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Related papers: Quiver Grassmannians and degenerate flag varieties

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This paper introduces a class of smooth projective varieties that generalise and share many properties with partial flag varieties of type A. The quiver flag variety M_\vartheta(Q,r) of a finite acyclic quiver Q (with a unique source) and a…

Algebraic Geometry · Mathematics 2019-12-19 Alastair Craw

We define linear degenerations of Schubert varieties via a special class of quiver Grassmannians. To do so, we restrict our study to an appropriate subvariety in the variety of representations of the considered quiver and describe a base…

Representation Theory · Mathematics 2026-02-17 Giulia Iezzi

We construct Nakajima's quiver varieties of type A in terms of conjugacy classes of matrices and (non-Slodowy's) transverse slices naturally arising from affine Grassmannians. In full generality quiver varieties are embedded into…

Algebraic Geometry · Mathematics 2008-12-31 Ivan Mirković , Maxim Vybornov

Degenerations of linear series on smooth projective varieties approaching multicomponent varieties $X$ give rise to certain quiver representations in the category of linear series over $X$, which yield rational maps from $X$ to the…

Algebraic Geometry · Mathematics 2025-07-02 Eduardo Esteves , Piere Rodriguez , Eduardo Vital

Reineke and independent other authors proved that every projective variety arises as a quiver Grassmannian. We prove the claim in the title by restricting Reineke's isomorphism to Grassmannians for a fully exact subcategory.

Representation Theory · Mathematics 2024-12-19 Alexander Pütz , Julia Sauter

We give a local characterization for when certain quiver representations in semisimple Abelian categories are semisimple, among them those arising from degenerations of linear series. This paper is the first of two, aimed to describe all…

Algebraic Geometry · Mathematics 2025-12-30 Eduardo Esteves , Renan Santos , Eduardo Vital

Let k be an algebraically closed field and A a finite-dimensional k-algebra. Given an A-module M, the set G_e(M) of all submodules of M with dimension vector e is called a quiver Grassmannian. If D,Y are A-modules, then we consider Hom(D,Y)…

Representation Theory · Mathematics 2013-05-21 Claus Michael Ringel

We study geometric and combinatorial properties of the degenerate flag varieties of type A. These varieties are acted upon by the automorphism group of a certain representation of a type A quiver, containing a maximal torus T. Using the…

Algebraic Geometry · Mathematics 2012-11-16 Giovanni Cerulli Irelli , Evgeny Feigin , Markus Reineke

In this paper, we introduce Schubert decompositions for quiver Grassmannians and investigate example classes of quiver Grassmannians with a Schubert decomposition into affine spaces. The main theorem puts the cells of a Schubert…

Algebraic Geometry · Mathematics 2013-03-29 Oliver Lorscheid

We define and investigate algebraic torus actions on quiver Grassmannians for nilpotent representations of the equioriented cycle. Examples of such varieties are type $\tt A$ flag varieties, their linear degenerations, finite dimensional…

Representation Theory · Mathematics 2023-01-03 Martina Lanini , Alexander Pütz

A quiver representation assigns a vector space to each vertex, and a linear map to each arrow. When one considers the category $\textrm{Vect}(\mathbb{F}_1)$ of vector spaces ``over $\mathbb{F}_1$'' (the field with one element), one obtains…

Representation Theory · Mathematics 2023-12-15 Jaiung Jun , Alex Sistko

We continue, generalize and expand our study of linear degenerations of flag varieties from [G. Cerulli Irelli, X. Fang, E. Feigin, G. Fourier, M. Reineke, Math. Z. 287 (2017), no. 1-2, 615-654]. We realize partial flag varieties as quiver…

Algebraic Geometry · Mathematics 2019-02-01 Giovanni Cerulli Irelli , Xin Fang , Evgeny Feigin , Ghislain Fourier , Markus Reineke

In this paper, we introduce morphisms for matroids with coefficients (in the sense of Baker and Bowler) and quiver matroids. We investigate their basic properties, such as functoriality, duality, minors and cryptomorphic characterizations…

Combinatorics · Mathematics 2026-04-14 Manoel Jarra , Oliver Lorscheid , Eduardo Vital

Several moduli spaces parametrizing linear subspaces of the projective space are cut out by linear and quadratic equations in their natural embedding: Grassmannians, Flag varieties, and Schubert varieties. The goal of this paper is to prove…

Algebraic Geometry · Mathematics 2019-04-24 Laurent Evain , Margherita Roggero

We describe all the schematic limits of families of divisors associated to a given family of rank-$r$ linear series on a one-dimensional family of projective varieties degenerating to a connected reduced projective scheme $X$ defined over…

Algebraic Geometry · Mathematics 2025-12-30 Eduardo Esteves , Renan Santos , Eduardo Vital

We study a class of Grassmannians of sub-bimodules over the path algebras of quivers. Our quiver Grassmannians include Escobar's brick manifolds as well as Labelle's generalizations. We give an explicit construction of the varieties in…

Representation Theory · Mathematics 2025-10-27 Evgeny Feigin , Markus Reineke

We present a review on the recently discovered link between the Lie theory,the theory of quiver Grassmannians, and various degenerations of flag varieties. Our starting point is the induced Poincar\'{e}--Birkhoff--Witt filtration on the…

Representation Theory · Mathematics 2022-01-13 Evgeny Feigin

Local models of Shimura varieties in type A can be realized inside products of Grassmannians via certain linear algebraic conditions. Laumon suggested a generalization which can be identified with a family over a line whose general fibers…

Algebraic Geometry · Mathematics 2023-07-06 Evgeny Feigin , Martina Lanini , Alexander Pütz

Quivers play an important role in the representation theory of algebras, with a key ingredient being the path algebra and the preprojective algebra. Quiver grassmannians are varieties of submodules of a fixed module of the path or…

Representation Theory · Mathematics 2014-05-06 Alistair Savage , Peter Tingley

We investigate quiver representations over $\mathbb{F}_1$. Coefficient quivers are combinatorial gadgets equivalent to $\mathbb{F}_1$-representations of quivers. We focus on the case when the quiver $Q$ is a pseudotree. For such quivers, we…

Representation Theory · Mathematics 2023-01-19 Jaiung Jun , Jaehoon Kim , Alex Sistko