6 papers · 1 filter
Low dimensional discriminant loci and scrolls
Antonio Lanteri, Roberto Munoz
Smooth complex polarized varieties with a vector subspace spanning are classified under the assumption that the locus ${\Cal D}(X,V)$ of singular…
Ample subvarieties and rationally connected fibrations
Mauro C. Beltrametti, Tommaso de Fernex, Antonio Lanteri
Under some positivity assumptions, extension properties of rationally connected fibrations from a submanifold to its ambient variety are studied. Given a family of rational curves…
Higher Order Bad Loci
Gian Mario Besana, Sandra Di Rocco, Antonio Lanteri
Zero-schemes on smooth complex projective varieties, forcing all elements of ample and free linear systems to be reducible are studied. Relationships among the minimal length of su…
Inflectional loci of scrolls
Antonio Lanteri, Raquel Mallavibarrena, Ragni Piene
Let be a scroll over a smooth curve and let denote the hyperplane bundle. The special geometry of implies that som…
Bad loci of free linear systems
Tommaso de Fernex, Antonio Lanteri
The bad locus of a base-point free linear system L on a normal complex projective variety X is defined as the subset B(L) of X of points that are not contained in any irreducible a…
Peculiar Loci of Ample and Spanned Line Bundles
Gian Mario Besana, Sandra Di Rocco, Antonio Lanteri
The bad locus and the rude locus of an ample and base point free linear system on a smooth complex projective variety are introduced and studied. The bad locus is defined as the se…