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SUPERFICIAL FIBRES OF GENERIC PROJECTIONS

Part of: Projective and enumerative geometry

Published online by Cambridge University Press:  08 March 2016

Ziv Ran
Ziv Ran*
Affiliation:
Mathematics Department, University of California, Surge Facility, Big Springs Road, Riverside, CA 92521, USA (ziv.ran@ucr.edu)
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Abstract

We consider a general fibre of given length in a generic projection of a variety. Under the assumption that the fibre is of local embedding dimension 2 or less, an assumption which can be checked in many cases, we prove that the fibre is reduced and its image on the projected variety is an ordinary multiple point.

Keywords

multisecant planesgeneric projectionsmultiple pointspunctual schemes

MSC classification

Primary: 14N05: Projective techniques
Type
Research Article
Information
Journal of the Institute of Mathematics of Jussieu , Volume 17 , Issue 2 , April 2018 , pp. 419 - 424
Copyright
© Cambridge University Press 2016 

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