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On Extending Projectives of Finite Group-Graded Algebras

Published online by Cambridge University Press:  20 November 2018

Morton E. Harris
Morton E. Harris*
Affiliation:
School of Mathematics University of Minnesota Minneapolis, Minnesota 55455
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Abstract

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Let G be a finite group, let k be a field and let R be a finite dimensional fully G-graded k-algebra. Also let L be a completely reducible R-module and let P be a projective cover of R. We give necessary and sufficient conditions for P|R1 to be a projective cover of L|R1 in Mod (R1). In particular, this happens if and only if L is R1-projective. Some consequences in finite group representation theory are deduced.

Keywords

16A0316A26.
Type
Research Article
Information
Canadian Mathematical Bulletin , Volume 34 , Issue 2 , 01 June 1991 , pp. 224 - 228
Copyright
Copyright © Canadian Mathematical Society 1991

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