Reissner–Nordström metric
E14555
Lorentzian metric
black hole metric
electrovacuum solution
exact solution of Einstein field equations
spherically symmetric spacetime
static spacetime
The Reissner–Nordström metric is an exact solution in general relativity describing the spacetime geometry outside a static, spherically symmetric, electrically charged black hole.
All labels observed (5)
| Label | Occurrences |
|---|---|
| Reissner–Nordström black hole | 5 |
| Reissner–Nordström metric canonical | 4 |
| Reissner–Nordström spacetime | 3 |
| Reissner–Nordström solution | 2 |
| Reissner–Nordström radius for charged black holes | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T79914 — 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: Reissner–Nordström metric Context triple: [Einstein field equations, admitsSolution, Reissner–Nordström metric]
-
A.
Kerr metric
The Kerr metric is the exact general relativity solution describing the spacetime geometry around a rotating, uncharged black hole.
-
B.
Schwarzschild black hole
A Schwarzschild black hole is the simplest theoretical black hole solution in general relativity, describing a static, spherically symmetric, non-rotating, uncharged mass with an event horizon defined by the Schwarzschild radius.
-
C.
Eddington–Finkelstein coordinates
Eddington–Finkelstein coordinates are a coordinate system in general relativity that smoothly covers a black hole’s event horizon, avoiding the coordinate singularity present in standard Schwarzschild coordinates.
-
D.
Kruskal–Szekeres coordinates
Kruskal–Szekeres coordinates are a maximal extension coordinate system used in general relativity to smoothly describe the entire spacetime of a Schwarzschild black hole, including regions across the event horizon.
-
E.
Schwarzschild radius
The Schwarzschild radius is the critical distance from the center of a non-rotating, spherically symmetric mass at which its escape velocity equals the speed of light, defining the boundary of a black hole.
- 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: Reissner–Nordström metric Target entity description: The Reissner–Nordström metric is an exact solution in general relativity describing the spacetime geometry outside a static, spherically symmetric, electrically charged black hole.
-
A.
Kerr metric
The Kerr metric is the exact general relativity solution describing the spacetime geometry around a rotating, uncharged black hole.
-
B.
Schwarzschild black hole
A Schwarzschild black hole is the simplest theoretical black hole solution in general relativity, describing a static, spherically symmetric, non-rotating, uncharged mass with an event horizon defined by the Schwarzschild radius.
-
C.
Eddington–Finkelstein coordinates
Eddington–Finkelstein coordinates are a coordinate system in general relativity that smoothly covers a black hole’s event horizon, avoiding the coordinate singularity present in standard Schwarzschild coordinates.
-
D.
Kruskal–Szekeres coordinates
Kruskal–Szekeres coordinates are a maximal extension coordinate system used in general relativity to smoothly describe the entire spacetime of a Schwarzschild black hole, including regions across the event horizon.
-
E.
Schwarzschild radius
The Schwarzschild radius is the critical distance from the center of a non-rotating, spherically symmetric mass at which its escape velocity equals the speed of light, defining the boundary of a black hole.
- F. None of above. chosen
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
Lorentzian metric
ⓘ
black hole metric ⓘ electrovacuum solution ⓘ exact solution of Einstein field equations ⓘ spherically symmetric spacetime ⓘ static spacetime ⓘ |
| associatedElectromagneticPotential | A_\mu dx^\mu = -\frac{Q}{r} dt ⓘ |
| BekensteinHawkingEntropy | S = \frac{A_+}{4} with A_+ = 4\pi r_+^2 ⓘ |
| belongsToTheory | general relativity ⓘ |
| canBeExtendedBy |
Eddington–Finkelstein coordinates
ⓘ
Kruskal-like coordinates ⓘ |
| dependsOnParameter |
electric charge parameter Q
ⓘ
mass parameter M ⓘ |
| describes |
electrically charged black hole
ⓘ
spacetime geometry outside a static spherically symmetric electrically charged mass ⓘ |
| energyMomentumSource | electromagnetic field of a point charge ⓘ |
| generalizes | Schwarzschild solution to include electric charge ⓘ |
| hasCauchyHorizon | at r = r_- for |Q| < M ⓘ |
| hasCausalStructure | with multiple asymptotic regions in maximal analytic extension ⓘ |
| hasCoordinateSingularity | at r = r_+ in Schwarzschild-like coordinates ⓘ |
| hasCoordinateSystem |
Schwarzschild coordinates
ⓘ
surface form:
Schwarzschild-like coordinates
|
| hasCurvatureSingularity | at r = 0 ⓘ |
| hasEventHorizon | at r = r_+ for |Q| \le M ⓘ |
| hasInnerHorizonRadius | r_- = M - \sqrt{M^2 - Q^2} ⓘ |
| hasIsometryGroup | R × SO(3) ⓘ |
| hasKillingVectorField |
\partial_t
ⓘ
generators of SO(3) rotations ⓘ |
| hasNakedSingularityWhen | |Q| > M ⓘ |
| hasOuterHorizonRadius | r_+ = M + \sqrt{M^2 - Q^2} ⓘ |
| hasSymmetry |
spherical symmetry
ⓘ
time-translation symmetry ⓘ |
| HawkingTemperature | T_H = \frac{\kappa_+}{2\pi} ⓘ |
| HawkingTemperatureExtremal | T_H = 0 for |Q| = M ⓘ |
| isAsymptotically | flat ⓘ |
| isExtremalWhen | |Q| = M ⓘ |
| isSolutionType | static spherically symmetric electrovacuum solution ⓘ |
| isUsedIn |
analyses of cosmic censorship conjecture
ⓘ
studies of charged black hole thermodynamics ⓘ studies of inner horizon instability ⓘ |
| lineElement | ds^2 = -\left(1 - \frac{2M}{r} + \frac{Q^2}{r^2}\right) dt^2 + \left(1 - \frac{2M}{r} + \frac{Q^2}{r^2}\right)^{-1} dr^2 + r^2 d\Omega^2 ⓘ |
| namedAfter |
Gunnar Nordström
ⓘ
Hans Reissner ⓘ |
| obeys | Birkhoff-like theorem for charged spherically symmetric solutions ⓘ |
| reducesTo | Schwarzschild metric when Q = 0 ⓘ |
| satisfies | vacuum Einstein equations with electromagnetic stress-energy tensor ⓘ |
| solves | Einstein–Maxwell equations ⓘ |
| surfaceGravityAtOuterHorizon | \kappa_+ = \frac{\sqrt{M^2 - Q^2}}{r_+^2} ⓘ |
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: Reissner–Nordström metric Description of subject: The Reissner–Nordström metric is an exact solution in general relativity describing the spacetime geometry outside a static, spherically symmetric, electrically charged black hole.
Referenced by (15)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
Reissner–Nordström radius for charged black holes
this entity surface form:
Reissner–Nordström black hole
this entity surface form:
Reissner–Nordström black hole
this entity surface form:
Reissner–Nordström black hole
this entity surface form:
Reissner–Nordström spacetime
this entity surface form:
Reissner–Nordström solution
this entity surface form:
Reissner–Nordström solution
this entity surface form:
Reissner–Nordström black hole
subject surface form:
Penrose–Carter diagram
this entity surface form:
Reissner–Nordström spacetime
this entity surface form:
Reissner–Nordström black hole
this entity surface form:
Reissner–Nordström spacetime