A theory of incoherent scattering of radio waves by a plasma, 5. The use of the Nyquist Theorem in general quasi-equilibrium situations

摘要: The Nyquist or fluctuation-dissipation theorem applies strictly only to linear systems in thermal equilibrium. However, it can also be used successfully calculate fluctuating quantities quasi-equilibrium, a familiar example being circuit with elements at different temperatures. An analogous calculation carried out for plasma, considering each particle species as separate element of the system. One calculates spontaneous force generated by (with its own temperature and mean drift velocity) set transfer functions which relate these forces electron perturbations are responsible scattering. important point realize plasma case is that, this approach, electric field perturbations, couple together, enter through function not involved statistics ‘generalized forces.’ results obtained apply multiple ion unequal temperatures, velocities, charges (including negative), etc., agree similar calculations based on dressed approach.