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arXiv · 1411.7692

Non-local gravity and comparison with observational datasets

Yves Dirian·Stefano Foffa·Martin Kunz·Michele Maggiore·Valeria Pettorino
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Abstract

We study the cosmological predictions of two recently proposed non-local modifications of General Relativity. Both models have the same number of parameters as $Λ$CDM, with a mass parameter $m$ replacing the cosmological constant. We implement the cosmological perturbations of the non-local models into a modification of the CLASS Boltzmann code, and we make a full comparison to CMB, BAO and supernova data. We find that the non-local models fit these datasets as well as $Λ$CDM. For both non-local models parameter estimation using Planck+JLA+BAO data gives a value of $H_0$ higher than in $Λ$CDM, and in better agreement with the values obtained from local measurements.

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Yves Dirian, Stefano Foffa, Martin Kunz, Michele Maggiore, Valeria Pettorino. 2014-11-27. Non-local gravity and comparison with observational datasets. https://doi.org/10.1088/1475-7516%2F2015%2F04%2F044

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