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Stability, dark energy parameterization and swampland aspect of Bianchi Type-$ VI_{h}$ cosmological models with f(R, T)-gravity

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 نشر من قبل Dr. Anirudh Pradhan
 تاريخ النشر 2020
  مجال البحث فيزياء
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Stability, dark energy (DE) parameterization and swampland aspects for the Bianchi form-$VI_{h}$ universe have been formulated in an extended gravity hypothesis. Here we have assumed a minimally coupled geometry field with a rescaled function of $f(R, T)$ replaced in the geometric action by the Ricci scalar $R$. Exact solutions are sought under certain basic conditions for the related field equations. For the following theoretically valid premises, the field equations in this scalar-tensor theory have been solved. It is observed under appropriate conditions that our model shows a decelerating to accelerating phase transition property. Results are observed to be coherent with recent observations. Here, our models predict that the universes rate of expansion will increase with the passage of time. The physical and geometric aspects of the models are discussed in detail. In this model, we also analyze the parameterizations of dark energy by fitting the EoS parameter $omega(z)$ with redshift. The results obtained would be useful in clarifying the relationship between dark energy parameters. In this, we also explore the correspondence of swampland dark energy. The swampland criteria have also been shown the nature of the scalar field and the potential of the scalar field.

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