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arXiv · 2302.09777

Data-driven and Almost Model-independent Reconstruction of Modified Gravity

Yuhao Mu·En-Kun Li·Lixin Xu
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Abstract

In this paper, a modified factor $\mu$, which characterizes modified gravity in the linear matter density perturbation theory, is reconstructed in a data-driven and almost model-independent way via Gaussian process by using currently available cosmic observations. Utilizing the Pantheon+ SNe Ia samples, the observed Hubble parameter $H(z)$ and the redshift space distortion $f\sigma_8(z)$ data points, one finds out a time varying $\mu$ at low redshifts. The reconstructed $\mu$ implies that more complicated modified gravity beyond the simplest general relativity and the Dvali-Gabadadze-Porrati braneworld model is required.

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Yuhao Mu, En-Kun Li, Lixin Xu. 2023-02-20. Data-driven and Almost Model-independent Reconstruction of Modified Gravity. https://doi.org/10.1088/1475-7516/2023/06/022

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