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Pseudo-contractibility of chainable continua - MaRDI portal

Pseudo-contractibility of chainable continua (Q2384409)

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Pseudo-contractibility of chainable continua
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    Pseudo-contractibility of chainable continua (English)
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    21 September 2007
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    A space \(X\) is called \textit{pseudo-contractible} if there exist a continuum \(C\), points \(a, b \in C\) and a map \(H: X \times C \to X\) such that \(H(\cdot, a)\) is the identity and \(H(\cdot, b)\) is a constant map. A continuum is \textit{chainable} if it admits an \(\varepsilon\)-map onto the unit interval for every \(\varepsilon > 0\). In the paper under review, the author shows that the only pseudo-contractible chainable continuum is the arc. This answers a question of \textit{W. Kuperberg} [Problem 31, in \textit{H. Cook, W. T. Ingram} and \textit{A. Lelek}, ``A list of problems known as Houston problem book'', Lect. Notes Pure Appl. Math. 170, 365--398 (1995; Zbl 0828.54001)].
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    pseudo-contractibility
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    chainable
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