| Using endomorphisms of modules in this paper, we give the characterizations for rings of weak global dimension ≤n where n≥0. Let R be a ring, we partially answer the question: When has any finitely presented R-module M the nonfinitely resolution: 0→M→F0→F1→…→Fn→…, where each Fi is finitely generated projective, i=0,1,2,…? |
