Kac-Moody群上可微分模的刻画

对Ｋａｙ－Ｍｏｏｄｙ代数ｇ′上的任意可积模（Ｖ，ｄπ），通过指数可以把它提升为同ｇ′关联的Ｋａｃ－Ｍｏｏｄｙ群Ｇ上的模（Ｖ，π），Ｇ上的这种模称为可微分模．本文将刻画Ｇ上的可微分模并且证明，模（Ｖ，π）是可微分模当且仅当Ｖ到每个根子群Ｕ_ａ的限制都是Ｕ_ａ的一个有理表示．依据这种刻画，得到一个有趣的结果：有理数域Ｑ上的Ｃｈｅｖａｌｅｙ群Ｇ（Ｑ）的所有有限维模都是可微分模     

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。     

广义微分算子的谱

本文利用经典的角度量的方法，研究了由Ｒ－Ｎ导数定义的广义微分算子Ｌ的谱性质，这种性质以前尚未被研究过。文章共分三部分：（一）给出广义微分算子Ｌ的定义，并介绍了文中涉及的一些概念；（二）给出文中要用到的一些已知定理；（三）通过讨论角度变量θ（ｘ，λ），得出算子Ｌ的一些谱性质．     

Doi-Hopf模以及其上的平坦联络

对于任意Hopf代数,在其上建立了一种新的具有非交换微分几何形式的代数结构,并论证了Doi-hopf模与具有平坦联络的模之间是同构的,其中,联络对应于我们所给的微分算子.     

除环上矩阵的保逆线性算子

除环上矩阵的保逆线性算子曹重光（黑龙江大学数学系，哈尔滨１５００８０）关键词除环，逆矩阵，线性算子．分类号ＡＭＳ（１９９１）１５Ａ０４，１５Ａ３３／ＣＣＬＯ１５１．２１设Ｒ是一个除环，Ｆ为其中心域，又设ｃｈａｒＲ≠２，３；Ｗ＿ｎ（Ｒ）及Ｓ＿ｎ（Ｒ）分...     

Vilenkin群上的Gibbs-Butzer微分算子 *

在局部紧Vilenkin群(简称V群)上定义仿微分算子、讨论它的主要性质;借助仿线性化基本定理,研究Gibbs-Butzer(简称G-B)微分算子,并给出该类算子应用的例.     

交换整环上的上三角矩阵保对合的线性算子

本文刻划了交换整环Ｒ上的上三角长阵的Ｒ－代数Ｆｎ（Ｒ）的保对合的可逆线性算子，由此又确定了Ｆｎ（Ｒ）的保立方幂等的可逆线性算子。     

广义Calderón Zygmund算子及其加权模不等式

本文推广Coifman和Meyer的Calderon-Zygmund算子概念,定义了M-型和θ-型广义Calderon-Zygmund算子,证明了它们的L~p有界性。然后对θ-型Calde-ron-Zygmund算子证明L~p加权模不等式。由于θ-型Calderon-Zygmund算子的广泛性,这就不但对已有的一些算子的加权模不等式给出了新的证明,同时还得到了一系列新的结果,其中包括各种类型的伪微分算子和交换子的加权模不等式。接着讨论具有较高阶光滑性条件的C~N-型Calderon-Zygmund算子,得到H~p到L~p有界性结果。最后通过把Calderon-Zygmund算子推广到向量值函数,并借助Little-wood-Paley理论,对Caifman和Meyer的一类广义伪微分算子和Meyer的一类广义伪微分算子得到加权模不等式。     

复随机内积模上一类算子的谱定理

本文给出复随机内积模上几乎处处有界线性算子谱的几个基本定理，这些定理不但为随机内积模上几乎处处有界线性算子的进一步讨论有基本重要性，而且也为Ｈｉｌｂｅｒｔ空间上连续随机算子的谱研究提供了一个新途径。     

Zygmund空间上的微分复合算子

讨论Zygmund空间E={f∈H(D):sup_(z∈D)(l-|z|~2)|f″(z)|∞}上的微分复合算子DC_φ,这里C_φ是复合算子,D是微分算子.得到了DC_φ在Zygmund空间E和小Zygmund空间E_0上是有界算子与紧算子的充分必要条件.     

Irregular Wakimoto modules and the Casimir connection

We study some non-highest weight modules over an affine Kac–Moody algebra [^(\mathfrak g)]{\hat{\mathfrak g}} at the non-critical level. Roughly speaking, these modules are non-commutative localizations of some non-highest weight “vacuum” modules. Using free field realization, we embed some rings of differential operators in endomorphism rings of our modules. These rings of differential operators act on a localization of the space of coinvariants of any [^(\mathfrak g)]{\hat{\mathfrak g}}-module with respect to a certain level subalgebra. In a particular case this action is identified with the Casimir connection.     

