Shortcomings of new parametrizations of inflation

2016/09/30 by Jerome Martin, Jérôme Martin, Christophe Ringeval +1 · 5 citations
Earth and Planetary Sciences · Mathematics · Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmic microwave background #Cosmology and Gravitation Theories #Geometry #Geophysics and Gravity Measurements #Inflation (cosmology) #Mathematics #Observable #Physics #Quantum mechanics #Scalar (mathematics) #Spectral index #Spectral line #Tensor (intrinsic definition) #Theoretical physics #astro-ph.CO #gr-qc #hep-ph #hep-th

paper · pdf · doi:10.1103/physrevd.94.123521

published as Phys. Rev. D 94, 123521 (2016) · 13 pages, 2 figures, uses RevTeX. References added, matches published version

openalex publication_date 2016/12/22 · arxiv created 2017/01/13 · arxiv updated 2017/01/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

In the hope of avoiding model dependence of the cosmological observables, phenomenological parametrizations of cosmic inflation have recently been proposed. Typically, they are expressed in terms of two parameters associated with an expansion of the inflationary quantities matching the belief that inflation is characterized by two numbers only, the tensor-to-scalar ratio and the scalar spectral index. We give different arguments and examples showing that these new approaches are either not generic or insufficient to make predictions at the accuracy level needed by the cosmological data. We conclude that disconnecting inflation from high energy physics and gravity might not be the most promising way to learn about the physics of the early Universe.

Citations

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Cited by

• Time-reversed Stochastic Inflation
• Reconstruction of extended inflationary potentials for attractors
• The stochastic spectator
• Probing the BSM physics with CMB precision cosmology: an application to supersymmetry
• Reconstruction of constant slow-roll inflation