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arXiv · 1904.07689

Free groups, covering spaces and Artin's theorem

Gopala Krishna Srinivasan
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Abstract

In this expository note we provide a proof of Artin's theorem which states that the commutator subgroup of a free group on two generators is not finitely generated. The proof employs the infinite grid as in two other proofs in the literature mentioned in the note but takes a somewhat different approach which seems to be of didactic value.

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Gopala Krishna Srinivasan. 2019-04-13. Free groups, covering spaces and Artin's theorem. https://arxiv.org/abs/1904.07689

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