Help


from Wikipedia
« »  
* Any ring R can be considered as a one-object preadditive category ; the category of left modules over R is the same as the additive functor category Add ( R, Ab ) ( where Ab denotes the category of abelian groups ), and the category of right R-modules is Add ( R < sup > op </ sup >, Ab ).
Because of this example, for any preadditive category C, the category Add ( C, Ab ) is sometimes called the " category of left modules over C " and Add ( C < sup > op </ sup >, Ab ) is the category of right modules over C.

1.881 seconds.