Previous Conferences & Workshops

Jan
21
2011

Geometry/Dynamical Systems Seminar

The Cartan Geometry of the Rotating Kepler Problem
Otto van Koert
4:00pm|S-101

In this talk we shall discuss the Cartan geometry of the rotating Kepler problem. The rotating Kepler problem appears as the limit of the restricted planar three-body body when one of the masses goes to zero. As such, this problem plays the role of...

Jan
20
2011

Special Seminar

Mechanizing the Odd Order Theorem: Local Analysis
Georges Gonthier
4:00pm|S-101

Abstract: In addition to formal definitions and theorems, mathematical theories also contain clever, context-sensitive notations, usage conventions, and proof methods. To mechanize advanced mathematical results it is essential to capture these more...

Jan
20
2011

Galois Representations and Automorphic Forms Seminar

Local-Global Compatibility and Monodromy
2:15pm|S-101

Given a cuspidal automorphic representation of GL(n) which is regular algebraic and conjugate self-dual, one can associate to it a Galois representation. This Galois representation is known in most cases to be compatible with local Langlands. When n...

Jan
20
2011

Analysis/Mathematical Physics Seminar

Fluctuations of the Nodal Line Length of Laplace eigenfunctions on the Arithmetic torus
Igor Wigman
1:00pm|S-101

Using the spectral multiplicities of the standard torus, we endow the Laplace eigenspace with Gaussian probability measure. This induces a notion of a random Gaussian Laplace eigenfunctions on the torus. We study the distribution of nodal length of...

Jan
19
2011

Geometry/Dynamical Systems Seminar

Weak Stability Boundary and Capture in the Three-Body Problem
Edward Belbruno
4:00pm|S-101

The problem of capture in the planar restricted three-body problem is addressed. In particular, weak capture is described, which occurs at a complicated region called the weak stability boundary, where the motion is chaotic in nature. It was first...

Jan
19
2011

Geometry/Dynamical Systems Seminar

Contacting the Moon
Urs Frauenfelder
2:00pm|S-101

The restricted 3-body problem has an intriguing dynamics. A deep observation of Jacobi is that in rotating coordinates the problem admits an integral. In joint work with P. Albers, G. Paternain and O. van Koert, we proved that the corresponding...

Jan
18
2011

Computer Science/Discrete Mathematics Seminar II

Efficiently Learning Mixtures of Gaussians
10:30am|S-101

Given data drawn from a mixture of multivariate Gaussians, a basic problem is to accurately estimate the mixture parameters. We provide a polynomial-time algorithm for this problem for any fixed number ($k$) of Gaussians in $n$ dimensions (even if...

Jan
17
2011

Computer Science/Discrete Mathematics Seminar I

Cross-Validation and Mean-Square Stability
Sergei Vassilvitskii
11:15am|S-101

A popular practical method of obtaining a good estimate of the error rate of a learning algorithm is k-fold cross-validation. Here, the set of examples is first partitioned into k equal-sized folds. Each fold acts as a test set for evaluating the...