Group velocity / Phase velocity Animation

Here, we demonstrate the group and phase velocity phenomena as observed when two signals with different temporal and spectral frequencies (wavelength) are added to each other. The addition creates time varying constructive and destructive interferences along the space. The resulting wave packet travels with the so-called group velocity which is faster than the phase velocity in this case. The wave packet envelope is shown in magenta color in dashed lines. Note that in this particular case, both group and phase velocities are positive. An important interpretation of group velocity is that it represents the velocity at which the energy or information is conveyed along a wave (see Wikipedia for further details). 

Групповая скорость, Gruppengeschwindigkeit, Voortplantingssnelheid, Velocidad de grupo, Grupa rapido, Vitesse de groupe, Velocità di gruppo, 군속도, מהירות חבורה, ჯგუფური სიჩქარე, 群速度, Gruppefart, Prędkość grupowa, Групова швидкість, 群速度, Vận tốc nhóm, Grupphastighet, Grupinis greitis Phasengeschwindigkeit, Velocidad de fase, 相速度, Vitesse d'une onde, Velocità di fase, Фазовая скорость, 位相速度