Massless Particles

Colloidal particles are small and the inertial effect of the particle is also neglected in the conventional Stokesian dynamics. The dynamics for such massless particles are

$$\frac{{\rm d}\bm{x}}{{\rm d}t} = \bm{U} ,$$ (2.14)

where $\bm{U}$ is the particle velocity. For massless particles, $\bm{U}$ is obtained by the mobility (or mixed) problem

$$\bm{U} = \bm{M}\cdot\bm{F}_{\text{ext}} ,$$ (2.15)

where $\bm{F}_{\text{ext}}$ is the external force acting on the particle.

To simulate the massless particle, set the parameter ``stokes'' in the initialization script zero.