We introduce the notion of a minimal extension of t-groups. Linear independence of the coordinates of the logarithm of an algebraic point in a minimal extension of t-groups follows naturally from linear independence of the coordinates of the image in the tangent space of the base t-group. We illustr
Independence of group algebras
โ Scribed by R. Conti; J. Hamhalter
- Publisher
- John Wiley and Sons
- Year
- 2010
- Tongue
- English
- Weight
- 152 KB
- Volume
- 283
- Category
- Article
- ISSN
- 0025-584X
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โฆ Synopsis
Abstract
It is shown that major independence conditions for left and right group operator algebras coincide. If ฮฃ is a discrete ICC group, then the reduced left and right group algebras W^*^~ฮป~(ฮฃ) and W~ฯฑ~^*^(ฮฃ) are W^*^โindependent. These algebras are moreover independent in the product sense if, and only if, ฮฃ is amenable. If A and B are subgroups of ฮฃ, then the left and right reduced group (sub)algebras W^*^~ฮป~(A) and W~ฯฑ~^*^(B) are W^*^โindependent provided that any of the following two conditions is satisfied: (i) A and B have trivial intersection; (ii) A or B is ICC. The results indicate an interplay between intrinsic groupโtheoretic properties and independence of the corresponding group algebras that can be further exploited. New examples of W^*^โindependent von Neumann algebras arising from groups are generated (ยฉ 2010 WILEYโVCH Verlag GmbH & Co. KGaA, Weinheim)
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