We prove that an associated graded algebra $R_G$ of a finite dimensional algebra $R$ is $QF$ (= selfinjective) if and only if $R$ is $QF$ and Loewy coincident. Here $R$ is said to be Loewy coincident if, for every primitive idempotent $e$, the upper Loewy series and the lower Loewy series of $Re$ and $eR$ coincide. \endgraf $QF$-3 algebras are an important generalization of $QF$ algebras; note that Auslander algebras form a special class of these algebras. We prove that for a Loewy coincident algebra $R$, the associated graded algebra $R_G$ is $QF$-3 if and only if $R$ is $QF$-3.
We prove that an associated graded algebra $R_G$ of a finite dimensional algebra $R$ is $QF$ (= selfinjective) if and only if $R$ is $QF$ and Loewy coincident. Here $R$ is said to be Loewy coincident if, for every primitive idempotent $e$, the upper Loewy series and the lower Loewy series of $Re$ and $eR$ coincide. \endgraf $QF$-3 algebras are an important generalization of $QF$ algebras; note that Auslander algebras form a special class of these algebras. We prove that for a Loewy coincident algebra $R$, the associated graded algebra $R_G$ is $QF$-3 if and only if $R$ is $QF$-3.
@article{CMJ_2009_59_3_a1,
author = {Tachikawa, Hiroyuki},
title = {Loewy coincident algebra and $QF$-3 associated graded algebra},
journal = {Czechoslovak Mathematical Journal},
pages = {583--589},
year = {2009},
volume = {59},
number = {3},
mrnumber = {2545641},
zbl = {1224.13007},
language = {en},
url = {http://geodesic.mathdoc.fr/item/CMJ_2009_59_3_a1/}
}
TY - JOUR
AU - Tachikawa, Hiroyuki
TI - Loewy coincident algebra and $QF$-3 associated graded algebra
JO - Czechoslovak Mathematical Journal
PY - 2009
SP - 583
EP - 589
VL - 59
IS - 3
UR - http://geodesic.mathdoc.fr/item/CMJ_2009_59_3_a1/
LA - en
ID - CMJ_2009_59_3_a1
ER -
[1] Auslander, M.: Representation dimension of Artin algebras. Queen Mary College Lecture Notes (1971). | Zbl
[2] Morita, K.: Duality for modules and its applications to the theory of rings with minimum condition. Sci. Rep. Tokyo Kyoiku Daigaku, Sect. A. No. 150 (1958), 1-60. | MR | Zbl
[3] Nakayama, T.: On Frobeniusean algebras. II, Ann. Math. 42 (1941), 1-21. | DOI | MR | Zbl