Given a finite-dimensional algebra, we present sufficient conditions on the projective presentation of the algebra modulo its radical for a tilted algebra to be a Koszul algebra and for the endomorphism ring of a tilting module to be a quasi-Koszul algebra. One condition we impose is that the algebra has global dimension no greater than 2. One of the main techniques is studying maps between the direct summands of the tilting module. Some applications are given. We also show that a Brenner-Butler tilted algebra is simply connected if and only if the original algebra is simply connected.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-cm92-2-5,
author = {R. M. Aquino and E. L. Green and E. N. Marcos},
title = {Koszul and quasi-Koszul algebras obtained by tilting},
journal = {Colloquium Mathematicae},
volume = {91},
year = {2002},
pages = {197-224},
zbl = {1018.16017},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-cm92-2-5}
}
R. M. Aquino; E. L. Green; E. N. Marcos. Koszul and quasi-Koszul algebras obtained by tilting. Colloquium Mathematicae, Tome 91 (2002) pp. 197-224. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-cm92-2-5/