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Twisted group rings and a problem of Faith

Published online by Cambridge University Press:  17 April 2009

John H. Cozzens
Affiliation:
Columbia University, New York, New York, USA Department of Mathematics, Rider College, Lawrenceville, New Jersey, USA.
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Abstract

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A homological characterization is given of when a twisted group ring relative to an automorphism of an arbitrary field has all of its simple right modules injective (= a right V-ring). This answers a question raised by Osofsky. A “Hilbert Theorem 90” type theorem determines the cardinality of the isomorphism classes of one-dimensional simple modules.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1973

References

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