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Illusions of general relativity in Brans-Dicke gravity

Valerio Faraoni
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Abstract

Contrary to common belief, the standard tenet of Brans-Dicke theory reducing to general relativity when omega tends to infinity is false if the trace of the matter energy-momentum tensor vanishes. The issue is clarified in a new approach using conformal transformations. The otherwise unaccountable limiting behavior of Brans-Dicke gravity is easily understood in terms of the conformal invariance of the theory when the sources of gravity have radiation-like properties. The rigorous computation of the asymptotic behavior of the Brans-Dicke scalar field is straightforward in this new approach.

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Valerio Faraoni. 1999-02-26. Illusions of general relativity in Brans-Dicke gravity. https://doi.org/10.1103/physrevd.59.084021

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