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Related papers: Flexibility of Schubert classes

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We give an explicit combinatorial description of the multiplicity as well as the Hilbert function of the tangent cone at any point on a Schubert variety in the symplectic Grassmannian.

Representation Theory · Mathematics 2011-02-10 Sudhir R. Ghorpade , K. N. Raghavan

We show that many important varieties and sets of varieties of semigroups may be defined by relatively simple and transparent first-order formulas in the lattice of all semigroup varieties.

Group Theory · Mathematics 2010-09-08 B. M. Vernikov

An algebraic variety $X$ is called a homogeneous variety if the automorphism group $\mathrm{Aut}(X)$ acts on $X$ transitively, and a homogeneous space if there exists a transitive action of an algebraic group on $X$. We prove a criterion of…

Algebraic Geometry · Mathematics 2024-03-26 Ivan Arzhantsev , Yulia Zaitseva

We describe an algorithm which pattern embeds, in the sense of Woo-Yong, any Bruhat interval of a symmetric group into an interval whose extremes lie in the same right Kazhdan-Lusztig cell. This apparently harmless fact has applications in…

Representation Theory · Mathematics 2021-07-20 Martina Lanini , Peter J. McNamara

We introduce the notion of a contractible subshift. This is a strengthening of the notion of strong irreducibility, where we require that the gluings are given by a block map. We show that a subshift is a retract of a full shift if and only…

Dynamical Systems · Mathematics 2026-04-24 Leo Poirier , Ville Salo

We discuss two possible ways of representing tolerances: first, as a homomorphic image of some congruence; second, as the relational composition of some compatible relation with its converse. The second way is independent from the variety…

Rings and Algebras · Mathematics 2016-04-19 Paolo Lipparini

We give explicit formulas on total Springer representations for classical types. We also describe the characters of restrictions of such representations to a maximal parabolic subgroup isomorphic to a symmetric group. As a result, we give…

Representation Theory · Mathematics 2018-05-29 Dongkwan Kim

Let X and Y be nonsingular real algebraic varieties, dimX>dimY-1. Assume that the variety Y is malleable, compact and connected. Our main result implies that each regular map from X to Y is homotopic to a surjective regular map. The class…

Algebraic Geometry · Mathematics 2023-02-07 Wojciech Kucharz

The following conjecture on the deformation invariance of plurigenera is proved. For a smooth projective holomorphic family of compact complex manifolds over the open unit 1-disk such that all the fibers are of general type, every…

alg-geom · Mathematics 2009-10-30 Yum-Tong Siu

A multiplication on persistence diagrams is introduced by means of Schubert calculus. The key observation behind this multiplication comes from the fact that the representation space of persistence modules has the structure of the Schubert…

Algebraic Topology · Mathematics 2024-09-23 Yasuaki Hiraoka , Kohei Yahiro , Chenguang Xu

In this paper we describe the relationship between the finite free resolutions of perfect ideals in split format (for Dynkin formats) and certain intersections of opposite Schubert varieties with the big cell for homogeneous spaces $G/P$…

Commutative Algebra · Mathematics 2021-04-20 Steven V Sam , Jerzy Weyman

We prove that it is decidable if a finitely based permutation class contains infinitely many simple permutations, and establish an unavoidable substructure result for simple permutations: every sufficiently long simple permutation contains…

Combinatorics · Mathematics 2007-05-23 Robert Brignall , Nik Ruskuc , Vince Vatter

Let $X$ be a complex nonsingular variety with globally generated tangent bundle. We prove that the signed Segre-MacPherson (SM) class of a constructible function on $X$ with effective characteristic cycle is effective. This observation has…

Algebraic Geometry · Mathematics 2025-04-02 Paolo Aluffi , Leonardo C. Mihalcea , Jörg Schürmann , Changjian Su

In this work we study characteristic classes of possibly singular varieties embedded as a closed subvariety of a nonsingular variety. In special, we express the Schwartz-MacPherson class in terms of the $\mu$-class and Chern class of the…

Algebraic Geometry · Mathematics 2024-10-04 Antonio M. Ferreira , Fernando Lourenco

Recent results by Abert, Bergeron, Biringer et al., Finis, Lapid and Mueller, and Shin and Templier have extended the limit multiplicity property to quite general classes of groups and sequences of level subgroups. Automorphic…

Number Theory · Mathematics 2016-01-28 John Binder

We study varieties of complexes of projective modules with fixed ranks, and relate these varieties to the varieties of their homologies. We show that for an algebra of global dimension at most two, these two varieties are related by a pair…

Representation Theory · Mathematics 2014-10-02 Darmajid , Bernt Tore Jensen

We provide a partial result on Taylor's modularity conjecture, and several related problems. Namely, we show that the interpretability join of two idempotent varieties that are not congruence modular is not congruence modular either, and we…

Rings and Algebras · Mathematics 2018-12-06 Jakub Opršal

The study of irreducible subvarieties has recently seen a surge of interest due to connections with convex geometry. In this paper, we study cohomology classes of Grassmannians that are realizable by irreducible subvarieties. We completely…

Algebraic Geometry · Mathematics 2025-09-05 Izzet Coskun , Julius Ross

I describe the monodromy of smooth hypersurfaces $X$ of high degree in a fixed smooth variety $Y$ containing a fixed subvariety $W$ of $Y$. The cohomology of $X$ in middle degree spanned by the pull-back of the cohomology of $Y$ and by the…

Algebraic Geometry · Mathematics 2007-05-23 Ania Otwinowska

To every finite-dimensional $\mathbb C$-algebra $\Lambda$ of finite representation type we associate an affine variety. These varieties are a large generalization of the varieties defined by "$u$ variables" satisfying "$u$-equations", first…

Representation Theory · Mathematics 2026-01-01 Nima Arkani-Hamed , Hadleigh Frost , Pierre-Guy Plamondon , Giulio Salvatori , Hugh Thomas