A variant theory for the Gorenstein flat dimension

• Autorzy: Samir Bouchiba
• Języki publikacji: EN

Abstrakty

EN

This paper discusses a variant theory for the Gorenstein flat dimension. Actually, since it is not yet known whether the category 𝓖𝓕(R) of Gorenstein flat modules over a ring R is projectively resolving or not, it appears legitimate to seek alternate ways of measuring the Gorenstein flat dimension of modules which coincide with the usual one in the case where 𝓖𝓕(R) is projectively resolving, on the one hand, and present nice behavior for an arbitrary ring R, on the other. In this paper, we introduce and study one of these candidates called the generalized Gorenstein flat dimension of a module M and denoted by $GGfd_{R}(M)$ via considering exact sequences of modules of finite flat dimension. The new entity stems naturally from the very definition of Gorenstein flat modules. It turns out that the generalized Gorenstein flat dimension enjoys nice behavior in the general setting. First, for each R-module M, we prove that $GGfd_{R}(M) = Gid_{R}(Hom_{ℤ} (M,ℚ /ℤ))$ whenever $GGf_{R}(M)$ is finite. Also, we show that 𝓖𝓕(R) is projectively resolving if and only if the Gorenstein flat dimension and the generalized Gorenstein flat dimension coincide. In particular, if R is a right coherent ring, then $GGfd_{R}(M) = Gfd_{R}(M)$ for any R-module M. Moreover, the global dimension associated to the generalized Gorenstein flat dimension, called the generalized Gorenstein weak global dimension and denoted by GG-wgldim(R), turns out to be the best counterpart of the classical weak global dimension in Gorenstein homological algebra. In fact, it is left-right symmetric and it is related to the cohomological invariants r-sfli(R) and l-sfli(R) by the formula
GG-wgldim(R) = max{r-sfli(R),l-sfli(R)}.

Kategorie tematyczne

• 13D02: Syzygies, resolutions, complexes
• 16E10: Homological dimension
• 13D05: Homological dimension
• 13D07: Homological functors on modules (Tor, Ext, etc.)
• 16E05: Syzygies, resolutions, complexes

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Colloquium Mathematicum
• Rocznik: 2015
• Tom: 140
• Numer: 2
• Strony: 183-204

Daty

wydano

2015

Twórcy

autor

Samir Bouchiba

• Department of Mathematics, Faculty of Sciences, University Moulay Ismail, Meknes, Morocco

Identyfikatory

DOI

10.4064/cm140-2-3