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arXiv · 2403.07130

Selecting energy-momentum trace dependent gravity theories with LSS

Jonas Pinheiro da Silva·Hermano Velten
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Abstract

We study scalar cosmological perturbations in $f(R, T)$ modified gravity theories being $T$ the trace of the energy-momentum tensor. We provide detailed equations for the matter energy density contrast. We solve then numerically to promote a comparison with available large scale structure (LSS) formation observational data on $f \sigma_8$ and also addressing the $S_8$ tension. We identify $f(R,T)$ models that lead either to growth enhancement or suppression. Since recent results in the literature indicate a preference for the latter feature, this type of analysis is quite useful to select viable modifications of gravity. We studied class of such $f(R,T)$ models are either ruled out or severely restricted.

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Jonas Pinheiro da Silva, Hermano Velten. 2024-03-11. Selecting energy-momentum trace dependent gravity theories with LSS. https://arxiv.org/abs/2403.07130

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