Geodesic
On Extending Projectives of Finite Group-Graded Algebras
Canadian mathematical bulletin, Tome 34 (1991) no. 2, pp. 224-228

Voir la notice de l'article provenant de la source Cambridge University Press

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|R 1 in Mod (R1). In particular, this happens if and only if L is R1-projective. Some consequences in finite group representation theory are deduced.
DOI : 10.4153/CMB-1991-036-9
Mots-clés : 16A03, 16A26. 
Harris, Morton E. On Extending Projectives of Finite Group-Graded Algebras. Canadian mathematical bulletin, Tome 34 (1991) no. 2, pp. 224-228. doi: 10.4153/CMB-1991-036-9
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