On well-posedness for inhomogeneous Hartree equations in the critical case

TL;DR

This paper advances the understanding of the well-posedness of the inhomogeneous Hartree equation in the critical Sobolev space range, including energy-critical cases, by employing Sobolev-Lorentz spaces for finer analysis of singularities.

Contribution

It develops a new well-posedness theory for the inhomogeneous Hartree equation in the critical Sobolev space range, especially for the energy-critical case, using Sobolev-Lorentz spaces.

Findings

Established well-posedness in the case 1/2 ≤ s ≤ 1.

Included the energy-critical case in the analysis.

Utilized Sobolev-Lorentz spaces for finer control of singularities.

Abstract

We study the well-posedness for the inhomogeneous Hartree equation $i\partial_t u + \Delta u = \lambda(I_\alpha \ast |\cdot|^{-b}|u|^p)|x|^{-b}|u|^{p-2}u$ in $H^s$, $s\ge0$. Until recently, its well-posedness theory has been intensively studied, focusing on solving the problem for the critical index $p=1+\frac{2-2b+\alpha}{n-2s}$ with $0\le s \le 1$, but the case $1/2\leq s \leq 1$ is still an open problem. In this paper, we develop the well-posedness theory in this case, especially including the energy-critical case. To this end, we approach to the matter based on the Sobolev-Lorentz space which can lead us to perform a finer analysis for this equation. This is because it makes it possible to control the nonlinearity involving the singularity $|x|^{-b}$ as well as the Riesz potential $I_\alpha$ more effectively.