Running Spectral Index as a Probe of Physics at High Scales

Abstract

The WMAP results on the scalar spectral index n and its running with scale, though preliminary, open a very interesting window to physics at very high energies. We address the problem of finding inflaton potentials well motivated by particle physics which can accomodate WMAP data. We make a model independent analysis of a large class of models: those with flat tree-level potential lifted by radiative corrections, which cause the slow rolling of the inflaton and the running of n. This includes typical hybrid inflation models. In the small-coupling regime the predictions for the size and running of n are remarkably neat, e.g. -dn/dln k=(n-1)^2 << 1, and n does not cross n=1, contrary to WMAP indications. On the other hand, n can run significantly if the couplings are stronger but at the price of having a small number of e-folds, Ne. We also examine the effect of mass thresholds crossed during inflation. Finally, we show that the presence of non-renormalizable operators for the inflaton, suppressed by a mass scale above the inflationary range, is able to give both dn/dln k ~ O(-0.05) and Ne ~ 50.

arXiv comment33 pages, LaTeX, 5 ps figures. Minor errata fixed, refs. added. Matches published version

References in corpus (29)

• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Determination of Cosmological Parameters
• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Preliminary Maps and Basic Results
• Particle Physics Models of Inflation and the Cosmological Density Perturbation
• Hybrid Inflation
• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Implications for Inflation
• Natural Inflation: Particle Physics Models, Power Law Spectra for Large Scale Structure, and Constraints from COBE
• D-Term Inflation
• Reconstructing the primordial power spectrum
• Flat directions in the scalar potential of the supersymmetric standard model
• Two-loop effective potential for a general renormalizable theory and softly broken supersymmetry
• Multiple inflation
• Non-commutative inflation and the CMB
• Loop quantum gravity effects on inflation and the CMB
• CMB Power Spectrum from Noncommutative Spacetime
• Effective Field Theories and Inflation
• Inflation with a running spectral index in supergravity
• Noncommutative Inflation and the CMB Multipoles
• Power Spectra in Spacetime Noncommutative Inflation
• Running of the Scalar Spectral Index from Inflationary Models
• Running of the Spectral Index and Violation of the Consistency Relation Between Tensor and Scalar Spectra from trans-Planckian Physics
• What Can WMAP Tell Us About The Very Early Universe? New Physics as an Explanation of Suppressed Large Scale Power and Running Spectral Index
• Chaotic hybrid new inflation in supergravity with a running spectral index
• Inflation in string-inspired cosmology and suppression of CMB low multipoles
• An inflation model with large variations in spectral index
• On the accuracy of slow-roll inflation given current observational constraints
• Running of the Scalar Spectral Index and Observational Signatures of Inflation
• Reconstructing large running-index inflaton potentials
• F-term inflation in Superstring Theories
• Radiative Corrections to the Inflaton Potential as an Explanation of Suppressed Large Scale Power in Density Perturbations and the Cosmic Microwave Background

Cited by in corpus (35)

• Particle physics models of inflation and curvaton scenarios
• Improved measurements of the temperature and polarization of the CMB from QUaD
• Supergravity based inflation models: a review
• Black hole formation and slow-roll inflation
• Implications of a Running Spectral Index for Slow Roll Inflation
• Power Spectrum of the Density Perturbations From Smooth Hybrid New Inflation Model
• Reconstructing a general inflationary action
• Suppressing the impact of a high tensor-to-scalar ratio on the temperature anisotropies
• Single-field inflation constraints from CMB and SDSS data
• Constraining Inflation
• Cosmological constraints on general, single field inflation
• Radiative plateau inflation
• Kaehler Potentials for Hilltop F-term Hybrid Inflation
• Single field inflation with modulated potential in light of the Planck and BICEP2
• Cyclic Inflation
• Joint Planck and WMAP Assessment of Low CMB Multipoles
• A Bayesian analysis of inflationary primordial spectrum models using Planck data
• How to constrain inflationary parameter space with minimal priors
• Reducing the spectral index in F-term hybrid inflation through a complementary modular inflation
• When can the Planck satellite measure spectral index running?
• Large tensor-to-scalar ratio and running of the scalar spectral index with Instep Inflation
• A Note on Noncommutative Brane Inflation
• Flat Tree-level Inflationary Potentials in Light of CMB and LSS Data
• Weighing neutrinos in the presence of a running primordial spectral index
• Noncommutative KKLMMT Model
• Closed inflationary universe with tachyonic field
• Radiative Corrections from Heavy Fast-Roll Fields during Inflation
• Braneworld inflation from an effective field theory after WMAP three-year data
• A falsely fat curvaton with an observable running of the spectral tilt
• F-Term Hybrid Inflation Followed by a Peccei-Quinn Phase Transition
• Slow-roll reconstruction for running spectral index
• Inflation and nonequilibrium renormalization group
• CMB and LSS constraints on a single-field model of inflation
• Reducing the Tension Between the BICEP2 and the Planck Measurements: A Complete Exploration of the Parameter Space
• Constraining the primordial power spectrum using a differentiable likelihood