Time mentioned in the table is in KST (GMT +9).


1/17 (Mon)

10:30 - 11:30   Sangjin Lee I

14:00 - 15:00   Yuto Yamamoto I

15:30 - 16:30   Junwu Tu I


1/18 (Tue)

10:30 - 11:30   Junwu Tu II

14:00 - 15:00   Yuto Yamamoto II

15:30 - 16:30   Sangjin Lee II


1/19 (Wed)

10:30 - 11:30   Junwu Tu III

14:00 - 15:00   Yuto Yamamoto III

15:30 - 16:30   Sangjin Lee III





  • Speaker:   Junwu Tu (ShanghaiTech University)
  • Title & Abstract:

1. Invariants of Calabi-Yau A-infinity categories, I

In this talk, we consider non-commutative Hodge structures associated with A-infinity categories. We also consider its variational structures known  as VSHS, variation of semi-infinite Hodge structures. The study of VSHS's generalizes classical Hodge theory to the categorical setting, and it is also related to genus zero Gromov-Witten invariants in view of mirror symmetry.


2. Invariants of Calabi-Yau A-infinity categories, II

We shall review Costello’s definition of Gromov-Witten type invariants in all genus associated with Calabi-Yau A-infinity categories. Then we write down an explicit formula of these invariants in terms of certain stable graphs whose vertices are decorated by ribbon graphs. This is mainly joint works with Andrei Caldararu.


3. Invariants of Calabi-Yau A-infinity categories, III

We give a survey of known calculations of CEI (categorical enumerative invariants). We also report on some of the recent progresses (joint works with Lino Amorim, and Yefeng Shen) in this direction.



  • Speaker:   Yuto Yamamoto (CGP-IBS) 
  • Title: Tropical spaces and their invariants
  • Abstract:

There are two types of spaces (tropical spaces) which we study in tropical geometry. One is tropical varieties which appear as tropicalizations of algebraic varieties over valued fields. They are polyhedral complexes equipped with some kind of affine structures. The other one is integral affine manifolds with singularities which arise as dual intersection complexes of toric degenerations in the Gross--Siebert program. They are also expected to be base spaces of Lagrangian torus fibrations in SYZ conjecture, and Gromov--Hausdorff limits of maximally degenerating families of Calabi--Yau manifolds with Ricci-flat Kähler metrics. In the talks, we discuss relations between these two different types of tropical spaces, and their invariants such as tropical cohomology groups.



  • Speaker:   Sangjin Lee (CGP-IBS)
  • Title: Wrapped Fukaya categories of plumbings
  • Abstract:

In these talks, we discuss how to compute wrapped Fukaya categories of plumbing spaces. More precisely, we will introduce the notion of cylinder objects and the plumbing sectors. Together with the result of Ganatra-Pardon-Shende, the above two lead us to wrapped Fukaya categories of plumbing spaces. These are based on joint works (in progress) with Dogancan Karabas.