微分算子代数的一种不可约Harish-Chandra模的分类

本文首先讨论了微分算子Ｌｉｅ代数的单性，然后确定出了微分算子Ｌｉｅ代数的权重数都是１的所有不可约Ｈａｒｉｓｈ－Ｃｈａｎｄｒａ模。     

Nonzero level Harish-Chandra modules over the Virasoro-like algebra

In the present paper, we study the nonzero level Harish-Chandra modules for the Virasoro-like algebra. We prove that a nonzero level Harish-Chandra module of the Virasoro-like algebra is a generalized highest weight (GHW for short) module. Then we prove that a GHW module of the Virasoro-like algebra is induced from an irreducible module of a Heisenberg subalgebra.     

Non-weight modules over the mirror Heisenberg-Virasoro algebra

Science China Mathematics - In this paper, we study irreducible non-weight modules over the mirror Heisenberg-Virasoro algebra $${\cal D}$$ , including Whittaker modules, $${\cal U}\left(...     

Pointed representations of Virasoro algebra

In this paper we study the pointed representations of the Virasoro algebra. We show that unitary irreducible pointed representations of the Virasoro algebra are Harish-Chandra representations, thus they either are of highest or lowest weights or have all weight spaces of dimension 1. Further, we prove that unitary irreducible weight representations of Virasoro superalgebras are either of highest weights or of lowest weights, hence they are also Harish-Chandra representations. This work was supported by CNSF     

扭的Heisenberg-Virasoro顶点算子代数的一个特征化（英文）

The twisted Heisenberg-Virasoro algebra is the universal central extension of the Lie algebra of differential operators on a circle of order at most one. In this paper, we first study the variety of semi-conformal vectors of the twisted Heisenberg-Virasoro vertex operator algebra, which is a finite set consisting of two nontrivial elements. Based on this property,we also show that the twisted Heisenberg-Virasoro vertex operator algebra is a tensor product of two vertex operator algebras. Moreover, associating to properties of semi-conformal vectors of the twisted Heisenberg-Virasoro vertex operator algebra, we charaterized twisted Heisenberg-Virasoro vertex operator algebras. This will be used to understand the classification problems of vertex operator algebras whose varieties of semi-conformal vectors are finite sets.     

Irreducible representations over the diamond Lie algebra

In this paper, we use Block’s results to classify irreducible modules over the diamond Lie algebra 𝔇. As a corollary, we also give a classification of irreducible modules over the Euclidean algebra 𝔢(2).     

REPRESENTATIONS OF THE TWO PARAMETER DEFORMATION OF THE VIRASORO ALGEBRA

This paper constructs a class of Harish-Chandra modules with multiplicity ≤1 of the two parameter deformation of Virasoro algebra and proves a classification theorem.     

Extensions of Schrödinger–Virasoro conformal modules

In this paper, we study extensions between two finite irreducible conformal modules over the Schrödinger–Virasoro conformal algebra and the extended Schrödinger–Virasoro conformal algebra. Also, we classify all finite nontrivial irreducible conformal modules over the extended Schrödinger–Virasoro conformal algebra. As a byproduct, we obtain a classification of extensions of Heisenberg–Virasoro conformal modules.     

Irreducible Harish-Chandra modules over extended Witt algebras

Let d be a positive integer, $A={\mathbb{C}} [t_{1}^{\pm1},\ldots ,t_{d}^{\pm1}]$ be the Laurent polynomial algebra, and $W=\operatorname{Der} (A)$ be the derivation Lie algebra of A. Then we have the semidirect product Lie algebra W?A which we call the extended Witt algebra of rank d. In this paper, we classify all irreducible Harish-Chandra modules over W?A with nontrivial action of A.     

Graded irreducible representations of Leavitt path algebras: A new type and complete classification

We present a new class of graded irreducible representations of a Leavitt path algebra. This class is new in the sense that its representation space is not isomorphic to any of the existing simple Chen modules. The corresponding graded simple modules complete the list of Chen modules which are graded, creating an exhaustive class: the annihilator of any graded simple module is equal to the annihilator of either a graded Chen module or a module of this new type.Our characterization of graded primitive ideals of a Leavitt path algebra in terms of the properties of the underlying graph is the main tool for proving the completeness of such classification. We also point out a problem with the characterization of primitive ideals of a Leavitt path algebra in Rangaswamy (2013) [15].     

Classification of harish-chandra modules over the super-virasoro algebras

In this paper, we first construct all indecomposable modules whose dimensions of weight spaces of the even and odd parts are ≤ 1, then classify all Harish-Chandra module over the super-Virasoro algebras, proving that every Harish-Chandra module over the super-Virasoro algebras is either a highest or lowest weight module, or else a module of the intermediate series. This result generalizes a theorem which was originally given as a conjecture by Kac on the Virasoro algebra.     

