Understanding large scale CMB anomalies with the generalized non-minimal derivative coupling during inflation

Abstract

We study the observational implications of a class of inflationary models wherein the inflaton is coupled to the Einstein tensor through a generalized non-minimal derivative coupling (GNMDC). In particular, we explore whether these models can generate suitable features in the primordial spectrum of curvature perturbations as a possible explanation for the large-scale anomalies associated with the angular power spectrum of CMB temperature anisotropies. We derive model-independent constraints on the GNMDC function for such a scenario, considering both the scalar and tensor perturbations. We modify CosmoMC to accommodate our GNMDC framework and investigate different classes of inflationary models using a fully consistent numerical approach. We find that the hilltop-quartic model with a specific choice of the GNMDC function provides a considerable improvement over the best-fit reference $\Lambda$CDM model with a nearly scale-invariant power spectrum. While the large-scale structure observations should be able to provide independent constraints, future CMB experiments, such as CMB-S4 and CMB-Bharat, are expected to constrain further the parameter space of such beyond canonical single-field inflationary models.

v1: 34 pages, 7 figures, 4 tables; v2: 26 pages, 8 figures, 4 tables, published in Phys. Rev. D

References in corpus (28)

• Gravitational Waves and Gamma-rays from a Binary Neutron Star Merger: GW170817 and GRB 170817A
• Covariant Galileon
• BICEP / Keck XIII: Improved Constraints on Primordial Gravitational Waves using Planck, WMAP, and BICEP/Keck Observations through the 2018 Observing Season
• Generalized Galileons: All scalar models whose curved background extensions maintain second-order field equations and stress tensors
• Horndeski theory and beyond: a review
• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Angular Power Spectra
• Generation and Characterization of Large Non-Gaussianities in Single Field Inflation
• Black holes with non-minimal derivative coupling
• Inflation and WMAP three year data: Features have a Future!
• LiteBIRD: JAXA's new strategic L-class mission for all-sky surveys of cosmic microwave background polarization
• New Constraints on Oscillations in the Primordial Spectrum of Inflationary Perturbations
• Whipped inflation
• Combining power spectrum and bispectrum measurements to detect oscillatory features
• Precise measurements of inflationary features with 21 cm observations
• Spectrum oscillations from features in the potential of single-field inflation
• Primordial black holes in nonminimal derivative coupling inflation with quartic potential and reheating consideration
• On the evolution of tachyonic perturbations at super-Hubble scales
• Uncovering the History of Cosmic Inflation from Anomalies in Cosmic Microwave Background Spectra
• Primordial black holes ensued from exponential potential and coupling parameter in nonminimal derivative inflation model
• Primordial Standard Clock Models and CMB Residual Anomalies
• The large scale CMB cut-off and the tensor-to-scalar ratio
• Comparing multi-field primordial feature models with the Planck data
• Observing nulling of primordial correlations via the 21 cm signal
• Successful Higgs inflation from combined nonminimal and derivative couplings
• New constraints on primordial features from the galaxy two-point correlation function
• Effect of transitions in the Planck mass during inflation on primordial power spectra
• Nonlinear reconstruction of features in the primordial power spectrum from large-scale structure
• Detectable Data-driven Features in the Primordial Scalar Power Spectrum

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• Choice of vacuum state and the relation between inflationary and Planck scales
• Particle production during Inflation with a non-minimally coupled spectator scalar field
• Intermediate inflation in generalized non-minimal derivative coupling model