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On genus-change in algebraic curves over nonperfect fields

Stefan Schroeer
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Abstract

I give a new proof, in scheme-theoretic language, of Tate's old result on genus-change over nonperfect fields in characteristic p>0. Namely, for normal geometrically integral curves, the difference between arithmetic and geometric genus over the algebraic closure is divisible by (p-1)/2.

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Stefan Schroeer. 2007-03-05. On genus-change in algebraic curves over nonperfect fields. https://arxiv.org/abs/math/0703122

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