Definition:Functor Creating Limits

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Definition

Let $\mathbf C, \mathbf D$ and $\mathbf J$ be metacategories.

Let $F: \mathbf C \to \mathbf D$ be a functor.


Then $F$ is said to create limits of type $\mathbf J$ if and only if:

For all $\mathbf J$-diagrams $C: \mathbf J \to \mathbf C$ in $\mathbf C$, given a limit $\paren {{\varprojlim \,}_j \, FC_j, q_j}$ for $FC: \mathbf J \to \mathbf D$ in $\mathbf D$, the limit:
$\paren {{\varprojlim \,}_j \, C_j, p_j}$
exists, and furthermore:
$\map F {{\varprojlim \,}_j \, C_j} = {\varprojlim \,}_j \, FC_j$
$F p_j = q_j$
for all objects $j$ of $\mathbf J$.


Also see


Sources