category of partially ordered sets without isolated points

Notation Posnoiso\Pos_{\noiso} Objects partially ordered sets that have no isolated points Morphisms order-preserving functions Related Pos\Pos

Here, a point is called isolated if it is not comparable to any other point. Thus, we consider partially ordered sets whose connected components have cardinality 2\geq 2. This category provides an example of an infinitary extensive category that is not Cauchy complete.

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: empty poset
  • products: [non-empty case] direct products with the evident partial order
  • coproducts: disjoint union with the obvious partial order in which distinct summands are incomparable

Special morphisms

  • isomorphisms: bijective functions that are order-preserving and order-reflecting
  • monomorphisms: injective order-preserving functions
  • epimorphisms: surjective order-preserving functions
  • regular monomorphisms: embeddings
  • regular epimorphisms: