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arXiv · 1302.4830

The radiation energy component of the Hubble function and a LCDM cosmological simulation

Hector Aceves
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Abstract

We study some effects the inclusion of the radiation energy component in the universe, Omega_r, can have on several quantities of interest for the large-scale structure of the universe in a LCDM cosmological simulation; started at a very high redshift (z=500). In particular we compute the power spectrum density, the halo mass function, and the concentration-mass relation for haloes. We find that Omega_r has an important contribution in the long-term nonlinear evolution of structures in the universe. For instance, a lower matter density power, by approx 50%, in all scales is obtained when compared with a simulation without the radiation term. Also, haloes formed with the Omega_r taken into account are approx 20% less concentrated than when not included in the Hubble function.

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Hector Aceves. 2013-02-20. The radiation energy component of the Hubble function and a LCDM cosmological simulation. https://arxiv.org/abs/1302.4830

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