**2022년 9월 QSMS Monthly Seminar**

**Date:**30 Sep (Fri) PM 2:00 ~ 5:00**Place:**129-101 (SNU)**Contents:**

**Speaker: 조윤형 (SKKU)
Title: Monotone Lagrangians via toric degenerations: algebraic approach**

**Abstract**:

A recent work by Galkin and Mikhalkin asserts that different Q-Gorenstein toric degenerations of a monotone symplectic manifold produce different monotone Lagrangian tori. This result highly generalizes the result of Vianna in the case of the projective plane. In this talk, we review the idea of the proof and discuss an application to mirror symmetry.

**Speaker: 최학호 (QSMS, SNU)**

**Title: On symplectic fillings of Seifert 3-manifolds**

**Abstract**:

One way to understand the topology of symplectic manifolds is to study techniques for constructing symplectic manifolds. When we try to get a new symplectic manifold by gluing together local pieces, the symplectic structure on each piece should be compatible with each other along the pasting region. This search for symplectic cut-and-paste techniques has led us to the study of symplectic 4-manifolds with convex boundaries, which we call symplectic fillings.

In this talk, we discuss the symplectic fillings of a Seifert 3-manifold $Y$ with a canonical contact structure. After a brief review of the classification scheme for symplectic fillings of $Y$, I’ll explain surgery descriptions of the fillings together with relations between the fillings and Milnor fibers of the normal complex surface singularity corresponding to $Y$.