The Telescope Conjecture for Hereditary Rings via Ext-orthogonal Pairs
نویسندگان
چکیده
For the module category of a hereditary ring, the Ext-orthogonal pairs of subcategories are studied. For each Ext-orthogonal pair that is generated by a single module, a 5-term exact sequence is constructed. The pairs of finite type are characterized and two consequences for the class of hereditary rings are established: homological epimorphisms and universal localizations coincide, and the telescope conjecture for the derived category holds true.
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تاریخ انتشار 2008