Coaction on a finite dual of a Hopf algebra - MathOverflow most recent 30 from http://mathoverflow.net 2013-05-24T22:03:54Z http://mathoverflow.net/feeds/question/47701 http://www.creativecommons.org/licenses/by-nc/2.5/rdf http://mathoverflow.net/questions/47701/coaction-on-a-finite-dual-of-a-hopf-algebra Coaction on a finite dual of a Hopf algebra Neha 2010-11-29T18:01:21Z 2010-11-29T18:01:21Z <p>If $H$ is a central hopf subalgebra of a Hopf algebra $A$. Let $\phi:A\rightarrow A\otimes H$ be a coaction of $H$ on $A$. When does $A^\circ$ becomes a $H^{*}$-submodule i.e. is $A^\circ$ an $H$-subcomodule? Basically I want to realize given a coaction of $H$ on $A$, does it imply a coaction of $H$ on the finite dual of $A$ as well: $$A^\circ\rightarrow A^\circ\otimes H \hspace{8 pt}?$$</p>