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arXiv · 2501.03655

$Λ$CDM Model Against Gravity-Thermodynamics Conjecture: Observational Constraints After DESI 2024

N. Shahhoseini·M. Malekjani·A. Khodam-Mohammadi
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Abstract

In the context of the gravity-thermodynamics conjecture based on the Tsallis entropy-area relation, we investigate the standard $Λ$CDM cosmology and examine some potential deviations from it. Utilizing recent updates from geometrical datasets, including the DESI BAO measurements (2024), Planck CMB anisotropy measurements (2018), and the Pantheon+ catalogue for SNIa (2022), we conduct a thorough analysis via the window of Tsallis cosmology. In the first step, our analysis reveals no significant deviation from the standard model when using DESI BAO data alone, Pantheon+ data alone, or a combination of both. In the next step, we incorporate all datasets by adding the CMB data to our analysis, indicating a potential deviation from the standard model within the framework of Tsallis cosmology. Imposing the Planck prior to the sound horizon at the baryon drag epoch, we observe support for the standard model and consistency between our constraints on the Hubble constant and the Planck value. Finally, we compare the Tsallis and $Λ$CDM cosmologies using the Akaike Information Criterion (AIC).

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N. Shahhoseini, M. Malekjani, A. Khodam-Mohammadi. 2025-01-07. $Λ$CDM Model Against Gravity-Thermodynamics Conjecture: Observational Constraints After DESI 2024. https://arxiv.org/abs/2501.03655

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