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Related papers: Quasi-local Algebras and Asymptotic Expanders

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In this paper, we investigate the relationship between semisolidity and locally weak quasisymmetry of homeomorphisms in quasiconvex and complete metric spaces. Our main objectives are to (1) generalize the main result in [X. Huang and J.…

Complex Variables · Mathematics 2015-08-24 Manzi Huang , Antti Rasila , Xiantao Wang , Qingshan Zhou

We introduce asymptotic-M\"obius (AM) maps, a large-scale analogue of quasi-M\"obius maps tailored to geometric group theory. AM-maps capture coarse cross-ratio behavior for configurations of points that lie far apart, providing a notion of…

Metric Geometry · Mathematics 2026-01-13 Georg Grützner

Let $(A, A_o)$ be a topological quasi *-algebra, which means in particular that $A_o$ is a topological *-algebra, dense in $A$. Let $\pi^o$ be a *-representation of $A_o$ in some pre-Hilbert space ${\cal D} \subset {\cal H}$. Then we…

Mathematical Physics · Physics 2009-04-07 J. -P. Antoine , F. Bagarello , C. Trapani

We initiate a study of the quasisymmetric uniformization of naturally arising random fractals and show that many of them fall outside the realm of quasisymmetric uniformization to simple canonical spaces. We begin with the trace, the graph…

Metric Geometry · Mathematics 2024-12-10 Gefei Cai , Wen-Bo Li , Tim Mesikepp

We develop the foundations of the theory of quasi-visual approximations of bounded metric spaces. Roughly speaking, these are sequences of covers of a given space for which the diameters of the sets in the covers shrink to zero and for…

Complex Variables · Mathematics 2026-01-22 Mario Bonk , Mikhail Hlushchanka , Daniel Meyer

We study conditions under which quasi-conformal homeomorphisms are quasi-isometries. We show that if two nilpotent geodesic Lie groups are quasi-conformally homeomorphic, then they are quasi-isometrically equivalent. We also give more…

We formulate an equivalence relation between nonlocal quantum fields, generalizing the relative locality which was studied by Borchers in the framework of local QFT. The Borchers classes are shown to allow a natural extension involving…

Mathematical Physics · Physics 2016-11-23 M. A. Soloviev

Given a discrete and countable inverse semigroup $S$ one can study, in analogy to the group case, its geometric aspects. In particular, we can equip $S$ with a natural metric, given by the path metric in the disjoint union of its…

Operator Algebras · Mathematics 2021-02-08 Fernando Lledó , Diego Martínez

Motivated by the theory of quasi-determinants, we study non-commutative algebras of quasi-Pl\"ucker coordinates. We prove that these algebras provide new examples of non-homogeneous quadratic Koszul algebras by showing that their quadratic…

Rings and Algebras · Mathematics 2020-08-18 Robert Laugwitz , Vladimir Retakh

Quasi *-algebras possessing a sufficient family $\mathcal{M}$ of invariant positive sesquilinear forms carry several topologies related to $\mathcal{M}$ which make every *-representation continuous. This leads to define the class of locally…

Functional Analysis · Mathematics 2023-04-13 Giorgia Bellomonte , Camillo Trapani

We solve the rigidity problem for uniform Roe algebras, by showing that two uniformly locally finite metric spaces with isomorphic uniform Roe algebras are bijectively coarsely equivalent.

Operator Algebras · Mathematics 2026-02-03 Alessandro Vignati

Motivated by coarse geometry and the classical role of Roe algebras as large-scale invariants of proper metric spaces, we show that proper quantum metric spaces as introduced by Latr\'emoli\`ere are noncommutative coarse spaces. This…

Operator Algebras · Mathematics 2026-02-27 Ayoub Hafid

We develop a theory of $\phi$-coordinated (quasi) modules for a nonlocal vertex algebra and we establish a conceptual construction of nonlocal vertex algebras and their $\phi$-coordinated (quasi) modules, where $\phi$ is what we call an…

Quantum Algebra · Mathematics 2010-05-28 Haisheng Li

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

In analogy with the C*-algebra theory, we study variants appropriate to nonselfadjoint algebras of nuclearity, the local lifting property, exactness, and the weak expectation property. In addition, we study the relationships between these…

Operator Algebras · Mathematics 2008-04-02 David P. Blecher , Benton L. Duncan

We study the symmetry properties of the weak positive solutions to a class of quasi-linear elliptic problems having a variational structure. On this basis, the asymptotic behaviour of global solutions of the corresponding parabolic…

Analysis of PDEs · Mathematics 2009-10-09 Luigi Montoro , Berardino Sciunzi , Marco Squassina

We study which von Neumann algebras can be embedded into uniform Roe algebras and quasi-local algebras associated to a uniformly locally finite metric space $X$. Under weak assumptions, these $\mathrm{C}^*$-algebras contain embedded copies…

Operator Algebras · Mathematics 2023-02-20 Florent P. Baudier , Bruno de Mendonça Braga , Ilijas Farah , Alessandro Vignati , Rufus Willett

In this paper, we will define the reduced cross-sectional $C^*$-algebras of $C^*$-algebraic bundles over locally compact groups and show that if a $C^*$-algebraic bundle has the approximation property (defined similarly as in the discrete…

Operator Algebras · Mathematics 2007-05-23 Ruy Exel , Chi-Keung Ng

Uniformity and proximity are two different ways for defining small scale structures on a set. Coarse structures are large scale counterparts of uniform structures. In this paper, motivated by the definition of proximity, we develop the…

Geometric Topology · Mathematics 2021-11-12 Sh. Kalantari , B. Honari

The present paper deals with various aspects of the notion of almost Cohen-Macaulay property, which was introduced and studied by Roberts, Singh and Srinivas. We employ the definition of almost zero modules as defined by a value map, which…

Commutative Algebra · Mathematics 2012-08-28 Mohsen Asgharzadeh , Kazuma Shimomoto