On two simple criteria for recognizing complete intersections in codimension 2
摘要
Developing a previous idea of Faltings, we characterize the complete intersections of codimension 2 in P^n, n>=3, over an algebraically closed field of any characteristic, among l.c.i. X, as those that are subcanonical and scheme-theoretically defined by p<=n-1 equations. Moreover, we give some other results assuming that the normal bundle of X extends to a numerically split bundle on P^n, p<=n and the characteristic of the base field is zero. Finally, we give a (partial) answer to a question posed recently by Franco, Kleiman and Lascu on self-linking and complete intersections in positive characteristic.
引用
@article{arxiv.math/0005142,
title = {On two simple criteria for recognizing complete intersections in codimension 2},
author = {Alessandro Arsie},
journal= {arXiv preprint arXiv:math/0005142},
year = {2007}
}
备注
10 pages, LaTeX; some hypotheses simplified; due to a misunderstanding with Lascu, I apologize for having announced a "work in progress" in the references, which, unfortunately does not exist!