Nondispersive wave
= Nondispersive wave
= Nondispersive
{synonym}
A nondispersive wave has constant <phase velocity> on a propagation branch. For $\omega=ck$, its <group velocity> is also $c$. A <frequency> relation with a nonzero offset, such as $\omega=ck+b$, has constant <group velocity> but a <phase velocity> $c+b/k$ depending on <wavenumber>; constant <group velocity> alone is therefore not sufficient for nondispersion.