Let M be a smooth complex projective variety and let L be a line bundle on it. Rays-positive manifolds, namely pairs (M,L) such that L is numerically effective and LR > 0 for all extremal rays R on M, are studied. Several illustrative examples and some applications are provided. In particular, projective varieties with crepant singularities and of small degree with respect to the codimension are classified, and the non-negativity of the sectional genus g(M,L) is proven, describing as well the pairs with g(M,L) = 0, 1.

Geometry of rays-positive manifolds / M.C. Beltrametti, A.L. Knutsen, A. Lanteri, C. Novelli. - In: COLLECTANEA MATHEMATICA. - ISSN 0010-0757. - 63:3(2012 Sep), pp. 375-391.

Geometry of rays-positive manifolds

A. Lanteri
Penultimo
;
2012

Abstract

Let M be a smooth complex projective variety and let L be a line bundle on it. Rays-positive manifolds, namely pairs (M,L) such that L is numerically effective and LR > 0 for all extremal rays R on M, are studied. Several illustrative examples and some applications are provided. In particular, projective varieties with crepant singularities and of small degree with respect to the codimension are classified, and the non-negativity of the sectional genus g(M,L) is proven, describing as well the pairs with g(M,L) = 0, 1.
adjunction theory; crepant singularity; Kawamata rationality theorem; pseudo-effectivity; quasi-polarized variety; rays-positive line bundle; sectional genus
Settore MAT/03 - Geometria
set-2012
Article (author)
File in questo prodotto:
File Dimensione Formato  
BKLN(rev).pdf

accesso riservato

Tipologia: Pre-print (manoscritto inviato all'editore)
Dimensione 411.29 kB
Formato Adobe PDF
411.29 kB Adobe PDF   Visualizza/Apri   Richiedi una copia
art_10.1007_s13348-011-0048-6.pdf

accesso riservato

Tipologia: Publisher's version/PDF
Dimensione 289.55 kB
Formato Adobe PDF
289.55 kB Adobe PDF   Visualizza/Apri   Richiedi una copia
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/175319
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 3
  • ???jsp.display-item.citation.isi??? 3
social impact