Previous Conferences & Workshops

Dec
12
2017

Computer Science/Discrete Mathematics Seminar II

A PSPACE construction of a hitting set for the closure of small algebraic circuits
Amir Shpilka
10:30am|S-101

We study the complexity of constructing a hitting set for the class of polynomials that can be infinitesimally approximated by polynomials that are computed by polynomial sized algebraic circuits, over the real or complex numbers. Specifically, we...

Dec
12
2017

Locally Symmetric Spaces Seminar

Derived deformation rings for group representations
Søren Galatius
10:00am|Physics Library, Bloomberg Hall 201

It is well known that an irreducible representation of a group $G$ over a field $k$ admits a universal deformation to a representation over a complete Noetherian local ring, provided that it is absolutely irreducible, i.e. remains irreducible after...

Dec
11
2017

Joint IAS/Princeton University Symplectic Geometry Seminar

Recent developments in knot contact homology
Lenny Ng
4:00pm|S-101

Knot contact homology is a knot invariant derived from counting holomorphic curves with boundary on the Legendrian conormal to a knot. I will discuss some new developments around the subject, including an enhancement that completely determines the...

Dec
11
2017

Members’ Seminar

Rigidity and recurrence in symplectic dynamics
2:00pm|S-101

Symplectic Geometry and its dynamics originated from classical mechanics as the geometry of physical phase space, in particular from celestial mechanics, and one of the most driving questions is up to today that of stability for such systems. One of...

Dec
11
2017

Theoretical Machine Learning Seminar

Learning with little data
12:30pm|White-Levy Room

The current successes of deep neural networks have largely come on classification problems, based on datasets containing hundreds of examples from each category. Humans can easily learn new words or classes of visual objects from very few examples...

Dec
11
2017

Computer Science/Discrete Mathematics Seminar I

Recent advances in high dimensional robust statistics
Daniel Kane
11:00am|S-101

It is classically understood how to learn the parameters of a Gaussian even in high dimensions from independent samples. However, estimators like the sample mean are very fragile to noise. In particular, a single corrupted sample can arbitrarily...

Dec
08
2017

Mathematical Conversations

Proofs from algorithms, algorithms from proofs
6:00pm|Dilworth Room

Constructive vs Pure Existence proofs have been a topic of intense debate in foundations of mathematics. Constructive proofs are nice as they demonstrate the existence of a mathematical object by describing an algorithm for building it. In computer...

Dec
08
2017

Special Seminar

Integral points and curves on moduli of local systems
Junho Peter Whang
5:05pm|S-101

The classical affine cubic surface of Markoff has a well-known interpretation as a moduli space for local systems on the once-punctured torus. We show that the analogous moduli spaces for general topological surfaces form a rich family of log Calabi...

Dec
08
2017

Special Seminar

An asymptotic for the growth of Markoff-Hurwitz tuples
Ryan Ronan
4:15pm|S-101

For integer parameters $n \geq 3$, $a \geq 1$, and $k \geq 0$ the Markoff-Hurwitz equation is the diophantine equation \[ x_1^2 + x_2^2 + \cdots + x_n^2 = ax_1x_2 \cdots x_n + k.\] In this talk, we establish an asymptotic count for the number of...

Dec
08
2017

Special Seminar

Integral points on Markoff-type cubic surfaces
3:00pm|S-101

We report on some recent work with Peter Sarnak. For integers $k$, we consider the affine cubic surfaces $V_k$ given by $M(x) = x_1^2 + x_2 + x_3^2 − x_1 x_2 x_3 = k$. Then for almost all $k$, the Hasse Principle holds, namely that $V_k(Z)$ is non...