Previous Conferences & Workshops

Apr
09
2018

Working Group on Diophantine Analysis

Steenrod operations and Tate's Conjecture on the Brauer group of a surface
4:45pm|Fine Hall 1201, Princeton University

There is a canonical pairing on the Brauer group of a surface over a finite field, which is the analogue of the Cassels-Tate pairing on the Tate-Shafarevich group of a Jacobian variety. An old conjecture of Tate predicts that this pairing is...

Apr
09
2018

Joint IAS/Princeton University Symplectic Geometry Seminar

Fukaya categories of Calabi-Yau hypersurfaces
4:00pm|Simonyi Hall 101

Consider a Calabi-Yau manifold which arises as a member of a Lefschetz pencil of anticanonical hypersurfaces in a Fano variety. The Fukaya categories of such manifolds have particularly nice properties. I will review this (partly still conjectural)...

Apr
09
2018

Emerging Topics Working Group

Symplectic geometry of hyperbolic cylinders and their homoclinic intersections
Jean-Pierre Marco
2:00pm|Simonyi Hall 101

Abstract: We first examine the existence, uniqueness, regularity, twist and symplectic properties of compact invariant cylinders with boundary, located near simple or double resonances in perturbations of action-angle systems on the annulus $A^3$...

Apr
09
2018

Computer Science/Discrete Mathematics Seminar I

Large deviations in random graphs
Eyal Lubetzky
11:00am|West Building Lecture Hall

What is the probability that the number of triangles in the Erd\H{o}s-R\'enyi random graph with edge density $p$, is at least twice its mean? What is the typical structure of the graph conditioned on this rare event? For instance, when $p=o(1)$...

Apr
09
2018

Emerging Topics Working Group

Arnold diffusion for `complete' families of perturbations with two or three independent harmonics
Amadeu Delshams
11:00am|Simonyi Hall 101

Abstract: We prove that for any non-trivial perturbation depending on any two independent harmonics of a pendulum and a rotor there is global instability. The proof is based on the geometrical method and relies on the concrete computation of several...

Apr
07
2018

Workshop on Topology: Identifying Order in Complex Systems

Protein Folding Characterization via Persistent Homology
Marcio Gameiro
4:30pm|Simonyi Hall 101

We use persistent homology to analyze predictions of protein folding by trying to identify global geometric structures that contribute to the error when the protein is misfolded. The goal is to find correlations between global geometric structures...

Apr
07
2018

Workshop on Topology: Identifying Order in Complex Systems

Studying Fluid Flows with Persistent Homology
Rachel Levanger
3:00pm|Simonyi Hall 101

We will showcase persistent homology as a promising new tool for use in the study of complicated fluid flows. Through a collection of examples spanning 2D Kolmogorov and Rayleigh-Bénard convection flows to fully-developed 3D turbulence and...

Apr
07
2018

Workshop on Topology: Identifying Order in Complex Systems

Fitting manifolds to data
Charlie Fefferman
1:30pm|Simonyi Hall 101

The problems come in two flavors.

Extrinsic Flavor: Given a point cloud in R^N sampled from an unknown probability density, how can we decide whether that probability density is concentrated near a low-dimensional manifold M with reasonable...

Apr
07
2018

Workshop on Topology: Identifying Order in Complex Systems

Topological filters: a toolbox for processing dynamic signals
Michael Robinson
10:30am|Simonyi Hall 101

Using the geometry of sheaves as the common language, this talk will bridge three separate areas: dynamical systems, signal processing, and data fusion. Because sheaves model consistency relationships between local data, they are easily assembled...