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arXiv · 1012.0846

Towards a Cosmological Dual to Inflation

Justin Khoury·Godfrey E. J. Miller
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Abstract

We derive all single-field cosmologies with unit sound speed that generate scale invariant curvature perturbations on a dynamical attractor background. We identify three distinct phases: slow-roll inflation; a slowly contracting adiabatic ekpyrotic phase, described by a rapidly-varying equation of state; and a novel adiabatic ekpyrotic phase on a slowly expanding background. All of these yield identical power spectra. The degeneracy is broken at the 3-point level: unlike the nearly gaussian spectrum of slow-roll inflation, adiabatic ekpyrosis predicts large non-gaussianities on small scales.

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Justin Khoury, Godfrey E. J. Miller. 2011-06-30. Towards a Cosmological Dual to Inflation. https://doi.org/10.1103/physrevd.84.023511

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