2000/01/04 by Dmitri Nikshych, Leonid Vainerman
Mathematics · #math.QA #math.OA
published as Journal of Func. Analysis, 178 no.1, 113-142 (2000) · 32 pages, Latex
arxiv created 2000/01/04 · arxiv updated 2009/11/30
We establish a Galois correspondence for finite quantum groupoid actions on II1 factors and show that every finite index and finite depth subfactor is an intermediate subalgebra of a quantum groupoid crossed product. Moreover, any such a subfactor is completely and canonically determined by a quantum groupoid and its coideal *-subalgebra. This allows to express the bimodule category of a subfactor in terms of the representation category of a corresponding quantum groupoid and the principal graph as the Bratteli diagram of an inclusion of certain C^*-algebras related to it.