Resonances and dispersion in relativistic plasmas

Relativistic plasmas are reviewed emphasizing the relation between resonance, dissipation and dispersion. The resonance condition is derived by imposing conservation of 4-momentum at a microscopic level. The response of a plasma is described in a manifestly covariant manner, and explicit forms including relativistic quantum effects are written down. Properties of some specific relativistic plasma dispersion functions are described briefly. The Einstein coefficients are used to derive kinetic equations that describe the effect of resonant interactions on the distributions of waves and particles.