Singular Levy processes and dispersive effects of generalized Schr\"odinger equations

TL;DR

This paper introduces generalized Schr"odinger equations with direction-dependent dispersion, unifies previous models, and proves large data scattering on waveguide manifolds, extending understanding of dispersive effects in mathematical physics.

Contribution

It develops new models for Schr"odinger equations with anisotropic dispersion and proves large data scattering results on waveguide manifolds, extending prior work and unifying various models.

Findings

Established large data scattering on waveguide manifolds $\\mathbb{R}^d \times \mathbb{T}$ for $d \geq 3$.

Unified several previous results into a natural framework.

Proved a Morawetz-type estimate for the new models.

Abstract

We introduce new models for Schr\"odinger-type equations, which generalize standard NLS and for which different dispersion occurs depending on the directions. Our purpose is to understand dispersive properties depending on the directions of propagation, in the spirit of waveguide manifolds, but where the diffusion is of different types. We mainly consider the standard Euclidean space and the waveguide case but our arguments extend easily to other types of manifolds (like product spaces). Our approach unifies in a natural way several previous results. Those models are also generalizations of some appearing in seminal works in mathematical physics, such as relativistic strings. In particular, we prove the large data scattering on waveguide manifolds $\mathbb{R}^d \times \mathbb{T}$, $d \geq 3$. This result can be regarded as the analogue of \cite{TV2, YYZ2} in our setting and the waveguide analogue investigated in \cite{GSWZ}. A key ingredient of the proof is a Morawetz-type estimate for the setting of this model.