ABSTRACT
This chapter discusses the grid methods which relate the individual discrete spatial coordinates for computational efficiency. It explains that how the physical properties of a simulation plasma are modified by the presence of a spatial grid. The chapter shows that interactions through the grids couple a perturbation to perturbations at other wavelengths called aliases. The significance of this coupling is limited if finite size particles are used, and if the spacing between some adjacent grid points is about the Debye length. The grid accumulates charge and from particles on the grid, converts the change and current into forces on the grid, and applies these forces at the grid points on the individual particles. The area weighting scheme assigns a fraction of charge of a particle to respective grid points according to the relative weight which the particle distributes to the adjacent grid points.
