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arXiv · 2204.07604

Curvature dominance DE-model in $f(R)$-gravity

G. K. Goswami·Rita Rani·Harshna Balhara·J. K. Singh
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Abstract

We have probed a cosmological model in $f(R)$-gravity, which is a cubic equation in scalar curvature $R$. The terms arise due to nonlinear $f(R)$ function are treated as energy due to curvature inspired geometry. As a result, we find accelerating expansion in the universe, which creates an anti-gravitating negative pressure in it. Some of the physical parameters are solved using numerical methods. The evolution of the model are examined by the latest observational Hubble data (46-data points) and Pantheon data (the latest compilation of SNIa with 40 binned in the redshift range $0.014 \leqslant z \leqslant1.62$). Some important features of the model have been discussed by analyzing the plots of various dynamical parameters. The plots of deceleration parameter $q$ and the Hubble parameter $H$ describe the accelerating expansion in the evolution of the Universe at the present epoch. The transition from deceleration to acceleration for our model is obtained at redshift $z_{tr} \simeq 0.694069$, which is in good agreement with $\Lambda$CDM. We have also carried out state finder analysis for our model. The analysis of specific features of the model confirms that our model is consistent with $\Lambda$CDM in late times.

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G. K. Goswami, Rita Rani, Harshna Balhara, J. K. Singh. 2022-04-15. Curvature dominance DE-model in $f(R)$-gravity. https://doi.org/10.1007/s12648-023-02674-3

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