Previous Special Year Seminar

Mar
21
2006

Lie Groups, Representations and Discrete Mathematics

Kazhdan's Property (T) for Linear Groups Over General Rings
11:30am|S-101

We will discuss the following very recent result: Theorem. Let R be any finitely generated associative (not necessarily commutative) ring, with 1. Then for any n > stable range rank of the ring R, the group EL_n(R) has Kazhdan's property (T). The...

Mar
07
2006

Lie Groups, Representations and Discrete Mathematics

Asymptotics and Spectra of Cayley and Schreier Graphs of Branch Groups
Zoran Sunik
2:00pm|S-101

We provide calculations of growth and spectra of Cayley and Schreier graphs related to some branch groups. Among the examples, we present a class of groups of intermediate growth defined by primitive polynomials over finite fields (the original...

Mar
03
2006

Arithmetic Homogeneous Spaces

Intersection of Dynamically defined Sets, a Game of Schmidt and a Conjecture of Margulis
Barak Weiss
11:00am|S-101
Feb
28
2006

Lie Groups, Representations and Discrete Mathematics

A Canonical Form for Automorphisms of Totally Disconnected Locally Compact Groups
George Willis
2:00pm|S-101

Let $\alpha$ be an automorphism of a totally disconnected locally compact group $G$. There is a canonical form for $\alpha$ that partially fills the role played by the Jordan canonical form of $\mathrm{ad}( \alpha )$ in the case when $G$ is a Lie...

Feb
21
2006

Lie Groups, Representations and Discrete Mathematics

Lattices of Minimum Covolume in Classical Chevalley Groups over $\mathbb F_q((t))$
Alireza Salehi-Golsefidy
2:00pm|S-101

Studying the covolume of lattices goes back to the work of Siegel in the forties where he shows that $(2,3,7)$-triangular group is a lattice of minimum covolume in $G = \mathrm{SL}_2(\mathbb R)$. The case of $\mathrm{SL}_2(\mathbb C)$ has been open...

Feb
17
2006

Arithmetic Homogeneous Spaces

Primes in Tuples
D. Goldston
11:00am|S-101

I will describe recent joint work with Janos Pintz and Cem Yildirim on small gaps between primes and primes in tuples. Perhaps the most surprising result is that if the primes have level of distributed in arithmetic progressions greater than 1/2...