Koç University, Mathematics Seminar

Date & Time: Thursday, November 12, 16:00-17:00

Place: ENG B05

Speaker: Ingrid Irmer (Middle East Technical University)

Title: A family of curve complexes and Chillingworth's winding numbers

Abstract: Curve complexes have traditionally been used to study the mapping class

group of a surface. For the Torelli group, i.e. the subgroup of the mapping class

group that acts trivially on homology, standard techniques do not apply, and

very different style arguments are needed. In this talk, it will be explained how

curve complexes give combinatorial descriptions of the Torelli group invariants

known as Chillingworth's winding numbers.

Speaker’s Brief Biography: I am a Postdoc at METU, on a Tubitak fellowship, visiting Prof. Korkmaz. I work in low dimensional topology and geometric group theory. I did a PhD in Bonn in pure mathematics, and an Honours degree in Theoretical Physics at the Australian National University. When people ask where I am "from" I say I am an earthling with Australian and German citicenship.