English

Singular locus of rational ruled surfaces

Algebraic Geometry 2007-05-23 v2

Abstract

We prove that the morphism that maps a rational ruled surface to its singular locus is genericaly injective modulo isomophism and duality. We also calculate the dimension and the degre of its image.

Keywords

Cite

@article{arxiv.math/0101083,
  title  = {Singular locus of rational ruled surfaces},
  author = {Nicolas Perrin},
  journal= {arXiv preprint arXiv:math/0101083},
  year   = {2007}
}

Comments

In french, 25 pages. Many improvements in the proofs. New results included : the study of GIT properties of the morphism and the study of the singular locus of the image. We prove that the image is rational