Some Algebras Similar to the Enveloping Algebra of s1(2)

Abstract

Consider the algebra R = ?[A,B,H] subject to relations

where and . We study these algebras for different f and ç. We study highest weight modules and finite dimensional simple modules. We introduce the categories ^p with p ≥ 1, with an interesting decomposition in categories ^p _I and ^p _II . We also consider the BGG-category and develop new techniques towards the study of .     

Free subgroups in maximal subgroups of GLn(D)

Let D be a noncommutative finite dimensional F-central division algebra and M a noncommutative maximal subgroup of GL_n(D). It is shown that either M contains a noncyclic free subgroup or M is absolutely irreducible and there exists a unique maximal subfield K of M_n(D) such that K*M, K∕F is Galois with Gal(K∕F)?M∕K* and Gal(K∕F) is a finite simple group.     

量子代数${\cal U}_q(f(K,H))$的量子伴随作用

Let H = uq（sl（2）） or u（sl（2））. By means of the standard basis of polynomial algebras, the Glebsch-Gordan formula and quantum Clebsch-Gordan formula are proved by a unified method, and the explicit formula of the decomposition of V（1）^n into the direct sum of simple modules is given in this paper.     

六类Oberwolfach问题OP(4~a,s~b)的解

完全图K_n(n为奇数)或K_n-I(n为偶数,I为K_n的1-因子)是否有2-因子分解称Oberwolfach问题.每个2-因子恰包含α_i个长为m_i的圈(i=1,2,…,t)的Oberwolfach问题记为OP(m_1~(α_1),m_2~(α_2),…,m_t~(α_t)).证明了对任意的a≥0,b=2,3和s=3,5,6,且(a,s,b)≠(0,3,2),都存在OP(4~a,s~b)的解.     

Maximal Subgroups of Subnormal Subgroups of GL n (D) with Finite Conjugacy Classes

Let D be an infinite division ring. A famous result due to Herstein says that every noncentral element of D has infinitely many conjugates in D. So, if D* is an FC-group, then D is a field. Now let N be a subnormal subgroup of GL _n (D), where n ≥ 1, and M a maximal subgroup of N. In this article, we prove that if M is an FC-group, then M is contained in the multiplicative group of some subfield of M _n (D).     

SL(n,C)上一类特殊可解子群的结构及其在Fuchs系统中的应用

给出了SL(n,C)中一类特殊的具有有限个生成元的可解子群的结构定理.由单值群的可解性与Fuchs系统的可积性之间的关系,研究对应的单值群是可解的环面上只有一个正则起点的n阶Fuchs方程的解Riemann曲面结构,进而研究其解的大范围性质.     

The Jacobson Radical of （R[G]）^G

In this paper,the Jacobson radical of (R[G])G, the fixed point subring of a group ring (R[G]) is studied. Some related properties of (R[G])G are discussed.     

几类非Abel群之增广商群的结构

记ZG为有限群G的整群环,△n(G)为增广理想△(G)的n次幂,Qn(G)=△"(G)/△n 1(G)为G的增广商群.本文考虑了二面体群D2tk(k 奇)和m次对称群Sm,证明了Qn(D2tk)为秩不超过2t 1的基本2-群以及Qn(Sm)≌Z2.     

绝对稳定性的一个充要性准则及其在四阶系统中的应用

本文给出绝对稳定性的一个充要性准则.叙述了它对四阶系统的具体应用.     

A Duality Theorem Associated with the Smash Product of Graded Ring and G-set

ＬｅｔＲｂｅａＧ－ｇｒａｄｅｄｒｉｎｇｗｉｔｈｉｄｅｎｔｉｔｙ１；ｔｈａｔｉｓＲｇ∈ＧＲｇａｎｄＲｇＲｈＲｇｈｆｏｒａｌｌｇ，ｈ∈Ｇ．ＴｈｅａｓｓｏｃｉａｔｉｖｅｒｉｎｇＲ＃ＧｄｅｎｏｔｅｓｔｈｅｓｍａｓｈｐｒｏｄｕｃｔｆｏｒｔｈｅｇｒｏｕｐＧａｎｄｔｈｅｇｒａｄｅｄｒｉｎｇＲ（ｓｅｅ［３］ｏｒ［４］）．Ｉｎ［１］，ＣｏｈｅｎａｎｄＭｏｎｔｇｏｍｅｒｙｐｒｏｖｅｄｔｈｅｄｕａｌｉｔｙＴｈｅｏｒｅｍｓｆｏｒａｃｔｉｏｎｓａｎｄｃｏａｃｔｉｏｎｓｆｏｒｆｉｎｉｔｅｇｒｏｕｐＧ．Ｉｎ［２］，ａｆ…     

On the Structure of the Augmentation Quotient Group for Some Non-abelian p-groups

In this paper,we study the basis of augmentation ideals and the quotient groups of finite non-abelian p-group which has a cyclic subgroup of index p,where p is an odd prime,and k is greater than or equal to 3.A concrete basis for the augmentation ideal is obtained and then the structure of its quotient groups can be determined.     

