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It is important to classify covering subgroups of the fundamental group of a topological space using their topological properties in the topologized fundamental group. In this paper, we introduce and study some topologies on the fundamental…

Algebraic Topology · Mathematics 2018-07-04 M. Ab dullahi Rashid , N. Jamali , B. Mashayekhy , S. Z. Pashaei , H. Torabi

Sormani and Wei proved in 2004 that a compact geodesic space has a categorical universal cover if and only if its covering/critical spectrum is finite. We add to this several equivalent conditions pertaining to the geometry and topology of…

General Topology · Mathematics 2013-09-16 Jay Wilkins

The topological fundamental group $\pi_{1}^{top}$ is a homotopy invariant finer than the usual fundamental group. It assigns to each space a quasitopological group and is discrete on spaces which admit universal covers. For an arbitrary…

Algebraic Topology · Mathematics 2020-04-14 Jeremy Brazas

The quasitopological fundamental group $\pi_{1}^{qtop}(X,x_0)$ is the fundamental group endowed with the natural quotient topology inherited from the space of based loops and is typically non-discrete when $X$ does not admit a traditional…

Algebraic Topology · Mathematics 2017-03-14 Jeremy Brazas , Paul Fabel

In this paper, we are interested in study subgroups of topologized fundamental groups and their influences on generalized covering maps. More precisely, we find some relationships between generalized covering subgroups and the other famous…

Algebraic Topology · Mathematics 2016-02-26 Mehdi Abdullahi Rashid , Behrooz Mashayekhy , Hamid Torabi , Seyyed Zeynal Pashaei

The topological fundamental group $\pi_{1}^{top}$ is a topological invariant that assigns to each space a quasi-topological group and is discrete on spaces which are well behaved locally. For a totally path-disconnected, Hausdorff, unbased…

Algebraic Topology · Mathematics 2010-07-09 Jeremy Brazas

For a connected, locally path connected space $X$, let $H$ be a subgroup of the fundamental group of $X$, $\pi_1(X,x)$. We show that there exists an open cover $\cal U$ of $X$ such that $H$ contains the Spanier group $\pi({\U},x)$ if and…

Algebraic Topology · Mathematics 2012-07-19 Hamid Torabi , Ali Pakdaman , Behrooz Mashayekhy

In this paper, using the classical covering theory, we introduce a generalization of covering maps of a space $X$ with respect to a topology $\tau$ on the fundamental group of $X$. We show that the famous notions, covering, semicovering,…

Algebraic Topology · Mathematics 2026-02-24 Naghme Shahami , Behrooz Mashayekhy

In this paper, we study some properties of homotopical closeness for paths. We define the quasi-small loop group as the subgroup of all classes of loops that are homotopically close to null-homotopic loops, denoted by $\pi_1^{qs} (X, x)$…

Algebraic Topology · Mathematics 2021-08-10 Mojtaba Moharreri , Behrooz Mashayekhy , Hanieh Mirebrahimi , Hamid Torabi , Ameneh Babaee

In this paper we devote to spaces that are not homotopically hausdorff and study their covering spaces. We introduce the notion of small covering and prove that every small covering of $X$ is the universal covering in categorical sense.…

Algebraic Topology · Mathematics 2011-03-29 Ali Pakdaman , Hamid Torabi , Behrooz Mashayekhy

In this paper, we show that every topological group is a strong small loop transfer space at the identity element. This implies that the quasitopological fundamental group of a connected locally path connected topological group is a…

Algebraic Topology · Mathematics 2018-03-05 Hamid Torabi

In this paper, by introducing some kind of small loop transfer spaces at a point, we study the behavior of topologized fundamental groups with the compact-open topology and the whisker topology, $\pi_{1}^{qtop}(X,x_{0})$ and…

This paper is devoted to the study of a natural group topology on the fundamental group which remembers local properties of spaces forgotten by covering space theory and weak homotopy type. It is known that viewing the fundamental group as…

Algebraic Topology · Mathematics 2020-04-14 Jeremy Brazas

Let $p:X\rightarrow X/A$ be a quotient map, where $A$ is a subspace of $X$. We explore conditions under which $p_*(\pi_1^{qtop}(X,x_0))$ is dense in $\pi_1^{qtop}(X/A,*))$, where the fundamental groups enjoy the natural quotient topology…

Algebraic Topology · Mathematics 2015-11-26 Hamid Torabi , Ali Pakdaman , Behrooz Mashayekhy

If $X$ is a topological group, then its fundamental groupoid $\pi_1X$ is a group-groupoid which is a group object in the category of groupoids. Further if $X$ is a path connected topological group which has a simply connected cover, then…

Category Theory · Mathematics 2016-01-27 Osman Mucuk , Tunçar Şahan

We show that the fundamental groupoid~\(\Pi_1(X)\) of a locally path connected semilocally simply connected space~\(X\) can be equipped with a \emph{natural} topology so that it becomes a topological groupoid; we also justify the necessity…

Algebraic Topology · Mathematics 2023-07-28 Rohit Dilip Holkar , Md Amir Hossain

We provide a description of the fundamental group of the quotient of a product of topological spaces $X_i$, each admitting a universal cover, by a finite group $G$, provided that there is only a finite number of path-connected components in…

Algebraic Geometry · Mathematics 2021-11-17 Rodolfo Aguilar

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

Let $(U, R)$ be an approximation space with $U$ being non-empty set and $R$ being an equivalence relation on $U$, and let $\overline{G}$ and $\underline{G}$ be the upper approximation and the lower approximation of subset $G$ of $U$. A…

General Topology · Mathematics 2020-03-03 Fucai Lin , Qianqian Sun , Yujin Lin , Jinjin Li

We study the topology of small covers from their fundamental groups. We find a way to obtain explicit presentations of the fundamental group of a small cover. Then we use these presentations to study the relations between the fundamental…

Algebraic Topology · Mathematics 2021-10-26 Lisu Wu , Li Yu
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