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arXiv · 1303.2954

On the deformation of a Barsotti-Tate group over a curve

Jie Xia
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Abstract

In this paper, we study deformations of pairs (C,G) where G is a height 2 BT(or BT_n) group over a complete curve on algebraically closed field k of characteristic p. We prove that, if the curve C is a versal deformation of G, then there exists a unique lifting of the pair to the Witt ring W. We apply this result in the case of Shimura curves to obtain a lifting criterion.

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Jie Xia. 2013-03-12. On the deformation of a Barsotti-Tate group over a curve. https://arxiv.org/abs/1303.2954

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