Induction and restriction in formal deformation of coverings

Jose Bertin; Ariane Mezard

Induction and restriction in formal deformation of coverings

Algebraic Geometry 2016-09-07 v1

Authors: Jose Bertin , Ariane Mezard

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).

Keywords

semistable curves group actions formal deformation equivariant functors induction restriction

Cite

@article{arxiv.math/0205228,
  title  = {Induction and restriction in formal deformation of coverings},
  author = {Jose Bertin and Ariane Mezard},
  journal= {arXiv preprint arXiv:math/0205228},
  year   = {2016}
}