Nuclear matter at subsaturation densities is expected to be inhomogeneous, owing to the existence
of many-body correlations, which constitutes an essential feature for the construction of a reliable
equation of state. A first emergent phenomenon related to this aspect is the fragmentation
process, experimentally observed in heavy-ion collisions at intermediate energies as the result
of mechanical (spinodal) instabilities driven by the mean-field, in connection to the occurrence
of a liquid-gas phase transition. On the other hand, at even smaller densities, owing to residual
few-body correlations, also the formation of light clusters as deuterons, or particularly strongly
bound 𝛼 particles which dissolve with increasing density due to the Pauli principle, is considered
well established.
A consistent description of light clusters at low densities and the formation of heavy fragments
through spinodal instabilities within the same theoretical approach is however still missing nowa-
days. In this work, we propose then a novel approach to include light clusters degrees of freedom
within a non-relativistic kinetic theory based on energy density functionals, providing a unified
dynamical framework to account at once for both phenomena, when out of equilibrium processes,
as they occur in nuclear reactions, are considered. Implications for general aspects of reactions
dynamics and in the widest scope of astrophysical applications are envisaged and discussed.