微扰技术用于大振幅驻波理论

微扰技术（即逐步求近法）曾误用于大振幅驻波理论数十年，给出可疑的、不稳定结果.究其原因是前人在解非线性波动方程时，未能始终贯彻驻波基本性质所致.始终坚持驻波观点完全可以求得稳定解，与根据Riemann简单波所得严格解一致.这个问题说明，物理学家使用数学工具时，必须在物理原则指导下进行。

Perturbation technique in theory of nonlinear standing waves

Perturbation teclmique has been disused in the theory of nonlinear standing waves for tens of years, with consequence of questionable, unstable results. The reason is that these earlier authors did not stick to the fundamental properties of standing waves in their mathematical treatments. Stable solutions result,agreeing with the exact theory of nonlinear standing waves, once the standing wave viewpoint is stressed throughout the derivation. This suggests that principles of physics must be used to direct the mathematical manipulation closely in solving a problem of physics.