Modulated preheating and isocurvature perturbations
| Autor: | Stanislav Rusak, Kari Enqvist |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
Physics
Coupling Inflation (cosmology) Cosmology and Nongalactic Astrophysics (astro-ph.CO) Cold dark matter Field (physics) 010308 nuclear & particles physics Gravitational wave FOS: Physical sciences Spectral density Astronomy and Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics Astrophysics Inflaton 01 natural sciences 7. Clean energy 3. Good health General Relativity and Quantum Cosmology 13. Climate action Quantum electrodynamics 0103 physical sciences 010306 general physics Scalar field Astrophysics - Cosmology and Nongalactic Astrophysics |
| Zdroj: | Journal of Cosmology and Astroparticle Physics. 2013:017-017 |
| ISSN: | 1475-7516 |
| Popis: | We consider a model of preheating where the coupling of the inflaton to the preheat field is modulated by an additional scalar field which is light during inflation. We establish that such a model produces the observed curvature perturbation analogously to the modulated reheating scenario. The contribution of modulated preheating to the power spectrum and to non-Gaussianity can however be significantly larger compared to modulated perturbative reheating. We also consider the implications of the current constraints on isocurvature perturbations in case where the modulating field is responsible for cold dark matter. We find that existing bounds on CDM isocurvature perturbations imply that modulated preheating is unlikely to give a dominant contribution to the curvature perturbation and that the same bounds suggest important constraints on non-Gaussianity and the amount of primordial gravitational waves. 17 pages, 12 figures. Added comments on loop effects. Matches JCAP published version |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|