Periodic Response Solutions to Multi-Dimensional Nonlinear Schrödinger equation with unbounded perturbation
Zuhong You, Xiaoping Yuan
TL;DR
This work addresses the problem of obtaining time-periodic solutions to the multi-dimensional nonlinear Schrödinger equation with unbounded fractional-derivative perturbations by applying the Craig–Wayne–Bourgain (CWB) method. The authors construct an initial approximate solution and iteratively correct it via a Newton scheme, carefully controlling the associated linearized (Green) operators on shrinking Cantor-like parameter sets. Central to the analysis are sharp Green-function estimates, achieved through a multi-scale scheme and coupling lemmas, which ensure exponential off-diagonal decay and bounded inverse norms. The results yield a Gevrey-smooth, $\frac{2\pi}{\omega}$-periodic solution for most frequencies $\omega$ in $[1,2]$ with precise quantitative smallness of the residual and Fourier coefficients, providing a step toward understanding unbounded perturbations in higher-dimensional NLS contexts.
Abstract
By applying the Craig-Wayne-Bourgain (CWB) method, we establish the existence of periodic response solutions to multi-dimensional nonlinear Schrödinger equations (NLS) with unbounded perturbation.
