English

Generalized polarized manifolds with low second class

Algebraic Geometry 2018-11-06 v2

Abstract

On a smooth complex projective variety XX of dimension nn, consider an ample vector bundle E\mathcal{E} of rank rn2r \leq n-2 and an ample line bundle HH. A numerical character m2=m2(X,E,H)m_2=m_2(X,\mathcal{E},H) of the triplet (X,E,H)(X,\mathcal{E},H) is defined, extending the well-known second class of a polarized manifold (X,H)(X,H), when either n=2n=2 or HH is very ample. Under some additional assumptions on F:=EH(nr2)\mathcal{F}: = \mathcal{E} \oplus H^{\oplus (n-r-2)}, triplets (X,E,H)(X,\mathcal{E},H) as above whose m2m_2 is small with respect to the invariants d:=cn2(F)H2d:=c_{n-2}(\mathcal{F})H^2 and g:=1+12(KX+c1(F)+H)cn2(F)Hg:=1+\frac{1}{2}\big(K_X + c_1(\mathcal{F})+H\big) \cdot c_{n-2}(\mathcal{F}) \cdot H are studied and classified.

Keywords

Cite

@article{arxiv.1608.07732,
  title  = {Generalized polarized manifolds with low second class},
  author = {Antonio Lanteri and Andrea Luigi Tironi},
  journal= {arXiv preprint arXiv:1608.07732},
  year   = {2018}
}

Comments

23 pages; the final presentation of the main topics has been improved with some changes, especially in Table 1, and some typos have been corrected

R2 v1 2026-06-22T15:32:50.915Z