simplex category

Notation Δ\Delta Objects the non-empty ordered sets [n]{0<<n}[n] \coloneqq \{0 < \cdots < n\} for nNn \in \IN Morphisms order-preserving maps Related FinOrd\FinOrdSet\SetnesSet\sSetΔ1\Delta^{\leq 1} External nLab Link

The simplex category is a skeleton of FinOrd{}\FinOrd \setminus \{\varnothing\}. It plays an important role in topology and is used to define the category of simplicial sets.

Satisfied Properties

Assigned properties

Deduced properties

Unsatisfied Properties

Assigned properties

Deduced properties*

*This also uses the deduced satisfied properties.

Unknown properties

Special objects

Special morphisms

  • isomorphisms: bijective order-preserving maps
  • monomorphisms: injective order-preserving maps
  • epimorphisms: surjective order-preserving maps
  • regular monomorphisms: same as monomorphisms
  • regular epimorphisms: same as epimorphisms