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arXiv · 2403.13708

Non-fluid like Boltzmann code architecture for early times f(T) cosmologies

Aram Aguilar·Celia Escamilla-Rivera·Jackson Levi Said·Jurgen Mifsud
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Abstract

There have been several works that have studied scalar cosmological perturbations in $f(T)$ teleparallel gravity theories to understand early cosmic times dynamics. In this direction, the perturbations presented have been performed by considering $f(T)$ extensions as an effective fluid-like scheme, where the equation-of-state contains extra terms due to the torsion. In this work, we discuss introducing a non-fluid-like approach as a direct consequence of $f(T)$ extensions, particularly for $f(T)$ power law model scenarios. This approach will be compared using CMB constraints data from Planck 2018 and SDSS catalogs, showing a change in about 17% in $C_{l}$ at $l< 10^{1}$ from the ones reported in the literature as a fluid-like approach, which will bring significant changes in the analysis on cosmological tensions at early cosmic times.

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Aram Aguilar, Celia Escamilla-Rivera, Jackson Levi Said, Jurgen Mifsud. 2024-03-20. Non-fluid like Boltzmann code architecture for early times f(T) cosmologies. https://arxiv.org/abs/2403.13708

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