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SOME REMARKS ON COTORSION ENVELOPES OF MODULES

  • Kim, Hae-Sik (DEPARTMENT OF MATHEMATICS KYUNGPOOK NATIONAL UNIVERSITY) ;
  • Song, Yeong-Moo (DEPARTMENT OF MATHEMATICS EDUCATION SUNCHON NATIONAL UNIVERSITY)
  • Published : 2007.11.30

Abstract

In this paper we prove that the extension of pure injective module is pure injective if and only if the cotorsion envelope and the pure injective envelope of any R-module M are isomorphic over M. And we prove that if the product of pure injective envelopes of flat modules is a pure injective envelope and the product of flat covers is a flat cover, then the product of cotorsion envelopes is a cotorsion envelope.

Keywords

flat cover;pure injective envelope;cotorsion envelope

References

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