秩1量子群表示的滤过

设U是A＝Z[v1/2]M上相伴于对称Cartan矩阵的量子群，式中M是Z[v1/2]的由v1/2-1和某奇素数p生成的理想．本文证明了两个δ（U）模嵌入和两个δ（U）模同态，构造了HO（U／UO；λm）和HO（U／UO，λm-2t）的δ（U）模游过．特别地，当2（P－1）≤m＜p2，k为A的剩余域时，证明了HO（Uk／UOK，λm）和HO（UK／UOK，λm-2（p-1））的δ（UK）滤过分别在HO（UK／UbK，λm）和H1（Uk／Ubk，λ－m-2）上的限制就是半单线性代数群中的Andersen滤过[2]     

量子群的基变换与范畴同构

令Ｍ是Ｚ［ｖ］的由ｖ－１和奇素数ｐ生成的理想,Ｕ是Ａ＝Ｚ［ｖ］Ｍ上相伴于对称Ｃａｒｔａｎ矩阵的量子群, Ａ－Γ是环同态, Ｕг＝ＵＡΓ［Ｕг］是Ｕг的量子坐标代数,本文建立了量子坐标代数的基变换：即在相关约束条件下有Г－Ｈｏｐｆ同构 Ａ［Ｕ］ＡГ≌Г［Ｕг］．我们证明了有限秩 Ａ自由 １型可积 Ｕ模范畴和有限秩 Ａ自由 Ａ［Ｕ］余模范畴是同构的．特别,当 Г是域时,局部有限 １型 Ｕг模范畴和Г［Ｕг］余模范畴是同构的．最后,我们还证明了在［１］中定义的诱导函子和Ｂ．Ｐａｒｓｈａｌｌ与王建磐博士在［２］中研究的诱导函子的一致性．     

量子群V_q(sl(2))的商代数

本文研究当q是单位根时,V_q(sl(2))在关系H~r=K~r=1,E~(mr)=F~(nr)=0下的商代数V_q(m,n)的构造与分解,以及它的区块结构.为此,首先将U_q(sl(2))的基本性质和重要结论推广到V_q(sl(2)),并研究V_q(sl(2))的模的基本性质.利用这些结论,我们逐步构造出V_q(m,n)的左理想,并将V_q(m,n)分解成不可分解的左理想的直和.然后,把V_q(m,n)的不可分解的左理想合并成区块,并研究区块结构,从而把V_q(m,n)的表示问题归结成一个代数表示论的问题.     

紧矩阵量子群G的余表示与其对偶量子群的关系

设 G=（A,△）为紧矩阵量子群,G为A的所有有限维光滑的、不可约余表示等价类的集合.本文通过（A,△）的一个余表示Vo构造了两个相互配对的集合,利用Hilbert C＊-模的理论证明它们分别为A和Baaj与Skandalis构造的量子群A,并且证明了对任意的α∈G,在A中都对应一个有限维投影算子Pα,满足 dim（α）=dim（pα）.     

紧矩阵量子群G的余表示与其对偶量子群(A)的关系

设 G=（A,△）为紧矩阵量子群,G为A的所有有限维光滑的、不可约余表示等价类的集合.本文通过（A,△）的一个余表示Vo构造了两个相互配对的集合,利用Hilbert C＊-模的理论证明它们分别为A和Baaj与Skandalis构造的量子群A,并且证明了对任意的α∈G,在A中都对应一个有限维投影算子Pα,满足 dim（α）=dim（pα）.     

形变预投射代数与量子群的表示

设$(Gamma, I)$是约束循环箭图, 其顶点对应于Abel群$Z_d$. 给出了所有 $(Gamma, I)$的不可分解表示以及其中可扩张成相应形变预投射代数 $Pi^lambda(Gamma, I)$的不可分解表示的条件. 证明了由$(Gamma, I)$的 可扩张不可分解表示提升得到的$Pi^lambda(Gamma, I)$的表示一定是其 所有单表示, 从而通过形变预投射代数的方式实现了限制量子群 $ol{U}_q({rm sl}_2)$的所有单表示.     

