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arXiv · 2003.04935

Investigating Cosmic Discordance

Eleonora Di Valentino·Alessandro Melchiorri·Joseph Silk
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Abstract

We show that a combined analysis of CMB anisotropy power spectra obtained by the Planck satellite and luminosity distance data simultaneously excludes a flat universe and a cosmological constant at $99 \%$ CL. These results hold separately when combining Planck with three different datasets: the two determinations of the Hubble constant from Riess et al. 2019 and Freedman et al. 2020, and the Pantheon catalog of high redshift supernovae type-Ia. We conclude that either LCDM needs to be replaced by a different model, or else there are significant but still undetected systematics. Our result calls for new observations and stimulates the investigation of alternative theoretical models and solutions.

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Eleonora Di Valentino, Alessandro Melchiorri, Joseph Silk. 2020-03-10. Investigating Cosmic Discordance. https://doi.org/10.3847/2041-8213%2Fabe1c4

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