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Related papers: Lemmes de multiplicites et constante de Seshadri

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So far, Seshadri constants on abelian surfaces are completely understood only in the cases of Picard number one and on principally polarized abelian surfaces with real multiplication. Beyond that, there are partial results for products of…

Algebraic Geometry · Mathematics 2022-04-14 Maximilian Schmidt

Starting with the pioneering work of Ein and Lazarsfeld restrictions on values of Seshadri constants on algebraic surfaces have been studied by many authors. In the present note we show how approximation involving continued fractions…

Algebraic Geometry · Mathematics 2017-06-29 Lucja Farnik , Tomasz Szemberg , Justyna Szpond , Halszka Tutaj-Gasinska

Suppose D is an effective divisor on a smooth projective algebraic variety X. For each point x of X we associate a numberical invariant called the moving Seshadri constant of D at x which is a numerical measure of positivity of the divisor…

Algebraic Geometry · Mathematics 2007-05-23 Michael Nakamaye

We establish formulas for the constant factor in several asymptotic estimates related to the distribution of integer and polynomial divisors. The formulas are then used to approximate these factors numerically.

Number Theory · Mathematics 2018-09-19 Andreas Weingartner

The aim of this note is to study local and global Seshadri constants for a family of smooth surfaces with prescribed polarization. We shall first observe that given $\alpha$ being smaller than the square root of the degree of polarization,…

Algebraic Geometry · Mathematics 2007-05-23 Keiji Oguiso

We refine results of Hwang, Keum and Szemberg, Tutaj-Gasinska which relate local invariants - Seshadri constants - of ample line bundles on surfaces to the global geometry - fibration structure. We show that the same picture emerges when…

Algebraic Geometry · Mathematics 2007-09-18 Wioletta Syzdek , Tomasz Szemberg

We propose improvements in numerical evaluation of symmetric stable density and its partial derivatives with respect to the parameters. They are useful for more reliable evaluation of maximum likelihood estimator and its standard error.…

Statistics Theory · Mathematics 2007-06-13 Muneya Matsui , Akimichi Takemura

Given an etale quotient q:X->Y of smooth projective varieties we relate the simple Seshadri constant of a line bundle M on Y with the multiple Seshadri constant of q*M in the points of the fiber. We apply this method to compute the Seshadri…

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

In this paper we will propose a new method to investigate Seshadri constants, namely by means of (nested) Hilbert schemes. This will allow us to use the geometry of the latter spaces, for example the computations of the nef cone via…

Algebraic Geometry · Mathematics 2024-09-17 Jonas Baltes

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

Fujita's conjecture is known to be false in positive characteristic. We conjecture and give an approach to a new variant of Fujita's conjecture for the basepoint-freeness, very ampleness, and jet ampleness of linear systems of the form…

Algebraic Geometry · Mathematics 2026-03-24 Takumi Murayama

We find the precise growth of some invariant metrics near a point on the boundary of a domain where the Levi form has at least one negative eigenvalue. We also introduce a new invariant pseudometric which is convenient in this context, and…

Complex Variables · Mathematics 2014-05-23 Nguyen Quang Dieu , Nikolai Nikolov , Pascal J. Thomas

We prove multiplier theorems on rank one noncompact symmetric spaces which improve aspects of existing results. A common theme of our main results is that we partially drop specific assumptions on the multiplier function such as a…

Functional Analysis · Mathematics 2023-05-11 Błażej Wróbel

We improve constants in the Rademacher-Menchov inequality.

Probability · Mathematics 2007-05-23 Witold Bednorz

We study the Seshadri constants on geometrically ruled surfaces. The unstable case is completely solved. Moreover, we give some bounds for the stable case. We apply these results to compute the Seshadri constant of the rational and elliptic…

Algebraic Geometry · Mathematics 2016-09-07 Luis Fuentes Garcia

The problem of estimating the multiplicity of the zero of a polynomial when restricted to the trajectory of a non-singular polynomial vector field, at one or several points, has been considered by authors in several different fields. The…

Dynamical Systems · Mathematics 2016-02-10 Gal Binyamini

We define and study a version of Seshadri constant for ample line bundles in positive characteristic. We prove that lower bounds for this constant imply the global generation or very ampleness of the corresponding adjoint line bundle. As a…

Algebraic Geometry · Mathematics 2014-05-06 Mircea Mustata , Karl Schwede

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

In the present paper we are concerned with the possible values of Seshadri constants. While in general every positive rational number appears as the local Seshadri constant of some ample line bundle, we point out that for adjoint line…

Algebraic Geometry · Mathematics 2010-11-23 Thomas Bauer , Tomasz Szemberg

This paper studies the Seshadri constant of an ample line bundle at a very general point, seeking a very slight improvement on the result of Ein, Kuchle, and Lazarsfeld. The main point is that couting jets more carefully yields a better…

Algebraic Geometry · Mathematics 2007-05-23 Michael Nakamaye