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Related papers: Some counterexamples in abstract coarse geometry

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We introduce an alternative description of coarse proximities. We define a coarse normality condition for connected coarse spaces and show that this definition agrees with large scale normality defined in [3] and asymptotic normality…

General Topology · Mathematics 2019-03-04 Pawel Grzegrzolka , Jeremy Siegert

We define coarse proximity structures, which are an analog of small-scale proximity spaces in the large-scale context. We show that metric spaces induce coarse proximity structures, and we construct a natural small-scale proximity…

Metric Geometry · Mathematics 2024-04-16 Pawel Grzegrzolka , Jeremy Siegert

We consider asymptotic dimension of coarse spaces. We analyse coarse structures induced by metrisable compactifications. We calculate asymptotic dimension of coarse cell complexes. We calculate the asymptotic dimension of certain negatively…

Metric Geometry · Mathematics 2007-05-23 Bernd Grave

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

We construct the first example of a coarsely non-amenable (= without Guoliang Yu's property A) metric space with bounded geometry which coarsely embeds into a Hilbert space.

Group Theory · Mathematics 2011-11-02 Goulnara Arzhantseva , Erik Guentner , Jan Spakula

Using ideas from shape theory we embed the coarse category of metric spaces into the category of direct sequences of simplicial complexes with bonding maps being simplicial. Two direct sequences of simplicial complexes are equivalent if one…

Metric Geometry · Mathematics 2016-02-24 M. Cencelj , J. Dydak , A. Vavpeti\v\{c} , \v\{Z}. Virk

We introduce a notion of equivariant coarse cohomology of the complement of a subspace in a metric space. We use this cohomology to define a notion of coarse cohomology of the configuration space of a metric space and develop tools to…

Metric Geometry · Mathematics 2025-11-05 Arka Banerjee

We introduce a new variant of the coarse Baum-Connes conjecture designed to tackle coarsely disconnected metric spaces called the boundary coarse Baum-Connes conjecture. We prove this conjecture for many coarsely disconnected spaces that…

K-Theory and Homology · Mathematics 2014-07-23 Martin Finn-Sell , Nick Wright

We use compactifications of C*-algebras to introduce noncommutative coarse geometry. We transfer a noncommutative coarse structure on a C*-algebra with an action of a locally compact Abelian group by translations to Rieffel deformations and…

Operator Algebras · Mathematics 2016-10-28 Tathagata Banerjee , Ralf Meyer

We begin the study the algebraic topology of semi-coarse spaces, which are generalizations of coarse spaces that enable one to endow non-trivial `coarse-like' structures to compact metric spaces, something which is impossible in coarse…

Algebraic Topology · Mathematics 2024-10-01 Antonio Rieser , Jonathan Treviño-Marroquín

We introduce the group-compact coarse structure on a Hausdorff topological group in the context of coarse structures on an abstract group which are compatible with the group operations. We develop asymptotic dimension theory for the…

Geometric Topology · Mathematics 2012-01-24 Andrew Nicas , David Rosenthal

We introduce the notion of coarse metric. Every coarse metric induces a coarse structure on the underlying set. Conversely, we observe that all coarse spaces come from a particular type of coarse metric in a unique way. In the case when the…

Metric Geometry · Mathematics 2020-12-15 Chi-Keung Ng

We characterize 1-complemented subspaces of finite codimension in strictly monotone one-$p$-convex, $2<p<\infty,$ sequence spaces. Next we describe, up to isometric isomorphism, all possible types of 1-unconditional structures in sequence…

Functional Analysis · Mathematics 2016-09-06 Beata Randrianantoanina

Bredon has constructed a 2-dimensional compact cohomology manifold which is not homologically locally connected, with respect to the singular homology. In the present paper we construct infinitely many such examples (which are in addition…

Algebraic Topology · Mathematics 2008-05-14 Umed H. Karimov , Dušan Repovš

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 describe a construction (the `warped cone construction') which produces examples of coarse spaces with large groups of translations. We show that by this construction we can obtain many examples of coarse spaces which do not have…

General Topology · Mathematics 2014-11-11 John Roe

Coarse geometry studies metric spaces on the large scale. Our goal here is to study dynamics from a coarse point of view. To this end we introduce a coarse version of topological entropy, suitable for unbounded metric spaces, consistent…

Dynamical Systems · Mathematics 2020-04-20 William Geller , Michał Misiurewicz

We prove that the coarse assembly maps for proper metric spaces which are non-positively curved in the sense of Busemann are isomorphisms, where we do not assume that the spaces are with bounded coarse geometry. Also it is shown that we can…

K-Theory and Homology · Mathematics 2018-10-23 Tomohiro Fukaya , Shin-ichi Oguni

We show that the connected sum of two copies of real projective 3-space does not admit a real projective structure. This is the first known example of a connected 3-manifold without a real projective structure.

Geometric Topology · Mathematics 2015-01-06 Daryl Cooper , William Goldman

In this note on coarse geometry we revisit coarse homotopy. We prove that coarse homotopy indeed is an equivalence relation, and this in the most general context of abstract coarse structures. We introduce (in a geometric way) coarse…

Geometric Topology · Mathematics 2023-08-14 Paul D. Mitchener , Behnam Norouzizadeh , Thomas Schick
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