walking span
- notation:
- objects:
- morphisms: , , and the identities
- Related categories: ,
- nLab Link
The name of this category comes from the fact that a functor out of it is the same as a span in the target category. It is isomorphic to the partial order of proper positive divisors of .
Satisfied Properties
Assigned properties
- is small
- is finite
- is thin
- is skeletal
- has an initial object
- has binary products
- is locally cartesian closed
- is multi-algebraic
Deduced properties
- is locally finitely multi-presentable
- is a generalized variety
- is multi-cocomplete
- has effective congruences
- has pullbacks
- has binary powers
- is essentially small
- is locally small
- is countable
- is essentially finite
- has equalizers
- has a generating set
- is left cancellative
- is locally finite
- is one-way
- is connected
- has a multi-initial object
- is cofiltered
- has coequalizers
- has a cogenerating set
- is right cancellative
- has copowers
- has binary copowers
- has connected limits
- is finitely accessible
- has filtered-colimit-stable monomorphisms
- has sifted colimits
- is ℵ₁-accessible
- is Cauchy complete
- has coreflexive equalizers
- has effective cocongruences
- has reflexive coequalizers
- is inhabited
- has a strict initial object
- has wide pullbacks
- is locally essentially small
- is well-copowered
- is well-powered
- is essentially countable
- is direct
- is core-thin
- is cosifted
- has countable copowers
- is inverse
- is accessible
- has filtered colimits
- has quotients of congruences
- has sequential limits
- has cofiltered limits
- has a generator
- is gaunt
- is coaccessible
- has coquotients of cocongruences
- has sequential colimits
- has cofiltered-limit-stable epimorphisms
- has cosifted limits
- has finite copowers
- has a cogenerator
- is locally multi-presentable
- is locally poly-presentable
- has directed colimits
- has directed limits
Unsatisfied Properties
Assigned properties
- is not sifted
Deduced properties*
- is not filtered
- does not have binary coproducts
- is not self-dual
- is not trivial
- does not have a terminal object
- is not finitely cocomplete
- is not semi-strongly connected
- is not a groupoid
- does not have finite coproducts
- does not have pushouts
- does not have biproducts
- does not have a multi-terminal object
- is not strongly connected
- is not essentially discrete
- does not have disjoint finite coproducts
- is not distributive
- is not extensive
- is not balanced
- is not pointed
- does not have finite products
- does not have finite powers
- does not have zero morphisms
- is not an elementary topos
- is not co-Malcev
- is not counital
- is not additive
- is not cocartesian coclosed
- is not locally cocartesian coclosed
- is not cocomplete
- is not coregular
- does not have disjoint finite products
- is not infinitary codistributive
- is not countably codistributive
- is not codistributive
- does not have exact cofiltered limits
- does not have cocartesian cofiltered limits
- does not have a strict terminal object
- does not have countable coproducts
- does not have wide pushouts
- does not have a quotient object classifier
- does not have a regular quotient object classifier
- is not unital
- does not have a natural numbers object
- is not locally finitely presentable
- is not locally ℵ₁-presentable
- is not locally presentable
- is not locally strongly finitely presentable
- is not preadditive
- is not abelian
- is not cartesian closed
- is not finitely complete
- is not multi-complete
- is not discrete
- does not have disjoint coproducts
- is not infinitary distributive
- is not countably distributive
- does not have kernels
- does not have cartesian filtered colimits
- does not satisfy CIP
- is not infinitary extensive
- is not mono-regular
- is not normal
- does not have countable products
- does not have countable powers
- is not complete
- is not a Grothendieck topos
- is not locally copresentable
- does not have coproducts
- is not Barr-coexact
- does not have disjoint products
- does not have cokernels
- does not satisfy CSP
- is not coextensive
- is not epi-regular
- is not conormal
- does not have connected colimits
- is not Malcev
- is not Grothendieck abelian
- is not split abelian
- is not finitary algebraic
- does not have products
- is not regular
- does not have exact filtered colimits
- does not have powers
- does not have a subobject classifier
- does not have a regular subobject classifier
- is not subobject-trivial
- is not infinitary coextensive
- is not quotient-trivial
- is not Barr-exact
*This also uses the deduced satisfied properties.
Unknown properties
—
Special objects
- initial object:
- products: [binary case] , ,
Special morphisms
- isomorphisms: the three identities
- monomorphisms: every morphism
- epimorphisms: every morphism
- regular monomorphisms: same as isomorphisms
- regular epimorphisms: same as isomorphisms