English
Related papers

Related papers: On Generalised Abundance, I

200 papers

Jet ampleness of line bundles generalizes very ampleness by requiring the existence of enough global sections to separate not just points and tangent vectors, but also their higher order analogues called jets. We give sharp bounds…

Algebraic Geometry · Mathematics 2021-07-13 José Luis González , Zhixian Zhu

In this paper we establish effective lower bounds on the degrees of the Debarre and Kobayashi conjectures. Then we study a more general conjecture proposed by Diverio-Trapani on the ampleness of jet bundles of general complete intersections…

Algebraic Geometry · Mathematics 2018-10-02 Ya Deng

The study of entire holomorphic curves contained in projective algebraic varieties is intimately related to fascinating questions of geometry and number theory -- especially through the concepts of curvature and positivity which are central…

Algebraic Geometry · Mathematics 2020-02-14 Jean-Pierre Demailly

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

The Bounded Height Conjecture of Bombieri, Masser, and Zannier states that for any sufficiently generic algebraic subvariety of a semiabelian $\overline{\mathbb{Q}}$-variety $G$ there is an upper bound on the Weil height of the points…

Number Theory · Mathematics 2020-07-01 Lars Kühne

In this paper, for compact K\"ahler manifolds with nef cotangent bundle, we study the abundance conjecture and the associated Iitaka fibrations. We show that, for a minimal compact K\"ahler manifold, the second Chern class vanishes if and…

Algebraic Geometry · Mathematics 2022-05-24 Masataka Iwai , Shin-ichi Matsumura

The main theorem of this paper is a result of estimated transversality with respect to stratifications of jet spaces in the approximately holomorphic category over an almost-complex manifold. The notion of asymptotic ampleness of complex…

Symplectic Geometry · Mathematics 2007-05-23 Denis Auroux

In this paper, we study the structure of projective space bundles whose relative anti-canonical line bundle is nef. As an application, we get a characterization of abelian varieties up to finite etale covering.

Algebraic Geometry · Mathematics 2011-10-10 Kazunori Yasutake

We study the relations between the triviality of the tangent bundle $TM$ and the generalized tangent bundle $\mathbb{T}M = TM\oplus T^*M$ of a manifold. We show that the generalized tangent bundle of a paralellizable manifold is trivial. We…

Differential Geometry · Mathematics 2026-05-18 Fernando Etayo , Pablo Gómez-Nicolás , Rafael Santamaría

We discuss logical links among uniformity conjectures concerning K3 surfaces and abelian varieties of bounded dimension defined over number fields of bounded degree. The conjectures concern the endomorphism algebra of an abelian variety,…

Number Theory · Mathematics 2021-12-14 Martin Orr , Alexei N. Skorobogatov , Yuri G. Zarhin

We study fundamental forms of algebraic varieties using the sheaves of principal parts of line bundles and establish a vanishing theorem for any order fundamental forms. We also give connection of fundamental forms with the higher order…

Algebraic Geometry · Mathematics 2023-04-18 Lawrence Ein , Wenbo Niu

Given a covering f: X \to Y of projective manifolds, we consider the vector bundle E on Y given as the dual of f_*(\O_X) / \O_Y. This vector bundles often has positivity properties, e.g. E is ample when Y is projective space by a theorem of…

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

Co lombeau's construction of generalized functions (in its special variant) is extended to a theory of generalized sections of vector bundles. As particular cases, generalized tensor analysis and exterior algebra are studied. A point value…

Functional Analysis · Mathematics 2007-05-23 Michael Kunzinger , Roland Steinbauer

This paper reproves a general form of the Green-Lazarsfeld 'generic vanishing' theorem and more recent strengthenings, as well as giving some new applications.

Algebraic Geometry · Mathematics 2007-05-23 Herbert Clemens , Christopher Hacon

We study the analytic and topological invariants associated with complex normal surface singularities. Our goal is to provide topological formulae for several discrete analytic invariants whenever the analytic structure is generic (with…

Algebraic Geometry · Mathematics 2019-09-17 János Nagy , András Némethi

Let X be a compact K\"ahler manifold such that the anticanonical bundle $-K_X$ is nef. A classical conjecture claims that the Albanese map is submersive. We prove this conjecture if the general fibre is a weak Fano manifold. If X is…

Algebraic Geometry · Mathematics 2017-10-30 Junyan Cao , Andreas Höring

We prove that a smooth complex projective threefold with a K\"ahler metric of negative holomorphic sectional curvature has ample canonical line bundle. In dimensions greater than three, we prove that, under equal assumptions, the nef…

Algebraic Geometry · Mathematics 2009-09-02 Gordon Heier , Steven S. Y. Lu , Bun Wong

In the last twenty years a number of papers appeared aiming to construct locally free replacements of the sheaf of principal parts for families of Gorenstein curves. The main goal of this survey is to present to the widest possible audience…

Algebraic Geometry · Mathematics 2019-07-17 Letterio Gatto , Andrea T. Ricolfi

In 1989 H. Tverberg proposed a quite general conjecture in Discrete geometry, which could be considered as the common basis for many results in Combinatorial geometry and at the same time as a discrete analogue of the common transversal…

Combinatorics · Mathematics 2007-05-23 Sinisa T. Vrecica

We prove several finiteness theorems for the normal bundles to souls in nonnegatively curved manifolds. More generally, we obtain finiteness results for open Riemannian manifolds whose topology is concentrated on compact domains of…

Differential Geometry · Mathematics 2007-05-23 Igor Belegradek , Vitali Kapovitch