von Neumann universe
E14977
The von Neumann universe is a cumulative, well-founded hierarchy of sets used as a standard model of the set-theoretic universe in axiomatic set theory.
All labels observed (3)
| Label | Occurrences |
|---|---|
| von Neumann universe canonical | 13 |
| cumulative hierarchy of sets | 1 |
| von Neumann cumulative hierarchy | 1 |
Statements (49)
| Predicate | Object |
|---|---|
| instanceOf |
class
ⓘ
cumulative hierarchy ⓘ proper class ⓘ set-theoretic universe ⓘ |
| alsoKnownAs |
von Neumann universe
ⓘ
surface form:
cumulative hierarchy of sets
|
| builtByTransfiniteRecursionOn | ordinals ⓘ |
| choiceAxiomMayHoldIn | von Neumann universe self-link ⓘ |
| contains | all sets (in ZF/ZFC) as elements of some level V_α ⓘ |
| containsAsSubstructure | cumulative hierarchy of hereditarily finite sets ⓘ |
| cumulativeProperty | for all α, V_α = ⋃_{β<α} V_β for limit α and P(V_{α−1}) for successors ⓘ |
| definedIn | axiomatic set theory ⓘ |
| extensionalityAxiomHoldsIn | von Neumann universe self-link ⓘ |
| firstInfiniteLevel | V_ω ⓘ |
| foundationAxiomHoldsIn | von Neumann universe self-link ⓘ |
| hasProperty |
cumulative
ⓘ
rank-initial segment structure ⓘ transitive ⓘ well-founded ⓘ |
| historicallyIntroducedBy | John von Neumann in the 1920s ⓘ |
| infinityAxiomHoldsIn | von Neumann universe self-link ⓘ |
| isTransitiveClass | von Neumann universe self-link ⓘ |
| isUnionOf | V_α for all ordinals α ⓘ |
| levelNotation |
V_0 = ∅
ⓘ
V_{α+1} = P(V_α) ⓘ V_λ = ⋃_{β<λ} V_β for limit ordinal λ ⓘ |
| membershipRelationRestrictedTo | V forms a well-founded relation ⓘ |
| namedAfter | John von Neumann ⓘ |
| pairingAxiomHoldsIn | von Neumann universe self-link ⓘ |
| powerSetAxiomHoldsIn | von Neumann universe self-link ⓘ |
| rankFunctionCharacterization | x ∈ V_α iff rank(x) < α ⓘ |
| rankFunctionCodomain | ordinals ⓘ |
| rankFunctionDomain | all sets ⓘ |
| relatedConcept |
Grothendieck universe
ⓘ
constructible universe L ⓘ rank hierarchy ⓘ |
| replacementAxiomHoldsIn | von Neumann universe self-link ⓘ |
| satisfies |
Zermelo–Fraenkel set theory
ⓘ
surface form:
Zermelo–Fraenkel set theory (ZF) under suitable assumptions
Zermelo–Fraenkel set theory ⓘ
surface form:
Zermelo–Fraenkel set theory with Choice (ZFC) under suitable assumptions
|
| separationSchemaHoldsIn | von Neumann universe self-link ⓘ |
| subsetRelation | for each α, V_α ⊂ V ⓘ |
| symbol | V ⓘ |
| unionAxiomHoldsIn | von Neumann universe self-link ⓘ |
| usedAs | standard model of the set-theoretic universe ⓘ |
| usedIn |
forcing arguments (as ambient universe)
ⓘ
inner model theory ⓘ relative consistency proofs ⓘ |
| V_0Equals | empty set ⓘ |
| V_1Contains | all subsets of the empty set ⓘ |
| V_ωContains | all hereditarily finite sets ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: von Neumann universe Description of subject: The von Neumann universe is a cumulative, well-founded hierarchy of sets used as a standard model of the set-theoretic universe in axiomatic set theory.
Referenced by (15)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
von Neumann cumulative hierarchy
this entity surface form:
cumulative hierarchy of sets