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Related papers: Mixed Commuting Varieties over simple Lie algebras

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Let U be the unipotent radical of a Borel subgroup of a connected reductive algebraic group G, which is defined over an algebraically closed field k. In this paper, we extend work by Goodwin-R\"ohrle concerning the commuting variety of…

Representation Theory · Mathematics 2019-04-10 Rolf Farnsteiner

The aim of this paper is to describe the irregular locus of the commuting variety of a reductive symmetric Lie algebra. More precisely, we want to enlighten a remark of Popov. In [Po], the irregular locus of the commuting variety of any…

Representation Theory · Mathematics 2010-09-06 Bulois Michael

The nilpotent cone of a reductive Lie algebra has a desingularization given by thecotangent bundle of the flag variety. Analogously, the nullcone of a cartesianpower of the algebra has a desingularization given by a vector bundle over…

Representation Theory · Mathematics 2016-04-25 Jean-Yves Charbonnel , Mouchira Zaiter

The commuting variety of a reductive Lie algebra $\mathfrak{g}$ is the underlying variety of a well defined subscheme of $\mathfrak{g}\times\mathfrak{g}$. In this note, it is proved that this scheme is normal and Cohen-Macaulay. In…

Algebraic Geometry · Mathematics 2025-04-22 Jean-Yves Charbonnel

Let $G$ be an algebraic group and let $X$ be a smooth $G$-variety with two orbits: an open orbit and a a closed orbit of codimension $1$. We give an algebraic description of the category of $G$-equivariant vector bundles on $X$ under a mild…

Algebraic Geometry · Mathematics 2022-02-22 Lucas Mason-Brown , James Tao

Here we prove that a commuting variety associated with a symmetric pair (g, g_0) is irreducible for (so_{n+m}, so_n + so_m) and reducible for (gl_{n+m}, {gl}_n + gl_m) with n>m, (so_{2n}, gl_n) with odd n, (E_6, {so}_{10} + k).

Representation Theory · Mathematics 2007-05-23 Oksana Yakimova

For any module $M$ over small quantum group one defines the support variety using construction from the theory of restricted Lie algebras. It is a closed conical subset of nilpotent cone of the corresponding Lie algebra. If module $M$ is a…

q-alg · Mathematics 2007-05-23 V. Ostrik

Let $G$ be a simply-connected semisimple algebraic group over an algebraically closed field of characteristic $p$, assumed to be larger than the Coxeter number. The "support variety" of a $G$-module $M$ is a certain closed subvariety of the…

Representation Theory · Mathematics 2018-03-28 Pramod N. Achar , William Hardesty , Simon Riche

Let $\N_n$ be the set of nilpotent $n$ by $n$ matrices over an algebraically closed field $k$. For each $r\ge 2$, let $C_r(\N_n)$ be the variety consisting of all pairwise commuting $r$-tuples of nilpotent matrices. It is well-kown that…

Representation Theory · Mathematics 2013-08-13 Robert M. Guralnick , Nham V. Ngo

For a reductive Lie algbera over an algbraically closed field of charasteristic zero,we consider a borel subgroup $B$ of its adjoint group, a Cartan subalgebra contained inthe Lie algebra of $B$ and the closure $X$ of its orbit under $B$ in…

Representation Theory · Mathematics 2016-08-08 Jean-Yves Charbonnel

We prove that the nilpotent commuting variety of a reductive Lie algebra over an algebraically closed field of good characteristic is equidimensional. In characteristic zero, this confirms a conjecture of Vladimir Baranovsky. As a…

Representation Theory · Mathematics 2015-06-26 Alexander Premet

Let g be a semisimple Lie algebra of finite dimension. The nullcone N of g is the set of (x,y) in g x g such that x and y are nilpotents and are in the same Borel sualgebra. The main result of this paper is that N is a closed and…

Representation Theory · Mathematics 2011-06-06 Mouchira Zaiter

This is a continuation of our work to understand vertex operator algebras using the geometric properties of varieties attached to vertex operator algebras. For a class of vertex operator algebras including affine vertex operator algebras…

Representation Theory · Mathematics 2017-09-19 Yanjun Chu , Zongzhu Lin

We initiate the investigation of the projective variety $E(r,g)$ of elementary subalgebras of dimension $r$ of a ($p$-restricted) Lie algebra $g$ for some $r > 0$ and demonstrate that this variety encodes considerable information about the…

Rings and Algebras · Mathematics 2014-09-25 Jon F. Carlson , Eric M. Friedlander , Julia Pevtsova

We study certain "\sigma-commuting varieties" associated with a pair of commuting involutions of a semisimple Lie algebra $\g$. The usual commuting variety of $\g$ and commuting varieties related to one involution are particular cases of…

Algebraic Geometry · Mathematics 2016-01-20 Dmitri I. Panyushev

Let F be the flag variety of a complex semi-simple group G, let H be an algebraic subgroup of G acting on F with finitely many orbits, and let V be an H-orbit closure in F. Expanding the cohomology class of V in the basis of Schubert…

Algebraic Geometry · Mathematics 2007-05-23 Michel Brion

Let $G$ be connected reductive algebraic group defined over an algebraically closed field of characteristic $p > 0$ and suppose that $p$ is a good prime for the root system of $G$, the derived subgroup of $G$ is simply connected and the Lie…

Representation Theory · Mathematics 2021-08-13 Alexander Premet , Lewis Topley

Let $V$ be a simple vertex operator algebra which admits the continuous, faithful action of a compact Lie group $G$ of automorphisms. We establish a Schur-Weyl type duality between the unitary, irreducible modules for $G$ and the…

q-alg · Mathematics 2008-02-03 Chongying Dong , Haisheng Li , Geoffrey Mason

We explore a relationship between the classical representation theory of a complex, semisimple Lie algebra \g and the resonance varieties R(V,K)\subset V^* attached to irreducible \g-modules V and submodules K\subset V\wedge V. In the…

Representation Theory · Mathematics 2016-11-17 Stefan Papadima , Alexander I. Suciu

The motivation for this paper is to detect when an irreducible projective variety V is not toric. We do this by analyzing a Lie group and a Lie algebra associated to V. If the dimension of V is strictly less than the dimension of the above…

Algebraic Geometry · Mathematics 2025-12-17 Aida Maraj , Arpan Pal