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Reconstruction of a scalar-tensor theory of gravity in an accelerating universe

B. Boisseau·G. Esposito-Farese·D. Polarski·A. A. Starobinsky
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Abstract

The present acceleration of the Universe strongly indicated by recent observational data can be modeled in the scope of a scalar-tensor theory of gravity. We show that it is possible to determine the structure of this theory (the scalar field potential and the functional form of the scalar-gravity coupling) along with the present density of dustlike matter from the following two observable cosmological functions: the luminosity distance and the linear density perturbation in the dustlike matter component as functions of redshift. Explicit results are presented in the first order in the small inverse Brans-Dicke parameter 1/omega.

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B. Boisseau, G. Esposito-Farese, D. Polarski, A. A. Starobinsky. 2000-01-21. Reconstruction of a scalar-tensor theory of gravity in an accelerating universe. https://doi.org/10.1103/physrevlett.85.2236

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