PlanetPhysics/Preadditive Functor

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 A functor between two preadditive categories Failed to parse (unknown function "\A"): {\displaystyle \mathcal{\A_P}}
 and Failed to parse (unknown function "\A"): {\displaystyle \mathcal{\A'_P}}
 is called a (pre) additive (or preadditive) functor ,

if for any pair of morphisms Failed to parse (unknown function "\A"): {\displaystyle f, g \in Hom_{\mathcal{\A_P}}(X,Y)} one has that $F(f+g)=F(f)+F(g)$.