Previous Conferences & Workshops

Nov
24
2025

Joint IAS/PU Arithmetic Geometry

Characteristic Classes of $p$-adic Local Systems
Alexander Petrov
3:30pm|Princeton University, Fine 224

A cohomology class of the group GL_n(Q_p) gives rise to a characteristic class of Q_p-local systems on algebraic varieties or topological spaces. It turns out that all rational primitive cohomology classes (in degrees >1) give vanishing...

Nov
24
2025

Joint IAS/PU Analysis and Mathematical Physics

Inviscid Limits From Compressible Navier-Stokes to Small BV Solutions to Euler
Alexis Vasseur
3:00pm|Simonyi Hall 101 and Remote Access

The compressible Euler equation can lead to the emergence of shock discontinuities in finite time, notably observed behind supersonic planes. A very natural way to justify these singularities involves studying solutions as inviscid limits of Navier...

Nov
24
2025

Members' Colloquium

Visualizing Ricci Flow
1:30pm|Simonyi 101 and Remote Access

Riemannian metrics are the simplest generalizations of Euclidean geometry to smooth manifolds. The Ricci curvature of a metric measures, in an averaged sense, how the geometry deviates from being flat. The tensor $-2\,\mathrm{Ric}$ can be viewed as...

Nov
24
2025

Computer Science/Discrete Mathematics Seminar I

Why Language Models Hallucinate
Adam Kalai
11:00am|Simonyi Hall 101 and Remote Access

Large language models (LLMs) sometimes generate statements that are plausible but factually incorrect—a phenomenon commonly called "hallucination." We argue that these errors are not mysterious failures of architecture or reasoning, but rather...

Nov
21
2025

IAS/Princeton/Montreal/Paris/Tel-Aviv Symplectic Geometry Zoominar

Higher Dimensional Birkhoff Attractors
Vincent Humilière
9:15am|Remote Access

The Birkhoff attractor is a closed invariant subset associated with any dissipative twist map of the annulus (of dimension 2), which was introduced by Birkhoff in 1932. We will see that it can be generalized to higher dimensions using tools from...

Nov
20
2025

Joint IAS/PU Number Theory

From Automorphic Periods to Arithmetic: The Case of Hilbert Modular Forms
3:30pm|Simonyi 101 and Remote Access

The theory of Euler systems, first developed by Thaine and Kolyvagin, has become a central tool for proving cases of the Birch–Swinnerton-Dyer and Bloch–Kato conjectures. Many of the known examples are inspired from automorphic period integrals that...

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
19
2025

What is...?

What is... a Non Local Game?
12:45pm|Simonyi 101 and Remote Access

In the 1930s, Einstein, Podolsky and Rosen devised the "EPR paradox", which shed light on a peculiar phenomenon in the mathematical modeling of quantum mechanics:  Very far apart particles can exhibit correlated behaviour, which seemed to suggest a...

Nov
18
2025

Joint IAS/PU Groups and Dynamics Seminar

Representations of Binary by Quaternary Quadratic Form
4:30pm|Simonyi 101

Let $q,Q$ be two integral quadratic forms in $m n$
variables. One can ask when $q$ can be represented by $Q$ - that is,
whether there exists an $n \times m$-integer matrix $T$ such that $ Q \circ T = q $.  Naturally, a necessary condition is that...