# On the past-completeness of inflationary spacetimes

@inproceedings{Lesnefsky2022OnTP, title={On the past-completeness of inflationary spacetimes}, author={Joseph Lesnefsky and Damien A Easson and Paul C. W. Davies}, year={2022} }

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 Hubble…

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