Helmholtz equation

E544889

The Helmholtz equation is a fundamental partial differential equation that describes time-harmonic wave propagation in fields such as acoustics, electromagnetism, and optics.

All labels observed (1)

Label Occurrences
Helmholtz equation canonical 2

Statements (49)

Predicate Object
instanceOf partial differential equation
appliesTo frequency-domain analysis
assumes linear medium
time-harmonic dependence e^{-iωt}
time-invariant medium
definedOn Euclidean space NERFINISHED
Riemannian manifolds NERFINISHED
describes time-harmonic wave propagation
domain linear wave phenomena
hasDependentVariable field amplitude
hasDimension can be formulated in 1D
can be formulated in 2D
can be formulated in 3D
hasIndependentVariable spatial coordinates
hasInhomogeneousForm ∇²u + k²u = -f
hasOperator Laplacian NERFINISHED
hasParameter wave number k
hasSolutionType cylindrical waves
plane waves
spherical waves
hasType homogeneous equation
models resonant modes in cavities
standing waves
wave scattering by obstacles
namedAfter Hermann von Helmholtz NERFINISHED
obtainedBy separation of variables in time from the wave equation
relatedTo Maxwell equations NERFINISHED
Schrödinger equation NERFINISHED
wave equation NERFINISHED
requires boundary conditions
radiation condition at infinity
solvedBy Fourier transform methods
Green function methods
boundary integral methods
finite difference methods
finite element methods
separation of variables
spectral methods
specialCaseOf Poisson equation NERFINISHED
symbolicForm ∇²u + k²u = 0
usedIn acoustic scattering
acoustics
antenna theory
electromagnetic scattering
electromagnetism
optics
quantum mechanics
seismology
vibration analysis

How these facts were elicited

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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
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- 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: Helmholtz equation
Description of subject: The Helmholtz equation is a fundamental partial differential equation that describes time-harmonic wave propagation in fields such as acoustics, electromagnetism, and optics.

Referenced by (2)

Full triples — surface form annotated when it differs from this entity's canonical label.

Kirchhoff diffraction theory relatesTo Helmholtz equation
Sommerfeld radiation condition appliesTo Helmholtz equation