Projectively normal adjunction surfaces
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- by Marco Andreatta and Edoardo Ballico PDF
- Proc. Amer. Math. Soc. 112 (1991), 919-924 Request permission
Abstract:
On a projective surface $S$ polarized by a very ample line bundle $L$ one can consider the adjoint bundles ${({K_S} \otimes L)^{ \otimes n}} = {L^{ \otimes n}}$ and the adjunction mappings associated to them. Suppose these mappings are embeddings (it is well known when this is the case: see [So-VdV]). We prove that these embeddings are projectively normal for $n \geq 2$ and we describe some counterexamples for $n = 1$. For $n \geq 2$ we show that the ideals of the image of $S$ are generated by quadrics.References
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Additional Information
- © Copyright 1991 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 112 (1991), 919-924
- MSC: Primary 14J25
- DOI: https://doi.org/10.1090/S0002-9939-1991-1057947-X
- MathSciNet review: 1057947