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arXiv · 0903.4693

Rejuvenating the matter power spectrum: restoring information with a logarithmic density mapping

Mark C. Neyrinck·István Szapudi·Alexander S. Szalay
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Abstract

We find that nonlinearities in the dark-matter power spectrum are dramatically smaller if the density field first undergoes a logarithmic mapping. In the Millennium simulation, this procedure produces a power spectrum with a shape hardly departing from the linear power spectrum for k <~ 1 h/Mpc at all redshifts. Also, this procedure unveils pristine Fisher information on a range of scales reaching a factor of 2-3 smaller than in the standard power spectrum, yielding 10 times more cumulative signal-to-noise at z=0.

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Mark C. Neyrinck, István Szapudi, Alexander S. Szalay. 2009-05-18. Rejuvenating the matter power spectrum: restoring information with a logarithmic density mapping. https://doi.org/10.1088/0004-637x%2F698%2F2%2Fl90

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