English
Related papers

Related papers: On Pseudo-Effectivity of the Second Chern Classes …

200 papers

Let $C$ be a smooth curve of genus $g \geq 1$ and let $C^{(2)}$ be its second symmetric product. In this note we prove that if $C$ is very general, then the blow-up of $C^{(2)}$ at a very general point has non-polyhedral pseudo-effective…

Algebraic Geometry · Mathematics 2022-10-24 Antonio Laface , Luca Ugaglia

In light of Sen's weak coupling limit of F-theory as a type IIB orientifold, the compatibility of the tadpole conditions leads to a non-trivial identity relating the Euler characteristics of an elliptically fibered Calabi-Yau fourfold and…

High Energy Physics - Theory · Physics 2012-04-11 Paolo Aluffi , Mboyo Esole

The aim of this note is to point out that Chern characters can be computed using curvatures o ``super-connections up to homotopy'. We also present an application to the vanishing theorem for Lie algebroids which is at the origin of new…

Differential Geometry · Mathematics 2007-05-23 Marius Crainic

We report in this survey some new results concerning noncommutative Chern characters: construction and the cases when they are exactly computed. The major result indicates some clear relation of these noncommutative objects and their…

Quantum Algebra · Mathematics 2007-05-23 Do Ngoc Diep

This note mainly studies the generic finiteness of \phi_m of a complex projective 3-fold of general type. A new result on the classification to bicanonical pencil for Gorenstein 3-folds is attached in the last section.

Algebraic Geometry · Mathematics 2007-05-23 Meng Chen

In this paper and in its sequel [BKLV], we investigate the cone ${\rm Pseff}_n(C_d)$ of pseudoeffective $n$-cycles in the symmetric product $C_d$ of a smooth curve $C$. In the present paper, we study the convex-geometric properties of the…

Algebraic Geometry · Mathematics 2023-01-18 Francesco Bastianelli , Alexis Kouvidakis , Angelo Felice Lopez , Filippo Viviani

We bound the second Chern class of the tangent sheaf of a codimension-one foliation. Equivalently, we bound the degree of the pure codimension-two part of the singular scheme. In particular, for a degree-$d$ foliation on the projective…

Algebraic Geometry · Mathematics 2026-01-21 Alan Muniz

The existence and continuity for the Calderon projector of the perturbed odd signature operator on a 3-manifold is established. As an application we give a new proof of a result of Taubes relating the mod 2 spectral flow of a family of…

Geometric Topology · Mathematics 2007-05-23 Benjamin Himpel , Paul Kirk , Matthias Lesch

We construct Chern-Weil classes on infinite dimensional vector bundles with structure group contained in the algebra $\cl[\leq 0](M, E)$ of non-positive order classical pseudo-differential operators acting on a finite rank vector bundle $E$…

Differential Geometry · Mathematics 2007-05-23 Sylvie Paycha , Steven Rosenberg

We give a construction of the second Chern number of a vector bundle over a smooth projective surface by means of adelic transition matrices for the vector bundle. The construction does not use an algebraic $K$-theory and depends on the…

Algebraic Geometry · Mathematics 2019-01-01 D. V. Osipov

In this paper, we classify projective toric birational morphisms from Gorenstein toric 3-folds onto the 3-dimensional affine space with relatively ample anti-canonical divisors.

Algebraic Geometry · Mathematics 2007-05-23 Hiroshi Sato

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

Let $X$ be a nonsingular variety defined over an algebraically closed field of characteristic $0$, and $D$ be a free divisor with Jacobian ideal of linear type. We compute the Chern class of the sheaf of logarithmic derivations along $D$…

Algebraic Geometry · Mathematics 2017-10-18 Xia Liao

Let $\mathcal{F}$ be a foliation on a projective manifold $X$ with $-K_{\mathcal{F}}$ nef. Assume that either $\mathcal{F}$ is regular, or it has a compact leaf. We prove that there is a locally trivial fibration $f\colon X\to Y$, and a…

Algebraic Geometry · Mathematics 2023-06-22 Wenhao Ou

We prove Chern conjecture, which states that the Euler characteristic vanishes for closed flat affine manifolds. Our key innovation is a deformation argument for the Euler form.

Differential Geometry · Mathematics 2025-12-09 Mihail Cocos

Yan and Chen proved a weak Cartan-type second main theorem for holomorphic curves meeting hypersurfaces in projective space that included truncated counting functions. Here we give an explicit estimate for the level of truncation.

Complex Variables · Mathematics 2007-08-08 Ta Thi Hoai An , Ha Tran Phuong

This paper aims to develop a theory of projective and affine structures on higher-dimensional varieties in positive characteristic. This theory deals with Frobenius-projective and Frobenius-affine structures, which have been previously…

Algebraic Geometry · Mathematics 2026-05-19 Yasuhiro Wakabayashi

We generalize the Chern class relation for the transversal intersection of two nonsingular varieties to a relation for possibly singular varieties, under a 'splayedness' assumption. The relation is shown to hold for both the…

Algebraic Geometry · Mathematics 2019-08-15 Paolo Aluffi , Eleonore Faber

We investigate properties and describe examples of tilt-stable objects on a smooth complex projective threefold. We give a structure theorem on slope semistable sheaves of vanishing discriminant, and describe certain Chern classes for which…

Algebraic Geometry · Mathematics 2012-09-14 Jason Lo , Yogesh More

In this paper, we prove the ampleness conjecture and Serrano's conjecture for strictly nef divisors on K-trivial fourfolds. Specifically, we show that any strictly nef divisors on projective fourfolds with trivial canonical bundle and…

Algebraic Geometry · Mathematics 2024-01-11 Haidong Liu , Shin-ichi Matsumura
‹ Prev 1 4 5 6 7 8 10 Next ›