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arXiv · 1105.3893

Cosmic Evolution in Brans-Dicke Chameleon Cosmology

Mubasher Jamil·Ibrar Hussain·D. Momeni
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Abstract

We have investigated the Brans-Dicke Chameleon theory of gravity and obtained exact solutions of the scale factor $a(t)$, scalar field $\phi(t)$, an arbitrary function $f(\phi)$ which interact with the matter Lagrangian in the action of the Brans-Dicke Chameleon theory and potential $V(\phi)$ for different epochs of the cosmic evolution. We plot the functions $a(t)$, $\phi(t)$, $f(t)$ and $V(\phi)$ for different values of the Brans-Dicke parameter. In our models, there is no accelerating solution, only decelerating one with $q>0$. The physical cosmological distances have been investigated carefully. Further the statefinder parameters pair and deceleration parameter are discussed.

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Mubasher Jamil, Ibrar Hussain, D. Momeni. 2011-05-18. Cosmic Evolution in Brans-Dicke Chameleon Cosmology. https://doi.org/10.1140/epjp/i2011-11080-2

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