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arXiv · 1105.4929

Cosmological Perturbation Analysis in a Scale Invariant Model of Gravity

Pankaj Jain·Purnendu Karmakar·Subhadip Mitra·Sukanta Panda·Naveen K. Singh
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Abstract

We consider a model for gravity that is invariant under global scale transformations. It includes one extra real scalar field coupled non-minimally to the gravity fields. In this model all the dimensionful parameters like the gravitational constant and the cosmological constant etc. are generated by a solution of the classical equations of motion which breaks scale invariance. In this paper we demonstrate the stability of such a solution against small perturbations in a flat FRW background by making a perturbative expansion around this solution and solving the resulting equations linear in the perturbations.

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Pankaj Jain, Purnendu Karmakar, Subhadip Mitra, Sukanta Panda, Naveen K. Singh. 2012-02-03. Cosmological Perturbation Analysis in a Scale Invariant Model of Gravity. https://doi.org/10.1088/0264-9381%2F28%2F21%2F215010

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