Let D be a division algebra of degree m over its center F. Herstein has shown Ε½ . that any finite normal subgroup of D\* [ GL D is central. Here, as a generaliza-1 tion of this result, it is shown that any finitely generated normal subgroup of D\* is Ε½ central. This also solves a problem raised by A
Free Subgroups in Maximal Subgroups of GL1(D)
β Scribed by M Mahdavi-Hezavehi
- Publisher
- Elsevier Science
- Year
- 2001
- Tongue
- English
- Weight
- 94 KB
- Volume
- 241
- Category
- Article
- ISSN
- 0021-8693
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β¦ Synopsis
Let D be a division algebra of finite dimension over its center F. Given a Ε½ . noncommutative maximal subgroup M of D* [ GL D , it is proved that either 1 M contains a noncyclic free subgroup or there exists a maximal subfield K of D Ε½ . which is Galois over F such that K * is normal in M and MrK * ( Gal KrF . Using this result, it is shown in particular that if D is a noncrossed product division algebra, then M does not satisfy any group identity.
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