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arXiv · 1209.0713

Transit universe with time varying $G$ and decaying $\Lambda$

Anil Kumar Yadav·A. Sharma
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Abstract

We present the model of transit universe from early deceleration phase to current acceleration phase under the framework of general relativity in presence of gravitational coupling $G(t)$ and cosmological terms $\Lambda(t)$. The Einstein's field equations have been solved by considering time dependent deceleration parameter (DP) which renders the scale factor $a = (t^{n}e^{kt})^{\frac{1}{m}}$ where $m$, $n$ and $k$ are positive constants. The cosmological term $(\Lambda(t))$ is found to be positive and a decreasing function of time which supports the result obtained from supernovae Ia observations. The geometrical and kinematical features of the model are examined in detail.

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Anil Kumar Yadav, A. Sharma. 2012-08-19. Transit universe with time varying $G$ and decaying $\Lambda$. https://doi.org/10.1088/1674-4527/13/5/001

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