The 2-Ranks of Hyperelliptic Curves with Extra Automorphisms
نویسنده
چکیده
This paper examines the relationship between the automorphism group of a hyperelliptic curve defined over an algebraically closed field of characteristic two and the 2-rank of the curve. In particular, we exploit the wild ramification to use the Deuring-Shafarevich formula in order to analyze the ramification of hyperelliptic curves that admit extra automorphisms and use this data to impose restrictions on the genera and 2-ranks of such curves. We also show how some of the techniques and results carry over to the case where our base field is of characteristic p > 2.
منابع مشابه
Varieties without Extra Automorphisms Ii: Hyperelliptic Curves
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