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Information content in the halo-model dark-matter power spectrum

Mark C. Neyrinck·István Szapudi·Christopher D. Rimes
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Abstract

Using the halo model, we investigate the cosmological Fisher information in the non-linear dark-matter power spectrum about the initial amplitude of linear power. We find that there is little information on `translinear' scales (where the one- and two-halo terms are both significant) beyond what is on linear scales, but that additional information is present on small scales, where the one-halo term dominates. This behavior agrees with the surprising results that Rimes & Hamilton (2005, 2006) found using N-body simulations. We argue that the translinear plateau in cumulative information arises largely from fluctuations in the numbers of large haloes in a finite volume. This implies that more information could be extracted on non-linear scales if the masses of the largest haloes in a survey are known.

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Mark C. Neyrinck, István Szapudi, Christopher D. Rimes. 2006-05-11. Information content in the halo-model dark-matter power spectrum. https://doi.org/10.1111/j.1745-3933.2006.00190.x

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