Relative Reduction and Buchberger’s Algorithm in Filtered Free Modules

In this paper we develop a relative Gröbner basis method for a wide class of filtered modules. Our general setting covers the cases of modules over rings of differential, difference, inversive difference and difference–differential operators, Weyl algebras and multiparameter twisted Weyl algebras (the last class of rings includes the classes of quantized Weyl algebras and twisted generalized Weyl algebras). In particular, we obtain a Buchberger-type algorithm for constructing relative Gröbner bases of filtered free modules.     

Invariant Differential Operators and FCR Factors of Enveloping Algebras

If  is a semisimple Lie algebra, we describe the prime factors of  () that have enough finite dimensional modules. The proof depends on some combinatorial facts about the Weyl group which may be of independent interest. We also determine, which finite dimensional  ()-modules are modules over a given prime factor. As an application we study finite dimensional modules over some rings of invariant differential operators arising from Howe duality.     

Honest submodules

Lattices of submodules of modules and the operators we can define on these lattices are useful tools in the study of rings and modules and their properties. Here we shall consider some submodule operators defined by sets of left ideals. First we focus our attention on the relationship between properties of a set of ideals and properties of a submodule operator it defines. Our second goal will be to apply these results to the study of the structure of certain classes of rings and modules. In particular some applications to the study and the structure theory of torsion modules are provided.     

On Computing Gröbner Bases in Rings of Differential Operators with Coefficients in a Ring

Following the definition of Gr?bner bases in rings of differential operators given by Insa and Pauer (1998), we discuss some computational properties of Gr?bner bases arising when the coefficient set is a ring. First we give examples to show that the generalization of S-polynomials is necessary for computation of Gr?bner bases. Then we prove that under certain conditions the G-S-polynomials can be reduced to be simpler than the original one. Especially for some simple case it is enough to consider S-polynomials in the computation of Gr?bner bases. The algorithm for computation of Gr?bner bases can thus be simplified. Last we discuss the elimination property of Gr?bner bases in rings of differential operators and give some examples of solving PDE by elimination using Gr?bner bases. This work was supported by the NSFC project 60473019.     

The lattice structure of preradicals III: operators

We continue the study of the big lattice of preradicals over a ring. We consider several operators acting on this lattice, for instance the pseudocomplement, the annihilator and the totalizer, as well as some relations among them. Using some of these operators we give characterizations of V-rings, of rings that are a finite direct sum of injective hulls of simple modules, and of rings such that besides the latter condition have also the property that each pair of simple modules are homologically connected.     

Class and rank of differential modules

A differential module is a module equipped with a square-zero endomorphism. This structure underpins complexes of modules over rings, as well as differential graded modules over graded rings. We establish lower bounds on the class – a substitute for the length of a free complex – and on the rank of a differential module in terms of invariants of its homology. These results specialize to basic theorems in commutative algebra and algebraic topology. One instance is a common generalization of the equicharacteristic case of the New Intersection Theorem of Hochster, Peskine, P. Roberts, and Szpiro, concerning complexes over commutative noetherian rings, and of a theorem of G. Carlsson on differential graded modules over graded polynomial rings.     

Gorenstein n-X-Injective and n-X-Flat Modules with Respect to a Special Finitely Presented Module

Let R be a ring,X a class of R-modules and n ≥ 1 an integer.We intro-duce the concepts of Gorenstein n-X-injective and n-X-flat modules via special finitely presented modules.Besides,we obtain some equivalent properties of these modules on n-X-coherent rings.Then we investigate the relations among Gorenstein n-X-injective,n-X-flat,injective and fiat modules on X-FC-rings (i.e.,self n-X-injective and n-X-coherent rings).Several known results are generalized to this new context.     

D_4型广义扭仿射李代数及其模

本文是[3]的继续,将讨论D4型的广义扭仿射李代数及其表示理论;证明作用在其不可约模上的一类算子的局部幂零性.     

A Dichotomy for the Gelfand–Kirillov Dimensions of Simple Modules over Simple Differential Rings

The Gelfand–Kirillov dimension has gained importance since its introduction as a tool in the study of non-commutative infinite dimensional algebras and their modules. In this paper we show a dichotomy for the Gelfand–Kirillov dimension of simple modules over certain simple rings of differential operators. We thus answer a question of J. C. McConnell in Representations of solvable Lie algebras V. On the Gelfand-Kirillov dimension of simple modules. McConnell (J. Algebra 76(2), 489–493, 1982) concerning this dimension for a class of algebras that arise as simple homomorphic images of solvable lie algebras. We also determine the Gelfand–Kirillov dimension of an induced module.