Previous Conferences & Workshops

Mar
31
2015

Topology of Algebraic Varieties

Proof of the Grothendieck-Serre conjecture on principal bundles over regular local rings containing a field
2:00pm|S-101

Let $R$ be a regular semi-local domain, containing a field. Let $G$ be a reductive group scheme over $R$. We prove that a principal $G$-bundle over $R$ is trivial, if it is trivial over the fraction field of $R$. If the regular semi-local domain $R$...

Mar
31
2015

Topology of Algebraic Varieties

The projective line minus 3 points II
11:00am|Physics Library, Bloomberg Hall 201

I will try to tell the story of the projective line minus three points from the point of view of periods, and if time permits, discuss some open problems.

Mar
31
2015

Computer Science/Discrete Mathematics Seminar II

Kolmogorov width of discrete linear spaces: an approach to matrix rigidity
10:30am|S-101

A square matrix $V$ is called rigid if every matrix obtained by altering a small number of entries of $V$ has sufficiently high rank. While random matrices are rigid with high probability, no explicit constructions of rigid matrices are known to...

Mar
30
2015

Spectral Geometry Seminar

On the geometry and topology of zero sets of Schrödinger eigenfunctions
3:30pm|S-101

In this talk I will present some new results on the structure of the zero sets of Schrödinger eigenfunctions on compact Riemannian manifolds. I will first explain how wiggly the zero sets can be by studying the number of intersections with a fixed...

Mar
30
2015

Members’ Seminar

Chern classes of Schubert cells and varieties
2:00pm|S-101

Chern-Schwartz-MacPherson class is a functorial Chern class defined for any algebraic variety. I will give a geometric proof of a positivity conjecture of Aluffi and Mihalcea that Chern classes of Schubert cells and varieties in Grassmannians are...

Mar
30
2015

Computer Science/Discrete Mathematics Seminar I

Intelligent learning: similarity control and knowledge transfer
Vladimir Vapnik
11:15am|S-101

During last fifty years a strong machine learning theory has been developed. This theory includes: 1. The necessary and sufficient conditions for consistency of learning processes. 2. The bounds on the rate of convergence which in general cannot be...

Mar
26
2015

Joint IAS/Princeton University Number Theory Seminar

Most odd degree hyperelliptic curves have only one rational point
Bjorn Poonen
4:30pm|S-101

We prove that the probability that a curve of the form $y^2 = f(x)$ over $\mathbb Q$ with $\deg f = 2g + 1$ has no rational point other than the point at infinity tends to 1 as $g$ tends to infinity. This is joint work with Michael Stoll.

Mar
25
2015

Mathematical Conversations

The ABC conjecture, Belyi's theorem and applications
6:00pm|Dilworth Room

We will present the ABC conjecture, Belyi's mapping theorem and explain how they combine into a powerful tool for diophantine problems, following the ideas of Elkies, Bombieri, Granville, Langevin. Finally we will speculate a bit about the function...

Mar
25
2015

Topology of Algebraic Varieties

Framed motives of algebraic varieties (after V. Voevodsky)
11:00am|S-101

This is joint work with G .Garkusha. Using the machinery of framed sheaves developed by Voevodsky, a triangulated category of framed motives is introduced and studied. To any smooth algebraic variety $X$, the framed motive $M_{fr}(X)$ is associated...