The crystal duality principle: From Hopf algebras to geometrical symmetries

Braided Hopf Algebras Obtained from Coquasitriangular Hopf Algebras

Let (H, σ) be a coquasitriangular Hopf algebra, not necessarily finite dimensional. Following methods of Doi and Takeuchi, which parallel the constructions of Radford in the case of finite dimensional quasitriangular Hopf algebras, we define Hσ , a sub-Hopf algebra of H, the finite dual of H. Using the generalized quantum double construction and the theory of Hopf algebras with a projection, we...

Structures in Feynman Graphs - Hopf Algebras and Symmetries

We review the combinatorial structure of perturbative quantum field theory with emphasis given to the decomposition of graphs into primitive ones. The consequences in terms of unique factorization of Dyson– Schwinger equations into Euler products are discussed.

On the Coderivations of Some Hopf Algebras

Duality and Rational Modules in Hopf Algebras over Commutative Rings

Let A be an algebra over a commutative ring R. If R is noetherian and A◦ is pure in R, then the categories of rational left A-modules and right A◦-comodules are isomorphic. In the Hopf algebra case, we can also strengthen the Blattner– Montgomery duality theorem. Finally, we give sufficient conditions to get the purity of A◦ in R. © 2001 Academic Press

Duality for Finite Hopf Algebras Explained by Corings

We give a coring version for the duality theorem for actions and coactions of a finitely generated projective Hopf algebra. We also provide a coring analogue for a theorem of H.-J. Schneider, which generalizes and unifies the duality theorem for finite Hopf algebras and its refinements.