Previous Conferences & Workshops

Jan
28
2010

Analytic and Geometric Number Theory Seminar

Bounds Toward Ramanujan Over a Number Field
Farrell Brumley
2:00pm|S-101

A result of Kim-Sarnak (2003) gives the best known bounds towards the Ramanujan conjecture for Maass forms. The technique employed has not, until now, been made to apply to general GL2 cusp forms over number fields whose unit group is infinite. In...

Jan
26
2010

Geometry/Dynamical Systems Seminar

Rabinowitz-Floer Homology
Urs Frauenfelder
4:00pm|S-101

Rabinowitzi-Floer homology is the semi-infinite dimensional Morse homology associated to an action functional which played a major role in the pioneering work of Rabinowitz. Critical points of Rabinowitz action functional are Reeb orbits while...

Jan
26
2010

Computer Science/Discrete Mathematics Seminar II

Representation Theory and Expansion in Groups
10:30am|S-101

In this survey lecture (which will continue on Tue Feb 2) I plan to explain basic aspects of the representation theory of finite groups, and how these are applied to various questions regarding expansion and random walks on groups. These...

Jan
25
2010

Geometry and Materials Seminar

Liquid Crystals, Minimal Surfaces, and Elliptic Functions
Randall Kamien
3:30pm|S-101

Liquid crystals form layered structures, known as smectics. Modeling these structures as minimal surfaces gives a class of trial solutions from which we can estimate ground state energetics. In order to control the boundary conditions, or topology...

Jan
25
2010

Members’ Seminar

Pretentiousness in the Analytic Theory of Numbers
2:00pm|S-101

Following the brilliant insight of Riemann, that a good understanding of the distribution of prime numbers is equivalent to a good understanding of the location of zeros of pertinent L-functions, analytic number theory has traditionally centered on...

Jan
25
2010

Computer Science/Discrete Mathematics Seminar I

Expanders and Communication-Avoiding Algorithms
Oded Schwartz
11:15am|S-101

Algorithms spend time on performing arithmetic computations, but often more on moving data, between the levels of a memory hierarchy and between parallel computing entities. Judging by the hardware evolution of the last few decades, the fraction of...

Jan
21
2010

Special Geometry/Dynamical Systems Seminar

Contraction of Areas and Topology of Mappings
4:30pm|S-101

The k-dilation of a mapping F measures how much the mapping stretches k-dimensional areas. If a map F has k-dilation L , then it maps each k-dimensional surface of k-volume V to an image of k-volume at most LV. If the k-dilation of a map is very...

Jan
21
2010

Analytic and Geometric Number Theory Seminar

The Positive Density Conjecture for Integral Apollonian Packings
Elena Fuchs
2:00pm|S-101

A bounded Apollonian circle packing (ACP) is an ancient Greek construction which is made by repeatedly inscribing circles into the triangular interstices in a Descartes configuration of four mutually tangent circles. Remarkably, if the original four...

Jan
20
2010

Special Geometry/Dynamical Systems Seminar

Using Dvir's Polynomial Method in Euclidean Space
2:00pm|S-101

In 2007, Dvir proved the Kakeya conjecture over finite fields. His proof uses the polynomial method: we take a hypothetical strange set, find a polynomial that vanishes on the set, and use properties of polynomials to show that the set does not...

Jan
19
2010

Computer Science/Discrete Mathematics Seminar II

Limits of Randomly Grown Graph Sequences
10:30am|S-101

Motivated in part by various sequences of graphs growing under random rules (like internet models), convergent sequences of dense graphs and their limits were introduced by Borgs, Chayes, Lovasz, Sos and Vesztergombi and by Lovasz and Szegedy. In...