Effect of limited resolution on the power spectrum. The solid curves show the power spectrum measured from simulation C, a PM simulation with the same number of particles as simulation A, a P³M simulation. The spectra are computed on a 512³ grid and are shown at the same output times as those of Figure 1. The dotted curves show the spectra from simulation A, computed using a 1024³ grid. Both spectra are plotted up to ﹩\frac{1}{2}﹩ the Nyquist frequency of the FFT grid. A comparison of the two sets of spectra shows that as time evolves, the power in the PM simulation is suppressed on an increasingly large range of k.