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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 16, 2013
Runaway dilaton and equivalence principle violations
Thibault Damour1, Federico Piazza, Gabriele Veneziano
1Institut des Hautes Etudes Scientifiques, 35 route de Chartres, F-91440 Bures-sur-Yvette, France.
Physical Review Letters
|August 23, 2002
Summary
A new cosmological scenario suggests that a runaway dilaton could be detected through improved tests of free-fall universality. Such a dilaton might also cause detectable variations in fundamental constants, impacting dark matter and dark energy research.
Area of Science:
- Cosmology
- String Theory
- Fundamental Physics
Background:
- A proposed cosmological scenario involves a dilaton field decoupling while approaching infinite bare string coupling.
- Residual interactions of this dilaton are linked to primordial density fluctuations from inflation.
Purpose of the Study:
- To investigate the detectability of residual dilaton interactions.
- To explore the potential for a runaway dilaton to induce variations in fundamental constants.
Main Methods:
- Relating dilaton interactions to the amplitude of inflationary density fluctuations.
- Analyzing the impact of dilaton couplings to dark matter and dark energy.
Main Results:
- Dilaton interactions are potentially detectable with modest improvements in free-fall universality tests.
- A runaway dilaton with significant couplings could induce observable time variations in natural constants.
Conclusions:
- The proposed dilaton scenario offers testable predictions for near-future experiments.
- Observational constraints on free-fall universality and variations in fundamental constants can probe this cosmological model.
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