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Regular skew group rings

Published online by Cambridge University Press:  09 April 2009

Ricardo Alfaro
Affiliation:
Department of Mathematics, University of Michigan-Flint, Flint, MI 48502, U.S.A.
Pere Ara
Affiliation:
Department de Matemàtiques, Universitat Autònoma de Barcelona, (08193) Bellaterra (Barcelona), Spain
Angel Del Río
Affiliation:
Department de Matemàtiqus, Universidad de Murcia, (30001) Murcia, Spain
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Abstract

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Let G be a group acting on a ring R. We study the problem of determining necessary and sufficient conditions in order that the skew group ring RG be von Neumann regular. Complete characterizations are given in some particular situations, including the case where all idempotents of R are central. For a regular ring R admitting a G-invariant pseudo-rank function N, with G finite, we obtain a necessary condition for RG being regular in terms of the induced action of G on the N-completion of R.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1995

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