Characterization of rings using quasiprojective modules. III

Golan, Jonathan S.

doi:10.1090/S0002-9939-1972-0302700-3

Characterization of rings using quasiprojective modules. III
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by Jonathan S. Golan PDF

Proc. Amer. Math. Soc. 31 (1972), 401-408 Request permission

Abstract:

A ring $R$ is regular [completely reducible] if and only if the character module of every left $R$-module is quasi-injective [quasiprojective]. Submodules of quasiprojective left $R$-modules over a left perfect ring $R$ are quasiprojective if and only if singular left $R$-modules are injective. A splitting theorem for right perfect rings over which submodules of quasiprojective left $R$-modules are quasiprojective is also proven. These results continue the author’s previous work ([5] and [6]).

References

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