ENTROPY OF PARTICLE PACKINGS - AN ILLUSTRATION ON A TOY MODEL

A toy model of particle packing is presented, which consists in arrang ing hexagons on a triangular lattice according to local stability rule s. The number of stable packings is analytically computed and found to grow exponentially with the size of the lattice, which illustrates th e concept of packing entropy first proposed by Edwards and collaborato rs. The analysis is carried out for both the monodispersed case and th e more interesting, i.e. more disordered, bidispersed case.