School of Physical Sciences
Jawaharlal Nehru University, New Delhi
Title : The von Neumann-Day problem for finitely presented groups
Speaker: Yash Lodha (EPFL, Lausanne)
Date: 28– January -2020
Time: 4:00 p.m, Tuesday
Venue: Seminar Room, SPS
Abstract : The so called von Neumann-Day problem asks if there exist nonamenable groups that do not contain nonabelian free subgroups. I will describe a recent solution to the problem for the class of torsion free finitely presented groups (joint with Justin Moore). The groups emerge as groups of homeomorphisms of the real line, and an encoding by means of continued fractions is used to prescribe certain combinatorial structure. This structure allows us to establish that the groups are finitely presented.