Beginning inflation in an inhomogeneous universe

@article{East2015BeginningII,
  title={Beginning inflation in an inhomogeneous universe},
  author={William E. East and Matthew Kleban and Andrei Linde and Leonardo Senatore},
  journal={Journal of Cosmology and Astroparticle Physics},
  year={2015},
  volume={2016},
  pages={010 - 010}
}
Using numerical solutions of the full Einstein field equations coupled to a scalar inflaton field in 3+1 dimensions, we study the conditions under which a universe that is initially expanding, highly inhomogeneous and dominated by gradient energy can transition to an inflationary period. If the initial scalar field variations are contained within a sufficiently flat region of the inflaton potential, and the universe is spatially flat or open on average, inflation will occur following the… 

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