Ehrenfest paradox
E735841
The Ehrenfest paradox is a thought experiment in special relativity that highlights the apparent contradictions arising from applying relativistic length contraction to a rigid rotating disk.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Ehrenfest paradox canonical | 2 |
How this entity was disambiguated
This entity first appeared as the object of triple T8490719 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Ehrenfest paradox Context triple: [Paul Ehrenfest, notableWork, Ehrenfest paradox]
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A.
Tolman–Ehrenfest effect
The Tolman–Ehrenfest effect is a relativistic thermodynamic phenomenon stating that, in a system at thermal equilibrium within a gravitational field, temperature varies with gravitational potential so that hotter regions occur deeper in the gravitational well.
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B.
Lorentz contraction
Lorentz contraction is the special relativistic effect in which an object’s length along the direction of motion appears shortened to observers in a different inertial frame moving at high relative velocity.
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C.
de Sitter effect
The de Sitter effect is a relativistic phenomenon in celestial mechanics describing how general relativity alters the motion and precession of orbiting bodies in a gravitational field.
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D.
Einstein's elevator
Einstein's elevator is a famous thought experiment devised by Albert Einstein to illustrate the equivalence between gravitational and inertial effects, forming a key conceptual basis for general relativity.
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E.
Das Relativitätsprinzip
"Das Relativitätsprinzip" is a foundational work on the theory of relativity that helped systematize and popularize Albert Einstein’s ideas in the early 20th century.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Ehrenfest paradox Target entity description: The Ehrenfest paradox is a thought experiment in special relativity that highlights the apparent contradictions arising from applying relativistic length contraction to a rigid rotating disk.
-
A.
Tolman–Ehrenfest effect
The Tolman–Ehrenfest effect is a relativistic thermodynamic phenomenon stating that, in a system at thermal equilibrium within a gravitational field, temperature varies with gravitational potential so that hotter regions occur deeper in the gravitational well.
-
B.
Lorentz contraction
Lorentz contraction is the special relativistic effect in which an object’s length along the direction of motion appears shortened to observers in a different inertial frame moving at high relative velocity.
-
C.
de Sitter effect
The de Sitter effect is a relativistic phenomenon in celestial mechanics describing how general relativity alters the motion and precession of orbiting bodies in a gravitational field.
-
D.
Einstein's elevator
Einstein's elevator is a famous thought experiment devised by Albert Einstein to illustrate the equivalence between gravitational and inertial effects, forming a key conceptual basis for general relativity.
-
E.
Das Relativitätsprinzip
"Das Relativitätsprinzip" is a foundational work on the theory of relativity that helped systematize and popularize Albert Einstein’s ideas in the early 20th century.
- F. None of above. chosen
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
paradox in physics
ⓘ
special relativity paradox ⓘ thought experiment ⓘ |
| addresses |
consistency of special relativity with rotating rigid disks
ⓘ
definition of rigidity in relativistic physics ⓘ geometry of space measured by rotating observers ⓘ |
| context |
discussion of rigid bodies in relativity
ⓘ
early development of special relativity ⓘ |
| describes |
apparent contradiction between special relativity and rigid rotation
ⓘ
different length contraction of circumference and radius of a rotating disk ⓘ incompatibility of global rigid rotation with special relativity ⓘ non-Euclidean spatial geometry in rotating frames ⓘ relativistic effects in rotating frames ⓘ |
| field |
special relativity
ⓘ
theoretical physics ⓘ |
| hasAspect |
application of Lorentz contraction to a rotating rim
ⓘ
assumption of a perfectly rigid disk ⓘ stress and strain in relativistic rotating bodies ⓘ transition from rest to uniform rotation ⓘ |
| hasConsequence |
demonstrates impossibility of perfectly rigid bodies in relativity
ⓘ
implies spatial geometry in rotating frame is non-Euclidean ⓘ motivates use of general relativity for rotating systems ⓘ shows limitations of naive application of Lorentz contraction ⓘ |
| mainSubject |
Born rigidity
ⓘ
circumference-to-radius ratio ⓘ length contraction ⓘ non-inertial reference frames ⓘ relativistic rigidity ⓘ relativistic rotation ⓘ rigid body motion ⓘ rotating disk ⓘ spacetime geometry ⓘ |
| namedAfter | Paul Ehrenfest ⓘ |
| proposedBy | Paul Ehrenfest ⓘ |
| publicationYear | 1909 ⓘ |
| relatedTo |
Bell's spaceship paradox
ⓘ
Born rigidity ⓘ Lorentz contraction ⓘ Minkowski spacetime ⓘ
linked to:
Minkowski space-time
Sagnac effect ⓘ
linked to:
Sagnac interferometer
general relativity ⓘ non-inertial coordinate systems ⓘ relativistic rigid body problem ⓘ rotating reference frames ⓘ |
| resolvedBy |
abandonment of perfectly rigid bodies in relativity
ⓘ
introduction of Born rigidity concept ⓘ recognition of non-Euclidean spatial geometry in rotating frames ⓘ |
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: Ehrenfest paradox Description of subject: The Ehrenfest paradox is a thought experiment in special relativity that highlights the apparent contradictions arising from applying relativistic length contraction to a rigid rotating disk.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.
subject linked to:
Ehrenfest