English

On nonlinear effects in multiphase WKB analysis for the nonlinear Schrodinger equation

Analysis of PDEs 2025-07-23 v3 Mathematical Physics math.MP

Abstract

We consider the Schrodinger equation with an external potential and a cubic nonlinearity, in the semiclassical limit. The initial data are sums of WKB states, with smooth phases and smooth, compactly supported initial amplitudes, with disjoint supports. We show that like in the linear case, a superposition principle holds on some time interval independent of the semiclassical parameter, in several regimes in term of the size of initial data with respect to the semiclassical parameter. For large data, we invoke properties of compressible Euler equations. For smaller data, we show that there may be no nonlinear interferences on some time interval independent of the semiclassical parameter, and interferences for later time, thanks to explicit computations available for particular phases.

Keywords

Cite

@article{arxiv.2309.03597,
  title  = {On nonlinear effects in multiphase WKB analysis for the nonlinear Schrodinger equation},
  author = {Remi Carles},
  journal= {arXiv preprint arXiv:2309.03597},
  year   = {2025}
}

Comments

The version was uploaded on Hal on November 29, but failed to be forwarded to arXiv. Restatement of the main results (abstract changed), more explanations, generalized setting

R2 v1 2026-06-28T12:15:08.776Z