Simulating the universe(s): from cosmic bubble collisions to cosmological observables with numerical relativity

  title={Simulating the universe(s): from cosmic bubble collisions to cosmological observables with numerical relativity},
  author={Carroll L. Wainwright and Matthew Camp Johnson and Hiranya V. Peiris and Anthony Aguirre and Luis Lehner and Steven L. Liebling},
  journal={Journal of Cosmology and Astroparticle Physics},
The theory of eternal inflation in an inflaton potential with multiple vacua predicts that our universe is one of many bubble universes nucleating and growing inside an ever-expanding false vacuum. The collision of our bubble with another could provide an important observational signature to test this scenario. We develop and implement an algorithm for accurately computing the cosmological observables arising from bubble collisions directly from the Lagrangian of a single scalar field. We first… 
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