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In this paper, we characterize when the $\ell^p$ uniform Roe algebra of a metric space with bounded geometry is (stably) finite and when it is properly infinite in standard form for $p\in [1,\infty)$. Moreover, we show that the $\ell^p$…

Functional Analysis · Mathematics 2019-04-16 Yeong Chyuan Chung , Kang Li

Given a local Haag-Kastler net of von Neumann algebras and one of its scaling limit states, we introduce a variant of the notion of asymptotic morphism by Connes and Higson, and we show that the unitary equivalence classes of (localized)…

Mathematical Physics · Physics 2015-10-20 Roberto Conti , Gerardo Morsella

In this paper I show that pointwise bounded asymptotic morphisms between separable metrisable locally convex *-algebras induce continuous maps between the quasi-unitary groups of the algebras, provided that the algebras support a certain…

Operator Algebras · Mathematics 2007-05-23 Edwin J. Beggs

We introduce the notion of asymptotic cohomology based on the bounded cohomology and define cohomological asymptotic dimension $\as_{\Z} X$ of metric spaces. We show that it agrees with the asymptotic dimension $\as X$ when the later is…

Metric Geometry · Mathematics 2007-05-23 A. N. Dranishnikov

We prove that uniform Roe C*-algebras associated to some expander graphs coming from discrete groups with property (\tau) are not K-exact. In particular, we show that this is the case for the expander obtained as Cayley graphs of a sequence…

Operator Algebras · Mathematics 2009-07-15 Jan Spakula

Recent research in coarse geometry revealed similarities between certain concepts of analysis, large scale geometry, and topology. Property A of G.Yu is the coarse analog of amenability for groups and its generalization (exact spaces) was…

Metric Geometry · Mathematics 2014-01-07 M. Cencelj , J. Dydak , A. Vavpetič

Let X be a proper metric space, which has finite asymptotic dimension in the sense of Gromov (or more generally, straight finite decomposition complexity of Dranishnikov and Zarichnyi). New descriptions are provided of the Roe algebra of X:…

Operator Algebras · Mathematics 2019-03-06 Jan Spakula , Aaron Tikuisis

The large-scale geometry of hyperbolic metric spaces exhibits many distinctive features, such as the stability of quasi-geodesics (the Morse Lemma), the visibility property, and the homeomorphism between visual boundaries induced by a…

Metric Geometry · Mathematics 2019-01-29 Bruce Kleiner , Urs Lang

Roe algebras are C*-algebras built using large-scale (or 'coarse') aspects of a metric space (X,d). In the special case that X=G is a finitely generated group and d is a word metric, the simplest Roe algebra associated to (G,d) is…

Operator Algebras · Mathematics 2013-09-24 Jan Spakula , Rufus Willett

We generalize the notions of asymptotic dimension and coarse embeddings from metric spaces to quantum metric spaces in the sense of Kuperberg and Weaver. We show that quantum asymptotic dimension behaves well with respect to metric…

Operator Algebras · Mathematics 2020-06-08 Javier Alejandro Chávez-Domínguez , Andrew T. Swift

A uniform Roe corona is the quotient of the uniform Roe algebra of a metric space by the ideal of compact operators. Among other results, we show that it is consistent with ZFC that isomorphism between uniform Roe coronas implies coarse…

Operator Algebras · Mathematics 2021-06-18 Bruno de Mendonça Braga , Ilijas Farah , Alessandro Vignati

In this paper, we introduce relative Roe functors and show that for every pair of scalable proper metric spaces, the functor of continuous functions and the relative Roe functor, both associated with this pair, are asymptotically adjoint.…

Operator Algebras · Mathematics 2025-10-10 Georgii S. Makeev

We study a class of integral functionals known as nonlocal perimeters, which, intuitively, express a weighted interaction between a set and its complement. The weight is provided by a positive kernel K, which might be singular. In the first…

Analysis of PDEs · Mathematics 2020-04-07 Judith Berendsen , Valerio Pagliari

We prove that faithful traces on separable and nuclear C*-algebras in the UCT class are quasidiagonal. This has a number of consequences. Firstly, by results of many hands, the classification of unital, separable, simple and nuclear…

Operator Algebras · Mathematics 2016-12-07 Aaron Tikuisis , Stuart White , Wilhelm Winter

Similar to linear spaces, many examples of quasilinear spaces have a notion of multiplication of the elements. To characterising these examples, in the present paper we generalize the notion of quasilinear spaces and introduce…

Functional Analysis · Mathematics 2020-10-20 Reza Dehghanizade , Seyed Mohamad Sadegh Modarres Mosadegh

The completion of a (normed) $C^*$-algebra $A_0[\| \cdot \|_0]$ with respect to a locally convex topology $\tau$ on $A_0$ that makes the multiplication of $A_0$ separately continuous is, in general, a quasi *-algebra, and not a locally…

Mathematical Physics · Physics 2009-04-07 F. Bagarello , M. Fragoulopoulou , A. Inoue , C. Trapani

The rigidity problem for uniform Roe algebras was recently positively solved. Before its solution was found, there were positive solutions under the assumption of certain technical geometric conditions. In this paper, we introduce weaker…

Operator Algebras · Mathematics 2022-11-08 Bruno M. Braga , Ilijas Farah , Alessandro Vignati

Over a field of characteristic zero, we show that two commutative differential graded (dg) algebras are quasi-isomorphic if and only if they are quasi-isomorphic as associative dg algebras. This answers a folklore problem in rational…

Rings and Algebras · Mathematics 2025-03-17 Ricardo Campos , Dan Petersen , Daniel Robert-Nicoud , Felix Wierstra

We provide a construction of Roe (C*-)algebras of general coarse spaces in terms of coarse geometric modules. This extends the classical theory of Roe algebras of metric spaces and gives a unified framework to deal with either uniform or…

Operator Algebras · Mathematics 2024-04-03 Diego Martínez , Federico Vigolo

In this paper, we study embeddings of uniform Roe algebras. Generally speaking, given metric spaces $X$ and $Y$, we are interested in which large scale geometric properties are stable under embedding of the uniform Roe algebra of $X$ into…

Operator Algebras · Mathematics 2019-06-28 Bruno de Mendonça Braga , Ilijas Farah , Alessandro Vignati