Homotopy Type Theory
weak equivalence of precategories (Rev #1)

Idea

Definition

A functor F:ABF: A \to B is essentially surjective if for all b:Bb:B, there merely exists an a:Aa:A such that FabF a \cong b.

We say that FF is a weak equivalence if it is fully faithful and essentially surjective.

For categories there is no difference between weak equivalences and equivalences.

Properties

See also

Category theory equivalence of precategories functor fully faithful functor

References

HoTT book

Revision on September 19, 2018 at 17:30:57 by Ali Caglayan. See the history of this page for a list of all contributions to it.