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Information content of the non-linear matter power spectrum

C. D. Rimes·A. J. S. Hamilton
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Abstract

We use an ensemble of N-body simulations of the currently favoured (concordance) cosmological model to measure the amount of information contained in the non-linear matter power spectrum about the amplitude of the initial power spectrum. Two surprising results emerge from this study: (i) that there is very little independent information in the power spectrum in the translinear regime (k ~ 0.2-0.8 Mpc/h at the present day) over and above the information at linear scales and (ii) that the cumulative information begins to rise sharply again with increasing wavenumber in the non-linear regime. In the fully non-linear regime, the simulations are consistent with no loss of information during translinear and non-linear evolution. If this is indeed the case then the results suggest a picture in which translinear collapse is very rapid, and is followed by a bounce prior to virialization, impelling a wholesale revision of the HKLM-PD formalism.

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C. D. Rimes, A. J. S. Hamilton. 2005-04-12. Information content of the non-linear matter power spectrum. https://doi.org/10.1111/j.1745-3933.2005.00051.x

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