2014/03/31 by Xin Gao, Tianjun Li, Pramod Shukla · 2 citations
Physics and Astronomy · #Anisotropy #Black Holes and Theoretical Physics #Cosmic microwave background #Cosmology #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #Inflation (cosmology) #Inflaton #Mathematical physics #Observable #Physics #Planck #Quantum mechanics #Scalar field #Slow roll #Theoretical physics #astro-ph.CO #gr-qc #hep-th
paper · pdf · doi:10.1088/1475-7516/2014/10/008
published as JCAP 1410 (2014) 008 · version 2, 32 pages, 1 table and 12 figures, major revision as per referee's suggestions, to appear in JCAP
arxiv created 2014/09/30 · openalex publication_date 2014/10/06 · arxiv updated 2014/10/07 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
Using δ N formalism, in the context of a generic multi-field inflation driven on a non-flat field space background, we revisit the analytic expressions of the various cosmological observables such as scalar/tensor power spectra, scalar/tensor spectral tilts, non-Gaussianity parameters, tensor-to-scalar ratio, and the various runnings of these observables. In our backward formalism approach, the subsequent expressions of observables automatically include the terms beyond the leading order slow-roll expansion correcting many of the expression at subleading order. To connect our analysis properly with the earlier results, we rederive the (well) known (single field) expressions in the limiting cases of our generic formulae. Further, in the light of PLANCK results, we examine for the compatibility of the consistency relations within the slow-roll regime of a two-field roulette poly-instanton inflation realized in the context of large volume scenarios.