Déformations équivariantes des courbes semistables  [ Equivariant deformations of semi-stable curves ]
Annales de l'Institut Fourier, Volume 55 (2005) no. 6, p. 1905-1941

In this paper we study deformation theory of wildly ramified Galois coverings between stables curves. We first study the local aspects concerning a formal double point with a p-group as inertia group, and then the global case. We compare global obstructions and local obstructions to the lifting problem.

Nous étudions la théorie des déformations des revêtements galoisiens sauvagement ramifiés entre courbes stables. On examine d’abord les problèmes locaux, point double formel avec pour groupe d’inertie un p-groupe, puis le cas global. On compare enfin les obstructions globales au relèvement aux obstructions locales.

DOI : https://doi.org/10.5802/aif.2146
Classification:  14H10,  14H30,  14B10
Keywords: covering, deformation, double point 
@article{AIF_2005__55_6_1905_0,
     author = {Bertin, Jos\'e and Maugeais, Sylvain},
     title = {D\'eformations \'equivariantes des courbes semistables},
     journal = {Annales de l'Institut Fourier},
     publisher = {Association des Annales de l'institut Fourier},
     volume = {55},
     number = {6},
     year = {2005},
     pages = {1905-1941},
     doi = {10.5802/aif.2146},
     zbl = {1095.14022},
     mrnumber = {2187940},
     language = {fr},
     url = {http://www.numdam.org/item/AIF_2005__55_6_1905_0}
}

Bertin, José; Maugeais, Sylvain. Déformations équivariantes des courbes semistables. Annales de l'Institut Fourier, Volume 55 (2005) no. 6, pp. 1905-1941. doi : 10.5802/aif.2146. http://www.numdam.org/item/AIF_2005__55_6_1905_0/

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