Non-Gaussianity, spectral index, and tensor modes in mixed inflaton and curvaton models

2008/02/29 by Kazuhide Ichikawa, Teruaki Suyama, Tomo Takahashi +1 · 5 citations
Mathematics · Physics and Astronomy · #Cosmic background radiation #Cosmic microwave background #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #Inflation (cosmology) #Inflaton #Mathematics #Non-Gaussianity #Physics #Quantum mechanics #Scalar (mathematics) #Solar and Space Plasma Dynamics #Spectral density #Spectral index #Spectral line #Statistical physics #Statistics #Tensor (intrinsic definition) #Theoretical physics #astro-ph #hep-ph

paper · pdf · doi:10.1103/physrevd.78.023513

published as Phys.Rev.D78:023513,2008 · 40 pages, 16 figures, discussions added, references added

openalex publication_date 2008/07/11 · arxiv created 2008/08/04 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

We study non-Gaussianity, the spectral index of primordial scalar fluctuations, and tensor modes in models where fluctuations from the inflaton and the curvaton can both contribute to the present cosmic density fluctuations. Even though simple single-field inflation models generate only tiny non-Gaussianity, if we consider such a mixed scenario, large non-Gaussianity can be produced. Furthermore, we study the inflationary parameters such as the spectral index and the tensor-to-scalar ratio in this kind of models and discuss in what cases models predict the spectral index and tensor modes allowed by the current data while generating large non-Gaussianity, which may have many implications for model-buildings of the inflationary universe.

Citations

• Probing String Theory with Modulated Cosmological Fluctuations
• Primordial curvature fluctuation and its non-Gaussianity in models with modulated reheating
• Generating the curvature perturbation without an inflaton
• WMAP normalization of inflationary cosmologies
• Cosmic string from D-term inflation and curvaton
• Inflation models and observation
• Mixed inflaton and curvaton perturbations
• Evolution of second-order cosmological perturbations and non-Gaussianity
• Primordial trispectrum from inflation
• A General Analytic Formula for the Spectral Index of the Density Perturbations produced during Inflation
• Primordial density perturbation in the curvaton scenario
• Super-Horizon Scale Dynamics of Multi-Scalar Inflation
• Cosmological constraints from the SDSS luminous red galaxies
• Cosmological perturbations from varying masses and couplings
• Three‐YearWilkinson Microwave Anisotropy Probe(WMAP) Observations: Implications for Cosmology
• Natural Chaotic Inflation in Supergravity
• Non-Gaussianity from tachyonic preheating in hybrid inflation
• Chaotic inflation

Cited by

• Inflation with an extra light scalar field after Planck
• Non-Gaussianities of single field inflation with nonminimal coupling
• The void abundance with non-gaussian primordial perturbations
• ϕ4inflation is not excluded
• Non-Gaussianity and baryonic isocurvature fluctuations in the curvaton scenario