Metamath Proof Explorer


Definition df-cmd

Description: A co-cone (or cocone) to a diagram (see df-lmd for definition), or a natural sink for a diagram in a category C is a pair of an object X in C and a natural transformation from the diagram to the constant functor (or constant diagram) of the object X . The second component associates each object in the index category with a morphism in C whose codomain is X ( coccl ). The naturality guarantees that the combination of the diagram with the co-cone must commute ( coccom ). Definition 11.27(1) of Adamek p. 202.

A colimit of a diagram F : D --> C of type D in category C is a universal pair from the diagram to the diagonal functor ( C DiagFunc D ) . The universal pair is a co-cone to the diagram satisfying the universal property, that each co-cone to the diagram uniquely factors through the colimit. ( iscmd ). Definition 11.27(2) of Adamek p. 202.

Initial objects, coproducts, coequalizers, pushouts, and direct limits can be considered as colimits of some diagram; colimits can be further generalized as left Kan extensions ( df-lan ).

"cmd" is short for "colimit of a diagram". See df-lmd for the dual concept. (Contributed by Zhi Wang, 12-Nov-2025)

Ref Expression
Assertion df-cmd Could not format assertion : No typesetting found for |- Colimit = ( c e. _V , d e. _V |-> ( f e. ( d Func c ) |-> ( ( c DiagFunc d ) ( c UP ( d FuncCat c ) ) f ) ) ) with typecode |-

Detailed syntax breakdown

Step Hyp Ref Expression
0 ccmd Could not format Colimit : No typesetting found for class Colimit with typecode class
1 vc setvar c
2 cvv class V
3 vd setvar d
4 vf setvar f
5 3 cv setvar d
6 cfunc class Func
7 1 cv setvar c
8 5 7 6 co class d Func c
9 cdiag class Δ func
10 7 5 9 co class c Δ func d
11 cup Could not format UP : No typesetting found for class UP with typecode class
12 cfuc class FuncCat
13 5 7 12 co class d FuncCat c
14 7 13 11 co Could not format ( c UP ( d FuncCat c ) ) : No typesetting found for class ( c UP ( d FuncCat c ) ) with typecode class
15 4 cv setvar f
16 10 15 14 co Could not format ( ( c DiagFunc d ) ( c UP ( d FuncCat c ) ) f ) : No typesetting found for class ( ( c DiagFunc d ) ( c UP ( d FuncCat c ) ) f ) with typecode class
17 4 8 16 cmpt Could not format ( f e. ( d Func c ) |-> ( ( c DiagFunc d ) ( c UP ( d FuncCat c ) ) f ) ) : No typesetting found for class ( f e. ( d Func c ) |-> ( ( c DiagFunc d ) ( c UP ( d FuncCat c ) ) f ) ) with typecode class
18 1 3 2 2 17 cmpo Could not format ( c e. _V , d e. _V |-> ( f e. ( d Func c ) |-> ( ( c DiagFunc d ) ( c UP ( d FuncCat c ) ) f ) ) ) : No typesetting found for class ( c e. _V , d e. _V |-> ( f e. ( d Func c ) |-> ( ( c DiagFunc d ) ( c UP ( d FuncCat c ) ) f ) ) ) with typecode class
19 0 18 wceq Could not format Colimit = ( c e. _V , d e. _V |-> ( f e. ( d Func c ) |-> ( ( c DiagFunc d ) ( c UP ( d FuncCat c ) ) f ) ) ) : No typesetting found for wff Colimit = ( c e. _V , d e. _V |-> ( f e. ( d Func c ) |-> ( ( c DiagFunc d ) ( c UP ( d FuncCat c ) ) f ) ) ) with typecode wff