A note on preconditioner for the Ohta-Kawasaki equation

In this paper, an efficient preconditioner is proposed for the discrete Ohta-Kawasaki system. We show that the eigenvalues of the new preconditioned matrix are the same as that of the recently published block triangular preconditioner in [P. E. Farrell, J. W. Pearson, SIAM J. Matrix Anal. Appl. 38(1) (2017) 217-225]. Numerical experiments are presented to illustrate the effectiveness and feasibility of the new preconditioner to accelerate GMRES method.