On Galois algebras satisfying the fundamental theorem

被引:3
作者
Szeto, George [1 ]
Xue, Lianyong [1 ]
机构
[1] Bradley Univ, Dept Math, Peoria, IL 61625 USA
关键词
Azumaya algebras; central Galois algebras; Galois algebras; Galois extensions; separable extensions;
D O I
10.1080/00927870701509529
中图分类号
O1 [数学];
学科分类号
0701 ; 070101 ;
摘要
Let B be a Galois algebra over a commutative ring R with Galois group G such that B-H is a separable subalgebra of B for each subgroup H of G. Then it is shown that B satisfies the fundamental theorem if and only if B is one of the following three types: (1) B is an indecomposable commutative Galois algebra, (2) B = Re circle plus R(1 - e) where e and I - e are minimal central idempotents in B, and (3) B is an indecomposable Galois algebra such that for each separable subalgebra A, V-B (A) = circle plus Sigma(g is an element of G(A)) J(g), and the centers of A and B-G(A) are the same where V-B(A) is the commutator subring of A in B, J(g) = {b is an element of B / bx = g(x)b for each X is an element of B) for a g is an element of G, and G(A) = {g is an element of G / g(a) = a for all a is an element of A}.
引用
收藏
页码:3979 / 3985
页数:7
相关论文
共 9 条
[1]  
CHASE SU, 1965, MEMOIRS AM MATH, V52
[2]  
DeMeyer F. R., 1971, SEPARABLE ALGEBRAS O, V181
[3]   GALOIS THEORY IN SEPARABLE ALGEBRAS OVER COMMUTATIVE RINGS [J].
DEMEYER, FR .
ILLINOIS JOURNAL OF MATHEMATICS, 1966, 10 (02) :287-&
[4]  
DEMEYER FR, 1965, OSAKA J MATH, V2, P117
[5]  
Kanzaki T., 1965, Osaka J. Math., V2, P309
[6]  
Rosenberg A., 1961, Pacific J. Math., V11, P1109
[7]  
Sugano K., 1980, Hokkaido Math. J., V9, P123
[8]   The Galois algebra with Galois group which is the automorphism group [J].
Szeto, G ;
Xue, LY .
JOURNAL OF ALGEBRA, 2005, 293 (01) :312-318
[9]   The structure of Galois algebras [J].
Szeto, G ;
Xue, LY .
JOURNAL OF ALGEBRA, 2001, 237 (01) :238-246