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arXiv · 0804.3494

Large p-groups actions with |G| /g^2 > 4/ (p^2-1)^2

Magali Rocher
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Abstract

Let k be an algebraically closed field of characteristic p>0 and C a connected nonsingular projective curve over k with genus g>1. Let (C,G) be a "big action", i.e. a pair (C,G) where G is a p-subgroup of the k-automorphism group of C such that |G|/g > 2p / p-1. We first study finiteness results on the values taken by the quotient |G|/g^2 when (C,G) runs over the big actions satisfying |G|/g^2 >M, for a given positive real M>0. Then, we exhibit a classification and a parametrization of such big actions when M=4/ (p^2-1)^2.

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Magali Rocher. 2008-04-22. Large p-groups actions with |G| /g^2 > 4/ (p^2-1)^2. https://arxiv.org/abs/0804.3494

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