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arXiv · 2009.03252

Cosmological models with squared trace in modified gravity

B. Mishra·S. K. Tripathy·Saibal Ray
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Abstract

In this work we present a few simple cosmological models under the modified theory of gravity in the particular form of $f(R,\mathcal{T})=R+2f(\mathcal{T})$, where $R$ is the Ricci Scalar and $\mathcal{T}$ is the trace of the energy-momentum tensor. Two special cosmological models are studied with (i) hyperbolic scale factor and (ii) specific form of the Hubble parameter. The models are observed to predict relevant cosmological parameters closer to the observational values. Both the models reduce to overlap with the $\Lambda$CDM model at late times. We have discussed some interesting results related to wormhole solutions as evolved from our model. The possible occurrence of Big Trip in wormholes for the models are also discussed.

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B. Mishra, S. K. Tripathy, Saibal Ray. 2020-09-02. Cosmological models with squared trace in modified gravity. https://doi.org/10.1142/s021827182050100x

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