Invertibility in groupoid C*-algebras

Abstract

Given a second-countable, Hausdorff, \'etale, amenable groupoid G with compact unit space, we show that an element a in C*(G) is invertible if and only if λx(a) is invertible for every x in the unit space of G, where λx refers to the "regular representation" of C*(G) on l2(Gx). We also prove that, for every a in C*(G), there exists some x in G(0) such that ||a|| = ||λx(a)||.

0

Turn this paper into a lesson

ArcXiv compiles a structured reading guide from this paper's metadata: plain-English importance, contributions, prerequisite concepts, which sections to read first, flashcards, and a quiz. Grounded in the abstract, never invented.

Discussion (0)

Sign in to join the discussion.

Loading comments…