Seminars & Colloquia Calendar
Exploring algebraic rigidity in mapping class groups
Nicholas Vlamis (CUNY)
Location: Hill 005
Date & time: Tuesday, 09 April 2019 at 3:30PM - 4:30PM
Abstract: A classical theorem of Powell (with roots in the work of Mumford and Birman) states that the pure mapping class group of a connected, orientable, finite-type surface of genus at least 3 is perfect, that is, it has trivial abelianization. We will discuss how this fails for infinite-genus surfaces and give a complete characterization of all homomorphisms from pure mapping class groups of infinite-genus surfaces to the integers. This characterization yields a direct connection between algebraic invariants of pure mapping class groups and topological invariants of the underlying surface.
This is joint work with Javier Aramayona and Priyam Patel.