Existence of infinitely many solutions for a nonlocal elliptic PDE involving singularity

In this article, we will prove the existence of infinitely many positive weak solutions to the following nonlocal elliptic PDE. \begin{align} (-\Delta)^s u&= \frac{\lambda}{u^{\gamma}}+ f(x,u)~$\text{in}$~\Omega,\nonumber u&=0~$\text{in}$~$\mathbb{R}$^N\setminus\Omega,\nonumber \end{align} where $\mathrm{\Omega }$ is an open bounded domain in ${\mathbb{R}}^N$ with Lipschitz boundary, $N>2s$, $s\in (0,1)$, $\gamma \in (0,1)$. We will employ variational techniques to show the existence of infinitely many weak solutions of the above problem.