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ON TOR-TORSION THEORIES

  • GOLRIZ M. (Science and Research Branch Islamic Azad University) ;
  • BIJANZADEH M. H. (Faculty of Mathematical Sciences and Computer Engineering Teacher Training University)
  • Published : 2005.04.01

Abstract

Tor-torsion theory was defined by Jan Trlifaj in 2000. In this paper we introduce the notion of Co envelopes, CoCovers and Tor-generators as dual of envelopes, covers and generators in cotorsion(Ext-torsion) theory and deduce that each R-module has a projective and a cotorsion coprecover.

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