Plasma Physics-An Elementary Review

Although plasma phenomena have been observed in nature since the beginning of time, it is only in recent years that man has recognized the vast potential that plasmas hold for his future activities. One needs only to consider the scale of present day plasma physics experiments in order to realize the emphasis now being placed on the subject. At one extreme, there is the formation of artificial plasmas in nature such as in the Argus experiment and at the other is the study of microplasmas in tiny crystals of semiconducting material. This paper summarizes the role plasma physics is playing in present day scientific activities. A brief description is given of plasmas in nature, of the role of plasma physics in attempts at the ignition, control and diagnosis of thermonuclear fusion reactions, of the effect of plasmas on communication and telemetry from space and re-entry vehicles, of propulsion techniques (ionic, magneto-hydrodynamic, plasma) which utilize plasmas, and of the possibilities of incorporating plasmas in practical devices. In conclusion, the future prospects of plasma physics are outlined.