  The time evolution and stationary values of the entropy per particle of a
homogeneous freely cooling granular gas, relative to the maximum entropy
consistent with the instantaneous translational and rotational temperatures, is
analyzed by means of a Sonine approximation involving fourth-degree cumulants.
The results show a rich variety of dependencies of the relative entropy on time
and on the coefficients of normal and tangential restitution, including a
peculiar behavior in the quasi-smooth limit.
