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Related papers: Seshadri fibrations of algebraic surfaces

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Let $X$ be a smooth complex projective curve and let $E$ be a vector bundle on $X$ which is not semistable. We consider a flag bundle $\pi: \text{Fl}(E) \to X$ parametrizing certain flags of fibers of $E$. The dimensions of the successive…

Algebraic Geometry · Mathematics 2024-04-10 Krishna Hanumanthu , Jagadish Pine

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

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

We introduce the Seshadri region of a subvariety, a convex region packaging the classical Seshadri constants with respect to every line bundle simultaneously. We develop the theory of Seshadri regions as a measure of positivity along…

Algebraic Geometry · Mathematics 2025-12-08 Juliette Bruce , Lauren Cranton Heller , Mahrud Sayrafi , Alexandra Seceleanu

We study a Seshadri constant at a general point on a rational surface whose anticanonical linear system contains a pencil. First, we describe a Seshadri constant of an ample line bundle on such a rational surface explicitly by the numerical…

Algebraic Geometry · Mathematics 2013-07-16 Taro Sano

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 this paper we consider the question of when Seshadri constants on abelian surfaces are integers. Our first result concerns self-products $E\times E$ of elliptic curves: If $E$ has complex multiplication in $\Z[i]$ or in…

Algebraic Geometry · Mathematics 2019-09-26 Thomas Bauer , Felix Fritz Grimm , Maximilian Schmidt

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

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

We prove that the Seshadri constant of a polarized abelian variety is equal to the Seshadri constant of its abelian subvariety if the Seshadri constant is relatively small with respect to its degree, or it contains an abelian divisor which…

Algebraic Geometry · Mathematics 2022-05-27 Rikito Ohta

Let $X$ be a smooth variety and let $L$ be an ample line bundle on $X$. If $\pi^{alg}_{1}(X)$ is large, we show that the Seshadri constant $\epsilon(p^{*}L)$ can be made arbitrarily large by passing to a finite \'etale cover…

Complex Variables · Mathematics 2019-02-25 Gabriele Di Cerbo , Luca F. Di Cerbo

We develop a new approach towards obtaining lower bounds of the Seshadri constants of ample adjoint divisors on smooth projective varieties $X$ in arbitrary characteristic. Let $x\in X$ be a closed point and $A$ an ample divisor on $X$. If…

Algebraic Geometry · Mathematics 2026-01-27 Linus Rösler

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

Algebraic Geometry · Mathematics 2007-11-06 Tomasz Szemberg

The purpose of this paper is to explicitly compute the Seshadri constants of all ample line bundles on fake projective planes. The proof relies on the theory of the Toledo invariant, and more precisely on its characterization of…

Complex Variables · Mathematics 2016-10-04 Luca F. Di Cerbo

The goal of this note is to study a conjectural picture on lower bounds of Seshadri constants of indecomposable polarized abelian varieties. This is inspired by some ideas of Debarre on the subject and the author's previous work on syzygies…

Algebraic Geometry · Mathematics 2023-12-05 Victor Lozovanu

Given a smooth complex projective variety $X$ and an ample line bundle $L$ on $X$. Fix a point $x\in X$. We consider the question, are there conditions which guarantee the maxima of the Seshadri constant of $L$ at $x$, i.e $\eps(L,x)=\root…

alg-geom · Mathematics 2008-02-03 Andreas Steffens

Let $L$ be a nef line bundle on a smooth complex projective variety $X$ of dimension $n$. Demailly has introduced a very interesting invariant --- the Seshadri constant $\epsilon(L,x)$ --- which in effect measures how positive $L$ is…

alg-geom · Mathematics 2008-02-03 Lawrence Ein , Oliver Küchle , Robert Lazarsfeld

We compare the deformation theory and the analytic structure of the Seiberg-Witten moduli spaces of a K\"ahler surface to the corresponding components of the Hilbert scheme, and show that they are isomorphic. Next we show how to compute the…

alg-geom · Mathematics 2008-02-03 Robert Friedman , John W. Morgan

We prove an analogue in higher dimensions of the classical Narasimhan-Seshadri theorem for strongly stable vector bundles of degree 0 on a smooth projective variety $X$ with a fixed ample line bundle $\Theta$. As applications, over fields…

Algebraic Geometry · Mathematics 2014-02-26 V. Balaji , A. J. Parameswaran

In this article, we derive bounds for values of the global geometry of locally tessellating planar graphs, namely, the Cheeger constant and exponential growth, in terms of combinatorial curvatures. We also discuss spectral implications for…

Spectral Theory · Mathematics 2008-05-13 Matthias Keller , Norbert Peyerimhoff