Hopf Algebra Coaction and Its Application to Group-Graded Rings
Let H be a Hopf algebra, A a right H-comodule algebra and A#H * a right smash product. Chen and Cai give a Morita context connection between A coH and A#H *rat under the assumption that ∫ H* r = ∫ H* l ≠ 0. In this paper we form a Morita context connection between A coH and A#H *rat under the condition ∫ H* l ≠ 0. We apply the results to G-graded algebras and give a Maschke type theorem for G-graded algebras.
KeywordsHopf Algebra Direct Summand Sition Inverse Smash Product Nonzero Idempotent
Unable to display preview. Download preview PDF.
- M. E. Sweedler, Hopf Algebras,Benjamin,New York, 1969.Google Scholar