29 citations · 116 across the 26 of their papers we have counts for
34 papers
Delocalised traces on Hecke algebras of right-angled, hyperbolic type
Piotr Nowak, Sanaz Pooya, Sven Raum +1
For every Hecke C*-algebra of right-angled, hyperbolic type, we construct a smooth subalgebra to which traces associated with arbitrary conjugacy classes in the associated Coxeter…
Strict comparison for twisted group C*-algebras
Sven Raum, Hannes Thiel, Eduard Vilalta
We prove that any reduced twisted group C*-algebra of a selfless group with the rapid decay property is selfless. As an application, we show that twisted group C*-algebras of acyli…
Twisted group C*-algebras of acylindrically hyperbolic groups have stable rank one
Sven Raum
We prove that the twisted group C*-algebra of an acylindrically hyperbolic group -- not necessarily having trivial finite radical -- has stable rank one.
Free actions of polynomial growth Lie groups and classifiable C*-algebras
Ulrik Enstad, Gabriel Favre, Sven Raum
We show that any free action of a connected Lie group of polynomial growth on a finite dimensional locally compact space has finite tube dimension. This is shown to imply that the…
Detecting ideals in reduced crossed product C*-algebras of topological dynamical systems
Are Austad, Sven Raum
We introduce the -ideal intersection property for crossed product C*-algebras. It is implied by C*-simplicity as well as C*-uniqueness. We show that topological dynamical s…
On the centre of Iwahori-Hecke algebras
Timothée Marquis, Sven Raum
We prove triviality of the centre of arbitrary Hecke algebras of irreducible non-finite non-affine type. This result is obtained as a consequence of the following structure result…
A dynamical approach to sampling and interpolation in unimodular groups
Ulrik Enstad, Sven Raum
We introduce a notion of covolume for point sets in locally compact groups that simultaneously generalizes the covolume of a lattice and the reciprocal of the Beurling density for…
The ideal intersection property for essential groupoid C*-algebras
Matthew Kennedy, Se-Jin Kim, Xin Li +2
We characterise, in several complementary ways, étale groupoids with locally compact Hausdorff space of units whose essential groupoid C*-algebra has the ideal intersection propert…
Classifying right-angled Hecke C*-algebras via K-theoretic invariants
Sven Raum, Adam Skalski
Exploiting the graph product structure and results concerning amalgamated free products of C*-algebras we provide an explicit computation of the K-theoretic invariants of right-ang…
Amenability, proximality and higher order syndeticity
Matthew Kennedy, Sven Raum, Guy Salomon
We show that the universal minimimal proximal flow and the universal minimal strongly proximal flow of a discrete group can be realized as the Stone spaces of translation invariant…
An algebraic characterization of ample type I groupoids
Gabriel Favre, Sven Raum
We give algebraic characterizations of the type I and CCR properties for locally compact second countable, ample Hausdorff groupoids in terms of subquotients of their Boolean inver…
Factorial multiparameter Hecke von Neumann algebras and representations of groups acting on right-angled buildings
Sven Raum, Adam Skalski
We obtain a complete characterisation of factorial multiparameter Hecke von Neumann algebras associated with right-angled Coxeter groups. Considering their -convolution alg…
Measure equivalence for non-unimodular groups
Juhani Koivisto, David Kyed, Sven Raum
We undertake a comprehensive study of measure equivalence between general locally compact, second countable groups, providing operator algebraic and ergodic theoretic reformulation…
Cartan subalgebras in dimension drop algebras
Selçuk Barlak, Sven Raum
We completely classify Cartan subalgebras of dimension drop algebras with coprime parameters. More generally, we classify Cartan subalgebras of arbitrary stabilised dimension drop…
C*-superrigidity of 2-step nilpotent groups
Caleb Eckhardt, Sven Raum
We show that torsion-free finitely generated nilpotent groups are characterised by their group C*-algebras and we additionally recover their nilpotency class as well as the subquot…
Traces on reduced group C*-algebras
Matthew Kennedy, Sven Raum
In this short note we prove that the reduced group C*-algebra of a locally compact group admits a non-zero trace if and only if the amenable radical of the group is open. This comp…
Measure equivalence and coarse equivalence for unimodular locally compact groups
Juhani Koivisto, David Kyed, Sven Raum
This article is concerned with measure equivalence and uniform measure equivalence of locally compact, second countable groups. We show that two unimodular, locally compact, second…
L^2-Betti numbers of rigid C*-tensor categories and discrete quantum groups
David Kyed, Sven Raum, Stefaan Vaes +1
We compute the -Betti numbers of the free -tensor categories, which are the representation categories of the universal unitary quantum groups . We show that the $…
Higher l^2-Betti numbers of universal quantum groups
Julien Bichon, David Kyed, Sven Raum
We calculate all -Betti numbers of the universal discrete Kac quantum groups as well as their full half-liberated counterparts .
Locally compact groups acting on trees, the type I conjecture and non-amenable von Neumann algebras
Cyril Houdayer, Sven Raum
We address the problem to characterise closed type I subgroups of the automorphism group of a tree. Even in the well-studied case of Burger-Mozes' universal groups, non-type I crit…
On the l^2-Betti numbers of universal quantum groups
David Kyed, Sven Raum
We show that the first -Betti number of the duals of the free unitary quantum groups is one, and that all -Betti numbers vanish for the duals of the quantum automor…
Cocompact amenable closed subgroups: weakly inequivalent representations in the left-regular representation
Sven Raum
We show that if is a closed amenable and cocompact subgroup of a unimodular locally compact group, then the reduced group C*-algebra of is not simple. Equivalently,…
C*-simplicity of locally compact Powers groups
Sven Raum
In this article we initiate research on locally compact C*-simple groups. We first show that every C*-simple group must be totally disconnected. Then we study C*-algebras and von N…
Asymptotic structure of free Araki-Woods factors
Cyril Houdayer, Sven Raum
The purpose of this paper is to investigate the structure of Shlyakhtenko's free Araki-Woods factors using the framework of ultraproduct von Neumann algebras. We first prove that a…