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Related papers: A Nonvanishing Conjecture for Cotangent Bundles

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We prove the Shafarevich conjecture for varieties with globally generated cotangent bundle, subject to mild numerical conditions.

Algebraic Geometry · Mathematics 2025-03-27 Thomas Krämer , Marco Maculan

The aim of this article is to establish the notion of bundle-type quasitoric manifolds and provide two classification results on them: (1) ($\mathbb{C}P^2\sharp\mathbb{C}P^2$)-bundle type quasitoric manifolds are weakly equivariantly…

Algebraic Topology · Mathematics 2017-02-08 Sho Hasui

Nonvanishing theorems play a central role in birational geometry, since they derive geometric consequences from numerical information and constitute a crucial step towards abundance and semiampleness problems. General nonvanishing…

Algebraic Geometry · Mathematics 2025-10-22 Andreas Höring , Vladimir Lazić , Christian Lehn

Given a complex projective surface with an ADE singularity and p_{g}=0, we construct ADE bundles over it and its minimal resolution. Furthermore, we descibe their minuscule representation bundles in terms of configurations of (reducible)…

Algebraic Geometry · Mathematics 2013-01-04 Yunxia Chen , Naichung Conan Leung

We prove an effective vanishing theorem for direct images of log pluricanonical bundles of projective semi-log canonical pairs. As an application, we obtain a semipositivity theorem for direct images of relative log pluricanonical bundles…

Algebraic Geometry · Mathematics 2018-02-16 Osamu Fujino

We prove that smooth, projective, $K$-trivial, weakly ordinary varieties over a perfect field of characteristic $p>0$ are not geometrically uniruled. We also show a singular version of our theorem, which is sharp in multiple aspects. Our…

Algebraic Geometry · Mathematics 2020-09-11 Zsolt Patakfalvi , Maciej Zdanowicz

In this short note, we prove a Tamarkin-type separation theorem for possibly non-compact subsets in cotangent bundles.

Symplectic Geometry · Mathematics 2025-07-01 Yuichi Ike , Tatsuki Kuwagaki

In this paper, we investigate Murre's conjectures on the structure of rational Chow groups and exhibit explicit Chow--Kuenneth projectors for some examples. More precisely, the examples we study are the varieties which have a nef tangent…

Algebraic Geometry · Mathematics 2007-06-13 Jaya NN Iyer

In this paper we study the cohomology of tensor products of symmetric powers of the cotangent bundle of complete intersection varieties in projective space. We provide an explicit description of some of those cohomology groups in terms of…

Algebraic Geometry · Mathematics 2014-07-01 Damian Brotbek

In this paper we study the geometrical structures on the cotangent bundle using the notions of adapted tangent structure and regular vector fields. We prove that the dynamical covariant derivative on $T^{*}M$ fix a nonlinear connection for…

Differential Geometry · Mathematics 2016-04-04 Liviu Popescu

For X a compact Riemann surface of positive genus, the strange duality conjecture predicts that the space of sections of certain theta bundle on moduli of bundles of rank r and level k is naturally dual to a similar space of sections of…

Algebraic Geometry · Mathematics 2007-05-23 Prakash Belkale

We prove that any minimal weak symplectic filling of the canonical contact structure on the unit cotangent bundle of a nonorientable closed surface other than the real projective plane is s-cobordant rel boundary to the disk cotangent…

Geometric Topology · Mathematics 2018-03-30 Youlin Li , Burak Ozbagci

On a projective surface it is well-known that the set of curves orthogonal to a nef line bundle is either finite or uncountable. We show that this dichotomy fails in higher dimension by constructing a nef line bundle on a threefold which is…

Algebraic Geometry · Mathematics 2014-10-17 John Lesieutre , John Christian Ottem

In this note, we obtain a number of results related to the hard Lefschetz theorem for pseudoeffective line bundles, due to Demailly, Peternell and Schneider. Our first result states that the holomorphic sections produced by the theorem are…

Algebraic Geometry · Mathematics 2020-05-14 Xiaojun Wu

This is a continuation of our first paper in [WY16]. There are two purposes of this paper: One is to give a proof of the main result in [WY16] without going through the argument depending on numerical effectiveness. The other one is to…

Differential Geometry · Mathematics 2016-09-07 Damin Wu , Shing-Tung Yau

In this paper, we introduce the notion of a super tangent bundle of a manifold, and extend the basic notions of differential geometry such as differential forms, exterior derivation, connection, metric and divergence on manifolds that…

Differential Geometry · Mathematics 2020-11-17 Naser Boroojerdian

We show that simply connected projective manifolds in characteristic $p>0$ have no nontrivial stratified bundles. This gives a positive answer to a conjecture by D. Gieseker. The proof uses Hrushovski's theorem on periodic points.

Algebraic Geometry · Mathematics 2015-05-13 Hélène Esnault , Vikram Mehta

We study a properly convex real projective manifold with (possibly empty) compact, strictly convex boundary, and which consists of a compact part plus finitely many convex ends. We extend a theorem of Koszul which asserts that for a compact…

Geometric Topology · Mathematics 2018-03-28 Daryl Cooper , Darren Long , Stephan Tillmann

In this note we address the following kind of question: let X be a smooth, irreducible, projective surface and D a divisor on X$satisfying some sort of positivity hypothesis, then is there some multiple of D depending only on X which is…

Toric hyperk{\"a}hler manifolds are quaternion analog of toric varieties. Bielawski pointed out that they can be glued by cotangent bundles of toric varieties. Following his idea, viewing both toric varieties and toric hyperk{\"a}her…

Differential Geometry · Mathematics 2015-03-18 Craig van Coevering , Wei Zhang