Covering functors without groups
نویسندگان
چکیده
Coverings in the representation theory of algebras were introduced for the Auslander-Reiten quiver of a representation finite algebra in [15] and later for finite dimensional algebras in [2, 7, 11]. The best understood class of covering functors is that of Galois covering functors F : A → B determined by the action of a group of automorphisms of A. In this work we introduce the balanced covering functors which include the Galois class and for which classical Galois covering-type results still hold. For instance, if F : A → B is a balanced covering functor, where A and B are linear categories over an algebraically closed field, and B is tame, then A is tame.
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