0 M ay 2 00 6 Construction of Koszul algebras by finite Galois covering ∗
نویسنده
چکیده
It is shown that Morita equivalence preserves quasi-Koszulity, and a finite-dimensional K-algebra A is quasi-Koszul if and only if the skew group algebra A * G is, where G is a finite group satisfying charK ∤ |G|. It follows from these results that a finite-dimensional K-algebra A is quasi-Koszul if and only if the smash product A#G * is, where G is a finite group satisfying charK ∤ |G|. Furthermore, it is proved that a finite-dimensional quiver algebra is Koszul if and only if its finite Galois covering algebra with Galois group G satisfying charK ∤ |G| is, which provides the construction of Koszul algebras by finite Galois covering.
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