Rollercoaster cosmology

  title={Rollercoaster cosmology},
  author={Guido D’Amico and Nemanja Kaloper},
  journal={Journal of Cosmology and Astroparticle Physics},
Does inflation have to happen all in one go? The answer is a resounding no! All cosmological problems can be solved by a sequence of short bursts of cosmic acceleration, interrupted by short epochs of decelerated expansion. The spectrum of perturbations will still match the CMB and LSS if the earliest stage of the last O(50)- O(60) efolds is at least O(15) efolds long. Other stages can be considerably shorter. But as long as they add up to O(50)- O(60) efolds and the stages of decelerated… Expand
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  • L. Anguelova
  • Physics
  • Journal of Cosmology and Astroparticle Physics
  • 2021
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