0 Fe b 20 09 FINITE MORPHISMS FROM CURVES OVER DEDEKIND RINGS TO
نویسنده
چکیده
A theorem of B. Green states that if A is a Dedekind ring whose fraction field is a local or global field, every normal projective curve over Spec(A) has a finite morphism to P1A. We give a different proof of a variant of this result using intersection theory and work of Moret-Bailly.
منابع مشابه
0 90 2 . 12 36 v 2 [ m at h . A C ] 1 3 Fe b 20 09 Rings over which every projective ideal is free
In this paper we introduce and investigate a class of those rings in which every projective ideal is free. We establish the transfer of this notion to the trivial ring extension and pullbacks and then generate new and original families of rings satisfying this property.
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