紧量子群U_θ（2）的分类

本文将要证明紧量子群Uθ（2）的余表示完全由其无穷小生成元B0,B2,A0,A1与A2决定,其中θ为无理数.还将证明B0,B2与Aj交换,j=0,1,2,B0,A0,A1,A2生成了sl（2,C）的loop代数.而后我们将给出Uθ（2）的所有不可约表示,不同于古典酉群U（2）的表示,最后利用上述结论给出Uθ（2）的分类,这个分类相似于无理旋转代数Aθ的分类,同时刻画了Uθ（2）所有自同构.     

量子群U_q(sl(2 ) )的非负部分(英文)

设U≥ 0 是量子群Uq(sl(2 ) )的非负部分 .在本文中 ,我们确定了U≥ 0 的中心Z(U≥ 0 )和U≥ 0 的所有不可约表示     

秩1量子群的有限维表示的扩张与诱导模的零化性质

量子群表示的扩张归结为秩1群的扩张.本文研究了秩1量子群有限维表示的扩张结构和诱导模的零化性质,给出了有限维 U_k~b 表示扩张成 U_k 表示的充要条件.对任一有限维 U_k~b模 V,给出了诱导模 H_k~0(V)是非零的充要条件.     

A Class of Finite-Dimensional Representations of U_q（sl_2）

In order to study a class of finite-dimensional representations of Uq（sl2）, we deal with the quotient algebra Uq （m, n, b） of quantum group Uq（sl2） with relations Kr=1, Emr=b, Fnr=0 in this paper, where q is a root of unity. The algebra Uq（m, n, b） is decomposed into a direct sum of indecomposable （left） ideals. The structures of indecomposable projective representations and their blocks are determined.     

Monomial Realization of Crystal Bases <Emphasis Type=Italic>B</Emphasis>(∞) for the Quantum Finite Algebras

In this paper, we give a new realization of the crystal basis B(∞) using modified Nakajima monomials for the quantum finite algebras. Moreover, as an application, we obtain the image of the Kashiwara embedding Ψ _ι from this realization of B(∞). Presented by Alain Verschoren.     

Counting the number of indecomposable representations and a q-analogue of the Weyl-Kac denominator identity of type _n

By using Frobenius maps and F-stable representations,we count the number of isomor- phism classes of indecomposable representations with the fixed dimension vector of a species of type _n over a finite field,first,and then,as an application,give a q-analogue of the Weyl-Kac denominator identity of type _n.     

On the asymptotic distribution of the spectrum of an operator over irreducible representations of its symmetry group

We show that a representation of a finite group in the eigenfunction space of an elliptic operator defined on a Riemannian manifold and commuting with the effective action of the group is asymptotically a multiple of the regular representation of the group.     

On Racah operators

As a generalization of the well-known Racah coefficients (defined for finite-dimensional representations of semisimple Lie groups), we introduce the notion of Racah operators for locally compact groups with “nice” dual space. In the case of the group PSL(2,?), these operators are explicitly indicated.     

Racah operators for the group of motions

The author [5] introduced Racah operators for unitary representations of topological groups of type I. In the present paper, we indicate the explicit form of these operators for representations of the group of motions of three-dimensional Euclidean space.     

Harmonic spinors on semisimple symmetric spaces

Let G/H be a semisimple symmetric space. We consider a Dirac operator D on G/H twisted by a finite dimensional H-representation. We give an explicit integral formula for certain solutions of the equation D=0. In particular, some quotients of standard principal series representations are seen to occur in the kernel of D.     

Spanning L 2 of a nilpotent Lie group by eigenvectors of invariant differential operators

Let be a non-abelian, connected, simply connected, nilpotent Lie group. We show that the eigenvectors of a finite number of families of left invariant differential operators and their conjugates span a dense subspace of L ² (G). The restriction of the left regular representation to each one of these (left invariant) eigenspaces disintegrates into irreducible unitary representations with multiplicities 0 and 1 only. J. Ludwig and C. Molitor-Braun are supported by the research grant R1F104C09 of the University of Luxembourg.