The sharp exponent in the study of the nonlocal Hénon equation in $\mathbb{R}^{n}$. A Liouville theorem and an existence result

Abstract

We will consider the nonlocal Hénon equation $$(-Δ)^s u= |x|^α u^{p},\quad \mathbb{R}^{N},$$ where $(-Δ)^s$ is the fractional Laplacian operator with $0 1$ and $N>2s$. We prove a nonexistence result for positive solutions in the optimal range of the nonlinearity, that is, when $$1<p<p^*_{α, s}:=\frac{N+2α+2s}{N-2s}.$$ Moreover, we prove that a bubble solution, that is a fast decay positive radially symmetric solutions, exists when $p=p_{α, s}^{*}$.