Reconciling tensor and scalar observables in G-inflation

@article{Ramirez2018ReconcilingTA,
title={Reconciling tensor and scalar observables in G-inflation},
author={H'ector Ram'irez and Samuel Passaglia and Hayato Motohashi and Wayne Hu and Olga Mena},
journal={arXiv: Cosmology and Nongalactic Astrophysics},
year={2018}
}
The simple $m^2\phi^2$ potential as an inflationary model is coming under increasing tension with limits on the tensor-to-scalar ratio $r$ and measurements of the scalar spectral index $n_s$. Cubic Galileon interactions in the context of the Horndeski action can potentially reconcile the observables. However, we show that this cannot be achieved with only a constant Galileon mass scale because the interactions turn off too slowly, leading also to gradient instabilities after inflation ends…
8 Citations

Figures from this paper

Warm G inflation: Intermediate model
• Physics
Physical Review D
• 2019
A warm-intermediate inflationary universe model is studied in the presence of the Galileon coupling $G(\phi,X)=g(\phi)X$. General conditions required for successful inflation are deduced and
Inflation with derivative self-interaction and coupling to gravity
We consider a subclass of Horndeski theories for studying cosmic inflation. In particular, we investigate models of inflation in which the derivative self-interaction of the scalar field and the
Chaotic inflation and reheating in generalized scalar-tensor gravity
• Physics
Journal of Cosmology and Astroparticle Physics
• 2021
In the present work, we study slow-roll inflation in scalar-tensor gravity theories in the presence of both the non-minimal coupling between the scalar field and curvature, and the Galileon
Noncanonical Approaches To Inflation
In this Thesis by publication, we cover both phenomenological and theoretical approaches to the study of inflation: from model-independent parametrizations to modifications of gravity. In a review
Resonant reconciliation of convex-potential inflation models and the Planck data
• Physics
Physical Review D
• 2019
We consider single field chaotic inflationary models plus a cosine modulation term, as in axion monodromy models, and augment it by a light scalar field with similar cosine coupling. We show the
Scalar bispectrum beyond slow-roll in the unified EFT of inflation
• Physics
Physical Review D
• 2018
We present a complete formulation of the scalar bispectrum in the unified effective field theory (EFT) of inflation, which includes the Horndeski and beyond-Horndeski GLPV classes, in terms of a set
Effective field theory of degenerate higher-order inflation
• Physics
• 2020
We extend the effective field theory of inflation to a general Lagrangian constructed from Arnowitt-Deser-Misner variables that encompasses the most general interactions with up to second derivatives
The Black Hole Window on Cosmic Inflation
We develop in this thesis the principles governing the production of our universe's primordial inhomogeneities during its early phase of inflation. As a guiding thread we ask what physics during

References

SHOWING 1-10 OF 86 REFERENCES
Potential-driven Galileon inflation
• Physics
• 2012
For the models of inflation driven by the potential energy of an inflaton field $\phi$, the covariant Galileon Lagrangian $(\partial\phi)^2\Box \phi$ generally works to slow down the evolution of the
On inflation with non-minimal coupling
A simple realization of inflation consists of adding the following operators to the Einstein-Hilbert action: (∂ϕ)2, λϕ4, and ξϕ2R, with ξ a large non-minimal coupling. Recently there has been much
Running from features: Optimized evaluation of inflationary power spectra
• Physics
• 2015
In models like axion monodromy, temporal features during inflation which are not associated with its ending can produce scalar, and to a lesser extent, tensor power spectra where deviations from
Generalized Slow Roll in the Unified Effective Field Theory of Inflation
• Physics
• 2017
We provide a compact and unified treatment of power spectrum observables for the effective field theory (EFT) of inflation with the complete set of operators that lead to second-order equations of
Planck 2015. XX. Constraints on inflation
We analyse the implications of the Planck data for cosmic inflation. The Planck nominal mission temperature anisotropy measurements, combined with the WMAP large-angle polarization, constrain the
Monodromy in the CMB: Gravity Waves and String Inflation
• Physics
• 2008
We present a simple mechanism for obtaining large-field inflation, and hence a gravitational wave signature, from string theory compactified on twisted tori. For nil manifolds, we obtain a leading
Tensor to Scalar Ratio in Non-Minimal $\phi^4$ Inflation
• Physics
• 2010
We reconsider non-minimal \lambda \phi^4 chaotic inflation which includes the gravitational coupling term \xi \mathcal{R} \phi^2, where \phi denotes a gauge singlet inflaton field and \mathcal{R} is
Inflation driven by the Galileon field.
• Physics, Medicine
Physical review letters
• 2010
It is shown that (almost) scale-invariant curvature fluctuations can be generated even in the exactly de Sitter background and that the tensor-to-scalar ratio can take a significantly larger value than in the standard inflation models, violating the standard consistency relation.
α-attractors: Planck, LHC and dark energy
• Physics
• 2015
A bstractWe develop four-parameter supergravity models of inflation and dark energy, constrained so that δρρ$$\frac{\delta \rho }{\rho }$$, ns and the cosmological constant Λ take their known
Generalized slow roll for tensor fluctuations
The recent BICEP2 detection of degree scale CMB B-mode polarization, coupled with a deficit of observed power in large angle temperature anisotropy, suggest that the slow-roll parameter $\epsilon_H$,