Return to search

FREENESS OF HOPF ALGEBRAS OVER GROUPLIKE SUBALGEBRAS

Throughout, H is a Hopf algebra over a field k of characteristic p, G(H) is the group of grouplikes of H and L is any subgroup of G(H). We denote the antipode of H by S. We investigate the freeness of Hopf algebras as modules over their group algebras of grouplikes. / In chapter II we consider semisimple group algebras kL. We prove that for finite dimensional H all nonzero objects in the category (' )(, ) of left (H,kL)-Hopf modules are free kL-modules. We also prove this in the case when S('2) = id. Hence, for a finite dimensional H, the number of one-dimensional ideals divides the dimension of H and the order of S divides 4(.)dimension of H. / In chapter III we prove that a finite dimensional H is a free k-module for any g (ELEM) G(H), even if p divides the order of g. Further we establish that a finite dimensional H is a free kL-module if and only if H is a free kA-module for any elementary abelian p-subgroup A of L. / In chapter IV we prove that a finite dimensional H over an algebraically closed field k of characteristic p is a free kL-module, if H does not contain any simple subcoalgebra of dimension (lp)('2) for any natural number 1 (GREATERTHEQ) 2. Further we construct an example of an infinite dimensional H showing that not all objects in (' )(, ) are free kL-modules. Finally we show that any infinite dimensional H is a free kL-module, if L is an infinite group which contains no nontrivial finite subgroup. Also, if the dimension of H equals the dimension of the coradical of H, then H is a free module over any of its semisimple group algebras k where g (ELEM) G(H). / Source: Dissertation Abstracts International, Volume: 47-01, Section: B, page: 0246. / Thesis (Ph.D.)--The Florida State University, 1985.

Identiferoai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_75766
ContributorsZOELLER, MARTHA BETTINA., Florida State University
Source SetsFlorida State University
Detected LanguageEnglish
TypeText
Format91 p.
RightsOn campus use only.
RelationDissertation Abstracts International

Page generated in 0.0017 seconds