IJPAM: Volume 39, No. 4 (2007)

ON A COMPOSITION OF GALOIS EXTENSIONS

George Szeto$^1$, Lianyong Xue$^2$
$^{1,2}$Department of Mathematics
Bradley University
1501 West Bradley Avenue, Peoria, Illinois, 61625, USA
$^1$e-mail: [email protected]
$^2$e-mail: [email protected]


Abstract.Let $B$ be a Galois extension of $B^G$ with Galois group $G$ such that $B^G$ is a separable $C^G$-algebra, where $C$ is the center of $B$. Then an equivalent condition is given for $B$ as a composition of a Hirata Galois extension $B$ of $B^GC$ with Galois group $K$ and a DeMeyer-Kanzaki Galois extension $B^GC$ of $B^G$ with Galois group $G/K$, where $K=\{g\in G\,\vert\,g(c)=c$ for all $c\in C\}$. Properties of separable subextensions are also given.

Received: July 28, 2007

AMS Subject Classification: 16S35, 16W20

Key Words and Phrases: separable extensions, Galois extensions, Hirata separable extensions, Hirata Galois extensions, DeMeyer-Kanzaki Galois extensions

Source: International Journal of Pure and Applied Mathematics
ISSN: 1311-8080
Year: 2007
Volume: 39
Issue: 4