The Physics of transport processes
By Paolo Di Sia
The physics of transport processes has been and is currently a very important sector in the description and
understanding of the “infinitely small and big”. Nanophysics is demonstrating in recent years the richness of
phenomena occurring at the nano-scale. A new formulation of the Drude-Lorentz model offers analytical expressions of the most important transport parameters, i.e. the velocities correlation function, the mean square deviation of position and the diffusion coefficient of a system. The model contains a gauge factor, which allows its use from sub-pico-level to macro-level. With this model it is possible to deeply investigate this range and to study interesting applications, from everyday life to cosmology. Moreover very interesting is also the deep study of the involved mathematics, i.e. contour integration in the complex plane, for finding the poles of studied expressions of conductivity. The procedure is mathematically very elegant, because it is analytical calculation.