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Structure formation constraints on the Jordan-Brans-Dicke theory

Viviana Acquaviva·Carlo Baccigalupi·Samuel M. Leach·Andrew R. Liddle·Francesca Perrotta
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Abstract

We use cosmic microwave background data from WMAP, ACBAR, VSA and CBI, and galaxy power spectrum data from 2dF, to constrain flat cosmologies based on the Jordan-Brans-Dicke theory, using a Markov Chain Monte Carlo approach. Using a parametrization based on ξ=1/4ω, and performing an exploration in the range \lnξ\in [-9,3], we obtain a 95% marginalized probability bound of \lnξ< -6.2, corresponding to a 95% marginalized probability lower bound on the Brans-Dicke parameter ω>120.

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Viviana Acquaviva, Carlo Baccigalupi, Samuel M. Leach, Andrew R. Liddle, Francesca Perrotta. 2005-05-09. Structure formation constraints on the Jordan-Brans-Dicke theory. https://doi.org/10.1103/physrevd.71.104025

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