h-bar
E143960
h-bar is the reduced Planck constant, a fundamental physical constant that characterizes the scale of quantum effects in nature.
All labels observed (1)
| Label | Occurrences |
|---|---|
| h-bar canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T1250398 — 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: h-bar Context triple: [reduced Planck constant, alsoKnownAs, h-bar]
-
A.
HB
HB is the second-generation Holden Torana small family car series produced in the late 1960s, known for introducing more modern styling and engineering updates over its predecessor.
-
B.
BH
BH is the international vehicle registration code assigned to the Kingdom of Bahrain.
-
C.
HBC
HBC is the stock ticker symbol for Hudson's Bay Company, a historic Canadian retail business group known for its department stores and real estate holdings.
-
D.
HAV
HAV is the IATA airport code for José Martí International Airport, the main international gateway serving Havana, Cuba.
-
E.
HBE
HBE is the IATA airport code for Borg El Arab Airport, the main international airport serving Alexandria, Egypt.
- 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: h-bar Target entity description: h-bar is the reduced Planck constant, a fundamental physical constant that characterizes the scale of quantum effects in nature.
-
A.
HB
HB is the second-generation Holden Torana small family car series produced in the late 1960s, known for introducing more modern styling and engineering updates over its predecessor.
-
B.
BH
BH is the international vehicle registration code assigned to the Kingdom of Bahrain.
-
C.
HBC
HBC is the stock ticker symbol for Hudson's Bay Company, a historic Canadian retail business group known for its department stores and real estate holdings.
-
D.
HAV
HAV is the IATA airport code for José Martí International Airport, the main international gateway serving Havana, Cuba.
-
E.
HBE
HBE is the IATA airport code for Borg El Arab Airport, the main international airport serving Alexandria, Egypt.
- F. None of above. chosen
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
fundamental constant
ⓘ
physical constant ⓘ quantum constant ⓘ |
| alsoKnownAs |
Dirac constant
ⓘ
linked to:
reduced Planck constant
reduced Planck constant ⓘ |
| appearsIn |
Bohr model of the atom
ⓘ
Dirac equation ⓘ Heisenberg uncertainty principle ⓘ
linked to:
uncertainty principle
Klein–Gordon equation ⓘ Schrödinger equation ⓘ angular momentum quantization ⓘ canonical commutation relations ⓘ path integral formulation ⓘ spin operator eigenvalues ⓘ |
| belongsTo |
International System of Units (SI)
ⓘ
linked to:
International System of Units
|
| characterizes |
quantization of action
ⓘ
quantization of angular momentum ⓘ scale of quantum effects ⓘ |
| definedAs | h / (2π) ⓘ |
| governs | phase evolution of quantum states ⓘ |
| hasApproximateValue |
1.054571817e-34 J·s
ⓘ
6.582119569e-16 eV·s ⓘ |
| hasDimension | action ⓘ |
| hasDimensionSymbol | M L^2 T^-1 ⓘ |
| hasSIUnit | joule second ⓘ |
| introducedBy | Paul Dirac (notation) ⓘ |
| isDefinedVia | exact value of Planck constant h ⓘ |
| isExactSince | 2019-05-20 ⓘ |
| isProportionalityFactorIn |
E = ħω
ⓘ
J = Iħ for angular momentum eigenvalues ⓘ S = sħ for spin eigenvalues ⓘ p = ħk ⓘ |
| playsRoleIn |
quantum chromodynamics
ⓘ
quantum electrodynamics ⓘ quantum field theory ⓘ quantum mechanics ⓘ quantum optics ⓘ |
| relatedConcept |
Bohr radius
ⓘ
Planck constant h ⓘ
linked to:
Planck constant
fine-structure constant ⓘ quantum of action ⓘ |
| relatedTo | Planck constant ⓘ |
| symbolFor | reduced Planck constant ⓘ |
| usedIn |
Planck units
ⓘ
definition of atomic units ⓘ natural units ⓘ |
| usedToExpress |
energy-time uncertainty
ⓘ
position-momentum uncertainty ⓘ |
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: h-bar Description of subject: h-bar is the reduced Planck constant, a fundamental physical constant that characterizes the scale of quantum effects in nature.
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.