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Detecting chameleon dark energy via an electrostatic analogy
Katherine Jones-Smith1, Francesc Ferrer
1Physics Department and McDonnell Center for the Space Sciences, Washington University, St. Louis, Missouri 63130, USA.
Physical Review Letters
|September 26, 2012
Summary
Scalar fields driving cosmic acceleration exhibit a "lightning rod" effect, enhancing near pointed objects. This phenomenon, unique to scalar fields, could be detected in future experiments.
Area of Science:
- Cosmology and Astrophysics
- Theoretical Physics
- Fundamental Forces
Background:
- The accelerated expansion of the Universe suggests the influence of exotic physics beyond the standard model.
- Screened scalar field theories, such as chameleon and symmetron models, propose mechanisms for such phenomena.
- These fields are hypothesized to affect gravity on large scales while being suppressed on smaller scales.
Purpose of the Study:
- To explore the behavior of screened scalar fields around extended objects.
- To establish an analogy between scalar field theory and electrostatics for calculational purposes.
- To investigate novel experimental signatures of these scalar fields.
Main Methods:
- Developed an electrostatic analogy to model the scalar field profile around general extended bodies.
- Analyzed the field enhancement near geometric features, such as the ends of elongated objects.
- Calculated the net torque experienced by nonspherical test bodies in a background scalar field.
Main Results:
- Identified a 'lightning rod' effect where scalar fields concentrate near sharp or elongated features.
- Demonstrated that nonspherical objects experience a net torque due to this scalar field interaction.
- This torque effect has no direct analogue in standard gravitational interactions.
Conclusions:
- The electrostatic analogy provides a powerful tool for studying screened scalar fields.
- The predicted torque effect offers a unique, potentially testable signature for scalar field theories.
- Future experiments could probe these effects to constrain or confirm models of cosmic acceleration.
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