A Statistical Mechanics Approach to the Inherent States of Granular Media

We consider a Statistical Mechanics approach to granular systems by following the original ideas developed by Edwards. We use the concept of ``inherent states'', defined as the stable configurations in the potential energy landscape, introduced in the context of glasses. Under simplifying assumptions, the equilibrium inherent states can be characterised by a configurational temperature, $1/\beta$. We link $\beta$ to Edwards' compactivity and address the problem of its experimental measure. We also discuss the possibility to describe the time dependent distribution probability in the inherent states with an appropriate master equation.