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Related papers: Outer actions of measured quantum groupoids

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The paper contains a description of the KMS weights for the one-parameter action on the reduced C*-algebra of a second countable locally compact Hausdorff etale groupoid, arising from a continuous real valued homomorphism satisfying two…

Operator Algebras · Mathematics 2013-06-24 Klaus Thomsen

In this article, when G is a locally compact quantum group, we associate to a braided-commutative G-Yetter-Drinfel'd algebra $(N,a,\hat{a})$ equipped with a normal faithful semi-finite weight verifying some appropriate condition, a…

Operator Algebras · Mathematics 2017-03-21 Michel Enock , Thomas Timmermann

We give some sufficient conditions for the injectivity of actions of compact quantum groups on $C^{\ast}$-algebra. As an application, we prove that any faithful smooth action by a compact quantum group on a compact smooth (not necessarily…

Operator Algebras · Mathematics 2018-06-08 D Goswami , S Joardar

In this work we give a generalization of matched pairs of (finite) groups to describe a general class of depth two inclusions of factor von Neumann algebras and the C*-quantum groupoids associated with, using double groupoids.

Operator Algebras · Mathematics 2007-05-23 Jean-Michel Vallin

Using an approach emerging from the theory of closable derivations on von Neumann algebras, we exhibit a class of groups CR satisfying the following property: given any groups G_1, G_2 in CR, then any free, ergodic, measure preserving…

Operator Algebras · Mathematics 2019-12-19 Ionut Chifan , Jesse Peterson

Bichon, De Rijdt and Vaes introduced the notion of monoidally equivalent compact quantum groups. In this paper we prove that there is a natural bijective correspondence between actions of monoidally equivalent quantum groups on unital…

Operator Algebras · Mathematics 2011-11-09 An De Rijdt , Nikolas Vander Vennet

Actions of locally compact groups and quantum groups on W*-ternary rings of operators are discussed and related crossed products introduced. The results generalise those for von Neumann algebraic actions with proofs based mostly on passing…

Operator Algebras · Mathematics 2017-10-18 Pekka Salmi , Adam Skalski

Starting from any proper action of any locally compact quantum group on any discrete quantum space, we show that its equivariant representation theory yields a concrete unitary 2-category of finite type Hilbert bimodules over the discrete…

Operator Algebras · Mathematics 2025-08-27 Lukas Rollier

We define bounded cohomology of $t$-discrete measured groupoids with coefficients into measurable bundles of Banach spaces. Our approach via homological algebra extends the classic theory developed by Ivanov and by Monod. As a consequence,…

Algebraic Topology · Mathematics 2025-03-31 Filippo Sarti , Alessio Savini

If a compact quantum group acts faithfully and smoothly (in the sense of Goswami 2009) on a smooth, compact, oriented, connected Riemannian manifold such that the action induces a natural bimodule morphism on the module of sections of the…

Operator Algebras · Mathematics 2014-11-17 Debashish Goswami

We introduce a general notion of quantum universal enveloping algebroids (QUE algebroids), or quantum groupoids, as a unification of quantum groups and star-products. Some basic properties are studied including the twist construction and…

Quantum Algebra · Mathematics 2016-09-07 Ping Xu

We prove a mean ergodic theorem for amenable discrete quantum groups. As an application, we prove a Wiener type theorem for continuous measures on compact metrizable groups.

Operator Algebras · Mathematics 2016-07-14 Huichi Huang

We classify outer actions (or $\mathscr{G}$-kernels) of discrete amenable groupoids on injective factors. Our method based on unified approach for classification of discrete amenable groups actions, and cohomology reduction theorem of…

Operator Algebras · Mathematics 2020-08-25 Toshihiko Masuda

We generalize the representation theorem of Junge, Neufang and Ruan [A representation theorem for locally compact quantum groups, Internat. J. Math. 20(3) (2009) 377-400], and some of the important results which were used in its proof, to…

Operator Algebras · Mathematics 2013-04-16 Mehrdad Kalantar

In his thesis ([L1]), which is published in an expended and revised version ([L2]), Franck Lesieur had introduced a notion of measured quantum groupoid, in the setting of von Neumann algebras, using intensively the notion of…

Operator Algebras · Mathematics 2007-06-12 Michel Enock

The quantum completion of the space of connections in a manifold can be seen as the set of all morphisms from the groupoid of the edges of the manifold to the (compact) gauge group. This algebraic construction generalizes the analogous…

High Energy Physics - Theory · Physics 2017-08-23 J. M. Velhinho

We show that any compact group can be realized as the outer automorphism group of a factor of type II_1. This has been proved in the abelian case by Ioana, Peterson and Popa applying Popa's deformation/rigidity techniques to amalgamated…

Operator Algebras · Mathematics 2008-04-04 Sébastien Falguières , Stefaan Vaes

We introduce and study the notions of boundary actions and of the Furstenberg boundary of a discrete quantum group. As for classical groups, properties of boundary actions turn out to encode significant properties of the operator algebras…

Operator Algebras · Mathematics 2022-06-22 Mehrdad Kalantar , Paweł Kasprzak , Adam Skalski , Roland Vergnioux

Definition of a smooth action of a CQG on a compact, smooth manifold is given and studied. It is shown that a smooth action is always injective. Furthermore A necessary and sufficient condition for a lift of the smooth action as a bimodule…

Quantum Algebra · Mathematics 2015-07-31 Debashish Goswami , Soumalya Joardar

We prove that every topological action of a countable group on a metrizable space can be realized as a bi-Lipschitz action with respect to some compatible metric. This extends a result due to U. Hamenst\"{a}dt regarding finitely generated…

Group Theory · Mathematics 2024-10-11 Inhyeok Choi , Sang-hyun Kim