Nonlinear Boltzmann equation for the homogeneous isotropic case: minimal deterministic Matlab program The problem consists in integrating the homogeneous Boltzmann equation for a generic collisional kernel in case of isotropic symmetry, by a deterministic direct method. Difficulties arise from the multi-dimensionality of the collisional operator and from satisfying the conservation of particle number and energy (momentum is trivial for this test case) as accurately as possible, in order to preserve the late dynamics. (Source: http://cpc.cs.qub.ac.uk/summaries/)