Arrondo Esteban, Enrique and Bertolini, Marina and Turrini, Cristina
(2005)
*Focal loci in G(1,N).*
Asian journal of mathematics, 9
(4).
pp. 449-472.
ISSN 1093-6106

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## Abstract

We introduce the different focal loci (focal points, planes and hyperplanes) of (n - 1)-dimensional families (congruences) of lines in P-n and study their invariants, geometry and the relation among them. We also study some particular congruences whose focal loci have special behaviour, namely (n - 1)-secant lines to an (n - 2)-fold and (n - 1)-tangent lines to a hypersurface. In case n = 4 we also give, under some smoothness assumptions, a classification result for these congruences.

Item Type: | Article |
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Uncontrolled Keywords: | Focal locus; congruence; Grassmannian of lines |

Subjects: | Sciences > Mathematics > Algebraic geometry |

ID Code: | 14822 |

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Deposited On: | 18 Apr 2012 09:33 |

Last Modified: | 06 Feb 2014 10:10 |

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