A singularly perturbed fractional Kirchhoff problem

TL;DR

This paper proves the uniqueness and non-degeneracy of positive solutions to a fractional Kirchhoff problem and uses these results to establish the existence of semiclassical solutions for a perturbed version with a potential.

Contribution

It introduces new uniqueness and non-degeneracy results for fractional Kirchhoff problems and applies Lyapunov-Schmidt reduction to find semiclassical solutions.

Findings

Proved uniqueness of positive solutions.

Established non-degeneracy of solutions.

Derived existence of semiclassical solutions for small perturbations.

Abstract

In this paper, we first establish the uniqueness and non-degeneracy of positive solutions to the fractional Kirchhoff problem \begin{equation*} \Big(a+b{\int_{\mathbb{R}^{N}}}|(-\Delta)^{\frac{s}{2}}u|^2dx\Big)(-\Delta)^su+mu=|u|^{p-2}u,\quad \text{in}\ \mathbb{R}^{N}, \end{equation*} where $a,b,m>0$, $0<\frac{N}{4}<s<1$, $2<p<2^*_s=\frac{2N}{N-2s}$ and $(-\Delta )^s$ is the fractional Laplacian. Then, combining this non-degeneracy result and Lyapunov-Schmidt reduction method, we derive the existence of semiclassical solutions to the singularly perturbation problem \begin{equation*} \Big(\varepsilon^{2s}a+\varepsilon^{4s-N} b{\int_{\mathbb{R}^{N}}}|(-\Delta)^{\frac{s}{2}}u|^2dx\Big)(-\Delta)^su+V(x)u=|u|^{p-2}u,\quad \text{in}\ \mathbb{R}^{N}, \end{equation*} for $\varepsilon> 0$ sufficiently small and a potential function $V$.