Physics of collisionless plasma

Review of papers dealing with two alternative methods of describing nonequilibrium processes in fully ionized plasma. The example of 'Landau damping' is used to demonstrate that a number of fundamental problems remain unsolved in the kinetic theory of plasma. They arise from inconsistent description of transition from the reversible equations of mechanics of charged particles and field to the irreversible equations of continuous medium in statistical theory of plasma. These difficulties can be overcome through consistently defining the structure of continuous medium and the characteristics of dynamic instability of motion. This leads to generalized irreversible equations which provide the basis for unified description of nonequilibrium processes in plasma on kinetic and hydrodynamic scales.