Date Event Type Event Name Abstract
04/25/2017 Number Theory Seminar On the Smallest Height of Abelian Totally p-adic Numbers Given a degree d and a rational prime p, we search for the smallest non-trivial height of a totally p-adic number of degree d. If d = 2, then the smallest height depends on the congruence of p mod 5. If d = 3, then instead of a congruence condition on p, we have an algorithm which can find the...
04/24/2017 Colloquium Some 4-dimensional questions in 3-dimensional topology. In the first three quarters of the talk we will introduce several 4-dimensional questions about knots in 3-space. In the last quarter we will discuss some recent strategies for solving such questions, coming from abstract algebra and partial differential equations. Most of the talk should be...
04/24/2017 Geometry-Topology Seminar Refinements of the Jones polynomial After recalling the Jones polynomial of a knot, we will sketch the definition of two refinements: Khovanov homology and a Khovanov stable homotopy type. We will then discuss briefly how, following ideas of Lee, Ozsvath-Szabo, and Rasmussen, these can be used to obtain results about surfaces in 4-...
04/24/2017 Analysis Seminar Compact Nonlinear Semigroups This expository talk focuses on the interplay between the properties of a monotone operator, the compactness of resolvents and the equicontinuity of semigroups. Some extra attention is paid to the case that the monotone operator is the derivative of a convex function.
04/21/2017 Applied Mathematics and Computation Seminar Using Bayesian Optimization to Tune Computational Models Bio: Scott is a co-founder and CEO of SigOpt, providing optimization tools as a service, helping experts optimally tune their machine learning models. Scott has been applying optimal learning techniques in industry and academia for years, from bioinformatics to production advertising systems...
04/19/2017 Mathematical Biology Seminar Explorations in the bio-fluid-mechanics of locomotion
04/18/2017 Number Theory Seminar The mock modularity of a partition function of Andrews, Dixit, Schultz, and Yee Recently Andrews, Dixit, and Yee introduced smallest parts partition functions associated to the classical third order mock theta functions. One of these mock theta functions is $\omega(q)$. Shortly afterward Andrews, Dixit, Schultz, and Yee considered the overpartition analog of the smallest parts...
04/18/2017 Probability Seminar Coalescence and minimal spanning trees of irregular graphs We devise a method of finding the limiting mean length of a minimal spanning tree for a random graph via the Smoluchowski coagulation equations for the corresponding coalescent process. In particular, we use this approach for finding the limiting mean length of a minimal spanning tree for the Erdos...
04/17/2017 Geometry-Topology Seminar Minimal hypersurfaces with free boundary and psc-bordism There is a well-known technique due to Schoen-Yau from the late 70s which uses (stable) minimal hypersurfaces to determine whether or not a (closed) manifold supports a Riemannian metric with positive scalar curvature. In this talk, we describe a version of this technique for manifolds with...
04/17/2017 Analysis Seminar Vortex filaments and regularity of the 3D Navier-Stokes equations: Part II In this part we will discuss an approach to the NSE regularity problem based on the idea of anisotropic dissipation through of vortex filaments.
04/14/2017 Applied Mathematics and Computation Seminar Accelerating PDE Simulation with Compact Batched BLAS/LAPACK Many high-performance computing applications rely on the application of basic linear algebra operations to large groups of very small matrices. To address this need, in recent years the computational linear algebra community has developed batched BLAS (Basic Linear Algebra Subroutine) routines...
04/12/2017 Mathematical Biology Seminar Further results on partial migration We continue our analysis of evolutionary models aimed at explaining partial migration, the phenomenon where some individuals in a population migrate between breeding seasons, but others do not. Whereas we showed before that partial migration can be caused by negative density dependence alone, we...
04/11/2017 Number Theory Seminar An introduction to p-adic electrostatics We consider the distribution of N p-adic particles with interaction energy proportional to the log of the p-adic distance between two particles. When the particles are constrained to the ring of integers of a local field, the distribution of particles is proportional to a power of the p-adic...
04/10/2017 Analysis Seminar Vortex filaments and regularity of the 3D Navier-Stokes equations I will talk about a measure-type regularity criterion by Z. Grujic and discuss what it can tell about the ways to bridge the gap between the a priori bounds and critical nature of Navier-Stokes regularity problem.
04/07/2017 Applied Mathematics and Computation Seminar Spectral Clustering for Dynamic Block Models One of the most common and crucial aspects of many network data sets is the dependence of network link structure on time. In this work, we consider the problem of finding a common clustering structure in time-varying networks. We also propose an extension of the static version of nonparametric...
04/06/2017 Colloquium Viruses and Geometry: New Insights into Virus structure, Assembly and Evolutions (Joint Colloquium with Integrative Biology) PLEASE NOTE THE UNUSUAL DAY/TIME. Viruses are remarkable examples of order at the nano-scale. Many viruses, including the common cold, package their genomes into protein containers that are organized according to icosahedral surface lattices. We present here group and graph theoretical approaches...
04/05/2017 Seminar Graduate Program of Study
04/04/2017 Number Theory Seminar A number theoretic invariant of maps of surfaces Identifying opposite sides of a square yields a torus. Doing this for a regular octagon or other appropriate polygonal shapes in the plane, yields higher genus flat" surfaces. The most interesting class in Thurston's classification of homeomorphisms of surfaces are called pseudo-Anosov, or simply...
04/03/2017 Geometry-Topology Seminar Alternatives to Asphericity Continuation: Consider a relative two-complex (L,K) where K is an aspherical CW complex (of arbitrary dimension). The pair (L,K) is said to be “aspherical" if the second relative homotopy group of the pair (L,K) is trivial. In this talk, I will consider the alternatives to asphericity, examining in...
04/03/2017 Analysis Seminar Organizational Meeting