Seminar: Functional Analysis and Operator Algebras
Σεμινάριο: Συναρτησιακή Ανάλυση και Άλγεβρες Τελεστών
(Online via zoom)
Friday, April 1, 2022 at 17:00 Athens time
Speaker: Adrian Ioana (UCSD, USA)
Title: Wreath-like product groups and rigidity of their von Neumann algebras
Abstract: In this talk, I will introduce a new class of groups, called wreath-like products. These groups are close relatives of the classical wreath products and arise naturally in the context of group theoretic Dehn filling. Unlike ordinary wreath products, many wreath-like products have Kazhdan's property (T). I will present several new rigidity results for von Neumann algebras of wreath-like products with property (T). In particular, we obtain the first examples of property (T) groups G which are W*-superrigid, in the sense that the group von Neumann algebra L(G) remembers the isomorphism class of G. We also compute the automorphism and fundamental groups of von Neumann algebras of a wide class of wreath-like products. As an application, we show every finitely presented group can be realised as the outer automorprhism group of L(G) for a property (T) group G.
This is based on joint work with Ionut Chifan, Denis Osin and Bin Sun.
Zoom meeting coordinates
upatras-gr.zoom.us/j/99245950296
or
Meeting ID: 992 4595 0296 Passcode: cstaralg
For additional information see the seminar webpage
