2010/07/14 by William H. Kinney, William H Kinney, Azadeh Moradinezhad Dizgah · 1 citation
Mathematics · Physics and Astronomy · #Adiabatic process #Black Holes and Theoretical Physics #Classical mechanics #Cosmology #Cosmology and Gravitation Theories #Dual (grammatical number) #Duality (order theory) #Flow (mathematics) #Galaxies: Formation, Evolution, Phenomena #Inflation (cosmology) #Invariant (physics) #Limit (mathematics) #Mathematical analysis #Mathematical physics #Mathematics #Mechanics #Physics #Pure mathematics #Quantum mechanics #Spectral density #Superposition principle #Theoretical physics #astro-ph.CO #gr-qc #hep-th
paper · pdf · doi:10.1103/physrevd.82.083506
published as Phys.Rev.D82:083506,2010 · 14 pages, LaTeX (V2: reference added, version submitted to PRD)
arxiv created 2010/07/14 · openalex publication_date 2010/10/07 · arxiv updated 2014/11/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
In this paper, we use a known duality between expanding and contracting cosmologies to construct a dual of the inflationary flow hierarchy applicable to contracting cosmologies such as ekpyrotic and cyclic models. We show that the inflationary flow equations are invariant under the duality and therefore apply equally well to inflation or to cyclic cosmology. We construct a self-consistent small-parameter approximation dual to the slow-roll approximation in inflation, and calculate the power spectrum of perturbations in this limit. We also recover the matter-dominated contracting solution of Wands, and the recently proposed adiabatic ekpyrosis solution.