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arXiv · 2304.03261

Note on agegraphic dark energy inspired by modified Barrow entropy

A. Sheykhi·S. Ghaffari
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Abstract

We revisit agegraphic dark energy (ADE) model when the entropy associated with the apparent horizon is in the form of Barrow entropy, $S\sim A^{1+\delta/2}$, where $0\leq\delta\leq1$ indicates the amount of the quantum-gravitational deformation effects of the horizon. The modification to the entropy expression, not only change the energy density of ADE, but also modifies the Friedmann equations due to thermodynamics-gravity conjecture. Based on this, we investigate the cosmological consequences of ADE through modified Barrow cosmology and disclose the effects of Barrow exponent $\delta$ on the evolutions of the cosmological parameters. We observe that, depending on the values of $\delta$, the transition from early decelerated phase to the late time accelerated phase occurs, and the equation of state (EoS) parameter $ w_{de} $ varies from quintessence $ -1<w_{de}<-1/3 $ to the phantom regime $ (w_{de}<-1)$. When $\delta=0$, all results of ADE in standard cosmology are restored.

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A. Sheykhi, S. Ghaffari. 2023-04-06. Note on agegraphic dark energy inspired by modified Barrow entropy. https://doi.org/10.1016/j.dark.2023.101241

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