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arXiv · 2211.04178

An attempt to add Barrow entropy in $f(R)$ gravity

P. S. Ens·A. F. Santos
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Abstract

In this work, a way to consider together two originally different corrections to the Friedmann equations is presented. The first is the Barrow entropy, which imposes a fractal structure on the black hole horizon area. While the second is the well-known $f(R)$ gravity, which comes from a generalization of the Einstein-Hilbert action. Using the ideas of gravity-thermodynamics conjecture, these two models are combined. Then the modified Friedmann equation is obtained. Choosing a particular $f(R)$ model, an application is investigated. The state parameter and the density parameters for matter and dark energy are calculated. With these results, the dynamic evolution of the universe is discussed.

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P. S. Ens, A. F. Santos. 2022-11-08. An attempt to add Barrow entropy in $f(R)$ gravity. https://doi.org/10.1016/j.physletb.2022.137562

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