On testing and extending the inflationary consistency relation for tensor modes

Abstract

If observations confirm BICEP2's claim of a tensor-scalar ratio $r\approx 0.2$ on CMB scales, then the inflationary consistency relation $n_t=-r/8$ predicts a small negative value for the tensor spectral index $n_t$. We show that future CMB polarization experiments should be able to confirm this prediction at several sigma. We also show how to properly extend the consistency relation to solar system scales, where the primordial gravitational wave density ${\Omega }_{gw}$ could be measured by proposed experiments such as the Big Bang Observer. This would provide a far more stringent test of the consistency relation and access much more detailed information about the early universe.

6 pages, 4 figures, matches Phys.Rev.D version

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Cited by in corpus (10)

• The Quest for B Modes from Inflationary Gravitational Waves
• String Gas Cosmology after Planck
• Running from Features: Optimized Evaluation of Inflationary Power Spectra
• Non-Gaussian Structure of B-mode Polarization after Delensing
• Breaking of Spatial Diffeomorphism Invariance, Inflation and the Spectrum of Cosmological Perturbations
• Differentiating G-inflation from String Gas Cosmology using the Effective Field Theory Approach
• Future detectability of gravitational-wave induced lensing from high-sensitivity CMB experiments
• Improving Constraints on Inflation with CMB Delensing
• Observational Status of Tachyon Natural Inflation and Reheating
• Pseudo-Periodic Natural Higgs Inflation