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arXiv · 0910.2557

Un anneau de deformation universel en conducteur superieur (A universal deformation ring in higher conductor)

Gunther Cornelissen·Jakub Byszewski·Fumiharu Kato
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Abstract

Let k denote a perfect field of characteristic 5. We show that the versal deformation ring of an element of order 5 and Hasse conductor 2 as automorphism of a ring of formal power series k[[t]] computed by Bertin and Mezard, is in fact universal. This provides the first example of a non trivial universal deformation ring in higher conductor.

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Gunther Cornelissen, Jakub Byszewski, Fumiharu Kato. 2009-10-14. Un anneau de deformation universel en conducteur superieur (A universal deformation ring in higher conductor). https://arxiv.org/abs/0910.2557

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