  We investigate the statistical mechanics of glass-forming materials and
jamming matter by means of a geometrically driven approach based on a revised
cell theory. By considering the system as constituted of jammed blocks of
increasing sizes, we obtain a unified picture that describes accurately the
whole process from low densities to limit densities at the glass/jamming
transition. The approach retrieves many of the aspects of existing theories
unifying them into a coherent framework. In particular, at low densities we
find a free volume regime, based on local relaxation process, at intermediate
densities a cooperative length sets in, where both local and cooperative
relaxation process are present. At even higher densities the increasing
cooperative length suppresses the local relaxation and only the cooperative
relaxation survives characterized by the divergence of the cooperative length,
as suggested by the random first order theory. Finally a relation between the
cooperative length and the hyperuniform length is also suggested.
