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Related papers: Okounkov bodies and Seshadri constants

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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

Let $\pi: X_r \rightarrow \mathbb P^2$ be a blow up of $\mathbb P^2$ at $r$ distinct points $p_1,p_2,\dots, p_r$. We study lower bounds for Seshadri constants of ample line bundles on $X_r$. First, we consider the case when the points lie…

Algebraic Geometry · Mathematics 2025-09-15 Cyril J. Jacob

Given a nef and big line bundle $L$ on a projective variety $X$ of dimension $d \geq 2$, we prove that the Seshadri constant of $L$ at a very general point is larger than $(d+1)^{\frac{1}{d}-1}$. This slightly improves the lower bound $1/d$…

Algebraic Geometry · Mathematics 2022-03-15 François Ballaÿ

In this article we compute Seshadri constants of ample line bundles on the blowup of Hirzebruch surface $\mathbb{F}_e$ at $r\leqslant e+3$ very general points. Similarly, we compute Seshadri constants on the blowups of certain decomposable…

Algebraic Geometry · Mathematics 2025-01-10 Cyril J. Jacob , Bivas Khan , Ronnie Sebastian

We examine how the Seshadri constant of an ample line bundle at a very general point of an algebraic surface can carry important global geometric information about the surface. In particular, we obtain a numerical criterion for when a…

Algebraic Geometry · Mathematics 2007-05-23 Michael Nakamaye

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

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

Towards the boundary of the big cone, Newton-Okounkov bodies do not vary continuously and in fact the body of a boundary class is not well defined. Using the global Okounkov body one can nonetheless define a numerical invariant, the…

Algebraic Geometry · Mathematics 2016-07-14 William F. Sawin , David Schmitz

We define Seshadri constants for Higgs bundles on smooth projective varieties over algebraically closed fields of characteristic zero. This definition is inspired by and analogous to the notion of Seshadri constants for ordinary vector…

Algebraic Geometry · Mathematics 2026-05-26 Krishna Hanumanthu , Snehajit Misra , Nabanita Ray

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

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…

Let $X$ be a smooth projective variety. We construct partial Okounkov bodies associated to Hermitian pseudo-effective line bundles $(L,\phi)$ on $X$. We show that partial Okounkov bodies are universal invariants of the singularity of…

Algebraic Geometry · Mathematics 2025-06-11 Mingchen Xia

We consider the problem of lower bounding a generalized Minkowski measure of subsets of a convex body with a log-concave probability measure, conditioned on the set size. A bound is given in terms of diameter and set size, which is sharp…

Functional Analysis · Mathematics 2007-05-23 Ravi Montenegro

Let $X_r$ denote the blow-up of the hyperelliptic surface $X$ at $r$ very general points. In this paper, we first provide a criterion for the ampleness of a line bundle on $X_r$ and compare it with an existing result. We then study the…

Algebraic Geometry · Mathematics 2025-03-31 Praveen Kumar Roy

We show an arithmetic generalization of the recent work of Lazarsfeld-Mustata which uses Okounkov bodies to study linear series of line bundles. As applications, we derive a log-concavity inequality on volumes of arithmetic line bundles and…

Algebraic Geometry · Mathematics 2014-01-14 Xinyi Yuan

For a positive integer $n$, let $X_n \to X_{n-1} \to \ldots \to X_2 \to X_1 \to X_0$ be a Bott tower of height $n$, and let $L$ be a nef line bundle on $X_n$. We compute Seshadri constants $\varepsilon(X_n,L,x)$ of $L$ at any point $x \in…

Algebraic Geometry · Mathematics 2022-03-14 Indranil Biswas , Jyoti Dasgupta , Krishna Hanumanthu , Bivas Khan

In this article, we study Newton-Okounkov bodies on projective vector bundles over curves. Inspired by Wolfe's estimates used to compute the volume function on these varieties, we compute all Newton-Okounkov bodies with respect to linear…

Algebraic Geometry · Mathematics 2018-10-16 Pedro Montero

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

The purpose of this paper is to investigate the behaviour of certain asymptotic invariants of line bundles on projective surfaces. In particular, we describe the volume of line bundles and their destabilizing numbers.

Algebraic Geometry · Mathematics 2007-05-23 Thomas Bauer , Alex Kuronya , Tomasz Szemberg

In this paper we explore the connection between asymptotic base loci and Newton-Okounkov bodies associated to infinitesimal flags. Analogously to the surface case, we obtain complete characterizations of augmented and restricted base loci.…

Algebraic Geometry · Mathematics 2015-07-16 Alex Küronya , Victor Lozovanu