## Seminars and Colloquia by Series

### Characteristic Classes

Series
Geometry Topology Student Seminar
Time
Wednesday, January 25, 2012 - 14:00 for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Bulent TosunGeorgia Tech
The aim of the talk is to give a complete proof of the fact that any closed oriented 3-manifold has a trivial tangent bundle.

### TBA by Alan Diaz

Series
Geometry Topology Student Seminar
Time
Wednesday, November 9, 2011 - 14:05 for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Alan DiazGeorgia Tech
TBA

### Rays and Souls in Von Mangoldt Planes

Series
Geometry Topology Student Seminar
Time
Wednesday, November 2, 2011 - 14:05 for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Eric ChoiEmory University
Knowledge of rays and critical points of infinity in von Mangoldt planes can be applied to understanding the structure of open complete manifolds with lower radial curvature bounds. We will show how the set of souls is computed for every von Mangoldt plane of nonnegative curvature. We will also make some observations on the structure of the set of critical points of infinity for von Mangoldt planes with negative curvature.

### Introduction to Branched Covers

Series
Geometry Topology Student Seminar
Time
Wednesday, October 26, 2011 - 14:00 for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Meredith CaseyGeorgia Tech
The main purpose of this talk is to better understand how to use branched covers to construct 3-manifolds. We will start with branched covers of 2-manifolds, carefully working through examples and learning the technology. Using these methods in combination with open book decompositions we will show how to construct 3-manifolds by branching over link and knots in S^{3}. Particular emphasis will be placed on using the map to get a "coloring" of the branched locus and how this combinatorial data is useful both for explicit constructions and for the general theory.

### Stein fillings on Lens spaces II

Series
Geometry Topology Student Seminar
Time
Wednesday, October 19, 2011 - 14:05 for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Amey KalotiGeorgia Tech
In this talk we will outline proof due to Plameneveskaya and Van-Horn Morris that every virtually overtwisted contact structure on L(p,1) has a unique Stein filling. We will give a much simplified proof of this result. In addition, we will talk about classifying Stein fillings of ($L(p,q), \xi_{std})$ using only mapping class group basics.

### Stein fillings on Lens spaces.

Series
Geometry Topology Student Seminar
Time
Wednesday, October 5, 2011 - 14:05 for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Amey KalotiGeorgia Tech
In this talk we will outline proof due to Plameneveskaya and Van-Horn Morris that every virtually overtwisted contact structure on L(p,1) has a unique Stein filling. We will give a much simplified proof of this result. In addition, we will talk about classifying Stein fillings of ($L(p,q), \xi_{std})$ using only mapping class group basics.

### Algebraic and geometric aspects of Braid Groups

Series
Geometry Topology Student Seminar
Time
Wednesday, September 28, 2011 - 14:05 for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Marta AguileraGeorgia Tech
In this talk I define the braid groups, its Garside structure, and its application to solve the word and conjugacy problems. I present a braid group with $n$ strands as the mapping class group of the disk with $n$ punctures, $\mathbb{D}^2-\{p_1\ldots p_n\}$, and a classification of surface homeomorphisms by the Nielsen Thurston theorem. I will also discuss results that require algebraic and geometric tools.

### Knot Floer Homology and knot Floer Chain complex CFK^{\infty} II

Series
Geometry Topology Student Seminar
Time
Wednesday, September 7, 2011 - 14:05 for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Bulent TosunGeorgia Tech
Continuation of last week's talk

### Knot Floer Homology and knot Floer Chain complex CFK^{\infty}

Series
Geometry Topology Student Seminar
Time
Wednesday, August 31, 2011 - 14:05 for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Bulent TosunGeorgia Tech

### Character varieties and some applications

Series
Geometry Topology Student Seminar
Time
Wednesday, July 6, 2011 - 14:00 for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Anh TranGeorgia Tech
I will define character varieties of finitely generated groups and consider some applications of them in geometry/topology.