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Related papers: A remark on the irregularity complex

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We prove that the formal completion of a complex projective surface along a rigid smooth curve with trivial normal bundle determines the birational equivalence class of the surface.

Algebraic Geometry · Mathematics 2020-09-16 Jorge Vitório Pereira , Olivier Thom

This paper explores the cohomological consequences of the existence of moduli spaces for flat bundles with bounded rank and irregularity at infinity and gives unconditional proofs. Namely, we prove the existence of a universal bound for the…

Algebraic Geometry · Mathematics 2025-02-26 Haoyu Hu , Jean-Baptiste Teyssier

A stratified bundle is a vector bundle which is a D-module. We show that regular singularity of stratified bundles on smooth varieties in positive characteristic is preserved by pullback and that regular singularity can be checked on…

Algebraic Geometry · Mathematics 2015-03-18 Lars Kindler

We discuss the problem of classifying birational extremal contractions of smooth threefolds where the canonical bundle is trivial along the curves contracted, in the case when a divisor is contracted to a point. We prove the analytic…

Algebraic Geometry · Mathematics 2007-05-23 Csilla Tamás

A formula for the irregularity of a cyclic multiple plane associated to a branch curve that has arbitrary singularities and is transverse to the line at infinity is established. The irregularity is expressed as a sum of superabundances of…

Algebraic Geometry · Mathematics 2007-05-23 Daniel Naie

In this paper we consider the singularities of the varieties parameterizing stable vector bundles of fixed rank and degree with sections on a smooth curve of genus at least two. In particular, we extend results of Y. Laszlo, and of the…

Algebraic Geometry · Mathematics 2012-07-05 Sebastian Casalaina-Martin , Montserrat Teixidor i Bigas

In this short note, we show that, assuming a conjecture of Arcara and Miles, a line bundle on a smooth complex projective surface admits a deformed Hermitian-Yang-Mills metric if and only if it is stable in the ``large scaling limit" with…

Algebraic Geometry · Mathematics 2026-04-27 Yu-Wei Fan

We describe the moduli spaces of meromorphic connections on trivial holomorphic vector bundles over the Riemann sphere with at most one (unramified) irregular singularity and arbitrary number of simple poles as Nakajima's quiver varieties.…

Differential Geometry · Mathematics 2014-01-24 Kazuki Hiroe , Daisuke Yamakawa

Given a formal flat meromorphic connection over an excellent scheme over a field of characteristic zero, in a previous paper we established existence of good formal structures and a good Deligne-Malgrange lattice after suitably blowing up.…

Algebraic Geometry · Mathematics 2019-03-11 Kiran S. Kedlaya

We prove that every simplicial complex is the dual complex of some simple normal crossing divisor in a smooth variety. As an application, we simplify and extend the results of Kapovich--Koll\'ar (math.AG:1109.4047) on the existence of…

Algebraic Geometry · Mathematics 2013-01-08 János Kollár

A classical fact is that normal bundles of rational normal curves are well-balanced. We generalize this by proving that all Veronese normal bundles are slope semistable. We also determine the line bundle decomposition of the restriction of…

Algebraic Geometry · Mathematics 2024-11-26 Ray Shang

For $G$ a split semi-simple group scheme and $P$ a principal $G$-bundle on a relative curve $X\to S$, we study a natural obstruction for the triviality of $P$ on the complement of a relatively ample Cartier divisor $D \subset X$. We show,…

Algebraic Geometry · Mathematics 2018-01-16 Prakash Belkale , Najmuddin Fakhruddin

We study ample stable vector bundles on minimal rational surfaces. We give a complete classification of those moduli spaces for which the general stable bundle is both ample and globally generated. We also prove that if $V$ is any stable…

Algebraic Geometry · Mathematics 2021-07-22 Jack Huizenga , John Kopper

We point out that any stable generalized complex structure on a sphere bundle over a closed surface of genus at least two must be of constant type.

Differential Geometry · Mathematics 2025-01-17 Rafael Torres

We show that there exist flat surface bundles with closed leaves having non-trivial normal bundles. This leads us to compute the Abelianisation of surface diffeomorphism groups with marked points. We also extend a formula of Tsuboi that…

Geometric Topology · Mathematics 2014-10-01 Jonathan Bowden

We identify the holomorphic de Rham complex of the minimal extension of a meromorphic vector bundle with connexion on a compact Riemann surface X with the L^2 complex relative to a suitable metric on the bundle and a complete metric on the…

Algebraic Geometry · Mathematics 2007-05-23 Claude Sabbah

We determine the splitting (isomorphism) type of the normal bundle of a generic genus-0 curve with 1 or 2 components in any projective space, as well as the (sometimes nontrivial) way the bundle deforms locally with a general deformation of…

Algebraic Geometry · Mathematics 2007-05-23 Ziv Ran

In this paper we proof the existence of a linearization for singular principal G-bundles not depending on the base curve. This allow us to construct the relative compact moduli space of {\delta}-(semi)stable singular principal G-bundles…

Algebraic Geometry · Mathematics 2018-06-27 Ángel Luis Muñoz Castañeda

We show that principal bundles for a semisimple group on an arbitrary affine curve over an algebraically closed field are trivial, provided the order of $\pi_1$ of the group is invertible in the ground field, or if the curve has semi-normal…

Algebraic Geometry · Mathematics 2017-12-12 Prakash Belkale , Najmuddin Fakhruddin

We investigate the formal principle for holomorphic line bundles on neighborhoods of an analytic subset of a complex manifold mainly in the case where it can be realized as an open subset of a compact K\"ahler manifold. Our approach…

Complex Variables · Mathematics 2026-01-26 Takayuki Koike
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