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Related papers: Making spaces wild (simply-connected case)

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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

The paper is devoted to study the structure of Hawaiian groups of some topological spaces. We present some behaviors of Hawaiian groups with respect to product spaces, weak join spaces, cone spaces, covering spaces and locally trivial…

Algebraic Topology · Mathematics 2012-03-20 Ameneh Babaee , Behrooz Mashayekhy , Hanieh Mirebrahimi

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

We develop tools to recognize sequential spaces with large inductive dimension zero. We show the Hawaiian earring group $G$ is 0 dimensional, when endowed with the quotient topology, inherited from the space of based loops with the compact…

General Topology · Mathematics 2020-07-07 Paul Fabel

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

Endowed with quotient topology inherited from the space of based loops, the fundamental group of the Hawaiian earring fails to be metrizable. The fundamental group of any space which retracts to the Hawaiian earring is also nonmetrizable.

Geometric Topology · Mathematics 2007-05-23 Paul Fabel

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

The connected covering spaces of a connected and locally path-connected topological space $X$ can be classified by the conjugacy classes of those subgroups of $\pi_1(X,x)$ which contain an open normal subgroup of $\pi_1(X,x)$, when endowed…

Geometric Topology · Mathematics 2013-08-29 Hanspeter Fischer , Andreas Zastrow

For a path connected, locally path connected and semilocally simply connected space $X$, let $\Pi_1(X)$ denote its topologised fundamental groupoid as established in the first article of this series. Let $\mathcal{E}$ be the category of…

Algebraic Topology · Mathematics 2023-05-09 Rohit Dilip Holkar , Md Amir Hossain , Dheeraj Kulkarni

Let A be the moduli space of (1,p)-polarised abelian surfaces with a level structure, for p an odd prime. Let X be a desingularisation of any algebraic compactification of A. Then X is simply-connected.

alg-geom · Mathematics 2008-02-03 K. Hulek , G. K. Sankaran

The classical archipelago is a non-contractible subset of $\mathbb{R}^3$ which is homeomorphic to a disk except at one non-manifold point. Its fundamental group, $\mathcal{A}$, is the quotient of the topologist's product of $\mathbb Z$, the…

Algebraic Topology · Mathematics 2014-10-31 Gregory R. Conner , Wolfram Hojka , Mark Meilstrup

A characterization of regular topological fundamental groups yields a `no retraction theorem' for spaces constructed in similar fashion to the Hawaiian earring.

Algebraic Topology · Mathematics 2007-05-23 Paul Fabel

For every countable group G we construct a compact path connected subspace K of R^4 whose fundamental group is isomorphic to G. Our construction is much simpler than the one found recently by Virk.

Geometric Topology · Mathematics 2015-07-15 Adam J. Przezdziecki

In this work we present a principle which says that quasimorphisms can be obtained via "local data" of the group action on certain appropriate spaces. In a rough manner the principle says that instead of starting with a given group and try…

Group Theory · Mathematics 2012-01-31 Gabi Ben Simon

The harmonic archipelago HA is obtained by attaching a large pinched annulus to every pair of consecutive loops of the Hawaiian earring. We clarify the fundamental group pi1(HA) as a quotient of the Hawaiian earring group, provide a precise…

Algebraic Topology · Mathematics 2007-05-23 Paul Fabel

The pull back of a flat bundle $E\rightarrow X$ along the evaluation map $\pi: \mathcal{L} X \to X$ from the free loop space $\mathcal{L} X$ to $X$ comes equipped with a canonical automorphism given by the holonomies of $E$. This…

Differential Geometry · Mathematics 2015-10-19 Camilo Arias Abad , Florian Schaetz

Tree-graded spaces are a generalization of $\mathbb{R}$-trees and play an important role in describing the large-scale geometry of relatively hyperbolic groups. We consider a subclass of tree-graded spaces that we call "disjointly…

Algebraic Topology · Mathematics 2026-03-10 Jeremy Brazas , Curtis Kent

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

Suppose that X is a nonsingular variety and D is a nonsingular proper subvariety. Configuration spaces of distinct and non-distinct n points in X away from D were constructed by the author and B. Kim in arXiv:0806.3819, by using the method…

Algebraic Geometry · Mathematics 2008-08-05 Fumitoshi Sato

In this paper, we analyze the fundamental group $\pi_1(\Sigma X,\overline{x_0})$ of the reduced suspension $\Sigma X$ where $(X,x_0)$ is an arbitrary based Hausdorff space. We show that $\pi_1(\Sigma X,\overline{x_0})$ is canonically…

Algebraic Topology · Mathematics 2026-01-13 Jeremy Brazas , Patrick Gillespie
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