CatDat

walking fork

  • Notation: Fork\Fork
  • Objects: three objects 0,1,20,1,2
  • Morphisms: one morphism i:01i : 0 \to 1, two morphisms f,g:12f,g : 1 \rightrightarrows 2, one morphism 020 \to 2 (namely, fi=gif \circ i = g \circ i), and the identities
  • Related categories: ForkSquare\ForkSquareSquare\SquareComp\CompPair\Pair

This category can be pictured as: {012}\{0 \to 1 \rightrightarrows 2\} Its name comes from the fact that a functor ForkC\Fork \to \C is the same as a fork in C\C. It can also be realized as the category of ordered sets of cardinality 2\leq 2 with injective order-preserving maps.

Satisfied Properties

Assigned properties

Deduced properties

Unsatisfied Properties

Assigned properties

Deduced properties*

*This also uses the deduced satisfied properties.

Unknown properties

Special objects

  • initial object: 00

Special morphisms

  • isomorphisms: only the identities
  • monomorphisms: every morphism
  • epimorphisms: the identities and f,gf,g
  • regular monomorphisms: the identities and ii
  • regular epimorphisms: same as isomorphisms

Morphisms

The database stores 1 morphism based on the walking fork.