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Related papers: On D-spaces and Covering Properties

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The article is devoted to a structure of topological spaces related with topological quasigroups. Regular and complete spaces over topological quasigroups are studied. Separations and embeddings are also investigated for them. Their…

Group Theory · Mathematics 2023-12-29 S. V. Ludkowski

For a number of locally finitely presentable categories K we describe the codensity monad of the full embedding of all finitely presentable objects into K. We introduce the concept of D-ultrafilter on an object, where D is a "nice"…

Category Theory · Mathematics 2020-10-26 Jirí Adámek , Lurdes Sousa

The fundamental groupoid of a space becomes enriched over the category of topological spaces when the hom-sets are endowed with topologies intimately related to universal constructions of topological groups. This paper is devoted to a…

Algebraic Topology · Mathematics 2012-04-30 Jeremy Brazas

We give some basic properties of strongly topologically transitive, supermixing, and hypermixing maps on general topological spaces. Then we present some other results for which our mappings need to be continuous.

Dynamical Systems · Mathematics 2024-01-18 Mahin Ansari , Mohammad Ansari

Based on topological Rudin's Lemma, we investigate two new kinds of sets - Rudin sets and well-filtered determined sets in $T_0$ topological spaces. Using such sets, we formulate and prove some new characterizations for well-filtered spaces…

General Topology · Mathematics 2019-11-27 Xiaoquan Xu , Dongsheng Zhao

We study a natural generalization of covering projections defined in terms of unique lifting properties. A map $p:E\to X$ has the "continuous path-covering property" if all paths in $X$ lift uniquely and continuously (rel. basepoint) with…

Algebraic Topology · Mathematics 2025-01-27 Jeremy Brazas , Atish Mitra

Decomposition spaces are a class of function spaces constructed out of well-behaved coverings and partitions of unity of a set. The structure of the covering of the set determines the properties of the decomposition space. Besov spaces,…

Functional Analysis · Mathematics 2019-04-03 Eirik Berge , Franz Luef

We study geometric and topological properties of locally compact, geodesically complete spaces with an upper curvature bound. We control the size of singular subsets, discuss homotopical and measure-theoretic stratifications and regularity…

Differential Geometry · Mathematics 2018-07-19 Alexander Lytchak , Koichi Nagano

The sum theorem and its corollaries are proved for a countable family of zero-dimensional (in the sense of small and large inductive bidimensions) p-closed sets, using a new notion of relative normality whose topological correspondent is…

General Topology · Mathematics 2007-06-29 B. P. Dvalishvili

The main purpose of this paper is to introduce and study the primal-proximity spaces. Also, we define two new operators via primal proximity spaces and investigate some of their fundamental properties. In addition, we obtain a new topology,…

General Topology · Mathematics 2024-12-20 Ahmad Al-Omari , Murad Ozcog , Santanu Acharjee

Overlays were introduced by R. H. Fox [6] as a subclass of covering maps. We offer a different view of overlays: it resembles the definition of paracompact spaces via star refinements of open covers. One introduces covering structures for…

Algebraic Topology · Mathematics 2013-01-21 Jerzy Dydak

In this paper, we study some properties of $*-$open and $*-$closed subsets of a space. The collection of all $*-$open subsets of a space $X$ form a topology on $X$ which is denoted by $^{*}O(X)$. We investigate the relations between…

General Topology · Mathematics 2023-06-13 Aliakbar Alijani

The design of periodic nanostructures allows to tailor the transport of photons, phonons, and matter waves for specific applications. Recent years have seen a further expansion of this field by engineering topological properties. However,…

Mesoscale and Nanoscale Physics · Physics 2021-06-16 Vittorio Peano , Florian Sapper , Florian Marquardt

In the present survey paper, we present several new classes of Hochster's spectral spaces "occurring in nature", actually in multiplicative ideal theory, and not linked to or realized in an explicit way by prime spectra of rings. The…

Commutative Algebra · Mathematics 2015-10-16 Carmelo A. Finocchiaro , Marco Fontana , Dario Spirito

The open well-filtered spaces were introduced by Shen, Xi, Xu and Zhao to answer the problem whether every core-compact well-filtered space is sober. In the current paper we explore further properties of open well-filtered spaces. One of…

General Topology · Mathematics 2025-02-25 Chong Shen , Xiaoyong Xi , Dongsheng Zhao

We present algorithms for the Max-Cover and Max-Unique-Cover problems in the data stream model. The input to both problems are $m$ subsets of a universe of size $n$ and a value $k\in [m]$. In Max-Cover, the problem is to find a collection…

Data Structures and Algorithms · Computer Science 2021-02-18 Andrew McGregor , David Tench , Hoa T. Vu

We study the set of localizations of an integral domain from a topological point of view, showing that it is always a spectral space and characterizing when it is a proconstructible subspace of the space of all overrings. We then study the…

Commutative Algebra · Mathematics 2018-05-29 Dario Spirito

Classical unsupervised learning methods like clustering and linear dimensionality reduction parametrize large-scale geometry when it is discrete or linear, while more modern methods from manifold learning find low dimensional representation…

Machine Learning · Computer Science 2025-09-23 Luis Scoccola , Uzu Lim , Heather A. Harrington

We develop a unified framework for the study of properties involving diagonalizations of dense families in topological spaces. We provide complete classification of these properties. Our classification draws upon a large number of methods…

General Topology · Mathematics 2012-07-31 Maddalena Bonanzinga , Filippo Cammaroto , Bruno Antonio Pansera , Boaz Tsaban

We define Peano covering maps and prove basic properties analogous to classical covers. Their domain is always locally path-connected but the range may be an arbitrary topological space. One of characterizations of Peano covering maps is…

Geometric Topology · Mathematics 2008-02-14 N. Brodskiy , J. Dydak , B. Labuz , A. Mitra