The general algorithm used here (of computing attraction and repulsion forces between pairs of particles) is very similar to that used in simulations of many in

The general algorithm used here (of computing attraction and repulsion forces between pairs of particles) is very similar to that used in simulations of many interesting phenomena in physics. Start with Smoothed Particle Hydrodynamics (https://en.wikipedia.org/wiki/Smoothed-particle_hydrodynamics https://en.wikipedia.org/wiki/Smoothed-particle_hydrodynamic...) and then check out Lagrangian Vortex Particle Methods and other N-Body problems (https://en.wikipedia.org/wiki/N-body_problem https://en.wikipedia.org/wiki/N-body_problem). And the algorithms to solve these quickly is another deep area of research.