Precision cosmology made more precise

2021/02/02 by Galanti, Giorgio, Roncadelli, Marco
#Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences

paper · doi:10.48550/arxiv.2102.01637

Abstract

So far, the standard attitude to solve the Friedmann equations in the simultaneous presence of radiation R, matter M and cosmological constant Λ is to find solutions R_R (t), R_M (t) and R_Λ (t) separately for each individual component alone, and next to join them together, thereby obtaining a piecewise solution R_{\rm pw} (t). We instead find the exact and analytic solution R (t) of the same equations in flat space. Moreover, we quantify the error made when R_{\rm pw} (t) is used in place of R (t).

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