Existence of sign-changing solution for a problem involving the fractional Laplacian with critical growth nonlinearities

We study the existence of least energy sign-changing solution for the fractional equation $(-\Delta)^{s} u=|u|^{2_{s}^{*}-2}u+\lambda f(x,u)$ in a smooth bounded domain $\Omega$ of $\mathbb{R}^{N},$ $u=0$ in $\mathbb{R}^{N}\setminus \Omega$, where $s\in (0,1)$ and $2_{s}^{*}$ is the fractional critical Sobolev exponent. The proof is based on constrained minimization in a subset of Nehari manifold, containing all the possible sign-changing solutions of the equation.