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Division Algebras Not Embeddable in Crossed Products

✍ Scribed by Eric S. Brussel


Publisher
Elsevier Science
Year
1996
Tongue
English
Weight
317 KB
Volume
179
Category
Article
ISSN
0021-8693

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✦ Synopsis


We show that division algebras do not always embed in crossed product division algebras, so the latter do not serve as ''Galois closures'' for division algebras. We construct decomposable noncrossed product division algebras of prime-power index over rational function fields and Laurent series fields over number fields. We discover a rigid nonabelian group of order p 4 .


πŸ“œ SIMILAR VOLUMES


Embedding Division Algebras in Crossed P
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Let F be an arbitrary field and let D be a division algebra having center F which is finite dimensional over F. In general, there need not exist a maximal subfield E of D which is Galois over F. If such an E exists, we Ε½ call D a crossed product or G G-crossed product if G G is the Galois group of .

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