Structure

multi-algebraic

A category is multi-algebraic if it satisfies one of the following equivalent conditions:
  1. It is a multi-cocomplete generalized variety, that is, it has multi-colimits, sifted colimits, and there is an essentially small collection GG of strongly finitely presentable objects such that every object is a sifted colimit of objects from GG.
  2. It is equivalent to the category of models of a small (finite product, coproduct)-sketch, or small FPC-sketch for short.
  3. It is equivalent to the category of multi-finite-product-preserving functors to Set\Set from a small category with multi-finite-products (multi-algebraic theory). Here, multi-finite-products means multi-limits of finite discrete diagrams.
  4. It is equivalent to the category of models of a small multi-finite-product sketch.
Multi-algebraic categories are like locally strongly finitely presentable categories but only with multi-colimits. The relation is similar to that between locally finitely multi-presentable and locally finitely presentable categories. For the equivalence of the conditions above, see Adámek–Rosický, Lem. 1 and Adámek–Rosický, Thm. 4.4. This notion was originally introduced by Diers.

Relevant implications

Examples

There are 41 categories with this property.

Counterexamples

There are 92 categories without this property.

Unknown

There are 2 categories for which the database has no information on whether they satisfy this property. Please help us fill in the gaps by contributing to this project.