CatDat

category of metric spaces with ∞ allowed

  • notation: Met\mathbf{Met}_{\infty}
  • objects: metric spaces, where the metric is allowed to assume the value \infty
  • morphisms: non-expansive maps ff, meaning d(f(x),f(y))d(x,y)d(f(x),f(y)) \leq d(x,y) for all x,yx,y
  • nLab Link
  • Related categories: Met\mathbf{Met}Metc\mathbf{Met}_c

The fact that we allow \infty means that universal constructions work much better.

Properties

Properties from the database

Deduced properties

Non-Properties

Non-Properties from the database

Deduced Non-Properties*

*This also uses the deduced properties.

Unknown properties

Special morphisms

  • Isomorphisms: bijective isometries
  • Monomorphisms: injective non-expansive maps
  • Epimorphisms: