rings for which every simple module is almost injective
نویسندگان
چکیده
we introduce the class of “right almost v-rings” which is properly between the classes of right v-rings and right good rings. a ring r is called a right almost v-ring if every simple r-module is almost injective. it is proved that r is a right almost v-ring if and only if for every r-module m, any complement of every simple submodule of m is a direct summand. moreover, r is a right almost v-ring if and only if for every simple r-module s, either s is injective or the injective hull of s is projective of length 2. right artinian right almost v-rings and right noetherian right almost v-rings are characterized. a 2×2 upper triangular matrix ring over r is a right almost v-ring precisely when r is semisimple.
منابع مشابه
Rings for which every simple module is almost injective
We introduce the class of “right almost V-rings” which is properly between the classes of right V-rings and right good rings. A ring R is called a right almost V-ring if every simple R-module is almost injective. It is proved that R is a right almost V-ring if and only if for every R-module M, any complement of every simple submodule of M is a direct summand. Moreover, R is a right almost V-rin...
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عنوان ژورنال:
bulletin of the iranian mathematical societyناشر: iranian mathematical society (ims)
ISSN 1017-060X
دوره 42
شماره 1 2016
کلمات کلیدی
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