CALIFORNIA UNIV LOS ANGELES SCHOOL OF ENGINEERING AND APPLIED SCIENCE
The formation, interaction and collapse of nonlinear Langmuir waves in plasmas have been studied extensively in recent years. In most of the existing works, attention is focused primarily on the formation and interaction of solitary waves. Exact expressions for these solitary waves for various regimes have been obtained only for the one-dimensional case. Recently, the possibility of existence of solitary Langmuir waves for higher dimensions was discussed. This study obtains conditions for the existence or nonexistence of multidimensional, nonlinear Langmuir travelling waves, including the periodic and the usual solitary waves.