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arXiv · 1006.2796

Chameleons with Field Dependent Couplings

Philippe Brax·Carsten van de Bruck·David F. Mota·Nelson J. Nunes·Hans A. Winther
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Abstract

Certain scalar-tensor theories exhibit the so-called chameleon mechanism, whereby observational signatures of scalar fields are hidden by a combination of self-interactions and interactions with ambient matter. Not all scalar-tensor theories exhibit such a chameleon mechanism, which has been originally found in models with inverse power run-away potentials and field independent couplings to matter. In this paper we investigate field-theories with field-dependent couplings and a power-law potential for the scalar field. We show that the theory indeed is a chameleon field theory. We find the thin-shell solution for a spherical body and investigate the consequences for Eöt-Wash experiments, fifth-force searches and Casimir force experiments. Requiring that the scalar-field evades gravitational tests, we find that the coupling is sensitive to a mass-scale which is of order of the Hubble scale today.

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Philippe Brax, Carsten van de Bruck, David F. Mota, Nelson J. Nunes, Hans A. Winther. 2010-06-14. Chameleons with Field Dependent Couplings. https://doi.org/10.1103/physrevd.82.083503

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