Speaker: Yusuke Isono (RIMS, Kyoto Univ.)

Title: Bi-exact groups, strongly ergodic actions and group measure space type III factors with no central sequence

Time/Date: 4:45-6:15, Monday, June 20, 2016,

Room: 118

Abstract: We investigate the asymptotic structure of (possibly type III) crossed product von Neumann algebras arising from arbitrary actions of bi-exact discrete groups (e.g. free groups) on amenable von Neumann algebras. We particularly prove a spectral gap rigidity result for the crossed products and, using recent results of Boutonnet-Ioana-Salehi Golsefidy, we provide examples of group measure space type III factors with no central sequences. This is joint work with C. Houdayer.