Previous Special Year Seminar

Jan
19
2016

Geometric Structures on 3-manifolds

Low-dimensional dynamics and hyperbolic 3-manifolds
André de Carvalho
2:00pm|S-101

Thurston's hyperbolization of fibered 3-manifolds is based on his classification theorem for isotopy classes of surface homeomorphisms. This classification has also been extremely important to the study of dynamical systems on surfaces. The...

Dec
14
2015

Geometric Structures on 3-manifolds

Quasi-Fuchsian surfaces in finite-volume hyperbolic 3-manifolds
4:00pm|S-101

I will discuss a proof that a complete, non-compact hyperbolic 3- manifold $M$ with finite volume contains an immersed, closed, quasi-Fuchsian surface that separates a given pair of points in the sphere at infinity. Joint with David Futer.

Dec
01
2015

Geometric Structures on 3-manifolds

Volume and homology for hyperbolic 3-orbifolds, and the enumeration of arithmetic groups II
Peter Shalen
4:00pm|S-101

A theorem of Borel's asserts that for any positive real number $V$, there are at most finitely many arithmetic lattices in ${\rm PSL}_2({\mathbb C})$ of covolume at most $V$, or equivalently at most finitely many arithmetic hyperbolid $3$-orbifolds...

Dec
01
2015

Geometric Structures on 3-manifolds

Volume and homology for hyperbolic 3-orbifolds, and the enumeration of arithmetic groups I
Peter Shalen
2:00pm|S-101

A theorem of Borel's asserts that for any positive real number $V$, there are at most finitely many arithmetic lattices in ${\rm PSL}_2({\mathbb C})$ of covolume at most $V$, or equivalently at most finitely many arithmetic hyperbolid $3$-orbifolds...

Nov
24
2015

Geometric Structures on 3-manifolds

Hausdorff dimension of Kleinian group uniformization of Riemann surface and conformal rigidity
2:00pm|S-101

For this talk I'll discuss uniformization of Riemann surfaces via Kleinian groups. In particular question of conformability by Hasudorff dimension spectrum. I'll discuss and pose some questions which also in particular will imply a conjecture due to...

Nov
17
2015

Geometric Structures on 3-manifolds

The complex geometry of Teichmüller spaces and bounded symmetric domains II
Stergios Antonakoudis
4:00pm|S-101

From a complex analytic perspective, Teichmüller spaces and symmetric spaces can be realised as contractible bounded domains, which have several features in common but also exhibit many differences. In this talk we will study isometric maps between...

Nov
12
2015

Geometric Structures on 3-manifolds

Algebraic degrees and Galois conjugates of pseudo-Anosov stretch factors
4:00pm|S-101

We consider questions that arise naturally from the subject of the first talk. The have two main results: 1. In genus $g$, the algebraic degrees of pseudo-Anosov stretch factors include all even numbers between $2$ and $6g - 6$; 2. The Galois...

Nov
12
2015

Geometric Structures on 3-manifolds

Pseudo-Anosov constructions and Penner's conjecture
2:00pm|S-101

In this first talk, we give an introduction to Penner’s construction of pseudo-Anosov mapping classes. Penner conjectured that all pseudo-Anosov maps arise from this construction up to finite power. We give an elementary proof (joint with Hyunshik...

Nov
03
2015

Geometric Structures on 3-manifolds

Random walks on weakly hyperbolic groups
Joseph Maher
4:00pm|S-101

Let $G$ be a group acting by isometries on a Gromov hyperbolic space, which need not be proper. If $G$ contains two hyperbolic elements with disjoint fixed points, then we show that a random walk on $G$ converges to the boundary almost surely. This...