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Related papers: Lemmes de multiplicites et constante de Seshadri

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In this article we study interpolation estimates on a special class of compactifications of commutative algebraic groups constructed by Serre. We obtain a large quantitative improvement over previous results due to Masser and the first…

Number Theory · Mathematics 2012-05-21 Stéphane Fischler , Michael Nakamaye

We give a method to estimate Seshadri constants on toric varieties at any point. By using the estimations and toric degenerations, we can obtain some new computations or estimations of Seshadri constants on non-toric varieties. In…

Algebraic Geometry · Mathematics 2013-02-01 Atsushi Ito

In this note we improve a result of Steffens on the lower bound for Seshadri constants in very general points of a surface with one-dimensional N\'eron-Severi space. We also show a multi-point counterpart of such a lower bound.

Algebraic Geometry · Mathematics 2011-04-08 Tomasz Szemberg

We study lower bounds on Seshadri constants at arbitrary points on surfaces with Picard number 1.

Algebraic Geometry · Mathematics 2007-11-06 Tomasz Szemberg

Seshadri constants are local invariants, introduced by Demailly, which measure the local positivity of ample line bundles. Recent interest in Seshadri constants stems on the one hand from the fact that bounds on Seshadri constants yield,…

Algebraic Geometry · Mathematics 2025-04-09 Thomas Bauer

We give a bound for the multiple Seshadri constants on surfaces with Picard number 1. The result is a natural extension of the bound of A. Steffens for simple Seshadri constants. In particular, we prove that the Seshadri constant…

Algebraic Geometry · Mathematics 2007-05-23 Luis Fuentes Garcia

One of Demailly's characterizations of Seshadri constants on ample line bundles works with Lelong numbers of certain positive singular hermitian metrics. In this note sections of multiples of the line bundle are used to produce such metrics…

Algebraic Geometry · Mathematics 2007-05-23 Thomas Eckl

Seshadri constants express the so called local positivity of a line bundle on a projective variety. They were introduced by Demailly. The original idea of using them towards a proof of the Fujita conjecture failed but they quickly became a…

Seshadri constants on abelian surfaces are fully understood in the case of Picard number one. Little is known so far for simple abelian surfaces of higher Picard number. In this paper we investigate principally polarized abelian surfaces…

Algebraic Geometry · Mathematics 2025-04-09 Thomas Bauer , Maximilian Schmidt

In this paper, we study a relation between Seshadri constants and degrees of defining polynomials. In particular, we compute the Seshadri constants on Fano varieties obtained as complete intersections in rational homogeneous spaces of…

Algebraic Geometry · Mathematics 2013-02-01 Atsushi Ito , Makoto Miura

In the present note, we focus on certain properties of special curves that might be used in the theory of multi-point Seshadri constants for ample line bundles on the complex projective plane. In particular, we provide three…

Algebraic Geometry · Mathematics 2023-01-10 Piotr Pokora

In the note we study the multipoint Seshadri constants of $\mathcal{O}_{\mathbb{P}^{2}_{\mathbb{C}}}(1)$ centered at singular loci of certain curve arrangements in the complex projective plane. Our first aim is to show that the values of…

Algebraic Geometry · Mathematics 2020-07-13 Marek Janasz , Piotr Pokora

In this note we contribute to the study of Seshadri constants on abelian and bielliptic surfaces. We specifically focus on bounds that hold on all such surfaces, depending only on the self-intersection of the ample line bundle under…

Algebraic Geometry · Mathematics 2020-08-19 Thomas Bauer , Łucja Farnik

In the paper we present an alternative approach to the boundedness of Seshadri constants (which measure the local positivity) of nef and big line bundles at a general point of a complex--projective variety. Our approach is based on the…

alg-geom · Mathematics 2008-02-03 Oliver Küchle , Andreas Steffens

We study Seshadri constants of ample line bundles on hyperelliptic surfaces. We obtain new lower bounds and compute the exact values of Seshadri constants in some cases. Our approach uses results of F. Serrano (1990), B. Harboune and J. Roe…

Algebraic Geometry · Mathematics 2015-02-13 Lucja Farnik

We develop a local positivity theory for movable curves on projective varieties similar to the classical Seshadri constants of nef divisors. We give analogues of the Seshadri ampleness criterion, of a characterization of the augmented base…

Algebraic Geometry · Mathematics 2018-09-10 Mihai Fulger

Working over C, we show that, apart possibly from a unique limit point, the possible values of multi-point Seshadri constant for general points on smooth projective surfaces form a discrete set. In addition to its theoretical interest, this…

Algebraic Geometry · Mathematics 2007-09-26 Brian Harbourne , Joaquim Roe

Let $X$ be a surface and let $L$ be an ample line bundle on $X$. We first obtain a lower bound for the Seshadri constant $\varepsilon(X,L,r)$, when $r \ge 3$. We then assume that $X$ is a ruled surface and study Seshadri constants on $X$ in…

Algebraic Geometry · Mathematics 2017-01-25 Krishna Hanumanthu , Alapan Mukhopadhyay

We introduce Seshadri constants for line bundles in a relative setting. They generalize the classical Seshadri constants of line bundles on projective varieties and their extension to vector bundles studied by Beltrametti-Schneider-Sommese…

Algebraic Geometry · Mathematics 2019-03-06 Mihai Fulger , Takumi Murayama

In "Seshadri fibrations of algebraic surfaces" [arXiv:0709.2592v1] we showed that if the multiple point Seshadri constants of an ample line bundle on a smooth projective surface in very general points satisfy certain inequality then the…

Algebraic Geometry · Mathematics 2008-06-10 Wioletta Syzdek , Tomasz Szemberg
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