CANCELLED
- Series
- Algebra Seminar
- Time
- Monday, November 24, 2025 - 13:00 for 1 hour (actually 50 minutes)
- Location
- Skiles 005
- Speaker
- Harold Blum – Georgia Tech
Let $LC_n$ be the length of the longest common subsequences of two independent random words whose letters are taken
in a finite alphabet and when the alphabet is totally ordered, let $LCI_n$ be the length of the longest common and increasing subsequences of the words. Results on the asymptotic means, variances and limiting laws of these well known random objects will be described and compared.
Please Note: Virtual link: https://gtri.webex.com/gtri/j.php?MTID=m011cc2568fe8370921b1458aa0d5a96c
This thesis introduces a modular framework written in Macaulay2 designed to solve nonlinear algebra problems. First, we will introduce the background for the framework, covering gates, circuits, and straight-line programs, and then we will define the gates used in the framework. The remainder of the talk will include well-known algorithms such as Newton's method and Runge-Kutta for solving nonlinear algebra problems, their implementation in the framework, and explicit conic problems with a comparison between different methods.
The Mockenhaupt-Mitsis-Bak-Seeger Fourier restriction theorem extends the classical restriction theorem for measures on smooth manifolds to fractal measures. We prove the optimality of the exponent in the Mockenhaupt-Mitsis-Bak-Seeger Fourier restriction theorem in all dimensions. The proof uses number fields to construct fractal measures in R^d. This work is joint with Robert Fraser and Kyle Hambrook.
Abstract TBA
In this talk we present a perturbative proof of the asymptotic stability of the solitary wave solutions for the 1D focusing cubic Schrödinger equation under small perturbations in weighted Sobolev spaces. The strategy of our proof is based on the space-time resonances approach based on the distorted Fourier transform and modulation techniques to capture the asymptotic behavior of the solution. A major difficulty throughout the nonlinear analysis is the slow local decay of the radiation term caused by the threshold resonances in the spectrum of the linearized operator around the solitary wave. The presence of favorable null structures in the quadratic terms mitigates this problem through the use of normal form transformations.
Please Note: TBA
TBA
The permutation removal lemma was first proved by Klimosová and Král’, and later reproved by Fox and Wei in the context of permutation property testing. In this talk, we study a local version of the permutation removal problem. We show that for any permutation σ not equal to 12, 21, 132, 231, 213, or 312, there exists ε(σ) > 0 such that for any sufficiently large integer N, there is a permutation π of length N that is ε-far from being σ-free with respect to the ρ∞ distance, yet contains only a single copy of σ. Here, the ρ∞ distance is defined as an L∞-variant of the Earth Mover’s Distance between two permutations. We will also discuss our result on the local induced graph removal problem. This is joint work with Fan Wei.
In this talk, I will show how tools from VC-dimension theory can be used to address questions from incidence geometry, enumerating intersection graphs, and graph drawing.