Homological dimensions of complexes of R-modules

Document Type: Research Articles


1 دانشگاه آزاد واحد گچساران ایران

2 دانشگاه آزاد واحد گچساران


Let R be an associative ring with identity, C(R) be the category of com-
plexes of R-modules and Flat(C(R)) be the class of all at complexes of R-
modules. We show that the at cotorsion theory (Flat(C(R)); Flat(C(R)))
have enough injectives in C(R). As an application, we prove that for each at
complex F and each complex Y of R-modules, Exti (F,X)= 0, whenever R
is n-perfect and i > n.

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