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arXiv · 0911.5396

Non-linear Matter Spectra in Coupled Quintessence

F. Saracco·M. Pietroni·N. Tetradis·V. Pettorino·G. Robbers
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Abstract

We consider cosmologies in which a dark-energy scalar field interacts with cold dark matter. The growth of perturbations is followed beyond the linear level by means of the time-renormalization-group method, which is extended to describe a multi-component matter sector. Even in the absence of the extra interaction, a scale-dependent bias is generated as a consequence of the different initial conditions for baryons and dark matter after decoupling. The effect is enhanced significantly by the extra coupling and can be at the 2-3 percent level in the range of scales of baryonic acoustic oscillations. We compare our results with N-body simulations, finding very good agreement.

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F. Saracco, M. Pietroni, N. Tetradis, V. Pettorino, G. Robbers. 2014-04-10. Non-linear Matter Spectra in Coupled Quintessence. https://doi.org/10.1103/physrevd.82.023528

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