摘要
This paper introduces the concepts of cylinder coalgebras and cylinder coproducts for quasitriangular bialgebras, and points out that there exists an anti-coalgebra isomorphism (H,△^-)≌ (H,△^-), where (H, △^-) is the cylinder coproduct, and (H,△^-) is the braided coproduct given by Kass. For any finite dimensional Hopf algebra H, the Drinfel'd double (D(H),△^-D(H)) is proved to be the cylinder coproduct. Let (H, H, R) be copaired Hopf algebras. If R ∈ Z(H×H) with inverse R-1 and skew inverse R, then the twisted coalgebra (H^R)^R-1 is constructed via twice twists, whose comultiplication is exactly the cylinder coproduct. Moreover, for any generalized Long dimodule, some solutions for Yang-Baxter equations, four braid pairs and Long equations are constructed via cylinder twists.
本文引入两个概念,即,关于拟三角双代数的cylinder余代数和cylinder余积,并指出存在一个反余代数同构:(H,■)≌(H,■),其中(H,■)是cylinder余积,(H,■)是辫余积,对任意有限维Hopf代数H,我们证明Drinfel'd量子偶(D(H),■_(D(H)))是cylinder余积.设(H,H,R)是余配对Hopf代数,如果R∈Z(H■H),则通过两次扭曲,我们可以构造扭曲余代数(H~■)R^(-1),它的余乘法恰是cylinder余积.而且对任意的广义Long重模,通过cylinder扭曲,我们可以构造Yang-Baxter方程,四辫对和Long方程.
基金
the National Natural Science Foundation of China(10571153),and Postdoctoral Science Foundation of China(2005037713)