Homological Dimensions in Cotorsion Pairs

Lidia Angeleri Hugel, Octavio Mendoza Hernandez

Two classes $\mathcal{A}$ and $\mathcal{B}$ of modules over a ring $R$ are said to form a cotorsion pair $(\mathcal{A},\mathcal{B})$ if $\mathcal{A}={\mathrm{KerExt}}_R^1(-,\mathcal{B})$ an…