On covers and envelopes in some functor categories

L Mao - Communications in Algebra, 2013 - Taylor & Francis
L Mao
Communications in Algebra, 2013Taylor & Francis
We study the existence of covers and envelopes by some special functors on the category of
finitely presented modules. As an application, we characterize some important rings using
these functors. We also investigate homological properties of some functors on the stable
module category. The relationship between phantoms and Ext-phantoms is obtained. It is
shown that every left R-module M has an Ext-phantom preenvelope f: M→ N with coker (f)
pure-projective. Finally, we prove that, as a torsionfree class of (mod-R, Ab),(mod-R, Ab) is …
We study the existence of covers and envelopes by some special functors on the category of finitely presented modules. As an application, we characterize some important rings using these functors. We also investigate homological properties of some functors on the stable module category. The relationship between phantoms and Ext-phantoms is obtained. It is shown that every left R-module M has an Ext-phantom preenvelope f: M → N with coker(f) pure-projective. Finally, we prove that, as a torsionfree class of (mod-R, Ab), (mod-R, Ab) is generated by the FP-injective objects.
Taylor & Francis Online
以上显示的是最相近的搜索结果。 查看全部搜索结果