偶交叉双积Hopf代数B RH的构造

本文给出了Doi Y.构造的偶交叉积B H的代数结构与Reshetikhim～N.构造的双代数BRH的余代数结构在张量空间B H上构成双代数(记为BRH)的充要条件,利用此结论具体构造了一个有趣的例子H4 KZ2,证明了当B,H均为Hopf.代数时BRH也为Hopf代数,最后给出这类双代数的映射刻划.     

偶交叉双积Hopf代数B_T_RH的构造

本文给出了DoiY．构造的偶交叉积BT■H的代数结构与ReshetikhimN．构造的双代数B■RH的余代数结构在张量空间B■H上构成双代数（记为Bτ■RH）的充要条件,利用此结论具体构造了一个有趣的例子B4■KZ2;证明了当B,H均为Hopf．代数时Bτ■RH也为Hopf代数,最后给出这类双代数的映射刻划。     

偶交叉双积Hopf代数B_T_RH的构造

本文给出了DoiY．构造的偶交叉积BT■H的代数结构与ReshetikhimN．构造的双代数B■RH的余代数结构在张量空间B■H上构成双代数（记为Bτ■RH）的充要条件,利用此结论具体构造了一个有趣的例子B4■KZ2;证明了当B,H均为Hopf．代数时Bτ■RH也为Hopf代数,最后给出这类双代数的映射刻划。     

Hopf代数的扭曲余积和H^R型Hopf代数

本文引进了Ｈｏｐｆ代数的扭曲余积，推广了广义偶交叉积，使得一般的右Ｓｍａｓｈ余积也是这里的特殊情况，讨论了Ｈ＾Ｒ型Ｈｏｐｆ代数与扭曲余积的关系。     

弱Hopf代数上的ω-交叉积

在弱Hopf代数上,定义了ω-交叉积概念,并给出了ω-交叉积是弱Hopf代数的充要条件,推广了弱Hopf代数的相应结论.     

Hopf代数的扭曲余积和H￣R型Hopf代数

本文引进了Ｈｏｐｆ代数的扭曲余积，推广了广义偶交叉积，使得一般的右Ｓｍａｓｈ余积也是这里的特殊情况，讨论了Ｈ￣Ｒ型Ｈｏｐｆ代数扭曲余积的关。     

弱Hopf代数上的扭积

在弱Hopf代数上,定义了交叉积概念,并且得到了它的两种特殊形式,冲积和扭积．特别地,给出了扭积为弱Hopf代数的一个充要条件,推广了Hopf代数的相应结论．     

弱Hopf代数上的扭积

在弱Hopf代数上,定义了交叉积概念,并且得到了它的两种特殊形式冲积和扭积.特别地,给出了扭积为弱Hopf代数的一个充要条件,推广了Hopf代数的相应结论.     

交叉积的同调维数

本文证明了当Ｈ是有限维半单和余半单的Ｈｏｐｆ代数时,Ｒ与交叉积Ｒ＃σＨ的整体维数是相同的;同时,它们的弱维数也是相同的．     

交叉积的同调维数

本文证明了当H是有限维半单和余半单的Hopf代数时,R与交叉积R#σH的整体维数是相同的;同时,它们的弱维数也是相同的.     

On Semisimple Hopf Algebras of Dimension 2 m

In this paper we classify all nontrivial semisimple Hopf algebras of dimension 2 ^{n +1} with the group of grouplikes isomorphic to _{2 n–1}×₂. Moreover, we extend some results on irreducible representations from groups to semisimple Hopf algebras and prove that certain semisimple Hopf algebras, including the ones classified in this paper, satisfy the generalized power map property.     

扭曲的自对偶Hopf代数

从两种重要的结构crossed积代数和扭曲Smash余积余代数出发,构造了一类新的Hopf代数R(?)K#_σH,并讨论它成为自对偶Hopf代数的条件.     

