Critique of Electromagnetic Turbulent-Plasma Scattering Theories

Abstract

The scattering of electromagnetic waves by a large-scale turbulent plasma has recently become of interest again in connection with the formation and study of the nonequilibrium plasma (often turbulent) of controlled fusion machines. Other than the usual Born approximation, it has also become fashionable to use the equivalent of the Dyson and Bethe-Salpeter equations, as well as a transport formulation for the scattering wave. The use of these methods has recently been justified by Frisch. These results are considered in a critical fashion. It has been possible to conclude that the results obtained from a solution of the stochastic transport theory are valid in both the high- and low-frequency limits, while the results of the smoothing approximation for the Dyson and Bethe-Salpeter equations are limited to the low-frequency limit. In addition, it has also been concluded that the secular effects that exist in the ordinary Born series may be fictional.