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Related papers: Global Okounkov bodies for Bott-Samelson varieties

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A theorem of Ryan and Wolper states that a type A Schubert variety is smooth if and only if it is an iterated fibre bundle of Grassmannians. We extend this theorem to arbitrary finite type, showing that a Schubert variety in a generalized…

Algebraic Geometry · Mathematics 2017-02-10 Edward Richmond , William Slofstra

We initiate a combinatorial study of Newton-Okounkov functions on toric varieties with an eye on the rationality of asymptotic invariants of line bundles. In the course of our efforts we identify a combinatorial condition which ensures a…

Algebraic Geometry · Mathematics 2021-01-20 Christian Haase , Alex Küronya , Lena Walter

We associate to a filtration of a graded linear series of a big line bundle a concave function on the Okounkov body whose law with respect to Lebesgue's measure describes the asymptotic distribution of the jumps of the filtration. As a…

Algebraic Geometry · Mathematics 2019-02-20 Sebastien Boucksom , Huayi Chen

Let $X$ be a smooth irreducible complex algebraic variety of dimension $n$ and $L$ a very ample line bundle on $X$. Given a toric degeneration of $(X,L)$ satisfying some natural technical hypotheses, we construct a deformation $\{J_s\}$ of…

Symplectic Geometry · Mathematics 2018-03-02 Mark Hamilton , Megumi Harada , Kiumars Kaveh

Given an orbifold, we construct an orthogonal spectrum representing its stable global homotopy type. Orthogonal spectra now represent orbifold cohomology theories which automatically satisfy certain properties as additivity and the…

Algebraic Topology · Mathematics 2025-12-24 Branko Juran

We demonstrate how pipe dreams can be applied to the theory of poset polytopes to produce toric degenerations of flag varieties. Specifically, we present such constructions for marked chain-order polytopes of Dynkin types A and C. These…

Algebraic Geometry · Mathematics 2024-03-18 Ievgen Makedonskyi , Igor Makhlin

In this paper, we study the geometry of various Hessenberg varieties in type A, as well as families thereof, with the additional goal of laying the groundwork for future computations of Newton-Okounkov bodies of Hessenberg varieties. Our…

Algebraic Geometry · Mathematics 2021-02-04 Hiraku Abe , Lauren DeDieu , Federico Galetto , Megumi Harada

Let G be a semisimple complex Lie group. In this article, we study Geometric Invariant Theory on a flag variety G/B with respect to the action of a principal 3-dimensional simple subgroup S of G. We determine explicitly the GIT-equivalence…

Representation Theory · Mathematics 2015-11-10 Henrik Seppänen , Valdemar V. Tsanov

Let $\Mg$ denote the moduli space of compact Riemann surfaces of genus $g$. Mumford had proved that, for each fixed genus $g$, there are isomorphisms asserting that certain higher $DET$ bundles over $\Mg$ are certain fixed…

alg-geom · Mathematics 2008-02-03 Indranil Biswas , Subhashis Nag , Dennis Sullivan

We continue to explore the numerical nature of the Okounkov bodies focusing on the local behaviors near given points. More precisely, we show that the set of Okounkov bodies of a pseudoeffective divisor with respect to admissible flags…

Algebraic Geometry · Mathematics 2020-08-10 Sung Rak Choi , Jinhyung Park , Joonyeong Won

We give a new construction of the Bott-Samelson variety $Z$ as the closure of a $B$-orbit in a product of flag varieties $(G/B)^l$. This also gives an embedding of the projective coordinate ring of the variety into the function ring of a…

alg-geom · Mathematics 2008-02-03 Peter M. Magyar

Let $G$ be a complex simple Lie group, and let $U \subseteq G$ be a maximal compact subgroup. Assume that $G$ admits a homogenous space $X=G/Q=U/K$ which is a compact Hermitian symmetric space. Let $\mathscr{L} \rightarrow X$ be the ample…

Representation Theory · Mathematics 2011-10-31 Benjamin Schwarz , Henrik Seppänen

In his work on log-concavity of multiplicities, Okounkov showed in passing that one could associate a convex body to a linear series on a projective variety, and then use convex geometry to study such linear systems. Although Okounkov was…

Algebraic Geometry · Mathematics 2008-05-30 Robert Lazarsfeld , Mircea Mustata

We construct positive-genus analogues of Welschinger's invariants for many real symplectic manifolds, including the odd-dimensional projective spaces and the renowned quintic threefold. In some cases, our invariants provide lower bounds for…

Symplectic Geometry · Mathematics 2018-02-27 Penka Georgieva , Aleksey Zinger

We formulate a tropical analogue of Grothendieck's section conjecture: that for every stable graph G of genus g>2, and every field k, the generic curve with reduction type G over k satisfies the section conjecture. We prove many cases of…

Algebraic Geometry · Mathematics 2023-06-01 Wanlin Li , Daniel Litt , Nick Salter , Padmavathi Srinivasan

In this paper we explore the connection between asymptotic base loci and Newton-Okounkov bodies associated to infinitesimal flags. Analogously to the surface case, we obtain complete characterizations of augmented and restricted base loci.…

Algebraic Geometry · Mathematics 2015-07-16 Alex Küronya , Victor Lozovanu

For classical groups SL(n), SO(n) and Sp(2n), we define uniformly geometric valuations on the corresponding complete flag varieties. The valuation in every type comes from a natural coordinate system on the open Schubert cell and is…

Algebraic Geometry · Mathematics 2019-02-08 Valentina Kiritchenko

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

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

The theory of Newton-Okounkov polytopes is a generalization of that of Newton polytopes for toric varieties, and it gives a systematic method of constructing toric degenerations of a projective variety. In the case of Schubert varieties,…

Algebraic Geometry · Mathematics 2017-03-10 Naoki Fujita