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Related papers: An alternative definition of coarse structures

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We introduce a large scale analogue of the classical fixed-point property for continuous maps, which shall apply to coarse maps. We also develop a coarse version of degree for coarse maps on Euclidean spaces. Then, applying a coarse…

Algebraic Topology · Mathematics 2010-08-31 Steven Hair

We propose to employ the hierarchical coarse-grained structure in the artificial neural networks explicitly to improve the interpretability without degrading performance. The idea has been applied in two situations. One is a neural network…

Machine Learning · Computer Science 2024-06-19 Xi-Ci Yang , Z. Y. Xie , Xiao-Tao Yang

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 cosurfaces with values in the group \(\PC_n(H)\) of \(H\)-valued reciprocal pairwise comparison matrices. The composition law is covariant on upper triangular coefficients and contravariant on lower triangular coefficients,…

General Physics · Physics 2026-05-06 Jean-Pierre Magnot

We study the geometry of warped cones over free, minimal isometric group actions and related constructions of expander graphs. We prove a rigidity theorem for the coarse geometry of such warped cones: Namely, if a group has no abelian…

Metric Geometry · Mathematics 2018-01-09 David Fisher , Thang Nguyen , Wouter van Limbeek

Abstract axiomatic formulation of mathematical structures are extensively used to describe our physical world. We take here the reverse way. By making basic assumptions as starting point, we reconstruct some features of both geometry and…

History and Overview · Mathematics 2021-02-12 B. F. Rizzuti , L. M. Gaio , C. Duarte

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 study notions of generic and coarse computability in the context of computable structure theory. Our notions are stratified by the $\Sigma_\beta$ hierarchy. We focus on linear orderings. We show that at the $\Sigma_1$ level all linear…

Logic · Mathematics 2024-01-29 Wesley Calvert , Douglas Cenzer , David Gonzalez , Valentina Harizanov

A set $X$ endowed with a coarse structure is called ballean or coarse space. For a ballean $(X, \mathcal{E})$, we say that two subsets $A$, $B$ of $X$ are close (linked) if there exists an entourage $E\in \mathcal{E}$ such that $A\subseteq…

General Topology · Mathematics 2020-02-17 Igor Protasov , Ksenia Protasova

We provide a formal introduction into the classic theorems of general topology and its axiomatic foundations in set theory. In this second part we introduce the fundamental concepts of topological spaces, convergence, and continuity, as…

History and Overview · Mathematics 2013-07-01 Felix Nagel

We study countable embedding-universal and homomorphism-universal structures and unify results related to both of these notions. We show that many universal and ultrahomogeneous structures allow a concise description (called here a finite…

Combinatorics · Mathematics 2010-09-06 Jan Hubicka

Hyperspaces form a powerful tool in some branches of mathematics: lots of fractal and other geometric objects can be viewed as fixed points of some functions in suitable hyperspaces - as well as interesting classes of formal languages in…

General Topology · Mathematics 2014-10-15 René Bartsch

In this paper, we define a new structure analogous to group, called partial group. This structure concerns the partial stability by the composition inner law. We generalize the three isomorphism theorems for groups to partial groups.

Group Theory · Mathematics 2013-08-06 Yahya N'Dao , Adlene Ayadi

In recent years a lot of attention has been paid to topological spaces which are a bit more general than smooth manifolds - orbifolds. Orbifolds are intuitively speaking manifolds with some singularities. The formal definition is also…

Differential Geometry · Mathematics 2016-05-16 Robert Wolak

A ballean (or coarse space) is a set endowed with a coarse structure. A ballean $X$ is called normal if any two asymptotically disjoint subsets of $X$ are asymptotically separated. We say that a ballean $X$ is ultranormal (extremely normal)…

General Topology · Mathematics 2019-01-23 Igor Protasov

One considers geometry with the intransitive equaivalence relation. Such a geometry is a physical geometry, i.e. it is described completely by the world function, which is a half of the squared distance function. The physical geometry…

General Mathematics · Mathematics 2009-03-30 Yuri A. Rylov

We develop a theory of rewriting for structured cospans in order to extend compositional methods for modeling open networks. First, we introduce a category whose objects are structured cospans, and establish conditions under which it is…

Category Theory · Mathematics 2026-04-06 Daniel Cicala

In [1] we introduced the notion of 'structured space', i.e. a space which locally resembles various algebraic structures. In [2] and [3] we studied some cohomology theories related to these space. In this paper we continue in this…

Algebraic Topology · Mathematics 2020-05-15 Manuel Norman

We define general notions of coordinate geometries over fields and ordered fields, and consider coordinate geometries that are given by finitely many relations that are definable over those fields. We show that the automorphism group of…

Logic · Mathematics 2025-07-15 Judit Madarász , Mike Stannett , Gergely Székely

Stable fold maps are fundamental tools in a generalization of the theory of Morse functions on smooth manifolds and its application to studies of geometric properties of smooth manifolds. Round fold maps were introduced as stable fold maps…

Algebraic Topology · Mathematics 2019-05-14 Naoki Kitazawa