nLab concrete (2,1)-category

Contents

Context

2-Category theory

Higher category theory

higher category theory

Basic concepts

Basic theorems

Applications

Models

Morphisms

Functors

Universal constructions

Extra properties and structure

1-categorical presentations

Discrete and concrete objects

Contents

Idea

A generalization of the notion of concrete category from category theory to (2,1)-category theory.

 Definition

Definition

A concrete (2,1)-category is a (2,1)-category CC equipped with a 3-surjective functor

U:CGrpd U \colon C \to Grpd

to the large (2,1)-category Grpd of groupoids. We say a (2,1)-category CC is concretizable if and only if it admits a 3-surjective functor U:CGrpdU \colon C \to Grpd.

Examples

Last revised on May 18, 2022 at 16:36:35. See the history of this page for a list of all contributions to it.