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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

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

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

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

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

We show that for every subset X of a closed surface M^2 and every basepoint x_0, the natural homomorphism from the fundamental group to the first shape homotopy group, is injective. In particular, if X is a proper compact subset of M^2,…

Group Theory · Mathematics 2014-10-01 Hanspeter Fischer , Andreas Zastrow

This paper is devoted to study some topological properties of the SG subgroup, $\pi_1^{sg}(X,x)$, of the quasitopological fundamental group of a based space $(X,x)$, $\pt$, its topological properties as a subgroup of the topological…

Algebraic Topology · Mathematics 2016-01-15 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

Let $H$ be a subgroup of $\pi_{1}(X,x_{0})$. In this paper, we extend the concept of $X$ being SLT space to $H$-SLT space at $x_0$. First, we show that the fibers of the endpoint projection $p_{H}:\tilde{X}_{H}\rightarrow X$ are topological…

Algebraic Topology · Mathematics 2017-04-27 S. Z. Pashaei , B. Mashayekhy , H. Torabi , M. Abdullahi Rashid

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 topology on the set of shape morphisms between arbitrary topological spaces $X$, $Y$, $Sh(X,Y)$, defined by Cuchillo-Ibanez et al. in 1999, we consider a topology on the shape homotopy groups of arbitrary…

Algebraic Topology · Mathematics 2015-11-26 Tayyebe Nasri , Fatemeh Ghanei , Behrooz Mashayekhy , Hanieh Mirebrahimi

The path component space of a topological space $X$ is the quotient space $\pi_0(X)$ whose points are the path components of $X$. We show that every Tychonoff space $X$ is the path-component space of a Tychonoff space $Y$ of weight…

General Topology · Mathematics 2020-04-14 Taras Banakh , Jeremy Brazas

Let $X$ be a locally 1-connected metric space and $A_1,A_2,...,A_n$ be connected, locally path connected and compact pairwise disjoint subspaces of $X$. In this paper, we show that the quotient space $X/(A_1,A_2,...,A_n)$ obtained from $X$…

Algebraic Topology · Mathematics 2015-07-29 Ali Pakdaman , Hamid Torabi , Behrooz Mashayekhy

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…

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

Uchillo-Ibanez et al. introduced a topology on the sets of shape morphisms between arbitrary topological spaces in 1999. In this paper, applying a similar idea, we introduce a topology on the set of coarse shape morphisms $Sh^*(X,Y)$, for…

Algebraic Topology · Mathematics 2016-04-05 Fateme Ghanei , Hanieh Mirebrahimi , Behrooz Mashayekhy , Tayyebe Nasri

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 construct a space $\mathbb{P}$ for which the canonical homomorphism $\pi_1(\mathbb{P},p) \rightarrow \check{\pi}_1(\mathbb{P},p)$ from the fundamental group to the first \v{C}ech homotopy group is not injective, although it has all of…

Algebraic Topology · Mathematics 2020-12-07 Jeremy Brazas , Hanspeter Fischer

For a path-connected metric space $(X,d)$, the $n$-th homotopy group $\pi_n(X)$ inherits a natural pseudometric from the $n$-th iterated loop space with the uniform metric. This pseudometric gives $\pi_n(X)$ the structure of a topological…

Algebraic Topology · Mathematics 2025-01-27 Jeremy Brazas , Paul Fabel

Let $X$ be a path connected, locally path connected and semilocally simply connected space; let $\tilde{X}$ be its universal cover. We discuss the existence and description of a Haar system on the fundamental groupoid $\Pi_1(X)$ of $X$. The…

Operator Algebras · Mathematics 2023-05-12 Rohit Dilip Holkar , Md Amir Hossain
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