PlanetPhysics/Grothendieck's Theorem

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\begin{theorem} {\mathbf Grothendieck's theorem}: Every $$\mathcal{A}b5$$ category with a generator has an injective cogenerator (Grothendieck 1957). \end{theorem}

This initial statement of Grothendieck's theorem is now restated as: \begin{theorem} Every Grothendieck category $$\mathcal{G}$$ has an injective cogenerator. \end{theorem}