Category

Projective object

Let 𝖒 be a category. An object 𝑃 βˆˆπ–’ is said to be projective iff it has the following (left) lifting property against epimorphisms: For any morphism 𝑓 :𝑃 →𝐡 and epimorphism π‘ž :𝐴 ↠𝐡, there exists a factorization ¯𝑓 :𝑃 →𝐴 so that π‘žΒ―π‘“ =𝑓. cat

A quiver diagram.

Equivalently, the covariant hom-functor 𝖒(𝑃, βˆ’) preserves epimorphisms.

See also


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