English
Related papers

Related papers: Endomorphisms of the Cuntz Algebras

200 papers

We outline the proof of a conjecture of Kontsevich on the isomorphism between the group of polynomial symplectomorphisms in $2n$ variables and the group of automorphisms of the $n$-th Weyl algebra over complex numbers. Our proof uses…

Rings and Algebras · Mathematics 2018-02-06 Alexei Kanel-Belov , Andrey Elishev , Jie-Tai Yu

Cuntz algebras $\mathcal{O}_n$, $n>1$, are celebrated examples of a separable infinite simple C*-algebra with a number of fascinating properties. Their K-theory allows an embedding of $\mathcal O_m$ in $\mathcal O_n$ whenever $n-1$ divides…

Operator Algebras · Mathematics 2025-02-21 Piotr M. Hajac , Yang Liu

We develop some tools, of an algebraic and combinatorial nature, which enable us to obtain a detailed description of certain quadratic subgroups of the (outer) reduced Weyl group of the Cuntz algebra ${\mathcal O}_n$. In particular, for…

Operator Algebras · Mathematics 2026-01-21 Francesco Brenti , Roberto Conti , Gleb Nenashev

The $2$-adic ring $C^*$-algebra $\mathcal{Q}_2$ naturally contains a copy of the Cuntz algebra $\mathcal{O}_2$ and, a fortiori, also of its diagonal subalgebra $\mathcal{D}_2$ with Cantor spectrum. This paper is aimed at studying the group…

Operator Algebras · Mathematics 2018-09-12 Valeriano Aiello , Roberto Conti , Stefano Rossi

Automorphisms of the quantum Schubert cell algebras ${\mathcal U}_q^\pm[w]$ of De Concini, Kac, Procesi and Lusztig and their restrictions to some key invariant subalgebras are studied. We develop some general rigidity results and apply…

Quantum Algebra · Mathematics 2023-02-24 Garrett Johnson , Hayk Melikyan

In the theory of C*-algebras, the Weyl groups were defined for the Cuntz algebras and graph algebras by Cuntz and Conti et al. respectively. In this paper, we introduce and investigate the Weyl groups of groupoid C*-algebras as a natural…

Operator Algebras · Mathematics 2025-01-30 Fuyuta Komura

The automorphism groups ${\rm Aut\,}A_n$ and ${\rm Aut\,}W_n$ of the polynomial algebra $A_n=C[x_1,x_2,\cdots, x_n]$ and the rank $n$ Witt algebra $W_n={\rm Der\,}A_n$ are studied in this paper. It is well-known that ${\rm Aut\,}A_n$ for…

Quantum Algebra · Mathematics 2015-02-06 Jianzhi Han , Yucai Su

We analyze the structure of co-invariant subspaces for representations of the Cuntz algebras O_N for N = 2,3,..., N < infinity, with special attention to the representations which are associated to orthonormal and tight-frame wavelets in…

Operator Algebras · Mathematics 2007-05-23 Palle E. T. Jorgensen

Let O_d be the Cuntz algebra on generators S_1,...,S_d, 2 \leq d < \infty, and let D_d \subset O_d be the abelian subalgebra generated by monomials S_\alpha S_\alpha^* =S_{\alpha_{1}}...S_{\alpha_{k}}S_{\alpha_{k}}^*...S_{\alpha_{1}}^*…

Operator Algebras · Mathematics 2007-05-23 Ola Bratteli , Palle E. T. Jorgensen , Vasyl Ostrovskyi

In this paper, we initiate the study of endomorphisms and modular theory of the graph C*-algebras $\O_{\theta}$of a 2-graph $\Fth$ on a single vertex. We prove that there is a semigroup isomorphism between unital endomorphisms of…

Operator Algebras · Mathematics 2009-10-10 Dilian Yang

We study a class of representations of the Cuntz algebras O_N, N=2,3,..., acting on L^2(T) where T=R/2\pi Z. The representations arise in wavelet theory, but are of independent interest. We find and describe the decomposition into…

funct-an · Mathematics 2008-02-03 Ola Bratteli , Palle E. T. Jorgensen

Let $G$ be a group. The directed endomorphism graph, $\dend(G)$ of $G$ is a directed graph with vertex set $G$ and there is a directed edge from the vertex $a$ to the vertex $b$ if $a \neq b$ and there exists an endomorphism on $G$ mapping…

Group Theory · Mathematics 2025-11-20 Midhuna V Ajith , Peter J Cameron , Mainak Ghosh , Aparna Lakshmanan S

In this work we are going to study the dynamics of the linear automorphisms of a measure convolution algebra over a finite group, $T(\mu)=\nu * \mu$. In order to understand an classify the asymptotic behavior of this dynamical system we…

Dynamical Systems · Mathematics 2014-04-28 Alexandre Baraviera , Elismar R. Oliveira , Fagner B. Rodrigues

Extending the work of Cuntz and Vershik, we develop a general notion of independence for commuting group endomorphisms. Based on this concept, we initiate the study of irreversible algebraic dynamical systems, which can be thought of as…

Operator Algebras · Mathematics 2016-11-04 Nicolai Stammeier

Combinatorial Hantzsche-Wendt groups were introduced by W. Craig and P.A. Linnell. Every such a group $G_n$, where $n$ is a natural number, encodes the holonomy action of any $n+1$-dimensional Hantzsche-Wendt manifold. $G_2$ is the…

Group Theory · Mathematics 2024-01-17 Rafał Lutowski , Andrzej Szczepański , Richard Weidmann

In this paper we exploit the fact that a Cuntz C$^*$-algebra is a groupoid C$^*$-algebra to facilitate the study of non-self-adjoint subalgebras of $O_n$. The Cuntz groupoid is not principal and the spectral theorem for bimodules does not…

Operator Algebras · Mathematics 2007-05-23 Alan Hopenwasser , Justin R. Peters

We show that the representations of the Cuntz C$^\ast$-algebras $O_n$ which arise in wavelet analysis and dilation theory can be classified through a simple analysis of completely positive maps on finite-dimensional space. Based on this…

Operator Algebras · Mathematics 2007-05-23 David W. Kribs

We compute the dynamic asymptotic dimension of the principal groupoid models for the Cuntz algebras $\mathcal{O}_k$ for $2 \leq k < \infty$ that have arisen from work of Winter and the authors. Our method generalises to a wide class of…

Operator Algebras · Mathematics 2025-12-02 Samuel Evington , Philipp Sibbel

To a representation of $\O_N$ (the Cuntz algebra with $N$ generators) we associate a projection valued measure and we study the case when this measure has atoms. The main technical tool are the spaces invariant for all the operators…

Operator Algebras · Mathematics 2013-11-22 Dorin Ervin Dutkay , John Haussermann , Palle E. T. Jorgensen

Based on the fact that the Cuntz algebra $O_n$ is generated by the operators consisting of a finite operatorional partition, we study the notion of operational extreme points (which we introduce here) by using several completely positive…

Operator Algebras · Mathematics 2016-11-15 Marie Choda