PlanetPhysics/R Category
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R-category definition
editAn -category is a \htmladdnormallink{category {http://planetphysics.us/encyclopedia/Cod.html} equipped with an -module structure on each hom set such that the composition is -bilinear}. More precisely, let us assume for instance that we are given a commutative ring with identity. Then a small -category--or equivalently an -algebroid -- will be defined as a category enriched in the monoidal category of -modules, with respect to the monoidal structure of tensor product. This means simply that for all objects of , the set is given the structure of an -module, and composition Failed to parse (unknown function "\lra"): {\displaystyle A(b,c) \times A(c,d) \lra A(b,d)} is --bilinear, or is a morphism of -modules Failed to parse (unknown function "\lra"): {\displaystyle A(b,c) \otimes_R A(c,d) \lra A(b,d)} .