Anisotropic Cosmological Evolution in f(R,T) Gravity: Exact Solutions for Bianchi Type-V Universe

Year 2025, Volume: 11 Issue: 3, 297 - 308, 30.09.2025

Aylin Çalışkan

https://doi.org/10.28979/jarnas.1746551

Abstract

In this study, we investigate the Bianchi type-V cosmological model filled with a perfect fluid characterized by a constant equation of state parameter within the framework of f(R,T) gravity. By adopting the physically justified assumption that the shear scalar is proportional to the expansion scalar, we derive exact analytical solutions to the modified gravitational field equations in f(R,T) gravity. We also derive the models key physical and geometrical parameters, and analyze their dynamical evolution in terms of cosmic time t. We then provide graphical representations to illustrate the temporal behavior of relevant cosmological quantities. The results indicate the model exhibits a phase of accelerated expansion, which is consistent with recent observational data. However, the universe does not evolve toward isotropy; instead, it originates from a Big Bang-type initial singularity.

Keywords

Bianchi type-V universe , modified gravity , exact solution , anisotropic universe

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