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arXiv · 1807.06467

Study of Homogeneous and Isotropic Universe in $f(R,T^φ)$ Gravity

M. Sharif·Aisha Siddiqa
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Abstract

This paper is devoted to study the cosmological behavior of homogeneous and isotropic universe model in the context of $f(R,T^φ)$ gravity where $φ$ is the scalar field. For this purpose, we follow the first order formalism defined by $H=W(φ)$. We evaluate Hubble parameter, effective equation of state parameter $(ω^{eff})$, deceleration parameter and potential of scalar field for three different values of $W(φ)$. We obtain phantom era in some cases for the early times. It is found that exponential expression of $W(φ)$ yields $ω^{eff}$ independent of time for flat universe and independent of model parameter otherwise. It is concluded that our model corresponds to $Λ$CDM for both initial as well as late times.

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M. Sharif, Aisha Siddiqa. 2018-07-16. Study of Homogeneous and Isotropic Universe in $f(R,T^φ)$ Gravity. https://arxiv.org/abs/1807.06467

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