On the isomorphic classes of Hopf-Galois extensions with normal bases overa commutative ring

Authors
Jiang, XL Xu, YH
Citation
Xl. Jiang et Yh. Xu, On the isomorphic classes of Hopf-Galois extensions with normal bases overa commutative ring, ACTA MATH S, 15(4), 1999, pp. 515-524
Citations number
10
Categorie Soggetti
Mathematics
Journal title
ACTA MATHEMATICA SINICA-ENGLISH SERIES
ISSN journal
10009574 → ACNP
Volume
15
Issue
4
Year of publication
1999
Pages
515 - 524
Database
ISI
SICI code
1000-9574(199910)15:4<515:OTICOH>2.0.ZU;2-A
Abstract
In this paper we consider the isomorphic classes of H-Galois extensions wit h the normal basis property over a fixed commutative ring B for a finite Ho pf algebra H. The result is that when H is cocommutative, then the above is omorphic classes and the 2-nd cohomology group H-2 (L*, U) are isomorphic a s groups under the product defined in this paper, where L = B circle times H, L* = Hom(B) (L, B).