That is, the path follows the fluid current described by the fluid's velocity field 'v'.
For the more general cases, independent of whether a velocity field can be used or not, the continuity equation becomes:
Say the aether has velocity field as a function of .
The governing equations are thus transformed, and the solution is a filtered velocity field.
The role of the wavefunction is to generate the velocity field for the particles.
Even with one space dimension and a constant velocity field, the system remains difficult to simulate.
The idea is that a velocity field can also be understood as a first order differential operator acting on functions.
The velocity field may be represented by a function that must satisfy:
Other choices of density and pressure are possible with the same velocity field:
Once the velocity field is solved for, other quantities of interest (such as flow rate or drag force) may be found.