Geometry and Topology Seminar 2019-2020
Fall 2010
The seminar will be held in room B901 of Van Vleck Hall on Fridays from 1:20pm - 2:10pm
date | speaker | title | host(s) |
---|---|---|---|
September 10 | Yong-Geun Oh (UW Madison) |
Counting embedded curves in Calabi-Yau threefolds and Gopakumar-Vafa invariants |
local |
September 17 | Leva Buhovsky (U of Chicago) | Yong-Geun | |
September 24 | Leonid Polterovich (Tel Aviv U and U of Chicago) | Yong-Geun | |
October 22 | Markus Banagl (U. Heidelberg) | Maxim | |
November 5 | Sergei Tabachnikov (Penn State) | Gloria |
Abstracts
Yong-Geun Oh (UW Madison)
Counting embedded curves in Calabi-Yau threefolds and Gopakumar-Vafa invariants
Gopakumar-Vafa BPS invariant is some integer counting invariant of the cohomology of D-brane moduli spaces in string theory. In relation to the Gromov-Witten theory, it is expected that the invariant would coincide with the `number' of embedded (pseudo)holomorphic curves (Gopakumar-Vafa conjecture). In this talk, we will explain the speaker's recent result that the latter integer invariants can be defined for a generic choice of compatible almost complex structures. We will also discuss the corresponding wall-crossing phenomena and some open questions towards a complete solution to the Gopakumar-Vafa conjecture.
Leva Buhovsky (U of Chicago)
On the uniqueness of Hofer's geometry
In this talk we address the question whether Hofer's metric is unique among the Finsler-type bi-invariant metrics on the group of Hamiltonian diffeomorphisms. The talk is based on a recent joint work with Yaron Ostrover.
Leonid Polterovich (Tel Aviv U and U of Chicago)
Poisson brackets and symplectic invariants
Markus Banagl (U. Heidelberg)
TBA
Sergei Tabachnikov (Penn State)
TBA