Qualitative properties of single blow-up solutions for nonlinear Hartree equation with slightly subcritical exponent
Alessandro Cannone, Silvia Cingolani, Minbo Yang, Shunneng Zhao
TL;DR
The paper analyzes the qualitative structure of single blow-up solutions to the nonlocal Hartree equation with slightly subcritical exponent on bounded domains in dimensions 3–5. By combining local Pohozaev identities with blow-up analysis, it derives precise asymptotics for the first (n+2) eigenpairs of the linearized operator and connects these to the Robin function and Green's function, revealing how curvature of φ governs Morse index through the Hessian eigenvalues. The results show the first eigenvalue converges to a subcritical limit, the next n+1 eigenvalues approach 1 with Hessian-determined corrections, and the (n+2)-th eigenvalue exhibits a distinct asymptotic tied to a two-region nodal structure; together, they yield explicit Morse-index relations and a nondegenerate blow-up behavior. This work extends local results to a nonlocal Hartree setting, highlighting the interplay between nonlocal nonlinearities, blow-up profiles, and spectral stability via Robin-function geometry, with potential implications for stability analysis of singular solutions in nonlocal elliptic problems.
Abstract
In this paper, we study the qualitative properties of single blow-up solutions to the nonlocal equations with slightly subcritical exponents \begin{equation*} -Δu=(|x|^{-(n-2)}\ast u^{p-ε})u^{p-1-ε}\quad \mbox{in}~~Ω,~~ u=0\quad \mbox{on}~~\partialΩ, \end{equation*} where $Ω$ is a smooth bounded domain in $\mathbb{R}^n$ for $n=3,4,5$, $\ast$ denotes the standard convolution, $ε>0$ is a small parameter and $p=\frac{n+2}{n-2}$ is $\mathcal{D}^{1,2}$ energy-critical exponent. By exploiting various local Pohozaev identities and blow-up analysis, we provide a number of estimates on the first $(n+2)$-eigenvalues and their corresponding eigenfunctions, and examine the qualitative behavior of the eigenpairs $(λ_{i,ε}, v_{i,ε})$ to the linearied problem of the above nonlocal equations for $i=1,\cdots,n+2$. As a corollary, we derive the Morse index of a single-bubble solution in a nondegenerate setting.
