Spontaneous Creation of Almost Scale - Free Density Perturbations in an Inflationary Universe

  title={Spontaneous Creation of Almost Scale - Free Density Perturbations in an Inflationary Universe},
  author={James M. Bardeen and Paul J. Steinhardt and Michael S. Turner},
  journal={Physical Review D},
The creation and evolution of energy-density perturbations are analyzed for the "new inflationary universe" scenario proposed by Linde, and Albrecht and Steinhardt. According to the scenario, the Universe underwent a strongly first-order phase transition and entered a "de Sitter phase" of exponential expansion during which all previously existing energy-density perturbations expanded to distance scales very large compared to the size of our observable Universe. The existence of an event horizon… 

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