Post-inflation increase of the cosmological tensor-to-scalar perturbation ratio

Abstract

We investigate the possibility that the amplitude of scalar density perturbations may be damped after inflation. This would imply that CMB anisotropies do not uniquely fix the amplitude of the perturbations generated during inflation and that the present tensor-to-scalar ratio might be larger than produced in inflation, increasing the prospects of detection of primordial gravitational radiation. It turns out, however, that the damping of density perturbations is hard to achieve.

arXiv comment4-page latex file with NO figures. We would like to thank M. Sloth for very useful correspondence about his related paper and for readily pointing out an error in the first version of our draft. We thank A. Linde, D. Lyth, S. Mukhanov L. McAllister, M. Sasaki and D. Wands for useful comments and criticisms

References in corpus (15)

• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Preliminary Maps and Basic Results
• de Sitter Vacua in String Theory
• Particle Physics Models of Inflation and the Cosmological Density Perturbation
• 4-Year COBE DMR Cosmic Microwave Background Observations: Maps and Basic Results
• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Implications for Inflation
• Signature of Gravity Waves in Polarization of the Microwave Background
• A Probe of Primordial Gravity Waves and Vorticity
• What would we learn by detecting a gravitational wave signal in the cosmic microwave background anisotropy?
• Model Independent Properties and Cosmological Implications of the Dilaton and Moduli Sectors of 4-d Strings
• A limit on the detectability of the energy scale of inflation
• Scales and hierarchies in warped compactifications and brane worlds
• Power Spectrum of Primordial Inhomogeneity Determined from the 4-Year COBE DMR Sky Maps
• Separation of Gravitational-Wave and Cosmic-Shear Contributions to Cosmic Microwave Background Polarization
• The Cosmology of String Theoretic Axions
• WMAPping inflationary physics

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• Inconsistency of an inflationary sector coupled only to Einstein gravity
• Effects of quantum gravity on the inflationary parameters and thermodynamics of the early universe
• Non-Gaussianity, Isocurvature Perturbation, Gravitational Waves and a No-Go Theorem for Isocurvaton
• Temporal enhancement of super-horizon curvature perturbations from decays of two curvatons and its cosmological consequences
• Modulation of the waterfall by a gauge field
• Gravity of Cosmological Perturbations in the CMB
• Inflationary Hubble Parameter from the Gravitational Wave Spectrum in the General Slow-roll Approximation