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arXiv · 2011.03957

Analyzing the $H_0$ tension in $F(R)$ gravity models

Sergei D. Odintsov·Diego Sáez-Chillón Gómez·German S. Sharov
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Abstract

The Hubble constant tension problem is analysed in the framework of a class of modified gravity, the so-called $F(R)$ gravity. To do so, we explore two models: an exponential and a power-law $F(R)$ gravities, which includes an early dark energy (EDE) term in the latter. These models can describe both an early time inflationary epoch and the late time accelerating expansion of the universe. We confront both models with recent observational data including the Pantheon Type Ia supernovae sample, the latest measurements of the Hubble parameter $H(z)$ from differential ages of galaxies (cosmic chronometers) and separately from baryon acoustic oscillations. Standard rulers data set from the Cosmic Microwave Background radiation are also included in our analysis. The estimations of the Hubble constant appear to be essentially depending on the set of observational data and vary in the range from 68 to 70{.}3 km\,/(s$\cdot$Mpc). The fits of the other free parameters of the models are also obtained, revealing interesting consequences.

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Sergei D. Odintsov, Diego Sáez-Chillón Gómez, German S. Sharov. 2020-11-08. Analyzing the $H_0$ tension in $F(R)$ gravity models. https://doi.org/10.1016/j.nuclphysb.2021.115377

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