Blocks and modules for Whittaker pairs

Inspired by recent activities on Whittaker modules over various (Lie) algebras, we describe a general framework for the study of Lie algebra modules locally finite over a subalgebra. As a special case, we obtain a very general set-up for the study of Whittaker modules, which includes, in particular, Lie algebras with triangular decomposition and simple Lie algebras of Cartan type. We describe some basic properties of Whittaker modules, including a block decomposition of the category of Whittaker modules and certain properties of simple Whittaker modules under some rather mild assumptions. We establish a connection between our general set-up and the general set-up of Harish-Chandra subalgebras in the sense of Drozd, Futorny and Ovsienko. For Lie algebras with triangular decomposition, we construct a family of simple Whittaker modules (roughly depending on the choice of a pair of weights in the dual of the Cartan subalgebra), describe their annihilators, and formulate several classification conjectures. In particular, we construct some new simple Whittaker modules for the Virasoro algebra. Finally, we construct a series of simple Whittaker modules for the Lie algebra of derivations of the polynomial algebra, and consider several finite-dimensional examples, where we study the category of Whittaker modules over solvable Lie algebras and their relation to Koszul algebras.     

Irreducible highest weight representations of the simple n-Lie algebra

A. Dzhumadil??daev classified all irreducible finite dimensional representations of the simple n-Lie algebra. Using a slightly different approach, we obtain in this paper a complete classification of all irreducible, highest weight modules, including the infinite-dimensional ones. As a corollary we find all primitive ideals of the universal enveloping algebra of this simple n-Lie algebra.     

Classification of irreducible weight modules over higher rank Virasoro algebras

Let G be a rank n additive subgroup of C and Vir[G] the corresponding Virasoro algebra of rank n. In the present paper, irreducible weight modules with finite dimensional weight spaces over Vir[G] are completely determined. There are two different classes of them. One class consists of simple modules of intermediate series whose weight spaces are all 1-dimensional. The other is constructed by using intermediate series modules over a Virasoro subalgebra of rank n−1. The classification of such modules over the classical Virasoro algebra was obtained by O. Mathieu in 1992 using a completely different approach.     

Analogue Zhelobenko invariants, Bernstein–Gelfand–Gelfand operators and the Kostant Clifford algebra conjecture

Let $ \mathfrak{g} $ be a complex simple Lie algebra. The Kostant Clifford algebra conjecture can be formulated and somewhat extended as a question [7, Conj. 1.3] concerning the Harish-Chandra map for the enveloping algebra of $ \mathfrak{g} $ . In that work [7, Cor. 8.8] an analogue Kostant conjecture, obtained by replacing the Harish-Chandra map by a ??generalized Harish-Chandra?? map, was proved using a careful analysis of Zhelobenko invariants which describe the image of this map. In the present work we establish [7, Conj. 1.3] by showing that there are analogue Zhelobenko invariants which describe the image of the Harish-Chandra map. Following this a similar proof to that of [7, Cor. 8.8] goes through. In the last section a rather precise form of the Kostant Clifford algebra conjecture is established.     

广义Virasoro-Toroidal李代数不可约模

本文将Kac-Moody代数A1（1）的二阶表示理论[11]推广到Toroidal李代数的情形.并给出了A1型Toroidal李代数的一类不可约表示.     

Algebras of twisted chiral differential operators and affine localization of {\mathfrak {g}} -modules

We propose a notion of algebra of twisted chiral differential operators over algebraic manifolds with vanishing 1st Pontrjagin class. We show that such algebras possess families of modules depending on infinitely many complex parameters, which we classify in terms of the corresponding algebra of twisted differential operators. If the underlying manifold is a flag manifold, our construction recovers modules over an affine Lie algebra parameterized by opers over the Langlands dual Lie algebra. The spaces of global sections of “smallest” such modules are irreducible [^(\mathfrakg)]{{\hat{{\mathfrak{g}}}}} -modules, and all irreducible \mathfrakg{{\mathfrak{g}}} -integrable [^(\mathfrakg)]{{\hat{{\mathfrak{g}}}}} -modules at the critical level arise in this way.     

Jacquet modules and Dirac cohomology

We show that Dirac cohomology of the Jacquet module of a Harish-Chandra module is a Harish-Chandra module for the corresponding Levi subgroup. We obtain an explicit formula of Dirac cohomology of the Jacquet module for most of the principal series, based on our determination of Dirac cohomology of irreducible generalized Verma modules with regular infinitesimal characters.     

Homological algebra for affine Hecke algebras

In this paper we study homological properties of modules over an affine Hecke algebra H. In particular we prove a comparison result for higher extensions of tempered modules when passing to the Schwartz algebra S, a certain topological completion of the affine Hecke algebra. The proof is self-contained and based on a direct construction of a bounded contraction of certain standard resolutions of H-modules.This construction applies for all positive parameters of the affine Hecke algebra. This is an important feature, since it is an ingredient to analyse how the irreducible discrete series representations of H arise in generic families over the parameter space of H. For irreducible non-simply laced affine Hecke algebras this will enable us to give a complete classification of the discrete series characters, for all positive parameters (we will report on this application in a separate article).     

带三角分解李代数的赋值模

设F是特征零的域，L是F上的带三角分解的李代数，L^-是相应的Loop代数．本文将定义L^-上赋值模的概念，并给出其不可约模的张量积是不可约模的等价条件．