Haar锥逼近的交错定理及其在系数有界逼近中的应用

本文首先推广了Ｐ．Ｐｅｉｓｋｅｒ １９８３年给出的Ｈａａｒ锥的定义及Ｈａａｒ锥一致逼近的交错定量，然后得到了Ｈａａｒ锥根数的一种求法。利用这些结果，讨论了系数有界限逼近的特征问题，特别是给出了系数有界限的代数多项式逼近与广义Ｂｅｒｎｓｔｅｉｎ多项式逼近的使用十分方便的交错定理。     

关于HSOLSSOM（2^nu^1）的谱

本文讨论型为２＾ｎｕ＾１的有对称正交侣的带洞自正交拉丁方（ＨＳＯＬＳＳＯＭ（２＾ｎｕ＾１））的谱。证明当ｎ≤９时,ＨＳＯＬＳＳＯＭ（２＾ｎｕ＾１）存在的充分必要条件是ｕ为偶数且ｎ≥３ｕ／２＋１;当ｎ≥２６３时,若ｕ为偶数且ｎ≥２（ｕ－２）,则ＨＳＯＬＳＳＯＭ（２＾ｎｕ＾１）存在。     

Normal subgroups ofSL 1,D and the classification of finite simple groups

LetD be a division algebra of degree three over an algebraic number fieldK and let G = SL_D. We prove that the normal subgroup structure of G(K) is given by the Platonov-Margulis conjecture. The proof uses the classification of finite simple groups.     

Existence of a-fold Perfect （v, {5, 8}, 1）-Mendelsohn Designs

Let v be a positive integer and let K be a set of positive integers. A （v, K, 1）-Mendelsohn design, which we denote briefly by （v, K, 1）-MD, is a pair （X, B） where X is a v-set （of points） and B is a collection of cyclically ordered subsets of X （called blocks） with sizes in the set K such that every ordered pair of points of X are consecutive in exactly one block of B. If for all t =1, 2,..., r, every ordered pair of points of X are t-apart in exactly one block of B, then the （v, K, 1）-MD is called an r-fold perfect design and denoted briefly by an r-fold perfect （v, K, 1）-MD. If K = {k） and r = k - 1, then an r-fold perfect （v, （k）, 1）-MD is essentially the more familiar （v, k, 1）-perfect Mendelsohn design, which is briefly denoted by （v, k, 1）-PMD. In this paper, we investigate the existence of 4-fold perfect （v, （5, 8}, 1）-Mendelsohn designs.     

量子群Uq(D4)上不可约模的Grobner-Shirshov对

首先,利用量子群Uq (D4)的已知的Grobner-Shirshov基和Chibrikov的双自由模方法来计算量子群Uq(D4)上不可约模Vq(λ)的一个Grobner-Shirshov对,然后在Uq(D4)的适当形式U'q(D4)中取q=1得到D4型单李代数的泛包络代数U(D4)上不可约模V(λ)的一个Grobner-Shirshov对.     

Structure Theorems for Group Ring Codes with an Application to Self-Dual Codes

Using ideas from the cohomology of finite groups, an isomorphism is established between a group ring and the direct sum of twisted group rings. This gives a decomposition of a group ring code into twisted group ring codes. In the abelian case the twisted group ring codes are (multi-dimensional) constacyclic codes. We use the decomposition to prove that, with respect to the Euclidean inner product, there are no self-dual group ring codes when the group is the direct product of a 2-group and a group of odd order, and the ring is a field of odd characteristic or a certain modular ring. In particular, there are no self-dual abelian codes over the rings indicated. Extensions of these results to non-Euclidean inner products are briefly discussed.     

单因环的性质、等价条件和结构

一个有单位元的结合环，如果其元素不是单位就是零因子，则称其为单因环。它是很广泛的一个环类．本文讨论了单因环的住质、等价条件和结构；还讨论了它同其它环诸如正则环、局部环和循环环的关系，从而较深刻地刻划了这种环。     

具有两个生成元的SL2(C)的可解子群构造及对Fuchs系统的应用

本文给出ＳＬ₂（Ｃ）中具有两个生成元的可解子群的结构定理,并由单值群的可解性定义一类环面Ｔ²上Ｆｕｃｈｓ系统的可积性,进而研究该系统的解的一些大范围性质．