CatDat

dual of the category of sets

  • notation: Setop\mathbf{Set}^{\mathrm{op}}
  • objects: sets
  • morphisms: A morphism f:XYf : X \to Y is a map of sets YXY \to X.
  • nLab Link
  • Dual category: Set\mathbf{Set}

By definition, this category is the dual (or opposite) of the category of sets.

Satisfied Properties

Properties from the database

Deduced properties

Unsatisfied Properties

Properties from the database

Deduced properties*

*This also uses the deduced satisfied properties.

Unknown properties

There is 1 property for which the database doesn't have an answer if it is satisfied or not. Please help to contribute the data!

Special objects

  • terminal object: empty set
  • initial object: singleton set
  • products: disjoint union
  • coproducts: direct products with pointwise operations

Special morphisms

  • isomorphisms: bijective maps
  • monomorphisms: surjective maps
  • epimorphisms: injective maps
  • regular monomorphisms: surjective homomorphisms
  • regular epimorphisms: same as monomorphisms