Boundedness for Threefolds in P Containing a Smooth Ruled Surface as Hyperplane Section
نویسنده
چکیده
Let X ⊂ P be a smooth irreducible projective threefold, and d its degree. In this paper we prove that there exists a constant β such that for all X containing a smooth ruled surface as hyperplane section and not contained in a fourfold of degree less than or equal to 15, d ≤ β. Under some more restrictive hypothesis we prove an analogous result for threefolds containing a smooth ruled surface as hyperplane section and contained in a fourfold of degree less than or equal to 15.
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تاریخ انتشار 2014