Inflation without a beginning: A Null boundary proposal

  title={Inflation without a beginning: A Null boundary proposal},
  author={Anthony Aguirre and Steven Gratton},
  journal={Physical Review D},
We develop our recent suggestion that inflation may be made past eternal, so that there is no initial cosmological singularity or "beginning of time". Inflation with multiple vacua generically approaches a steady-state statistical distribution of regions at these vacua, and our model follows directly from making this distribution hold at all times. We find that this corresponds (at the semi-classical level) to particularly simple cosmological boundary conditions on an infinite null surface near… 

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