Previous Conferences & Workshops

Nov
06
2024

Special Year Seminar I

The Schubert Variety of a Pair of Linear Spaces
2:00pm|Simonyi 101 and Remote Access

I will motivate the study of the Schubert variety of a pair of linear spaces via Kempf collapsing of vector bundles. I'll describe equations defining this variety and how this yields a simplicial complex determined by a pair of matroids which...

Nov
05
2024

Joint IAS/PU Groups and Dynamics Seminar

Stable Invariants of Words from Random Matrices
4:30pm|314 Fine Hall

Let w be a word in a free group. A few years ago, Magee and I, relying on a work of Calegari, discovered that the stable commutator length of w, which is a well-studied topological invariant, can also be defined in terms of certain Fourier...

Nov
05
2024

Analysis and Mathematical Physics

Duality of Fluid Mechanics and Solution of Decaying Turbulence
2:30pm|Simonyi Hall 101 and Remote Access

I will describe the duality of incompressible Navier-Stokes fluid dynamics in three dimensions, leading to its reformulation in terms of a one-dimensional momentum loop equation.
The decaying turbulence is a solution of this equation equivalent to a...

Nov
05
2024

Symplectic Geometry Seminar

Plumber’s Algebra Structure on Symplectic Cohomology
1:00pm|Simonyi 101 and Remote Access

I will introduce a new structure on (relative) Symplectic Cohomology defined in terms of a PROP called the “Plumber’s PROP.” This PROP consists of nodal Riemann surfaces, of all genera and with multiple inputs and outputs, satisfying a condition...

Nov
05
2024

Computer Science/Discrete Mathematics Seminar II

Fault Tolerant Routing Protocols on High-Dimensional Expanders
Mitali Bafna
10:30am|Simonyi 101 and Remote Access

In this talk, I will elaborate on the main technical component of our PCP—the construction of routing protocols on high-dimensional expanders (HDX) that can withstand a constant fraction of edge corruptions. We consider the following routing problem...

Nov
04
2024

Joint IAS/PU Arithmetic Geometry

Etale Cohomology of Shimura Varieties via Coherent Sheaves
3:35pm|*Princeton University, Fine Hall 224*

Studying the \’etale cohomology of Shimura varieties with Hecke and Galois actions provides an avenue toward understanding the Langlands correspondence. 
While the structure of the rational cohomology groups is predicted conjectures of Kottwitz and...

Nov
04
2024

Members' Colloquium

Zeroes of Characters (cf. J.-P. Serre, same title, arXiv 2312.17551)
1:00pm|Simonyi 101 and Remote Access

A promenade in Serre's paper, plus some related results of mine.

Nov
04
2024

Computer Science/Discrete Mathematics Seminar I

Quasi-Linear Size PCPs with Small Soundness from High-Dimensional Expanders
Mitali Bafna
10:30am|Simonyi 101 and Remote Access

The theory of probabilistically checkable proofs (PCPs) shows how to encode a proof for any theorem into a format where the theorem's correctness can be verified by making only a constant number of queries to the proof. The PCP Theorem [ALMSS] is a...

Nov
01
2024

Special Groups and Dynamics Seminar

Counting Representations of Fuchsian Groups Over Finite Fields
Michael Larsen
2:00pm|Simonyi 101

Recent progress on character bounds for groups of Lie type makes it feasible in many cases to find the asymptotic growth, for fixed q and n tending to infinity, of the number of n-dimensional representations of a Fuchsian group G over the field with...