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

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In this paper it is shown how to construct a finite topological space $X$ for a given finitely presentable group $G$ such that $\pi_1(X)\cong G$. Our construction is not optimal in the sense that the cardinality of the space $X$ might not…

Algebraic Topology · Mathematics 2021-01-01 Samuel Roldán , Jose Luis Mora , Edward Becerra

Our main problem is to find finite topological spaces to within homeomorphism, given (also to within homeomorphism) the quotient-spaces obtained by identifying one point of the space with each one of the other points. In a previous version…

General Topology · Mathematics 2018-06-25 J. M. S. Simoes-Pereira

In this paper we study the bicomplex version of weighted Hardy spaces. Further, we describe reproducing kernels for the bicomplex weighted Hardy spaces. In particular, we generalize some results which holds for the classical weighted Hardy…

Functional Analysis · Mathematics 2015-03-03 Romesh Kumar , Kulbir Singh , Heera Saini , Sanjay Kumar

An ideal is a nonempty collection of subsets closed under heredity and finite additivity. The aim of this paper is to unify some weak separation properties via topological ideals. We concentrate our attention on the separation axioms…

General Topology · Mathematics 2007-05-23 Francisco G. Arenas , Julian Dontchev , Maria Luz Puertas

For each $n \in \mathbb{N}$ a Banach space $\mathfrak{X}_{0,1}^n$ is constructed is having the property that every normalized weakly null sequence generates either a $c_0$ or $\ell_1$ spreading models and every infinite dimensional subspace…

Functional Analysis · Mathematics 2013-09-19 Spiros Argyros , Kevin Beanland , Pavlos Motakis

We present examples of realcompact spaces with closed subsets that are C*-embedded but not C-embedded, including one where the closed set is a copy of the space of natural numbers.

General Topology · Mathematics 2023-08-28 Alan Dow , Jan van Mill , Klaas Pieter Hart , Hans Vermeer

In this paper, we study the descriptive complexity of some inevitable classes of Banach spaces. Precisely, as shown in [Go], every Banach space either contains a hereditarily indecomposable subspace or an unconditional basis, and, as shown…

Functional Analysis · Mathematics 2016-12-23 Bruno de Mendonça Braga

In this paper, some features of countably $\alpha$-compact topological spaces are presented and proven. The connection between countably $\alpha$% -compact, Tychonoff, and $\alpha$-Hausdorff spaces is explained. The space is countably…

General Topology · Mathematics 2022-05-25 Eman Almuhur , Muhammad Ahsan Khan

We classify fields having finitely many finite non-commutative (not necessarily central) division algebras over them. In the process, we introduce the notion of anti-closure of a field and also make comments on fields having a linear…

Rings and Algebras · Mathematics 2023-09-18 Snehinh Sen

In \cite{Chaber}, Chaber has proved that countably compact spaces with a quasi $G_{\delta }$-diagonal are compact. We prove that initially $\kappa $% -compact spaces with a quasi $G_{\kappa }$-diagonal are compact, for any infinite cardinal…

General Topology · Mathematics 2017-05-02 Çetin Vural

We define several topological spaces whose points are quivers with a given infinite vertex set $X$. In the special case when $X$ is countably infinite, we show that two of the spaces of interest are homeomorphic to the Baire space…

Combinatorics · Mathematics 2026-04-21 Benjamin Grant

Working over the field of order 2 we consider those complete caps (maximal sets of points with no three collinear) which are disjoint from some codimension 2 subspace of projective space. We derive restrictive conditions which such a cap…

Combinatorics · Mathematics 2007-05-23 David L. Wehlau

In this paper, we give a topological version of Scott convergence theorem for locally hypercompact spaces. We introduce the notion of $\mathcal{S}^*_X$-convergence on a $T_0$ topological space $X$, and define the notion of finitely…

General Topology · Mathematics 2023-08-09 Yuxu Chen , Hui Kou

We study the space of traces associated with arbitrary full free products of unital, separable $C^*$-algebras. We show that, unless certain basic obstructions (which we fully characterize) occur, the space of traces always results in the…

Operator Algebras · Mathematics 2024-12-19 Adrian Ioana , Pieter Spaas , Itamar Vigdorovich

This paper deals with the existence, or absence, of coalescent contractions of contractible spaces. These are the contractions such that when the tracks of any two points meet, at time t0, they remain together thereafter. If a finite…

Geometric Topology · Mathematics 2021-09-21 Eduardo Francisco Rêgo

We define a universal Teichm\"uller space for locally quasiconformal mappings whose dilatation grows not faster than a certain rate. Paralleling the classical Teichm\"uller theory, we prove results of existence and uniqueness for extremal…

Complex Variables · Mathematics 2019-07-19 Alastair Fletcher , Zhou Zemin

Uniformly finite homology is a coarse invariant for metric spaces; in particular, it is a quasi-isometry invariant for finitely generated groups. In this article, we study uniformly finite homology of finitely generated amenable groups and…

Group Theory · Mathematics 2016-01-20 Matthias Blank , Francesca Diana

We discuss the problem of finding an analogue of the concept of a topological space in supergeometry, motivated by a search for a procedure to compactify a supermanifold along odd coordinates. In particular, we examine the topologies…

General Topology · Mathematics 2007-05-23 Ugo Bruzzo , Vladimir Pestov

A characterization of finite homogeneous ultrametric spaces and finite ultrametric spaces generated by unrooted labeled trees is found in terms of representing trees. A characterization of finite ultrametric spaces having perfect strictly…

General Topology · Mathematics 2024-12-24 Evgeniy A. Petrov

A positive space is a space with a positive atlas, i.e. a collection of rational coordinate systems with subtraction free transition functions. The set of positive real points of a positive space is well defined. We define a tropical…

Algebraic Geometry · Mathematics 2015-10-27 V. V. Fock , A. B. Goncharov