Dynamics of the universe with variable parameters that govern the gravitational interactions
Tóm tắt
The present study investigates the Friedmann–Lemaitre–Robertson–Walker models (often FLRW models) with time varying G and
$$\Lambda $$
in the general theory of relativity. In this communication the Einstein field equations have been solved by considering the deceleration parameter q(t) as a varying function of time t and the Hubble parameter H defined as
$$q=-l(t-t_0)+\beta -1$$
and
$$q=-1+\frac{2\alpha (H-1)}{H}$$
, where
$$l,t_0,\beta , \alpha $$
are non-negative constants. We have analyzed the values of different constants that will generate a transition for the universe from an early decelerating phase to a recent acceleration phase. The physical and graphic behaviour have also been planned to study in this communication.
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