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A retraction theorem for topological fundamental groups with application to the Hawaiian earring

Paul Fabel
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Abstract

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

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Paul Fabel. 2005-02-10. A retraction theorem for topological fundamental groups with application to the Hawaiian earring. https://arxiv.org/abs/math/0502218

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