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Related papers: A primer on Seshadri constants

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We consider Delone sets with finite local complexity. We characterize validity of a subadditive ergodic theorem by uniform positivity of certain weights. The latter can be considered to be an averaged version of linear repetitivity. In this…

Combinatorics · Mathematics 2012-02-28 Adnene Besbes , Michael Boshernitzan , Daniel Lenz

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…

Algebraic Geometry · Mathematics 2024-04-10 Rocco Chirivì , Xin Fang , Peter Littelmann

A basic question for any property of quasi--coherent sheaves on a scheme $X$ is whether the property is local, that is, it can be defined using any open affine covering of $X$. Locality follows from the descent of the corresponding module…

Commutative Algebra · Mathematics 2011-10-26 Sergio Estrada , Pedro A. Guil Asensio , Jan Trlifaj

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…

Algebraic Geometry · Mathematics 2023-03-24 Mihai Fulger , Nabanita Ray

We study the $(k,s)$-positivity for holomorphic vector bundles on compact complex manifolds. $(0,s)$-positivity is exactly the Demailly $s$-positivity and a $(k,1)$-positive line bundle is just a $k$-positive line bundle in the sense of…

Algebraic Geometry · Mathematics 2010-07-13 Qi-Lin Yang

Proven by A. Parshin and S. Arakelov in the early 70's, Shafaverich hyperbolicity conjecture states that a family of curves of genus $g\ge2$ parametrized by a non hyperbolic curve (\emph{i.e.} isomorphic to $\mathbb{P}^1$, $\mathbb{C}$,…

Algebraic Geometry · Mathematics 2016-04-01 Benoît Claudon

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…

Algebraic Geometry · Mathematics 2024-07-01 Concettina Galati , Andreas Leopold Knutsen

We prove the Demailly--Peternell--Schneider conjecture in positive characteristic: if $X$ is a smooth projective variety over an algebraically closed field of characteristic $p>0$ with $-K_X$ is nef, then the Albanese morphism $a: X \to A$…

Algebraic Geometry · Mathematics 2023-05-04 Sho Ejiri , Zsolt Patakfalvi

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

Algebraic Geometry · Mathematics 2019-05-09 Aeran Fleming

We survey results concerning behavior of positivity of line bundles and possible vanishing theorems in positive characteristic. We also try to describe variation of positivity in mixed characteristic. These problems are very much related to…

Algebraic Geometry · Mathematics 2015-03-24 Adrian Langer

Our main goal in this article is to establish a quantitative version of the positivity properties of twisted relative pluricanonical bundles and their direct images. The notion of "singular Hermitian metric" on vector bundles (together with…

Algebraic Geometry · Mathematics 2014-09-22 Mihai Păun , Shigeharu Takayama

In the present sequel to our previous two papers on regularity on abelian varieties, we give a number of new applications of the theory of $M$-regularity to the study of Seshadri constants, Picard bundles, pluricanonical maps on irregular…

Algebraic Geometry · Mathematics 2007-05-23 Giuseppe Pareschi , Mihnea Popa

Observations have shown that a model with a positive cosmological constant is more appropriate to describe our universe. The aim of this manuscript is to study the gravitational fields in de Sitter space-time. To achieve this goal, de…

General Relativity and Quantum Cosmology · Physics 2022-04-13 Djeyrane-Sophie Erfani

We explore Seshadri constants associated to weighted blow-ups of complex projective varieties and demonstrate how to use this notion to construct symplectic embeddings of ellipsoids. We illustrate the utility of this point of view by…

Symplectic Geometry · Mathematics 2026-05-28 Jonathan David Evans

We study locally constant coefficients. We first study the theory of homotopy Kan extensions with locally constant coefficients in model categories, and explain how it characterizes the homotopy theory of small categories. We explain how to…

Algebraic Topology · Mathematics 2009-12-12 Denis-Charles Cisinski

We generalize Demailly's construction of projective jet bundles and strictly negatively curved pseudometrics on them to the logarithmic case. We establish this logarithmic generalization explicitly via coordinates, just as Noguchi's…

Algebraic Geometry · Mathematics 2014-12-01 Gerd-Eberhard Dethloff , Steven Shin-Yi Lu

The existence of a Seshadri stratification on an embedded projective variety provides a flat degeneration of the variety to a union of projective toric varieties, called a semi-toric variety. Such a stratification is said to be normal when…

Algebraic Geometry · Mathematics 2025-09-03 Rocco Chirivì , Xin Fang , Peter Littelmann

An introduction into the theory of locally anisotropic spaces (modelled as vector bundles provided with compatible nonlinear and distinguished linear connections and metric structures and containing as particular cases different types of…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Sergiu I. Vacaru

We formulate and prove a {\it Local Stable Manifold Theorem\/} for stochastic differential equations (sde's) that are driven by spatial Kunita-type semimartingales with stationary ergodic increments. Both Stratonovich and It\^o-type…

Probability · Mathematics 2016-09-07 Salah-Eldin A. Mohammed , Michael K. R. Scheutzow

By use of a natural map introduced recently by the first and third authors from the space of pure-type complex differential forms on a complex manifold to the corresponding one on the small differentiable deformation of this manifold, we…

Complex Variables · Mathematics 2021-04-28 Sheng Rao , Xueyuan Wan , Quanting Zhao