# Talks

This page is an archive of slides for talks that I have given. Unfortunately, I like to use animations in my talks, so most of the slides are in either PowerPoint format or Mathematica.

## Rearrangement Groups of Fractals

My most recent research talk discusses a general class of groups that act on self-similar graph-like spaces. I gave this talk in the

Binghamton Univerisity Geometry and Topology Seminar in April 2015.

## Talks on 2*V*

Here are the slides for my talk on the torsion problem in

$2$*V* and the undecidability of the finiteness problem for groups of asynchronous automata, which is based on my recent

preprint with Collin Bleak. I gave this talk at several different seminars in the fall of 2013:

(This PDF was created from images of the

original Mathematica slides. It includes a few still frames of the original animations.)

Here are the slides for a slightly different version of this talk that I gave at the Workshop on the Extended Family of R. Thompson Groups at the University of St Andrews in May 2014. They include some extra material on subshifts from my joint work with Francesco Matucci, Brita Nucinkis, and Conchita Martínez-Pérez, but do not include any introductory material on Thompson's groups.

## Thompson-Like Groups Acting on Julia Sets

Here are the slides for my talk on Thompson-like groups acting on Julia sets, which cover some joint work with Bradley Forrrest. I gave this talk at the

University of St Andrews Analysis Research Group in October 2013, and I also gave shorter versions of this talk at the

Groups St Andrews 2013 conference, as well as the Workshop on the Extended Family of R. Thompson Groups conference at St Andrews in 2014.

(This PDF was created from images of the original Mathematica slides. It includes a few still frames of the original animations.)

Here is a PDF of the shorter, 20-min. version of this talk that I gave at the Groups St Andrews conference. The PDF includes a few of my Mathematica animations:

## A Thompson Group for the Basilica

Here are the slides for the older talk I gave on the Basilica Thompson group. I gave this talk at the University of Virginia Algebra seminar and the Binghamton University Geometry and Topology Seminar in April 2012.

## Fractals and Dynamics

I have given several different talks on fractals, fractal geometry, and dynamical systems. The most recent was at

Stockton College Mathematics Seminar in November 2010:

I also gave a talk on fractals in August 2008 and again in August 2009 as part of Bard's

Language & Thinking Program for incoming first-years. This talk was aimed at a general audience:

**Links**

Here are some links and resources related to these talks:

## Geometric Group Theory

I have also given several talks on geometric group theory, starting when I was a graduate student. The most recent was given in the Bard math seminar, and did not actually involve any groups:

I also gave two talks at the postdoc colloquium while I was at

Texas A&M University. These talks were aimed at an audience of math professors. The first discussed a bit of general geometric group theory, and then introduces Thompson's group:

Here is another relatively expository talk on Thompson's groups that I gave at the 2008 Joint Mathematics Meetings in San Diego:

I also have a full-length seminar talk on my joint work with Francesco Matucci. I gave a version of this talk in the Texas A&M Groups and Dynamics seminar, in the University of Virginia Topology Seminar, and in the Cornell Topology and Geometric Group Theory seminar:

Finally, here is a talk on length and isoperimetric inequalities in Thompson's group

*F* that I gave in the Texas A&M Groups and Dynamics seminar. This is essentially a longer version of the talk I gave in my thesis defense:

## Cryptology

Here are the slides for a talk I gave at the 2008 Joint Mathematics Meetings in San Diego on a cryptology course that I taught at Cornell:

You can also download the Excel-based midterm exam that I gave in a computer lab:

(The exam is locked, but the password is “password”.)