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arXiv · 1607.02356

Post-Newtonian parameter $\gamma$ for multiscalar-tensor gravity with a general potential

Manuel Hohmann·Laur Jarv·Piret Kuusk·Erik Randla·Ott Vilson
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Abstract

We compute the parametrized post-Newtonian parameter $\gamma$ in the case of a static point source for multiscalar-tensor gravity with completely general nonderivative couplings and potential in the Jordan frame. Similarly to the single massive field case $\gamma$ depends exponentially on the distance from the source and is determined by the length of a vector of non-minimal coupling in the space of scalar fields and its orientation relative to the mass eigenvectors. Using data from the Cassini tracking experiment, we estimate bounds on a general theory with two scalar fields. Our formalism can be utilized for a wide range of models, which we illustrate by applying it to nonminimally coupled Higgs SU(2) doublet, general hybrid metric-Palatini gravity, linear ($\Box^{-1}$) and quadratic ($\Box^{-2}$) nonlocal gravity.

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Manuel Hohmann, Laur Jarv, Piret Kuusk, Erik Randla, Ott Vilson. 2016-07-08. Post-Newtonian parameter $\gamma$ for multiscalar-tensor gravity with a general potential. https://doi.org/10.1103/physrevd.94.124015

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