We are back with Season 2 of Virtual Geometric Structures, an online seminar series on the broad area of Topology and Geometry. The lectures in VGS are aimed at PhD students and early career researchers. There will be an informal discussion session after every talk. We strongly encourage the participants to take part in this discussion.

If you wish to receive email announcements from us, please register here.

Zoom meeting details for VGS lectures will be as follows:

Meeting ID: 859 1456 3909 Passcode: VGS2 (this may change later)

If you want to suggest speakers, please send an email to arpaninto@outlook.com

Lecture 1 (by Dr. Stephan Tillmann, April 08, 2022, 11:00 AM IST) ( recording )

Title: What is the Thurston norm?

Abstract: Thurston's norm on (co)homology of a 3-manifold reveals interesting topological properties of the 3-manifold. At the centre of its study is its unit ball, which is a finite polytope. Associated to some of its top dimensional faces are special triangulations of the manifold defined by Agol, called veering triangulations. After a general introduction to these topics, I will outline algorithms developed in collaboration with Daryl Cooper and Will Worden to compute the unit ball of the Thurston norm.

Lecture 2 (by Dr. Sean Lawton, May 17, 2022, 08:00 PM IST) ( recording )

Title: Dynamics on Nilpotent Character Varieties

Abstract: Let N be a finitely generated nilpotent group and G a compact connected Lie group. In collaboration with J-P Burelle, we show that there is a natural Out(N)-invariant radon measure with full support on the identity component of the conjugation quotient Hom(N,G)/G and that Out(N) is strong mixing with respect to this measure whenever there exists an element in Out(N) whose eigenvalues are not roots of unity. In this talk, I will discuss an example of this theorem in detail.