# Anomalous dispersion

- Author:
- alfredolouro

This animation shows the superposition of two waves with close frequencies. The result is a wave with the average frequency and wave number, modulated by a wave with much lower frequency (equal to their difference), and wave number (also equal to their difference).
In this case, the dispersion relation is such that the group velocity is bigger than the phase velocity. Animate the time slider to see the effect.