Properties of plasmas
Properties of plasmas
复制标题
等离子体的性质
作者：
A. Sitenko
CONTEMPORARY plasma theory is based largely on statistical methods-but there are different techniques for describing the properties of the statistical system. AG Sitenko proposed a detailed description of statistical and electrodynamical plasma properties, based on the consideration of fluctuations. Of fundamental importance in this description are the spectral correlation functions, which have simple analytical properties. In linear electrodynamics the fluctuation-dissipation theorem establishes a relation between fluctuations of different quantities and electrodynamic properties of the medium. That is why, once we know the fluctuation spectrum in plasmas, we can determine the electric plasma susceptibility by inversion of the fluctuation-dissipation theorem. The generalisation of this theorem for the non-linear case allows the description of non-linear electrodynamic plasma properties. Allowing for the non-linear wave interaction explains the saturation of the fluctuation level in non-equilibrium plasma under critical conditions. This level, corresponding to the stationary turbulent plasma state, can exceed the thermal level significantly. The~: inetic equation for waves is derived, taking into account the interaction of waves with fluctuating fields in plasmas. To neglect this interaction (a procedure adopted in many papers) is not valid in nonequilibrium plasmas. In the stationary case the solution of the kinetic equation determines the fluctuation spectrum for the turbulent plasma state. Such an approach is very prOmISIng when consid (; ring the scattering and transformation of waves in plasmas
