Current Trends in Research on Nonlinear Effects in Plasma

Abstract

In this final chapter we take a look at some of the most important trends in the development of nonlinear plasma theory. Current research may be grouped into: 1) investigations in which the theory of nonlinear interactions is elaborated on a broad scale, i.e., toward a more detailed analysis of nonlinear interactions within the theoretical context of weak nonlinearity; 2) investigations invoking new approaches. In the first category we include theories based on the kinetic equations for plasmons (Sec. 1 of the present chapter) and theories of the nonlinear plasma dispersive properties (Sec. 2). The new approaches attempt to transcend the weak nonlinearity concept, i.e., by and large to circumvent expansions in the amplitudes of the interacting fields. This category includes the investigation of nonlinear plasma instabilities (Sec. 3), the investigation of the dispersion characteristics of plasma in strong external fields (Sec. 4), the investigation of large-amplitude nonlinear waves (Sec. 5), etc.