On Quasi-Bicrossed Products of Weak Hopf Algebras

The aim of this paper is to study quasi-bicrossed products and a especially quantum quasi-doubles. Firstly, we construct one new kind of quasi-bicrossed products by weak Hopf algebras and then devote a brief discussion to this matter. And, we discuss the conditions for quasi-bicrossed products to possess the structure of almost weak Hopf algebras, containing the case of a special smash product. At the end, we give some properties on the quantum quasi-double, respectively on the quasi-R-isomorphism, the representation-theoretic interpretation and the regularity of the quasi-R-matrix.     

Crossed Products for Weak Hopf Algebras

Weak crossed products by a weak bialgebra are defined. The resulting structure is not that of a unital algebra but an associative algebra with preunit. A general formula of such a product is given in terms of a weak 2-cocycle and a weak measuring. The relation with weak cleft extensions is studied. Equivalences of weak crossed products are defined and are related to gauge transformations. A relation between cleaving maps is described in terms of gauge transformations.     

On Smash Products Of Hopf Algebras

Let H = X? _R A denote an R-smash product of the two bialgebras X and A. We prove that (X,A) is a pair of matched bialgebras, if the R-smash product H has a braiding structure. When X is an associative algebra and A is a Hopf algebra, we investigate the global dimension and the weak dimension of the smash product H = X? _R A and show that lD(H) ≤ rD(A) + lD(X) and wD(H) ≤ wD(A) + wD(X). As an application, we get lD(H ₄) = ∞ for Sweedler's four dimensional Hopf algebra H ₄. We also study the associativity of smash products and the relations between smash products and factorization for algebras.     

Hopf代数的结构定理和对映阶数

本文中，我们把Ｈｏｐｆ代数的结构定理推广到Ｈｏｐｆ代数意义下的同构，从而给出Ｈｏｐｆ代数既约分支的对映阶数，并得到Ｈｏｐｆ代数扩张的对映阶数是任意的．这部分回答了Ｅ．Ｊ．Ｔａｆｔ１９９４年提出的一个问题．     

交叉余积上的Hopf代数结构

本文给出了Ｓｍａｓｈ积代数结构和交叉余积余代数结构构成双代数的一个充分必要条件．另外,还给出了这一新的双代数成为Ｈｏｐｆ代数的一个充分条件．     

Products of Linear Maps on Bialgebras,with Applications to Left Hopf Algebras and Hopf Algebroids

The Doi–Koppinen generalized smash product can be applied to linear maps on bialgebras, and we define a new associative product for linear maps on bialgebras. We comment on the applications of these products to left Hopf algebras and Hopf algebroids.     

Classifying Bicrossed Products of Hopf Algebras

Let A and H be two Hopf algebras. We shall classify up to an isomorphism that stabilizes A all Hopf algebras E that factorize through A and H by a cohomological type object ${\mathcal H}^{2} (A, H)$ . Equivalently, we classify up to a left A-linear Hopf algebra isomorphism, the set of all bicrossed products A???H associated to all possible matched pairs of Hopf algebras $(A, H, \triangleleft, \triangleright)$ that can be defined between A and H. In the construction of ${\mathcal H}^{2} (A, H)$ the key role is played by special elements of $CoZ^{1} (H, A) \times {\rm Aut}\,_{\rm CoAlg}^1 (H)$ , where CoZ ¹ (H, A) is the group of unitary cocentral maps and ${\rm Aut}\,_{\rm CoAlg}^1 (H)$ is the group of unitary automorphisms of the coalgebra H. Among several applications and examples, all bicrossed products H ₄???k[C _n ] are described by generators and relations and classified: they are quantum groups at roots of unity H _{4n, ω} which are classified by pure arithmetic properties of the ring ? _n . The Dirichlet’s theorem on primes is used to count the number of types of isomorphisms of this family of 4n-dimensional quantum groups. As a consequence of our approach the group Aut _Hopf(H _{4n, ω} ) of Hopf algebra automorphisms is fully described.