Sparse formulae for the distance modulus in cosmology

Lorenzo Zaninetti

doi:10.4236/jhepgc.2021.73057

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arXiv · 2107.12140

Sparse formulae for the distance modulus in cosmology

Lorenzo Zaninetti

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Abstract

We review the distance modulus in twelve different cosmologies: the $\Lambda$CDM model, the wCDM model, the Cardassian model, the flat case, the $\phi$CDM cosmology, the Einstein--De Sitter model, the modified Einstein--De Sitter model, the simple~GR model, the flat expanding model, the Milne model, the plasma model and the modified tired light model. The above distance moduli are processed for three different compilations of supernovae and a supernovae + GRBs compilation: Union 2.1, JLA, the Pantheon and Union 2.1 + 59 GRBs. For each of the 48 analysed cases we report the relative cosmological parameters, the chi-square, the reduced chi-square, the AIC and the $Q$ parameter. The angular distance as function of the redshift for five cosmologies is reported in the framework of the minimax approximation.

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Lorenzo Zaninetti. 2021-07-10. Sparse formulae for the distance modulus in cosmology. https://doi.org/10.4236/jhepgc.2021.73057

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