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Related papers: An alternative definition of coarse structures

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A coarse space $X$, endowed with a linear order compatible with the coarse structure of $X$, is called linearly ordered. We prove that every linearly ordered coarse space $X$ is locally convex and the asymptotic dimension of $X$ is either…

General Topology · Mathematics 2021-10-05 Igor Protasov

We introduce a generalized notion of inference system to support more flexible interpretations of recursive definitions. Besides axioms and inference rules with the usual meaning, we allow also coaxioms, which are, intuitively, axioms which…

Logic in Computer Science · Computer Science 2023-06-22 Francesco Dagnino

Rough set theory is a new mathematical approach to imperfect knowledge. The notion of rough sets is generalized by using an arbitrary binary relation on attribute values in information systems, instead of the trivial equality relation. The…

General Mathematics · Mathematics 2015-02-24 M. Abo-Elhamayel

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

A coarse group is a group endowed with a coarse structure so that the group multiplication and inversion are coarse mappings. Let $(X, \mathcal{E})$ be a coarse space and let $\mathfrak{M}$ be a variety of groups different from the variety…

General Topology · Mathematics 2018-03-29 Igor Protasov , Ksenia Protasova

This paper presents a new version of boundary on coarse spaces. The space of ends functor maps coarse metric spaces to uniform topological spaces and coarse maps to uniformly continuous maps.

Metric Geometry · Mathematics 2019-07-08 Elisa Hartmann

We show how to decompose all separable ultrametric spaces into a "Lego" combinations of scaled versions of full simplices. To do this we introduce metric resolutions of large scale metric spaces, which describe how a space can be broken up…

Metric Geometry · Mathematics 2022-05-13 Yuankui Ma , Jeremy Siegert , Jerzy Dydak

We present an Eilenberg-Steenrod-like axiomatic framework for equivariant coarse homology and cohomology theories. We also discuss a general construction of such coarse theories from topological ones and the associated transgression maps. A…

Algebraic Topology · Mathematics 2022-07-27 Christopher Wulff

We study the notion of geometric structures for toposes: This generalizes the notion of (X,G) manifolds. We give some applications to algebraic geometry

Differential Geometry · Mathematics 2007-05-23 A Tsemo

We prove that uniformly locally finite metric spaces with isomorphic Roe algebras must be coarsely equivalent. As an application, we also prove that the outer automorphism group of the Roe algebra of a metric space of bounded geometry is…

Operator Algebras · Mathematics 2025-03-10 Diego Martínez , Federico Vigolo

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

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 simple and entirely algebraic notion of coarse median algebra…

Metric Geometry · Mathematics 2020-06-30 Graham A. Niblo , Nick Wright , Jiawen Zhang

We introduce properties of metric spaces and, specifically, finitely generated groups with word metrics which we call coarse coherence and coarse regular coherence. They are geometric counterparts of the classical algebraic notion of…

K-Theory and Homology · Mathematics 2020-02-17 Boris Goldfarb , Jonathan L. Grossman

We study embeddings of uniform Roe algebras which have "large range" in their codomain and the relation of those with coarse quotients between metric spaces. Among other results, we show that if $Y$ has property A and there is an embedding…

Operator Algebras · Mathematics 2021-08-27 Bruno de Mendonça Braga

For every strong coarse homology theory we construct a coarse assembly map as a natural transformation between coarse homology theories. We provide various conditions implying that this assembly map is an equivalence. These results…

K-Theory and Homology · Mathematics 2020-08-26 Ulrich Bunke , Alexander Engel

We construct secondary cup and cap products on coarse (co-)homology theories from given cross and slant products. They are defined for coarse spaces relative to weak generalized controlled deformation retracts. On ordinary coarse…

Algebraic Topology · Mathematics 2021-09-15 Christopher Wulff

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

The objective of this paper is to explain the principles of the design of a coarse space in a simplified way and by pictures. The focus is on ideas rather than on a more historically complete presentation. Also, space limitation does not…

Numerical Analysis · Mathematics 2014-07-17 Jan Mandel , Bedřich Sousedík

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

A group, defined as set with associative multiplication and inverse, is a natural structure describing the symmetry of a space. The concept of group generalizes to group objects internal to other categories than sets. But there are yet more…

Symplectic Geometry · Mathematics 2007-05-23 Christian Blohmann , Alan Weinstein