Seminars and Colloquia Schedule

Weak KAM theorem for Frenkel-Kontorova models and related topics

Series
CDSNS Colloquium
Time
Monday, May 8, 2017 - 11:00 for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Xifeng Su – Beijing Normal University
We will consider the Frenkel-Kontorova models and their higher dimensional generalizations and talk about the corresponding discrete weak KAM theory. The existence of the discrete weak KAM solutions is related to the additive eigenvalue problem in ergodic optimization. In particular, I will show that the discrete weak KAM solutions converge to the weak KAM solutions of the autonomous Tonelli Hamilton-Jacobi equations as the time step goes to zero.

Concordance and Dehn surgery

Series
Geometry Topology Seminar
Time
Monday, May 8, 2017 - 14:00 for 1 hour (actually 50 minutes)
Location
Skiles 006
Speaker
Tye Lidman – NCSU
We will discuss a relation between some notions in three-dimensional topology and four-dimensional aspects of knot theory.

Working Group for Problems in Transport and Related Topics in Graphs

Series
GT-MAP Seminar
Time
Tuesday, May 9, 2017 - 10:00 for 8 hours (full day)
Location
Skiles 006
Speaker
Speaker list and schedule can be found at http://www.math.gatech.edu/hg/item/589661 – Organizers: Shui-Nee Chow, Wilfrid Gangbo, Prasad Tetali, and Haomin Zhou

This workshop is sponsored by College of Science, School of Mathematics, GT-MAP and NSF.

The goal of this workshop is to bring together experts in various aspects of optimal transport and related topics on graphs (e.g., PDE/Numerics, Computational and Analytic/Probabilistic aspects).

A fractalization process for affine skew-products on the complex plane

Series
CDSNS Colloquium
Time
Wednesday, May 10, 2017 - 13:00 for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Marc Jorba-Cusco – Universitat de Barcelona
Consider an affine skew product of the complex plane. \begin{equation}\begin{cases} \omega \mapsto \theta+\omega,\\ z \mapsto =a(\theta \mu)z+c, \end{cases}\end{equation}where $\theta \in \mathbb{T}$, $z\in \mathbb{C}$, $\omega$ is Diophantine, and $\mu$ and $c$ are real parameters. In this talk we show that, under suitable conditions, the affine skew product has an invariant curve that undergoes a fractalization process when $\mu$ goes to a critical value. The main hypothesis needed is the lack of reducibility of the system. A characterization of reducibility of linear skew-products on the complex plane is provided. We also include a linear and topological classification of these systems. Join work with: N\'uria Fagella, \`Angel Jorba and Joan Carles Tatjer