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تسجيل مستخدم جديدTransit cosmological models coupled with zero-mass scalar-field with high redshift in higher derivative theory
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The present study deals with a flat FRW cosmological model filled with perfect fluid coupled with the zero-mass scalar field in the higher derivative theory of gravity. We have obtained two types of universe models, the first one is the accelerating universe (power-law cosmology) and the second one is the transit phase model (hyperbolic expansion-law). We have obtained various physical and kinematic parameters and discussed them with observationally constrained values of $H_{0}$. The transit redshift value is obtained $z_{t}=0.414$ where the transit model shows signature-flipping and is consistent with recent observations. In our models, the present values of EoS parameter $omega_{0}$ crosses the cosmological constant value $omega_{0}=-1$. Also, the present age of the universe is calculated.
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