2008/06/30 by Lotfi Boubekeur, Paolo Creminelli, Jorge Noreña +2 · 62 citations
Physics and Astronomy · #Action (physics) #Barotropic fluid #Black Holes and Theoretical Physics #Cosmological model #Cosmological perturbation theory #Cosmology and Gravitation Theories #Equivalence (formal languages) #Lagrangian #Metric (unit) #Nonlinear system #Perturbation (astronomy) #Pulsars and Gravitational Waves Research #Scalar field #astro-ph #gr-qc #hep-th
paper · pdf · doi:10.1088/1475-7516/2008/08/028
published in Journal of Cosmology and Astroparticle Physics 2008(08), 028 (Institute of Physics) · 16 pages. New version, typo fixed in eq. (91)
arxiv created 2008/08/04 · openalex publication_date 2008/08/26 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
We study nonlinear cosmological perturbations during post-inflationary evolution, using the equivalence between a perfect barotropic fluid and a derivatively coupled scalar field with Lagrangian . Since this Lagrangian is just a special case of k -inflation, this approach is analogous to the one employed in the study of non-Gaussianities from inflation. We use this method to derive the second-order metric during matter dominance in the comoving gauge directly as a function of the primordial inflationary perturbation ζ. Going to Poisson gauge, we recover the metric previously derived in the literature.