Non-trivial Extension of Starobinsky Inflation

Abstract

We consider a non-canonic field in the context of Starobinsky inflation. We work in Einstein-frame. In this frame, the gravitational part of the action is equivalent to the Hilbert-Einstein action, plus a scalar field called scalaron. We investigate a model with a heavy scalaron trapped at the effective potential minimum, where its fluctuations are negligible. To be more explicit, we consider a Dirac-Born-Infeld (DBI) field, which is usually considered within the brane inflation context, as the non-canonic field. Although, the DBI field governs inflation through implicit dependence on Scalaron the boost factor, and other quantities are different from the standard DBI model. For appropriate parameters, this model is consistent with the Planck results.

23 pages, 11 figures, Revised version

References in corpus (15)

• String Cosmology: A Review
• Primordial perturbations and non-Gaussianities in DBI and general multi-field inflation
• A Microscopic Limit on Gravitational Waves from D-brane Inflation
• Curvature and isocurvature perturbations in two-field inflation
• Planck 2018 results. IX. Constraints on primordial non-Gaussianity
• K-inflationary Power Spectra in the Uniform Approximation
• Brane Inflation : String Theory viewed from the Cosmos
• Primordial black holes from modified supergravity
• Spontaneous creation of the universe from nothing
• On the equivalence between Starobinsky and Higgs inflationary models in gravity and supergravity
• Non-canonical generalizations of slow-roll inflation models
• Multi-field effects in a simple extension of $R^2$ inflation
• Brane inflation and the robustness of the Starobinsky inflationary model
• Inflation in a conformally-invariant two-scalar-field theory with an extra $R^2$ term
• Minimal Starobinsky supergravity coupled to dilaton-axion superfield