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Related papers: A classification theorem on Fano bundles

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Generalising a classical theorem by Ueno, we prove structure results for manifolds with nef or semiample cotangent bundle.

Algebraic Geometry · Mathematics 2017-11-07 Andreas Höring

We address the problem of classification of contact Fano manifolds. It is conjectured that every such manifold is necessarily homogeneous. We prove that the Killing form, the Lie algebra grading and parts of the Lie bracket can be read from…

Algebraic Geometry · Mathematics 2021-02-16 Jarosław Buczyński

We present a reconstruction theorem for Fano vector bundles on projective space which recovers the small quantum cohomology for the projectivisation of the bundle from a small number of low-degree Gromov--Witten invariants. We provide an…

Algebraic Geometry · Mathematics 2013-02-25 Andrew Strangeway

We determine the stability/instability of the tangent bundles of the Fano varieties in a certain class of two orbit varieties, which are classified by Pasquier in 2009. As a consequence, we show that some of these varieties admit unstable…

Algebraic Geometry · Mathematics 2020-01-01 Akihiro Kanemitsu

The goal of this article is to study the equations and syzygies of embeddings of rational surfaces and certain Fano varieties. Given a rational surface X and an ample and base-point-free line bundle L on X, we give an optimal numerical…

Algebraic Geometry · Mathematics 2007-05-23 Francisco Javier Gallego , B. P. Purnaprajna

This is the first of a sequence of two papers. Here, a simple algebraic characterization of the Fano manifolds in the class of homogeneous toric bundles over a flag manifold G^C/P is provided in terms of symplectic data. The result of this…

Differential Geometry · Mathematics 2007-05-23 Fabio Podesta' , Andrea Spiro

Let $X\subset P^n$ be a complex projective manifold of degree $d$ and arbitrary dimension. The main result of this paper gives a classification of such manifolds (assumed moreover to be connected, non-degenerate and linearly normal) in case…

Algebraic Geometry · Mathematics 2007-05-23 Paltin Ionescu

In continuation of our work in Comm. in Algebra, vol. 28 (2000), we study ramified coverings of projective manifolds, in particular over Fano manifolds and investigate positivity properties of the associated vector bundle. Moreover we study…

Algebraic Geometry · Mathematics 2007-05-23 Thomas Peternell , Andrew Sommese

Motivated by the problem of classifying toric $2$-Fano manifolds, we introduce a new invariant for smooth projective toric varieties, the minimal projective bundle dimension. This invariant $m(X)\in\{1, \dots,\dim(X)\}$ captures the minimal…

Let $X$ be an $n$-dimensional complex Fano manifolds $(n\geq 3)$. Assume that $X$ contains a divisor $A$, which is isomorphic to a rational homogeneous space with Picard number one, such that the conormal bundle $\mathscr{N}^*_{A/X}$ is…

Algebraic Geometry · Mathematics 2021-07-30 Jie Liu

We describe the structure of regular codimension $1$ foliations with numerically projectively flat tangent bundle on complex projective manifolds of dimension at least $4$. Along the way, we prove that either the normal bundle of a regular…

Algebraic Geometry · Mathematics 2024-01-09 Stéphane Druel

We study rational curves on general Fano hypersurfaces in projective space, mostly by degenerating the hypersurface along with its ambient projective space to reducible varieties. We prove results on existence of low-degree rational curves…

Algebraic Geometry · Mathematics 2020-03-11 Ziv Ran

Let $X$ be a smooth projective variety defined over an algebraically closed field of positive characteristic $p$ whose tangent bundle is nef. We prove that $X$ admits a smooth morphism $X \to M$ such that the fibers are Fano varieties with…

Algebraic Geometry · Mathematics 2020-12-18 Akihiro Kanemitsu , Kiwamu Watanabe

We consider the problem to determine which blow-ups along subvarieties in products of two projective spaces are log Fano. By describing the nef cones of such blow-ups with special centers, we give a partial classification result. For each…

Algebraic Geometry · Mathematics 2018-09-25 Toru Tsukioka

We study complex projective manifolds X that admit surjective endomorphisms f:X->X of degree at least two. In case f is etale, we prove structure theorems that describe X. In particular, a rather detailed description is given if X is a…

Algebraic Geometry · Mathematics 2007-06-22 Marian Aprodu , Stefan Kebekus , Thomas Peternell

The symmetric projective varieties of rank one are all smooth and Fano by a classic result of Akhiezer. We classify the locally factorial (respectively smooth) projective symmetric $G$-varieties of rank 2 which are Fano. When $G$ is…

Algebraic Geometry · Mathematics 2010-12-22 Alessandro Ruzzi

We investigate homological stability for the space of sections of Fano fibrations over curves in the context of weak approximation, and establish it for projective bundles, as well as for conic and quadric surface bundles over curves.

Algebraic Geometry · Mathematics 2025-09-16 Sho Tanimoto , Yuri Tschinkel

We propose conjectural semiorthogonal decompositions for Fano schemes of linear subspaces on intersections of two quadrics, in terms of symmetric powers of the associated hyperelliptic (resp. stacky) curve. When the intersection is…

Let X be a simply connected projective manifold with nef anticanonical bundle. We prove that X is a product of a rationally connected manifold and a manifold with trivial canonical bundle. As an application we describe the MRC fibration of…

Algebraic Geometry · Mathematics 2017-06-28 Junyan Cao , Andreas Höring

K{\"u}chle classified the Fano fourfolds that can be obtained as zero loci of global sections of homogeneous vector bundles on Grassmannians. Surprisingly, his classification exhibits two families of fourfolds with the same discrete…

Algebraic Geometry · Mathematics 2015-02-03 Laurent Manivel