English
Related papers

Related papers: Nilpotent coadjoint orbits in small characteristic

200 papers

In this paper, we construct and classify the special unipotent representations of a real reductive group attached to the principal nilpotent orbit. We give formulas for the $\mathbf{K}$-types, associated varieties, and Langlands parameters…

Representation Theory · Mathematics 2020-09-25 Lucas Mason-Brown

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

For the Lie algebra $\g$ of a connected infinite-dimensional Lie group~$G$, there is a natural duality between so-called semi-equicontinuous weak-*-closed convex Ad^*(G)-invariant subsets of the dual space $\g'$ and Ad(G)-invariant lower…

Representation Theory · Mathematics 2019-11-07 Karl-Hermann Neeb

We prove the existence of a model companion of the two-sorted theory of $c$-nilpotent Lie algebras over a field satisfying a given theory of fields. We describe a language in which it admits relative quantifier elimination up to the field…

Logic · Mathematics 2025-07-18 Christian d'Elbée , Isabel Müller , Nicholas Ramsey , Daoud Siniora

We prove that a locally nilpotent group $G$ of $C^{1}$ diffeomorphisms of a compact surface $S$ of non-vanishing Euler characteristic has a finite orbit ${\mathcal O}$ whose cardinal is bounded by above by a function of the characteristic…

Dynamical Systems · Mathematics 2021-04-02 Javier Ribón

The irreducible representations of complex semisimple algebraic groups with finitely many orbits are parametrized by graded simple Lie algebras. For the exceptional Lie algebras, Kraskiewicz and Weyman exhibit the Hilbert polynomials and…

Representation Theory · Mathematics 2017-09-19 Federico Galetto

Let $\0$ be a nilpotent orbit in a semisimple complex Lie algebra $\g$. Denote by $G$ the simply connected Lie group with Lie algebra $\g$. For a $G$-homogeneous covering $M \to \0$, let $X$ be the normalization of $\bar{\0}$ in the…

Algebraic Geometry · Mathematics 2007-05-23 Baohua Fu

Some nilpotent Lie groups possess a transformation group analogous to the similarity group acting on the Euclidean space. We call such a pair a nilpotent similarity structure. It is notably the case for all Carnot groups and their…

Differential Geometry · Mathematics 2020-03-09 Raphaël Alexandre

Let $(N,L)$ be a pair of finite dimensional nilpotent Lie algebras and $N$ admits a complement $K$ in $L$ such that $\dim N=n$ and $\dim K=m$. Let $s(N,L)=\frac{1}{2}(n-1)(n-2)+1+(n-1)m-\dim \M(N,L)$, where $\M(N,L)$ denotes the multiplier…

Rings and Algebras · Mathematics 2022-08-17 Mostafa Sajedi , Mohammad Reza R. Moghaddam

We use the theory of finite W-algebras associated to nilpotent orbits in the Lie algebra g = gl_N(C) to give another proof of Moeglin's theorem about completely prime primitive ideals in the enveloping algebra U(g). We also make some new…

Representation Theory · Mathematics 2019-02-20 Jonathan Brundan

We study the geometrical structure of the coadjoint orbits of an arbitrary complex or real Lie algebra ${\mathfrak g}$ containing some ideal ${\mathfrak n}$. It is shown that any coadjoint orbit in ${\mathfrak g}^*$ is a bundle with the…

Differential Geometry · Mathematics 2010-07-16 Ihor Mykytyuk

We prove that for any two projective symplectic resolutions $Z_1$ and $Z_2$ for a nilpotent orbit closure in a complex simple Lie algebra of classical type, then $Z_1$ is deformation equivalen to $Z_2$.

Algebraic Geometry · Mathematics 2007-05-23 Baohua Fu

We extend results on finite dimensional nilpotent Lie algebras to Leibniz algebras and counterexamples to others are found. One generator algebras are used in these examples and are investigated further.

Rings and Algebras · Mathematics 2012-07-17 Chelsie Batten Ray , Alexander Combs , Nicole Gin , Allison Hedges , J. T. Hird , Laurie Zack

For the classical groups, Kraft and Procesi have resolved the question of which nilpotent orbits have closures which are normal and which are not, with the exception of the very even orbits in $D_{2l}$ which have partition of the form…

Representation Theory · Mathematics 2007-05-23 Eric Sommers

We develop an algorithm for computing the closure of a given nilpotent $G_0$-orbit in $\g_1$, where $\g_1$ and $G_0$ are coming from a $\Z$ or a $\Z/m\Z$-grading $\g= \bigoplus \g_i$ of a simple complex Lie algebra $\g$.

Algebraic Geometry · Mathematics 2015-03-19 W. A. de Graaf , E. B. Vinberg , O. S. Yakimova

A Lie algebra $L$ is said to be of breadth $k$ if the maximal dimension of the images of left multiplication by elements of the algebra is $k$. In this paper we give characterization of finite dimensional nilpotent Lie algebras of breadth…

Rings and Algebras · Mathematics 2014-10-13 Borworn Khuhirun , Kailash C. Misra , Ernie Stitzinger

The orbital varieties are the irreducible components of the intersection between a nilpotent orbit and a Borel subalgebra of the Lie algebra of a reductive group. There is a geometric correspondence between orbital varieties and irreducible…

Representation Theory · Mathematics 2018-10-31 Lucas Fresse , Anna Melnikov

Let G be a connected reductive group defined over a non-archimedean local field of characteristic 0. We assume G is quasi-split, adjoint and absolutly simple. Let g be the Lie algebra of G. We consider the space of the invariant…

Representation Theory · Mathematics 2025-09-15 Jean-Loup Waldspurger

We continue the study of the closures of $GL(V)$-orbits in the enhanced nilpotent cone $V\times\cN$ begun by the first two authors. We prove that each closure is an invariant-theoretic quotient of a suitably-defined enhanced quiver variety.…

Representation Theory · Mathematics 2011-08-26 Pramod N. Achar , Anthony Henderson , Benjamin F. Jones

In this paper, we begin a quantization program for nilpotent orbits of a real semisimple Lie group. These orbits and their covers generalize the symplectic vector space. A complex structure polarizing the orbit and invariant under a maximal…

Symplectic Geometry · Mathematics 2016-09-07 Ranee Brylinski