In this paper, we investigate the global existence of weak solutions to 3-D inhomogeneous incompressible MHD equations with variable viscosity and resistivity, which is sufficiently close to 1 in L^ (R³), provided that the initial density is bounded from above and below by positive constants, and both the initial velocity and magnetic field are small enough in the critical space Ḣ^1{2} (R³). Furthermore, if we assume in addition that the kinematic viscosity equals 1, and both the initial velocity and magnetic field belong to Ḃ^1{2}₂, ₁ (R³), we can also prove the uniqueness of such solution.
Abidi et al. (Sat,) studied this question.