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Published on: August 12, 2013
Anisotropies in the gravitational wave background from preheating
Laura Bethke1, Daniel G Figueroa, Arttu Rajantie
1Theoretical Physics, Blackett Laboratory, Imperial College, London SW7 2AZ, United Kingdom.
Physical Review Letters
|July 19, 2013
Summary
Gravitational wave background anisotropies reveal crucial details about post-inflationary reheating dynamics. Detecting these gravitational waves could differentiate between inflationary and reheating models.
Area of Science:
- Cosmology
- Gravitational Waves
- Inflationary Theory
Background:
- Preheating after cosmic inflation generates a gravitational wave background.
- The characteristics of this background are sensitive to the underlying physics of reheating.
Purpose of the Study:
- To investigate anisotropies in the gravitational wave background produced during preheating.
- To explore the dependence of gravitational wave amplitude on model parameters.
Main Methods:
- Lattice field theory simulations of a massless preheating model.
- Analysis of gravitational wave amplitude and its angular dependence.
Main Results:
- Gravitational wave amplitude strongly depends on the light decay product field χ.
- A significant anisotropy in the gravitational wave background on large angular scales was detected.
- The specific anisotropy pattern is sensitive to reheating dynamics.
Conclusions:
- The study confirms that gravitational wave background anisotropies are a sensitive probe of reheating.
- Future gravitational wave detection experiments could observe these effects.
- This provides a potential method to distinguish between different inflationary and preheating scenarios.
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