On Standard Ideals

In the paper,we study a class of standard ideals which are more general than the m-primary standared ideals discussed in[2].We will prove an important equality concerning I-weak sequences;thus a generalization of the equality of [2] is established.     

On Some Problems Studied by R. V. Kadison

Several problems studied by professor R. V. Kadison are shown to be closely related. The problems were originally formulated in the contexts of homomorphisms of C^*-algebras, cohomology of von Neumann algebras and perturbations of C^*-algebras. Recent research by G. Pisier has demonstrated that all of the problems considered are related to the question of whether all C^*-algebras have finite length.     

Graded Hochschild cohomology of a path algebra with oriented cycles

The aim of this paper is to characterize the first graded Hochschild cohomology of a hereditary algebra whose Gabriel quiver is admitted to have oriented cycles. The interesting conclusion we have obtained shows that the standard basis of the first graded Hochschild cohomology depends on the genus of a quiver as a topological object. In this paper, we overcome the limitation of the classical Hochschild cohomology for hereditary algebra where the Gabriel quiver is assumed to be acyclic. As preparation, we first investigate the graded differential operators on a path algebra and the associated graded Lie algebra.     

Cofiniteness of Lo cal Cohomology Mo dules with Resp ect to a Pair of Ideals

Let R be a commutative Noetherian ring, I and J be two ideals of R, and M be an R-module. We study the cofiniteness and finiteness of the local cohomology module HiI,J（M） and give some conditions for the finiteness of HomR（R/I, HsI,J（M）） and Ext1R（R/I, HsI,J（M））. Also, we get some results on the attached primes of HdimMI,J （M）.     

离散流上的不变测度与上同调

讨论一离散流上不变测度的存在性 ,在 (Ω ,m0 )是一般概率测度空间 ,T是Ω上遍历自同构 ,f∈L¹(Ω ,m0 )时 ,建立上同调函数方程 f =h°T -h具有解h∈L²(Ω ,m0 )的一组等价条件 ,进而给出h的表达式 ,即得到关于Kachurovskii猜想的进一步结论     

一个Cluster-Tilted代数的Hochschild同调与循环同调

基于Furuya构造的一个Cluster-Tilted代数的极小投射双模分解,用组合的方法计算了Cluster-Tilted代数的Hochschild同调空间的维数与基.当基础域的特征为零时,也计算了代数的循环同调群的维数.     

三角矩阵上的Hochschild 2-循环广义若当导子

In this paper,we prove that every generalized Jordan derivation associate with a Hochschild 2-cocycle from the algebra of upper triangular matrices to its bimodule is the sum of a generalized derivation and an antiderivation.     

一类自入射Koszul特殊双列代数的Hochschild同调群

基于Snashall与Taillefer构造的极小投射双模分解,用组合的方法,清晰地计算出一类自入射Koszul特殊双列代数∧_N的各阶Hochschild同调群的维数,从而以计算的方式直观地表明了韩阳的猜想对这类代数∧_N成立.     

李超代数gl_(2|1)到Witt超代数的低维上同调

Witt超代数在伴随表示的意义下是一般线性李超代数gl_(2|1^-)模.通过对Witt超代数进行子模分解和权空间分解,用简约的方法计算了gl_(2|1-)模.通过对Witt超代数进行子模分解和权空间分解,用简约的方法计算了gl_(2|1^-)到Witt超代数的低维上同调.     

Some Results for Formal Local Cohomology Modules

Let （R, m） be a commutative Noetherian local ring, I an ideal of R and M a finitely generated R-module. Let limnHm^i（M/I^nM）be the ith formal local cohomology module of M with respect to I.In this paper, we discuss some properties of formal local cohomology modules limnHm^i（M/I^nM）,which are analogous to the finiteness and Artinianness of local cohomology modules of a finitely generated module.