Geodesic Completeness in General Cosmological Scenarios
arXiv:2604.20809
Abstract
The well-known Borde-Guth-Vilenkin Theorem shows that inflationary spacetimes are generically geodesically past-incomplete, necessitating the existence of a pre-inflationary boundary of some sort, possibly singular. I discuss the generalization of the BGV theorem to spacetimes beyond inflation, including inhomogeneous and cyclic models. As an example, I show that the cyclic model proposed by Ijjas and Steinhardt is geodesically incomplete.
8 pages, 1 figure. To appear in the proceedings of Recontres de Moriond 2026