2015/07/31 by Sander Mooij, Gonzalo A. Palma, Grigoris Panotopoulos +1 · 27 citations
Earth and Planetary Sciences · Mathematics · Physics and Astronomy · #Bispectrum #Black Holes and Theoretical Physics #Consistency (knowledge bases) #Cosmology and Gravitation Theories #Curvature #Geometry #Geophysics and Gravity Measurements #Inflation (cosmology) #Mathematics #Physics #Quantum mechanics #Scalar (mathematics) #Spectral density #Spectral line #Statistical physics #Statistics #Theoretical physics #astro-ph.CO #gr-qc #hep-ph #hep-th
paper · pdf · doi:10.1088/1475-7516/2015/10/062
published in Journal of Cosmology and Astroparticle Physics 2015(10), 062 (Institute of Physics) · 39 pages, 5 figures. v2: no changes in the contents, version submitted to JCAP. v3: minor changes, added section 2.5, updated references, accepted by JCAP. v4: corrected equations 2.25 and A.34
openalex publication_date 2015/10/28 · arxiv created 2016/01/28 · arxiv updated 2016/01/29 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study the generation of sharp features in the primordial spectra within the framework of effective field theory of inflation, wherein curvature perturbations are the consequence of the dynamics of a single scalar degree of freedom. We identify two sources in the generation of features: rapid variations of the sound speed c s (at which curvature fluctuations propagate) and rapid variations of the expansion rate H during inflation. With this in mind, we propose a non-trivial relation linking these two quantities that allows us to study the generation of sharp features in realistic scenarios where features are the result of the simultaneous occurrence of these two sources. This relation depends on a single parameter with a value determined by the particular model (and its numerical input) responsible for the rapidly varying background. As a consequence, we find a one-parameter consistency relation between the shape and size of features in the bispectrum and features in the power spectrum. To substantiate this result, we discuss several examples of models for which this one-parameter relation (between c s and H ) holds, including models in which features in the spectra are both sudden and resonant .