Figure 1. Schematic representation of inelastic collisions between wave-packets and liquid particles. The event represented in (a), in which an energetic wave-packet transfers energy and momentum to a liquid particle, is commuted upon time reversal into the one represented in (b), where a liquid particle transfers energy and momentum to a wavepacket. The particle changes velocity and the frequency of wave-packet is shifted by the amount 12 . Due to its time symmetry, we assume this mechanism is the equivalent of Onsager’ reciprocity law at microscopic level [31-33].
...read more