Galois 2-extensions unramified outside 2
نویسندگان
چکیده
منابع مشابه
Unramified Abelian Extensions of Galois Covers
We consider a ramified Galois cover φ : X̂ → Px of the Riemann sphere Px, with monodromy group G. The monodromy group over Px of the maximal unramified abelian exponent n cover of X̂ is an extension nG̃ of G by the group (Z/nZ), where g is the genus of X̂. Denote the set of linear equivalence classes of divisors of degree k on X̂ by Pic(X̂) = Pic. This is equipped with a natural G action. We show tha...
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ژورنال
عنوان ژورنال: Journal of Number Theory
سال: 2007
ISSN: 0022-314X
DOI: 10.1016/j.jnt.2006.08.006