{ "id": "1912.03686", "version": "v1", "published": "2019-12-08T14:32:07.000Z", "updated": "2019-12-08T14:32:07.000Z", "title": "Intermediate C*-algebras of Cartan Embeddings", "authors": [ "Jonathan H. Brown", "Ruy Exel", "Adam H. Fuller", "David R. Pitts", "Sarah A. Reznikodff" ], "comment": "14 pages", "categories": [ "math.OA" ], "abstract": "Let $A$ be a C$^*$-algebra and let $D$ be a Cartan subalgebra of $A$. We study the following question: if $B$ is a C$^*$-algebra such that $D \\subseteq B \\subseteq A$, is $D$ a Cartan subalgebra of $B$? We give a positive answer in two cases: the case when there is a faithful conditional expectation from $A$ onto $B$, and the case when $A$ is nuclear and $D$ is a C$^*$-diagonal of $A$. In both cases there is a one-to-one correspondence between the intermediate C$^*$-algebras $B$, and a class of open subgroupoids of the groupoid $G$, where $\\Sigma \\rightarrow G$ is the twist associated with the embedding $D \\subseteq A$.", "revisions": [ { "version": "v1", "updated": "2019-12-08T14:32:07.000Z" } ], "analyses": { "subjects": [ "46L05", "22A22", "46L55" ], "keywords": [ "cartan embeddings", "intermediate", "cartan subalgebra", "one-to-one correspondence", "open subgroupoids" ], "note": { "typesetting": "TeX", "pages": 14, "language": "en", "license": "arXiv", "status": "editable" } } }