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Screening long-range forces through local symmetry restoration
Kurt Hinterbichler1, Justin Khoury
1Center for Particle Cosmology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Physical Review Letters
|September 28, 2010
Summary
A novel screening mechanism enables a scalar field to mediate cosmic gravitational forces while passing local gravity tests. This mechanism relies on matter-induced symmetry restoration, predicting detectable deviations from general relativity and violations of the equivalence principle.
Area of Science:
- Cosmology
- Fundamental Physics
- Gravitational Theory
Background:
- Existing theories struggle to reconcile long-range gravitational forces with stringent local gravity tests.
- Scalar fields are proposed mediators for new forces, but often conflict with experimental constraints.
Purpose of the Study:
- To introduce a screening mechanism for a long-range scalar field force.
- To ensure consistency with local tests of gravity.
- To predict observable deviations from General Relativity and the equivalence principle.
Main Methods:
- Proposing a scalar field mechanism based on local symmetry restoration in the presence of matter.
- Analyzing the field's behavior in high-density (symmetry restored) and low-density (symmetry broken) regions.
- Deriving predictions for solar system experiments and astrophysical observations.
Main Results:
- The scalar field mediates a gravitational-strength force over cosmological distances (Mpc scale).
- Symmetry restoration at high matter densities hides the force locally, satisfying gravity tests.
- Spontaneous symmetry breaking in low-density regions allows the force to manifest.
Conclusions:
- The proposed mechanism allows for a cosmologically significant scalar field force consistent with local gravity.
- Predictions include detectable deviations from General Relativity and violations of the equivalence principle.
- This model is experimentally distinguishable from Brans-Dicke gravity, chameleon theories, and brane-world gravity models.
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