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Related papers: More localized automorphisms of the Cuntz algebras

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We initiate a detailed and systematic study of automorphisms of the Cuntz algebras $\O_n$ which preserve both the diagonal and the core $UHF$-subalgebra. A general criterion of invertibility of endomorphisms yielding such automorphisms is…

Operator Algebras · Mathematics 2011-10-21 Roberto Conti , Wojciech Szymanski

This mainly expository article is devoted to recent advances in the study of dynamical aspects of the Cuntz algebras O_n, with n finite, via their automorphisms and, more generally, endomorphisms. A combinatorial description of permutative…

Operator Algebras · Mathematics 2012-08-16 Roberto Conti , Jeong Hee Hong , Wojciech Szymanski

We survey recent results on endomorphisms and especially on automorphisms of the Cuntz algebras O_n, with a special emphasis on the structure of the Weyl group. We discuss endomorphisms globally preserving the diagonal MASA and their…

Operator Algebras · Mathematics 2011-08-04 Roberto Conti , Wojciech Szymanski

Permutative automorphisms of the Cuntz algebras $\mathcal{O}_n$ are in bijection with the stable permutations of $[n]^t$. They are also the elements of the reduced Weyl group of $Aut(\mathcal{O}_n)$. In this paper, we characterize the…

Operator Algebras · Mathematics 2025-07-25 Junyao Pan

It is shown that, modulo the automorphisms which fix the canonical diagonal MASA point-wise, the group of those automorphisms of the Cuntz algebra O_n which globally preserve both the diagonal and the core UHF-subalgebra is isomorphic, via…

Operator Algebras · Mathematics 2012-08-16 Roberto Conti , Jeong Hee Hong , Wojciech Szymanski

We investigate the structure of the fixed-point algebra of $\mathcal{O}_n$ under the action of the cyclic permutation of the generating isometries. We prove that it is $*$-isomorphic with $\mathcal{O}_n$, thus generalizing a result of Choi…

Operator Algebras · Mathematics 2021-08-03 Valeriano Aiello , Stefano Rossi

Automorphisms of the canonical core UHF-subalgebra F_n of the Cuntz algebra O_n do not necessarily extend to automorphisms of O_n. Simple examples are discussed within the family of infinite tensor products of (inner) automorphisms of the…

Operator Algebras · Mathematics 2011-04-12 Roberto Conti

Permutative automorphisms of the Cuntz algebras $\mathcal{O}_n$ are in bijection with the stable permutations of $[n]^k$. They are also the elements of the restricted Weyl group of $Aut(\mathcal{O}_n)$. In this note, we characterize a class…

Group Theory · Mathematics 2025-11-04 Junyao Pan

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

The Weyl group of the Cuntz algebra O_n, with n finite, is investigated. This is (isomorphic to) the group of polynomial automorphisms of O_n, namely those induced by unitaries that can be written as finite sums of words in the canonical…

Operator Algebras · Mathematics 2013-01-11 Roberto Conti , Jeong Hee Hong , Wojciech Szymanski

We study the automorphism group of the algebra $\oqmn$ of $n \times n$ generic quantum matrices. We provide evidence for our conjecture that this group is generated by the transposition and the subgroup of those automorphisms acting on the…

Quantum Algebra · Mathematics 2013-04-26 S. Launois , T. H. Lenagan

In this article, we explore the quantum symmetry of the direct sum of a finite family of Cuntz algebras $\{\mathcal{O}_{n_i} \}_{i=1}^{m}$, viewing them as graph $C^*$-algebras associated to the graphs $\{L_{n_i}\}_{i=1}^{m}$ (where $L_n$…

Operator Algebras · Mathematics 2025-12-03 Ujjal Karmakar , Arnab Mandal

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

We investigate the structure of the outer automorphism group of the Cuntz algebra and the closely related problem of conjugacy of MASAa in O_n. In particular, we exhibit an uncountable family of MASAs, conjugate to the standard MASA D_n via…

Operator Algebras · Mathematics 2015-10-20 Roberto Conti , Jeong Hee Hong , Wojciech Szymanski

We investigate the relationship between endomorphisms of the Cuntz algebra ${\mathcal O}_2$ and endomorphisms of the Thompson groups $F$, $T$ and $V$ represented inside the unitary group of ${\mathcal O}_2$. For an endomorphism $\lambda_u$…

Operator Algebras · Mathematics 2017-10-24 Selçuk Barlak , Jeong Hee Hong , Wojciech Szymanski

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

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

We investigate the structure of the automorphism of $\mathcal{O}_{2}$ which exchanges the two canonical isometries. Our main observation is that the fixed point C*-subalgebra for this action is isomorphic to $\mathcal{O}_{2}$ and we detail…

Operator Algebras · Mathematics 2011-11-04 Man-Duen Choi , Frederic Latremoliere

Extending early work, we formulate the large N matrix mechanics of general bosonic, fermionic and supersymmetric matrix models, including Matrix theory: The Hamiltonian framework of large N matrix mechanics provides a natural setting in…

High Energy Physics - Theory · Physics 2014-11-18 M. B. Halpern , C. Schwartz

We initiate a systematic investigation of endomorphisms of graph C*-algebras C*(E), extending several known results on endomorphisms of the Cuntz algebras O_n. Most but not all of this study is focused on endomorphisms which permute the…

Operator Algebras · Mathematics 2013-01-11 Roberto Conti , Jeong Hee Hong , Wojciech Szymanski
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