Contravariantly finite subcategories and irreducible maps

Carlson, Jon F.; Happel, Dieter

doi:10.1090/S0002-9939-1993-1107270-1

Contravariantly finite subcategories and irreducible maps
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by Jon F. Carlson and Dieter Happel PDF

Proc. Amer. Math. Soc. 117 (1993), 61-65 Request permission

Abstract:

Let $\Lambda$ be an Artin algebra. This paper presents a condition that is necessary for a subcategory of $\bmod \Lambda$ to be contravariantly finite. Several examples are explored in the case that $\Lambda$ is the group algebra of a finite group over a field of finite characteristic.

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