منابع مشابه
Relatively lifting modules
We consider a generalization of lifting modules relative to a class A of modules and a proper class E of short exact sequences of modules. These modules will be called E-A-lifting. We establish characterizations of modules with the property that every direct sum of copies of them is E-A-lifting. 2000 Mathematics Subject Classification: 16S90, 16D80.
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Let R be a ring, M a right R-module, and n a fixed non-negative integer. M is called n-cotorsion if Extn+1 R N M = 0 for any flat right R-module N . M is said to be n-flat if ExtR M N = 0 for any n-cotorsion right R-module N . We prove that ( n n is a complete hereditary cotorsion theory, where n (resp. n) denotes the class of all n-flat (resp. n-cotorsion) right R-modules. Several applications...
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We show that the quasiequational theory of a relatively congruence modular quasivariety of left R-modules is determined by a two-sided ideal in R together with a filter of left ideals. The two-sided ideal encodes the identities that hold in the quasivariety, while the filter of left ideals encodes the quasiidentities. The filter of left ideals defines a generalized notion of torsion. It follows...
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ژورنال
عنوان ژورنال: Bulletin of the Australian Mathematical Society
سال: 1975
ISSN: 0004-9727,1755-1633
DOI: 10.1017/s0004972700024631