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Related papers: Moving curves and Seshadri constants

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We give the lower bound on Seshadri constants for the case of very ample line bundles on threefolds. We consider the situation when the Seshadri constant is strictly less than 2 and give a version of Bauer's theorem \cite[Theorem 2.1]{B1}…

Algebraic Geometry · Mathematics 2008-12-16 Kungho Chan

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

In this paper, we consider the intensity surface of a 2D image, we study the evolution of the symmetry sets (and medial axes) of 1-parameter families of iso-intensity curves. This extends the investigation done on 1-parameter families of…

Differential Geometry · Mathematics 2009-12-02 Andre Diatta , Peter Giblin

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

A new family of maximal curves over a finite field is presented and some of their properties are investigated.

Algebraic Geometry · Mathematics 2007-11-06 Massimo Giulietti , Gabor Korchmaros

We study asymptotic invariants of linear series on surfaces with the help of Newton-Okounkov polygons. Our primary aim is to understand local positivity of line bundles in terms of convex geometry. We work out characterizations of ample and…

Algebraic Geometry · Mathematics 2018-04-04 Alex Küronya , Victor Lozovanu

We investigate minimal surfaces passing a given curve in $R^{3}$. Using the Frenet frame of a given curve and isothermal parameter, we derive the necessary and sufficient condition for minimal surface. Also we derive the parametric…

Differential Geometry · Mathematics 2015-08-12 Sedat Kahyaoğlu , Emin Kasap

We study Seshadri constants of certain ample vector bundles on projective varieties. Our main motivation is the following question: Under what conditions are the Seshadri constants of ample vector bundles at least 1 at all points of the…

Algebraic Geometry · Mathematics 2023-08-09 Indranil Biswas , Krishna Hanumanthu , Snehajit Misra

We provide a lower bound on the degree of curves of the projective plane $\mathbb{P}^2$ passing through the centers of a divisorial valuation $\nu$ of $\mathbb{P}^2$ with prescribed multiplicities, and an upper bound for the Seshadri-type…

Algebraic Geometry · Mathematics 2024-05-07 Carlos Galindo , Francisco Monserrat , Carlos-Jesús Moreno-Ávila , Elvira Pérez-Callejo

We investigate the behaviour of vertices and inflexions on 1-parameter families of curves on smooth surfaces in the 3-space, which include a singular member. In particular, we discuss the context where the curves evolve as sections of a…

Differential Geometry · Mathematics 2014-02-24 Andre Diatta , Peter J. Giblin

We study crossing numbers for systoles of congruence surfaces. Taken as a family of curves on a family of surfaces, we show that the growth rate of their intersection is optimally small among all sets of curves of the same cardinality lying…

Geometric Topology · Mathematics 2025-08-29 Claire Burrin , Hugo Parlier

We obtain a coarse relationship between geometric intersection numbers of curves and the sum of their subsurface projection distances with explicit quasi-constants. By using this relationship, we give applications in the studies of the…

Geometric Topology · Mathematics 2017-09-12 Yohsuke Watanabe

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

We establish a family of parametric isoperimetric-type inequalities with multiple geometric quantities for closed convex curves. These inequalities hold under certain parameter conditions. We also prove the equality conditions. Some new…

Differential Geometry · Mathematics 2026-05-28 Heran Zhao

Let $X$ be a smooth complex projective curve, and let $E$ be a vector bundle on $X$ which is not semistable. For a suitably chosen integer $r$, let $\text{Gr}(E)$ be the Grassmann bundle over $X$ that parametrizes the quotients of the…

Algebraic Geometry · Mathematics 2019-05-24 Indranil Biswas , Krishna Hanumanthu , D. S. Nagaraj , Peter E. Newstead

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

A broadly applicable geometric approach for constructing nef divisors on blow ups of algebraic surfaces at n general points is given; it works for all surfaces in all characteristics for any n. This construction is used to obtain…

Algebraic Geometry · Mathematics 2007-05-23 Brian Harbourne

The traveling waves for surface diffusion of plane curves are studied. We consider an evolving plane curve with two endpoints, which can move freely on the x-axis with generating constant contact angles. For the evolution of this plane…

Analysis of PDEs · Mathematics 2019-08-26 Takashi Kagaya , Yoshihito Kohsaka

We study equisingular deformation problems for curves and surfaces in algebraic families, with particular emphasis on situations where nodal behavior is no longer generic. Extending classical Severi theory, we develop deformation--theoretic…

Algebraic Geometry · Mathematics 2026-03-03 Mounir Nisse

We study the local equivalence problems of curves and surfaces in three dimensional Heisenberg group via Cartans method of moving frames and Lie groups, and find a complete set of invariants for curves and surfaces. For surfaces, in terms…

Differential Geometry · Mathematics 2013-01-29 Hung-Lin Chiu , Sin-Hua Lai