English
Related papers

Related papers: Fano varieties with finitely generated semigroups …

200 papers

We show that the Okounkov body of a big divisor with finitely generated section ring is a rational simplex, for an appropriate choice of flag; furthermore, when the ambient variety is a surface, the same holds for every big divisor. Under…

Algebraic Geometry · Mathematics 2015-06-10 Dave Anderson , Alex Küronya , Victor Lozovanu

Let \Delta be the Okounkov body of a divisor D on a projective variety X. We describe a geometric criterion for \Delta to be a lattice polytope, and show that in this situation X admits a flat degeneration to the corresponding toric…

Algebraic Geometry · Mathematics 2014-02-18 Dave Anderson

Anderson proved that the finite generation of the value semigroup $\Gamma_{Y_\bullet}(D)$ in the construction of the Newton-Okounkov body $\Delta_{Y_\bullet}(D)$ induces a toric degeneration of the corresponding variety $X$ to some toric…

Algebraic Geometry · Mathematics 2018-01-15 Georg Merz

Based on the work of Okounkov (\cite{Ok96}, \cite{Ok03}), Lazarsfeld and Musta\c t\u a (\cite{LM08}) and Kaveh and Khovanskii (\cite{KK08}) have independently associated a convex body, called the Okounkov body, to a big divisor on a smooth…

Algebraic Geometry · Mathematics 2010-08-27 Alex Kuronya , Victor Lozovanu , Catriona Maclean

An Okounkov body is a convex subset in Euclidean space associated to a big divisor on a smooth projective variety with respect to an admissible flag. In this paper, we introduce two convex bodies associated to pseudoeffective divisors,…

Algebraic Geometry · Mathematics 2018-02-06 Sung Rak Choi , Yoonsuk Hyun , Jinhyung Park , Joonyeong Won

Let $X_\mathcal{A}$ be the projective toric variety corresponding to a finite set of lattice points $\mathcal{A}$. We show that irreducible components of the Fano scheme $\mathbf{F}_k(X_\mathcal{A})$ parametrizing $k$-dimensional linear…

Algebraic Geometry · Mathematics 2019-11-26 Nathan Ilten , Alexandre Zotine

Let $X$ be a projective irreducible holomorphic symplectic manifold. We associate with any big $\mathbf{R}$-divisor $D$ on $X$ a convex polygon $\Delta_E^{\mathrm{num}}(D)$ of dimension 2, whose Euclidean volume is…

Algebraic Geometry · Mathematics 2025-01-22 Francesco Antonio Denisi

We prove that for smooth projective toric varieties, the Okounkov body of a $T$-invariant pseudo-effective divisor with respect to a $T$-invariant flag decomposes as a finite Minkowski sum of indecomposable polytopes. We prove that these…

Algebraic Geometry · Mathematics 2016-01-20 Piotr Pokora , David Schmitz , Stefano Urbinati

A Newton-Okounkov body is a convex body constructed from a projective variety with a globally generated line bundle and with a higher rank valuation on the function field, which gives a systematic method of constructing toric degenerations…

Representation Theory · Mathematics 2025-07-24 Naoki Fujita , Akihiro Higashitani

We prove that the existence of a finite Minkowski base for Okounkov bodies on a smooth projective variety with respect to an admissible flag implies rational polyhedrality of the global Okounkov body. As an application of this general…

Algebraic Geometry · Mathematics 2014-03-19 David Schmitz , Henrik Seppänen

For an arbitrary smooth n-dimensional Fano variety $X$ we introduce the notion of a small toric degeneration. Using small toric degenerations of Fano n-folds $X$, we propose a general method for constructing mirrors of Calabi-Yau complete…

alg-geom · Mathematics 2007-05-23 Victor V. Batyrev

The global Okounkov body of a projective variety is a closed convex cone that encodes asymptotic information about every big line bundle on the variety. In the case of a rank two toric vector bundle E on a smooth projective toric variety,…

Algebraic Geometry · Mathematics 2011-01-04 José Luis González

A $n$-dimensional Gorenstein toric Fano variety $X$ is called Del Pezzo variety if the anticanonical class $-K_X$ is a $(n-1)$-multiple of a Cartier divisor. Our purpose is to give a complete biregular classfication of Gorenstein toric Del…

Algebraic Geometry · Mathematics 2009-04-14 Victor Batyrev , Dorothee Juny

We prove that the Okounkov body of a big divisor with respect to a general flag on a smooth projective surface whose pseudo-effective cone is rational polyhedral decomposes as the Minkowski sum of finitely many simplices and line segments…

Algebraic Geometry · Mathematics 2016-08-11 Patrycja Łuszcz-Świdecka , David Schmitz

The Newton--Okounkov body of a big divisor D on a smooth surface is a numerical invariant in the form of a convex polygon. We study the geometric significance of the shape of Newton--Okounkov polygons of ample divisors, showing that they…

Algebraic Geometry · Mathematics 2022-03-16 Joaquim Roé , Tomasz Szemberg

Let X be a smooth complex projective variety of dimension n equipped with a very ample Hermitian line bundle L. In the first part of the paper, we show that if there exists a toric degeneration of X satisfying some natural hypotheses (which…

Algebraic Geometry · Mathematics 2015-04-10 Megumi Harada , Kiumars Kaveh

Generalizing the notion of Newton polytope, we define the Newton-Okounkov body, respectively, for semigroups of integral points, graded algebras, and linear series on varieties. We prove that any semigroup in the lattice Z^n is…

Algebraic Geometry · Mathematics 2012-03-30 Kiumars Kaveh , A. G. Khovanskii

We first prove some basic properties of Okounkov bodies, and give a characterization of Nakayama and positive volume subvarieties of a pseudoeffective divisor in terms of Okounkov bodies. Next, we show that each valuative and limiting…

Algebraic Geometry · Mathematics 2017-04-25 Sung Rak Choi , Jinhyung Park , Joonyeong Won

In this paper we present a new kind of semigroups called convex body semigroups which are generated by convex bodies of R^k. They generalize to arbitrary dimension the concept of proportionally modular numerical semigroup of [7]. Several…

Commutative Algebra · Mathematics 2013-10-15 J. I. García-García , M. A. Moreno-Frías , A. Sánchez-R. -Navarro , A. Vigneron-Tenorio

We define and study the global Okounkov moment cone of a projective spherical variety X, generalizing both the global Okounkov body and the moment body of X defined by Kaveh and Khovanskii. Under mild assumptions on X we show that the…

Algebraic Geometry · Mathematics 2017-10-02 Guido Pezzini , Henrik Seppänen
‹ Prev 1 2 3 10 Next ›