Resumen: General-purpose computation on Graphics Processing Units (GPU) on personal computers has recently become
an attractive alternative to parallel computing on clusters and supercomputers. We present the GPU-implementation of an
accurate molecular dynamics algorithm for a system of spheres. The new hybrid CPU-GPU implementation takes into
account all the degrees of freedom, including the quaternion representation of 3D rotations. For additional versatility, the
contact interaction between particles is defined using a force law of enhanced generality, which accounts for the elastic and
dissipative interactions, and the hard-sphere interaction parameters are translated to the soft-sphere parameter set. We prove
that the algorithm complies with the statistical mechanical laws by examining the homogeneous cooling of a granular gas with
rotation. The results are in excellent agreement with well established mean-field theories for low-density hard sphere systems.
This GPU technique dramatically reduces user waiting time, compared with a traditional CPU implementation.