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arXiv · 1005.2142

Deformations of elliptic fibre bundles in positive characteristic

Holger Partsch
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Abstract

We study deformation theory of elliptic fibre bundles over curves in positive characteristics. As applications, we give examples of non-liftable elliptic surfaces in charactertic two and three, which answers a question of Katsura and Ueno. Also, we construct a class of elliptic fibrations, whose liftability is equivalent to a conjecture of F. Oort concerning the liftability of automorphisms of curves. Finally, we classify deformations of bielliptic surfaces.

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Holger Partsch. 2010-05-12. Deformations of elliptic fibre bundles in positive characteristic. https://doi.org/10.1215/00277630-2141608

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