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Testing for w<-1 in the Solar System

Jerome Martin·Carlo Schimd·Jean-Philippe Uzan
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Abstract

In scalar-tensor theories of gravity, the equation of state of dark energy, w, can become smaller than -1 without violating any energy condition. The value of w today is tied to the level of deviations from general relativity which, in turn, is constrained by solar system and pulsars timing experiments. The conditions on these local constraints for w to be significantly less than -1 are established. It is demonstrated that this requires to consider theories that differ from the Jordan-Fierz-Brans-Dicke theory and that involve either a steep coupling function or a steep potential. It is also shown how a robust measurement of w could probe scalar-tensor theories.

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Jerome Martin, Carlo Schimd, Jean-Philippe Uzan. 2005-10-07. Testing for w<-1 in the Solar System. https://doi.org/10.1103/physrevlett.96.061303

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