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arXiv · 1302.3813

Affine surfaces with a huge group of automorphisms

Jérémy Blanc·Adrien Dubouloz
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Abstract

We describe a family of rational affine surfaces S with huge groups of automorphisms in the following sense: the normal subgroup of Aut(S) generated by all its algebraic subgroups is not generated by any countable family of such subgroups, and the quotient of Aut(S) by this subgroup contains a free group over an uncountable set of generators.

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Jérémy Blanc, Adrien Dubouloz. 2013-02-15. Affine surfaces with a huge group of automorphisms. https://arxiv.org/abs/1302.3813

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