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arXiv · 1104.2222

Sekiguchi-Suwa theory revisited

Ariane Mézard·Matthieu Romagny·Dajano Tossici
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Abstract

We present an account of the construction by S. Sekiguchi and N. Suwa of a cyclic isogeny of affine smooth group schemes unifying the Kummer and Artin-Schreier-Witt isogenies. We complete the construction over an arbitrary base ring. We extend the statements of some results in a form adapted to a further investigation of the models of the group schemes of roots of unity.

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Ariane Mézard, Matthieu Romagny, Dajano Tossici. 2011-04-12. Sekiguchi-Suwa theory revisited. https://arxiv.org/abs/1104.2222

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