A set of hard spheres with tangential inelastic collision is found to reproduce observations of real and numerical granular matter. After time is scaled so as to cancel energy dissipation due to inelastic collisions out, inelastically colliding hard spheres in two dimensional space come to have 1=f uctua-tion of total energy, non-Gaussian distribution of displacement vectors, and convective mot...

Phase diagrams of hard and soft spheres with a fixed dipole moment are determined by calculating the Helmholtz free energy using simulations. The pair potential is given by a dipole-dipole interaction plus a hard-core and a repulsive Yukawa potential for soft spheres. Our system models colloids in an external electric or magnetic field, with hard spheres corresponding to uncharged and soft sphe...

A mean-field nonlinear equation for the mean-square displacement, recently proposed by one of the present authors [M. Tokuyama, Phys. Rev. E 62, R5915 (2000); Physica A 289, 57 (2001)], for concentrated, equilibrium suspensions of hard spheres is extended to describe equilibrium atomic systems of hard spheres. The validity of two types of mean-field equations is investigated by two kinds of com...

Frank Rietz, 2, 3, 4, ∗ Charles Radin, Harry L. Swinney, and Matthias Schröter 2, † Max-Planck-Institute for Dynamics and Self-Organization Göttingen, 37077 Göttingen, Germany Institute for Multiscale Simulation, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91052 Erlangen, Germany Department of Nonlinear Phenomena, University Magdeburg, Universitätsplatz 2, 39106 Magdeburg, Germany ...

We numerically calculate the configurational entropy Sconf of a binary mixture of hard spheres, by using a perturbed Hamiltonian method trapping the system inside a given state, which requires less assumptions than the previous methods [R.J. Speedy, Mol. Phys. 95, 169 (1998)]. We find that Sconf is a decreasing function of packing fraction φ and extrapolates to zero at the Kauzmann packing frac...

Freezing of polydisperse hard spheres is studied by Monte Carlo simulation and the results are interpreted with a cell model of the solid. The results supplement an earlier study of freezing of nearly monodisperse hard spheres and, within the assumption of a substitutionally disordered solid, a complete description of the freezing behavior is obtained. The density and polydispersity of the prec...