“…The original DK equation includes nonlinear terms of dynamic origin due to the kinetic coefficient that is proportional to fluctuating field [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 ]. While the nonlinearility of the original DK equation leads to the above successful descriptions of various phenomena [ 16 , 17 , 18 , 19 , 20 ], a more tractable form is required. It has been recently demonstrated that the DK equation can be linearized with respect to when , and that the linear stochastic equation of density fluctuations is of great practical use [ 21 , 22 , 23 , 24 , 25 , 26 , 27 ].…”