Speaker: Valerio Proietti (Univ. Tokyo)

Title: A geometric Elliott invariant and noncommutative rigidity of mapping tori

Time/Date: 4:45-6:15pm, October 18 (Tue), 2022.

Room: 128 Math Sci Building (It will be also online. The Zoom link is the same as before. If you don't have one, please ask Kawahigashi.)

Abstract: Given a class of topological dynamical systems, we study the associated mapping torus from the point of view of foliated spaces. By studying the interaction between the leafwise Dirac operator and the invariant transverse measures, we completely reframe in a geometric fashion the Elliott invariant for the crossed product of the dynamical system, and prove a rigidity result for the mapping torus, lifting leafwise homotopy equivalences to isomorphism of the noncommutative leaf space. If time allows, we will see an application of the main theorem to the study quasi-crystals.