Vanishing of Ext and Tor over fiber products

S Nasseh, S Sather-Wagstaff - Proceedings of the American Mathematical …, 2017 - ams.org
Consider a non-trivial fiber product $ R= S\times _kT $ of local rings $ S $, $ T $ with
common residue field $ k $. Given two finitely generated $ R $-modules $ M $ and $ N $, we …

Algebras that satisfy Auslander's condition on vanishing of cohomology

LW Christensen, H Holm - Mathematische Zeitschrift, 2010 - Springer
Auslander conjectured that every Artin algebra satisfies a certain condition on vanishing of
cohomology of finitely generated modules. The failure of this conjecture—by a 2003 …

Persistence of homology over commutative noetherian rings

LL Avramov, SB Iyengar, S Nasseh, K Sather-Wagstaff - Journal of Algebra, 2022 - Elsevier
We describe new classes of noetherian local rings R whose finitely generated modules M
have the property that Tor i R (M, M)= 0 for i≫ 0 implies that M has finite projective …

Homology over trivial extensions of commutative DG algebras

LL Avramov, SB Iyengar, S Nasseh… - Communications in …, 2019 - Taylor & Francis
Conditions on the Koszul complex of a noetherian local ring R guarantee that Tor i R (M, N)
is nonzero for infinitely many i, when M and N are finitely generated R-modules of infinite …

Semidualizing Modules over Numerical Semigroup Rings

E Celikbas, H Geller, T Kobayashi - arXiv preprint arXiv:2306.14989, 2023 - arxiv.org
A semidualizing module is a generalization of Grothendieck's dualizing module. For a local
Cohen-Macaulay ring $ R $, the ring itself and its canonical module are always realized as …

Naïve liftings of DG modules

S Nasseh, M Ono, Y Yoshino - Mathematische Zeitschrift, 2022 - Springer
Let n be a positive integer, and let A be a strongly commutative differential graded (DG)
algebra over a commutative ring R. Assume that B= A [X 1,…, X n] is a polynomial extension …

Diagonal tensor algebra and naive liftings

S Nasseh, M Ono, Y Yoshino - arXiv preprint arXiv:2309.05293, 2023 - arxiv.org
The notion of naive lifting of DG modules was introduced by the authors in [16, 17] for the
purpose of studying problems in homological commutative algebra that involve self …

Ring homomorphisms and local rings with quasi-decomposable maximal ideal

S Nasseh, KA Sather-Wagstaff… - Communications in …, 2024 - Taylor & Francis
The notion of local rings with quasi-decomposable maximal ideal was formally introduced by
Nasseh and Takahashi. In separate works, the authors of the present paper showed that …

Some Homological Conjectures Over Idealization Rings

I Nascimento, V Jorge-Pérez, T Freitas - arXiv preprint arXiv:2405.06745, 2024 - arxiv.org
Let $(R,\mathfrak {m}, k) $ be a Noetherian local ring and let $ M $ be a finitely generated $
R $-module. The main focus of this paper is to give positive answers for some long-standing …

Finitistic extension degree

K Diveris - Algebras and Representation Theory, 2014 - Springer
We introduce the finitistic extension degree of a ring and investigate rings for which it is
finite. The Auslander–Reiten Conjecture is proved for rings of finite finitistic extension …