Nodal bubble tower solutions to slightly subcritical elliptic problems with Hardy terms

TL;DR

This paper constructs complex nodal bubble tower solutions for a slightly subcritical elliptic problem with Hardy potential, revealing detailed blow-up behaviors as parameters approach zero.

Contribution

It introduces the first known existence of nodal bubble tower solutions with multiple blow-up orders at the same point in a Hardy elliptic problem.

Findings

Existence of nodal bubble tower solutions with multiple blow-up orders

Solutions blow up at the origin with different rates

Behavior characterized as parameters tend to zero

Abstract

We study the possible blow-up behavior of solutions to the slightly subcritical elliptic problem with Hardy term \[ \left\{ \begin{aligned} -\Delta u-\mu\frac{u}{|x|^2} &= |u|^{2^{\ast}-2-\varepsilon}u &&\quad \text{in } \Omega, \\\ u &= 0&&\quad \text{on } \partial\Omega, \end{aligned} \right. \] in a bounded domain $\Omega\subset\mathbb{R}^N (N\ge7)$ with $0\in\Omega$, as $\mu,\varepsilon\to 0^+$. In \cite{BarGuo-ANS}, we obtained the existence of nodal solutions that blow up positively at the origin and negatively at a different point as $\mu=O(\epsilon^\alpha)$ with $\alpha>\frac{N-4}{N-2}$, $\varepsilon\to 0^+$. Here we prove the existence of nodal bubble tower solutions, i.e.\ superpositions of bubbles of different signs, all blowing up at the origin but with different blow-up order, as $\mu=O(\varepsilon)$, $\varepsilon\to0^+$.