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arXiv · 0906.5268

Veech groups of Loch Ness monsters

Piotr Przytycki·Gabriela Schmithuesen·Ferran Valdez
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Abstract

We classify Veech groups of tame non-compact flat surfaces. In particular we prove that all countable subgroups of $\mathbf{GL}_+(2,\R)$ avoiding the set of mappings of norm less than 1 appear as Veech groups of tame non-compact flat surfaces which are Loch Ness monsters. Conversely, a Veech group of any tame flat surface is either countable, or one of three specific types.

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Piotr Przytycki, Gabriela Schmithuesen, Ferran Valdez. 2009-06-29. Veech groups of Loch Ness monsters. https://doi.org/10.2140/agt.2017.17.529

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