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arXiv · 1612.03157

No fifth force in a scale invariant universe

Pedro G. Ferreira·Christopher T. Hill·Graham G. Ross
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Abstract

We revisit the possibility that the Planck mass is spontaneously generated in scale invariant scalar-tensor theories of gravity, typically leading to a "dilaton." The fifth force, arising from the dilaton, is severely constrained by astrophysical measurements. We explore the possibility that nature is fundamentally Weyl-scale invariant and argue that, as a consequence, the fifth force effects are dramatically suppressed and such models are viable. We discuss possible obstructions to maintaining scale invariance and how these might be resolved.

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Pedro G. Ferreira, Christopher T. Hill, Graham G. Ross. 2016-12-09. No fifth force in a scale invariant universe. https://doi.org/10.1103/physrevd.95.064038

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