essentially retractable modules
نویسندگان
چکیده
we call a module essentially retractable if homr for all essential submodules n of m. for a right fbn ring r, it is shown that: (i) a non-zero module is retractable (in the sense that homr for all non-zero ) if and only if certain factor modules of m are essentially retractable nonsingular modules over r modulo their annihilators. (ii) a non-zero module is essentially retractable if and only if there exists a prime ideal such that homr. over semiprime right nonsingular rings, a nonsingular essentially retractable module is precisely a module with non-zero dual. moreover, over certain rings r, including right fbn rings, it is shown that a nonsingular module m with enough uniforms is essentially retractable if and only if there exist uniform retractable r-modules and r-homomorphisms with .
منابع مشابه
Essentially Retractable Modules
We call a module essentially retractable if HomR for all essential submodules N of M. For a right FBN ring R, it is shown that: (i) A non-zero module is retractable (in the sense that HomR for all non-zero ) if and only if certain factor modules of M are essentially retractable nonsingular modules over R modulo their annihilators. (ii) A non-zero module is essentially retractable if and on...
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متن کاملApplications of Epi-Retractable and Co-Epi-Retractable Modules
A module M is called epi-retractable if every submodule of M is a homomorphic image of M. Dually, a module M is called co-epi-retractable if it contains a copy of each of its factor modules. In special case, a ring R is called co-pli (resp. co-pri) if RR (resp. RR) is co-epi-retractable. It is proved that if R is a left principal right duo ring, then every left ideal of R is an epi-retractable ...
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عنوان ژورنال:
journal of sciences, islamic republic of iranناشر: university of tehran
ISSN 1016-1104
دوره 18
شماره 4 2007
کلمات کلیدی
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