich, Mass estimates for static vacuum metrics with small Bartnik data
ZoomIn general relativity, in the absence of special symmetries, there is no reasonable, nontrivial notion of mass-energy density accounting not only for all source fields but also for gravity itself. Nevertheless there are good definitions, such as the ADM mass, of the mass of an entire isolated system, modelled as an asymptotically flat space-time. Numerous…
Radu Ioan Boţ, University of Vienna Oskar-Morgenstern-Platz 1, Austria, Primal-dual dynamical approaches to structured convex minimization problems
ZoomIn this talk, we first propose a primal-dual dynamical approach to the minimization of a structured convex function consisting of a smooth term, a nonsmooth term, and the composition of another nonsmooth term with a linear continuous operator. To this end we introduce a dynamical system for which we prove that its trajectories asymptotically converge…
What are PTP and TCC?
ZoomAre you interested in continuing in academia after you finish your degree? You should consider the Preparing the Professoriate program and/or the Teaching and Communications Certificate offered by NCSU! This week in the Graduate Training Module, GIST is excited to host Vanessa Doriott Anderson, Director of the Teaching and Communication Programs and Organizer of the Preparing…
Learning LaTeX Tutorial
ZoomAre you an undergraduate that has heard of LaTeX, but don't know how to use it? This event is for you! LaTeX is the typesetting software used by the majority of mathematicians (and several other fields) for everything from CV's, to research papers to exams. If you plan on continuing in academia, it is almost necessary…
AMS/MGSA Trivia Night
ZoomThe AMS Student Chapter and MGSA are co-hosting a Trivia Night for graduate students on Friday, October 29, 5-6:30pm. Free pizza, chips, and soda will be provided in the 4th floor lounge. We'll form teams based on MentoRings as possible, though you do not need to be in a MentoRing (or have a team already formed)…
Michael Redle, NC State, Well-Balanced Scheme for the Shallow Water MHD Equations with a New Divergence-Free Treatment of the Magnetic Field
ZoomWe consider the shallow water magnetohydrodynamic (SWMHD) equations, in which multiscale phenomena appear in geophysics, astrophysics, and energy production applications. However, capturing both large and small scales numerically requires an exact treatment of the physically-observed divergence-free condition of the magnetic field and typically a very fine spatial grid. An alternative to requiring a fine spatial…
Ailana Fraser, University of British Columbia, Geometries That Optimize Eigenvalues
ZoomWhen we choose a metric on a manifold we determine the spectrum of the Laplace operator. Thus an eigenvalue may be considered as a functional on the space of metrics. For example the first eigenvalue would be the fundamental vibrational frequency. In some cases the normalized eigenvalues are bounded independent of the metric. In such cases…
Dave Shirokoff, New Jersey Institute of Technology, Implicit-Explicit (IMEX) Stability and Applications to the Dispersive Shallow Water Equations
ZoomIn this talk we will introduce a new stability theory for implicit-explicit (IMEX) time integration schemes—which treat some terms in a differential equation implicitly (for stability) and others explicitly (for efficiency). Our focus will be on devising new efficient stable schemes for several fluid equations ranging from the incompressible Navier-Stokes equations, nonlinear diffusion equations, and…
Peter Olver, University of Minnesota Reconstruction and signatures of 3D bodies
ZoomThe talk will begin with the reconstruction of three-dimensional bodies from their two-dimensional projections. Then I analyze the induced action of the Euclidean group on the body's projected outlines using moving frames, leading to a complete classification of the outline differential invariants and the associated outline signature of the body. Zoom invitation is sent to…