We prove new necessary and sufficient conditions for a morphism of coalgebras to be a monomorphism, different from the ones already available in the literature. More precisely, φ: C → D is a monomorphism of coalgebras if and only if the first cohomology groups of the coalgebras C and D coincide if and only if for all . In particular, necessary and sufficient conditions for a Hopf algebra map to be a monomorphism are given.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-cm120-1-11, author = {A. L. Agore}, title = {Monomorphisms of coalgebras}, journal = {Colloquium Mathematicae}, volume = {120}, year = {2010}, pages = {149-155}, zbl = {1196.16031}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-cm120-1-11} }
A. L. Agore. Monomorphisms of coalgebras. Colloquium Mathematicae, Tome 120 (2010) pp. 149-155. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-cm120-1-11/