Patrick Lei

Seminar on K-theoretic computations in enumerative geometry (Spring 2025)
About this seminar

Enumerative geometry is a field where in many cases, the answer to a question is an actual formula. In this informal seminar, we will teach each other our tricks for actually computing these formulae. In the process, we will hopefully gain a better understanding of the underlying theory in the field.

Rules
Schedule
1/22
Organizational meeting
1/29
Konstantin Aleshkin (IPMU)
Quasimap central charges for GLSM and Fourier transforms
Mathematically, a Gauge Linear Sigma Model is a curve counting theory associated to a critical locus of a holomorphic function on a GIT quotient of a vector space. Quasimap central charges are generating functions of certain quasimap invariants related to I-functions or vertex functions or hemisphere partition functions in different contexts. I plan to explain how to compute these objects and perform variations of GIT quotient generalizing earlier results for abelian Calabi-Yau GLSM. The talk is based on a joint work in progress with Melissa Liu.
2/05
Patrick Lei
Some aspects of genus-zero mirror symmetry
I will describe some interesting properties of the I-function of the (formal) quintic threefold which are useful in understanding genus-zero mirror symmetry.
Reference: Zagier-Zinger
2/12
No seminar
2/19
Hechen Hu
TBA