English

Threefolds of P^5 with one apparent quadruple point

Algebraic Geometry 2017-02-03 v1

Abstract

In this article we classify all the smooth threefolds of P^5 with an apparent quadruple point provided that the family of its 4-secant lines is an irreducible (first order) congruence. This is sufficient to conclude the classification of all the smooth codimension two varieties of P^n with one apparent (n-1)-point and with irreducible family of (n-1)-secant lines.

Keywords

Cite

@article{arxiv.math/0207104,
  title  = {Threefolds of P^5 with one apparent quadruple point},
  author = {Pietro De Poi},
  journal= {arXiv preprint arXiv:math/0207104},
  year   = {2017}
}

Comments

AMS-LaTeX2e, 14 pages