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Related papers: Extension of sections via adjoint ideals

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In this paper we study the problem of extension of holomorphic sections of line bundles/vector bundles from reduced unions of strata of divisors. An extension theorem of Ohsawa--Takegoshi type is proved. As consequences we deduce several…

Algebraic Geometry · Mathematics 2019-08-30 Chen-Yu Chi

The effective freeness in Fujita's conjecture states that, for an ample line bundle $L$ on a complex projective manifold $X$, the adjoint bundle $K_X\otimes L^{\otimes m}$ is globally generated when $m \geq \dim_{\mathbb C} X + 1$.…

Algebraic Geometry · Mathematics 2024-11-26 Tsz On Mario Chan

This paper stresses the strong link between the existence of partial holomorphic connections on the normal bundle of a foliation seen as a quotient of the ambient tangent bundle and the extendability of a foliation to an infinitesimal…

Complex Variables · Mathematics 2015-01-14 Isaia Nisoli

In this paper, I prove a very general extension theorem for log pluricanonical systems. The main application of this extension theorem is (together with Kawamata's subadjunction theorem) to give an optimal subadjunction theorem which…

Algebraic Geometry · Mathematics 2007-11-05 Hajime Tsuji

The main purpose of this paper is to generalize the celebrated L${}^2$ extension theorem of Ohsawa-Takegoshi in several directions : the holomorphic sections to extend are taken in a possibly singular hermitian line bundle, the subvariety…

Algebraic Geometry · Mathematics 2017-05-24 Junyan Cao , Jean-Pierre Demailly , Shin-Ichi Matsumura

We prove a theorem on the extension of holomorphic sections of powers of adjoint bundles from submanifolds of complex codimension 1 having non-trivial normal bundle. The first such result, due to Takayama, considers the case where the…

Complex Variables · Mathematics 2014-01-14 Dror Varolin

We give the new effective criterion for the global generation of the adjoint bundle on normal surfaces with a boundary. We could make the invariant \delta small a bit more on log-terminal singular point, and then we could prove the theorem…

Algebraic Geometry · Mathematics 2007-05-23 Takeshi Kawachi

This treats the base-point-freeness of the adjoint bundles on normal surfaces with a boundary. This is an extension of the non-relative version of the theorem of Ein-Lazarsfeld-Masek and the theorem of Kawachi-Masek.

alg-geom · Mathematics 2008-02-03 Takeshi Kawachi

We prove a subadjunction theorem which relates the multi-adjoint linear system of the ambient space and the linear system of the restricted bundle on a subvariety.

Algebraic Geometry · Mathematics 2007-05-23 Hajime Tsuji

We prove an $L^2$ extension theorem of Ohsawa-Takegoshi type for extending holomorphic sections of line bundles from a subvariety which is given as a maximal log-canonical center of a pair and is of general codimension in a projective…

Algebraic Geometry · Mathematics 2008-08-01 Dano Kim

This note reviews the authors' approach to Fujino's conjecture, i.e. the injectivity theorem for lc pairs on compact K\"ahler manifolds, via the use of adjoint ideal sheaves coupled with the associated residue computations in their previous…

Complex Variables · Mathematics 2024-11-12 Tsz On Mario Chan , Young-Jun Choi

In this note we establish a new Fujita-type effective bound for the base point freeness of adjoint line bundles on a compact complex projective manifold of complex dimension $n$. The bound we obtain (approximately) differs from the linear…

Algebraic Geometry · Mathematics 2007-05-23 Gordon Heier

Given a projective variety X, a smooth divisor D, and semipositive line bundles (L_1,h_1),,...,(L_m,h_m), we consider the "multiply twisted pluricanonical bundle" F:=m(K_X+D)+L_1+...+L_m on X and F_D:=mK_D+(L_1+...+L_m)|_D. Let I_j be the…

Algebraic Geometry · Mathematics 2011-10-11 Chen-Yu Chi , Chin-Lung Wang , Sz-Sheng Wang

The main result of the present article is a (practically optimal) criterium for the pseudoeffectivity of the twisted relative canonical bundles of surjective projective maps. Our theorem has several applications in algebraic geometry; to…

Algebraic Geometry · Mathematics 2012-10-30 Bo Berndtsson , Mihai Paun

The construction of sections of bundles with prescribed jet values plays a fundamental role in problems of algebraic and complex geometry. When the jet values are prescribed on a positive dimensional subvariety, it is handled by theorems of…

Complex Variables · Mathematics 2015-05-27 Yum-Tong Siu

In this paper, using the Atiyah-Ward equivalence and a theorem of Hitchin, one makes to correspond to certain bundles on the projective space, which are extensions of instanton bundles (in particular, these new bundles may have the first…

Algebraic Geometry · Mathematics 2007-05-23 C. Anghel , N. Manolache

We give effective bounds on the generation of pushforwards of log-pluricanonical bundles twisted by ample line bundles. This gives a partial answer to a conjecture proposed by Popa and Schnell. We prove two types of statements: first, more…

Algebraic Geometry · Mathematics 2018-10-30 Yajnaseni Dutta

We introduce the homogeneous and piecewise multilinear extensions and the eigenvalue problem for locally Lipschitz function pairs, in order to develop a systematic framework for relating discrete and continuous min-max problems. This also…

Combinatorics · Mathematics 2021-11-25 Jürgen Jost , Dong Zhang

In this paper, we show how to prove the basepoint-freeness for linear systems on irregular varieties inductively. For instance, we prove that Fujita's conjecture holds for irregular varieties of dimension $\mathnormal{n}$ with a nef…

Algebraic Geometry · Mathematics 2025-09-17 Houari Benammar Ammar

Using $L^2$-methods for the $\bar\partial$-equation we prove that the Ohsawa-Takegoshi extension theorem also holds for holomorphic sections of a vector bundle, over compact K\"ahler manifolds. We then proceed to show that the conditions…

Complex Variables · Mathematics 2014-05-08 Hossein Raufi
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