Previous Special Year Seminar

Dec
04
2025

Special Year Research Seminar

Typical and Atypical Intersections: Geometry, Dynamics, and Applications
1:00pm|Simonyi 101

Many geometric spaces carry natural collections of special submanifolds that encode their internal symmetries. Examples include abelian varieties and their sub-abelian varieties, locally symmetric spaces with their totally geodesic subspaces, period...

Dec
03
2025

Special Year Learning Seminar

Logarithmic Geometry and Hodge Theory
Michael Barz
2:00pm|Simonyi 101

Ben Bakker explained to us how to construct moduli spaces of polarized Hodge structures, and then produced period maps associated to families of smooth projective varieties. However, in practice one often encounters a family of smooth varieties...

Nov
20
2025

Special Year Research Seminar

Introduction to Non-abelian Hodge Theory
1:00pm|Simonyi 101

The goal of these lectures is to present the fundamentals of Simpson’s correspondence, generalizing classical Hodge theory, between complex local systems and semistable Higgs bundles with vanishing Chern classes on smooth projective varieties.

Nov
19
2025

Special Year Learning Seminar

Introduction to Non-abelian Hodge Theory
2:00pm|Simonyi 101

The goal of these lectures is to present the fundamentals of Simpson’s correspondence, generalizing classical Hodge theory, between complex local systems and semistable Higgs bundles with vanishing Chern classes on smooth projective varieties.

Nov
14
2025

Special Year Research Seminar

Talk #1: On the Non-abelian Hodge Correspondence for Higher-dimensional Quasiprojective Varieties | Talk #2: Monodromy of Lagrangian Fibrations
Anh Tran and Edward Varvak
1:00pm|Simonyi 101

Speaker #1 (Tran): On a projective variety, Simpson showed that there is a homeomorphism between the moduli space of semisimple flat bundles and that of polystable Higgs bundles with vanishing Chern classes. Recently, Bakker, Brunebarbe and...

Nov
13
2025

Special Year Research Seminar

Isomonodromic Deformations of Flat Bundles and Codimension of Hodge Loci
Hank Morris
1:00pm|Simonyi 101

We give a lower bound on the codimension of a component of the non-abelian Hodge locus within a leaf of the isomonodromy foliation on the relative de Rham moduli space of flat vector bundles on an algebraic curve. The bound follows from a more...

Nov
12
2025

Special Year Learning Seminar

Intro to Hodge Theory
2:00pm|Simonyi 101

A Hodge structure is a certain linear algebraic datum.  Importantly, the cohomology groups of any smooth projective algebraic variety come equipped with Hodge structures which encode the integrals of algebraic differential forms over topological...

Nov
05
2025

Special Year Learning Seminar

Introduction to Differential Galois Theory
2:00pm|Simonyi 101

Differential Galois groups are algebraic groups that describe symmetries of some systems of differential equations. The solutions considered can live in any differential field and thus a natural framework to consider such symmetries is the setting...

Oct
30
2025

Special Year Research Seminar

Effective Computations for Weakly Special Loci
1:00pm|Simonyi 101

In this talk, I will discuss some effective computations for variations of integral Hodge structures.

Several years ago, with Ren and Javanpeykar-Kühne, I conjectured (in the Shimura setting) that a variation has only finitely many "non-factor"...

Oct
29
2025

Special Year Learning Seminar

Intro to Hodge Theory
2:00pm|Simonyi 101

A Hodge structure is a certain linear algebraic datum.  Importantly, the cohomology groups of any smooth projective algebraic variety come equipped with Hodge structures which encode the integrals of algebraic differential forms over topological...