Constructing Reducible Brill-Noether Curves II
نویسنده
چکیده
In this paper, we study maps from reducible curves f : C∪ΓD → Pr, where f |D factors through a hyperplane H, and f |C is transverse to H. Degeneration to stable maps of this type have played a crucial role in works of Hartshorne, Ballico, and others, on special cases of the maximal rank conjecture. However, the general problem of studying when such stable maps with specified combinatorial types exist remains open. Here, we give criteria for such Brill-Noether curves to exist, of specified degree d and genus g, such that f |C is of specified degree d′ and genus g′. These results will play a key role in the proof of the maximal rank conjecture in a forthcoming paper.
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