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相关论文: Bounds for Seshadri Constants

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In this note we show that the multipoint Seshadri constant determines the maximum possible radii of embeddings of K\"ahler balls and vice versa.

代数几何 · 数学 2019-05-09 Aeran Fleming

The main purpose of the note is to exclude the existence of certain submaximal curves in fake projective planes. This will lead to lower bounds on multipoint Seshadri constants of `fake' $\mathcal{O}(1)$ on fake projective planes.

代数几何 · 数学 2021-04-21 Piotr Pokora , Halszka Tutaj-Gasinska

A necessary and sufficient condition is given for semi-ampleness of a numerically effective (nef) and big line bundle in positive characteristic. One application is to the geometry of the universal stable curve over M_g, specifically, the…

代数几何 · 数学 2016-09-07 Seán Keel

In \cite{NNM} the author with A. N\'emethi computed the multiplicity of generic surface singularities, the formula is purely topological computable from the resolution graph of the surface singularity. In the present paper we extend the…

代数几何 · 数学 2021-12-30 János Nagy

We study the Hardy inequality when the singularity is placed on the boundary of a bounded domain in $\mathbb{R}^n$ that satisfies both an interior and exterior ball condition at the singularity. We obtain the sharp Hardy constant $n^2/4$ in…

偏微分方程分析 · 数学 2018-04-06 Gerassimos Barbatis , Stathis Filippas , Achilles Tertikas

The Bounded Negativity Conjecture predicts that for any smooth complex surface $X$ there exists a lower bound for the selfintersection of reduced divisors on $X$. This conjecture is open. It is also not known if the existence of such a…

The aim of this note is to shed some light on the relationships among some notions of positivity for vector bundles that arose in recent decades. Our purpose is to study several of the positivity notions studied for vector bundles with some…

We introduce and study the successive minima of line bundles on proper algebraic varieties. The first (resp. last) minima are the width (resp. Seshadri constant) of the line bundle at very general points. The volume of the line bundle is…

代数几何 · 数学 2020-02-18 Florin Ambro , Atsushi Ito

A standard monomial theory for Schubert varieties is constructed exploiting (1) the geometry of the Seshadri stratifications of Schubert varieties by their Schubert subvarieties and (2) the combinatorial LS-path character formula for…

代数几何 · 数学 2024-04-10 Rocco Chirivì , Xin Fang , Peter Littelmann

We give degree lower bounds for quotient line bundles of the lowest piece of a Hodge module induced by a complex variation of Hodge structures outside a simple normal crossing divisor, beyond the unipotent variation case. This note aims to…

代数几何 · 数学 2026-05-14 Ze Yun

In this paper, we study when positivity conditions of vector bundles are preserved by extension. We prove that an extension of a big (resp. pseudo-effective) line bundle by an ample (resp. a nef) vector bundle is big (resp.…

代数几何 · 数学 2023-12-18 Sho Ejiri , Osamu Fujino , Masataka Iwai

We give equivalent descriptions for the augmented and diminished base loci of vector bundles in characteristic zero. We show that these base loci behave well under pullback, tensor product, and direct sum. Pathological behavior is observed…

代数几何 · 数学 2023-03-24 Mihai Fulger , Nabanita Ray

Let $Y$ be a submanifold of dimension $y$ of a polarized complex manifold $(X,A)$ of dimension $k\geq 3$, with $1\leq y\leq k-1$. We define and study two positivity conditions on $Y$ in $(X,A)$, called Seshadri $A$-bigness and (a stronger…

代数几何 · 数学 2011-09-23 Lucian Badescu , Mauro C. Beltrametti

We propose a linear version of the weighted bounded negativity conjecture. It considers a smooth projective surface $X$ over an algebraically closed field of characteristic zero and predicts the existence of a common lower bound on…

代数几何 · 数学 2025-01-27 Carlos Galindo , Francisco Monserrat , Elvira Pérez-Callejo

In analogy to the relation between symplectic packings and symplectic blow ups we show that multiple point Seshadri constants on projective complex surfaces can be calculated as the supremum of radii of multiple K\"ahler ball embeddings.

代数几何 · 数学 2016-09-13 Thomas Eckl

When a reductive group $G$ acts linearly on a complex projective scheme $X$ there is a stratification of $X$ into $G$-invariant locally closed subschemes, with an open stratum $X^{ss}$ formed by the semistable points in the sense of…

代数几何 · 数学 2014-02-26 Victoria Hoskins , Frances Kirwan

We prove that classes of rational curves on very general Enriques surfaces are always $2$-divisible. As a consequence, we prove that the Seshadri constant of any big and nef line bundle on a very general Enriques surface coincides with the…

代数几何 · 数学 2024-07-01 Concettina Galati , Andreas Leopold Knutsen

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…

复变函数 · 数学 2014-05-23 Nguyen Quang Dieu , Nikolai Nikolov , Pascal J. Thomas

In this article we study smooth families of stratified bundles in positive characteristic and the variation of their monodromy group.Our aim is, in particular, to strengthen the weak form of the positive equicharacteristic $p$-curvature…

代数几何 · 数学 2015-01-06 Giulia Battiston

Stability and boundedness analysis for vector nonlinear systems with variable delays and coefficients remains challenging due to the conservatism of existing methods. Moreover, estimates of the transient behavior of solution norms remain…

动力系统 · 数学 2026-01-13 Mark A. Pinsky