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arXiv · astro-ph/0611284

Some impacts of quintessence models on cosmic structure formation

Abstract

Some physical imprints of quintessence scalar fields on dark matter (DM) clustering are illustrated, and a comparison with the concordance model $ΛCDM$ is highlighted. First, we estimate the cosmological parameters for two quintessence models, based on scalar fields rolling down the Ratra-Peebles or Sugra potential, by a statistical analysis of the Hubble diagram of type Ia supernovae. Then, the effect of these realistic dark energy models on large-scale DM clustering is established through N-body simulations. Various effects like large-scale distribution of DM, cluster mass function and halos internal velocities are illustrated. It is found that realistic dark energy models lead to quite different DM clustering, due to a combination of the variation of the equation of state and differences in the cosmological parameters, even at $z=0$. This conclusion contradicts other works in the recent litterature and the importance of considering more realistic models in studying the impact of quintessence on structure formation is highlighted.

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BibTeXRIS

A. Fuzfa J. -M. Alimi. 2006-11-09. Some impacts of quintessence models on cosmic structure formation. https://doi.org/10.1063/1.2399670

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