On Flatness and Projectivity of a Ring as a Module over a Fixed Subring.
نویسندگان
چکیده
منابع مشابه
Projectivity and flatness over the endomorphism ring of a finitely generated module
Let A be a ring, and Λ a finitely generated A-module. We give necessary and sufficient conditions for projectivity and flatness of a module over the endomorphism ring of Λ.
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Let k be a field, G an abelian group with a bicharacter, A a colour algebra; i.e., an associative graded k-algebra with identity, C a graded A-coring that is projective as a right A-module, C∗ the graded dual ring of C and Λ a left graded C-comodule that is finitely generated as a graded right C∗-module. We give necessary and sufficient conditions for projectivity and flatness of a graded modul...
متن کاملProjectivity and Flatness over the Endomorphism Ring of a Finitely Generated Comodule
Let k be a commutative ring, A a k-algebra, C an A-coring that is projective as a left A-module, ∗C the dual ring of C and Λ a right C-comodule that is finitely generated as a left ∗C-module. We give necessary and sufficient conditions for projectivity and flatness of a module over the endomorphism ring EndC(Λ). If C contains a grouplike element, we can replace Λ with A.
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ژورنال
عنوان ژورنال: MATHEMATICA SCANDINAVICA
سال: 1995
ISSN: 1903-1807,0025-5521
DOI: 10.7146/math.scand.a-12533