Relative Hopf modules—Equivalences and freeness criteria
نویسندگان
چکیده
منابع مشابه
A Quasi-hopf Algebra Freeness Theorem
We prove the quasi-Hopf algebra version of the Nichols-Zoeller theorem: A finite-dimensional quasi-Hopf algebra is free over any quasi-Hopf subalgebra.
متن کاملNEW CRITERIA FOR FREENESS IN ABELIAN GROUPS . H ( i )
A new criterion is established for an abelian group to be free. The criterion is in terms of an ascending chain of free subgroups and is dependent upon a new class of torsion-free groups. The result leads to the construction, for each positive integer n, of a group G of cardinality K that is not free but is X -free. A conjecture in infinitary logic concern71 n ing free abelian groups is also ve...
متن کاملRelative Egalitarianism and Related Criteria
We reconsider the problem of aggregating individual preference orderings into a single social ordering when alternatives are lotteries and individual preferences are of the von Neumann-Morgenstern type. Relative egalitarianism ranks alternatives by applying the leximin ordering to the distributions of (0-1) normalized utilities they generate. We propose an axiomatic characterization of this agg...
متن کاملCriteria to Disprove Context-Freeness of Collage Languages
Collage grammars generate picture languages in a context-free way. The generating process is based on the replacement of atomic nonterminal items and can be seen as an adaptation of the notion of hyperedge replacement known from the area of context-free graph generation. While a pumping lemma holds for hyperedge replacement graph grammars and is quite useful to show that certain graph languages...
متن کاملOn the Cohomology of Relative Hopf Modules
Let H be a Hopf algebra over a field k, and A an Hcomodule algebra. The categories of comodules and relative Hopf modules are then Grothendieck categories with enough injectives. We study the derived functors of the associated Hom functors, and of the coinvariants functor, and discuss spectral sequences that connect them. We also discuss when the coinvariants functor preserves injectives.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Algebra
سال: 1979
ISSN: 0021-8693
DOI: 10.1016/0021-8693(79)90093-0