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Related papers: The fundamental group as a topological group

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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 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

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

This paper develops a basic theory of H-groups. We introduce a special quotient of H-groups and extend some algebraic constructions of topological groups to the category of H-groups and H-maps. We use these constructions to prove some…

Algebraic Topology · Mathematics 2010-09-28 Ali Pakdaman , Hamid Torabi , Behrooz Mashayekhy

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 order to make the fundamental group, one of the most well known invariants in algebraic topology, more useful and powerful some researchers have introduced and studied various topologies on the fundamental group from the beginning of the…

Algebraic Topology · Mathematics 2025-08-28 Naghme Shahami , Behrooz Mashayekhy

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

We exhibit a map f between aspherical spaces X and Y such that f induces an isomorphism on homotopy groups but, with natural topologies, X and Y fail to have homeomorphic fundamental groups. Thus the topological fundamental group has the…

Algebraic Topology · Mathematics 2007-05-23 Paul Fabel

A topological gyrogroup is a gyrogroup endowed with a compatible topology such that the multiplication is jointly continuous and the inverse is continuous. In this paper, we study the quotient gyrogroups in topological gyrogroups with…

General Topology · Mathematics 2022-10-10 Ying-Ying Jin , Li-Hong Xie

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 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

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

It is known that any covering space of a topological group has the natural structure of a topological group. This article discusses a noncommutative generalization of this fact. A noncommutative generalization of the topological group is a…

Operator Algebras · Mathematics 2017-05-31 Petr R. Ivankov

These lecture notes from a first course in algebraic topology use the fundamental group and orbit categories to classify covering spaces.

Algebraic Topology · Mathematics 2011-06-29 Jesper M. Møller

The natural quotient map q from the space of based loops in the Hawaiian earring onto the fundamental group provides a new example of a quotient map such that q x q fails to be a quotient map. This also settles in the negative the question…

General Topology · Mathematics 2009-12-02 Paul Fabel

We introduce and analyse a general notion of fundamental group for noncommutative spaces, described by differential graded algebras. For this we consider connections on finitely generated projective bimodules over differential graded…

Quantum Algebra · Mathematics 2019-10-23 Walter D. van Suijlekom , Jeroen Winkel

D. K. Biss (Topology and its Applications 124 (2002) 355-371) introduced the topological fundamental group and presented some interesting basic properties of the notion. In this article we intend to extend the above notion to homotopy…

Algebraic Topology · Mathematics 2011-02-02 Helen Ghane , Zainab Hamed , Behrooz Mashayekhy , Hanieh Mirebrahimi

We offer a counterexample to a theorem in the literature and then repair the theorem as follows: The fundamental group of a locally path connected metric space inherits the discrete topology in a natural way if and only if the underlying…

General Topology · Mathematics 2007-05-23 Paul Fabel

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

In algebraic topology, the fundamental groupoid is a classical homotopy invariant which is defined using continuous maps from the closed interval to a topological space. In this paper, we construct a semi-coarse version of this invariant,…

Algebraic Topology · Mathematics 2025-03-06 Jonathan Treviño-Marroquín
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