- Series
- Geometry Topology Student Seminar
- Time
- Wednesday, September 5, 2012 - 2:00pm for 1 hour (actually 50 minutes)
- Location
- Skiles 006
- Speaker
- Hyunshik Shin – School of Mathematics
- Organizer
- Hyunshik Shin
The main goal is to characterize the dilatation of an outer automorphisms
of free groups. It is known that for any automorphism, its dilatation is a
weak Perron number. The converse was recently shown by Thurston; for every
weak Perron number, there is an automorphism represented by a train track
map. We will discuss Thurston's theorem and its proof.