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Emergent Dark Energy, neutrinos and cosmological tensions

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 Added by Supriya Pan
 Publication date 2020
  fields Physics
and research's language is English




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The Phenomenologically Emergent Dark Energy model, a dark energy model with the same number of free parameters as the flat $Lambda$CDM, has been proposed as a working example of a minimal model which can avoid the current cosmological tensions. A straightforward question is whether or not the inclusion of massive neutrinos and extra relativistic species may spoil such an appealing phenomenological alternative. We present the bounds on $M_{ u}$ and $N_{rm eff}$ and comment on the long standing $H_0$ and $sigma_8$ tensions within this cosmological framework with a wealth of cosmological observations. Interestingly, we find, at $95%$ confidence level, and with the most complete set of cosmological observations, $M_{ u}sim 0.21^{+0.15}_{-0.14}$ eV and $N_{rm eff}= 3.03pm 0.32$ i.e. an indication for a non-zero neutrino mass with a significance above $2sigma$. The well known Hubble constant tension is considerably easened, with a significance always below the $2sigma$ level.



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