International Journal of Mathematics and Mathematical Sciences
Volume 9 (1986), Issue 3, Pages 531-540
doi:10.1155/S0161171286000662

Space-time caustics

Abstract

The Lagrange manifold (WKB) formalism enables the determination of the asymptotic series solution of linear differential equations modelling wave propagation in spatially inhomogeneous media at caustic (turning) points. Here the formalism is adapted to determine a class of asymptotic solutions at caustic points for those equations modelling wave propagation in media with both spatial and temporal inhomogeneities. The analogous Schrodinger equation is also considered.