Analyzing Cosmic Bubble Collisions

  title={Analyzing Cosmic Bubble Collisions},
  author={Roberto Gobbetti and Matthew Kleban},
  journal={Journal of Cosmology and Astroparticle Physics},
We develop a set of controlled, analytic approximations to study the effects of bubble collisions on cosmology. We expand the initial perturbation to the inflaton field caused by the collision in a general power series, and determine its time evolution during inflation in terms of the coefficients in the expansion. In models where the observer's bubble undergoes sufficient slow-roll inflation to solve the flatness problem, in the thin wall limit only one coefficient in the expansion is relevant… 

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