arXiv math/00081692000-08math.AG

On kth-order embeddings of K3 surfaces and Enriques surfaces

Andreas Leopold Knutsen

备注：: 23 pages, 0 figures, slightly improved version (Section 4), added references, to appear in Manuscr. Math

英文摘要：

We give necessary and sufficient conditions for a big and nef line bundle L of any degree on a K3 surface or Enriques surface to be k-very ample and k-spanned. Furthermore, we give necessary and sufficient conditions for a spanned and big line bundle on a K3 surface to be birationally k-very ample and birationally k-spanned, and relate these concepts to the Clifford index and gonality of smooth curves in |L|.

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