Interlinking of two approaches for self-focusing of electromagnetic beam in a plasma?

Abstract

Several approaches for investigation of self-focusing of an electromagnetic beam propagating through a plasma have been developed. Each approach has its fundamentals, restrictions, conditions, limitations, etc. It is found that an expression derived for dielectric permittivity in one approach has been used in another approach and conclusions have drawn. Using such step as a reference, further similar activities may continue without caring for its validity. We have investigated the details of that interlinking, and have opined that the said interlinking may not be acceptable.