Uniqueness and concentration for a fractional Kirchhoff problem with strong singularity

Abstract

AbstractIn this paper, we consider the following fractional Kirchhoff problem with strong singularity: $$ \textstyle\begin{cases} (1+ b\int _{\mathbb{R}^{3}}\int _{\mathbb{R}^{3}} \frac{ \vert u(x)-u(y) \vert ^{2}}{ \vert x-y \vert ^{3+2s}}\,\mathrm{d}x \,\mathrm{d}y )(-\Delta )^{s} u+V(x)u = f(x)u^{-\gamma }, & x \in \mathbb{R}^{3}, \\ u>0,& x\in \mathbb{R}^{3}, \end{cases} $$ { ( 1 + b ∫ R 3 ∫ R 3 | u ( x ) − u ( y ) | 2 | x − y | 3 + 2 s d x d y ) ( − Δ ) s u + V ( x ) u = f ( x ) u − γ , x ∈ R 3 , u > 0 , x ∈ R 3 , where $(-\Delta )^{s}$ ( − Δ ) s is the fractional Laplacian with $0< s<1$ 0 < s < 1 , $b>0$ b > 0 is a constant, and $\gamma >1$ γ > 1 . Since $\gamma >1$ γ > 1 , the energy functional is not well defined on the work space, which is quite different with the situation of $0<\gamma <1$ 0 < γ < 1 and can lead to some new difficulties. Under certain assumptions on V and f, we show the existence and uniqueness of a positive solution $u_{b}$ u b by using variational methods and the Nehari manifold method. We also give a convergence property of $u_{b}$ u b as $b\rightarrow 0$ b → 0 , where b is regarded as a positive parameter.