Exploratory study of the glassy landscape near jamming

We present a study of the landscape structure of hard and soft spheres as a function of the packing fraction and of the energy. We find that, on approaching the jamming transition, the number of different configurations available to the system increases steeply and a hierarchical organization of the landscape emerges. We use the knowledge of the structure of the landscape to predict the values of thermodynamic observables on the edge of the transition.