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arXiv · 2010.02753

Constraints on Energy Momentum Squared Gravity from cosmic chronometers and Supernovae Type Ia data

Chayan Ranjit·Prabir Rudra·Sujata Kundu
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Abstract

In this work we perform an observational data analysis on the energy momentum squared gravity model. Possible solutions for matter density are obtained from the model and their cosmological implications are studied. Some recent observational data is used to constrain model parameters using statistical techniques. We have used the cosmic chronometer and SNe Type-Ia Riess (292) $H(z)-z$ data-sets in our study. Along with the data-sets we have also used baryon acoustic oscillation (BAO) peak parameter and cosmic microwave background (CMB) peak parameter to obtain bounds on the model parameters. Joint analysis of the data with the above mentioned parameters have been performed to obtain better results. For the statistical analysis we have used the minimization technique of the $χ^{2}$ statistic. Using this tool we have constrained the free parameters of the model. Confidence contours have been generated for the predicted values of the free parameters at the $66\%$, $90\%$ and $99\%$ confidence levels. Finally we have compared our analysis with the union2 data sample presented by Amanullah et al.,2010 and the recently published Pantheon data sample. Finally a multi-component model is investigated by adding dust to a general cosmological fluid with equation of state $w=-1/3$. The density parameters were studied and their values were found to comply with the observational results.

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Chayan Ranjit, Prabir Rudra, Sujata Kundu. 2021-03-24. Constraints on Energy Momentum Squared Gravity from cosmic chronometers and Supernovae Type Ia data. https://doi.org/10.1016/j.aop.2021.168432

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