Hopfian Groups are Complete co-Analytic

Brian Pinsky

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arXiv · 2303.00839

Hopfian Groups are Complete co-Analytic

Brian Pinsky

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Abstract

We show the set of Hopfian countable groups is a complete co-analytic subset of the standard Borel space of countable groups, resolving a question posed by Simon Thomas (https://doi.org/10.1007/s00153-017-0597-9).

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Brian Pinsky. 2023-03-01. Hopfian Groups are Complete co-Analytic. https://arxiv.org/abs/2303.00839

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