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Best median values for cosmological parameters

Matts Roos
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Abstract

Our procedure to obtain best values for cosmological parameters from five recent multiparameter fits is as follows. We first study the values quoted for $r, α_s, w+1 (w_0+1), w_1$ and $Ω_k$, arriving at the conclusion that they do not differ significantly from zero, and their correlations to other parameters are insignificant. In what follows they can be therefore fixed. The neutrino mass sum $Σm_ν$ also does not differ significantly from zero, but since neutrinos are massive their sum must be included as a free parameter. We then compare the values obtained in five large flat-space determinations of the parameters $Σm_ν, ω_b, ω_m, h, τ, n_s, A_s$ and $σ_8$. For these we compute the medians and the 17-percentile and 83-percentile errors by a described procedure.

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Matts Roos. 2006-03-13. Best median values for cosmological parameters. https://arxiv.org/abs/astro-ph/0509089

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