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Proceedings of the American Mathematical Society
Proceedings of the American Mathematical Society
ISSN 1088-6826(e) ISSN 0002-9939(p)

     

Multisecant subspaces to smooth projective varieties in arbitrary characteristic

Author(s): Atsushi Noma
Journal: Proc. Amer. Math. Soc. 137 (2009), 3985-3990.
MSC (2000): Primary 14N05, 14H45
Posted: July 1, 2009
MathSciNet review: 2538558
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Abstract | References | Similar articles | Additional information

Abstract: Let $ X \subseteq \mathbb{P}^{N}$ be a projective variety of dimension $ n\geq 1$, degree $ d$, and codimension $ e$, not contained in any hyperplane, defined over an algebraically closed field $ \Bbbk$ of arbitrary characteristic. We show that if a $ k$-dimensional linear subspace $ M$ meets $ X$ at the smooth locus such that $ X\cap M$ is finite and locally lies on a smooth curve, then the length $ l(X\cap M)$ does not exceed $ d-e+k-\min \{g,e-k\}$ for the sectional genus $ g$ of $ X$.


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Additional Information:

Atsushi Noma
Affiliation: Department of Mathematics, Faculty of Education and Human Sciences, Yokohama National University, Yokohama 240-8501, Japan
Email: noma@edhs.ynu.ac.jp

DOI: 10.1090/S0002-9939-09-09977-8
PII: S 0002-9939(09)09977-8
Keywords: Secant line, secant space, sectional genus
Received by editor(s): June 1, 2007,
Received by editor(s) in revised form: March 20, 2009
Posted: July 1, 2009
Additional Notes: This work was partially supported by the Japan Society for the Promotion of Science.
Communicated by: Ted Chinburg
Copyright of article: Copyright 2009, American Mathematical Society
The copyright for this article reverts to public domain after 28 years from publication.




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