sequential limits
A category has sequential limits if it has limits of diagrams of the following form:
- Dual property: sequential colimits
- Related properties: filtered limits
- nLab Link
Relevant implications
equalizers and countable products implies sequential limits
Mac Lane, V.2, Prop. 3. The proof can easily be adapted to this case. Namely, the limit of is the equalizer of two suitable endomorphisms of .finite products and sequential limits implies countable products
If is an infinite sequence of objects, then their product is the limit of the sequence .filtered limits implies sequential limits
trivialself-dual and sequential limits implies sequential colimits
trivial by self-dualityself-dual and sequential colimits implies sequential limits
trivial by self-duality
Examples
- category of abelian groups
- category of Banach spaces with linear contractions
- category of commutative rings
- category of fields
- category of finite sets and bijections
- category of finite sets and injections
- category of groups
- category of left R-modules
- category of locally ringed spaces
- category of M-sets
- category of measurable spaces
- category of metric spaces with ∞ allowed
- category of metric spaces with continuous maps
- category of monoids
- category of pointed sets
- category of posets
- category of rings
- category of rngs
- category of sets
- category of simplicial sets
- category of small categories
- category of topological spaces
- category of vector spaces
- category of Z-functors
- delooping of a non-trivial finite group
- delooping of an infinite group
- discrete category on two objects
- empty category
- partial order [0,1]
- partial order of extended natural numbers
- partial order of natural numbers
- partial order of ordinal numbers
- preorder of integers w.r.t. divisiblity
- trivial category
- walking isomorphism
- walking morphism
- walking parallel pair of morphisms
Counterexamples
- category of combinatorial species
- category of finite abelian groups
- category of finite orders
- category of finite sets
- category of finite sets and surjections
- category of finitely generated abelian groups
- category of free abelian groups
- category of metric spaces with non-expansive maps
- category of non-empty sets
- category of schemes
- category of smooth manifolds
- delooping of the additive monoid of natural numbers
Unknown
For these categories the database has no info if they satisfy this property or not.