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arXiv · 1908.06675

A short proof of Greenberg's Theorem

Gareth A. Jones
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Abstract

Greenberg proved that every countable group $A$ is isomorphic to the automorphism group of a Riemann surface, which can be taken to be compact if $A$ is finite. We give a short and explicit algebraic proof of this for finitely generated groups $A$.

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Gareth A. Jones. 2019-08-19. A short proof of Greenberg's Theorem. https://arxiv.org/abs/1908.06675

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