Fr.: effondremenr d'onde
In the → Copenhagen Interpretation of → quantum mechanics, the change undergone by the → wave function of a particle when a measurement is performed on the particle. The wave function collapses to one that has a definite value for the quantity measured. If the → position of the matter wave is measured, it collapses to a localized → pulse. If → momentum is measured, it collapses to a wave with a definite momentum. Same as → collapse of the wave function.
Fr.: équation d'onde
The partial differential equation ∂2U / ∂2x + ∂2U / ∂2y + ∂2U / ∂2z = (1/c2) ∂2U / ∂2t or its counterparts in one or two dimensions or in other coordinates, the solution of which represents the propagation of displacementU as waves with velocity c.
Fr.: fonction d'onde
In → quantum mechanics, the function of space and time that satisfies → Schrodinger equation. The square of the modulus of its amplitude at any point represents the probability of finding a particle there.
→ wave; → function.
mekânik-e mowji (#)
Fr.: mécanique ondulatoire
One of the forms of quantum mechanics, due to Louis de Broglie and extended by E. Schrödinger. It originated in the suggestion that light consists of corpuscles as well as of waves and the consequent suggestion that all elementary particles are associated with waves.
Fr.: nature ondulatoire
adad-e mowj (#)
Fr.: nombre d'onde
Fr.: optique ondulatoire
The branch of optics that analyzes the electromagnetic radiation in terms of its wave characteristics. Also called → physical optics.
baste-ye mowj (#)
Fr.: paquet d'onde
→ wave; packet from M.E. pak "bundle" + diminutive suffix -et; maybe from M.Fr. pacquet.
Basté "packet," literally "bound, tied; set," p.p. of bastan "to form, bind, tie" (Mid.Pers. bastan/vastan "to bind, shut;" Av./O.Pers. band- "to bind, fetter," banda- "band, tie;" cf. Skt. bandh- "to bind, tie, fasten;" Ger. binden; E. bind; PIE base *bhendh- "to bind").
tiqe-ye mowj (#)
Fr.: lame à retard
An optical element that retards the phase of one plane of vibration of light relative to the plane at right angles. The two beams then recombine to form a single beam with new polarization characteristics. A typical wave plate is a birefringent crystal with a carefully chosen orientation and thickness. Also known as → retardation plate. A → half-wave plate creates a half-wave retardation. See also → quarter-wave plate.
wave theory of light
negare-ye mowji-ye nur
Fr.: théorie ondulatoire de la lumière
The theory that describes light as waves that spread out from the source that generates the light. It contradicts the → corpuscular theory of light proposed by Newton (1704). The idea of the wave nature of light was first put forward by Robert Hooke (1660). The wave theory was originally stated by Huygens (1690), who showed reflection and refraction could be explained by this theory. It was supported by → Young's experiment (1802) and established by the work of Fresnel (1814-1815). The wave theory received its most important support from Maxwell's → electromagnetic theory. See also → Huygens-Fresnel principle.
qatâr-e mowj (#), mowj-teran
Fr.: train d'onde
A series of successive waves spaced at regular intervals.
bordâr-e mowj (#)
Fr.: vecteur d'onde
A vector whose direction is that of propagation of a wave and whose magnitude is given by the → wave number, 2π/λ, where λ is the → wavelength, or ω/c, where ω is the → angular frequency and c is the speed of propagation.
Fr.: dualité onde-particule
The principle admitted in → quantum mechanics that
all particles have a wave-like nature and that waves have a particle aspect.
The wave-particle duality is of fundamental importance in obtaining a realistic picture of
the → elementary particles.
Fr.: bande de longueur d'onde
A portion of the electromagnetic spectrum which is defined because of its characteristics or for its use.
Fr.: forme d'onde
A graphical representation of the shape of a wave for a given instant in time.
Fr.: analyse de forme d'onde
The resolution of a complex waveform into a sum of simple periodic waves, usually by computer means.
pišân-e mowj, mowj-pišân
Fr.: front d'onde
The locus of adjacent points possessing the same phase in the path of a wave motion. Its surface is uniform (spherical or plane) and normal to propagation direction in an isotropic medium. → wavefront distortion.
aršâyeš-e pišân-e mowj
Fr.: correction de front d'onde
cowlegi-ye pišân-e mowj
Fr.: distortion de front d'onde
The disruption of the spherical shape of a wavefront due to atmospheric turbulence which makes the adjacent points in the wavefront out of phase.
hessgar-e pišân-e mowj
Fr.: analyseur de front d'onde
In adaptive optics, a device that analyzes the light sample coming from the wavefront and determines the error in each part of the beam. The wavefront sensor used in adaptive optics is a → Shack-Hartmann type, which works in conjunction with a deformable mirror.