category of sets with finite-to-one maps
- notation:
- objects: sets
- morphisms: maps with the property that for every the fiber is a finite set
- Related categories: ,
In this variant of we only consider maps with finite fibers, which are commonly called finite-to-one. Equivalently, every preimage of a finite set is again finite, and this description makes it obvious that composition is well-defined.
Satisfied Properties
Assigned properties
- is locally small
- has a generator
- has a cogenerator
- is semi-strongly connected
- is extensive
- has equalizers
- is epi-regular
- is well-copowered
- has quotients of congruences
- has effective congruences
- has effective cocongruences
- is locally cartesian closed
- is ℵ₁-accessible
- has ℵ₁-cofiltered limits
Deduced properties
- is accessible
- has ℵ₁-filtered colimits
- has pullbacks
- is mono-regular
- is connected
- has coreflexive equalizers
- is Cauchy complete
- has finite coproducts
- has disjoint finite coproducts
- has a strict initial object
- has a generating set
- is inhabited
- is locally essentially small
- is cofiltered
- has a cogenerating set
- is balanced
- is well-powered
- has an initial object
- has coquotients of cocongruences
- is cosifted
- has binary coproducts
- has finite copowers
- is sifted
- has a multi-initial object
- is ℵ₁-cofiltered
- has binary copowers
Unsatisfied Properties
Assigned properties
- is not skeletal
- is not locally finite
- is not strongly connected
- does not have binary powers
- does not have countable copowers
- is not filtered
- does not have sequential limits
- is not coaccessible
Deduced properties*
- does not have zero morphisms
- is not discrete
- is not finitely cocomplete
- does not have coequalizers
- is not ℵ₁-filtered
- does not have a terminal object
- does not have directed limits
- does not have countable products
- is not direct
- is not a groupoid
- does not have binary products
- does not have finite powers
- is not essentially finite
- is not thin
- is not gaunt
- is not locally copresentable
- is not essentially small
- does not have countable coproducts
- does not have ℵ₂-small copowers
- does not have sequential colimits
- is not inverse
- is not self-dual
- is not preadditive
- does not have biproducts
- is not right cancellative
- is not left cancellative
- does not have a multi-terminal object
- is not trivial
- is not essentially discrete
- does not have a strict terminal object
- is not countably distributive
- does not have kernels
- does not satisfy CIP
- is not pointed
- is not normal
- does not have ℵ₂-small products
- does not have finite products
- does not have countable powers
- is not small
- is not finite
- is not essentially countable
- is not subobject-trivial
- is not an elementary topos
- is not co-Malcev
- is not counital
- is not cocartesian coclosed
- is not cocomplete
- is not coregular
- does not have disjoint finite products
- is not countably codistributive
- does not have pushouts
- does not have reflexive coequalizers
- does not have cokernels
- does not have exact cofiltered limits
- does not satisfy CSP
- does not have cofiltered limits
- does not have directed colimits
- is not conormal
- does not have ℵ₂-small coproducts
- does not have copowers
- does not have connected colimits
- does not have a quotient object classifier
- does not have a regular quotient object classifier
- is not core-thin
- 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 additive
- is not abelian
- is not cartesian closed
- is not finitely complete
- is not multi-complete
- is not regular
- is not infinitary distributive
- is not distributive
- is not one-way
- does not have cartesian filtered colimits
- does not have filtered colimits
- does not have sifted colimits
- does not have products
- does not have ℵ₂-small powers
- does not have wide pullbacks
- is not countable
- is not a Grothendieck topos
- is not locally cocartesian coclosed
- does not have wide pushouts
- is not Barr-coexact
- does not have disjoint products
- is not codistributive
- is not infinitary codistributive
- is not quotient-trivial
- does not have cocartesian cofiltered limits
- does not have cofiltered-limit-stable epimorphisms
- is not coextensive
- does not have cosifted limits
- does not have coproducts
- is not Malcev
- is not Grothendieck abelian
- is not finitely accessible
- is not complete
- is not locally poly-presentable
- is not split abelian
- is not finitary algebraic
- is not a generalized variety
- is not Barr-exact
- does not have disjoint coproducts
- does not have exact filtered colimits
- does not have filtered-colimit-stable monomorphisms
- is not infinitary extensive
- does not have powers
- does not have connected limits
- does not have a subobject classifier
- does not have a regular subobject classifier
- is not infinitary coextensive
- is not locally multi-presentable
- is not locally finitely multi-presentable
- is not multi-algebraic
- is not a pretopos
- is not multi-cocomplete
*This also uses the deduced satisfied properties.
Unknown properties
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Special objects
- initial object: empty set
- coproducts: [finite case] disjoint union
Special morphisms
- isomorphisms: bijective maps
- monomorphisms: injective maps
- epimorphisms: surjective maps with finite fibers
- regular monomorphisms: same as monomorphisms
- regular epimorphisms: same as epimorphisms