Information content in the halo-model dark-matter power spectrum - II. Multiple cosmological parameters

We investigate the cosmological Fisher information in the non- linear dark matter power spectrum in the context of the halo model. We find that there is a plateau in information content on translinear scales which is generic to all cosmological parameters we tried. There is a rise in information on smaller scales, but we find that it is quite degenerate among different cosmological parameters ( except, perhaps, the tilt). This suggests that it could be difficult to constrain cosmological parameters using the non- linear regime of the dark- matter power spectrum. We suggest ways to get around this problem, such as removing the largest haloes from consideration in survey analysis.