Natural Inflation with Hidden Scale Invariance

Abstract

We propose a new class of natural inflation models based on a hidden scale invariance. In a very generic Wilsonian effective field theory with an arbitrary number of scalar fields, which exhibits scale invariance via the dilaton, the potential necessarily contains a flat direction in the classical limit. This flat direction is lifted by small quantum corrections and inflation is realised without need for an unnatural fine-tuning. In the conformal limit, the effective potential becomes linear in the inflaton field, yielding to specific predictions for the spectral index and the tensor-to-scalar ratio, being respectively: $n_s-1\approx -0.025{\left(\frac{N_{\star }}{60}\right)}^{-1}$ and $r\approx 0.0667{\left(\frac{N_{\star }}{60}\right)}^{-1}$, where $N_{\star }\approx 30-65$ is a number of efolds during observable inflation. This predictions are in reasonable agreement with cosmological measurements. Further improvement of the accuracy of these measurements may turn out to be critical in falsifying our scenario.

8 pages, minor revision, to be published in PLB

References in corpus (15)

• The Standard Model Higgs boson as the inflaton
• Universality Class in Conformal Inflation
• Higgs-Dilaton Cosmology: From the Early to the Late Universe
• Dynamically Induced Planck Scale and Inflation
• Tensor to Scalar Ratio in Non-Minimal ${\varphi }^4$ Inflation
• Poincare Protection for a Natural Electroweak Scale
• Embedding inflation into the Standard Model - more evidence for classical scale invariance
• Inflation from Broken Scale Invariance
• Inflation and reheating in theories with spontaneous scale invariance symmetry breaking
• A No-Scale Inflationary Model to Fit Them All
• Classically Scale Invariant Inflation, Supermassive WIMPs, and Adimensional Gravity
• Inflation model constraints from data released in 2015
• Two-loop effective potential in quantum field theory in curved space-time
• Comments on the Hierarchy Problem in Effective Theories
• Universality Classes of Scale Invariant Inflation

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• Non-perturbative Origin of Electroweak Scale via Higgs-portal: Dyson-Schwinger in Conformally Invariant Scalar Sector
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