English
Related papers

Related papers: On quasi-small loop groups

200 papers

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

We verify that for a finite simplicial complex $X$ and for piecewise linear loops on $X$, the "thin" loop space is a topological group of the same homotopy type as the space of continuous loops. This turns out not to be the case for the…

Algebraic Topology · Mathematics 2019-09-26 Moncef Ghazel , Sadok Kallel

A class of almost paratopological groups is introduced, which (1) contains paratopological groups and Hausdorff quasitopological groups; (2) is closed under products; (3) subgroups. Almost paratopological $T_1$ groups $G$ are characterized…

General Topology · Mathematics 2023-08-22 Evgenii Reznichenko

Let X be a zero-dimensional compact space such that all non-empty clopen subsets of X are homeomorphic to each other, and let H(X) be the group of all self-homeomorphisms of X with the compact-open topology. We prove that the Roelcke…

General Topology · Mathematics 2021-08-27 V. V. Uspenskij

The paper is devoted to study the behavior of quasitopological homotopy groups on inverse limit spaces. More precisely, we present some conditions under which the quasitopological homotopy group of an inverse limit space and especially a…

Algebraic Topology · Mathematics 2015-07-29 Tayyabe Nasri , Behrooz Mashayekhy , Hanieh Mirebrahimi

A quasi-tree is a geodesic metric space quasi-isometric to a tree. We give a general construction of many actions of groups on quasi-trees. The groups we can handle include non-elementary (relatively) hyperbolic groups, rank 1 CAT(0)…

Group Theory · Mathematics 2014-09-09 Mladen Bestvina , Kenneth Bromberg , Koji Fujiwara

In this paper, we study a special class of quasi-homomorphisms, i.e. quasi-retractions from a group to its subgroups. We first give some algebraic and geometric properties of quasi-retracts and then propose a theory of quasi-split short…

Group Theory · Mathematics 2025-08-21 Renxing Wan

The quasi-redirecting (QR) boundary is a close generalization of the Gromov boundary to all finitely generated groups. In this paper, we establish that the QR boundary exists as a topological space for several well-studied classes of…

Group Theory · Mathematics 2025-04-01 Hoang Thanh Nguyen , Yulan Qing

In this study we introduce the notions of semi-homotopy of semi-continuous maps and of semi-paths. We also construct a group structure, which will be called semi-fundamental group, using semi-loops and explore some properties of…

Algebraic Topology · Mathematics 2016-04-27 Ayhan Erciyes , Ali Aytekin , Tunçar Şahan

Let $H$ be a subgroup of the fundamental group $\pi_{1}(X,x_{0})$. By extending the concept of strong SLT space to a relative version with respect to $H$, strong $H$-SLT space, first, we investigate the existence of a covering map for…

Algebraic Topology · Mathematics 2017-11-07 S. Z. Pashaei , B. Mashayekhy , M. Abdullahi Rashid

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

In this paper we define a family of theories, quasi-theories, motivated by quasi-elliptic cohomology. They can be defined from constant loop spaces. With them, the constructions on certain theories can be made in a neat way, such as those…

Algebraic Topology · Mathematics 2018-09-19 Zhen Huan

The paper deals with quasigroups having a trivial group of automorphisms and a trivial group of autotopisms. Examples of such quasigroups and methods of their verification are given.

Group Theory · Mathematics 2009-05-26 Andriy I. Deriyenko , Ivan I. Deriyenko , Wieslaw A. Dudek

We describe structure of quasihomomorphisms from arbitrary groups to discrete groups. We show that all quasihomomorphisms are 'constructible', i.e., are obtained via certain natural operations from homomorphisms to some groups and…

Group Theory · Mathematics 2015-07-09 Koji Fujiwara , Michael Kapovich

By a quasi-connected reductive group (a term of Labesse) over an arbitrary field we mean an almost direct product of a connected semisimple group and a quasi-torus (a smooth group of multiplicative type). We show that a linear algebraic…

Representation Theory · Mathematics 2021-09-21 Mikhail Borovoi , Andrei A. Gornitskii , Zev Rosengarten

We study the homotopy type of spaces of commuting elements in connected nilpotent Lie groups, via almost commuting elements in their Lie algebras. We give a necessary and sufficient condition on the fundamental group of such a Lie group $G$…

Algebraic Topology · Mathematics 2026-02-25 Omar Antolín-Camarena , Bernardo Villarreal

By generalizing the whisker topology on the $n$th homotopy group of pointed space $(X, x_0)$, denoted by $\pi_n^{wh}(X, x_0)$, we show that $\pi_n^{wh}(X, x_0)$ is a topological group if $n \ge 2$. Also, we present some necessary and…

The article is devoted to a structure of topological spaces related with topological quasigroups. Regular and complete spaces over topological quasigroups are studied. Separations and embeddings are also investigated for them. Their…

Group Theory · Mathematics 2023-12-29 S. V. Ludkowski

This (quasi-)survey addresses the quasi-isometry classification of locally compact groups, with an emphasis on amenable hyperbolic locally compact groups. This encompasses the problem of quasi-isometry classification of homogeneous…

Group Theory · Mathematics 2020-05-05 Yves Cornulier

This paper aims to introduce a more general definition of quasirandom groups and generalize several well-known results in the literature in this new setting. More precisely, let $G$ be a semi-direct product of groups and $X\subseteq G$, we…

Combinatorics · Mathematics 2023-08-28 Thang Pham , Boqing Xue