Time and venueThe LSU Virtual Topology Seminar meets in 233 Lockett Hall, at 3:30 pm CT on Wednesdays.
BroadcastingResearchers from other institutions are welcome to participate in the virtual seminar, which is broadcast online using Viewme, a video collaboration program. If you are interested in joining us, please send an e-mail to cmmwong [at] lsu [dot] edu.
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Schedule The schedule is updated throughout the academic year, and only confirmed speakers are listed below.| Date | Speaker | Institution | Title |
|---|---|---|---|
| Oct 23, 2019 | Hung Cong Tran | University of Oklahoma | The local-to-global property for Morse quasi-geodesics |
| Oct 30, 2019 | Viet Dung Nguyen | Vietnam Academy of Science and Technology Institute of Mathematics | The higher topological complexity of the complement of fiber type arrangements and related topics |
| Nov 6, 2019 | Jason Behrstock | CUNY Graduate Center and Lehman College | Hierarchically hyperbolic groups: An introduction |
| Feb 19, 2020 | Mike Wong | Louisiana State University | Ribbon homology cobordisms |
| Mar 4, 2020 | Eva Elduque | University of Michigan | Mixed Hodge structures on Alexander modules |
| Mar 11, 2020 | Zhenkun Li | Massachusetts Institute of Technology | Decomposing sutured instanton Floer homology |
| Mitul Islam | University of Michigan | Canceled | |
| Kyle Hayden | Columbia University | Canceled |
Abstracts
Date Oct 23, 2019
Speaker Hung Cong Tran
Title The local-to-global property for Morse quasi-geodesics
Abstract We show the mapping class group, CAT(0) groups, the fundamental groups of compact 3-manifolds, and certain relatively hyperbolic groups have a local-to-global property for Morse quasi-geodesics. As a consequence, we generalize combination theorems of Gitik for quasiconvex subgroups of hyperbolic groups to the stable subgroups of these groups. In the case of the mapping class group, this gives a combination theorem for convex cocompact subgroups. This is a joint work with Jacob Russell and Davide Spriano.
Date Oct 30, 2019
Speaker Viet Dung Nguyen
Title The higher topological complexity of the complement of fiber type arrangements and related topics
Abstract In the talk we present our method to compute the higher topological complexity of the complement of fiber type arrangements. The same method will be applied to compute the higher topological complexity for some other spaces.
Date Nov 6, 2019
Speaker Jason Behrstock
Title Hierarchically hyperbolic groups: An introduction
Abstract Hierarchical hyperbolicity provides a uniform framework for working with many important examples, including mapping class groups, right angled Artin groups, Teichmuller space, and others. In this talk I'll provide an introduction to studying groups and spaces from this point of view. This talk will include joint work with M. Hagen and A. Sisto.
Date Feb 19, 2020
Speaker Mike Wong
Title Ribbon homology cobordisms
Abstract A cobordism between 3-manifolds is ribbon if it has no 3-handles. Such cobordisms arise naturally from several different topological and geometric contexts. In this talk, we describe a few obstructions to their existence, from Thurston geometries, character varieties, and instanton and Heegaard Floer homologies, and some applications. This is joint work with Aliakbar Daemi, Tye Lidman, and Shea Vela-Vick.
Date Mar 4, 2020
Speaker Eva Elduque
Title Mixed Hodge structures on Alexander modules
Abstract Given an epimorphism from the fundamental group of a smooth complex algebraic variety U onto the integers Z, one naturally obtains an infinite cyclic cover of the variety. In analogy with knot theory, the homology groups of this infinite cyclic cover, which are endowed with Z-actions by deck transformations, determine the family of Alexander modules associated to the epimorphism. In this talk, we will talk about how to equip the torsion part of the Alexander modules (with respect to the Z-actions) with canonical mixed Hodge structures in the case when the epimorphism is the induced map on fundamental groups of an algebraic map f from U into the punctured complex plane. Furthermore, we will compare the resulting mixed Hodge structure to other well studied mixed Hodge structures in the literature, including the limit mixed Hodge structure on the generic fiber of f. The relevant concepts will be introduced during the talk. Joint work with C. Geske, L. Maxim, and B. Wang.
Date Mar 11, 2020
Speaker Zhenkun Li
Title Decomposing sutured instanton Floer homology
Abstract Sutured instanton Floer homology was introduced by Kronheimer and Mrowka. In this talk I will explain how to decompose sutured instanton Floer homology with respect to a properly embedded surface inside the sutured manifold, and explain how this decomposition could be used to study the topological complexities of sutured manifolds and taut foliations. This work is partially joint with Sudipta Ghosh.