Points in projective spaces and applications

Abstract

We prove the factoriality of a nodal hypersurface in ${\mathbb{P}}^4$ of degree $d$ that has at most $2(d-1{)}^2/3$ singular points, and factoriality of a double cover of ${\mathbb{P}}^3$ branched over a nodal surface of degree $2r$ having less than $(2r-1)r$ singular points.

16 pages

Cited by in corpus (1)

• On rational maps from a general surface in P^3 to surfaces of general type