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Related papers: Extremally $T_1$-spaces and Related Spaces

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The notions of compactness and Hausdorff separation for generalized enriched categories allow us, as classically done for the category $\mathsf{Top}$ of topological spaces and continuous functions, to study $\textit{compactly generated…

Category Theory · Mathematics 2019-08-13 Willian Ribeiro

We define a notion of (one-sided) edge shift spaces associated to ultragraphs. In the finite case our notion coincides with the edge shift space of a graph. In general, we show that our space is metrizable and has a countable basis of…

Operator Algebras · Mathematics 2017-05-19 Daniel Gonçalves , Danilo Royer

We prove under ZFC that in each extremally disconnected compact space there exists a non-limit point of any countable discrete subset.

General Topology · Mathematics 2023-05-11 Joanna Jureczko

The aim of these lecture notes is, after having quickly described various compactifications of the Teichm\"{u}ller space of a compact connected oriented surface minus finitely many points, to give a construction, by the equivariant Gromov…

Complex Variables · Mathematics 2016-08-16 Frédéric Paulin

The aim of this work is to introduce and study some new types of generalizations of pairwise paralindeloff spaces, pairwise nearly paralindeloff and almost paralindeloff spaces. Some of their characterizations, properties and subsets are…

General Topology · Mathematics 2015-01-05 Hend Bouseliana , Adem Kilicman

A topological space $X$ is called almost discretely Lindel\"of if every discrete set $D \subset X$ is included in a Lindel\"of subspace of $X$. We say that the space $X$ is {\em $\mu$-sequential} if for every non-closed set $A \subset X$…

General Topology · Mathematics 2016-12-21 István Juhász , Lajos Soukup , Zoltán Szentmiklóssy

By a closure space we will mean a pair $(A,\mathcal{C})$, in which $A$ is a set and $\mathcal{C}$ a set of subsets of $A$ closed under arbitrary intersections. The purpose of this paper is to initiate a development of descent theory of…

Category Theory · Mathematics 2023-10-26 George Janelidze , Manuela Sobral

A space is od-compact (resp. od-Lindel\"of) provided any cover by open dense sets has a finite (resp. countable) subcover. We first show with simple examples that these properties behave quite poorly under finite or countable unions. We…

General Topology · Mathematics 2015-03-24 Mathieu Baillif

We study finite systems of subspaces of a complex Hilbert space such that each pair of subspaces satisfies a certain condition as described in the following. For each subspace excepting the first one an angle between this subspace and the…

Functional Analysis · Mathematics 2012-01-18 Ivan Feshchenko , Alexander Strelets

We study geometrically finite one-dimensional mappings. These are a subspace of $C^{1+\alpha}$ one-dimensional mappings with finitely many, critically finite critical points. We study some geometric properties of a mapping in this subspace.…

Dynamical Systems · Mathematics 2008-02-03 Yunping Jiang

Torelli space (in genus g) is the moduli space of compact Riemann surfaces of genus g together with a symplectic basis of their first homology group. It is the quotient of the genus g Teichmuller space by the Torelli group T_g and is a…

Geometric Topology · Mathematics 2007-05-23 Richard Hain

In this paper we introduce a new technique to prove the existence of closed subspaces of maximal dimension inside sets of topological vector sequence spaces. The results we prove cover some sequence spaces not studied before in the context…

Functional Analysis · Mathematics 2015-10-06 Geraldo Botelho , Daniel Cariello , Vinícius Fávaro , Daniel Pellegrino

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

We revisit the definition of effective local compactness, and propose an approach that works for arbitrary countably-based spaces extending the previous work on computable metric spaces. We use this to show that effective local compactness…

Logic in Computer Science · Computer Science 2019-03-14 Arno Pauly

Finite topological spaces are in bijective correspondence with preorders on finite sets. We undertake their study using combinatorial tools that have been developed to investigate general discrete structures. A particular emphasis will be…

Algebraic Topology · Mathematics 2015-09-04 Loïc Foissy , Claudia Malvenuto , Frédéric Patras

Topological Ramsey spaces are spaces which support infinite dimensional Ramsey theory similarly to the Ellentuck space. Each topological Ramsey space is endowed with a partial ordering which can be modified to a $\sigma$-closed `almost…

Logic · Mathematics 2018-05-23 Natasha Dobrinen

A non-empty subset of a topological space is irreducible if whenever it is covered by the union of two closed sets, then already it is covered by one of them. Irreducible sets occur in proliferation: (1) every singleton set is irreducible,…

Logic in Computer Science · Computer Science 2016-10-04 Hadrian Andradi , Weng Kin Ho

We discuss a sufficient condition for a space to be filled with an arbitrary finite number of self-similar spaces using a topological concept.

General Topology · Mathematics 2015-07-27 Akihiko Kitada , Shousuke Ohmori , Tomoyuki Yamamoto

In this paper we consider the unbounded local completely positive and local completely contractive maps on maximal tensor product of unital locally C*-algebras and discuss on extremal points of certain convex subsets in the set of such…

Operator Algebras · Mathematics 2023-12-27 Maria Joita

An $\omega_1$-compact space is a space in which every closed discrete subspace is countable. We give various general conditions under which a locally compact, $\omega_1$-compact space is $\sigma$-countably compact, i.e., the union of…

General Topology · Mathematics 2022-06-07 Peter Nyikos , Lyubomyr Zdomskyy