Let R$R$ be a non-Noetherian ring. Is its left global dimension lD(R) = sup { id(M) | M is a cyclic R-module${\rm{lD}}(R)$ equal to }$\sup \{ {\rm{id}}(M) \mid M \text{ is a cyclic $R$-module} \}$? id(M)Here $\rm{{id}}(M)$ denotes the injective dimension of R$M$.
Dag Oskar Madsen
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