activity
20152026
most citedA quasi-local characterisation of -Roe algebras

11 citations · 33 across the 23 of their papers we have counts for

collaborators

23 papers

math.OA2026

-Theoretic Comparison of Roe and Quasi-Local Algebras via Projections

Kang Li, Jiawen Zhang, Jingming Zhu

A central question in higher index theory and operator algebras is whether the Roe algebra and the quasi-local algebra associated with a metric space of bounded geometry coincide,…

math.MG2023

Examples of hyperbolic spaces without the properties of quasi-ball or bounded eccentricity

Qizheng You, Jiawen Zhang

In this note, we present examples of non-quasi-geodesic metric spaces which are hyperbolic (i.e., satisfying the Gromov's -point condition) while the intersection of any two met…

math.OA2023

Rigidity for geometric ideals in uniform Roe algebras

Baojie Jiang, Jiawen Zhang

In this paper, we investigate the rigidity problems for geometric ideals in uniform Roe algebras associated to discrete metric spaces of bounded geometry. These ideals were introdu…

math.OA2023

Ghostly ideals in uniform Roe algebras

Qin Wang, Jiawen Zhang

In this paper, we investigate the ideal structure of uniform Roe algebras for general metric spaces beyond the scope of Yu's property A. Inspired by the ideal of ghost operators co…

math.MG2022

Characterisations for uniform amenability

Jingming Zhu, Jiawen Zhang

In this paper, we provide several characterisations for uniform amenability concerning a family of finitely generated groups. More precisely, we show that the Hulanicki-Reiter cond…

math.OA2022

The equivariant coarse Baum-Connes conjecture for actions by a-T-menable groups

Benyin Fu, Jiawen Zhang

The equivariant coarse Baum-Connes conjecture was firstly introduced by Roe [29] as a unified way to approach both the Baum-Connes conjecture and its coarse counterpart. In this pa…

math.OA2021

The strongly quasi-local coarse Novikov conjecture and Banach spaces with Property (H)

Xiaoman Chen, Kun Gao, Jiawen Zhang

In this paper, we introduce a strongly quasi-local version of the coarse Novikov conjecture, which states that certain assembly map from the coarse -homology of a metric space t…

math.OA2021

Strongly Quasi-local algebras and their -theories

Hengda Bao, Xiaoman Chen, Jiawen Zhang

In this paper, we introduce a notion of strongly quasi-local algebras. They are defined for each discrete metric space with bounded geometry, and sit between the Roe algebra and th…

math.MG2021

Measured expanders

Kang Li, Ján Špakula, Jiawen Zhang

By measured graphs we mean graphs endowed with a measure on the set of vertices. In this context, we explore the relations between the appropriate Cheeger constant and Poincaré ine…

math.OA2020

Measured asymptotic expanders and rigidity for Roe algebras

Kang Li, Ján Špakula, Jiawen Zhang

Our main result about rigidity of Roe algebras is the following: if and are metric spaces with bounded geometry such that their Roe algebras are -isomorphic, then an…

math.DS2020★ 4 cited

A Markovian and Roe-algebraic approach to asymptotic expansion in measure

Kang Li, Federico Vigolo, Jiawen Zhang

In this paper, we conduct further studies on geometric and analytic properties of asymptotic expansion in measure. More precisely, we develop a machinery of Markov expansion and ob…

math.DS2020★ 1 cited

Asymptotic expansion in measure and strong ergodicity

Kang Li, Federico Vigolo, Jiawen Zhang

In this paper, we introduce and study a notion of asymptotic expansion in measure for measurable actions. This generalises expansion in measure and provides a new perspective on th…

math.MG2019★ 1 cited

On the structure of asymptotic expanders

Ana Khukhro, Kang Li, Federico Vigolo +1

In this paper, we use geometric tools to study the structure of asymptotic expanders and show that a sequence of asymptotic expanders always admits a "uniform exhaustion by expande…

math.OA2019★ 4 cited

Quasi-local Algebras and Asymptotic Expanders

Kang Li, Piotr Nowak, Ján Špakula +1

In this paper, we study the relation between the uniform Roe algebra and the uniform quasi-local algebra associated to a metric space of bounded geometry. In the process, we introd…

math.OA2019★ 1 cited

Limit operator theory for groupoids

Kyle Austin, Jiawen Zhang

We extend the symbol calculus and study the limit operator theory for -compact, étale and amenable groupoids, in the Hilbert space case. This approach not only unifies various e…

math.FA2018★ 4 cited

Quasi-Locality and Property A

Ján Špakula, Jiawen Zhang

Let be a metric space with bounded geometry, , and let be a Banach space. The main result of this paper is that either if has Yu's Property A…

math.FA2018★ 1 cited

Extreme cases of limit operator theory on metric spaces

Jiawen Zhang

The theory of limit operators was developed by Rabinovich, Roch and Silbermann to study the Fredholmness of band-dominated operators on for $p \in \{0\} \cup…

math.FA2018★ 11 cited

A quasi-local characterisation of -Roe algebras

Kang Li, Zhijie Wang, Jiawen Zhang

Very recently, Špakula and Tikuisis provide a new characterisation of (uniform) Roe algebras via quasi-locality when the underlying metric spaces have straight finite decomposition…

math.MG2018★ 1 cited

Coarse median algebras: The intrinsic geometry of coarse median spaces and their intervals

Graham A. Niblo, Nick Wright, Jiawen Zhang

This paper establishes a new combinatorial framework for the study of coarse median spaces, bridging the worlds of asymptotic geometry, algebra and combinatorics. We introduce a si…

math.MG2017★ 2 cited

A four point characterisation for coarse median spaces

Graham A. Niblo, Nick Wright, Jiawen Zhang

Coarse median spaces simultaneously generalise the classes of hyperbolic spaces and median algebras, and arise naturally in the study of the mapping class groups and many other con…

math.MG2017★ 3 cited

A characterization for asymptotic dimension growth

Goulnara Arzhantseva, Graham A. Niblo, Nick Wright +1

We give a characterization for asymptotic dimension growth. We apply it to CAT(0) cube complexes of finite dimension, giving an alternative proof of N. Wright's result on their fin…

math.GR2015

Large scale properties for bounded automata groups

Xiaoman Chen, Jiawen Zhang

In this paper, we study some large scale properties of the mother groups of bounded automata groups. First we give two methods to prove every mother group has infinite asymptotic d…

math.GT2015

Equi-variant and Stable Finite Decomposition Complexity

Jiawen Zhang

In this paper, we introduce and study various kinds of decomposition complexity. First, we give a characterization of residually finite groups having finite decomposition complexit…