Exact subcategories, subfunctors of $\mathrm{Ext}$, and some applications

Hailong Dao, Souvik Dey, Monalisa Dutta

Let $(\mathcal{A},\mathcal{E})$ be an exact category. We establish basic results that allow one to identify sub(bi)functors of ${\mathrm{Ext}}_{\mathcal{E}}(-,-)$ using additiv…