Dimension projective finie et cohomologie locale
We present an alternative way of measuring the Gorenstein projective (resp., injective) dimension of modules via a new type of complete projective (resp., injective) resolutions. As an application, we easily recover well known theorems such as the Auslander-Bridger formula. Our approach allows us to relate the Gorenstein global dimension of a ring R to the cohomological invariants silp(R) and spli(R) introduced by Gedrich and Gruenberg by proving that leftG-gldim(R) = maxleftsilp(R), leftspli(R),...
Let and be two ring homomorphisms and let and be ideals of and , respectively, such that . In this paper, we investigate the transfer of the notions of Gaussian and Prüfer rings to the bi-amalgamation of with along with respect to (denoted by introduced and studied by S. Kabbaj, K. Louartiti and M. Tamekkante in 2013. Our results recover well known results on amalgamations in C. A. Finocchiaro (2014) and generate new original examples of rings possessing these properties.
We study the G-dimension over local ring homomorphisms with respect to a semi-dualizing complex. Some results that track the behavior of Gorenstein properties over local ring homomorphisms under composition and decomposition are given. As an application, we characterize a dualizing complex for in terms of the finiteness of the G-dimension over local ring homomorphisms with respect to a semi-dualizing complex.
Let be a ring extension of . We show the left -module with the endmorphism ring End is a generalized tilting module when is a generalized tilting module under some conditions.
Let be a commutative Noetherian ring. It is shown that the finitely generated -module with finite Gorenstein dimension is reflexive if and only if is reflexive for with , and for with . This gives a generalization of Serre and Samuel’s results on reflexive modules over a regular local ring and a generalization of a recent result due to Belshoff. In addition, for we give a characterization of -Gorenstein rings via Gorenstein dimension of the dual of modules. Finally it is shown...