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Timeline for Positive genus Fuchsian groups

Current License: CC BY-SA 4.0

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Sep 6, 2020 at 17:33 vote accept user163814
Aug 18, 2020 at 16:47 history edited Moishe Kohan CC BY-SA 4.0
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Aug 18, 2020 at 16:39 history edited Moishe Kohan CC BY-SA 4.0
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Aug 18, 2020 at 16:32 history edited Moishe Kohan CC BY-SA 4.0
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Aug 18, 2020 at 16:22 history edited Moishe Kohan CC BY-SA 4.0
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Aug 16, 2020 at 19:01 comment added Moishe Kohan @YCor: After some group-theoretic work, yes, but Siegel says nothing of sorts. It's possible that he was unaware of the result.
Aug 16, 2020 at 18:18 comment added YCor But probably the Poincaré/Siegel argument yields the whole result (not only finite generation)?
Aug 16, 2020 at 18:10 history edited Moishe Kohan CC BY-SA 4.0
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Aug 16, 2020 at 18:09 comment added Moishe Kohan @YCor: I meant discrete subgroups. As for finite generation of lattices in $PSL(2,R)$, it was known much earlier than the general case, the earliest reference I know is in Siegel's 1945 Annals paper "Some remarks on discontinuous groups." He even gives a bound on the number of generators in terms of area. Siegel's argument is by looking closely at fundamental polygons, it is likely that his proof goes back to Poincare.
Aug 16, 2020 at 17:45 comment added YCor I don't think the case of finitely generated subgroups of $(P)SL(2,\mathbf{R})$ is any easier than the general case, or even known before. However, for finitely generated discrete subgroups it's possibly an earlier result. Another issue is that it's not a trivial fact that lattices are finitely generated (it's trivial for cocompact lattices), but finite generation of arbitrary lattices is the main issue.
Aug 16, 2020 at 17:28 history answered Moishe Kohan CC BY-SA 4.0