Causality and Collisionless Damping in Plasma

Hee J. Lee, Mi Young Song

Department of Physics, Hanyang University, Seoul, Korea.
Plasma Technology Research Center, National Fusion Research Institute, Gunsan, Korea.

DOI: 10.4236/jmp.2013.44077                

Abstract

We derive the collisionless Landau damping in a plasma by satisfying the causal requirement that the susceptibility function of the plasma for time t < 0 should be nil. The causality condition should be satisfied by the susceptibility function of a plasma no matter what equations we employ to describe the plasma. Thus we conclude that the fundamental reason of the collisionless damping can be traced to the causality. As an example, we derive the collisionless damping of ion acoustic wave in a plasma by employing fluid equations.

Keywords

Causality; Landau Damping; Ion Acoustic Wave

Conflicts of Interest

The authors declare no conflicts of interest.

References

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