ASA 124th Meeting New Orleans 1992 October

1pUW9. Does ray chaos in range-dependent environments disappear when higher-order approximations are made?

Martin A. Mazur

Appl. Res. Lab., P.O. Box 30, State College, PA 16804

Recent work has shown that when range dependence, in either the index of refraction or the boundary conditions, is introduced into the infinite frequency (ray) approximation to the wave equation, ray chaos results. This is because the resulting conservative system of ordinary differential equations is nonlinear and nonintegrable. Attempts have been made to reconcile chaotic ray behavior with the fact that chaotic solutions of the full linear wave equation cannot exist. When the terms neglected in making the eikonal approximation are kept, the resulting system of equations is generally no longer conservative, and hence chaos is not a necessary result of the higher-order approximation. [Work supported by ONR.]