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Related papers: C*-algebras and their nuclear dimension

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In arXiv:math/0603621 we introduced the notion of a partial translation $C^*$-algebra for a discrete metric space. Here we demonstrate that several important classical $C^*$-algebras and extensions arise naturally by considering partial…

Operator Algebras · Mathematics 2008-04-04 J. Brodzki , G. A. Niblo , N. J. Wright

Let $\Omega$ be a class of unital ${\rm C^*}$-algebras which have the second type tracial nuclear dimensional at moat $n$ (or have tracial nuclear dimensional at most $n$). Let $A$ be an infinite dimensional unital simple ${\rm…

Operator Algebras · Mathematics 2023-05-09 Qingzhai Fan , Jiahui Wang

Order unit property of a positive element in a $C^{*}$-algebra is defined. It is proved that precisely projections satisfy this order theoretic property. This way, unital hereditary $C^{*}$-subalgebras of a $C^{*}$-algebra are…

Operator Algebras · Mathematics 2007-05-23 Anil K. Karn

We exhibit a unital simple nuclear non-type-I C*-algebra into which the Jiang-Su algebra does not embed unitally. This answers a question of M. R{\o}rdam.

Operator Algebras · Mathematics 2007-12-13 Marius Dadarlat , Ilan Hirshberg , Andrew S. Toms , Wilhelm Winter

We define the class of weakly approximately divisible unital C*-algebras and show that this class is closed under direct sums, direct limits, any tensor product with any C*-algebra, and quotients. A nuclear C*-algebra is weakly…

Operator Algebras · Mathematics 2019-02-20 Don Hadwin , Weihua Li

Complexity rank for $C^*$-algebras was introduced by the second author and Yu for applications towards the UCT: very roughly, this rank is at most $n$ if you can repeatedly cut the $C^*$-algebra in half at most $n$ times, and end up with…

Operator Algebras · Mathematics 2022-10-13 Arturo Jaime , Rufus Willett

We investigate $^*$-homomorphisms with nuclear dimension equal to zero. In the framework of classification of $^*$-homo-morphisms, we characterise such maps as those that can be approximately factorised through an AF-algebra. Along the way,…

Operator Algebras · Mathematics 2024-07-02 Jorge Castillejos , Robert Neagu

This talk reviews some mathematical and physical ideas related to the notion of dimension. After a brief historical introduction, various modern constructions from fractal geometry, noncommutative geometry, and theoretical physics are…

Algebraic Geometry · Mathematics 2007-05-23 Yuri I. Manin

We provide examples of ambient nuclear C*-algebras of non-nuclear C*-algebras with no proper intermediate C*-algebras. In particular this gives the first examples of minimal ambient nuclear C*-algebras of non-nuclear C*-algebras. For this…

Operator Algebras · Mathematics 2016-09-20 Yuhei Suzuki

For a C*-algebra A, G. Pedersen defined the concept of universal measurability for self-adjoint elements of A**, the universal enveloping algebra of A. Although he was unable to show that U, the set of universally measurable elements, is a…

Operator Algebras · Mathematics 2017-06-09 Lawrence G. Brown

In this paper, we study the non-Newtonian version of C-algebras. Further, we generalize some results which hold for the classical C-algebras. We also discuss some illustrative examples to show accuracy and effectiveness of the new findings.…

Rings and Algebras · Mathematics 2021-07-16 Nilay Değirmen

We propose a general scheme for the "logic" of elementary propositions of physical systems, encompassing both classical and quantum cases, in the framework given by Non Commutative Geometry. It involves Baire*-algebras, the non-commutative…

Quantum Physics · Physics 2007-05-23 P. A. Marchetti , R. Rubele

We provide a self-contained proof of the Artin-Wedderburn theorem in the case of finite-dimensional Von Neumann algebras (or equivalently unital C* algebras) that is fully constructive and uses only basic notions of linear algebra.

Rings and Algebras · Mathematics 2025-07-15 Octave Mestoudjian , Pablo Arrighi

For elements $a, b$ of a C*-algebra we denote $a=ab$ by $a\ll b$. We show that all $\omega_1$-unital C*-algebras have $\ll$-increasing approximate units, extending a classical result for $\sigma$-unital C*-algebras. We also construct (in…

Operator Algebras · Mathematics 2019-11-19 Tristan Bice , Piotr Koszmider

We solve a class of lifting problems involving approximate polynomial relations (soft polynomial relations). Various associated C*-algebras are therefore projective. The technical lemma we need is a new manifestation of Akemann and…

Operator Algebras · Mathematics 2014-01-14 Terry A. Loring , Tatiana Shulman

We give a definition of partition C*-algebras: To any partition of a finite set, we assign algebraic relations for a matrix of generators of a universal C*-algebra. We then prove how certain relations may be deduced from others and we…

Operator Algebras · Mathematics 2017-10-18 Moritz Weber

A new category of topological spaces with additional structures, called m-towers, is introduced. It is shown that there is a covariant functor which establishes a one-to-one correspondences between unital (resp. arbitrary) subhomogeneous…

Operator Algebras · Mathematics 2013-10-22 Piotr Niemiec

We give a number of new characterizations of the Jiang-Su algebra Z, both intrinsic and extrinsic, in terms of C*-algebraic, dynamical, topological and K-theoretic conditions. Along the way we study divisibility properties of C*-algebras,…

Operator Algebras · Mathematics 2008-01-16 Mikael Rordam , Wilhelm Winter

We introduce the concept of Rokhlin dimension for actions of residually finite groups on C*-algebras, extending previous notions of Rokhlin dimension for actions of finite groups and the integers, as introduced by Hirshberg, Winter and the…

Operator Algebras · Mathematics 2022-02-22 Gabor Szabo , Jianchao Wu , Joachim Zacharias

C*-algebras are rings, sometimes nonunital, obeying certain axioms that ensure a very well-behaved representation theory upon Hilbert space. Moreover, there are some well-known features of the representation theory leading to subtle…

Operator Algebras · Mathematics 2023-07-07 Cristian Ivanescu , Dan Kucerovsky