Algebraic Geometry

In 1870 Jordan explained how Galois theory can be applied to problems from enumerative geometry, with the group encoding intrinsic structure of the problem. Earlier Hermite showed the equivalence of Galois groups with geometric monodromy groups, and in 1979 Harris initiated the modern study of…

Given a projective variety $X$, it is always covered by curves obtained by taking the intersection with a linear subspace. We study whether there exist curves on $X$ that have smaller numerical invariants than those of the linear slices. If $X$ is a general complete intersection of large degrees…

In this talk we will introduce new birational invariants.Many examples of obstruction to rationality and G rationality will beconsidered.

Using tropical geometry, Block-Göttsche defined polynomials with the remarkable property to interpolate between Gromov-Witten counts of complex curves and Welschinger counts of real curves in toric del Pezzo surfaces. I will describe a generalization of Block-Göttsche polynomials to…

The local volume of a Kawamata log terminal (klt) singularity is an invariant that plays a central role in the local theory of K-stability. By the stable degeneration theorem, every klt singularity has a volume preserving degeneration to a K-semistable Fano cone singularity. I will talk about a…

The main theme of the talk is the combinatorics of lattice polygons and its relationship to the geometry of the associated toric surfaces. Our point of view is to measure the complexity of lattice polygons via the complexity of geometric objects to which they give rise. For the latter, we will…

The theories of KSBA stability and K-stability furnish compact moduli spaces of general type pairs and Fano pairs respectively. However, much less is known about the moduli theory of Calabi-Yau pairs. In this talk I will present an approach to constructing a moduli space of Calabi-Yau…

Fano varieties are one of the three building blocks of algebraic varieties.In this talk, we will discuss how to describe a general n-dimensional Fano variety.Although there is no consensus on how to answer to this question, we will explore some new invariants motivated by…

Harder-Narasimhan (HN) theory gives a structure theorem for principal G bundles on a smooth projective curve. A bundle is either semistable, or it admits a canonical filtration whose associated graded bundle is semistable in a graded sense. After reviewing recent advances in extending HN theory…

I'll start by defining the Chow ring, which is an important invariant of a scheme (or stack). Next, I will define the Picard variety and Picard stack of a curve, and then introduce their universal versions $J^d_g$ and $\mathscr{J}^d_g$ over the moduli space of curves $M_g$. Recently, progress…