A soft collision detection algorithm for simple Brownian dynamics

We describe a collision detection algorithm for spherical bodies that performs a minimal amount of computation consistent with maintaining reasonable steric exclusion. The algorithm was tested using populations of bodies that move randomly without inertia, simulating Brownian-like motion. Simulations were tested using populations of different size, up to 100,000 bodies, at different densities. The algorithm is linear in time and memory with the number of bodies and would be suitable for the simulation of ‘soft’ objects, such as cells.