Events for 02/28/2020 from all calendars
Several Complex Variables Seminar
Time: 10:20AM - 11:10AM
Location: BLOC 605AX
Speaker: Shreedhar Bhat, Texas A&M University
Title: Student reading seminar on reproducing kernels
Abstract: More properties of reproducing kernels
Mathematical Physics and Harmonic Analysis Seminar
Time: 11:30AM - 12:30PM
Location: BLOC 628
Speaker: Ram Band, Technion - Israel Institute of Technology
Title: Quotients of finite-dimensional operators by symmetry representations (UNUSUAL TIME)
Abstract: A finite dimensional operator which commutes with some symmetry group, admits quotient operators. Such a quotient operator is determined by the group action and by picking a certain representation of this group. We present a computationally simple construction to obtain quotients that reflect the structure of the original operators. These quotient operators allow us to generalize previous isospectral constructions of discrete graphs, as well as to provide tools for spectral analysis of finite dimensional operators.
This talk is based on a joint work with Gregory Berkolaiko, Christopher H. Joyner and Wen Liu.
Working Seminar on Quantum Computation and Quantum Information
Time: 2:00PM - 3:00PM
Location: BLOC 624
Speaker: Michael Brannan, TAMU MATH
Title: More on quasi-triangular Hopf algebras, Yang-Baxter Equations, and Kitaev's Quantum Double Model
Seminar on Banach and Metric Space Geometry
Time: 3:00PM - 4:00PM
Location: BLOC220
Speaker: Alex Andoni, Columbia University, Data Science Institute
Title: Estimating distances in a graph metric, in parallel
Abstract: We show how to estimate distances (and shortest paths) between nodes in undirected graphs using a fast parallel algorithm. Our algorithm achieves $(1+\epsilon)$ approximation, poly(log n) time and m*poly(log n) work for n-nodes m-edges graphs --- a question open since Cohen's result from STOC'94. One of our main tools is a new notion of low hop emulators: a poly(log n)-approximate emulator graph in which every shortest path has at most O(loglog n) hops (edges). Direct applications of this tool are efficient parallel constructions of Bourgain's embedding, metric tree embedding, and low diameter decomposition. To obtain the better approximation ratio, we introduce compressible preconditioners and apply it inside Sherman's framework (SODA'17) to solve the more general problem of transportation in graphs (uncapacitated minimum cost flow). As a consequence, it also improves the state-of-the-art sequential running time for the latter. Joint work with Cliff Stein, Peilin Zhong. To appear in STOC'20.
Geometry Seminar
Time: 4:00PM - 5:00PM
Location: BLOC 628
Speaker: Baris Coskunuzer, UT Dallas
Title: Minimal Surfaces in Hyperbolic 3-Manifolds
Abstract: In this talk, we will discuss the existence of smoothly embedded closed minimal surfaces in infinite volume hyperbolic 3-manifolds. The talk will be non-technical, and accessible to graduate students.
Linear Analysis Seminar
Time: 4:00PM - 5:00PM
Location: BLOC 220
Speaker: Michael Brannan, TAMU MATH
Title: Synchronous Games, Traces, and an Explicit Separation for the Tsirelson Problem, Part II
Abstract: I will continue from last week - wrapping up the construction of the game that witnesses an explicit separation for the Tsirelson problem, and I will also tr to explain a bit more how COMPRESS and the fixed point theorem are used to get the main results (addressing a question of Konrad from last week).