Gopi Kant Goswami | Searcharxiv

arXiv2019

A Dark Energy Quintessence Model of the Universe

In this paper, we have presented a model of the FLRW universe filled with matter and dark energy fluids, by assuming an ansatz that deceleration parameter is a linear function of the Hubble constant. This results in a time-dependent DP having decelerating-accelerating transition phase of the universe. This is a quintessence model $ω_{(de)}\geq -1$. The quintessence phase remains for the period $(0 \leq z \leq 0.5806)$. The model is shown to satisfy current observational constraints. Various cosmological parameters relating to the history of the universe have been investigated.

gr-qc↗

arXiv2017

Bianchi type-I Dust Filled Accelerating Brans- Dicke Cosmology

In this paper, spatially homogeneous and anisotropic Bianchi type-I cosmological models of Brans-Dicke theory of gravitation are investigated. The model represents accelerating universe at present and is considered to be dominated by dark energy. Cosmological constant $Λ$ is considered as a candidate for the dark energy that has negative pressure and is responsible for the present acceleration. The derived model agrees at par with the recent SN Ia observations. We have set BD-coupling constant $ω$ to be ~$40000$, ~seeing the solar system tests and evidences. We have discussed the various physical and geometrical properties of the models and have compared them with the corresponding relativistic models.

physics.gen-ph↗