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arXiv · 2302.07132

Cosmological models in $f (T, \mathcal{T})$ gravity and the dynamical system analysis

L. K. Duchaniya·Santosh V Lohakare·B. Mishra
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Abstract

The study addresses matter-coupled modified gravity, particularly $f (T, \mathcal{T})$ gravity, unveiling distinct formalism. The research further discusses stability analysis, and the dynamical system approach, exploring the dynamics of critical points to understand these models' viability better. The dynamical system analysis of the cosmological models in $f(T, \mathcal{T})$ gravity, where $T$ and $\mathcal{T}$ respectively represent the torsion scalar and trace of the energy-momentum tensor has been investigated. It demonstrates how first-order autonomous systems can be treated as cosmological equations and analyzed using standard dynamical system theory techniques. Two forms of the function $f(T,\mathcal{T})$ are considered (i) one with the product of trace and higher order torsion scalar and the other (ii) linear combination of linear trace and squared torsion. By employing this methodology, the research aims to uncover the actual behavior of the Universe. The findings emphasize the graphical representation of these insights, enriching our understanding of cosmological scenarios.

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L. K. Duchaniya, Santosh V Lohakare, B. Mishra. 2023-02-13. Cosmological models in $f (T, \mathcal{T})$ gravity and the dynamical system analysis. https://doi.org/10.1016/j.dark.2023.101402

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