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The p-Rank of Ramified Covers of Curves

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Compositio Mathematica

Abstract

In this paper we study the p-rank of Abelian prime-to-p covers of the generic r-pointed curve of genus g. There is an obvious bound on the p-rank of the cover. We show that it suffices to compute the p-rank of cyclic prime-to-p covers of the generic r-pointed curve of genus zero. In that situation, we show that, for large p, the p-rank of the cover is equal to the bound.

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Bouw, I.I. The p-Rank of Ramified Covers of Curves. Compositio Mathematica 126, 295–322 (2001). https://doi.org/10.1023/A:1017513122376

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