Several recent results in nonlinear geometric optics
Many recent works are devoted to the study of high frequency oscillatory nonlinear waves, and to nonlinear geometric optics. Typical questions are the existence, the propagation, the interaction and the reflection of waves of the form ::: ::: $$ {u^\varepsilon }\left( {t,x} \right) \sim \underline u \left( {t,x} \right) + {\varepsilon ^\alpha }\sum\limits_{n0} {{\varepsilon ^n}} {U_n}\left( {t,x,\varphi \left( {t,x} \right)/\varepsilon } \right). $$ ::: ::: (1.1)
4 pages.-- PACS numbers: 05.45.Xt, 87.10.+e.-- ArXiv pre-print: http://arxiv.org/abs/nlin.CD/0512009.-- Final full-text version of the paper available at: http://dx.doi.org/10.1103/PhysRevE.73.055202.