“…The fractional differential operator (−∆) s is defined by (−∆) s u = F −1 [|ξ| 2s F(u)], where F and F −1 are the Fourier transform and inverse Fourier transform, respectively. Recently, equation (1.1) has attracted more and more attentions in both the physics and mathematics fields, see [2,3,7,9,12,13,14,15,16,19,20,21,26,23,24,25,30,32,35,47,48,49]. For the Hartree-type nonlinearity f (u) = ±(|x| −γ * |u| 2 )u, Cho et al in [8] proved existence and uniqueness of local and global solutions of (1.1).…”