Inherent nonlinearity of fluid motion and acoustic gravitational wave memory

We consider the propagation of nonlinear sound waves in a perfect fluid at rest. By employing Riemann wave equation acoustics one spatial dimension, it is shown that carrying constant density perturbation their tails produce an acoustic analogue gravitational memory. For memory, which general nonlinear, nonlinearity effective spacetime dynamics not due to Einstein equations, but equations. concreteness, we employ box-trapped Bose-Einstein condensate, and suggest experimental protocol observe