Slenderness, Completions, and Duality for Primary Abelian Groups
β Scribed by Patrick Keef
- Publisher
- Elsevier Science
- Year
- 1997
- Tongue
- English
- Weight
- 191 KB
- Volume
- 187
- Category
- Article
- ISSN
- 0021-8693
No coin nor oath required. For personal study only.
β¦ Synopsis
If A is a fixed abelian group with endomorphism ring E, then for any group G, Ε½ . Ε½ . let G* s Hom G, A and for any E-module M, let M* s Hom M, A . The E evaluation map : G Βͺ G** is defined in the usual way and G is A-reflexive if G is an isomorphism. This is strongly related to the question of whether A is G slender as an E-module, and we discuss the p-groups for which this holds. In some important cases, G** can be viewed as the completion of G in a linear topology. It is known that if A s [ Z n, and G is a p-group of non-measurable cardinality, p n then G** can be identified with the completion of G in the [-topology, and we c provide a generalization of this result. We also show that for any group N of Ε½ . non-measurable cardinality there is a group G such that G**r G ( N.
π SIMILAR VOLUMES
when A is a torsion-free abelian group of rank one. As a consequence he was able to show that a finite rank torsion-free group M satisfies M ( nat M\*\* if and only if M F A I and pM s M precisely when pA s A, where Ε½ . M\*sHom y, A . Using this Warfield obtained a characterization of Z Ε½ . w x the
Semisimple tensor categories with fusion rules of self-duality for finite abelian groups are classified. As an application, we prove that the Tannaka duals of the dihedral and the quaternion groups of order 8 and the eight-dimensional Hopf algebra of Kac and Paljutkin are not isomorphic as abstract
## Abstract We give several constructions for invertible terraces and invertible directed terraces. These enable us to give the first known infinite families of invertible terrraces, both directed and undirected, for nonβabelian groups. In particular, we show that all generalized dicyclic groups of
Let b be the principal p-block of a finite group G with an abelian defect group Ε½ . Ε½ Ε½ . Ε½ .. P and e a root of b in C P . If the inertial quotient E s N P, e rPΠΈC P is G G G Ε½ . an elementary abelian 2-group respectively, a dihedral group of order 8 and Ε½ . p / 3, then b and its Brauer correspond