A uniqueness theorem for twisted groupoid C*-algebras

Abstract: Twisted groupoid C*-algebras were introduced by Renault in 1980 and are a generalisation of twisted group C*-algebras, which are the C*-algebraic analogue of twisted group rings. Through the work of Renault and more recently of Li, it has emerged that every simple classifiable C*-algebra can be realised as a twisted groupoid C*-algebra, a result that has led to increased interest in the structure of these C*-algebras. In this talk I will describe the construction of reduced twisted C*-algebras of Hausdorff étale groupoids. I will then discuss my recent preprint in which I prove a uniqueness theorem for these algebras and use this to characterise simplicity in the case where the groupoid is effective.

geometric topologynumber theoryoperator algebrasrepresentation theory

Audience: researchers in the topic

( paper | video )

Noncommutative Geometry in NYC

Series comments: Noncommutative Geometry studies an interplay between spatial forms and algebras with non-commutative multiplication. Our seminar welcomes talks in Number Theory, Geometric Topology and Representation Theory linked to the context of Operator Algebras. All talks are kept at the entry-level accessible to the graduate students and non-experts in the field. To join us click sju.webex.com/meet/nikolaei (5 min in advance) and igor DOT v DOT nikolaev AT gmail DOT com to subscribe/unsubscribe for the mailing list, to propose a talk or to suggest a speaker. Pending speaker's consent, we record and publish all talks at the hyperlink "video" on speaker's profile at the "Past talks" section. The slides can be posted by providing the organizers with a link in the format "myschool.edu/~myfolder/myslides.pdf". The duration of talks is 1 hour plus or minus 10 minutes.