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arXiv · 1007.2792

Equivalence Principle Violations and Couplings of a Light Dilaton

Thibault Damour·John F. Donoghue
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Abstract

We consider possible violations of the equivalence principle through the exchange of a light `dilaton-like' scalar field. Using recent work on the quark-mass dependence of nuclear binding, we find that the dilaton-quark-mass coupling induces significant equivalence-principle-violating effects varying like the inverse cubic root of the atomic number - A^{-1/3}. We provide a general parameterization of the scalar couplings, but argue that two parameters are likely to dominate the equivalence-principle phenomenology. We indicate the implications of this framework for comparing the sensitivities of current and planned experimental tests of the equivalence principle.

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Thibault Damour, John F. Donoghue. 2010-07-19. Equivalence Principle Violations and Couplings of a Light Dilaton. https://doi.org/10.1103/physrevd.82.084033

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