A Smooth Surface in P Not of General Type Has Degree at Most 66
نویسنده
چکیده
This is a continuation of the papers of Braun and Fløystad [BF] and Cook [C] bounding the degree of smooth surfaces not of general type in P 4. We will prove the following: Theorem 1. Let S be a smooth surface of degree d in P 4 not of general type. Then d ≤ 66. The new idea in this paper is to bound the degree of the sporadic zeros of a generic hyperplane section of the surface by considering the geometric implications of having sporadic zeros in high degree. First, we need to collect various theorems and formulae from earlier sources.
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