Fundamental problems in statistical physics of jammed packings

For packed i.e., “jammed”, hard and rough objects kinetic energy is a minor and ignorable quantity, as is elastic strain. Hence in the static case, the stress equations need supplementing by “missing equations” depending solely on configurations. A different pathway of analysis is the calculation of the probability distribution of interparticle forces. This paper presents the mini-review of recently obtained results in this field and poses a number of fundamental problems which are yet to be solved.