Unramified Covers of Galois Covers of Low Genus Curves
نویسنده
چکیده
Let X → Y be a Galois covering of curves, where the genus of X is ≥ 2 and the genus of Y is ≤ 2. We prove that under certain hypotheses, X has an unramified cover that dominates a hyperelliptic curve; our results apply, for instance, to all tamely superelliptic curves. Combining this with a theorem of Bogomolov and Tschinkel shows that X has an unramified cover that dominates y = x − 1, if char k is not 2 or 3.
منابع مشابه
Covers of the affine line in positive characteristic with prescribed ramification
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