97 citations · 519 across the 71 of their papers we have counts for
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Invariant von Neumann subalgebras of crossed products and tensor products
Tattwamasi Amrutam, Artem Dudko, Yongle Jiang +1
Let be a countable discrete group acting on a tracial von Neumann algebra in a trace-preserving way. We study invariant von Neumann subalgebras of and of…
Quantum isometry groups of log-Laplacians on Cuntz--Krieger algebras
Amaury Freslon, Dimitris Michail Gerontogiannis, Adam Skalski
We compute the quantum isometry groups of Cuntz-Krieger algebras endowed with the spectral triples coming from the Ahlfors regular structure of the underlying topological Markov ch…
Invariant subalgebras rigidity for von Neumann algebras of groups arising as certain semidirect products
Tattwamasi Amrutam, Artem Dudko, Yongle Jiang +1
We study the ISR (von Neumann invariant subalgebra rigidity) property for certain discrete groups arising as semidirect products from algebraic actions on certain 2-torsion groups,…
A quantum Frucht's theorem and quantum automorphisms of quantum Cayley graphs
Michael Brannan, Daniel Gromada, Junichiro Matsuda +2
We establish a quantum version of Frucht's Theorem, proving that every finite quantum group is the quantum automorphism group of an undirected finite quantum graph. The constructio…
Asymptotic invariants for fusion algebras associated with compact quantum groups
Jacek Krajczok, Adam Skalski
We introduce and study certain asymptotic invariants associated with fusion algebras (equipped with a dimension function), which arise naturally in the representation theory of com…
Tracial central states on compact quantum groups
Amaury Freslon, Adam Skalski, Simeng Wang
Motivated by classical investigation of conjugation invariant positive-definite functions on discrete groups, we study tracial central states on universal C*-algebras associated wi…
Convolution semigroups on Rieffel deformations of locally compact quantum groups
Adam Skalski, Ami Viselter
Consider a locally compact quantum group with a closed classical abelian subgroup equipped with a -cocycle . We study in detail…
Separation properties for positive-definite functions on locally compact quantum groups and for associated von Neumann algebras
Jacek Krajczok, Adam Skalski
Using Godement mean on the Fourier-Stieltjes algebra of a locally compact quantum group we obtain strong separation results for quantum positive-definite functions associated to a…
Full solution of the factoriality question for -Araki-Woods von Neumann algebras via conjugate variables
Manish Kumar, Adam Skalski, Mateusz Wasilewski
We establish factoriality of -Araki-Woods von Neumann algebras (with the number of generators at least two) in full generality, exploiting the approach via conjugate variables d…
Coupling capacity in C*-algebras
Adam Skalski, Ivan G. Todorov, Lyudmila Turowska
Given two unital C*-algebras equipped with states and a positive operator in the enveloping von Neumann algebra of their minimal tensor product, we define three parameters that mea…
Relative Haagerup property for arbitrary von Neumann algebras
Martijn Caspers, Mario Klisse, Adam Skalski +2
We introduce the relative Haagerup approximation property for a unital, expected inclusion of arbitrary von Neumann algebras and show that if the smaller algebra is finite then the…
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…
The RFD and KAC quotients of the Hopf*-algebras of universal orthogonal quantum groups
Biswarup Das, Uwe Franz, Adam Skalski
We determine the Kac quotient and the RFD (residually finite dimensional) quotient for the Hopf *-algebras associated to universal orthogonal quantum groups.
On the Baum--Connes conjecture for discrete quantum groups with torsion and the quantum Rosenberg Conjecture
Yuki Arano, Adam Skalski
We give a decomposition of the equivariant Kasparov category for discrete quantum group with torsions. As an outcome, we show that the crossed product by a discrete quantum group i…
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…
The Haagerup property for twisted groupoid dynamical systems
Bartosz Kwaśniewski, Kang Li, Adam Skalski
We introduce the Haagerup property for twisted groupoid -dynamical systems in terms of naturally defined positive-definite operator-valued multipliers. By developing a version…
Noncommutative Furstenberg boundary
Mehrdad Kalantar, Paweł Kasprzak, Adam Skalski +1
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…
Fixed points and limits of convolution powers of contractive quantum measures
Matthias Neufang, Pekka Salmi, Adam Skalski +1
We study fixed points of contractive convolution operators associated to contractive quantum measures on locally compact quantum groups. We characterise the existence of non-zero f…
Maximal subgroups and von Neumann subalgebras with the Haagerup property
Yongle Jiang, Adam Skalski
We initiate a study of maximal subgroups and maximal von Neumann subalgebras which have the Haagerup property. We determine maximal Haagerup subgroups inside $\mathbb{Z}^2 \rtimes…
Generating functionals for locally compact quantum groups
Adam Skalski, Ami Viselter
Every symmetric generating functional of a convolution semigroup of states on a locally compact quantum group is shown to admit a dense unital -subalgebra with core-like propert…
On C*-completions of discrete quantum group rings
Martijn Caspers, Adam Skalski
We discuss just infiniteness of C*-algebras associated to discrete quantum groups and relate it to the C*-uniqueness of the quantum groups in question, i.e. to the uniqueness of a…
Quantum symmetries of the twisted tensor products of C*-algebras
Jyotishman Bhowmick, Arnab Mandal, Sutanu Roy +1
We consider the construction of twisted tensor products in the category of C*-algebras equipped with orthogonal filtrations and under certain assumptions on the form of the twist c…
Convolution semigroups on locally compact quantum groups and noncommutative Dirichlet forms
Adam Skalski, Ami Viselter
The subject of this paper is the study of convolution semigroups of states on a locally compact quantum group, generalising classical families of distributions of a Lévy process on…
Positive Herz-Schur multipliers and approximation properties of crossed products
Andrew McKee, Adam Skalski, Ivan G. Todorov +1
For a -algebra and a set we give a Stinespring-type characterisation of the completely positive Schur -multipliers on . We then relate them t…