Past-completeness of inflationary spacetimes

  title={Past-completeness of inflationary spacetimes},
  author={Joseph Lesnefsky and Damien A Easson and Paul C. W. Davies},
  journal={Physical Review D},
We discuss the question of whether or not inflationary spacetimes can be geodesically complete in the infinite past. Geodesic completeness is a necessary condition for averting an initial singularity during eternal inflation. It is frequently argued that cosmological models which are expanding sufficiently fast (having average Hubble expansion rate $H_{avg}>0$) must be incomplete in null and timelike past directions. This well-known conjecture relies on specific bounds on the integral of the… 
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