Re:Scientists Watch as Heat Moves at the Speed of Sound
by freethemullet on Sunday March 24, 2019 @02:17PM
(#19477815)
Long wavelength phonons are the familiar sound waves. Smaller wavelength phonons have different group velocities due to dispersion.
The speed of second sound is not the same speed of first sound. The speed of second sound is essentially determined by a weighted contribution of the different of speeds of the different phonon modes that collectively participate to produce a temperature wave.
The speed of second sound is not the same speed of first sound. The speed of second sound is essentially determined by a weighted contribution of the different of speeds of the different phonon modes that collectively participate to produce a temperature wave.