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Related papers: Coarse property {C} and decomposition complexity

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The main purpose of this paper is to study \emph{$e$-separable spaces}, originally introduced by Kurepa as $K_0'$ spaces; we call a space $X$ $e$-separable iff $X$ has a dense set which is the union of countably many closed discrete sets.…

General Topology · Mathematics 2017-06-07 Rodrigo R. Dias , Daniel T. Soukup

We give Ramsey expansions of classes of generalised metric spaces where distances come from a linearly ordered commutative monoid. This complements results of Conant about the extension property for partial automorphisms and extends an…

Combinatorics · Mathematics 2021-07-06 Jan Hubička , Matěj Konečný , Jaroslav Nešetřil

Discrete Morse theory emerged as an essential tool for computational geometry and topology. Its core structures are discrete gradient fields, defined as acyclic matchings on a complex $C$, from which topological and geometrical informations…

Geometric Topology · Mathematics 2018-01-31 Joao Paixao , Joao Lagoas , Thomas Lewiner , Tiago Novello

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

This paper discusses `geometric property (T)'. This is a property of metric spaces introduced in earlier work of the authors for its applications to K-theory. Geometric property (T) is a strong form of `expansion property': in particular…

Metric Geometry · Mathematics 2014-04-28 Rufus Willett , Guoliang Yu

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

$c$-realcompact spaces are introduced by Karamzadeh and Keshtkar in Quaest. Math. 41(8), 2018, 1135-1167. We offer a characterization of these spaces $X$ via $c$-stable family of closed sets in $X$ by showing that $X$ is $c$-realcompact if…

General Topology · Mathematics 2022-02-15 Sudip Kumar Acharyya , Rakesh Bharati , Atasi Deb Ray

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

In this paper we develop an axiomatic approach to coarse homology theories. We prove a uniqueness result concerning coarse homology theories on the category of `coarse CW-complexes'. This uniqueness result is used to prove a version of the…

Algebraic Topology · Mathematics 2014-10-01 Paul D. Mitchener

We prove the strong $C^\infty$ closing property, as formulated by Irie, for a class of Hamiltonian diffeomorphisms which includes all pseudo-rotations of projective spaces as well as all Anosov-Katok pseudo-rotations.

Symplectic Geometry · Mathematics 2023-02-15 Erman Cineli , Sobhan Seyfaddini

Axiomatic Cohesion proposes that the contrast between cohesion and non-cohesion may be expressed by means of a geometric morphism $p :\mathcal{E} \to \mathcal {S}$ (between toposes) with certain special properties that allow to effectively…

Category Theory · Mathematics 2016-02-10 F. Marmolejo , M. Menni

Within the class of reflexive Banach spaces, we prove a metric characterization of the class of asymptotic-$c_0$ spaces in terms of a bi-Lipschitz invariant which involves metrics that generalize the Hamming metric on $k$-subsets of…

Functional Analysis · Mathematics 2020-04-13 Florent P. Baudier , Gilles Lancien , Pavlos Motakis , Thomas Schlumprecht

For a group $G$, we denote by $\stackrel{\leftrightarrow}{G}$ the coarse space on $G$ endowed with the coarse structure with the base $\{\{ (x,y)\in G\times G: y\in x^F \} : F \in [G]^{<\omega} \}$, $x^F = \{z^{-1} xz : z\in F \}$. Our goal…

General Mathematics · Mathematics 2020-12-15 Igor Protasov , Ksenia Protasova

We show that if a subspace $A$ of a coarse $PD(n)$ metric space $X$ coarsely separates it, then it must have asymptotic dimension at least $n-1$.

Metric Geometry · Mathematics 2025-06-27 Harsh Patil

C(X) denotes the space of continuous complex-valued functions on the compact Hausdorff space X. X has the CSWP if every subalgebra of C(X) which separates points and contains the constant functions is dense in C(X). W. Rudin showed that all…

General Topology · Mathematics 2007-05-23 Kenneth Kunen

Sofic groups generalise both residually finite and amenable groups, and the concept is central to many important results and conjectures in measured group theory. We introduce a topological notion of a sofic boundary attached to a given…

Group Theory · Mathematics 2026-04-28 Vadim Alekseev , Martin Finn-Sell

Within a category $\mathtt{C}$, having objects $\mathtt{C}_0$, it may be instructive to know not only that two objects are non-isomorphic, but also how far from being isomorphic they are. We introduce pseudo-metrics $d:\mathtt{C}_0 \times…

Group Theory · Mathematics 2023-04-04 P. A. Brooksbank , J. F. Maglione , E. A. O'Brien , J. B. Wilson

The paper is devoted to one of the important notions of the shape theory: that of strong movability, which was primarily introduced by K. Borsuk for metrizable compacts. A strong movability criterion is proved for topological spaces, which…

Algebraic Topology · Mathematics 2023-08-15 Pavel S. Gevorgyan , T. A. Avakyan

In this paper, we present generalizations of some results on the asymptotic property C for wreath products. Specifically, we prove that certain wreath-like products admit asymptotic property C, thus providing some new examples for further…

Group Theory · Mathematics 2025-12-09 Han Liu

We propose the Roe C*-algebra from coarse geometry as a model for topological phases of disordered materials. We explain the robustness of this C*-algebra and formulate the bulk-edge correspondence in this framework. We describe the map…

Mathematical Physics · Physics 2019-04-30 Eske Ellen Ewert , Ralf Meyer
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