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arXiv · 1906.05991

Defying the laws of Gravity I: model-independent reconstruction of the Universe expansion from growth data

Benjamin L'Huillier·Arman Shafieloo·David Polarski·Alexei A. Starobinsky
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Abstract

Using redshift space distortion data, we perform model-independent reconstructions of the growth history of matter inhomogeneity in the expanding Universe using two methods: crossing statistics and Gaussian processes. We then reconstruct the corresponding history of the Universe background expansion and fit it to type Ia supernovae data, putting constraints on $(\Omega_\mathrm{m,0},\sigma_{8,0})$. The results obtained are consistent with the concordance flat-$\Lambda$CDM model and General Relativity as the gravity theory given the current quality of the inhomogeneity growth data.

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Benjamin L'Huillier, Arman Shafieloo, David Polarski, Alexei A. Starobinsky. 2019-06-14. Defying the laws of Gravity I: model-independent reconstruction of the Universe expansion from growth data. https://doi.org/10.1093/mnras%2Fstaa633

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