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arXiv · 2011.00283

Interacting Dark Energy in a closed universe

Eleonora Di Valentino·Alessandro Melchiorri·Olga Mena·Supriya Pan·Weiqiang Yang
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Abstract

Recent measurements of the Cosmic Microwave Anisotropies power spectra measured by the Planck satellite show a preference for a closed universe at more than $99 \%$ Confidence Level. Such a scenario is however in disagreement with several low redshift observables, including luminosity distances of Type Ia Supernovae. Here we show that Interacting Dark Energy (IDE) models can ease the discrepancies between Planck and Supernovae Ia data in a closed Universe. Therefore IDE cosmologies remain as very appealing scenarios, as they can provide the solution to a number of observational tensions in different fiducial cosmologies. The results presented here strongly favour broader analyses of cosmological data, and suggest that relaxing the usual flatness and vacuum energy assumptions can lead to a much better agreement among theory and observations.

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Eleonora Di Valentino, Alessandro Melchiorri, Olga Mena, Supriya Pan, Weiqiang Yang. 2020-10-31. Interacting Dark Energy in a closed universe. https://doi.org/10.1093/mnrasl%2Fslaa207

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