Induction and restriction in formal deformation of coverings

Jose Bertin; Ariane Mezard

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Induction and restriction in formal deformation of coverings

Jose Bertin·Ariane Mezard

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Abstract

Let X/S be a semistable curve with an action of a finite group G and let H be a normal subgroup of G. We present a new condition under which for any base change T->S, (X/G)*T is isomorphic to (X*T)/G. This allows us to define induction and restriction morphisms between the G-equivariant deformation functor of X and the G/H-equivariant (resp. H-equivariant) deformation functor of X/H (resp. X).

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Jose Bertin, Ariane Mezard. 2002-05-22. Induction and restriction in formal deformation of coverings. https://arxiv.org/abs/math/0205228

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